Bumped version to 0.10.2

Schedule SCTP recv task only if necessary

.github/FUNDING.yml

@@ -1 +1,3 @@
+github: ['paullouisageneau']
 custom: ['https://paypal.me/paullouisageneau']
+

.github/workflows/build-gnutls.yml

@@ -12,11 +12,11 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: install packages
-      run: sudo apt update && sudo apt install libgnutls28-dev nettle-dev
+      run: sudo apt update && sudo apt install libgnutls28-dev nettle-dev libsrtp2-dev
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_GNUTLS=1
+      run: cmake -B build -DUSE_GNUTLS=1 -DUSE_SYSTEM_SRTP=1 -DWARNINGS_AS_ERRORS=1
     - name: make
       run: (cd build; make -j2)
     - name: test
@@ -30,7 +30,7 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_GNUTLS=1
+      run: cmake -B build -DUSE_GNUTLS=1 -DWARNINGS_AS_ERRORS=1 -DENABLE_LOCAL_ADDRESS_TRANSLATION=1
     - name: make
       run: (cd build; make -j2)
     - name: test

.github/workflows/build-nice.yml

@@ -7,7 +7,7 @@ on:
     branches:
     - master
 jobs:
-  build-linux:
+  build-media:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
@@ -16,7 +16,21 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_GNUTLS=1 -DUSE_NICE=1
+      run: cmake -B build -DUSE_GNUTLS=1 -DUSE_NICE=1 -DWARNINGS_AS_ERRORS=1
+    - name: make
+      run: (cd build; make -j2)
+    - name: test
+      run: ./build/tests
+  build-no-media:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: install packages
+      run: sudo apt update && sudo apt install libgnutls28-dev libnice-dev
+    - name: submodules
+      run: git submodule update --init --recursive
+    - name: cmake
+      run: cmake -B build -DUSE_GNUTLS=1 -DUSE_NICE=1 -DNO_MEDIA=1 -DWARNINGS_AS_ERRORS=1
     - name: make
       run: (cd build; make -j2)
     - name: test

.github/workflows/build-openssl.yml

@@ -12,11 +12,11 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: install packages
-      run: sudo apt update && sudo apt install libssl-dev
+      run: sudo apt update && sudo apt install libssl-dev libsrtp2-dev
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_GNUTLS=0
+      run: cmake -B build -DUSE_GNUTLS=0 -DUSE_SYSTEM_SRTP=1 -DWARNINGS_AS_ERRORS=1
     - name: make
       run: (cd build; make -j2)
     - name: test
@@ -26,11 +26,11 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: install packages
-      run: brew reinstall openssl@1.1
+      run: HOMEBREW_NO_INSTALL_CLEANUP=1 brew reinstall openssl@1.1
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_GNUTLS=0
+      run: cmake -B build -DUSE_GNUTLS=0 -WARNINGS_AS_ERRORS=1 -DENABLE_LOCAL_ADDRESS_TRANSLATION=1
       env:
         OPENSSL_ROOT_DIR: /usr/local/opt/openssl
         OPENSSL_LIBRARIES: /usr/local/opt/openssl/lib
@@ -48,10 +48,11 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -G "NMake Makefiles" -DUSE_GNUTLS=0
+      run: cmake -B build -G "NMake Makefiles" -DUSE_GNUTLS=0 -WARNINGS_AS_ERRORS=1
     - name: nmake
       run: |
         cd build
+        set CL=/MP
         nmake
     - name: test
       run: build/tests.exe

.gitmodules

@@ -10,3 +10,6 @@
 [submodule "deps/json"]
 	path = deps/json
 	url = https://github.com/nlohmann/json.git
+[submodule "deps/libsrtp"]
+	path = deps/libsrtp
+	url = https://github.com/cisco/libsrtp.git

CMakeLists.txt

@@ -1,15 +1,20 @@
 cmake_minimum_required(VERSION 3.7)
 project(libdatachannel
-	DESCRIPTION "WebRTC Data Channels Library"
-	VERSION 0.7.2
+	VERSION 0.10.2
 	LANGUAGES CXX)
+set(PROJECT_DESCRIPTION "WebRTC Data Channels Library")
 
 # Options
 option(USE_GNUTLS "Use GnuTLS instead of OpenSSL" OFF)
 option(USE_NICE "Use libnice instead of libjuice" OFF)
-option(USE_SRTP "Enable SRTP for media support" OFF)
+option(USE_SYSTEM_SRTP "Use system libSRTP" OFF)
 option(NO_WEBSOCKET "Disable WebSocket support" OFF)
+option(NO_MEDIA "Disable media transport support" OFF)
 option(NO_EXAMPLES "Disable examples" OFF)
+option(NO_TESTS "Disable tests build" OFF)
+option(WARNINGS_AS_ERRORS "Treat warnings as errors" OFF)
+option(RSA_KEY_BITS_2048 "Use 2048-bit RSA key instead of 3072-bit" OFF)
+option(CAPI_STDCALL "Set calling convention of C API callbacks stdcall" OFF)
 
 if(USE_NICE)
 	option(USE_JUICE "Use libjuice" OFF)
@@ -18,9 +23,12 @@ else()
 endif()
 
 if(USE_GNUTLS)
-	option(USE_NETTLE "Use Nettle instead of OpenSSL in libjuice" ON)
+	option(USE_NETTLE "Use Nettle in libjuice" ON)
 else()
-	option(USE_NETTLE "Use Nettle instead of OpenSSL in libjuice" OFF)
+	option(USE_NETTLE "Use Nettle in libjuice" OFF)
+	if(NOT USE_SYSTEM_SRTP)
+		option(ENABLE_OPENSSL "Enable OpenSSL crypto engine for SRTP" ON)
+	endif()
 endif()
 
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
@@ -47,12 +55,15 @@ set(LIBDATACHANNEL_SOURCES
 	${CMAKE_CURRENT_SOURCE_DIR}/src/icetransport.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/init.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/log.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/message.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/peerconnection.cpp
-	${CMAKE_CURRENT_SOURCE_DIR}/src/rtc.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/rtcp.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/sctptransport.cpp
-	${CMAKE_CURRENT_SOURCE_DIR}/src/tls.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/threadpool.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/tls.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/track.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/processor.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/capi.cpp
 )
 
 set(LIBDATACHANNEL_WEBSOCKET_SOURCES
@@ -71,6 +82,7 @@ set(LIBDATACHANNEL_HEADERS
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/configuration.hpp
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/datachannel.hpp
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/description.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/rtcp.hpp
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/include.hpp
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/init.hpp
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/log.hpp
@@ -80,13 +92,17 @@ set(LIBDATACHANNEL_HEADERS
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/reliability.hpp
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/rtc.h
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/rtc.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/rtp.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/track.hpp
 	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/websocket.hpp
 )
 
 set(TESTS_SOURCES
     ${CMAKE_CURRENT_SOURCE_DIR}/test/main.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/test/connectivity.cpp
-    ${CMAKE_CURRENT_SOURCE_DIR}/test/capi.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/track.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/capi_connectivity.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/capi_track.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/test/websocket.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/test/benchmark.cpp
 )
@@ -99,17 +115,15 @@ set(CMAKE_POLICY_DEFAULT_CMP0048 NEW)
 add_subdirectory(deps/plog)
 
 option(sctp_build_programs 0)
+option(sctp_build_shared_lib 0)
 add_subdirectory(deps/usrsctp EXCLUDE_FROM_ALL)
 if (MSYS OR MINGW)
 	target_compile_definitions(usrsctp PUBLIC -DSCTP_STDINT_INCLUDE=<stdint.h>)
-	target_compile_definitions(usrsctp-static PUBLIC -DSCTP_STDINT_INCLUDE=<stdint.h>)
 endif()
 if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
     target_compile_options(usrsctp PRIVATE -Wno-error=format-truncation)
-	target_compile_options(usrsctp-static PRIVATE -Wno-error=format-truncation)
 endif()
 add_library(Usrsctp::Usrsctp ALIAS usrsctp)
-add_library(Usrsctp::UsrsctpStatic ALIAS usrsctp-static)
 
 if (NO_WEBSOCKET)
 	add_library(datachannel SHARED
@@ -140,20 +154,26 @@ target_include_directories(datachannel PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/includ
 target_include_directories(datachannel PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include/rtc)
 target_include_directories(datachannel PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
 target_link_libraries(datachannel PUBLIC Threads::Threads plog::plog)
-target_link_libraries(datachannel PRIVATE Usrsctp::UsrsctpStatic)
+target_link_libraries(datachannel PRIVATE Usrsctp::Usrsctp)
 
 target_include_directories(datachannel-static PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
 target_include_directories(datachannel-static PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include/rtc)
 target_include_directories(datachannel-static PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
 target_link_libraries(datachannel-static PUBLIC Threads::Threads plog::plog)
-target_link_libraries(datachannel-static PRIVATE Usrsctp::UsrsctpStatic)
+target_link_libraries(datachannel-static PRIVATE Usrsctp::Usrsctp)
 
 if(WIN32)
-	target_link_libraries(datachannel PRIVATE wsock32 ws2_32) # winsock2
-	target_link_libraries(datachannel-static PRIVATE wsock32 ws2_32) # winsock2
+	target_link_libraries(datachannel PRIVATE ws2_32) # winsock2
+	target_link_libraries(datachannel-static PRIVATE ws2_32) # winsock2
 endif()
 
-if(USE_SRTP)
+if(NO_MEDIA)
+	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_MEDIA=0)
+	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_MEDIA=0)
+else()
+	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_MEDIA=1)
+	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_MEDIA=1)
+	if(USE_SYSTEM_SRTP)
 		find_package(SRTP REQUIRED)
 		if(NOT TARGET SRTP::SRTP)
 			add_library(SRTP::SRTP UNKNOWN IMPORTED)
@@ -162,13 +182,17 @@ if(USE_SRTP)
 				IMPORTED_LINK_INTERFACE_LANGUAGES C
 				IMPORTED_LOCATION ${SRTP_LIBRARIES})
 		endif()
-	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_MEDIA=1)
-	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_MEDIA=1)
+		target_compile_definitions(datachannel PRIVATE RTC_SYSTEM_SRTP=1)
+		target_compile_definitions(datachannel-static PRIVATE RTC_SYSTEM_SRTP=1)
 		target_link_libraries(datachannel PRIVATE SRTP::SRTP)
 		target_link_libraries(datachannel-static PRIVATE SRTP::SRTP)
-else()
-	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_MEDIA=0)
-	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_MEDIA=0)
+	else()
+		add_subdirectory(deps/libsrtp EXCLUDE_FROM_ALL)
+		target_compile_definitions(datachannel PRIVATE RTC_SYSTEM_SRTP=0)
+		target_compile_definitions(datachannel-static PRIVATE RTC_SYSTEM_SRTP=0)
+		target_link_libraries(datachannel PRIVATE srtp2)
+		target_link_libraries(datachannel-static PRIVATE srtp2)
+	endif()
 endif()
 
 if (USE_GNUTLS)
@@ -207,44 +231,77 @@ else()
 	target_link_libraries(datachannel-static PRIVATE LibJuice::LibJuiceStatic)
 endif()
 
+if(RSA_KEY_BITS_2048)
+	target_compile_definitions(datachannel PUBLIC RSA_KEY_BITS_2048)
+	target_compile_definitions(datachannel-static PUBLIC RSA_KEY_BITS_2048)
+endif()
+
+if(CAPI_STDCALL)
+	target_compile_definitions(datachannel PUBLIC CAPI_STDCALL)
+	target_compile_definitions(datachannel-static PUBLIC CAPI_STDCALL)
+endif()
+
 add_library(LibDataChannel::LibDataChannel ALIAS datachannel)
 add_library(LibDataChannel::LibDataChannelStatic ALIAS datachannel-static)
 
 install(TARGETS datachannel LIBRARY DESTINATION lib)
 install(FILES ${LIBDATACHANNEL_HEADERS} DESTINATION include/rtc)
 
-# Tests
-add_executable(datachannel-tests ${TESTS_SOURCES})
-set_target_properties(datachannel-tests PROPERTIES
-	VERSION ${PROJECT_VERSION}
-	CXX_STANDARD 17)
-set_target_properties(datachannel-tests PROPERTIES OUTPUT_NAME tests)
-target_include_directories(datachannel-tests PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
-if(WIN32)
-	target_link_libraries(datachannel-tests datachannel-static) # DLL exports only the C API
-else()
-	target_link_libraries(datachannel-tests datachannel)
+if(NOT MSVC)
+	target_compile_options(datachannel PRIVATE -Wall -Wextra)
+	target_compile_options(datachannel-static PRIVATE -Wall -Wextra)
 endif()
 
-# Benchmark
-add_executable(datachannel-benchmark test/benchmark.cpp)
-set_target_properties(datachannel-benchmark PROPERTIES
+if(WARNINGS_AS_ERRORS)
+	if(MSVC)
+		target_compile_options(datachannel PRIVATE /WX)
+		target_compile_options(datachannel-static PRIVATE /WX)
+	else()
+		target_compile_options(datachannel PRIVATE -Werror)
+		target_compile_options(datachannel-static PRIVATE -Werror)
+	endif()
+endif()
+
+# Tests
+if(NOT NO_TESTS)
+	add_executable(datachannel-tests ${TESTS_SOURCES})
+	set_target_properties(datachannel-tests PROPERTIES
 		VERSION ${PROJECT_VERSION}
 		CXX_STANDARD 17)
-set_target_properties(datachannel-benchmark PROPERTIES OUTPUT_NAME benchmark)
-target_compile_definitions(datachannel-benchmark PRIVATE BENCHMARK_MAIN=1)
-target_include_directories(datachannel-benchmark PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
-if(WIN32)
+	if(NOT CMAKE_SYSTEM_NAME STREQUAL "WindowsStore") # Prevent a bug in manifest generation for UWP
+		set_target_properties(datachannel-tests PROPERTIES OUTPUT_NAME tests)
+	endif()
+	target_include_directories(datachannel-tests PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
+	if(WIN32)
+		target_link_libraries(datachannel-tests datachannel-static) # DLL exports only the C API
+	else()
+		target_link_libraries(datachannel-tests datachannel)
+	endif()
+
+	# Benchmark
+	add_executable(datachannel-benchmark test/benchmark.cpp)
+	set_target_properties(datachannel-benchmark PROPERTIES
+		VERSION ${PROJECT_VERSION}
+		CXX_STANDARD 17)
+	if(NOT CMAKE_SYSTEM_NAME STREQUAL "WindowsStore") # Prevent a bug in manifest generation for UWP
+		set_target_properties(datachannel-benchmark PROPERTIES OUTPUT_NAME benchmark)
+	endif()
+	target_compile_definitions(datachannel-benchmark PRIVATE BENCHMARK_MAIN=1)
+	target_include_directories(datachannel-benchmark PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
+	if(WIN32)
 		target_link_libraries(datachannel-benchmark datachannel-static) # DLL exports only the C API
-else()
+	else()
 		target_link_libraries(datachannel-benchmark datachannel)
+	endif()
 endif()
 
 # Examples
-if(NOT NO_EXAMPLES)
+if(NOT NO_EXAMPLES AND NOT CMAKE_SYSTEM_NAME STREQUAL "WindowsStore")
 	set(JSON_BuildTests OFF CACHE INTERNAL "")
 	add_subdirectory(deps/json)
 	add_subdirectory(examples/client)
+	add_subdirectory(examples/media)
+	add_subdirectory(examples/sfu-media)
 	add_subdirectory(examples/copy-paste)
 	add_subdirectory(examples/copy-paste-capi)
 endif()

README.md

@@ -1,6 +1,6 @@
 # libdatachannel - C/C++ WebRTC Data Channels
 
-libdatachannel is a standalone implementation of WebRTC Data Channels and WebSockets in C++17 with C bindings for POSIX platforms (including Linux and Apple macOS) and Microsoft Windows. It enables direct connectivity between native applications and web browsers without the pain of importing the entire WebRTC stack. The interface consists of simplified versions of the JavaScript WebRTC and WebSocket APIs present in browsers, in order to ease the design of cross-environment applications.
+libdatachannel is a standalone implementation of WebRTC Data Channels, WebRTC Media Transport, and WebSockets in C++17 with C bindings for POSIX platforms (including GNU/Linux, Android, and Apple macOS) and Microsoft Windows. It enables direct connectivity between native applications and web browsers without the pain of importing the entire WebRTC stack. The interface consists of simplified versions of the JavaScript WebRTC and WebSocket APIs present in browsers, in order to ease the design of cross-environment applications.
 It can be compiled with multiple backends:
 - The security layer can be provided through [OpenSSL](https://www.openssl.org/) or [GnuTLS](https://www.gnutls.org/).
 - The connectivity for WebRTC can be provided through my ad-hoc ICE library [libjuice](https://github.com/paullouisageneau/libjuice) as submodule or through [libnice](https://github.com/libnice/libnice).
@@ -13,12 +13,13 @@ Licensed under LGPLv2, see [LICENSE](https://github.com/paullouisageneau/libdata
 
 The library aims at implementing the following communication protocols:
 
-### WebRTC Data Channel
+### WebRTC Data Channels and Media Transport
 
 The WebRTC stack has been tested to be compatible with Firefox and Chromium.
 
 Protocol stack:
 - SCTP-based Data Channels ([draft-ietf-rtcweb-data-channel-13](https://tools.ietf.org/html/draft-ietf-rtcweb-data-channel-13))
+- SRTP-based Media Transport ([draft-ietf-rtcweb-rtp-usage-26](https://tools.ietf.org/html/draft-ietf-rtcweb-rtp-usage-26))
 - DTLS/UDP ([RFC7350](https://tools.ietf.org/html/rfc7350) and [RFC8261](https://tools.ietf.org/html/rfc8261))
 - ICE ([RFC8445](https://tools.ietf.org/html/rfc8445)) with STUN ([RFC5389](https://tools.ietf.org/html/rfc5389))
 
@@ -26,9 +27,11 @@ Features:
 - Full IPv6 support
 - Trickle ICE ([draft-ietf-ice-trickle-21](https://tools.ietf.org/html/draft-ietf-ice-trickle-21))
 - JSEP compatible ([draft-ietf-rtcweb-jsep-26](https://tools.ietf.org/html/draft-ietf-rtcweb-jsep-26))
+- SRTP and SRTCP key derivation from DTLS ([RFC5764](https://tools.ietf.org/html/rfc5764))
 - Multicast DNS candidates ([draft-ietf-rtcweb-mdns-ice-candidates-04](https://tools.ietf.org/html/draft-ietf-rtcweb-mdns-ice-candidates-04))
 - TURN relaying ([RFC5766](https://tools.ietf.org/html/rfc5766)) with [libnice](https://github.com/libnice/libnice) as ICE backend
-- SRTP media transport ([RFC3711](https://tools.ietf.org/html/rfc3711)) with [libSRTP](https://github.com/cisco/libsrtp)
+
+Note only SDP BUNDLE mode is supported for media multiplexing ([draft-ietf-mmusic-sdp-bundle-negotiation-54](https://tools.ietf.org/html/draft-ietf-mmusic-sdp-bundle-negotiation-54)). The behavior is equivalent to the JSEP bundle-only policy: the library always negociates one unique network component, where SRTP media streams are multiplexed with SRTCP control packets ([RFC5761](https://tools.ietf.org/html/rfc5761)) and SCTP/DTLS data traffic ([RFC5764](https://tools.ietf.org/html/rfc5764)).
 
 ### WebSocket
 
@@ -50,10 +53,11 @@ Dependencies:
 Submodules:
 - libjuice: https://github.com/paullouisageneau/libjuice
 - usrsctp: https://github.com/sctplab/usrsctp
+- libsrtp: https://github.com/cisco/libsrtp
 
 Optional dependencies:
-- libnice: https://nice.freedesktop.org/ (only if selected as ICE backend instead of libjuice)
-- libSRTP: https://github.com/cisco/libsrtp (only necessary for supporting media transport)
+- libnice: https://nice.freedesktop.org/ (if selected as ICE backend instead of libjuice)
+- libsrtp: https://github.com/cisco/libsrtp (if selected instead of the submodule)
 
 ## Building
 
@@ -78,6 +82,29 @@ $ cd build
 $ make -j2
 ```
 
+#### Apple macOS with XCode project
+
+```bash
+$ cmake -B "$BUILD_DIR" -DUSE_GNUTLS=0 -DUSE_NICE=0 -G Xcode
+```
+
+Xcode project is generated in *build/* directory.
+
+##### Solving **Could NOT find OpenSSL** error
+
+You need to add OpenSSL root directory if your build fails with the following message:
+
+```
+Could NOT find OpenSSL, try to set the path to OpenSSL root folder in the
+system variable OPENSSL_ROOT_DIR (missing: OPENSSL_CRYPTO_LIBRARY
+OPENSSL_INCLUDE_DIR)
+```
+
+for example:
+```bash
+$ cmake -B build -DUSE_GNUTLS=0 -DUSE_NICE=0 -G Xcode -DOPENSSL_ROOT_DIR=/usr/local/Cellar/openssl\@1.1/1.1.1h/
+```
+
 #### Microsoft Windows with MinGW cross-compilation
 ```bash
 $ cmake -B build -DCMAKE_TOOLCHAIN_FILE=/usr/share/mingw/toolchain-x86_64-w64-mingw32.cmake # replace with your toolchain file
@@ -104,7 +131,7 @@ $ make USE_GNUTLS=1 USE_NICE=0
 
 See [examples](https://github.com/paullouisageneau/libdatachannel/blob/master/examples/) for a complete usage example with signaling server (under GPLv2).
 
-Additionnaly, you might want to have a look at the [C API](https://github.com/paullouisageneau/libdatachannel/blob/dev/include/rtc/rtc.h).
+Additionnaly, you might want to have a look at the [C API](https://github.com/paullouisageneau/libdatachannel/blob/master/include/rtc/rtc.h).
 
 ### Signal a PeerConnection
 
@@ -118,12 +145,12 @@ config.iceServers.emplace_back("mystunserver.org:3478");
 
 auto pc = make_shared<rtc::PeerConnection>(config);
 
-pc->onLocalDescription([](const rtc::Description &sdp) {
+pc->onLocalDescription([](rtc::Description sdp) {
     // Send the SDP to the remote peer
     MY_SEND_DESCRIPTION_TO_REMOTE(string(sdp));
 });
 
-pc->onLocalCandidate([](const rtc::Candidate &candidate) {
+pc->onLocalCandidate([](rtc::Candidate candidate) {
     // Send the candidate to the remote peer
     MY_SEND_CANDIDATE_TO_REMOTE(candidate.candidate(), candidate.mid());
 });
@@ -159,7 +186,7 @@ dc->onOpen([]() {
     cout << "Open" << endl;
 });
 
-dc->onMessage([](const variant<binary, string> &message) {
+dc->onMessage([](variant<binary, string> message) {
     if (holds_alternative<string>(message)) {
         cout << "Received: " << get<string>(message) << endl;
     }
@@ -186,7 +213,7 @@ ws->onOpen([]() {
 	cout << "WebSocket open" << endl;
 });
 
-ws->onMessage([](const variant<binary, string> &message) {
+ws->onMessage([](variant<binary, string> message) {
     if (holds_alternative<string>(message)) {
         cout << "WebSocket received: " << get<string>(message) << endl;
     }
@@ -197,6 +224,8 @@ ws->open("wss://my.websocket/service");
 ```
 
 ## External resources
-- Rust wrappers for libdatachannel: [datachannel-rs](https://github.com/lerouxrgd/datachannel-rs)
-- WebAssembly wrappers compatible with libdatachannel: [datachannel-wasm](https://github.com/paullouisageneau/datachannel-wasm)
+- Rust wrapper for libdatachannel: [datachannel-rs](https://github.com/lerouxrgd/datachannel-rs)
+- Node.js wrapper for libdatachannel: [node-datachannel](https://github.com/murat-dogan/node-datachannel)
+- Unity wrapper for Windows 10 and Hololens: [datachannel-unity](https://github.com/hanseuljun/datachannel-unity)
+- WebAssembly wrapper compatible with libdatachannel: [datachannel-wasm](https://github.com/paullouisageneau/datachannel-wasm)
 

examples/README.md

@@ -7,6 +7,8 @@ This directory contains different WebRTC clients and compatible WebSocket + JSON
 - [signaling-server-python](signaling-server-python) contains a similar signaling server in Python
 - [signaling-server-rust](signaling-server-rust) contains a similar signaling server in Rust (see [lerouxrgd/datachannel-rs](https://github.com/lerouxrgd/datachannel-rs) for Rust wrappers)
 
+- [media](media) is a copy/paste demo to send the webcam from your browser into gstreamer.
+
 Additionally, it contains two debugging tools for libdatachannel with copy-pasting as signaling:
 - [copy-paste](copy-paste) using the C++ API
 - [copy-paste-capi](copy-paste-capi) using the C API

examples/client/CMakeLists.txt

@@ -3,7 +3,12 @@ if(POLICY CMP0079)
 	cmake_policy(SET CMP0079 NEW)
 endif()
 
-add_executable(datachannel-client main.cpp)
+if(WIN32)
+add_executable(datachannel-client main.cpp parse_cl.cpp parse_cl.h getopt.cpp getopt.h)
+target_compile_definitions(datachannel-client PUBLIC STATIC_GETOPT)
+else()
+add_executable(datachannel-client main.cpp parse_cl.cpp parse_cl.h)
+endif()
 set_target_properties(datachannel-client PROPERTIES
 	CXX_STANDARD 17
 	OUTPUT_NAME client)

examples/client/getopt.cpp

@@ -0,0 +1,513 @@
+/* Getopt for Microsoft C
+This code is a modification of the Free Software Foundation, Inc.
+Getopt library for parsing command line argument the purpose was
+to provide a Microsoft Visual C friendly derivative. This code
+provides functionality for both Unicode and Multibyte builds.
+
+Date: 02/03/2011 - Ludvik Jerabek - Initial Release
+Version: 1.0
+Comment: Supports getopt, getopt_long, and getopt_long_only
+and POSIXLY_CORRECT environment flag
+License: LGPL
+
+Revisions:
+
+02/03/2011 - Ludvik Jerabek - Initial Release
+02/20/2011 - Ludvik Jerabek - Fixed compiler warnings at Level 4
+07/05/2011 - Ludvik Jerabek - Added no_argument, required_argument, optional_argument defs
+08/03/2011 - Ludvik Jerabek - Fixed non-argument runtime bug which caused runtime exception
+08/09/2011 - Ludvik Jerabek - Added code to export functions for DLL and LIB
+02/15/2012 - Ludvik Jerabek - Fixed _GETOPT_THROW definition missing in implementation file
+08/01/2012 - Ludvik Jerabek - Created separate functions for char and wchar_t characters so single dll can do both unicode and ansi
+10/15/2012 - Ludvik Jerabek - Modified to match latest GNU features
+06/19/2015 - Ludvik Jerabek - Fixed maximum option limitation caused by option_a (255) and option_w (65535) structure val variable
+24/10/2020 - Paul-Louis Ageneau - Removed Unicode version
+
+**DISCLAIMER**
+THIS MATERIAL IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
+EITHER EXPRESS OR IMPLIED, INCLUDING, BUT Not LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+PURPOSE, OR NON-INFRINGEMENT. SOME JURISDICTIONS DO NOT ALLOW THE
+EXCLUSION OF IMPLIED WARRANTIES, SO THE ABOVE EXCLUSION MAY NOT
+APPLY TO YOU. IN NO EVENT WILL I BE LIABLE TO ANY PARTY FOR ANY
+DIRECT, INDIRECT, SPECIAL OR OTHER CONSEQUENTIAL DAMAGES FOR ANY
+USE OF THIS MATERIAL INCLUDING, WITHOUT LIMITATION, ANY LOST
+PROFITS, BUSINESS INTERRUPTION, LOSS OF PROGRAMS OR OTHER DATA ON
+YOUR INFORMATION HANDLING SYSTEM OR OTHERWISE, EVEN If WE ARE
+EXPRESSLY ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+*/
+
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <malloc.h>
+#include "getopt.h"
+
+#ifdef __cplusplus
+	#define _GETOPT_THROW throw()
+#else
+	#define _GETOPT_THROW
+#endif
+
+int optind = 1;
+int opterr = 1;
+int optopt = '?';
+enum ENUM_ORDERING { REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER };
+
+static struct _getopt_data_a
+{
+	int optind;
+	int opterr;
+	int optopt;
+	char *optarg;
+	int __initialized;
+	char *__nextchar;
+	enum ENUM_ORDERING __ordering;
+	int __posixly_correct;
+	int __first_nonopt;
+	int __last_nonopt;
+} getopt_data_a;
+char *optarg_a;
+
+static void exchange_a(char **argv, struct _getopt_data_a *d)
+{
+	int bottom = d->__first_nonopt;
+	int middle = d->__last_nonopt;
+	int top = d->optind;
+	char *tem;
+	while (top > middle && middle > bottom)
+	{
+		if (top - middle > middle - bottom)
+		{
+			int len = middle - bottom;
+			int i;
+			for (i = 0; i < len; i++)
+			{
+				tem = argv[bottom + i];
+				argv[bottom + i] = argv[top - (middle - bottom) + i];
+				argv[top - (middle - bottom) + i] = tem;
+			}
+			top -= len;
+		}
+		else
+		{
+			int len = top - middle;
+			int i;
+			for (i = 0; i < len; i++)
+			{
+				tem = argv[bottom + i];
+				argv[bottom + i] = argv[middle + i];
+				argv[middle + i] = tem;
+			}
+			bottom += len;
+		}
+	}
+	d->__first_nonopt += (d->optind - d->__last_nonopt);
+	d->__last_nonopt = d->optind;
+}
+static const char *_getopt_initialize_a (const char *optstring, struct _getopt_data_a *d, int posixly_correct)
+{
+	d->__first_nonopt = d->__last_nonopt = d->optind;
+	d->__nextchar = NULL;
+	d->__posixly_correct = posixly_correct | !!getenv("POSIXLY_CORRECT");
+	if (optstring[0] == '-')
+	{
+		d->__ordering = RETURN_IN_ORDER;
+		++optstring;
+	}
+	else if (optstring[0] == '+')
+	{
+		d->__ordering = REQUIRE_ORDER;
+		++optstring;
+	}
+	else if (d->__posixly_correct)
+		d->__ordering = REQUIRE_ORDER;
+	else
+		d->__ordering = PERMUTE;
+	return optstring;
+}
+int _getopt_internal_r_a (int argc, char *const *argv, const char *optstring, const struct option_a *longopts, int *longind, int long_only, struct _getopt_data_a *d, int posixly_correct)
+{
+	int print_errors = d->opterr;
+	if (argc < 1)
+		return -1;
+	d->optarg = NULL;
+	if (d->optind == 0 || !d->__initialized)
+	{
+		if (d->optind == 0)
+			d->optind = 1;
+		optstring = _getopt_initialize_a (optstring, d, posixly_correct);
+		d->__initialized = 1;
+	}
+	else if (optstring[0] == '-' || optstring[0] == '+')
+		optstring++;
+	if (optstring[0] == ':')
+		print_errors = 0;
+	if (d->__nextchar == NULL || *d->__nextchar == '\0')
+	{
+		if (d->__last_nonopt > d->optind)
+			d->__last_nonopt = d->optind;
+		if (d->__first_nonopt > d->optind)
+			d->__first_nonopt = d->optind;
+		if (d->__ordering == PERMUTE)
+		{
+			if (d->__first_nonopt != d->__last_nonopt && d->__last_nonopt != d->optind)
+				exchange_a ((char **) argv, d);
+			else if (d->__last_nonopt != d->optind)
+				d->__first_nonopt = d->optind;
+			while (d->optind < argc && (argv[d->optind][0] != '-' || argv[d->optind][1] == '\0'))
+				d->optind++;
+			d->__last_nonopt = d->optind;
+		}
+		if (d->optind != argc && !strcmp(argv[d->optind], "--"))
+		{
+			d->optind++;
+			if (d->__first_nonopt != d->__last_nonopt && d->__last_nonopt != d->optind)
+				exchange_a((char **) argv, d);
+			else if (d->__first_nonopt == d->__last_nonopt)
+				d->__first_nonopt = d->optind;
+			d->__last_nonopt = argc;
+			d->optind = argc;
+		}
+		if (d->optind == argc)
+		{
+			if (d->__first_nonopt != d->__last_nonopt)
+				d->optind = d->__first_nonopt;
+			return -1;
+		}
+		if ((argv[d->optind][0] != '-' || argv[d->optind][1] == '\0'))
+		{
+			if (d->__ordering == REQUIRE_ORDER)
+				return -1;
+			d->optarg = argv[d->optind++];
+			return 1;
+		}
+		d->__nextchar = (argv[d->optind] + 1 + (longopts != NULL && argv[d->optind][1] == '-'));
+	}
+	if (longopts != NULL && (argv[d->optind][1] == '-' || (long_only && (argv[d->optind][2] || !strchr(optstring, argv[d->optind][1])))))
+	{
+		char *nameend;
+		unsigned int namelen;
+		const struct option_a *p;
+		const struct option_a *pfound = NULL;
+		struct option_list
+		{
+			const struct option_a *p;
+			struct option_list *next;
+		} *ambig_list = NULL;
+		int exact = 0;
+		int indfound = -1;
+		int option_index;
+		for (nameend = d->__nextchar; *nameend && *nameend != '='; nameend++);
+		namelen = (unsigned int)(nameend - d->__nextchar);
+		for (p = longopts, option_index = 0; p->name; p++, option_index++)
+			if (!strncmp(p->name, d->__nextchar, namelen))
+			{
+				if (namelen == (unsigned int)strlen(p->name))
+				{
+					pfound = p;
+					indfound = option_index;
+					exact = 1;
+					break;
+				}
+				else if (pfound == NULL)
+				{
+					pfound = p;
+					indfound = option_index;
+				}
+				else if (long_only || pfound->has_arg != p->has_arg || pfound->flag != p->flag || pfound->val != p->val)
+				{
+					struct option_list *newp = (struct option_list*)alloca(sizeof(*newp));
+					newp->p = p;
+					newp->next = ambig_list;
+					ambig_list = newp;
+				}
+			}
+			if (ambig_list != NULL && !exact)
+			{
+				if (print_errors)
+				{
+					struct option_list first;
+					first.p = pfound;
+					first.next = ambig_list;
+					ambig_list = &first;
+					fprintf (stderr, "%s: option '%s' is ambiguous; possibilities:", argv[0], argv[d->optind]);
+					do
+					{
+						fprintf (stderr, " '--%s'", ambig_list->p->name);
+						ambig_list = ambig_list->next;
+					}
+					while (ambig_list != NULL);
+					fputc ('\n', stderr);
+				}
+				d->__nextchar += strlen(d->__nextchar);
+				d->optind++;
+				d->optopt = 0;
+				return '?';
+			}
+			if (pfound != NULL)
+			{
+				option_index = indfound;
+				d->optind++;
+				if (*nameend)
+				{
+					if (pfound->has_arg)
+						d->optarg = nameend + 1;
+					else
+					{
+						if (print_errors)
+						{
+							if (argv[d->optind - 1][1] == '-')
+							{
+								fprintf(stderr, "%s: option '--%s' doesn't allow an argument\n",argv[0], pfound->name);
+							}
+							else
+							{
+								fprintf(stderr, "%s: option '%c%s' doesn't allow an argument\n",argv[0], argv[d->optind - 1][0],pfound->name);
+							}
+						}
+						d->__nextchar += strlen(d->__nextchar);
+						d->optopt = pfound->val;
+						return '?';
+					}
+				}
+				else if (pfound->has_arg == 1)
+				{
+					if (d->optind < argc)
+						d->optarg = argv[d->optind++];
+					else
+					{
+						if (print_errors)
+						{
+							fprintf(stderr,"%s: option '--%s' requires an argument\n",argv[0], pfound->name);
+						}
+						d->__nextchar += strlen(d->__nextchar);
+						d->optopt = pfound->val;
+						return optstring[0] == ':' ? ':' : '?';
+					}
+				}
+				d->__nextchar += strlen(d->__nextchar);
+				if (longind != NULL)
+					*longind = option_index;
+				if (pfound->flag)
+				{
+					*(pfound->flag) = pfound->val;
+					return 0;
+				}
+				return pfound->val;
+			}
+			if (!long_only || argv[d->optind][1] == '-' || strchr(optstring, *d->__nextchar) == NULL)
+			{
+				if (print_errors)
+				{
+					if (argv[d->optind][1] == '-')
+					{
+						fprintf(stderr, "%s: unrecognized option '--%s'\n",argv[0], d->__nextchar);
+					}
+					else
+					{
+						fprintf(stderr, "%s: unrecognized option '%c%s'\n",argv[0], argv[d->optind][0], d->__nextchar);
+					}
+				}
+				d->__nextchar = (char *)"";
+				d->optind++;
+				d->optopt = 0;
+				return '?';
+			}
+	}
+	{
+		char c = *d->__nextchar++;
+		char *temp = (char*)strchr(optstring, c);
+		if (*d->__nextchar == '\0')
+			++d->optind;
+		if (temp == NULL || c == ':' || c == ';')
+		{
+			if (print_errors)
+			{
+				fprintf(stderr, "%s: invalid option -- '%c'\n", argv[0], c);
+			}
+			d->optopt = c;
+			return '?';
+		}
+		if (temp[0] == 'W' && temp[1] == ';')
+		{
+			char *nameend;
+			const struct option_a *p;
+			const struct option_a *pfound = NULL;
+			int exact = 0;
+			int ambig = 0;
+			int indfound = 0;
+			int option_index;
+			if (longopts == NULL)
+				goto no_longs;
+			if (*d->__nextchar != '\0')
+			{
+				d->optarg = d->__nextchar;
+				d->optind++;
+			}
+			else if (d->optind == argc)
+			{
+				if (print_errors)
+				{
+					fprintf(stderr,"%s: option requires an argument -- '%c'\n",argv[0], c);
+				}
+				d->optopt = c;
+				if (optstring[0] == ':')
+					c = ':';
+				else
+					c = '?';
+				return c;
+			}
+			else
+				d->optarg = argv[d->optind++];
+			for (d->__nextchar = nameend = d->optarg; *nameend && *nameend != '='; nameend++);
+			for (p = longopts, option_index = 0; p->name; p++, option_index++)
+				if (!strncmp(p->name, d->__nextchar, nameend - d->__nextchar))
+				{
+					if ((unsigned int) (nameend - d->__nextchar) == strlen(p->name))
+					{
+						pfound = p;
+						indfound = option_index;
+						exact = 1;
+						break;
+					}
+					else if (pfound == NULL)
+					{
+						pfound = p;
+						indfound = option_index;
+					}
+					else if (long_only || pfound->has_arg != p->has_arg || pfound->flag != p->flag || pfound->val != p->val)
+						ambig = 1;
+				}
+				if (ambig && !exact)
+				{
+					if (print_errors)
+					{
+						fprintf(stderr, "%s: option '-W %s' is ambiguous\n",argv[0], d->optarg);
+					}
+					d->__nextchar += strlen(d->__nextchar);
+					d->optind++;
+					return '?';
+				}
+				if (pfound != NULL)
+				{
+					option_index = indfound;
+					if (*nameend)
+					{
+						if (pfound->has_arg)
+							d->optarg = nameend + 1;
+						else
+						{
+							if (print_errors)
+							{
+								fprintf(stderr, "%s: option '-W %s' doesn't allow an argument\n",argv[0], pfound->name);
+							}
+							d->__nextchar += strlen(d->__nextchar);
+							return '?';
+						}
+					}
+					else if (pfound->has_arg == 1)
+					{
+						if (d->optind < argc)
+							d->optarg = argv[d->optind++];
+						else
+						{
+							if (print_errors)
+							{
+								fprintf(stderr, "%s: option '-W %s' requires an argument\n",argv[0], pfound->name);
+							}
+							d->__nextchar += strlen(d->__nextchar);
+							return optstring[0] == ':' ? ':' : '?';
+						}
+					}
+					else
+						d->optarg = NULL;
+					d->__nextchar += strlen(d->__nextchar);
+					if (longind != NULL)
+						*longind = option_index;
+					if (pfound->flag)
+					{
+						*(pfound->flag) = pfound->val;
+						return 0;
+					}
+					return pfound->val;
+				}
+no_longs:
+				d->__nextchar = NULL;
+				return 'W';
+		}
+		if (temp[1] == ':')
+		{
+			if (temp[2] == ':')
+			{
+				if (*d->__nextchar != '\0')
+				{
+					d->optarg = d->__nextchar;
+					d->optind++;
+				}
+				else
+					d->optarg = NULL;
+				d->__nextchar = NULL;
+			}
+			else
+			{
+				if (*d->__nextchar != '\0')
+				{
+					d->optarg = d->__nextchar;
+					d->optind++;
+				}
+				else if (d->optind == argc)
+				{
+					if (print_errors)
+					{
+						fprintf(stderr,"%s: option requires an argument -- '%c'\n",argv[0], c);
+					}
+					d->optopt = c;
+					if (optstring[0] == ':')
+						c = ':';
+					else
+						c = '?';
+				}
+				else
+					d->optarg = argv[d->optind++];
+				d->__nextchar = NULL;
+			}
+		}
+		return c;
+	}
+}
+int _getopt_internal_a (int argc, char *const *argv, const char *optstring, const struct option_a *longopts, int *longind, int long_only, int posixly_correct)
+{
+	int result;
+	getopt_data_a.optind = optind;
+	getopt_data_a.opterr = opterr;
+	result = _getopt_internal_r_a (argc, argv, optstring, longopts,longind, long_only, &getopt_data_a,posixly_correct);
+	optind = getopt_data_a.optind;
+	optarg_a = getopt_data_a.optarg;
+	optopt = getopt_data_a.optopt;
+	return result;
+}
+int getopt_a (int argc, char *const *argv, const char *optstring) _GETOPT_THROW
+{
+	return _getopt_internal_a (argc, argv, optstring, (const struct option_a *) 0, (int *) 0, 0, 0);
+}
+int getopt_long_a (int argc, char *const *argv, const char *options, const struct option_a *long_options, int *opt_index) _GETOPT_THROW
+{
+	return _getopt_internal_a (argc, argv, options, long_options, opt_index, 0, 0);
+}
+int getopt_long_only_a (int argc, char *const *argv, const char *options, const struct option_a *long_options, int *opt_index) _GETOPT_THROW
+{
+	return _getopt_internal_a (argc, argv, options, long_options, opt_index, 1, 0);
+}
+int _getopt_long_r_a (int argc, char *const *argv, const char *options, const struct option_a *long_options, int *opt_index, struct _getopt_data_a *d)
+{
+	return _getopt_internal_r_a (argc, argv, options, long_options, opt_index,0, d, 0);
+}
+int _getopt_long_only_r_a (int argc, char *const *argv, const char *options, const struct option_a *long_options, int *opt_index, struct _getopt_data_a *d)
+{
+	return _getopt_internal_r_a (argc, argv, options, long_options, opt_index, 1, d, 0);
+}
+

examples/client/getopt.h

@@ -0,0 +1,115 @@
+/* Getopt for Microsoft C
+This code is a modification of the Free Software Foundation, Inc.
+Getopt library for parsing command line argument the purpose was
+to provide a Microsoft Visual C friendly derivative. This code
+provides functionality for both Unicode and Multibyte builds.
+
+Date: 02/03/2011 - Ludvik Jerabek - Initial Release
+Version: 1.0
+Comment: Supports getopt, getopt_long, and getopt_long_only
+and POSIXLY_CORRECT environment flag
+License: LGPL
+
+Revisions:
+
+02/03/2011 - Ludvik Jerabek - Initial Release
+02/20/2011 - Ludvik Jerabek - Fixed compiler warnings at Level 4
+07/05/2011 - Ludvik Jerabek - Added no_argument, required_argument, optional_argument defs
+08/03/2011 - Ludvik Jerabek - Fixed non-argument runtime bug which caused runtime exception
+08/09/2011 - Ludvik Jerabek - Added code to export functions for DLL and LIB
+02/15/2012 - Ludvik Jerabek - Fixed _GETOPT_THROW definition missing in implementation file
+08/01/2012 - Ludvik Jerabek - Created separate functions for char and wchar_t characters so single dll can do both unicode and ansi
+10/15/2012 - Ludvik Jerabek - Modified to match latest GNU features
+06/19/2015 - Ludvik Jerabek - Fixed maximum option limitation caused by option_a (255) and option_w (65535) structure val variable
+24/10/2020 - Paul-Louis Ageneau - Removed Unicode version
+
+**DISCLAIMER**
+THIS MATERIAL IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
+EITHER EXPRESS OR IMPLIED, INCLUDING, BUT Not LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+PURPOSE, OR NON-INFRINGEMENT. SOME JURISDICTIONS DO NOT ALLOW THE
+EXCLUSION OF IMPLIED WARRANTIES, SO THE ABOVE EXCLUSION MAY NOT
+APPLY TO YOU. IN NO EVENT WILL I BE LIABLE TO ANY PARTY FOR ANY
+DIRECT, INDIRECT, SPECIAL OR OTHER CONSEQUENTIAL DAMAGES FOR ANY
+USE OF THIS MATERIAL INCLUDING, WITHOUT LIMITATION, ANY LOST
+PROFITS, BUSINESS INTERRUPTION, LOSS OF PROGRAMS OR OTHER DATA ON
+YOUR INFORMATION HANDLING SYSTEM OR OTHERWISE, EVEN If WE ARE
+EXPRESSLY ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+*/
+#ifndef __GETOPT_H_
+	#define __GETOPT_H_
+
+	#ifdef _GETOPT_API
+		#undef _GETOPT_API
+	#endif
+
+	#if defined(EXPORTS_GETOPT) && defined(STATIC_GETOPT)
+		#error "The preprocessor definitions of EXPORTS_GETOPT and STATIC_GETOPT can only be used individually"
+	#elif defined(STATIC_GETOPT)
+		#pragma message("Warning static builds of getopt violate the Lesser GNU Public License")
+		#define _GETOPT_API
+	#elif defined(EXPORTS_GETOPT)
+		#pragma message("Exporting getopt library")
+		#define _GETOPT_API __declspec(dllexport)
+	#else
+		#pragma message("Importing getopt library")
+		#define _GETOPT_API __declspec(dllimport)
+	#endif
+
+	// Change behavior for C\C++
+	#ifdef __cplusplus
+		#define _BEGIN_EXTERN_C extern "C" {
+		#define _END_EXTERN_C }
+		#define _GETOPT_THROW throw()
+	#else
+		#define _BEGIN_EXTERN_C
+		#define _END_EXTERN_C
+		#define _GETOPT_THROW
+	#endif
+
+	// Standard GNU options
+	#define	null_argument		0	/*Argument Null*/
+	#define	no_argument			0	/*Argument Switch Only*/
+	#define required_argument	1	/*Argument Required*/
+	#define optional_argument	2	/*Argument Optional*/	
+
+	// Shorter Options
+	#define ARG_NULL	0	/*Argument Null*/
+	#define ARG_NONE	0	/*Argument Switch Only*/
+	#define ARG_REQ		1	/*Argument Required*/
+	#define ARG_OPT		2	/*Argument Optional*/
+
+	#include <string.h>
+
+_BEGIN_EXTERN_C
+
+	extern _GETOPT_API int optind;
+	extern _GETOPT_API int opterr;
+	extern _GETOPT_API int optopt;
+
+	struct option_a
+	{
+		const char* name;
+		int has_arg;
+		int *flag;
+		int val;
+	};
+	extern _GETOPT_API char *optarg_a;
+	extern _GETOPT_API int getopt_a(int argc, char *const *argv, const char *optstring) _GETOPT_THROW;
+	extern _GETOPT_API int getopt_long_a(int argc, char *const *argv, const char *options, const struct option_a *long_options, int *opt_index) _GETOPT_THROW;
+	extern _GETOPT_API int getopt_long_only_a(int argc, char *const *argv, const char *options, const struct option_a *long_options, int *opt_index) _GETOPT_THROW;
+
+_END_EXTERN_C
+
+	#undef _BEGIN_EXTERN_C
+	#undef _END_EXTERN_C
+	#undef _GETOPT_THROW
+	#undef _GETOPT_API
+
+	#define getopt getopt_a
+	#define getopt_long getopt_long_a
+	#define getopt_long_only getopt_long_only_a
+	#define option option_a
+	#define optarg optarg_a
+
+#endif  // __GETOPT_H_

examples/client/main.cpp

@@ -5,6 +5,7 @@
  * Copyright (c) 2020 Will Munn
  * Copyright (c) 2020 Nico Chatzi
  * Copyright (c) 2020 Lara Mackey
+ * Copyright (c) 2020 Erik Cota-Robles
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -29,7 +30,10 @@
 #include <memory>
 #include <random>
 #include <thread>
+#include <future>
+#include <stdexcept>
 #include <unordered_map>
+#include "parse_cl.h"
 
 using namespace rtc;
 using namespace std;
@@ -43,29 +47,57 @@ unordered_map<string, shared_ptr<PeerConnection>> peerConnectionMap;
 unordered_map<string, shared_ptr<DataChannel>> dataChannelMap;
 
 string localId;
+bool echoDataChannelMessages = false;
 
 shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
                                                 weak_ptr<WebSocket> wws, string id);
+void printReceived(bool echoed, string id, string type, size_t length);
 string randomId(size_t length);
 
-int main(int argc, char **argv) {
+
+int main(int argc, char **argv) try {
+	auto params = std::make_unique<Cmdline>(argc, argv);
+
 	rtc::InitLogger(LogLevel::Debug);
 
 	Configuration config;
-	config.iceServers.emplace_back("stun:stun.l.google.com:19302"); // change to your STUN server
+	string stunServer = "";
+	if (params->noStun()) {
+		cout << "No STUN server is configured. Only local hosts and public IP addresses supported." << endl;
+	} else {
+		if (params->stunServer().substr(0,5).compare("stun:") != 0) {
+			stunServer = "stun:";
+		}
+		stunServer += params->stunServer() + ":" + to_string(params->stunPort());
+		cout << "Stun server is " << stunServer << endl;
+		config.iceServers.emplace_back(stunServer);
+	}
 
 	localId = randomId(4);
 	cout << "The local ID is: " << localId << endl;
 
+	echoDataChannelMessages = params->echoDataChannelMessages();
+	cout << "Received data channel messages will be "
+	     << (echoDataChannelMessages ? "echoed back to sender" : "printed to stdout") << endl;
+
 	auto ws = make_shared<WebSocket>();
 
-	ws->onOpen([]() { cout << "WebSocket connected, signaling ready" << endl; });
+	std::promise<void> wsPromise;
+	auto wsFuture = wsPromise.get_future();
+	
+	ws->onOpen([&wsPromise]() { 
+		cout << "WebSocket connected, signaling ready" << endl;
+		wsPromise.set_value();
+	});
+
+	ws->onError([&wsPromise](string s) { 
+		cout << "WebSocket error" << endl;
+		wsPromise.set_exception(std::make_exception_ptr(std::runtime_error(s)));
+	});
 	
 	ws->onClosed([]() { cout << "WebSocket closed" << endl; });
 	
-	ws->onError([](const string &error) { cout << "WebSocket failed: " << error << endl; });
-
-	ws->onMessage([&](const variant<binary, string> &data) {
+	ws->onMessage([&](variant<binary, string> data) {
 		if (!holds_alternative<string>(data))
 			return;
 
@@ -101,15 +133,17 @@ int main(int argc, char **argv) {
 		}
 	});
 
-	const string url = "ws://localhost:8000/" + localId;
+	string wsPrefix = "";
+	if (params->webSocketServer().substr(0,5).compare("ws://") != 0) {
+		wsPrefix = "ws://";
+	}
+	const string url = wsPrefix + params->webSocketServer() + ":" +
+		to_string(params->webSocketPort()) + "/" + localId;
+	cout << "Url is " << url << endl;
 	ws->open(url);
 	
 	cout << "Waiting for signaling to be connected..." << endl;
-	while (!ws->isOpen()) {
-		if (ws->isClosed())
-			return 1;
-		this_thread::sleep_for(100ms);
-	}
+	wsFuture.get();
 
 	while (true) {
 		string id;
@@ -137,16 +171,23 @@ int main(int argc, char **argv) {
 
 		dc->onClosed([id]() { cout << "DataChannel from " << id << " closed" << endl; });
 
-		dc->onMessage([id](const variant<binary, string> &message) {
-			if (!holds_alternative<string>(message))
-				return;
-
+		dc->onMessage([id, wdc = make_weak_ptr(dc)](const variant<binary, string> &message) {
+			static bool firstMessage = true;
+			if (holds_alternative<string>(message) && (!echoDataChannelMessages || firstMessage)) {
 				cout << "Message from " << id << " received: " << get<string>(message) << endl;
+				firstMessage = false;
+			} else if (echoDataChannelMessages) {
+				bool echoed = false;
+				if (auto dc = wdc.lock()) {
+					dc->send(message);
+					echoed = true;
+				}
+				printReceived(echoed, id, (holds_alternative<string>(message) ? "text" : "binary"),
+				      get<string>(message).length());
+			}
 		});
 
 		dataChannelMap.emplace(id, dc);
-
-		this_thread::sleep_for(1s);
 	}
 
 	cout << "Cleaning up..." << endl;
@@ -154,6 +195,12 @@ int main(int argc, char **argv) {
 	dataChannelMap.clear();
 	peerConnectionMap.clear();
 	return 0;
+
+} catch (const std::exception &e) {
+	std::cout << "Error: " << e.what() << std::endl;
+	dataChannelMap.clear();
+	peerConnectionMap.clear();
+	return -1;
 }
 
 // Create and setup a PeerConnection
@@ -166,7 +213,7 @@ shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
 	pc->onGatheringStateChange(
 	    [](PeerConnection::GatheringState state) { cout << "Gathering State: " << state << endl; });
 
-	pc->onLocalDescription([wws, id](const Description &description) {
+	pc->onLocalDescription([wws, id](Description description) {
 		json message = {
 		    {"id", id}, {"type", description.typeString()}, {"description", string(description)}};
 
@@ -174,7 +221,7 @@ shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
 			ws->send(message.dump());
 	});
 
-	pc->onLocalCandidate([wws, id](const Candidate &candidate) {
+	pc->onLocalCandidate([wws, id](Candidate candidate) {
 		json message = {{"id", id},
 		                {"type", "candidate"},
 		                {"candidate", string(candidate)},
@@ -190,11 +237,20 @@ shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
 
 		dc->onClosed([id]() { cout << "DataChannel from " << id << " closed" << endl; });
 
-		dc->onMessage([id](const variant<binary, string> &message) {
-			if (!holds_alternative<string>(message))
-				return;
-
+		dc->onMessage([id, wdc = make_weak_ptr(dc)](const variant<binary, string> &message) {
+			static bool firstMessage = true;
+			if (holds_alternative<string>(message) && (!echoDataChannelMessages || firstMessage)) {
 				cout << "Message from " << id << " received: " << get<string>(message) << endl;
+				firstMessage = false;
+			} else if (echoDataChannelMessages) {
+				bool echoed = false;
+				if (auto dc = wdc.lock()) {
+					dc->send(message);
+					echoed = true;
+				}
+				printReceived(echoed, id, (holds_alternative<string>(message) ? "text" : "binary"),
+						get<string>(message).length());
+			}
 		});
 
 		dc->send("Hello from " + localId);
@@ -206,6 +262,20 @@ shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
 	return pc;
 };
 
+// Helper function to print received pings
+void printReceived(bool echoed, string id, string type, size_t length) {
+	static long count = 0;
+	static long freq = 100;
+	if (!(++count%freq)) {
+		cout << "Received " << count << " pings in total from " << id << ", most recent of type "
+		     << type << " and " << (echoed ? "" : "un") << "successfully echoed most recent ping of size "
+		     << length << " back to " << id << endl;
+		if (count >= (freq * 10) && freq < 1000000) {
+			freq *= 10;
+		}
+	}
+}
+
 // Helper function to generate a random ID
 string randomId(size_t length) {
 	static const string characters(

examples/client/parse_cl.cpp

@@ -0,0 +1,182 @@
+/******************************************************************************
+**
+** parse_cl.cpp
+**
+** Thu Aug  6 19:42:25 2020
+** Linux 5.4.0-42-generic (#46-Ubuntu SMP Fri Jul 10 00:24:02 UTC 2020) x86_64
+** cerik@Erik-VBox-Ubuntu (Erik Cota-Robles)
+**
+** Copyright (c) 2020 Erik Cota-Robles
+**
+** Definition of command line parser class
+**
+** Automatically created by genparse v0.9.3
+**
+** See http://genparse.sourceforge.net for details and updates
+**
+**
+******************************************************************************/
+
+#include <stdlib.h>
+
+#if defined(_WIN32) || defined(WIN32)
+#include "getopt.h"
+#else
+#include <getopt.h>
+#endif
+
+#include "parse_cl.h"
+
+/*----------------------------------------------------------------------------
+**
+** Cmdline::Cmdline ()
+**
+** Constructor method.
+**
+**--------------------------------------------------------------------------*/
+
+Cmdline::Cmdline (int argc, char *argv[]) // ISO C++17 not allowed: throw (std::string )
+{
+  extern char *optarg;
+  extern int optind;
+  int c;
+
+  static struct option long_options[] =
+  {
+    {"echo", no_argument, NULL, 'e'},
+    {"noStun", no_argument, NULL, 'n'},
+    {"stunServer", required_argument, NULL, 's'},
+    {"stunPort", required_argument, NULL, 't'},
+    {"webSocketServer", required_argument, NULL, 'w'},
+    {"webSocketPort", required_argument, NULL, 'x'},
+    {"help", no_argument, NULL, 'h'},
+    {"version", no_argument, NULL, 'v'},
+    {NULL, 0, NULL, 0}
+  };
+
+  _program_name += argv[0];
+
+  /* default values */
+  _e = false;
+  _n = false;
+  _s = "stun.l.google.com";
+  _t = 19302;
+  _w = "localhost";
+  _x = 8000;
+  _h = false;
+  _v = false;
+
+  optind = 0;
+  while ((c = getopt_long (argc, argv, "s:t:w:x:enhv", long_options, &optind)) != - 1)
+    {
+      switch (c)
+        {
+        case 'e': 
+          _e = true;
+          break;
+
+        case 'n': 
+          _n = true;
+          break;
+
+        case 's': 
+          _s = optarg;
+          break;
+
+        case 't': 
+          _t = atoi (optarg);
+          if (_t < 0)
+            {
+              std::string err;
+              err += "parameter range error: t must be >= 0";
+              throw (std::range_error(err));
+            }
+          if (_t > 65535)
+            {
+              std::string err;
+              err += "parameter range error: t must be <= 65535";
+              throw (std::range_error(err));
+            }
+          break;
+
+        case 'w': 
+          _w = optarg;
+          break;
+
+        case 'x': 
+          _x = atoi (optarg);
+          if (_x < 0)
+            {
+              std::string err;
+              err += "parameter range error: x must be >= 0";
+              throw (std::range_error(err));
+            }
+          if (_x > 65535)
+            {
+              std::string err;
+              err += "parameter range error: x must be <= 65535";
+              throw (std::range_error(err));
+            }
+          break;
+
+        case 'h': 
+          _h = true;
+          this->usage (EXIT_SUCCESS);
+          break;
+
+        case 'v': 
+          _v = true;
+          this->version (EXIT_SUCCESS);
+          break;
+
+        default:
+          this->usage (EXIT_FAILURE);
+
+        }
+    } /* while */
+
+  _optind = optind;
+}
+
+/*----------------------------------------------------------------------------
+**
+** Cmdline::usage () and version()
+**
+** Print out usage (or version) information, then exit.
+**
+**--------------------------------------------------------------------------*/
+
+void Cmdline::usage (int status)
+{
+  if (status != EXIT_SUCCESS)
+    std::cerr << "Try `" << _program_name << " --help' for more information.\n";
+  else
+    {
+      std::cout << "\
+usage: " << _program_name << " [ -enstwxhv ] \n\
+libdatachannel client implementing WebRTC Data Channels with WebSocket signaling\n\
+   [ -e ] [ --echo ] (type=FLAG)\n\
+          Echo data channel messages back to sender rather than putting to stdout.\n\
+   [ -n ] [ --noStun ] (type=FLAG)\n\
+          Do NOT use a stun server (overrides -s and -t).\n\
+   [ -s ] [ --stunServer ] (type=STRING, default=stun.l.google.com)\n\
+          Stun server URL or IP address.\n\
+   [ -t ] [ --stunPort ] (type=INTEGER, range=0...65535, default=19302)\n\
+          Stun server port.\n\
+   [ -w ] [ --webSocketServer ] (type=STRING, default=localhost)\n\
+          Web socket server URL or IP address.\n\
+   [ -x ] [ --webSocketPort ] (type=INTEGER, range=0...65535, default=8000)\n\
+          Web socket server port.\n\
+   [ -h ] [ --help ] (type=FLAG)\n\
+          Display this help and exit.\n\
+   [ -v ] [ --version ] (type=FLAG)\n\
+          Output version information and exit.\n";
+    }
+  exit (status);
+}
+
+void Cmdline::version (int status)
+{
+  std::cout << _program_name << " v0.5\n";
+  exit (status);
+}

examples/client/parse_cl.h

@@ -0,0 +1,74 @@
+/******************************************************************************
+**
+** parse_cl.h
+**
+** Thu Aug  6 19:42:25 2020
+** Linux 5.4.0-42-generic (#46-Ubuntu SMP Fri Jul 10 00:24:02 UTC 2020) x86_64
+** cerik@Erik-VBox-Ubuntu (Erik Cota-Robles)
+**
+** Copyright (c) 2020 Erik Cota-Robles
+**
+** Header file for command line parser class
+**
+** Automatically created by genparse v0.9.3
+**
+** See http://genparse.sourceforge.net for details and updates
+**
+******************************************************************************/
+
+#ifndef CMDLINE_H
+#define CMDLINE_H
+
+#include <iostream>
+#include <string>
+
+/*----------------------------------------------------------------------------
+**
+** class Cmdline
+**
+** command line parser class
+**
+**--------------------------------------------------------------------------*/
+
+class Cmdline
+{
+private:
+  /* parameters */
+  bool _e;
+  bool _n;
+  std::string _s;
+  int _t;
+  std::string _w;
+  int _x;
+  bool _h;
+  bool _v;
+
+  /* other stuff to keep track of */
+  std::string _program_name;
+  int _optind;
+
+public:
+  /* constructor and destructor */
+  Cmdline (int, char **); // ISO C++17 not allowed: throw (std::string);
+  ~Cmdline (){}
+
+  /* usage function */
+  void usage (int status);
+
+  /* version function */
+  void version (int status);
+
+  /* return next (non-option) parameter */
+  int next_param () { return _optind; }
+
+  bool echoDataChannelMessages () const { return _e; }
+  bool noStun () const { return _n; }
+  std::string stunServer () const { return _s; }
+  int stunPort () const { return _t; }
+  std::string webSocketServer () const { return _w; }
+  int webSocketPort () const { return _x; }
+  bool h () const { return _h; }
+  bool v () const { return _v; }
+};
+
+#endif

examples/copy-paste-capi/answerer.c

@@ -41,16 +41,16 @@ typedef struct {
 	bool connected;
 } Peer;
 
-static void dataChannelCallback(int dc, void *ptr);
-static void descriptionCallback(const char *sdp, const char *type, void *ptr);
-static void candidateCallback(const char *cand, const char *mid, void *ptr);
-static void stateChangeCallback(rtcState state, void *ptr);
-static void gatheringStateCallback(rtcGatheringState state, void *ptr);
-static void closedCallback(void *ptr);
-static void messageCallback(const char *message, int size, void *ptr);
+static void RTC_API dataChannelCallback(int pc, int dc, void *ptr);
+static void RTC_API descriptionCallback(int pc, const char *sdp, const char *type, void *ptr);
+static void RTC_API candidateCallback(int pc, const char *cand, const char *mid, void *ptr);
+static void RTC_API stateChangeCallback(int pc, rtcState state, void *ptr);
+static void RTC_API gatheringStateCallback(int pc, rtcGatheringState state, void *ptr);
+static void RTC_API closedCallback(int id, void *ptr);
+static void RTC_API messageCallback(int id, const char *message, int size, void *ptr);
 static void deletePeer(Peer *peer);
 
-char* state_print(rtcState state);
+char *state_print(rtcState state);
 char *rtcGatheringState_print(rtcGatheringState state);
 
 int all_space(const char *str);
@@ -88,7 +88,8 @@ int main(int argc, char **argv) {
 	bool exit = false;
 	while (!exit) {
 		printf("\n");
-                printf("***************************************************************************************\n");
+		printf("***********************************************************************************"
+		       "****\n");
 		printf("* 0: Exit /"
 		       " 1: Enter remote description /"
 		       " 2: Enter remote candidate /"
@@ -118,26 +119,24 @@ int main(int argc, char **argv) {
 			char *line = NULL;
 			size_t len = 0;
 			size_t read = 0;
-                        char *sdp = (char*) malloc(sizeof(char));
+			char *sdp = (char *)malloc(sizeof(char));
 			while ((read = getline(&line, &len, stdin)) != -1 && !all_space(line)) {
-                                sdp = (char*) realloc (sdp,(strlen(sdp)+1) +strlen(line)+1);
+				sdp = (char *)realloc(sdp, (strlen(sdp) + 1) + strlen(line) + 1);
 				strcat(sdp, line);
-
 			}
-                        printf("%s\n",sdp);
+			printf("%s\n", sdp);
 			rtcSetRemoteDescription(peer->pc, sdp, "offer");
 			free(sdp);
 			free(line);
 			break;
-
 		}
 		case 2: {
 			// Parse Candidate
 			printf("[Candidate]: ");
-                        char* candidate = NULL;
+			char *candidate = NULL;
 			size_t candidate_size = 0;
 
-                        if(getline(&candidate, &candidate_size, stdin)) {
+			if (getline(&candidate, &candidate_size, stdin)) {
 				rtcAddRemoteCandidate(peer->pc, candidate, "0");
 				free(candidate);
 
@@ -150,15 +149,15 @@ int main(int argc, char **argv) {
 		}
 		case 3: {
 			// Send Message
-                        if(!peer->connected) {
+			if (!peer->connected) {
 				printf("** Channel is not Open **");
 				break;
 			}
 			printf("[Message]: ");
-                        char* message = NULL;
+			char *message = NULL;
 			size_t message_size = 0;
 
-                        if(getline(&message, &message_size, stdin)) {
+			if (getline(&message, &message_size, stdin)) {
 				rtcSendMessage(peer->dc, message, -1);
 				free(message);
 			} else {
@@ -169,7 +168,7 @@ int main(int argc, char **argv) {
 		}
 		case 4: {
 			// Connection Info
-                        if(!peer->connected) {
+			if (!peer->connected) {
 				printf("** Channel is not Open **");
 				break;
 			}
@@ -194,35 +193,32 @@ int main(int argc, char **argv) {
 	return 0;
 }
 
-static void descriptionCallback(const char *sdp, const char *type, void *ptr) {
-        // Peer *peer = (Peer *)ptr;
+static void RTC_API descriptionCallback(int pc, const char *sdp, const char *type, void *ptr) {
 	printf("Description %s:\n%s\n", "answerer", sdp);
 }
 
-static void candidateCallback(const char *cand, const char *mid, void *ptr) {
-        // Peer *peer = (Peer *)ptr;
+static void RTC_API candidateCallback(int pc, const char *cand, const char *mid, void *ptr) {
 	printf("Candidate %s: %s\n", "answerer", cand);
-
 }
 
-static void stateChangeCallback(rtcState state, void *ptr) {
+static void RTC_API stateChangeCallback(int pc, rtcState state, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->state = state;
 	printf("State %s: %s\n", "answerer", state_print(state));
 }
 
-static void gatheringStateCallback(rtcGatheringState state, void *ptr) {
+static void RTC_API gatheringStateCallback(int pc, rtcGatheringState state, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->gatheringState = state;
 	printf("Gathering state %s: %s\n", "answerer", rtcGatheringState_print(state));
 }
 
-static void closedCallback(void *ptr) {
+static void RTC_API closedCallback(int id, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->connected = false;
 }
 
-static void messageCallback(const char *message, int size, void *ptr) {
+static void RTC_API messageCallback(int id, const char *message, int size, void *ptr) {
 	if (size < 0) { // negative size indicates a null-terminated string
 		printf("Message %s: %s\n", "answerer", message);
 	} else {
@@ -230,6 +226,17 @@ static void messageCallback(const char *message, int size, void *ptr) {
 	}
 }
 
+static void RTC_API dataChannelCallback(int pc, int dc, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->dc = dc;
+	peer->connected = true;
+	rtcSetClosedCallback(dc, closedCallback);
+	rtcSetMessageCallback(dc, messageCallback);
+	char buffer[256];
+	if (rtcGetDataChannelLabel(dc, buffer, 256) >= 0)
+		printf("DataChannel %s: Received with label \"%s\"\n", "answerer", buffer);
+}
+
 static void deletePeer(Peer *peer) {
 	if (peer) {
 		if (peer->dc)
@@ -240,17 +247,6 @@ static void deletePeer(Peer *peer) {
 	}
 }
 
-static void dataChannelCallback(int dc, void *ptr) {
-        Peer *peer = (Peer *)ptr;
-        peer->dc = dc;
-        peer->connected = true;
-        rtcSetClosedCallback(dc, closedCallback);
-        rtcSetMessageCallback(dc, messageCallback);
-        char buffer[256];
-        if (rtcGetDataChannelLabel(dc, buffer, 256) >= 0)
-                printf("DataChannel %s: Received with label \"%s\"\n", "answerer", buffer);
-}
-
 char *state_print(rtcState state) {
 	char *str = NULL;
 	switch (state) {

examples/copy-paste-capi/offerer.c

@@ -41,13 +41,13 @@ typedef struct {
 	bool connected;
 } Peer;
 
-static void descriptionCallback(const char *sdp, const char *type, void *ptr);
-static void candidateCallback(const char *cand, const char *mid, void *ptr);
-static void stateChangeCallback(rtcState state, void *ptr);
-static void gatheringStateCallback(rtcGatheringState state, void *ptr);
-static void openCallback(void *ptr);
-static void closedCallback(void *ptr);
-static void messageCallback(const char *message, int size, void *ptr);
+static void RTC_API descriptionCallback(int pc, const char *sdp, const char *type, void *ptr);
+static void RTC_API candidateCallback(int pc, const char *cand, const char *mid, void *ptr);
+static void RTC_API stateChangeCallback(int pc, rtcState state, void *ptr);
+static void RTC_API gatheringStateCallback(int pc, rtcGatheringState state, void *ptr);
+static void RTC_API openCallback(int id, void *ptr);
+static void RTC_API closedCallback(int id, void *ptr);
+static void RTC_API messageCallback(int id, const char *message, int size, void *ptr);
 static void deletePeer(Peer *peer);
 
 char *state_print(rtcState state);
@@ -55,7 +55,7 @@ char *rtcGatheringState_print(rtcGatheringState state);
 
 int all_space(const char *str);
 
-int main(int argc, char **argv){
+int main(int argc, char **argv) {
 	rtcInitLogger(RTC_LOG_DEBUG, NULL);
 
 	// Create peer
@@ -79,7 +79,7 @@ int main(int argc, char **argv){
 	rtcSetStateChangeCallback(peer->pc, stateChangeCallback);
 	rtcSetGatheringStateChangeCallback(peer->pc, gatheringStateCallback);
 
-        // Since this is the offere, we will create a datachannel
+	// Since we are the offerer, we will create a datachannel
 	peer->dc = rtcCreateDataChannel(peer->pc, "test");
 	rtcSetOpenCallback(peer->dc, openCallback);
 	rtcSetClosedCallback(peer->dc, closedCallback);
@@ -91,7 +91,8 @@ int main(int argc, char **argv){
 	while (!exit) {
 
 		printf("\n");
-                printf("***************************************************************************************\n");
+		printf("***********************************************************************************"
+		       "****\n");
 		printf("* 0: Exit /"
 		       " 1: Enter remote description /"
 		       " 2: Enter remote candidate /"
@@ -119,53 +120,49 @@ int main(int argc, char **argv){
 			// Parse Description
 			printf("[Description]: ");
 
-
 			char *line = NULL;
 			size_t len = 0;
 			size_t read = 0;
-                        char *sdp = (char*) malloc(sizeof(char));
+			char *sdp = (char *)malloc(sizeof(char));
 			while ((read = getline(&line, &len, stdin)) != -1 && !all_space(line)) {
-                                sdp = (char*) realloc (sdp,(strlen(sdp)+1) +strlen(line)+1);
+				sdp = (char *)realloc(sdp, (strlen(sdp) + 1) + strlen(line) + 1);
 				strcat(sdp, line);
-
 			}
-                        printf("%s\n",sdp);
+			printf("%s\n", sdp);
 			rtcSetRemoteDescription(peer->pc, sdp, "answer");
 			free(sdp);
 			free(line);
 			break;
-
 		}
 		case 2: {
 			// Parse Candidate
 			printf("[Candidate]: ");
-                        char* candidate = NULL;
+			char *candidate = NULL;
 			size_t candidate_size = 0;
-                        if(getline(&candidate, &candidate_size, stdin)) {
+			if (getline(&candidate, &candidate_size, stdin)) {
 				rtcAddRemoteCandidate(peer->pc, candidate, "0");
 				free(candidate);
 
-                        }else {
+			} else {
 				printf("Error reading line\n");
 				break;
 			}
 
-
 			break;
 		}
 		case 3: {
 			// Send Message
-                        if(!peer->connected) {
+			if (!peer->connected) {
 				printf("** Channel is not Open **");
 				break;
 			}
 			printf("[Message]: ");
-                        char* message = NULL;
+			char *message = NULL;
 			size_t message_size = 0;
-                        if(getline(&message, &message_size, stdin)) {
+			if (getline(&message, &message_size, stdin)) {
 				rtcSendMessage(peer->dc, message, -1);
 				free(message);
-                        }else {
+			} else {
 				printf("Error reading line\n");
 				break;
 			}
@@ -174,7 +171,7 @@ int main(int argc, char **argv){
 		}
 		case 4: {
 			// Connection Info
-                        if(!peer->connected) {
+			if (!peer->connected) {
 				printf("** Channel is not Open **");
 				break;
 			}
@@ -199,44 +196,40 @@ int main(int argc, char **argv){
 	return 0;
 }
 
-static void descriptionCallback(const char *sdp, const char *type, void *ptr) {
-        // Peer *peer = (Peer *)ptr;
+static void RTC_API descriptionCallback(int pc, const char *sdp, const char *type, void *ptr) {
 	printf("Description %s:\n%s\n", "offerer", sdp);
 }
 
-static void candidateCallback(const char *cand, const char *mid, void *ptr) {
-        // Peer *peer = (Peer *)ptr;
+static void RTC_API candidateCallback(int pc, const char *cand, const char *mid, void *ptr) {
 	printf("Candidate %s: %s\n", "offerer", cand);
-
 }
 
-static void stateChangeCallback(rtcState state, void *ptr) {
+static void RTC_API stateChangeCallback(int pc, rtcState state, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->state = state;
 	printf("State %s: %s\n", "offerer", state_print(state));
 }
 
-static void gatheringStateCallback(rtcGatheringState state, void *ptr) {
+static void RTC_API gatheringStateCallback(int pc, rtcGatheringState state, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->gatheringState = state;
 	printf("Gathering state %s: %s\n", "offerer", rtcGatheringState_print(state));
 }
 
-static void openCallback(void *ptr) {
+static void RTC_API openCallback(int id, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->connected = true;
 	char buffer[256];
 	if (rtcGetDataChannelLabel(peer->dc, buffer, 256) >= 0)
-                printf("DataChannel %s: Received with label \"%s\"\n","offerer", buffer);
+		printf("DataChannel %s: Received with label \"%s\"\n", "offerer", buffer);
 }
 
-static void closedCallback(void *ptr) {
+static void RTC_API closedCallback(int id, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->connected = false;
 }
 
-static void messageCallback(const char *message, int size, void *ptr) {
-        // Peer *peer = (Peer *)ptr;
+static void RTC_API messageCallback(int id, const char *message, int size, void *ptr) {
 	if (size < 0) { // negative size indicates a null-terminated string
 		printf("Message %s: %s\n", "offerer", message);
 	} else {

examples/copy-paste/answerer.cpp

@@ -36,12 +36,12 @@ int main(int argc, char **argv) {
 
 	auto pc = std::make_shared<PeerConnection>(config);
 
-	pc->onLocalDescription([](const Description &description) {
+	pc->onLocalDescription([](Description description) {
 		cout << "Local Description (Paste this to the other peer):" << endl;
 		cout << string(description) << endl;
 	});
 
-	pc->onLocalCandidate([](const Candidate &candidate) {
+	pc->onLocalCandidate([](Candidate candidate) {
 		cout << "Local Candidate (Paste this to the other peer after the local description):"
 		     << endl;
 		cout << string(candidate) << endl << endl;
@@ -60,7 +60,7 @@ int main(int argc, char **argv) {
 
 		dc->onClosed([&]() { cout << "[DataChannel closed: " << dc->label() << "]" << endl; });
 
-		dc->onMessage([](const variant<binary, string> &message) {
+		dc->onMessage([](variant<binary, string> message) {
 			if (holds_alternative<string>(message)) {
 				cout << "[Received message: " << get<string>(message) << "]" << endl;
 			}
@@ -127,13 +127,11 @@ int main(int argc, char **argv) {
 				cout << "** Channel is not Open ** ";
 				break;
 			}
-			CandidateInfo local, remote;
+			Candidate local, remote;
 			std::optional<std::chrono::milliseconds> rtt = pc->rtt();
 			if (pc->getSelectedCandidatePair(&local, &remote)) {
-				cout << "Local: " << local.address << ":" << local.port << " " << local.type << " "
-				     << local.transportType << endl;
-				cout << "Remote: " << remote.address << ":" << remote.port << " " << remote.type
-				     << " " << remote.transportType << endl;
+				cout << "Local: " << local << endl;
+				cout << "Remote: " << remote << endl;
 				cout << "Bytes Sent:" << pc->bytesSent()
 				     << " / Bytes Received:" << pc->bytesReceived() << " / Round-Trip Time:";
 				if (rtt.has_value())

examples/copy-paste/offerer.cpp

@@ -36,12 +36,12 @@ int main(int argc, char **argv) {
 
 	auto pc = std::make_shared<PeerConnection>(config);
 
-	pc->onLocalDescription([](const Description &description) {
+	pc->onLocalDescription([](Description description) {
 		cout << "Local Description (Paste this to the other peer):" << endl;
 		cout << string(description) << endl;
 	});
 
-	pc->onLocalCandidate([](const Candidate &candidate) {
+	pc->onLocalCandidate([](Candidate candidate) {
 		cout << "Local Candidate (Paste this to the other peer after the local description):"
 		     << endl;
 		cout << string(candidate) << endl << endl;
@@ -60,7 +60,7 @@ int main(int argc, char **argv) {
 
 	dc->onClosed([&]() { cout << "[DataChannel closed: " << dc->label() << "]" << endl; });
 
-	dc->onMessage([](const variant<binary, string> &message) {
+	dc->onMessage([](variant<binary, string> message) {
 		if (holds_alternative<string>(message)) {
 			cout << "[Received: " << get<string>(message) << "]" << endl;
 		}
@@ -127,13 +127,11 @@ int main(int argc, char **argv) {
 				cout << "** Channel is not Open ** ";
 				break;
 			}
-			CandidateInfo local, remote;
+			Candidate local, remote;
 			std::optional<std::chrono::milliseconds> rtt = pc->rtt();
 			if (pc->getSelectedCandidatePair(&local, &remote)) {
-				cout << "Local: " << local.address << ":" << local.port << " " << local.type << " "
-				     << local.transportType << endl;
-				cout << "Remote: " << remote.address << ":" << remote.port << " " << remote.type
-				     << " " << remote.transportType << endl;
+				cout << "Local: " << local << endl;
+				cout << "Remote: " << remote << endl;
 				cout << "Bytes Sent:" << pc->bytesSent()
 				     << " / Bytes Received:" << pc->bytesReceived() << " / Round-Trip Time:";
 				if (rtt.has_value())

examples/media/CMakeLists.txt

@@ -0,0 +1,14 @@
+cmake_minimum_required(VERSION 3.7)
+
+add_executable(datachannel-media main.cpp)
+set_target_properties(datachannel-media PROPERTIES
+        CXX_STANDARD 17
+        OUTPUT_NAME media)
+
+if(WIN32)
+    target_link_libraries(datachannel-media datachannel-static) # DLL exports only the C API
+else()
+    target_link_libraries(datachannel-media datachannel)
+endif()
+
+target_link_libraries(datachannel-media datachannel nlohmann_json)

examples/media/README.md

@@ -0,0 +1,19 @@
+# Example Webcam from Browser to Port 5000
+This is an example copy/paste demo to send your webcam from your browser and out port 5000 through the demo application.
+
+## How to use
+Open main.html in your browser (you must open it either as HTTPS or as a domain of http://localhost).
+
+Start the application and copy it's offer into the text box of the web page.
+
+Copy the answer of the webpage back into the application.
+
+You will now see RTP traffic on `localhost:5000` of the computer that the application is running on.
+
+Use the following gstreamer demo pipeline to display the traffic
+(you might need to wave your hand in front of your camera to force an I-frame).
+
+```
+$ gst-launch-1.0 udpsrc address=127.0.0.1 port=5000 caps="application/x-rtp" ! queue ! rtph264depay ! video/x-h264,stream-format=byte-stream ! queue ! avdec_h264 ! queue ! autovideosink
+```
+

examples/media/main.cpp

@@ -0,0 +1,97 @@
+/*
+ * libdatachannel client example
+ * Copyright (c) 2020 Staz Modrzynski
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define _WINSOCK_DEPRECATED_NO_WARNINGS
+
+#include "rtc/rtc.hpp"
+
+#include <iostream>
+#include <memory>
+#include <utility>
+
+#include <nlohmann/json.hpp>
+
+#ifdef _WIN32
+#include <winsock2.h>
+#else
+#include <arpa/inet.h>
+typedef int SOCKET;
+#endif
+
+using nlohmann::json;
+
+int main() {
+	try {
+		rtc::InitLogger(rtc::LogLevel::Debug);
+		auto pc = std::make_shared<rtc::PeerConnection>();
+
+		pc->onStateChange(
+		    [](rtc::PeerConnection::State state) { std::cout << "State: " << state << std::endl; });
+
+		pc->onGatheringStateChange([pc](rtc::PeerConnection::GatheringState state) {
+			std::cout << "Gathering State: " << state << std::endl;
+			if (state == rtc::PeerConnection::GatheringState::Complete) {
+				auto description = pc->localDescription();
+				json message = {{"type", description->typeString()},
+				                {"sdp", std::string(description.value())}};
+				std::cout << message << std::endl;
+			}
+		});
+
+		SOCKET sock = socket(AF_INET, SOCK_DGRAM, 0);
+		sockaddr_in addr;
+		addr.sin_addr.s_addr = inet_addr("127.0.0.1");
+		addr.sin_port = htons(5000);
+		addr.sin_family = AF_INET;
+
+		rtc::Description::Video media("video", rtc::Description::Direction::RecvOnly);
+		media.addH264Codec(96);
+		media.setBitrate(
+		    3000); // Request 3Mbps (Browsers do not encode more than 2.5MBps from a webcam)
+
+		auto track = pc->addTrack(media);
+
+		auto session = std::make_shared<rtc::RtcpReceivingSession>();
+		track->setRtcpHandler(session);
+
+		track->onMessage(
+		    [session, sock, addr](rtc::binary message) {
+			    // This is an RTP packet
+			    sendto(sock, reinterpret_cast<const char *>(message.data()), int(message.size()), 0,
+			           reinterpret_cast<const struct sockaddr *>(&addr), sizeof(addr));
+		    },
+		    nullptr);
+
+		pc->setLocalDescription();
+
+		std::cout << "Expect RTP video traffic on localhost:5000" << std::endl;
+		std::cout << "Please copy/paste the answer provided by the browser: " << std::endl;
+		std::string sdp;
+		std::getline(std::cin, sdp);
+		std::cout << "Got answer" << sdp << std::endl;
+		json j = json::parse(sdp);
+		rtc::Description answer(j["sdp"].get<std::string>(), j["type"].get<std::string>());
+		pc->setRemoteDescription(answer);
+		std::cout << "Press any key to exit." << std::endl;
+		std::cin >> sdp;
+
+	} catch (const std::exception &e) {
+		std::cerr << "Error: " << e.what() << std::endl;
+	}
+}

examples/media/main.html

@@ -0,0 +1,45 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>libdatachannel media example</title>
+</head>
+<body>
+
+<p>Please enter the offer provided to you by the application: </p>
+<textarea cols="50" rows="50"></textarea>
+<button>Submit</button>
+
+<script>
+    document.querySelector('button').addEventListener('click',  async () => {
+        let offer = JSON.parse(document.querySelector('textarea').value);
+        rtc = new RTCPeerConnection({
+            // Recommended for libdatachannel
+            bundlePolicy: "max-bundle",
+        });
+
+        rtc.onicegatheringstatechange = (state) => {
+            if (rtc.iceGatheringState === 'complete') {
+                // We only want to provide an answer once all of our candidates have been added to the SDP.
+                let answer = rtc.localDescription;
+                document.querySelector('textarea').value = JSON.stringify({"type": answer.type, sdp: answer.sdp});
+                document.querySelector('p').value = 'Please paste the answer in the application.';
+                alert('Please paste the answer in the application.');
+            }
+        }
+        await rtc.setRemoteDescription(offer);
+
+        let media = await navigator.mediaDevices.getUserMedia({
+            video: {
+                width: 1280,
+                height: 720
+            }
+        });
+        media.getTracks().forEach(track => rtc.addTrack(track, media));
+        let answer = await rtc.createAnswer();
+        await rtc.setLocalDescription(answer);
+    })
+</script>
+
+</body>
+</html>

examples/sfu-media/CMakeLists.txt

@@ -0,0 +1,15 @@
+cmake_minimum_required(VERSION 3.7)
+
+add_executable(datachannel-sfu-media main.cpp)
+set_target_properties(datachannel-sfu-media PROPERTIES
+		CXX_STANDARD 17
+		OUTPUT_NAME sfu-media)
+
+if(WIN32)
+	target_link_libraries(datachannel-sfu-media datachannel-static) # DLL exports only the C API
+else()
+	target_link_libraries(datachannel-sfu-media datachannel)
+endif()
+
+target_link_libraries(datachannel-sfu-media datachannel nlohmann_json)
+

examples/sfu-media/main.cpp

@@ -0,0 +1,134 @@
+/*
+ * libdatachannel client example
+ * Copyright (c) 2020 Staz Modrzynski
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define _WINSOCK_DEPRECATED_NO_WARNINGS
+
+#include "rtc/rtc.hpp"
+
+#include <iostream>
+#include <memory>
+
+#include <nlohmann/json.hpp>
+
+using nlohmann::json;
+
+struct Receiver {
+	std::shared_ptr<rtc::PeerConnection> conn;
+	std::shared_ptr<rtc::Track> track;
+};
+int main() {
+	std::vector<std::shared_ptr<Receiver>> receivers;
+
+	try {
+		rtc::InitLogger(rtc::LogLevel::Info);
+
+		auto pc = std::make_shared<rtc::PeerConnection>();
+		pc->onStateChange(
+		    [](rtc::PeerConnection::State state) { std::cout << "State: " << state << std::endl; });
+		pc->onGatheringStateChange([pc](rtc::PeerConnection::GatheringState state) {
+			std::cout << "Gathering State: " << state << std::endl;
+			if (state == rtc::PeerConnection::GatheringState::Complete) {
+				auto description = pc->localDescription();
+				json message = {{"type", description->typeString()},
+				                {"sdp", std::string(description.value())}};
+				std::cout << "Please copy/paste this offer to the SENDER: " << message << std::endl;
+			}
+		});
+
+		rtc::Description::Video media("video", rtc::Description::Direction::RecvOnly);
+		media.addH264Codec(96);
+		media.setBitrate(
+		    3000); // Request 3Mbps (Browsers do not encode more than 2.5MBps from a webcam)
+
+		auto track = pc->addTrack(media);
+		pc->setLocalDescription();
+
+		auto session = std::make_shared<rtc::RtcpReceivingSession>();
+		track->setRtcpHandler(session);
+
+		const rtc::SSRC targetSSRC = 4;
+
+		track->onMessage(
+		    [&receivers, targetSSRC](rtc::binary message) {
+			    // This is an RTP packet
+			    auto rtp = (rtc::RTP *)message.data();
+			    rtp->setSsrc(targetSSRC);
+			    for (auto pc : receivers) {
+				    if (pc->track != nullptr && pc->track->isOpen()) {
+					    pc->track->send(message);
+				    }
+			    }
+		    },
+		    nullptr);
+
+		// Set the SENDERS Answer
+		{
+			std::cout << "Please copy/paste the answer provided by the SENDER: " << std::endl;
+			std::string sdp;
+			std::getline(std::cin, sdp);
+			std::cout << "Got answer" << sdp << std::endl;
+			json j = json::parse(sdp);
+			rtc::Description answer(j["sdp"].get<std::string>(), j["type"].get<std::string>());
+			pc->setRemoteDescription(answer);
+		}
+
+		// For each receiver
+		while (true) {
+			auto pc = std::make_shared<Receiver>();
+			pc->conn = std::make_shared<rtc::PeerConnection>();
+			pc->conn->onStateChange([](rtc::PeerConnection::State state) {
+				std::cout << "State: " << state << std::endl;
+			});
+			pc->conn->onGatheringStateChange([pc](rtc::PeerConnection::GatheringState state) {
+				std::cout << "Gathering State: " << state << std::endl;
+				if (state == rtc::PeerConnection::GatheringState::Complete) {
+					auto description = pc->conn->localDescription();
+					json message = {{"type", description->typeString()},
+					                {"sdp", std::string(description.value())}};
+					std::cout << "Please copy/paste this offer to the RECEIVER: " << message
+					          << std::endl;
+				}
+			});
+			rtc::Description::Video media("video", rtc::Description::Direction::SendOnly);
+			media.addH264Codec(96);
+			media.setBitrate(
+			    3000); // Request 3Mbps (Browsers do not encode more than 2.5MBps from a webcam)
+
+			media.addSSRC(targetSSRC, "video-send");
+
+			pc->track = pc->conn->addTrack(media);
+			pc->conn->setLocalDescription();
+
+			pc->track->onMessage([](rtc::binary var) {}, nullptr);
+
+			std::cout << "Please copy/paste the answer provided by the RECEIVER: " << std::endl;
+			std::string sdp;
+			std::getline(std::cin, sdp);
+			std::cout << "Got answer" << sdp << std::endl;
+			json j = json::parse(sdp);
+			rtc::Description answer(j["sdp"].get<std::string>(), j["type"].get<std::string>());
+			pc->conn->setRemoteDescription(answer);
+
+			receivers.push_back(pc);
+		}
+
+	} catch (const std::exception &e) {
+		std::cerr << "Error: " << e.what() << std::endl;
+	}
+}

examples/sfu-media/main.html

@@ -0,0 +1,87 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>libdatachannel media example</title>
+</head>
+<body>
+
+<div style="display:inline-block; width:40%;">
+    <h1>SENDER</h1>
+    <p id="send-help">Please enter the offer provided to you by the application: </p>
+    <textarea style="width:100%;" id=send-text rows="50"></textarea>
+    <button id=send-btn>Submit</button>
+</div>
+<div style="display:inline-block; width:40%;">
+    <h1>RECEIVER</h1>
+    <p id="recv-help">Please enter the offer provided to you by the application: </p>
+    <textarea id=recv-text style="width:100%;" rows="50"></textarea>
+    <button id=recv-btn>Submit</button>
+</div>
+<div id="videos">
+
+</div>
+<script>
+    document.querySelector('#send-btn').addEventListener('click',  async () => {
+        let offer = JSON.parse(document.querySelector('#send-text').value);
+        rtc = new RTCPeerConnection({
+            // Recommended for libdatachannel
+            bundlePolicy: "max-bundle",
+        });
+
+        rtc.onicegatheringstatechange = (state) => {
+            if (rtc.iceGatheringState === 'complete') {
+                // We only want to provide an answer once all of our candidates have been added to the SDP.
+                let answer = rtc.localDescription;
+                document.querySelector('#send-text').value = JSON.stringify({"type": answer.type, sdp: answer.sdp});
+                document.querySelector('#send-help').value = 'Please paste the answer in the application.';
+                alert('Please paste the answer in the application.');
+            }
+        }
+        await rtc.setRemoteDescription(offer);
+
+        let media = await navigator.mediaDevices.getUserMedia({
+            video: {
+                width: 1280,
+                height: 720
+            }
+        });
+        media.getTracks().forEach(track => rtc.addTrack(track, media));
+        let answer = await rtc.createAnswer();
+        await rtc.setLocalDescription(answer);
+    });
+
+    document.querySelector('#recv-btn').addEventListener('click',  async () => {
+        let offer = JSON.parse(document.querySelector('#recv-text').value);
+        rtc = new RTCPeerConnection({
+            // Recommended for libdatachannel
+            bundlePolicy: "max-bundle",
+        });
+
+        rtc.onicegatheringstatechange = (state) => {
+            if (rtc.iceGatheringState === 'complete') {
+                // We only want to provide an answer once all of our candidates have been added to the SDP.
+                let answer = rtc.localDescription;
+                document.querySelector('#recv-text').value = JSON.stringify({"type": answer.type, sdp: answer.sdp});
+                document.querySelector('#recv-help').value = 'Please paste the answer in the application.';
+                alert('Please paste the answer in the application.');
+            }
+        }
+        let trackCount = 0;
+        rtc.ontrack = (ev) => {
+            let thisID = trackCount++;
+
+            document.querySelector("#videos").innerHTML += "<video width=100% height=100% id='video-" + thisID + "'></video>";
+            let tracks = [];
+            rtc.getReceivers().forEach(recv => tracks.push(recv.track));
+            document.querySelector("#video-" + thisID).srcObject = new MediaStream(tracks);
+            document.querySelector("#video-" + thisID).play();
+        };
+        await rtc.setRemoteDescription(offer);
+        let answer = await rtc.createAnswer();
+        await rtc.setLocalDescription(answer);
+    });
+</script>
+
+</body>
+</html>

examples/signaling-server-python/signaling-server.py

@@ -63,16 +63,20 @@ async def handle_websocket(websocket, path):
             print('Client {} disconnected'.format(client_id))
 
 if __name__ == '__main__':
-    port = int(sys.argv[1]) if len(sys.argv) > 1 else 8000
+    # Usage: ./server.py [[host:]port] [SSL certificate file]
+    endpoint_or_port = sys.argv[1] if len(sys.argv) > 1 else "8000"
     ssl_cert = sys.argv[2] if len(sys.argv) > 2 else None
 
+    endpoint = endpoint_or_port if ':' in endpoint_or_port else "127.0.0.1:" + endpoint_or_port
+
     if ssl_cert:
         ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
         ssl_context.load_cert_chain(ssl_cert)
     else:
         ssl_context = None
 
-    print('Listening on port {}'.format(port))
-    start_server = websockets.serve(handle_websocket, '127.0.0.1', port, ssl=ssl_context)
+    print('Listening on {}'.format(endpoint))
+    host, port = endpoint.rsplit(':', 1)
+    start_server = websockets.serve(handle_websocket, host, int(port), ssl=ssl_context)
     asyncio.get_event_loop().run_until_complete(start_server)
     asyncio.get_event_loop().run_forever()

examples/signaling-server-rust/Cargo.lock

@@ -348,7 +348,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a9f8082297d534141b30c8d39e9b1773713ab50fdbe4ff30f750d063b3bfd701"
 
 [[package]]
-name = "libdatachannel_signaling_example"
+name = "libdatachannel_signaling_server_example"
 version = "0.1.0"
 dependencies = [
  "futures-channel",

examples/signaling-server-rust/src/main.rs

@@ -92,7 +92,9 @@ async fn handle(clients: ClientsMap, stream: TcpStream) {
 #[tokio::main]
 async fn main() -> Result<(), std::io::Error> {
     let service = env::args().nth(1).unwrap_or("8000".to_string());
-    let endpoint = format!("127.0.0.1:{}", service);
+    let endpoint = if service.contains(':') { service } else { format!("127.0.0.1:{}", service) };
+
+	println!("Listening on {}", endpoint);
 
     let mut listener = TcpListener::bind(endpoint)
     	.await.expect("Listener binding failed");

examples/web/package-lock.json

@@ -4,6 +4,14 @@
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
+    "bufferutil": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/bufferutil/-/bufferutil-4.0.1.tgz",
+      "integrity": "sha512-xowrxvpxojqkagPcWRQVXZl0YXhRhAtBEIq3VoER1NH5Mw1n1o0ojdspp+GS2J//2gCVyrzQDApQ4unGF+QOoA==",
+      "requires": {
+        "node-gyp-build": "~3.7.0"
+      }
+    },
     "d": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/d/-/d-1.0.1.tgz",
@@ -59,9 +67,9 @@
       },
       "dependencies": {
         "type": {
-          "version": "2.0.0",
-          "resolved": "https://registry.npmjs.org/type/-/type-2.0.0.tgz",
-          "integrity": "sha512-KBt58xCHry4Cejnc2ISQAF7QY+ORngsWfxezO68+12hKV6lQY8P/psIkcbjeHWn7MqcgciWJyCCevFMJdIXpow=="
+          "version": "2.1.0",
+          "resolved": "https://registry.npmjs.org/type/-/type-2.1.0.tgz",
+          "integrity": "sha512-G9absDWvhAWCV2gmF1zKud3OyC61nZDwWvBL2DApaVFogI07CprggiQAOOjvp2NRjYWFzPyu7vwtDrQFq8jeSA=="
         }
       }
     },
@@ -75,16 +83,16 @@
       "resolved": "https://registry.npmjs.org/ms/-/ms-2.0.0.tgz",
       "integrity": "sha1-VgiurfwAvmwpAd9fmGF4jeDVl8g="
     },
-    "nan": {
-      "version": "2.14.1",
-      "resolved": "https://registry.npmjs.org/nan/-/nan-2.14.1.tgz",
-      "integrity": "sha512-isWHgVjnFjh2x2yuJ/tj3JbwoHu3UC2dX5G/88Cm24yB6YopVgxvBObDY7n5xW6ExmFhJpSEQqFPvq9zaXc8Jw=="
-    },
     "next-tick": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/next-tick/-/next-tick-1.0.0.tgz",
       "integrity": "sha1-yobR/ogoFpsBICCOPchCS524NCw="
     },
+    "node-gyp-build": {
+      "version": "3.7.0",
+      "resolved": "https://registry.npmjs.org/node-gyp-build/-/node-gyp-build-3.7.0.tgz",
+      "integrity": "sha512-L/Eg02Epx6Si2NXmedx+Okg+4UHqmaf3TNcxd50SF9NQGcJaON3AtU++kax69XV7YWz4tUspqZSAsVofhFKG2w=="
+    },
     "type": {
       "version": "1.2.0",
       "resolved": "https://registry.npmjs.org/type/-/type-1.2.0.tgz",
@@ -98,15 +106,24 @@
         "is-typedarray": "^1.0.0"
       }
     },
-    "websocket": {
-      "version": "1.0.31",
-      "resolved": "https://registry.npmjs.org/websocket/-/websocket-1.0.31.tgz",
-      "integrity": "sha512-VAouplvGKPiKFDTeCCO65vYHsyay8DqoBSlzIO3fayrfOgU94lQN5a1uWVnFrMLceTJw/+fQXR5PGbUVRaHshQ==",
+    "utf-8-validate": {
+      "version": "5.0.2",
+      "resolved": "https://registry.npmjs.org/utf-8-validate/-/utf-8-validate-5.0.2.tgz",
+      "integrity": "sha512-SwV++i2gTD5qh2XqaPzBnNX88N6HdyhQrNNRykvcS0QKvItV9u3vPEJr+X5Hhfb1JC0r0e1alL0iB09rY8+nmw==",
       "requires": {
+        "node-gyp-build": "~3.7.0"
+      }
+    },
+    "websocket": {
+      "version": "1.0.32",
+      "resolved": "https://registry.npmjs.org/websocket/-/websocket-1.0.32.tgz",
+      "integrity": "sha512-i4yhcllSP4wrpoPMU2N0TQ/q0O94LRG/eUQjEAamRltjQ1oT1PFFKOG4i877OlJgCG8rw6LrrowJp+TYCEWF7Q==",
+      "requires": {
+        "bufferutil": "^4.0.1",
         "debug": "^2.2.0",
         "es5-ext": "^0.10.50",
-        "nan": "^2.14.0",
         "typedarray-to-buffer": "^3.1.5",
+        "utf-8-validate": "^5.0.2",
         "yaeti": "^0.0.6"
       }
     },

examples/web/package.json

@@ -18,6 +18,6 @@
   },
   "homepage": "https://github.com/paullouisageneau/libdatachannel#readme",
   "dependencies": {
-    "websocket": "^1.0.31"
+    "websocket": "^1.0.32"
   }
 }

examples/web/script.js

@@ -55,7 +55,7 @@ function openSignaling(url) {
     const ws = new WebSocket(url);
     ws.onopen = () => resolve(ws);
     ws.onerror = () => reject(new Error('WebSocket error'));
-    ws.onclosed = () => console.error('WebSocket disconnected');
+    ws.onclose = () => console.error('WebSocket disconnected');
     ws.onmessage = (e) => {
       if(typeof(e.data) != 'string') return;
       const message = JSON.parse(e.data);

examples/web/server.js

@@ -98,5 +98,12 @@ wsServer.on('request', (req) => {
   clients[id] = conn;
 });
 
-httpServer.listen(8000);
+const endpoint = process.env.PORT || '8000';
+const splitted = endpoint.split(':');
+const port = splitted.pop();
+const hostname = splitted.join(':') || '127.0.0.1';
+
+httpServer.listen(port, hostname, () => {
+  console.log(`Server listening on ${hostname}:${port}`);
+});
 

include/rtc/candidate.hpp

@@ -25,38 +25,59 @@
 
 namespace rtc {
 
-enum class CandidateType { Host = 0, ServerReflexive, PeerReflexive, Relayed };
-enum class CandidateTransportType { Udp = 0, TcpActive, TcpPassive, TcpSo };
-struct CandidateInfo {
-	string address;
-	int port;
-	CandidateType type;
-	CandidateTransportType transportType;
-};
-
 class Candidate {
 public:
-	Candidate(string candidate, string mid = "");
+	enum class Family { Unresolved, Ipv4, Ipv6 };
+	enum class Type { Unknown, Host, ServerReflexive, PeerReflexive, Relayed };
+	enum class TransportType { Unknown, Udp, TcpActive, TcpPassive, TcpSo, TcpUnknown };
+
+	Candidate();
+	Candidate(string candidate);
+	Candidate(string candidate, string mid);
+
+	void hintMid(string mid);
 
 	enum class ResolveMode { Simple, Lookup };
 	bool resolve(ResolveMode mode = ResolveMode::Simple);
-	bool isResolved() const;
 
+	Type type() const;
+	TransportType transportType() const;
+	uint32_t priority() const;
 	string candidate() const;
 	string mid() const;
 	operator string() const;
 
+	bool operator==(const Candidate &other) const;
+	bool operator!=(const Candidate &other) const;
+
+	bool isResolved() const;
+	Family family() const;
+	std::optional<string> address() const;
+	std::optional<uint16_t> port() const;
+
 private:
-	string mCandidate;
-	string mMid;
-	bool mIsResolved;
+	void parse(string candidate);
+
+	string mFoundation;
+	uint32_t mComponent, mPriority;
+	string mTypeString, mTransportString;
+	Type mType;
+	TransportType mTransportType;
+	string mNode, mService;
+	string mTail;
+
+	std::optional<string> mMid;
+
+	// Extracted on resolution
+	Family mFamily;
+	string mAddress;
+	uint16_t mPort;
 };
 
 } // namespace rtc
 
 std::ostream &operator<<(std::ostream &out, const rtc::Candidate &candidate);
-std::ostream &operator<<(std::ostream &out, const rtc::CandidateType &type);
-std::ostream &operator<<(std::ostream &out, const rtc::CandidateTransportType &transportType);
+std::ostream &operator<<(std::ostream &out, const rtc::Candidate::Type &type);
+std::ostream &operator<<(std::ostream &out, const rtc::Candidate::TransportType &transportType);
 
 #endif
-

include/rtc/channel.hpp

@@ -20,6 +20,7 @@
 #define RTC_CHANNEL_H
 
 #include "include.hpp"
+#include "message.hpp"
 
 #include <atomic>
 #include <functional>
@@ -33,7 +34,7 @@ public:
 	virtual ~Channel() = default;
 
 	virtual void close() = 0;
-	virtual bool send(const std::variant<binary, string> &data) = 0; // returns false if buffered
+	virtual bool send(message_variant data) = 0; // returns false if buffered
 
 	virtual bool isOpen() const = 0;
 	virtual bool isClosed() const = 0;
@@ -42,24 +43,25 @@ public:
 
 	void onOpen(std::function<void()> callback);
 	void onClosed(std::function<void()> callback);
-	void onError(std::function<void(const string &error)> callback);
+	void onError(std::function<void(string error)> callback);
 
-	void onMessage(std::function<void(const std::variant<binary, string> &data)> callback);
-	void onMessage(std::function<void(const binary &data)> binaryCallback,
-	               std::function<void(const string &data)> stringCallback);
+	void onMessage(std::function<void(message_variant data)> callback);
+	void onMessage(std::function<void(binary data)> binaryCallback,
+	               std::function<void(string data)> stringCallback);
 
 	void onBufferedAmountLow(std::function<void()> callback);
 	void setBufferedAmountLowThreshold(size_t amount);
 
 	// Extended API
-	virtual std::optional<std::variant<binary, string>> receive() = 0; // only if onMessage unset
+	virtual std::optional<message_variant> receive() = 0; // only if onMessage unset
+	virtual std::optional<message_variant> peek() = 0;    // only if onMessage unset
 	virtual size_t availableAmount() const;               // total size available to receive
 	void onAvailable(std::function<void()> callback);
 
 protected:
 	virtual void triggerOpen();
 	virtual void triggerClosed();
-	virtual void triggerError(const string &error);
+	virtual void triggerError(string error);
 	virtual void triggerAvailable(size_t count);
 	virtual void triggerBufferedAmount(size_t amount);
 
@@ -68,8 +70,8 @@ protected:
 private:
 	synchronized_callback<> mOpenCallback;
 	synchronized_callback<> mClosedCallback;
-	synchronized_callback<const string &> mErrorCallback;
-	synchronized_callback<const std::variant<binary, string> &> mMessageCallback;
+	synchronized_callback<string> mErrorCallback;
+	synchronized_callback<message_variant> mMessageCallback;
 	synchronized_callback<> mAvailableCallback;
 	synchronized_callback<> mBufferedAmountLowCallback;
 
@@ -80,4 +82,3 @@ private:
 } // namespace rtc
 
 #endif // RTC_CHANNEL_H
-

include/rtc/datachannel.hpp

@@ -36,21 +36,20 @@ namespace rtc {
 class SctpTransport;
 class PeerConnection;
 
-class DataChannel final : public std::enable_shared_from_this<DataChannel>, public Channel {
+class DataChannel : public std::enable_shared_from_this<DataChannel>, public Channel {
 public:
-	DataChannel(std::weak_ptr<PeerConnection> pc, unsigned int stream, string label,
-	            string protocol, Reliability reliability);
-	DataChannel(std::weak_ptr<PeerConnection> pc, std::weak_ptr<SctpTransport> transport,
-	            unsigned int stream);
-	~DataChannel();
+	DataChannel(std::weak_ptr<PeerConnection> pc, uint16_t stream, string label, string protocol,
+	            Reliability reliability);
+	virtual ~DataChannel();
 
-	unsigned int stream() const;
+	uint16_t stream() const;
+	uint16_t id() const;
 	string label() const;
 	string protocol() const;
 	Reliability reliability() const;
 
 	void close(void) override;
-	bool send(const std::variant<binary, string> &data) override;
+	bool send(message_variant data) override;
 	bool send(const byte *data, size_t size);
 	template <typename Buffer> bool sendBuffer(const Buffer &buf);
 	template <typename Iterator> bool sendBuffer(Iterator first, Iterator last);
@@ -61,19 +60,20 @@ public:
 
 	// Extended API
 	size_t availableAmount() const override;
-	std::optional<std::variant<binary, string>> receive() override;
+	std::optional<message_variant> receive() override;
+	std::optional<message_variant> peek() override;
 
-private:
+protected:
+	virtual void open(std::shared_ptr<SctpTransport> transport);
+	virtual void processOpenMessage(message_ptr message);
 	void remoteClose();
-	void open(std::shared_ptr<SctpTransport> transport);
 	bool outgoing(message_ptr message);
 	void incoming(message_ptr message);
-	void processOpenMessage(message_ptr message);
 
 	const std::weak_ptr<PeerConnection> mPeerConnection;
 	std::weak_ptr<SctpTransport> mSctpTransport;
 
-	unsigned int mStream;
+	uint16_t mStream;
 	string mLabel;
 	string mProtocol;
 	std::shared_ptr<Reliability> mReliability;
@@ -81,11 +81,27 @@ private:
 	std::atomic<bool> mIsOpen = false;
 	std::atomic<bool> mIsClosed = false;
 
+private:
 	Queue<message_ptr> mRecvQueue;
 
 	friend class PeerConnection;
 };
 
+class NegociatedDataChannel final : public DataChannel {
+public:
+	NegociatedDataChannel(std::weak_ptr<PeerConnection> pc, uint16_t stream, string label,
+	                      string protocol, Reliability reliability);
+	NegociatedDataChannel(std::weak_ptr<PeerConnection> pc, std::weak_ptr<SctpTransport> transport,
+	                      uint16_t stream);
+	~NegociatedDataChannel();
+
+private:
+	void open(std::shared_ptr<SctpTransport> transport) override;
+	void processOpenMessage(message_ptr message) override;
+
+	friend class PeerConnection;
+};
+
 template <typename Buffer> std::pair<const byte *, size_t> to_bytes(const Buffer &buf) {
 	using T = typename std::remove_pointer<decltype(buf.data())>::type;
 	using E = typename std::conditional<std::is_void<T>::value, byte, T>::type;

include/rtc/description.hpp

@@ -1,5 +1,6 @@
 /**
- * Copyright (c) 2019 Paul-Louis Ageneau
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
+ * Copyright (c) 2020 Staz Modrzynski
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -24,82 +25,228 @@
 
 #include <iostream>
 #include <map>
+#include <memory>
 #include <optional>
+#include <variant>
 #include <vector>
 
 namespace rtc {
 
 class Description {
 public:
-	enum class Type { Unspec = 0, Offer = 1, Answer = 2 };
-	enum class Role { ActPass = 0, Passive = 1, Active = 2 };
+	enum class Type { Unspec, Offer, Answer, Pranswer, Rollback };
+	enum class Role { ActPass, Passive, Active };
+	enum class Direction { SendOnly, RecvOnly, SendRecv, Inactive, Unknown };
 
-	Description(const string &sdp, const string &typeString = "");
-	Description(const string &sdp, Type type);
-	Description(const string &sdp, Type type, Role role);
+	Description(const string &sdp, Type type = Type::Unspec, Role role = Role::ActPass);
+	Description(const string &sdp, string typeString);
 
 	Type type() const;
 	string typeString() const;
 	Role role() const;
-	string roleString() const;
-	string dataMid() const;
+	string bundleMid() const;
+	std::optional<string> iceUfrag() const;
+	std::optional<string> icePwd() const;
 	std::optional<string> fingerprint() const;
-	std::optional<uint16_t> sctpPort() const;
-	std::optional<size_t> maxMessageSize() const;
 	bool ended() const;
 
 	void hintType(Type type);
-	void setDataMid(string mid);
 	void setFingerprint(string fingerprint);
-	void setSctpPort(uint16_t port);
-	void setMaxMessageSize(size_t size);
 
+	bool hasCandidate(const Candidate &candidate) const;
 	void addCandidate(Candidate candidate);
+	void addCandidates(std::vector<Candidate> candidates);
 	void endCandidates();
 	std::vector<Candidate> extractCandidates();
 
-	bool hasMedia() const;
-	void addMedia(const Description &source);
+	operator string() const;
+	string generateSdp(string_view eol) const;
+	string generateApplicationSdp(string_view eol) const;
+
+	class Entry {
+	public:
+		virtual ~Entry() = default;
+
+		virtual string type() const { return mType; }
+		virtual string description() const { return mDescription; }
+		virtual string mid() const { return mMid; }
+		Direction direction() const { return mDirection; }
+		void setDirection(Direction dir);
 
 		operator string() const;
-	string generateSdp(const string &eol) const;
+		string generateSdp(string_view eol, string_view addr, string_view port) const;
 
-private:
-	Type mType;
-	Role mRole;
-	string mSessionId;
-	string mIceUfrag, mIcePwd;
-	std::optional<string> mFingerprint;
+		virtual void parseSdpLine(string_view line);
 
-	// Data
-	struct Data {
-		string mid;
-		std::optional<uint16_t> sctpPort;
-		std::optional<size_t> maxMessageSize;
+		std::vector<string>::iterator beginAttributes();
+		std::vector<string>::iterator endAttributes();
+		std::vector<string>::iterator removeAttribute(std::vector<string>::iterator iterator);
+
+	protected:
+		Entry(const string &mline, string mid, Direction dir = Direction::Unknown);
+		virtual string generateSdpLines(string_view eol) const;
+
+		std::vector<string> mAttributes;
+
+	private:
+		string mType;
+		string mDescription;
+		string mMid;
+		Direction mDirection;
+	};
+
+	struct Application : public Entry {
+	public:
+		Application(string mid = "data");
+		virtual ~Application() = default;
+
+		string description() const override;
+		Application reciprocate() const;
+
+		void setSctpPort(uint16_t port) { mSctpPort = port; }
+		void hintSctpPort(uint16_t port) { mSctpPort = mSctpPort.value_or(port); }
+		void setMaxMessageSize(size_t size) { mMaxMessageSize = size; }
+
+		std::optional<uint16_t> sctpPort() const { return mSctpPort; }
+		std::optional<size_t> maxMessageSize() const { return mMaxMessageSize; }
+
+		virtual void parseSdpLine(string_view line) override;
+
+	private:
+		virtual string generateSdpLines(string_view eol) const override;
+
+		std::optional<uint16_t> mSctpPort;
+		std::optional<size_t> mMaxMessageSize;
 	};
-	Data mData;
 
 	// Media (non-data)
-	struct Media {
-		Media(const string &mline);
-		string type;
-		string description;
-		string mid;
-		std::vector<string> attributes;
+	class Media : public Entry {
+	public:
+		Media(const string &sdp);
+		Media(const string &mline, string mid, Direction dir = Direction::SendOnly);
+		virtual ~Media() = default;
+
+		string description() const override;
+		Media reciprocate() const;
+
+		void removeFormat(const string &fmt);
+
+		void addSSRC(uint32_t ssrc, std::string name);
+		void addSSRC(uint32_t ssrc);
+		void replaceSSRC(uint32_t oldSSRC, uint32_t ssrc, string name);
+		bool hasSSRC(uint32_t ssrc);
+		std::vector<uint32_t> getSSRCs();
+
+		void setBitrate(int bitrate);
+		int getBitrate() const;
+
+		bool hasPayloadType(int payloadType) const;
+
+		virtual void parseSdpLine(string_view line) override;
+
+		struct RTPMap {
+			RTPMap(string_view mline);
+			RTPMap() {}
+
+			void removeFB(const string &string);
+			void addFB(const string &string);
+			void addAttribute(std::string attr) { fmtps.emplace_back(attr); }
+
+			int pt;
+			string format;
+			int clockRate;
+			string encParams;
+
+			std::vector<string> rtcpFbs;
+			std::vector<string> fmtps;
+
+			static int parsePT(string_view view);
+			void setMLine(string_view view);
 		};
-	std::map<int, Media> mMedia; // by m-line index
+
+		std::map<int, RTPMap>::iterator beginMaps();
+		std::map<int, RTPMap>::iterator endMaps();
+		std::map<int, RTPMap>::iterator removeMap(std::map<int, RTPMap>::iterator iterator);
+
+	private:
+		virtual string generateSdpLines(string_view eol) const override;
+
+		int mBas = -1;
+
+		Media::RTPMap &getFormat(int fmt);
+		Media::RTPMap &getFormat(const string &fmt);
+
+		std::map<int, RTPMap> mRtpMap;
+		std::vector<uint32_t> mSsrcs;
+
+	public:
+		void addRTPMap(const RTPMap &map);
+	};
+
+	class Audio : public Media {
+	public:
+		Audio(string mid = "audio", Direction dir = Direction::SendOnly);
+
+		void addAudioCodec(int payloadType, const string &codec);
+		void addOpusCodec(int payloadType);
+	};
+
+	class Video : public Media {
+	public:
+		Video(string mid = "video", Direction dir = Direction::SendOnly);
+
+		void addVideoCodec(int payloadType, const string &codec);
+		void addH264Codec(int payloadType);
+		void addVP8Codec(int payloadType);
+		void addVP9Codec(int payloadType);
+	};
+
+	bool hasApplication() const;
+	bool hasAudioOrVideo() const;
+	bool hasMid(string_view mid) const;
+
+	int addMedia(Media media);
+	int addMedia(Application application);
+	int addApplication(string mid = "data");
+	int addVideo(string mid = "video", Direction dir = Direction::SendOnly);
+	int addAudio(string mid = "audio", Direction dir = Direction::SendOnly);
+
+	std::variant<Media *, Application *> media(unsigned int index);
+	std::variant<const Media *, const Application *> media(unsigned int index) const;
+	unsigned int mediaCount() const;
+
+	Application *application();
+
+	static Type stringToType(const string &typeString);
+	static string typeToString(Type type);
+
+private:
+	std::optional<Candidate> defaultCandidate() const;
+	std::shared_ptr<Entry> createEntry(string mline, string mid, Direction dir);
+	void removeApplication();
+
+	Type mType;
+
+	// Session-level attributes
+	Role mRole;
+	string mUsername;
+	string mSessionId;
+	std::optional<string> mIceUfrag, mIcePwd;
+	std::optional<string> mFingerprint;
+
+	// Entries
+	std::vector<std::shared_ptr<Entry>> mEntries;
+	std::shared_ptr<Application> mApplication;
 
 	// Candidates
 	std::vector<Candidate> mCandidates;
 	bool mEnded = false;
-
-	static Type stringToType(const string &typeString);
-	static string typeToString(Type type);
-	static string roleToString(Role role);
 };
 
 } // namespace rtc
 
 std::ostream &operator<<(std::ostream &out, const rtc::Description &description);
+std::ostream &operator<<(std::ostream &out, rtc::Description::Type type);
+std::ostream &operator<<(std::ostream &out, rtc::Description::Role role);
 
 #endif

include/rtc/include.hpp

@@ -29,7 +29,7 @@
 
 #ifdef _WIN32
 #ifndef _WIN32_WINNT
-#define _WIN32_WINNT 0x0602
+#define _WIN32_WINNT 0x0602 // Windows 8
 #endif
 #endif
 
@@ -41,12 +41,14 @@
 #include <mutex>
 #include <optional>
 #include <string>
+#include <string_view>
 #include <vector>
 
 namespace rtc {
 
 using std::byte;
 using std::string;
+using std::string_view;
 using binary = std::vector<byte>;
 
 using std::nullopt;
@@ -64,11 +66,13 @@ const uint16_t DEFAULT_SCTP_PORT = 5000; // SCTP port to use by default
 const size_t DEFAULT_MAX_MESSAGE_SIZE = 65536;    // Remote max message size if not specified in SDP
 const size_t LOCAL_MAX_MESSAGE_SIZE = 256 * 1024; // Local max message size
 
+const size_t RECV_QUEUE_LIMIT = 1024 * 1024; // Max per-channel queue size
+
 const int THREADPOOL_SIZE = 4; // Number of threads in the global thread pool
 
 // overloaded helper
 template <class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
-template <class... Ts> overloaded(Ts...)->overloaded<Ts...>;
+template <class... Ts> overloaded(Ts...) -> overloaded<Ts...>;
 
 // weak_ptr bind helper
 template <typename F, typename T, typename... Args> auto weak_bind(F &&f, T *t, Args &&... _args) {
@@ -81,12 +85,29 @@ template <typename F, typename T, typename... Args> auto weak_bind(F &&f, T *t,
 	};
 }
 
-template <typename... P> class synchronized_callback {
+// scope_guard helper
+class scope_guard {
+public:
+	scope_guard(std::function<void()> func) : function(std::move(func)) {}
+	scope_guard(scope_guard &&other) = delete;
+	scope_guard(const scope_guard &) = delete;
+	void operator=(const scope_guard &) = delete;
+
+	~scope_guard() {
+		if (function)
+			function();
+	}
+
+private:
+	std::function<void()> function;
+};
+
+template <typename... Args> class synchronized_callback {
 public:
 	synchronized_callback() = default;
 	synchronized_callback(synchronized_callback &&cb) { *this = std::move(cb); }
 	synchronized_callback(const synchronized_callback &cb) { *this = cb; }
-	synchronized_callback(std::function<void(P...)> func) { *this = std::move(func); }
+	synchronized_callback(std::function<void(Args...)> func) { *this = std::move(func); }
 	~synchronized_callback() { *this = nullptr; }
 
 	synchronized_callback &operator=(synchronized_callback &&cb) {
@@ -102,16 +123,16 @@ public:
 		return *this;
 	}
 
-	synchronized_callback &operator=(std::function<void(P...)> func) {
+	synchronized_callback &operator=(std::function<void(Args...)> func) {
 		std::lock_guard lock(mutex);
 		callback = std::move(func);
 		return *this;
 	}
 
-	void operator()(P... args) const {
+	void operator()(Args... args) const {
 		std::lock_guard lock(mutex);
 		if (callback)
-			callback(args...);
+			callback(std::move(args)...);
 	}
 
 	operator bool() const {
@@ -119,10 +140,14 @@ public:
 		return callback ? true : false;
 	}
 
+	std::function<void(Args...)> wrap() const {
+		return [this](Args... args) { (*this)(std::move(args)...); };
+	}
+
 private:
-	std::function<void(P...)> callback;
+	std::function<void(Args...)> callback;
 	mutable std::recursive_mutex mutex;
 };
-}
+} // namespace rtc
 
 #endif

include/rtc/log.hpp

@@ -49,6 +49,6 @@ enum class LogLevel { // Don't change, it must match plog severity
 
 void InitLogger(LogLevel level);
 void InitLogger(plog::Severity severity, plog::IAppender *appender = nullptr);
-}
+} // namespace rtc
 
 #endif

include/rtc/message.hpp

@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2019 Paul-Louis Ageneau
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -24,6 +24,8 @@
 
 #include <functional>
 #include <memory>
+#include <optional>
+#include <variant>
 
 namespace rtc {
 
@@ -46,8 +48,9 @@ struct Message : binary {
 
 using message_ptr = std::shared_ptr<Message>;
 using message_callback = std::function<void(message_ptr message)>;
+using message_variant = std::variant<binary, string>;
 
-constexpr auto message_size_func = [](const message_ptr &m) -> size_t {
+inline size_t message_size_func(const message_ptr &m) {
 	return m->type == Message::Binary || m->type == Message::String ? m->size() : 0;
 };
 
@@ -61,23 +64,16 @@ message_ptr make_message(Iterator begin, Iterator end, Message::Type type = Mess
 	return message;
 }
 
-inline message_ptr make_message(size_t size, Message::Type type = Message::Binary,
-                                unsigned int stream = 0,
-                                std::shared_ptr<Reliability> reliability = nullptr) {
-	auto message = std::make_shared<Message>(size, type);
-	message->stream = stream;
-	message->reliability = reliability;
-	return message;
-}
+message_ptr make_message(size_t size, Message::Type type = Message::Binary, unsigned int stream = 0,
+                         std::shared_ptr<Reliability> reliability = nullptr);
 
-inline message_ptr make_message(binary &&data, Message::Type type = Message::Binary,
+message_ptr make_message(binary &&data, Message::Type type = Message::Binary,
                          unsigned int stream = 0,
-                                std::shared_ptr<Reliability> reliability = nullptr) {
-	auto message = std::make_shared<Message>(std::move(data), type);
-	message->stream = stream;
-	message->reliability = reliability;
-	return message;
-}
+                         std::shared_ptr<Reliability> reliability = nullptr);
+
+message_ptr make_message(message_variant data);
+
+message_variant to_variant(Message &&message);
 
 } // namespace rtc
 

include/rtc/peerconnection.hpp

@@ -28,6 +28,7 @@
 #include "message.hpp"
 #include "reliability.hpp"
 #include "rtc.hpp"
+#include "track.hpp"
 
 #include <atomic>
 #include <functional>
@@ -49,6 +50,13 @@ class SctpTransport;
 using certificate_ptr = std::shared_ptr<Certificate>;
 using future_certificate_ptr = std::shared_future<certificate_ptr>;
 
+struct DataChannelInit {
+	Reliability reliability = {};
+	bool negotiated = false;
+	std::optional<uint16_t> id = nullopt;
+	string protocol = "";
+};
+
 class PeerConnection final : public std::enable_shared_from_this<PeerConnection> {
 public:
 	enum class State : int {
@@ -66,7 +74,15 @@ public:
 		Complete = RTC_GATHERING_COMPLETE
 	};
 
-	PeerConnection(void);
+	enum class SignalingState : int {
+		Stable = RTC_SIGNALING_STABLE,
+		HaveLocalOffer = RTC_SIGNALING_HAVE_LOCAL_OFFER,
+		HaveRemoteOffer = RTC_SIGNALING_HAVE_REMOTE_OFFER,
+		HaveLocalPranswer = RTC_SIGNALING_HAVE_LOCAL_PRANSWER,
+		HaveRemotePranswer = RTC_SIGNALING_HAVE_REMOTE_PRANSWER,
+	} rtcSignalingState;
+
+	PeerConnection();
 	PeerConnection(const Configuration &config);
 	~PeerConnection();
 
@@ -75,23 +91,32 @@ public:
 	const Configuration *config() const;
 	State state() const;
 	GatheringState gatheringState() const;
+	SignalingState signalingState() const;
+	bool hasLocalDescription() const;
+	bool hasRemoteDescription() const;
+	bool hasMedia() const;
 	std::optional<Description> localDescription() const;
 	std::optional<Description> remoteDescription() const;
 	std::optional<string> localAddress() const;
 	std::optional<string> remoteAddress() const;
+	bool getSelectedCandidatePair(Candidate *local, Candidate *remote);
+
+	void setLocalDescription(Description::Type type = Description::Type::Unspec);
 
-	void setLocalDescription(std::optional<Description> description = nullopt);
 	void setRemoteDescription(Description description);
 	void addRemoteCandidate(Candidate candidate);
 
-	std::shared_ptr<DataChannel> createDataChannel(const string &label, const string &protocol = "",
-	                                               const Reliability &reliability = {});
+	std::shared_ptr<DataChannel> addDataChannel(string label, DataChannelInit init = {});
+
+	// Equivalent to calling addDataChannel() and setLocalDescription()
+	std::shared_ptr<DataChannel> createDataChannel(string label, DataChannelInit init = {});
 
 	void onDataChannel(std::function<void(std::shared_ptr<DataChannel> dataChannel)> callback);
-	void onLocalDescription(std::function<void(const Description &description)> callback);
-	void onLocalCandidate(std::function<void(const Candidate &candidate)> callback);
+	void onLocalDescription(std::function<void(Description description)> callback);
+	void onLocalCandidate(std::function<void(Candidate candidate)> callback);
 	void onStateChange(std::function<void(State state)> callback);
 	void onGatheringStateChange(std::function<void(GatheringState state)> callback);
+	void onSignalingStateChange(std::function<void(SignalingState state)> callback);
 
 	// Stats
 	void clearStats();
@@ -99,18 +124,12 @@ public:
 	size_t bytesReceived();
 	std::optional<std::chrono::milliseconds> rtt();
 
-	// Media
-	bool hasMedia() const;
-	void sendMedia(const binary &packet);
-	void sendMedia(const byte *packet, size_t size);
-
-	void onMedia(std::function<void(const binary &packet)> callback);
-
-	// libnice only
-	bool getSelectedCandidatePair(CandidateInfo *local, CandidateInfo *remote);
+	// Track media support requires compiling with libSRTP
+	std::shared_ptr<Track> addTrack(Description::Media description);
+	void onTrack(std::function<void(std::shared_ptr<Track> track)> callback);
 
 private:
-	std::shared_ptr<IceTransport> initIceTransport(Description::Role role);
+	std::shared_ptr<IceTransport> initIceTransport();
 	std::shared_ptr<DtlsTransport> initDtlsTransport();
 	std::shared_ptr<SctpTransport> initSctpTransport();
 	void closeTransports();
@@ -120,21 +139,29 @@ private:
 	void forwardMessage(message_ptr message);
 	void forwardMedia(message_ptr message);
 	void forwardBufferedAmount(uint16_t stream, size_t amount);
+	std::optional<std::string> getMidFromSsrc(uint32_t ssrc);
 
-	std::shared_ptr<DataChannel> emplaceDataChannel(Description::Role role, const string &label,
-	                                                const string &protocol,
-	                                                const Reliability &reliability);
+	std::shared_ptr<DataChannel> emplaceDataChannel(Description::Role role, string label,
+	                                                DataChannelInit init);
 	std::shared_ptr<DataChannel> findDataChannel(uint16_t stream);
 	void iterateDataChannels(std::function<void(std::shared_ptr<DataChannel> channel)> func);
 	void openDataChannels();
 	void closeDataChannels();
 	void remoteCloseDataChannels();
 
+	void incomingTrack(Description::Media description);
+	void openTracks();
+
+	void validateRemoteDescription(const Description &description);
 	void processLocalDescription(Description description);
 	void processLocalCandidate(Candidate candidate);
+	void processRemoteDescription(Description description);
+	void processRemoteCandidate(Candidate candidate);
 	void triggerDataChannel(std::weak_ptr<DataChannel> weakDataChannel);
+	void triggerTrack(std::shared_ptr<Track> track);
 	bool changeState(State state);
 	bool changeGatheringState(GatheringState state);
+	bool changeSignalingState(SignalingState state);
 
 	void resetCallbacks();
 
@@ -146,29 +173,38 @@ private:
 	const std::unique_ptr<Processor> mProcessor;
 
 	std::optional<Description> mLocalDescription, mRemoteDescription;
+	std::optional<Description> mCurrentLocalDescription;
 	mutable std::mutex mLocalDescriptionMutex, mRemoteDescriptionMutex;
 
 	std::shared_ptr<IceTransport> mIceTransport;
 	std::shared_ptr<DtlsTransport> mDtlsTransport;
 	std::shared_ptr<SctpTransport> mSctpTransport;
 
-	std::unordered_map<unsigned int, std::weak_ptr<DataChannel>> mDataChannels;
-	std::shared_mutex mDataChannelsMutex;
+	std::unordered_map<uint16_t, std::weak_ptr<DataChannel>> mDataChannels; // by stream ID
+	std::unordered_map<string, std::weak_ptr<Track>> mTracks;               // by mid
+	std::vector<std::weak_ptr<Track>> mTrackLines;                          // by SDP order
+	std::shared_mutex mDataChannelsMutex, mTracksMutex;
+
+	std::unordered_map<uint32_t, string> mMidFromSsrc; // cache
 
 	std::atomic<State> mState;
 	std::atomic<GatheringState> mGatheringState;
+	std::atomic<SignalingState> mSignalingState;
+	std::atomic<bool> mNegotiationNeeded;
 
 	synchronized_callback<std::shared_ptr<DataChannel>> mDataChannelCallback;
-	synchronized_callback<const Description &> mLocalDescriptionCallback;
-	synchronized_callback<const Candidate &> mLocalCandidateCallback;
+	synchronized_callback<Description> mLocalDescriptionCallback;
+	synchronized_callback<Candidate> mLocalCandidateCallback;
 	synchronized_callback<State> mStateChangeCallback;
 	synchronized_callback<GatheringState> mGatheringStateChangeCallback;
-	synchronized_callback<const binary &> mMediaCallback;
+	synchronized_callback<SignalingState> mSignalingStateChangeCallback;
+	synchronized_callback<std::shared_ptr<Track>> mTrackCallback;
 };
 
 } // namespace rtc
 
-std::ostream &operator<<(std::ostream &out, const rtc::PeerConnection::State &state);
-std::ostream &operator<<(std::ostream &out, const rtc::PeerConnection::GatheringState &state);
+std::ostream &operator<<(std::ostream &out, rtc::PeerConnection::State state);
+std::ostream &operator<<(std::ostream &out, rtc::PeerConnection::GatheringState state);
+std::ostream &operator<<(std::ostream &out, rtc::PeerConnection::SignalingState state);
 
 #endif

include/rtc/queue.hpp

@@ -38,16 +38,22 @@ public:
 	~Queue();
 
 	void stop();
+	bool running() const;
 	bool empty() const;
+	bool full() const;
 	size_t size() const;   // elements
 	size_t amount() const; // amount
 	void push(T element);
 	std::optional<T> pop();
+	std::optional<T> tryPop();
 	std::optional<T> peek();
 	std::optional<T> exchange(T element);
 	bool wait(const std::optional<std::chrono::milliseconds> &duration = nullopt);
 
 private:
+	void pushImpl(T element);
+	std::optional<T> popImpl();
+
 	const size_t mLimit;
 	size_t mAmount;
 	std::queue<T> mQueue;
@@ -75,11 +81,21 @@ template <typename T> void Queue<T>::stop() {
 	mPushCondition.notify_all();
 }
 
+template <typename T> bool Queue<T>::running() const {
+	std::lock_guard lock(mMutex);
+	return !mQueue.empty() || !mStopping;
+}
+
 template <typename T> bool Queue<T>::empty() const {
 	std::lock_guard lock(mMutex);
 	return mQueue.empty();
 }
 
+template <typename T> bool Queue<T>::full() const {
+	std::lock_guard lock(mMutex);
+	return mQueue.size() >= mLimit;
+}
+
 template <typename T> size_t Queue<T>::size() const {
 	std::lock_guard lock(mMutex);
 	return mQueue.size();
@@ -93,43 +109,32 @@ template <typename T> size_t Queue<T>::amount() const {
 template <typename T> void Queue<T>::push(T element) {
 	std::unique_lock lock(mMutex);
 	mPushCondition.wait(lock, [this]() { return !mLimit || mQueue.size() < mLimit || mStopping; });
-	if (!mStopping) {
-		mAmount += mAmountFunction(element);
-		mQueue.emplace(std::move(element));
-		mPopCondition.notify_one();
-	}
+	pushImpl(std::move(element));
 }
 
 template <typename T> std::optional<T> Queue<T>::pop() {
 	std::unique_lock lock(mMutex);
 	mPopCondition.wait(lock, [this]() { return !mQueue.empty() || mStopping; });
-	if (!mQueue.empty()) {
-		mAmount -= mAmountFunction(mQueue.front());
-		std::optional<T> element{std::move(mQueue.front())};
-		mQueue.pop();
-		return element;
-	} else {
-		return nullopt;
-	}
+	return popImpl();
+}
+
+template <typename T> std::optional<T> Queue<T>::tryPop() {
+	std::unique_lock lock(mMutex);
+	return popImpl();
 }
 
 template <typename T> std::optional<T> Queue<T>::peek() {
 	std::unique_lock lock(mMutex);
-	if (!mQueue.empty()) {
-		return std::optional<T>{mQueue.front()};
-	} else {
-		return nullopt;
-	}
+	return !mQueue.empty() ? std::make_optional(mQueue.front()) : nullopt;
 }
 
 template <typename T> std::optional<T> Queue<T>::exchange(T element) {
 	std::unique_lock lock(mMutex);
-	if (!mQueue.empty()) {
-		std::swap(mQueue.front(), element);
-		return std::optional<T>{element};
-	} else {
+	if (mQueue.empty())
 		return nullopt;
-	}
+
+	std::swap(mQueue.front(), element);
+	return std::make_optional(std::move(element));
 }
 
 template <typename T>
@@ -139,10 +144,29 @@ bool Queue<T>::wait(const std::optional<std::chrono::milliseconds> &duration) {
 		mPopCondition.wait_for(lock, *duration, [this]() { return !mQueue.empty() || mStopping; });
 	else
 		mPopCondition.wait(lock, [this]() { return !mQueue.empty() || mStopping; });
-	return !mStopping;
+
+	return !mQueue.empty();
+}
+
+template <typename T> void Queue<T>::pushImpl(T element) {
+	if (mStopping)
+		return;
+
+	mAmount += mAmountFunction(element);
+	mQueue.emplace(std::move(element));
+	mPopCondition.notify_one();
+}
+
+template <typename T> std::optional<T> Queue<T>::popImpl() {
+	if (mQueue.empty())
+		return nullopt;
+
+	mAmount -= mAmountFunction(mQueue.front());
+	std::optional<T> element{std::move(mQueue.front())};
+	mQueue.pop();
+	return element;
 }
 
 } // namespace rtc
 
 #endif
-

include/rtc/reliability.hpp

@@ -27,13 +27,9 @@
 namespace rtc {
 
 struct Reliability {
-	enum Type : uint8_t {
-		TYPE_RELIABLE = 0x00,
-		TYPE_PARTIAL_RELIABLE_REXMIT = 0x01,
-		TYPE_PARTIAL_RELIABLE_TIMED = 0x02,
-	};
+	enum class Type { Reliable = 0, Rexmit, Timed };
 
-	Type type = TYPE_RELIABLE;
+	Type type = Type::Reliable;
 	bool unordered = false;
 	std::variant<int, std::chrono::milliseconds> rexmit = 0;
 };
@@ -41,4 +37,3 @@ struct Reliability {
 } // namespace rtc
 
 #endif
-

include/rtc/rtc.h

@@ -25,12 +25,14 @@ extern "C" {
 
 #ifdef _WIN32
 #define RTC_EXPORT __declspec(dllexport)
+#ifdef CAPI_STDCALL
+#define RTC_API __stdcall
 #else
-#define RTC_EXPORT
+#define RTC_API
 #endif
-
-#ifndef RTC_ENABLE_MEDIA
-#define RTC_ENABLE_MEDIA 1
+#else // not WIN32
+#define RTC_EXPORT
+#define RTC_API
 #endif
 
 #ifndef RTC_ENABLE_WEBSOCKET
@@ -57,6 +59,14 @@ typedef enum {
 	RTC_GATHERING_COMPLETE = 2
 } rtcGatheringState;
 
+typedef enum {
+	RTC_SIGNALING_STABLE = 0,
+	RTC_SIGNALING_HAVE_LOCAL_OFFER = 1,
+	RTC_SIGNALING_HAVE_REMOTE_OFFER = 2,
+	RTC_SIGNALING_HAVE_LOCAL_PRANSWER = 3,
+	RTC_SIGNALING_HAVE_REMOTE_PRANSWER = 4,
+} rtcSignalingState;
+
 typedef enum { // Don't change, it must match plog severity
 	RTC_LOG_NONE = 0,
 	RTC_LOG_FATAL = 1,
@@ -70,6 +80,8 @@ typedef enum { // Don't change, it must match plog severity
 #define RTC_ERR_SUCCESS 0
 #define RTC_ERR_INVALID -1   // invalid argument
 #define RTC_ERR_FAILURE -2   // runtime error
+#define RTC_ERR_NOT_AVAIL -3 // element not available
+#define RTC_ERR_TOO_SMALL -4 // buffer too small
 
 typedef struct {
 	const char **iceServers;
@@ -78,21 +90,41 @@ typedef struct {
 	uint16_t portRangeEnd;
 } rtcConfiguration;
 
-typedef void (*rtcLogCallbackFunc)(rtcLogLevel level, const char *message);
-typedef void (*rtcDataChannelCallbackFunc)(int dc, void *ptr);
-typedef void (*rtcDescriptionCallbackFunc)(const char *sdp, const char *type, void *ptr);
-typedef void (*rtcCandidateCallbackFunc)(const char *cand, const char *mid, void *ptr);
-typedef void (*rtcStateChangeCallbackFunc)(rtcState state, void *ptr);
-typedef void (*rtcGatheringStateCallbackFunc)(rtcGatheringState state, void *ptr);
-typedef void (*rtcOpenCallbackFunc)(void *ptr);
-typedef void (*rtcClosedCallbackFunc)(void *ptr);
-typedef void (*rtcErrorCallbackFunc)(const char *error, void *ptr);
-typedef void (*rtcMessageCallbackFunc)(const char *message, int size, void *ptr);
-typedef void (*rtcBufferedAmountLowCallbackFunc)(void *ptr);
-typedef void (*rtcAvailableCallbackFunc)(void *ptr);
+typedef struct {
+	bool unordered;
+	bool unreliable;
+	unsigned int maxPacketLifeTime; // ignored if reliable
+	unsigned int maxRetransmits;    // ignored if reliable
+} rtcReliability;
+
+typedef struct {
+	rtcReliability reliability;
+	const char *protocol; // empty string if NULL
+	bool negotiated;
+	bool manualStream;
+	uint16_t stream; // numeric ID 0-65534, ignored if manualStream is false
+} rtcDataChannelInit;
+
+typedef void(RTC_API *rtcLogCallbackFunc)(rtcLogLevel level, const char *message);
+typedef void(RTC_API *rtcDescriptionCallbackFunc)(int pc, const char *sdp, const char *type,
+                                                  void *ptr);
+typedef void(RTC_API *rtcCandidateCallbackFunc)(int pc, const char *cand, const char *mid,
+                                                void *ptr);
+typedef void(RTC_API *rtcStateChangeCallbackFunc)(int pc, rtcState state, void *ptr);
+typedef void(RTC_API *rtcGatheringStateCallbackFunc)(int pc, rtcGatheringState state, void *ptr);
+typedef void(RTC_API *rtcSignalingStateCallbackFunc)(int pc, rtcSignalingState state, void *ptr);
+typedef void(RTC_API *rtcDataChannelCallbackFunc)(int pc, int dc, void *ptr);
+typedef void(RTC_API *rtcTrackCallbackFunc)(int pc, int tr, void *ptr);
+typedef void(RTC_API *rtcOpenCallbackFunc)(int id, void *ptr);
+typedef void(RTC_API *rtcClosedCallbackFunc)(int id, void *ptr);
+typedef void(RTC_API *rtcErrorCallbackFunc)(int id, const char *error, void *ptr);
+typedef void(RTC_API *rtcMessageCallbackFunc)(int id, const char *message, int size, void *ptr);
+typedef void(RTC_API *rtcBufferedAmountLowCallbackFunc)(int id, void *ptr);
+typedef void(RTC_API *rtcAvailableCallbackFunc)(int id, void *ptr);
 
 // Log
-RTC_EXPORT void rtcInitLogger(rtcLogLevel level, rtcLogCallbackFunc cb); // NULL cb to log to stdout
+// NULL cb on the first call will log to stdout
+RTC_EXPORT void rtcInitLogger(rtcLogLevel level, rtcLogCallbackFunc cb);
 
 // User pointer
 RTC_EXPORT void rtcSetUserPointer(int id, void *ptr);
@@ -101,23 +133,47 @@ RTC_EXPORT void rtcSetUserPointer(int id, void *ptr);
 RTC_EXPORT int rtcCreatePeerConnection(const rtcConfiguration *config); // returns pc id
 RTC_EXPORT int rtcDeletePeerConnection(int pc);
 
-RTC_EXPORT int rtcSetDataChannelCallback(int pc, rtcDataChannelCallbackFunc cb);
 RTC_EXPORT int rtcSetLocalDescriptionCallback(int pc, rtcDescriptionCallbackFunc cb);
 RTC_EXPORT int rtcSetLocalCandidateCallback(int pc, rtcCandidateCallbackFunc cb);
 RTC_EXPORT int rtcSetStateChangeCallback(int pc, rtcStateChangeCallbackFunc cb);
 RTC_EXPORT int rtcSetGatheringStateChangeCallback(int pc, rtcGatheringStateCallbackFunc cb);
+RTC_EXPORT int rtcSetSignalingStateChangeCallback(int pc, rtcSignalingStateCallbackFunc cb);
 
+RTC_EXPORT int rtcSetLocalDescription(int pc, const char *type);
 RTC_EXPORT int rtcSetRemoteDescription(int pc, const char *sdp, const char *type);
 RTC_EXPORT int rtcAddRemoteCandidate(int pc, const char *cand, const char *mid);
 
+RTC_EXPORT int rtcGetLocalDescription(int pc, char *buffer, int size);
+RTC_EXPORT int rtcGetRemoteDescription(int pc, char *buffer, int size);
+
 RTC_EXPORT int rtcGetLocalAddress(int pc, char *buffer, int size);
 RTC_EXPORT int rtcGetRemoteAddress(int pc, char *buffer, int size);
 
+RTC_EXPORT int rtcGetSelectedCandidatePair(int pc, char *local, int localSize, char *remote,
+                                           int remoteSize);
+
 // DataChannel
+RTC_EXPORT int rtcSetDataChannelCallback(int pc, rtcDataChannelCallbackFunc cb);
+RTC_EXPORT int rtcAddDataChannel(int pc, const char *label); // returns dc id
+RTC_EXPORT int rtcAddDataChannelEx(int pc, const char *label,
+                                   const rtcDataChannelInit *init); // returns dc id
+// Equivalent to calling rtcAddDataChannel() and rtcSetLocalDescription()
 RTC_EXPORT int rtcCreateDataChannel(int pc, const char *label); // returns dc id
+RTC_EXPORT int rtcCreateDataChannelEx(int pc, const char *label,
+                                      const rtcDataChannelInit *init); // returns dc id
 RTC_EXPORT int rtcDeleteDataChannel(int dc);
 
+RTC_EXPORT int rtcGetDataChannelStream(int dc);
 RTC_EXPORT int rtcGetDataChannelLabel(int dc, char *buffer, int size);
+RTC_EXPORT int rtcGetDataChannelProtocol(int dc, char *buffer, int size);
+RTC_EXPORT int rtcGetDataChannelReliability(int dc, rtcReliability *reliability);
+
+// Track
+RTC_EXPORT int rtcSetTrackCallback(int pc, rtcTrackCallbackFunc cb);
+RTC_EXPORT int rtcAddTrack(int pc, const char *mediaDescriptionSdp); // returns tr id
+RTC_EXPORT int rtcDeleteTrack(int tr);
+
+RTC_EXPORT int rtcGetTrackDescription(int tr, char *buffer, int size);
 
 // WebSocket
 #if RTC_ENABLE_WEBSOCKET
@@ -130,7 +186,7 @@ RTC_EXPORT int rtcCreateWebSocketEx(const char *url, const rtcWsConfiguration *c
 RTC_EXPORT int rtcDeleteWebsocket(int ws);
 #endif
 
-// DataChannel and WebSocket common API
+// DataChannel, Track, and WebSocket common API
 RTC_EXPORT int rtcSetOpenCallback(int id, rtcOpenCallbackFunc cb);
 RTC_EXPORT int rtcSetClosedCallback(int id, rtcClosedCallbackFunc cb);
 RTC_EXPORT int rtcSetErrorCallback(int id, rtcErrorCallbackFunc cb);
@@ -141,7 +197,7 @@ RTC_EXPORT int rtcGetBufferedAmount(int id); // total size buffered to send
 RTC_EXPORT int rtcSetBufferedAmountLowThreshold(int id, int amount);
 RTC_EXPORT int rtcSetBufferedAmountLowCallback(int id, rtcBufferedAmountLowCallbackFunc cb);
 
-// DataChannel and WebSocket common extended API
+// DataChannel, Track, and WebSocket common extended API
 RTC_EXPORT int rtcGetAvailableAmount(int id); // total size available to receive
 RTC_EXPORT int rtcSetAvailableCallback(int id, rtcAvailableCallbackFunc cb);
 RTC_EXPORT int rtcReceiveMessage(int id, char *buffer, int *size);

include/rtc/rtc.hpp

@@ -27,4 +27,3 @@
 
 // C API
 #include "rtc.h"
-

include/rtc/rtcp.hpp

@@ -0,0 +1,91 @@
+/**
+ * Copyright (c) 2020 Staz Modrzynski
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_RTCP_H
+#define RTC_RTCP_H
+
+#include <utility>
+
+#include "include.hpp"
+#include "log.hpp"
+#include "message.hpp"
+#include "rtp.hpp"
+
+namespace rtc {
+
+class RtcpHandler {
+protected:
+	/**
+	 * Use this callback when trying to send custom data (such as RTCP) to the client.
+	 */
+	synchronized_callback<rtc::message_ptr> outgoingCallback;
+
+public:
+	/**
+	 * Called when there is traffic coming from the peer
+	 * @param ptr
+	 * @return
+	 */
+	virtual rtc::message_ptr incoming(rtc::message_ptr ptr) = 0;
+
+	/**
+	 * Called when there is traffic that needs to be sent to the peer
+	 * @param ptr
+	 * @return
+	 */
+	virtual rtc::message_ptr outgoing(rtc::message_ptr ptr) = 0;
+
+	/**
+	 * This callback is used to send traffic back to the peer.
+	 * This callback skips calling the track's methods.
+	 * @param cb
+	 */
+	void onOutgoing(const std::function<void(rtc::message_ptr)> &cb);
+
+	virtual bool requestKeyframe() { return false; }
+};
+
+class Track;
+
+// An RtcpSession can be plugged into a Track to handle the whole RTCP session
+class RtcpReceivingSession : public RtcpHandler {
+public:
+	rtc::message_ptr incoming(rtc::message_ptr ptr) override;
+	rtc::message_ptr outgoing(rtc::message_ptr ptr) override;
+	bool send(rtc::message_ptr ptr);
+
+	void requestBitrate(unsigned int newBitrate);
+
+	bool requestKeyframe() override;
+
+protected:
+	void pushREMB(unsigned int bitrate);
+	void pushRR(unsigned int lastSR_delay);
+
+	void pushPLI();
+
+	unsigned int mRequestedBitrate = 0;
+	SSRC mSsrc = 0;
+	uint32_t mGreatestSeqNo = 0;
+	uint64_t mSyncRTPTS, mSyncNTPTS;
+};
+
+} // namespace rtc
+
+#endif // RTC_RTCP_H

include/rtc/rtp.hpp

@@ -0,0 +1,505 @@
+/**
+ * Copyright (c) 2020 Staz Modrzynski
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_RTP_HPP
+#define RTC_RTP_HPP
+
+#include <rtc/log.hpp>
+
+#include <cmath>
+
+#ifdef _WIN32
+#include <winsock2.h>
+#else
+#include <arpa/inet.h>
+#endif
+
+#ifndef htonll
+#define htonll(x)                                                                                  \
+	((uint64_t)htonl(((uint64_t)(x)&0xFFFFFFFF) << 32) | (uint64_t)htonl((uint64_t)(x) >> 32))
+#endif
+#ifndef ntohll
+#define ntohll(x) htonll(x)
+#endif
+
+namespace rtc {
+
+typedef uint32_t SSRC;
+
+#pragma pack(push, 1)
+
+struct RTP {
+private:
+	uint8_t _first;
+	uint8_t _payloadType;
+	uint16_t _seqNumber;
+	uint32_t _timestamp;
+	SSRC _ssrc;
+
+public:
+	SSRC csrc[16];
+
+	inline uint8_t version() const { return _first >> 6; }
+	inline bool padding() const { return (_first >> 5) & 0x01; }
+	inline bool extension() const { return (_first >> 4) & 0x01; }
+	inline uint8_t csrcCount() const { return _first & 0x0F; }
+	inline uint8_t marker() const { return _payloadType & 0b10000000; }
+	inline uint8_t payloadType() const { return _payloadType & 0b01111111; }
+	inline uint16_t seqNumber() const { return ntohs(_seqNumber); }
+	inline uint32_t timestamp() const { return ntohl(_timestamp); }
+	inline uint32_t ssrc() const { return ntohl(_ssrc); }
+
+	inline size_t getSize() const {
+		return ((char *)&csrc) - ((char *)this) + sizeof(SSRC) * csrcCount();
+	}
+
+	char *getBody() const { return ((char *)&csrc) + sizeof(SSRC) * csrcCount(); }
+
+	inline void setSeqNumber(uint16_t newSeqNo) { _seqNumber = htons(newSeqNo); }
+	inline void setPayloadType(uint8_t newPayloadType) {
+		_payloadType = (_payloadType & 0b10000000u) | (0b01111111u & newPayloadType);
+	}
+	inline void setSsrc(uint32_t ssrc) { _ssrc = htonl(ssrc); }
+
+	void setTimestamp(uint32_t i) { _timestamp = htonl(i); }
+
+	void log() {
+		PLOG_VERBOSE  << "RTP V: " << (int) version()
+		            << " P: " << (padding() ? "P" : " ")
+		            << " X: " << (extension() ? "X" : " ")
+		            << " CC: "  << (int) csrcCount()
+		            << " M: " << (marker() ? "M" : " ")
+		            << " PT: " << (int) payloadType()
+		            << " SEQNO: " << seqNumber()
+		            << " TS: " << timestamp();
+	}
+};
+
+struct RTCP_ReportBlock {
+	SSRC ssrc;
+
+private:
+	uint32_t _fractionLostAndPacketsLost; // fraction lost is 8-bit, packets lost is 24-bit
+	uint16_t _seqNoCycles;
+	uint16_t _highestSeqNo;
+	uint32_t _jitter;
+	uint32_t _lastReport;
+	uint32_t _delaySinceLastReport;
+
+public:
+	inline void preparePacket(SSRC ssrc, [[maybe_unused]] unsigned int packetsLost,
+	                          [[maybe_unused]] unsigned int totalPackets, uint16_t highestSeqNo,
+	                          uint16_t seqNoCycles, uint32_t jitter, uint64_t lastSR_NTP,
+	                          uint64_t lastSR_DELAY) {
+		setSeqNo(highestSeqNo, seqNoCycles);
+		setJitter(jitter);
+		setSSRC(ssrc);
+
+		// Middle 32 bits of NTP Timestamp
+		//		  this->lastReport = lastSR_NTP >> 16u;
+		setNTPOfSR(uint64_t(lastSR_NTP));
+		setDelaySinceSR(uint32_t(lastSR_DELAY));
+
+		// The delay, expressed in units of 1/65536 seconds
+		//		  this->delaySinceLastReport = lastSR_DELAY;
+	}
+
+	inline void setSSRC(SSRC ssrc) { this->ssrc = htonl(ssrc); }
+	inline SSRC getSSRC() const { return ntohl(ssrc); }
+
+	inline void setPacketsLost([[maybe_unused]] unsigned int packetsLost,
+	                           [[maybe_unused]] unsigned int totalPackets) {
+		// TODO Implement loss percentages.
+		_fractionLostAndPacketsLost = 0;
+	}
+	inline unsigned int getLossPercentage() const {
+		// TODO Implement loss percentages.
+		return 0;
+	}
+	inline unsigned int getPacketLostCount() const {
+		// TODO Implement total packets lost.
+		return 0;
+	}
+
+	inline uint16_t seqNoCycles() const { return ntohs(_seqNoCycles); }
+	inline uint16_t highestSeqNo() const { return ntohs(_highestSeqNo); }
+	inline uint32_t jitter() const { return ntohl(_jitter); }
+
+	inline void setSeqNo(uint16_t highestSeqNo, uint16_t seqNoCycles) {
+		_highestSeqNo = htons(highestSeqNo);
+		_seqNoCycles = htons(seqNoCycles);
+	}
+
+	inline void setJitter(uint32_t jitter) { _jitter = htonl(jitter); }
+
+	inline void setNTPOfSR(uint64_t ntp) { _lastReport = htonll(ntp >> 16u); }
+	inline uint32_t getNTPOfSR() const { return ntohl(_lastReport) << 16u; }
+
+	inline void setDelaySinceSR(uint32_t sr) {
+		// The delay, expressed in units of 1/65536 seconds
+		_delaySinceLastReport = htonl(sr);
+	}
+	inline uint32_t getDelaySinceSR() const { return ntohl(_delaySinceLastReport); }
+
+	inline void log() const {
+		PLOG_VERBOSE << "RTCP report block: "
+		             << "ssrc="
+		             << ntohl(ssrc)
+		             // TODO: Implement these reports
+		             //	<< ", fractionLost=" << fractionLost
+		             //	<< ", packetsLost=" << packetsLost
+		             << ", highestSeqNo=" << highestSeqNo() << ", seqNoCycles=" << seqNoCycles()
+		             << ", jitter=" << jitter() << ", lastSR=" << getNTPOfSR()
+		             << ", lastSRDelay=" << getDelaySinceSR();
+	}
+};
+
+struct RTCP_HEADER {
+private:
+	uint8_t _first;
+	uint8_t _payloadType;
+	uint16_t _length;
+
+public:
+	inline uint8_t version() const { return _first >> 6; }
+	inline bool padding() const { return (_first >> 5) & 0x01; }
+	inline uint8_t reportCount() const { return _first & 0x0F; }
+	inline uint8_t payloadType() const { return _payloadType; }
+	inline uint16_t length() const { return ntohs(_length); }
+	inline size_t lengthInBytes() const { return (1 + length()) * 4; }
+
+	inline void setPayloadType(uint8_t type) { _payloadType = type; }
+	inline void setReportCount(uint8_t count) {
+		_first = (_first & 0b11100000u) | (count & 0b00011111u);
+	}
+	inline void setLength(uint16_t length) { _length = htons(length); }
+
+	inline void prepareHeader(uint8_t payloadType, uint8_t reportCount, uint16_t length) {
+		_first = 0b10000000; // version 2, no padding
+		setReportCount(reportCount);
+		setPayloadType(payloadType);
+		setLength(length);
+	}
+
+	inline void log() const {
+		PLOG_VERBOSE << "RTCP header: "
+		          << "version=" << unsigned(version()) << ", padding=" << padding()
+		          << ", reportCount=" << unsigned(reportCount())
+		          << ", payloadType=" << unsigned(payloadType()) << ", length=" << length();
+	}
+};
+
+struct RTCP_FB_HEADER {
+	RTCP_HEADER header;
+	SSRC packetSender;
+	SSRC mediaSource;
+
+	[[nodiscard]] SSRC getPacketSenderSSRC() const { return ntohl(packetSender); }
+
+	[[nodiscard]] SSRC getMediaSourceSSRC() const { return ntohl(mediaSource); }
+
+	void setPacketSenderSSRC(SSRC ssrc) { this->packetSender = htonl(ssrc); }
+
+	void setMediaSourceSSRC(SSRC ssrc) { this->mediaSource = htonl(ssrc); }
+
+	void log() {
+		header.log();
+		PLOG_VERBOSE << "FB: "
+		             << " packet sender: " << getPacketSenderSSRC()
+		             << " media source: " << getMediaSourceSSRC();
+	}
+};
+
+struct RTCP_SR {
+	RTCP_HEADER header;
+	SSRC _senderSSRC;
+
+private:
+	uint64_t _ntpTimestamp;
+	uint32_t _rtpTimestamp;
+	uint32_t _packetCount;
+	uint32_t _octetCount;
+
+	RTCP_ReportBlock _reportBlocks;
+
+public:
+	inline void preparePacket(SSRC senderSSRC, uint8_t reportCount) {
+		unsigned int length =
+		    ((sizeof(header) + 24 + reportCount * sizeof(RTCP_ReportBlock)) / 4) - 1;
+		header.prepareHeader(200, reportCount, uint16_t(length));
+		this->_senderSSRC = htonl(senderSSRC);
+	}
+
+	inline RTCP_ReportBlock *getReportBlock(int num) { return &_reportBlocks + num; }
+	inline const RTCP_ReportBlock *getReportBlock(int num) const { return &_reportBlocks + num; }
+
+	[[nodiscard]] inline size_t getSize() const {
+		// "length" in packet is one less than the number of 32 bit words in the packet.
+		return sizeof(uint32_t) * (1 + size_t(header.length()));
+	}
+
+	inline uint64_t ntpTimestamp() const { return ntohll(_ntpTimestamp); }
+	inline uint32_t rtpTimestamp() const { return ntohl(_rtpTimestamp); }
+	inline uint32_t packetCount() const { return ntohl(_packetCount); }
+	inline uint32_t octetCount() const { return ntohl(_octetCount); }
+	inline uint32_t senderSSRC() const { return ntohl(_senderSSRC); }
+
+	inline void setNtpTimestamp(uint32_t ts) { _ntpTimestamp = htonll(ts); }
+	inline void setRtpTimestamp(uint32_t ts) { _rtpTimestamp = htonl(ts); }
+
+	inline void log() const {
+		header.log();
+		PLOG_VERBOSE << "RTCP SR: "
+		             << " SSRC=" << senderSSRC() << ", NTP_TS=" << ntpTimestamp()
+		             << ", RTP_TS=" << rtpTimestamp() << ", packetCount=" << packetCount()
+		             << ", octetCount=" << octetCount();
+
+		for (unsigned i = 0; i < unsigned(header.reportCount()); i++) {
+			getReportBlock(i)->log();
+		}
+	}
+};
+
+struct RTCP_RR {
+	RTCP_HEADER header;
+	SSRC _senderSSRC;
+
+private:
+	RTCP_ReportBlock _reportBlocks;
+
+public:
+	inline RTCP_ReportBlock *getReportBlock(int num) { return &_reportBlocks + num; }
+	inline const RTCP_ReportBlock *getReportBlock(int num) const { return &_reportBlocks + num; }
+
+	inline SSRC senderSSRC() const { return ntohl(_senderSSRC); }
+	inline void setSenderSSRC(SSRC ssrc) { this->_senderSSRC = htonl(ssrc); }
+
+	[[nodiscard]] inline size_t getSize() const {
+		// "length" in packet is one less than the number of 32 bit words in the packet.
+		return sizeof(uint32_t) * (1 + size_t(header.length()));
+	}
+
+	inline void preparePacket(SSRC senderSSRC, uint8_t reportCount) {
+		// "length" in packet is one less than the number of 32 bit words in the packet.
+		size_t length = (sizeWithReportBlocks(reportCount) / 4) - 1;
+		header.prepareHeader(201, reportCount, uint16_t(length));
+		this->_senderSSRC = htonl(senderSSRC);
+	}
+
+	inline static size_t sizeWithReportBlocks(uint8_t reportCount) {
+		return sizeof(header) + 4 + size_t(reportCount) * sizeof(RTCP_ReportBlock);
+	}
+
+	inline bool isSenderReport() { return header.payloadType() == 200; }
+
+	inline bool isReceiverReport() { return header.payloadType() == 201; }
+
+	inline void log() const {
+		header.log();
+		PLOG_VERBOSE << "RTCP RR: "
+		             << " SSRC=" << ntohl(_senderSSRC);
+
+		for (unsigned i = 0; i < unsigned(header.reportCount()); i++) {
+			getReportBlock(i)->log();
+		}
+	}
+};
+
+struct RTCP_REMB {
+	RTCP_FB_HEADER header;
+
+	/*! \brief Unique identifier ('R' 'E' 'M' 'B') */
+	char id[4];
+
+	/*! \brief Num SSRC, Br Exp, Br Mantissa (bit mask) */
+	uint32_t bitrate;
+
+	SSRC ssrc[1];
+
+	[[nodiscard]] unsigned int getSize() const {
+		// "length" in packet is one less than the number of 32 bit words in the packet.
+		return sizeof(uint32_t) * (1 + header.header.length());
+	}
+
+	void preparePacket(SSRC senderSSRC, unsigned int numSSRC, unsigned int bitrate) {
+
+		// Report Count becomes the format here.
+		header.header.prepareHeader(206, 15, 0);
+
+		// Always zero.
+		header.setMediaSourceSSRC(0);
+
+		header.setPacketSenderSSRC(senderSSRC);
+
+		id[0] = 'R';
+		id[1] = 'E';
+		id[2] = 'M';
+		id[3] = 'B';
+
+		setBitrate(numSSRC, bitrate);
+	}
+
+	void setBitrate(unsigned int numSSRC, unsigned int bitrate) {
+		unsigned int exp = 0;
+		while (bitrate > pow(2, 18) - 1) {
+			exp++;
+			bitrate /= 2;
+		}
+
+		// "length" in packet is one less than the number of 32 bit words in the packet.
+		header.header.setLength(
+		    uint16_t((offsetof(RTCP_REMB, ssrc) / sizeof(uint32_t)) - 1 + numSSRC));
+
+		this->bitrate = htonl((numSSRC << (32u - 8u)) | (exp << (32u - 8u - 6u)) | bitrate);
+	}
+
+	void setSsrc(int iterator, SSRC newSssrc) { ssrc[iterator] = htonl(newSssrc); }
+
+	size_t static inline sizeWithSSRCs(int count) {
+		return sizeof(RTCP_REMB) + (count - 1) * sizeof(SSRC);
+	}
+};
+
+struct RTCP_PLI {
+	RTCP_FB_HEADER header;
+
+	void preparePacket(SSRC messageSSRC) {
+		header.header.prepareHeader(206, 1, 2);
+		header.setPacketSenderSSRC(messageSSRC);
+		header.setMediaSourceSSRC(messageSSRC);
+	}
+
+	void print() { header.log(); }
+
+	[[nodiscard]] static unsigned int size() { return sizeof(RTCP_FB_HEADER); }
+};
+
+struct RTCP_FIR_PART {
+	uint32_t ssrc;
+	uint8_t seqNo;
+	uint8_t dummy1;
+	uint16_t dummy2;
+};
+
+struct RTCP_FIR {
+	RTCP_FB_HEADER header;
+	RTCP_FIR_PART parts[1];
+
+	void preparePacket(SSRC messageSSRC, uint8_t seqNo) {
+		header.header.prepareHeader(206, 4, 2 + 2 * 1);
+		header.setPacketSenderSSRC(messageSSRC);
+		header.setMediaSourceSSRC(messageSSRC);
+		parts[0].ssrc = htonl(messageSSRC);
+		parts[0].seqNo = seqNo;
+	}
+
+	void print() { header.log(); }
+
+	[[nodiscard]] static unsigned int size() {
+		return sizeof(RTCP_FB_HEADER) + sizeof(RTCP_FIR_PART);
+	}
+};
+
+struct RTCP_NACK_PART {
+	uint16_t pid;
+	uint16_t blp;
+};
+
+class RTCP_NACK {
+public:
+	RTCP_FB_HEADER header;
+	RTCP_NACK_PART parts[1];
+
+public:
+	void preparePacket(SSRC ssrc, unsigned int discreteSeqNoCount) {
+		header.header.prepareHeader(205, 1, 2 + discreteSeqNoCount);
+		header.setMediaSourceSSRC(ssrc);
+		header.setPacketSenderSSRC(ssrc);
+	}
+
+	/**
+	 * Add a packet to the list of missing packets.
+	 * @param fciCount The number of FCI fields that are present in this packet.
+	 *                  Let the number start at zero and let this function grow the number.
+	 * @param fciPID The seq no of the active FCI. It will be initialized automatically, and will
+	 * change automatically.
+	 * @param missingPacket The seq no of the missing packet. This will be added to the queue.
+	 * @return true if the packet has grown, false otherwise.
+	 */
+	bool addMissingPacket(unsigned int *fciCount, uint16_t *fciPID, const uint16_t &missingPacket) {
+		if (*fciCount == 0 || missingPacket < *fciPID || missingPacket > (*fciPID + 16)) {
+			parts[*fciCount].pid = htons(missingPacket);
+			parts[*fciCount].blp = 0;
+			*fciPID = missingPacket;
+			(*fciCount)++;
+			return true;
+		} else {
+			// TODO SPEEED!
+			parts[(*fciCount) - 1].blp = htons(ntohs(parts[(*fciCount) - 1].blp) |
+			                                   (1u << (unsigned int)(missingPacket - *fciPID)));
+			return false;
+		}
+	}
+
+	[[nodiscard]] static unsigned int getSize(unsigned int discreteSeqNoCount) {
+		return offsetof(RTCP_NACK, parts) + sizeof(RTCP_NACK_PART) * discreteSeqNoCount;
+	}
+
+	[[nodiscard]] unsigned int getSeqNoCount() { return header.header.length() - 2; }
+};
+
+class RTP_RTX {
+private:
+	RTP header;
+
+public:
+	size_t copyTo(RTP *dest, size_t totalSize, uint8_t originalPayloadType) {
+		memmove((char *)dest, (char *)this, header.getSize());
+		dest->setSeqNumber(getOriginalSeqNo());
+		dest->setPayloadType(originalPayloadType);
+		memmove(dest->getBody(), getBody(), getBodySize(totalSize));
+		return totalSize;
+	}
+
+	[[nodiscard]] uint16_t getOriginalSeqNo() const {
+		return ntohs(*(uint16_t *)(header.getBody()));
+	}
+
+	char *getBody() { return header.getBody() + sizeof(uint16_t); }
+
+	size_t getBodySize(size_t totalSize) { return totalSize - ((char *)getBody() - (char *)this); }
+
+	RTP &getHeader() { return header; }
+
+	size_t normalizePacket(size_t totalSize, SSRC originalSSRC, uint8_t originalPayloadType) {
+		header.setSeqNumber(getOriginalSeqNo());
+		header.setSsrc(originalSSRC);
+		header.setPayloadType(originalPayloadType);
+		// TODO, the -12 is the size of the header (which is variable!)
+		memmove(header.getBody(), header.getBody() + sizeof(uint16_t),
+		        totalSize - 12 - sizeof(uint16_t));
+		return totalSize - sizeof(uint16_t);
+	}
+};
+
+#pragma pack(pop)
+
+}; // namespace rtc
+
+#endif

include/rtc/track.hpp

@@ -0,0 +1,87 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_TRACK_H
+#define RTC_TRACK_H
+
+#include "channel.hpp"
+#include "description.hpp"
+#include "include.hpp"
+#include "message.hpp"
+#include "queue.hpp"
+#include "rtcp.hpp"
+
+#include <atomic>
+#include <variant>
+
+namespace rtc {
+
+#if RTC_ENABLE_MEDIA
+class DtlsSrtpTransport;
+#endif
+
+class Track final : public std::enable_shared_from_this<Track>, public Channel {
+public:
+	Track(Description::Media description);
+	~Track() = default;
+
+	string mid() const;
+	Description::Media description() const;
+
+	void setDescription(Description::Media description);
+
+	void close(void) override;
+	bool send(message_variant data) override;
+	bool send(const byte *data, size_t size);
+
+	bool isOpen(void) const override;
+	bool isClosed(void) const override;
+	size_t maxMessageSize() const override;
+
+	// Extended API
+	size_t availableAmount() const override;
+	std::optional<message_variant> receive() override;
+	std::optional<message_variant> peek() override;
+
+	bool requestKeyframe();
+
+	// RTCP handler
+	void setRtcpHandler(std::shared_ptr<RtcpHandler> handler);
+	std::shared_ptr<RtcpHandler> getRtcpHandler();
+
+private:
+#if RTC_ENABLE_MEDIA
+	void open(std::shared_ptr<DtlsSrtpTransport> transport);
+	std::weak_ptr<DtlsSrtpTransport> mDtlsSrtpTransport;
+#endif
+
+	bool outgoing(message_ptr message);
+	void incoming(message_ptr message);
+
+	Description::Media mMediaDescription;
+	std::atomic<bool> mIsClosed = false;
+
+	Queue<message_ptr> mRecvQueue;
+	std::shared_ptr<RtcpHandler> mRtcpHandler;
+
+	friend class PeerConnection;
+};
+
+} // namespace rtc
+
+#endif

include/rtc/websocket.hpp

@@ -58,14 +58,15 @@ public:
 
 	void open(const string &url);
 	void close() override;
-	bool send(const std::variant<binary, string> &data) override;
+	bool send(const message_variant data) override;
 
 	bool isOpen() const override;
 	bool isClosed() const override;
 	size_t maxMessageSize() const override;
 
 	// Extended API
-	std::optional<std::variant<binary, string>> receive() override;
+	std::optional<message_variant> receive() override;
+	std::optional<message_variant> peek() override;
 	size_t availableAmount() const override; // total size available to receive
 
 private:

src/base64.cpp

@@ -25,8 +25,7 @@ namespace rtc {
 using std::to_integer;
 
 string to_base64(const binary &data) {
-	static const char tab[] =
-	    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+	static const char tab[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
 	string out;
 	out.reserve(3 * ((data.size() + 3) / 4));

src/candidate.cpp

@@ -20,15 +20,17 @@
 
 #include <algorithm>
 #include <array>
+#include <cctype>
 #include <sstream>
+#include <unordered_map>
 
 #ifdef _WIN32
 #include <winsock2.h>
 #include <ws2tcpip.h>
 #else
 #include <netdb.h>
-#include <sys/socket.h>
 #include <netinet/in.h>
+#include <sys/socket.h>
 #endif
 
 #include <sys/types.h>
@@ -38,53 +40,117 @@ using std::string;
 
 namespace {
 
-inline bool hasprefix(const string &str, const string &prefix) {
+inline bool match_prefix(const string &str, const string &prefix) {
 	return str.size() >= prefix.size() &&
 	       std::mismatch(prefix.begin(), prefix.end(), str.begin()).first == prefix.end();
 }
 
+inline void trim_begin(string &str) {
+	str.erase(str.begin(),
+	          std::find_if(str.begin(), str.end(), [](char c) { return !std::isspace(c); }));
+}
+
+inline void trim_end(string &str) {
+	str.erase(
+	    std::find_if(str.rbegin(), str.rend(), [](char c) { return !std::isspace(c); }).base(),
+	    str.end());
+}
+
 } // namespace
 
 namespace rtc {
 
-Candidate::Candidate(string candidate, string mid) : mIsResolved(false) {
+Candidate::Candidate()
+    : mFoundation("none"), mComponent(0), mPriority(0), mTypeString("unknown"),
+      mTransportString("unknown"), mType(Type::Unknown), mTransportType(TransportType::Unknown),
+      mNode("0.0.0.0"), mService("9"), mFamily(Family::Unresolved), mPort(0) {}
+
+Candidate::Candidate(string candidate) : Candidate() {
+	if (!candidate.empty())
+		parse(std::move(candidate));
+}
+
+Candidate::Candidate(string candidate, string mid) : Candidate() {
+	if (!candidate.empty())
+		parse(std::move(candidate));
+	if (!mid.empty())
+		mMid.emplace(std::move(mid));
+}
+
+void Candidate::parse(string candidate) {
+	using TypeMap_t = std::unordered_map<string, Type>;
+	using TcpTypeMap_t = std::unordered_map<string, TransportType>;
+
+	static const TypeMap_t TypeMap = {{"host", Type::Host},
+	                                  {"srflx", Type::ServerReflexive},
+	                                  {"prflx", Type::PeerReflexive},
+	                                  {"relay", Type::Relayed}};
+
+	static const TcpTypeMap_t TcpTypeMap = {{"active", TransportType::TcpActive},
+	                                        {"passive", TransportType::TcpPassive},
+	                                        {"so", TransportType::TcpSo}};
+
 	const std::array prefixes{"a=", "candidate:"};
-	for (string prefix : prefixes)
-		if (hasprefix(candidate, prefix))
+	for (const string &prefix : prefixes)
+		if (match_prefix(candidate, prefix))
 			candidate.erase(0, prefix.size());
 
-	mCandidate = std::move(candidate);
-	mMid = std::move(mid);
+	PLOG_VERBOSE << "Parsing candidate: " << candidate;
+
+	// See RFC 8445 for format
+	std::istringstream iss(candidate);
+	string transport, typ_, type;
+	if (!(iss >> mFoundation >> mComponent >> mTransportString >> mPriority &&
+	      iss >> mNode >> mService >> typ_ >> mTypeString && typ_ == "typ"))
+		throw std::invalid_argument("Invalid candidate format");
+
+	std::getline(iss, mTail);
+	trim_begin(mTail);
+	trim_end(mTail);
+
+	if (auto it = TypeMap.find(type); it != TypeMap.end())
+		mType = it->second;
+	else
+		mType = Type::Unknown;
+
+	if (transport == "UDP" || transport == "udp") {
+		mTransportType = TransportType::Udp;
+	} else if (transport == "TCP" || transport == "tcp") {
+		// Peek tail to find TCP type
+		std::istringstream iss(mTail);
+		string tcptype_, tcptype;
+		if (iss >> tcptype_ >> tcptype && tcptype_ == "tcptype") {
+			if (auto it = TcpTypeMap.find(tcptype); it != TcpTypeMap.end())
+				mTransportType = it->second;
+			else
+				mTransportType = TransportType::TcpUnknown;
+
+		} else {
+			mTransportType = TransportType::TcpUnknown;
+		}
+	} else {
+		mTransportType = TransportType::Unknown;
+	}
+}
+
+void Candidate::hintMid(string mid) {
+	if (!mMid)
+		mMid.emplace(std::move(mid));
 }
 
 bool Candidate::resolve(ResolveMode mode) {
-	if (mIsResolved)
-		return true;
-
 	PLOG_VERBOSE << "Resolving candidate (mode="
-				 << (mode == ResolveMode::Simple ? "simple" : "lookup")
-				 << "): " << mCandidate;
+	             << (mode == ResolveMode::Simple ? "simple" : "lookup") << "): " << mNode << ' '
+	             << mService;
 
-	// See RFC 8445 for format
-	std::istringstream iss(mCandidate);
-	int component{0}, priority{0};
-	string foundation, transport, node, service, typ_, type;
-	if (iss >> foundation >> component >> transport >> priority &&
-	    iss >> node >> service >> typ_ >> type && typ_ == "typ") {
-
-		string left;
-		std::getline(iss, left);
-
-		// Try to resolve the node
+	// Try to resolve the node and service
 	struct addrinfo hints = {};
 	hints.ai_family = AF_UNSPEC;
 	hints.ai_flags = AI_ADDRCONFIG;
-		if (transport == "UDP" || transport == "udp") {
+	if (mTransportType == TransportType::Udp) {
 		hints.ai_socktype = SOCK_DGRAM;
 		hints.ai_protocol = IPPROTO_UDP;
-		}
-
-		if (transport == "TCP" || transport == "tcp") {
+	} else if (mTransportType != TransportType::Unknown) {
 		hints.ai_socktype = SOCK_STREAM;
 		hints.ai_protocol = IPPROTO_TCP;
 	}
@@ -93,23 +159,19 @@ bool Candidate::resolve(ResolveMode mode) {
 		hints.ai_flags |= AI_NUMERICHOST;
 
 	struct addrinfo *result = nullptr;
-		if (getaddrinfo(node.c_str(), service.c_str(), &hints, &result) == 0) {
-			for (auto p = result; p; p = p->ai_next)
+	if (getaddrinfo(mNode.c_str(), mService.c_str(), &hints, &result) == 0) {
+		for (auto p = result; p; p = p->ai_next) {
 			if (p->ai_family == AF_INET || p->ai_family == AF_INET6) {
-					// Rewrite the candidate
 				char nodebuffer[MAX_NUMERICNODE_LEN];
 				char servbuffer[MAX_NUMERICSERV_LEN];
 				if (getnameinfo(p->ai_addr, socklen_t(p->ai_addrlen), nodebuffer,
 				                MAX_NUMERICNODE_LEN, servbuffer, MAX_NUMERICSERV_LEN,
 				                NI_NUMERICHOST | NI_NUMERICSERV) == 0) {
-						const char sp{' '};
-						std::ostringstream oss;
-						oss << foundation << sp << component << sp << transport << sp << priority;
-						oss << sp << nodebuffer << sp << servbuffer << sp << "typ" << sp << type;
-						oss << left;
-						mCandidate = oss.str();
-						mIsResolved = true;
-						PLOG_VERBOSE << "Resolved candidate: " << mCandidate;
+
+					mAddress = nodebuffer;
+					mPort = uint16_t(std::stoul(servbuffer));
+					mFamily = p->ai_family == AF_INET6 ? Family::Ipv6 : Family::Ipv4;
+					PLOG_VERBOSE << "Resolved candidate: " << mAddress << ' ' << mPort;
 					break;
 				}
 			}
@@ -118,14 +180,34 @@ bool Candidate::resolve(ResolveMode mode) {
 		freeaddrinfo(result);
 	}
 
-	return mIsResolved;
+	return mFamily != Family::Unresolved;
 }
 
-bool Candidate::isResolved() const { return mIsResolved; }
+Candidate::Type Candidate::type() const { return mType; }
 
-string Candidate::candidate() const { return "candidate:" + mCandidate; }
+Candidate::TransportType Candidate::transportType() const { return mTransportType; }
 
-string Candidate::mid() const { return mMid; }
+uint32_t Candidate::priority() const { return mPriority; }
+
+string Candidate::candidate() const {
+	const char sp{' '};
+	std::ostringstream oss;
+	oss << "candidate:";
+	oss << mFoundation << sp << mComponent << sp << mTransportString << sp << mPriority << sp;
+	if (isResolved())
+		oss << mAddress << sp << mPort;
+	else
+		oss << mNode << sp << mService;
+
+	oss << sp << "typ" << sp << mTypeString;
+
+	if (!mTail.empty())
+		oss << sp << mTail;
+
+	return oss.str();
+}
+
+string Candidate::mid() const { return mMid.value_or("0"); }
 
 Candidate::operator string() const {
 	std::ostringstream line;
@@ -133,38 +215,60 @@ Candidate::operator string() const {
 	return line.str();
 }
 
+bool Candidate::operator==(const Candidate &other) const {
+	return mFoundation == other.mFoundation;
+}
+
+bool Candidate::operator!=(const Candidate &other) const {
+	return mFoundation != other.mFoundation;
+}
+
+bool Candidate::isResolved() const { return mFamily != Family::Unresolved; }
+
+Candidate::Family Candidate::family() const { return mFamily; }
+
+std::optional<string> Candidate::address() const {
+	return isResolved() ? std::make_optional(mAddress) : nullopt;
+}
+
+std::optional<uint16_t> Candidate::port() const {
+	return isResolved() ? std::make_optional(mPort) : nullopt;
+}
+
 } // namespace rtc
 
 std::ostream &operator<<(std::ostream &out, const rtc::Candidate &candidate) {
 	return out << std::string(candidate);
 }
 
-std::ostream &operator<<(std::ostream &out, const rtc::CandidateType &type) {
+std::ostream &operator<<(std::ostream &out, const rtc::Candidate::Type &type) {
 	switch (type) {
-	case rtc::CandidateType::Host:
-		return out << "Host";
-	case rtc::CandidateType::PeerReflexive:
-		return out << "PeerReflexive";
-	case rtc::CandidateType::Relayed:
-		return out << "Relayed";
-	case rtc::CandidateType::ServerReflexive:
-		return out << "ServerReflexive";
+	case rtc::Candidate::Type::Host:
+		return out << "host";
+	case rtc::Candidate::Type::PeerReflexive:
+		return out << "prflx";
+	case rtc::Candidate::Type::ServerReflexive:
+		return out << "srflx";
+	case rtc::Candidate::Type::Relayed:
+		return out << "relay";
 	default:
-		return out << "Unknown";
+		return out << "unknown";
 	}
 }
 
-std::ostream &operator<<(std::ostream &out, const rtc::CandidateTransportType &transportType) {
+std::ostream &operator<<(std::ostream &out, const rtc::Candidate::TransportType &transportType) {
 	switch (transportType) {
-	case rtc::CandidateTransportType::TcpActive:
-		return out << "TcpActive";
-	case rtc::CandidateTransportType::TcpPassive:
-		return out << "TcpPassive";
-	case rtc::CandidateTransportType::TcpSo:
-		return out << "TcpSo";
-	case rtc::CandidateTransportType::Udp:
-		return out << "Udp";
+	case rtc::Candidate::TransportType::Udp:
+		return out << "UDP";
+	case rtc::Candidate::TransportType::TcpActive:
+		return out << "TCP_active";
+	case rtc::Candidate::TransportType::TcpPassive:
+		return out << "TCP_passive";
+	case rtc::Candidate::TransportType::TcpSo:
+		return out << "TCP_so";
+	case rtc::Candidate::TransportType::TcpUnknown:
+		return out << "TCP_unknown";
 	default:
-		return out << "Unknown";
+		return out << "unknown";
 	}
 }

src/capi.cpp

@@ -29,6 +29,7 @@
 
 #include "plog/Formatters/FuncMessageFormatter.h"
 
+#include <chrono>
 #include <exception>
 #include <mutex>
 #include <type_traits>
@@ -43,11 +44,13 @@
 using namespace rtc;
 using std::shared_ptr;
 using std::string;
+using std::chrono::milliseconds;
 
 namespace {
 
 std::unordered_map<int, shared_ptr<PeerConnection>> peerConnectionMap;
 std::unordered_map<int, shared_ptr<DataChannel>> dataChannelMap;
+std::unordered_map<int, shared_ptr<Track>> trackMap;
 #if RTC_ENABLE_WEBSOCKET
 std::unordered_map<int, shared_ptr<WebSocket>> webSocketMap;
 #endif
@@ -82,6 +85,14 @@ shared_ptr<DataChannel> getDataChannel(int id) {
 		throw std::invalid_argument("DataChannel ID does not exist");
 }
 
+shared_ptr<Track> getTrack(int id) {
+	std::lock_guard lock(mutex);
+	if (auto it = trackMap.find(id); it != trackMap.end())
+		return it->second;
+	else
+		throw std::invalid_argument("Track ID does not exist");
+}
+
 int emplacePeerConnection(shared_ptr<PeerConnection> ptr) {
 	std::lock_guard lock(mutex);
 	int pc = ++lastId;
@@ -98,6 +109,14 @@ int emplaceDataChannel(shared_ptr<DataChannel> ptr) {
 	return dc;
 }
 
+int emplaceTrack(shared_ptr<Track> ptr) {
+	std::lock_guard lock(mutex);
+	int tr = ++lastId;
+	trackMap.emplace(std::make_pair(tr, ptr));
+	userPointerMap.emplace(std::make_pair(tr, nullptr));
+	return tr;
+}
+
 void erasePeerConnection(int pc) {
 	std::lock_guard lock(mutex);
 	if (peerConnectionMap.erase(pc) == 0)
@@ -112,6 +131,13 @@ void eraseDataChannel(int dc) {
 	userPointerMap.erase(dc);
 }
 
+void eraseTrack(int tr) {
+	std::lock_guard lock(mutex);
+	if (trackMap.erase(tr) == 0)
+		throw std::invalid_argument("Track ID does not exist");
+	userPointerMap.erase(tr);
+}
+
 #if RTC_ENABLE_WEBSOCKET
 shared_ptr<WebSocket> getWebSocket(int id) {
 	std::lock_guard lock(mutex);
@@ -141,11 +167,13 @@ shared_ptr<Channel> getChannel(int id) {
 	std::lock_guard lock(mutex);
 	if (auto it = dataChannelMap.find(id); it != dataChannelMap.end())
 		return it->second;
+	if (auto it = trackMap.find(id); it != trackMap.end())
+		return it->second;
 #if RTC_ENABLE_WEBSOCKET
 	if (auto it = webSocketMap.find(id); it != webSocketMap.end())
 		return it->second;
 #endif
-	throw std::invalid_argument("DataChannel or WebSocket ID does not exist");
+	throw std::invalid_argument("DataChannel, Track, or WebSocket ID does not exist");
 }
 
 template <typename F> int wrap(F func) {
@@ -167,12 +195,42 @@ template <typename F> int wrap(F func) {
 		return RTC_ERR_SUCCESS;                                                                    \
 	})
 
-class plog_appender : public plog::IAppender {
-public:
-	plog_appender(rtcLogCallbackFunc cb = nullptr) { set_callback(cb); }
+int copyAndReturn(string s, char *buffer, int size) {
+	if (!buffer)
+		return int(s.size() + 1);
 
-	void set_callback(rtcLogCallbackFunc cb) {
-		std::lock_guard lock(mutex);
+	if (size < int(s.size()))
+		return RTC_ERR_TOO_SMALL;
+
+	std::copy(s.begin(), s.end(), buffer);
+	buffer[s.size()] = '\0';
+	return int(s.size() + 1);
+}
+
+int copyAndReturn(binary b, char *buffer, int size) {
+	if (!buffer)
+		return int(b.size());
+
+	if (size < int(b.size()))
+		return RTC_ERR_TOO_SMALL;
+
+	auto data = reinterpret_cast<const char *>(b.data());
+	std::copy(data, data + b.size(), buffer);
+	buffer[b.size()] = '\0';
+	return int(b.size());
+}
+
+class plogAppender : public plog::IAppender {
+public:
+	plogAppender(rtcLogCallbackFunc cb = nullptr) { setCallback(cb); }
+
+	plogAppender(plogAppender &&appender) : callback(nullptr) {
+		std::lock_guard lock(appender.callbackMutex);
+		std::swap(appender.callback, callback);
+	}
+
+	void setCallback(rtcLogCallbackFunc cb) {
+		std::lock_guard lock(callbackMutex);
 		callback = cb;
 	}
 
@@ -187,7 +245,7 @@ public:
 #else
 		std::string str = formatted;
 #endif
-		std::lock_guard lock(mutex);
+		std::lock_guard lock(callbackMutex);
 		if (callback)
 			callback(static_cast<rtcLogLevel>(record.getSeverity()), str.c_str());
 		else
@@ -196,18 +254,24 @@ public:
 
 private:
 	rtcLogCallbackFunc callback;
+	std::mutex callbackMutex;
 };
 
 } // namespace
 
 void rtcInitLogger(rtcLogLevel level, rtcLogCallbackFunc cb) {
-	static std::optional<plog_appender> appender;
-	if (appender)
-		appender->set_callback(cb);
-	else if (cb)
-		appender.emplace(plog_appender(cb));
-
-	InitLogger(static_cast<plog::Severity>(level), appender ? &appender.value() : nullptr);
+	static std::optional<plogAppender> appender;
+	const auto severity = static_cast<plog::Severity>(level);
+	std::lock_guard lock(mutex);
+	if (appender) {
+		appender->setCallback(cb);
+		InitLogger(severity, nullptr); // change the severity
+	} else if (cb) {
+		appender.emplace(plogAppender(cb));
+		InitLogger(severity, &appender.value());
+	} else {
+		InitLogger(severity, nullptr); // log to stdout
+	}
 }
 
 void rtcSetUserPointer(int i, void *ptr) { setUserPointer(i, ptr); }
@@ -240,16 +304,52 @@ int rtcDeletePeerConnection(int pc) {
 	});
 }
 
-int rtcCreateDataChannel(int pc, const char *label) {
+int rtcAddDataChannel(int pc, const char *label) { return rtcAddDataChannelEx(pc, label, nullptr); }
+
+int rtcAddDataChannelEx(int pc, const char *label, const rtcDataChannelInit *init) {
 	return WRAP({
+		DataChannelInit dci = {};
+		if (init) {
+			auto *reliability = &init->reliability;
+			dci.reliability.unordered = reliability->unordered;
+			if (reliability->unreliable) {
+				if (reliability->maxPacketLifeTime > 0) {
+					dci.reliability.type = Reliability::Type::Timed;
+					dci.reliability.rexmit = milliseconds(reliability->maxPacketLifeTime);
+				} else {
+					dci.reliability.type = Reliability::Type::Rexmit;
+					dci.reliability.rexmit = int(reliability->maxRetransmits);
+				}
+			} else {
+				dci.reliability.type = Reliability::Type::Reliable;
+			}
+
+			dci.negotiated = init->negotiated;
+			dci.id = init->manualStream ? std::make_optional(init->stream) : nullopt;
+			dci.protocol = init->protocol ? init->protocol : "";
+		}
+
 		auto peerConnection = getPeerConnection(pc);
-		int dc = emplaceDataChannel(peerConnection->createDataChannel(string(label)));
+		int dc = emplaceDataChannel(
+		    peerConnection->addDataChannel(string(label ? label : ""), std::move(dci)));
+
 		if (auto ptr = getUserPointer(pc))
 			rtcSetUserPointer(dc, *ptr);
+
 		return dc;
 	});
 }
 
+int rtcCreateDataChannel(int pc, const char *label) {
+	return rtcCreateDataChannelEx(pc, label, nullptr);
+}
+
+int rtcCreateDataChannelEx(int pc, const char *label, const rtcDataChannelInit *init) {
+	int dc = rtcAddDataChannelEx(pc, label, init);
+	rtcSetLocalDescription(pc, NULL);
+	return dc;
+}
+
 int rtcDeleteDataChannel(int dc) {
 	return WRAP({
 		auto dataChannel = getDataChannel(dc);
@@ -264,6 +364,42 @@ int rtcDeleteDataChannel(int dc) {
 	});
 }
 
+int rtcAddTrack(int pc, const char *mediaDescriptionSdp) {
+	return WRAP({
+		if (!mediaDescriptionSdp)
+			throw std::invalid_argument("Unexpected null pointer for track media description");
+
+		auto peerConnection = getPeerConnection(pc);
+		Description::Media media{string(mediaDescriptionSdp)};
+		int tr = emplaceTrack(peerConnection->addTrack(std::move(media)));
+		if (auto ptr = getUserPointer(pc))
+			rtcSetUserPointer(tr, *ptr);
+
+		return tr;
+	});
+}
+
+int rtcDeleteTrack(int tr) {
+	return WRAP({
+		auto track = getTrack(tr);
+		track->onOpen(nullptr);
+		track->onClosed(nullptr);
+		track->onError(nullptr);
+		track->onMessage(nullptr);
+		track->onBufferedAmountLow(nullptr);
+		track->onAvailable(nullptr);
+
+		eraseTrack(tr);
+	});
+}
+
+int rtcGetTrackDescription(int tr, char *buffer, int size) {
+	return WRAP({
+		auto track = getTrack(tr);
+		return copyAndReturn(track->description(), buffer, size);
+	});
+}
+
 #if RTC_ENABLE_WEBSOCKET
 int rtcCreateWebSocket(const char *url) {
 	return WRAP({
@@ -298,29 +434,13 @@ int rtcDeleteWebsocket(int ws) {
 }
 #endif
 
-int rtcSetDataChannelCallback(int pc, rtcDataChannelCallbackFunc cb) {
-	return WRAP({
-		auto peerConnection = getPeerConnection(pc);
-		if (cb)
-			peerConnection->onDataChannel([pc, cb](std::shared_ptr<DataChannel> dataChannel) {
-				int dc = emplaceDataChannel(dataChannel);
-				if (auto ptr = getUserPointer(pc)) {
-					rtcSetUserPointer(dc, *ptr);
-					cb(dc, *ptr);
-				}
-			});
-		else
-			peerConnection->onDataChannel(nullptr);
-	});
-}
-
 int rtcSetLocalDescriptionCallback(int pc, rtcDescriptionCallbackFunc cb) {
 	return WRAP({
 		auto peerConnection = getPeerConnection(pc);
 		if (cb)
-			peerConnection->onLocalDescription([pc, cb](const Description &desc) {
+			peerConnection->onLocalDescription([pc, cb](Description desc) {
 				if (auto ptr = getUserPointer(pc))
-					cb(string(desc).c_str(), desc.typeString().c_str(), *ptr);
+					cb(pc, string(desc).c_str(), desc.typeString().c_str(), *ptr);
 			});
 		else
 			peerConnection->onLocalDescription(nullptr);
@@ -331,9 +451,9 @@ int rtcSetLocalCandidateCallback(int pc, rtcCandidateCallbackFunc cb) {
 	return WRAP({
 		auto peerConnection = getPeerConnection(pc);
 		if (cb)
-			peerConnection->onLocalCandidate([pc, cb](const Candidate &cand) {
+			peerConnection->onLocalCandidate([pc, cb](Candidate cand) {
 				if (auto ptr = getUserPointer(pc))
-					cb(cand.candidate().c_str(), cand.mid().c_str(), *ptr);
+					cb(pc, cand.candidate().c_str(), cand.mid().c_str(), *ptr);
 			});
 		else
 			peerConnection->onLocalCandidate(nullptr);
@@ -346,7 +466,7 @@ int rtcSetStateChangeCallback(int pc, rtcStateChangeCallbackFunc cb) {
 		if (cb)
 			peerConnection->onStateChange([pc, cb](PeerConnection::State state) {
 				if (auto ptr = getUserPointer(pc))
-					cb(static_cast<rtcState>(state), *ptr);
+					cb(pc, static_cast<rtcState>(state), *ptr);
 			});
 		else
 			peerConnection->onStateChange(nullptr);
@@ -359,19 +479,72 @@ int rtcSetGatheringStateChangeCallback(int pc, rtcGatheringStateCallbackFunc cb)
 		if (cb)
 			peerConnection->onGatheringStateChange([pc, cb](PeerConnection::GatheringState state) {
 				if (auto ptr = getUserPointer(pc))
-					cb(static_cast<rtcGatheringState>(state), *ptr);
+					cb(pc, static_cast<rtcGatheringState>(state), *ptr);
 			});
 		else
 			peerConnection->onGatheringStateChange(nullptr);
 	});
 }
 
+int rtcSetSignalingStateChangeCallback(int pc, rtcSignalingStateCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onSignalingStateChange([pc, cb](PeerConnection::SignalingState state) {
+				if (auto ptr = getUserPointer(pc))
+					cb(pc, static_cast<rtcSignalingState>(state), *ptr);
+			});
+		else
+			peerConnection->onGatheringStateChange(nullptr);
+	});
+}
+
+int rtcSetDataChannelCallback(int pc, rtcDataChannelCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onDataChannel([pc, cb](std::shared_ptr<DataChannel> dataChannel) {
+				int dc = emplaceDataChannel(dataChannel);
+				if (auto ptr = getUserPointer(pc)) {
+					rtcSetUserPointer(dc, *ptr);
+					cb(pc, dc, *ptr);
+				}
+			});
+		else
+			peerConnection->onDataChannel(nullptr);
+	});
+}
+
+int rtcSetTrackCallback(int pc, rtcTrackCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onTrack([pc, cb](std::shared_ptr<Track> track) {
+				int tr = emplaceTrack(track);
+				if (auto ptr = getUserPointer(pc)) {
+					rtcSetUserPointer(tr, *ptr);
+					cb(pc, tr, *ptr);
+				}
+			});
+		else
+			peerConnection->onTrack(nullptr);
+	});
+}
+
+int rtcSetLocalDescription(int pc, const char *type) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		peerConnection->setLocalDescription(type ? Description::stringToType(type)
+		                                         : Description::Type::Unspec);
+	});
+}
+
 int rtcSetRemoteDescription(int pc, const char *sdp, const char *type) {
 	return WRAP({
 		auto peerConnection = getPeerConnection(pc);
 
 		if (!sdp)
-			throw std::invalid_argument("Unexpected null pointer");
+			throw std::invalid_argument("Unexpected null pointer for remote description");
 
 		peerConnection->setRemoteDescription({string(sdp), type ? string(type) : ""});
 	});
@@ -382,29 +555,42 @@ int rtcAddRemoteCandidate(int pc, const char *cand, const char *mid) {
 		auto peerConnection = getPeerConnection(pc);
 
 		if (!cand)
-			throw std::invalid_argument("Unexpected null pointer");
+			throw std::invalid_argument("Unexpected null pointer for remote candidate");
 
 		peerConnection->addRemoteCandidate({string(cand), mid ? string(mid) : ""});
 	});
 }
 
+int rtcGetLocalDescription(int pc, char *buffer, int size) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+
+		if (auto desc = peerConnection->localDescription())
+			return copyAndReturn(string(*desc), buffer, size);
+		else
+			return RTC_ERR_NOT_AVAIL;
+	});
+}
+
+int rtcGetRemoteDescription(int pc, char *buffer, int size) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+
+		if (auto desc = peerConnection->remoteDescription())
+			return copyAndReturn(string(*desc), buffer, size);
+		else
+			return RTC_ERR_NOT_AVAIL;
+	});
+}
+
 int rtcGetLocalAddress(int pc, char *buffer, int size) {
 	return WRAP({
 		auto peerConnection = getPeerConnection(pc);
 
-		if (!buffer)
-			throw std::invalid_argument("Unexpected null pointer");
-
-		if (size <= 0)
-			return 0;
-
-		if (auto addr = peerConnection->localAddress()) {
-			const char *data = addr->data();
-			size = std::min(size - 1, int(addr->size()));
-			std::copy(data, data + size, buffer);
-			buffer[size] = '\0';
-			return size + 1;
-		}
+		if (auto addr = peerConnection->localAddress())
+			return copyAndReturn(std::move(*addr), buffer, size);
+		else
+			return RTC_ERR_NOT_AVAIL;
 	});
 }
 
@@ -412,38 +598,75 @@ int rtcGetRemoteAddress(int pc, char *buffer, int size) {
 	return WRAP({
 		auto peerConnection = getPeerConnection(pc);
 
-		if (!buffer)
-			throw std::invalid_argument("Unexpected null pointer");
+		if (auto addr = peerConnection->remoteAddress())
+			return copyAndReturn(std::move(*addr), buffer, size);
+		else
+			return RTC_ERR_NOT_AVAIL;
+	});
+}
 
-		if (size <= 0)
-			return 0;
+int rtcGetSelectedCandidatePair(int pc, char *local, int localSize, char *remote, int remoteSize) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
 
-		if (auto addr = peerConnection->remoteAddress()) {
-			const char *data = addr->data();
-			size = std::min(size - 1, int(addr->size()));
-			std::copy(data, data + size, buffer);
-			buffer[size] = '\0';
-			return int(size + 1);
-		}
+		Candidate localCand;
+		Candidate remoteCand;
+		if (!peerConnection->getSelectedCandidatePair(&localCand, &remoteCand))
+			return RTC_ERR_NOT_AVAIL;
+
+		int localRet = copyAndReturn(string(localCand), local, localSize);
+		if (localRet < 0)
+			return localRet;
+
+		int remoteRet = copyAndReturn(string(remoteCand), remote, remoteSize);
+		if (remoteRet < 0)
+			return remoteRet;
+
+		return std::max(localRet, remoteRet);
+	});
+}
+
+int rtcGetDataChannelStream(int dc) {
+	return WRAP({
+		auto dataChannel = getDataChannel(dc);
+		return int(dataChannel->id());
 	});
 }
 
 int rtcGetDataChannelLabel(int dc, char *buffer, int size) {
 	return WRAP({
 		auto dataChannel = getDataChannel(dc);
+		return copyAndReturn(dataChannel->label(), buffer, size);
+	});
+}
 
-		if (!buffer)
-			throw std::invalid_argument("Unexpected null pointer");
+int rtcGetDataChannelProtocol(int dc, char *buffer, int size) {
+	return WRAP({
+		auto dataChannel = getDataChannel(dc);
+		return copyAndReturn(dataChannel->protocol(), buffer, size);
+	});
+}
 
-		if (size <= 0)
-			return 0;
+int rtcGetDataChannelReliability(int dc, rtcReliability *reliability) {
+	return WRAP({
+		auto dataChannel = getDataChannel(dc);
 
-		string label = dataChannel->label();
-		const char *data = label.data();
-		size = std::min(size - 1, int(label.size()));
-		std::copy(data, data + size, buffer);
-		buffer[size] = '\0';
-		return int(size + 1);
+		if (!reliability)
+			throw std::invalid_argument("Unexpected null pointer for reliability");
+
+		Reliability dcr = dataChannel->reliability();
+		std::memset(reliability, 0, sizeof(*reliability));
+		reliability->unordered = dcr.unordered;
+		if (dcr.type == Reliability::Type::Timed) {
+			reliability->unreliable = true;
+			reliability->maxPacketLifeTime = unsigned(std::get<milliseconds>(dcr.rexmit).count());
+		} else if (dcr.type == Reliability::Type::Rexmit) {
+			reliability->unreliable = true;
+			reliability->maxRetransmits = unsigned(std::get<int>(dcr.rexmit));
+		} else {
+			reliability->unreliable = false;
+		}
+		return RTC_ERR_SUCCESS;
 	});
 }
 
@@ -453,7 +676,7 @@ int rtcSetOpenCallback(int id, rtcOpenCallbackFunc cb) {
 		if (cb)
 			channel->onOpen([id, cb]() {
 				if (auto ptr = getUserPointer(id))
-					cb(*ptr);
+					cb(id, *ptr);
 			});
 		else
 			channel->onOpen(nullptr);
@@ -466,7 +689,7 @@ int rtcSetClosedCallback(int id, rtcClosedCallbackFunc cb) {
 		if (cb)
 			channel->onClosed([id, cb]() {
 				if (auto ptr = getUserPointer(id))
-					cb(*ptr);
+					cb(id, *ptr);
 			});
 		else
 			channel->onClosed(nullptr);
@@ -477,9 +700,9 @@ int rtcSetErrorCallback(int id, rtcErrorCallbackFunc cb) {
 	return WRAP({
 		auto channel = getChannel(id);
 		if (cb)
-			channel->onError([id, cb](const string &error) {
+			channel->onError([id, cb](string error) {
 				if (auto ptr = getUserPointer(id))
-					cb(error.c_str(), *ptr);
+					cb(id, error.c_str(), *ptr);
 			});
 		else
 			channel->onError(nullptr);
@@ -491,13 +714,13 @@ int rtcSetMessageCallback(int id, rtcMessageCallbackFunc cb) {
 		auto channel = getChannel(id);
 		if (cb)
 			channel->onMessage(
-			    [id, cb](const binary &b) {
+			    [id, cb](binary b) {
 				    if (auto ptr = getUserPointer(id))
-					    cb(reinterpret_cast<const char *>(b.data()), int(b.size()), *ptr);
+					    cb(id, reinterpret_cast<const char *>(b.data()), int(b.size()), *ptr);
 			    },
-			    [id, cb](const string &s) {
+			    [id, cb](string s) {
 				    if (auto ptr = getUserPointer(id))
-					    cb(s.c_str(), -int(s.size() + 1), *ptr);
+					    cb(id, s.c_str(), -int(s.size() + 1), *ptr);
 			    });
 		else
 			channel->onMessage(nullptr);
@@ -508,8 +731,8 @@ int rtcSendMessage(int id, const char *data, int size) {
 	return WRAP({
 		auto channel = getChannel(id);
 
-		if (!data)
-			throw std::invalid_argument("Unexpected null pointer");
+		if (!data && size != 0)
+			throw std::invalid_argument("Unexpected null pointer for data");
 
 		if (size >= 0) {
 			auto b = reinterpret_cast<const byte *>(data);
@@ -544,7 +767,7 @@ int rtcSetBufferedAmountLowCallback(int id, rtcBufferedAmountLowCallbackFunc cb)
 		if (cb)
 			channel->onBufferedAmountLow([id, cb]() {
 				if (auto ptr = getUserPointer(id))
-					cb(*ptr);
+					cb(id, *ptr);
 			});
 		else
 			channel->onBufferedAmountLow(nullptr);
@@ -559,12 +782,12 @@ int rtcSetAvailableCallback(int id, rtcAvailableCallbackFunc cb) {
 	return WRAP({
 		auto channel = getChannel(id);
 		if (cb)
-			channel->onOpen([id, cb]() {
+			channel->onAvailable([id, cb]() {
 				if (auto ptr = getUserPointer(id))
-					cb(*ptr);
+					cb(id, *ptr);
 			});
 		else
-			channel->onOpen(nullptr);
+			channel->onAvailable(nullptr);
 	});
 }
 
@@ -572,30 +795,41 @@ int rtcReceiveMessage(int id, char *buffer, int *size) {
 	return WRAP({
 		auto channel = getChannel(id);
 
-		if (!buffer || !size)
-			throw std::invalid_argument("Unexpected null pointer");
+		if (!size)
+			throw std::invalid_argument("Unexpected null pointer for size");
+
+		*size = std::abs(*size);
+
+		auto message = channel->peek();
+		if (!message)
+			return RTC_ERR_NOT_AVAIL;
 
-		if (auto message = channel->receive())
 		return std::visit( //
-			    overloaded{    //
-			               [&](const binary &b) {
-				               *size = std::min(*size, int(b.size()));
-				               auto data = reinterpret_cast<const char *>(b.data());
-				               std::copy(data, data + *size, buffer);
-				               return 1;
-			               },
-			               [&](const string &s) {
-				               int len = std::min(*size - 1, int(s.size()));
-				               if (len >= 0) {
-					               std::copy(s.data(), s.data() + len, buffer);
-					               buffer[len] = '\0';
+		    overloaded{
+		        [&](binary b) {
+			        int ret = copyAndReturn(std::move(b), buffer, *size);
+			        if (ret >= 0) {
+				        channel->receive(); // discard
+				        *size = ret;
+				        return RTC_ERR_SUCCESS;
+			        } else {
+				        *size = int(b.size());
+				        return ret;
 			        }
-				               *size = -(len + 1);
-				               return 1;
-			               }},
+		        },
+		        [&](string s) {
+			        int ret = copyAndReturn(std::move(s), buffer, *size);
+			        if (ret >= 0) {
+				        channel->receive(); // discard
+				        *size = -ret;
+				        return RTC_ERR_SUCCESS;
+			        } else {
+				        *size = -int(s.size() + 1);
+				        return ret;
+			        }
+		        },
+		    },
 		    *message);
-		else
-			return 0;
 	});
 }
 

src/certificate.cpp

@@ -99,7 +99,11 @@ certificate_ptr make_certificate_impl(string commonName) {
 	unique_ptr<gnutls_x509_crt_t, decltype(&free_crt)> crt(new_crt(), free_crt);
 	unique_ptr<gnutls_x509_privkey_t, decltype(&free_privkey)> privkey(new_privkey(), free_privkey);
 
+#ifdef RSA_KEY_BITS_2048
+	const unsigned int bits = 2048;
+#else
 	const unsigned int bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_HIGH);
+#endif
 	gnutls::check(gnutls_x509_privkey_generate(*privkey, GNUTLS_PK_RSA, bits, 0),
 	              "Unable to generate key pair");
 
@@ -149,15 +153,16 @@ Certificate::Certificate(string crt_pem, string key_pem) {
 	mFingerprint = make_fingerprint(mX509.get());
 }
 
-Certificate::Certificate(shared_ptr<X509> x509, shared_ptr<EVP_PKEY> pkey) :
-	mX509(std::move(x509)), mPKey(std::move(pkey))
-{
+Certificate::Certificate(shared_ptr<X509> x509, shared_ptr<EVP_PKEY> pkey)
+    : mX509(std::move(x509)), mPKey(std::move(pkey)) {
 	mFingerprint = make_fingerprint(mX509.get());
 }
 
 string Certificate::fingerprint() const { return mFingerprint; }
 
-std::tuple<X509 *, EVP_PKEY *> Certificate::credentials() const { return {mX509.get(), mPKey.get()}; }
+std::tuple<X509 *, EVP_PKEY *> Certificate::credentials() const {
+	return {mX509.get(), mPKey.get()};
+}
 
 string make_fingerprint(X509 *x509) {
 	const size_t size = 32;
@@ -190,7 +195,11 @@ certificate_ptr make_certificate_impl(string commonName) {
 	if (!x509 || !pkey || !rsa || !exponent || !serial_number || !name)
 		throw std::runtime_error("Unable allocate structures for certificate generation");
 
-	const int bits = 4096;
+#ifdef RSA_KEY_BITS_2048
+	const int bits = 2048;
+#else
+	const int bits = 3072;
+#endif
 	const unsigned int e = 65537; // 2^16 + 1
 
 	if (!pkey || !rsa || !exponent || !BN_set_word(exponent.get(), e) ||

src/channel.cpp

@@ -26,19 +26,13 @@ size_t Channel::bufferedAmount() const { return mBufferedAmount; }
 
 size_t Channel::availableAmount() const { return 0; }
 
-void Channel::onOpen(std::function<void()> callback) {
-	mOpenCallback = callback;
-}
+void Channel::onOpen(std::function<void()> callback) { mOpenCallback = callback; }
 
-void Channel::onClosed(std::function<void()> callback) {
-	mClosedCallback = callback;
-}
+void Channel::onClosed(std::function<void()> callback) { mClosedCallback = callback; }
 
-void Channel::onError(std::function<void(const string &error)> callback) {
-	mErrorCallback = callback;
-}
+void Channel::onError(std::function<void(string error)> callback) { mErrorCallback = callback; }
 
-void Channel::onMessage(std::function<void(const std::variant<binary, string> &data)> callback) {
+void Channel::onMessage(std::function<void(message_variant data)> callback) {
 	mMessageCallback = callback;
 
 	// Pass pending messages
@@ -46,10 +40,10 @@ void Channel::onMessage(std::function<void(const std::variant<binary, string> &d
 		mMessageCallback(*message);
 }
 
-void Channel::onMessage(std::function<void(const binary &data)> binaryCallback,
-                        std::function<void(const string &data)> stringCallback) {
-	onMessage([binaryCallback, stringCallback](const std::variant<binary, string> &data) {
-		std::visit(overloaded{binaryCallback, stringCallback}, data);
+void Channel::onMessage(std::function<void(binary data)> binaryCallback,
+                        std::function<void(string data)> stringCallback) {
+	onMessage([binaryCallback, stringCallback](std::variant<binary, string> data) {
+		std::visit(overloaded{binaryCallback, stringCallback}, std::move(data));
 	});
 }
 
@@ -59,15 +53,13 @@ void Channel::onBufferedAmountLow(std::function<void()> callback) {
 
 void Channel::setBufferedAmountLowThreshold(size_t amount) { mBufferedAmountLowThreshold = amount; }
 
-void Channel::onAvailable(std::function<void()> callback) {
-	mAvailableCallback = callback;
-}
+void Channel::onAvailable(std::function<void()> callback) { mAvailableCallback = callback; }
 
 void Channel::triggerOpen() { mOpenCallback(); }
 
 void Channel::triggerClosed() { mClosedCallback(); }
 
-void Channel::triggerError(const string &error) { mErrorCallback(error); }
+void Channel::triggerError(string error) { mErrorCallback(error); }
 
 void Channel::triggerAvailable(size_t count) {
 	if (count == 1)
@@ -98,4 +90,3 @@ void Channel::resetCallbacks() {
 }
 
 } // namespace rtc
-

src/datachannel.cpp

@@ -31,6 +31,7 @@ namespace rtc {
 
 using std::shared_ptr;
 using std::weak_ptr;
+using std::chrono::milliseconds;
 
 // Messages for the DataChannel establishment protocol
 // See https://tools.ietf.org/html/draft-ietf-rtcweb-data-protocol-09
@@ -43,6 +44,12 @@ enum MessageType : uint8_t {
 	MESSAGE_CLOSE = 0x04
 };
 
+enum ChannelType : uint8_t {
+	CHANNEL_RELIABLE = 0x00,
+	CHANNEL_PARTIAL_RELIABLE_REXMIT = 0x01,
+	CHANNEL_PARTIAL_RELIABLE_TIMED = 0x02
+};
+
 #pragma pack(push, 1)
 struct OpenMessage {
 	uint8_t type = MESSAGE_OPEN;
@@ -65,26 +72,18 @@ struct CloseMessage {
 };
 #pragma pack(pop)
 
-const size_t RECV_QUEUE_LIMIT = 1024 * 1024; // 1 MiB
-
-DataChannel::DataChannel(weak_ptr<PeerConnection> pc, unsigned int stream, string label,
+DataChannel::DataChannel(weak_ptr<PeerConnection> pc, uint16_t stream, string label,
                          string protocol, Reliability reliability)
     : mPeerConnection(pc), mStream(stream), mLabel(std::move(label)),
       mProtocol(std::move(protocol)),
       mReliability(std::make_shared<Reliability>(std::move(reliability))),
       mRecvQueue(RECV_QUEUE_LIMIT, message_size_func) {}
 
-DataChannel::DataChannel(weak_ptr<PeerConnection> pc, weak_ptr<SctpTransport> transport,
-                         unsigned int stream)
-    : mPeerConnection(pc), mSctpTransport(transport), mStream(stream),
-      mReliability(std::make_shared<Reliability>()),
-      mRecvQueue(RECV_QUEUE_LIMIT, message_size_func) {}
+DataChannel::~DataChannel() { close(); }
 
-DataChannel::~DataChannel() {
-	close();
-}
+uint16_t DataChannel::stream() const { return mStream; }
 
-unsigned int DataChannel::stream() const { return mStream; }
+uint16_t DataChannel::id() const { return uint16_t(mStream); }
 
 string DataChannel::label() const { return mLabel; }
 
@@ -110,40 +109,37 @@ void DataChannel::remoteClose() {
 	mSctpTransport.reset();
 }
 
-bool DataChannel::send(const std::variant<binary, string> &data) {
-	return std::visit(
-	    [&](const auto &d) {
-		    using T = std::decay_t<decltype(d)>;
-		    constexpr auto type = std::is_same_v<T, string> ? Message::String : Message::Binary;
-		    auto *b = reinterpret_cast<const byte *>(d.data());
-		    return outgoing(std::make_shared<Message>(b, b + d.size(), type));
-	    },
-	    data);
-}
+bool DataChannel::send(message_variant data) { return outgoing(make_message(std::move(data))); }
 
 bool DataChannel::send(const byte *data, size_t size) {
 	return outgoing(std::make_shared<Message>(data, data + size, Message::Binary));
 }
 
-std::optional<std::variant<binary, string>> DataChannel::receive() {
-	while (!mRecvQueue.empty()) {
-		auto message = *mRecvQueue.pop();
-		switch (message->type) {
-		case Message::Control: {
+std::optional<message_variant> DataChannel::receive() {
+	while (auto next = mRecvQueue.tryPop()) {
+		message_ptr message = *next;
+		if (message->type != Message::Control)
+			return to_variant(std::move(*message));
+
 		auto raw = reinterpret_cast<const uint8_t *>(message->data());
-			if (raw[0] == MESSAGE_CLOSE)
+		if (!message->empty() && raw[0] == MESSAGE_CLOSE)
 			remoteClose();
-			break;
-		}
-		case Message::String:
-			return std::make_optional(
-			    string(reinterpret_cast<const char *>(message->data()), message->size()));
-		case Message::Binary:
-			return std::make_optional(std::move(*message));
-		default:
-			// Ignore
-			break;
 	}
+
+	return nullopt;
+}
+
+std::optional<message_variant> DataChannel::peek() {
+	while (auto next = mRecvQueue.peek()) {
+		message_ptr message = *next;
+		if (message->type != Message::Control)
+			return to_variant(std::move(*message));
+
+		auto raw = reinterpret_cast<const uint8_t *>(message->data());
+		if (!message->empty() && raw[0] == MESSAGE_CLOSE)
+			remoteClose();
+
+		mRecvQueue.tryPop();
 	}
 
 	return nullopt;
@@ -157,7 +153,8 @@ size_t DataChannel::maxMessageSize() const {
 	size_t remoteMax = DEFAULT_MAX_MESSAGE_SIZE;
 	if (auto pc = mPeerConnection.lock())
 		if (auto description = pc->remoteDescription())
-			if (auto maxMessageSize = description->maxMessageSize())
+			if (auto *application = description->application())
+				if (auto maxMessageSize = application->maxMessageSize())
 					remoteMax = *maxMessageSize > 0 ? *maxMessageSize : LOCAL_MAX_MESSAGE_SIZE;
 
 	return std::min(remoteMax, LOCAL_MAX_MESSAGE_SIZE);
@@ -168,32 +165,12 @@ size_t DataChannel::availableAmount() const { return mRecvQueue.amount(); }
 void DataChannel::open(shared_ptr<SctpTransport> transport) {
 	mSctpTransport = transport;
 
-	uint8_t channelType = static_cast<uint8_t>(mReliability->type);
-	if (mReliability->unordered)
-		channelType &= 0x80;
+	if (!mIsOpen.exchange(true))
+		triggerOpen();
+}
 
-	using std::chrono::milliseconds;
-	uint32_t reliabilityParameter = 0;
-	if (mReliability->type == Reliability::TYPE_PARTIAL_RELIABLE_REXMIT)
-		reliabilityParameter = uint32_t(std::get<int>(mReliability->rexmit));
-	else if (mReliability->type == Reliability::TYPE_PARTIAL_RELIABLE_TIMED)
-		reliabilityParameter = uint32_t(std::get<milliseconds>(mReliability->rexmit).count());
-
-	const size_t len = sizeof(OpenMessage) + mLabel.size() + mProtocol.size();
-	binary buffer(len, byte(0));
-	auto &open = *reinterpret_cast<OpenMessage *>(buffer.data());
-	open.type = MESSAGE_OPEN;
-	open.channelType = mReliability->type;
-	open.priority = htons(0);
-	open.reliabilityParameter = htonl(reliabilityParameter);
-	open.labelLength = htons(uint16_t(mLabel.size()));
-	open.protocolLength = htons(uint16_t(mProtocol.size()));
-
-	auto end = reinterpret_cast<char *>(buffer.data() + sizeof(OpenMessage));
-	std::copy(mLabel.begin(), mLabel.end(), end);
-	std::copy(mProtocol.begin(), mProtocol.end(), end + mLabel.size());
-
-	transport->send(make_message(buffer.begin(), buffer.end(), Message::Control, mStream));
+void DataChannel::processOpenMessage(message_ptr) {
+	PLOG_WARNING << "Received an open message for a user-negotiated DataChannel, ignoring";
 }
 
 bool DataChannel::outgoing(message_ptr message) {
@@ -205,7 +182,7 @@ bool DataChannel::outgoing(message_ptr message) {
 
 	auto transport = mSctpTransport.lock();
 	if (!transport)
-		throw std::runtime_error("DataChannel has no transport");
+		throw std::runtime_error("DataChannel transport is not open");
 
 	// Before the ACK has been received on a DataChannel, all messages must be sent ordered
 	message->reliability = mIsOpen ? mReliability : nullptr;
@@ -219,6 +196,8 @@ void DataChannel::incoming(message_ptr message) {
 
 	switch (message->type) {
 	case Message::Control: {
+		if (message->size() == 0)
+			break; // Ignore
 		auto raw = reinterpret_cast<const uint8_t *>(message->data());
 		switch (raw[0]) {
 		case MESSAGE_OPEN:
@@ -251,7 +230,62 @@ void DataChannel::incoming(message_ptr message) {
 	}
 }
 
-void DataChannel::processOpenMessage(message_ptr message) {
+NegociatedDataChannel::NegociatedDataChannel(std::weak_ptr<PeerConnection> pc, uint16_t stream,
+                                             string label, string protocol, Reliability reliability)
+    : DataChannel(pc, stream, std::move(label), std::move(protocol), std::move(reliability)) {}
+
+NegociatedDataChannel::NegociatedDataChannel(std::weak_ptr<PeerConnection> pc,
+                                             std::weak_ptr<SctpTransport> transport,
+                                             uint16_t stream)
+    : DataChannel(pc, stream, "", "", {}) {
+	mSctpTransport = transport;
+}
+
+NegociatedDataChannel::~NegociatedDataChannel() {}
+
+void NegociatedDataChannel::open(shared_ptr<SctpTransport> transport) {
+	mSctpTransport = transport;
+
+	uint8_t channelType;
+	uint32_t reliabilityParameter;
+	switch (mReliability->type) {
+	case Reliability::Type::Rexmit:
+		channelType = CHANNEL_PARTIAL_RELIABLE_REXMIT;
+		reliabilityParameter = uint32_t(std::get<int>(mReliability->rexmit));
+		break;
+
+	case Reliability::Type::Timed:
+		channelType = CHANNEL_PARTIAL_RELIABLE_TIMED;
+		reliabilityParameter = uint32_t(std::get<milliseconds>(mReliability->rexmit).count());
+		break;
+
+	default:
+		channelType = CHANNEL_RELIABLE;
+		reliabilityParameter = 0;
+		break;
+	}
+
+	if (mReliability->unordered)
+		channelType |= 0x80;
+
+	const size_t len = sizeof(OpenMessage) + mLabel.size() + mProtocol.size();
+	binary buffer(len, byte(0));
+	auto &open = *reinterpret_cast<OpenMessage *>(buffer.data());
+	open.type = MESSAGE_OPEN;
+	open.channelType = channelType;
+	open.priority = htons(0);
+	open.reliabilityParameter = htonl(reliabilityParameter);
+	open.labelLength = htons(uint16_t(mLabel.size()));
+	open.protocolLength = htons(uint16_t(mProtocol.size()));
+
+	auto end = reinterpret_cast<char *>(buffer.data() + sizeof(OpenMessage));
+	std::copy(mLabel.begin(), mLabel.end(), end);
+	std::copy(mProtocol.begin(), mProtocol.end(), end + mLabel.size());
+
+	transport->send(make_message(buffer.begin(), buffer.end(), Message::Control, mStream));
+}
+
+void NegociatedDataChannel::processOpenMessage(message_ptr message) {
 	auto transport = mSctpTransport.lock();
 	if (!transport)
 		throw std::runtime_error("DataChannel has no transport");
@@ -272,19 +306,18 @@ void DataChannel::processOpenMessage(message_ptr message) {
 	mLabel.assign(end, open.labelLength);
 	mProtocol.assign(end + open.labelLength, open.protocolLength);
 
-	using std::chrono::milliseconds;
-	mReliability->unordered = (open.reliabilityParameter & 0x80) != 0;
+	mReliability->unordered = (open.channelType & 0x80) != 0;
 	switch (open.channelType & 0x7F) {
-	case Reliability::TYPE_PARTIAL_RELIABLE_REXMIT:
-		mReliability->type = Reliability::TYPE_PARTIAL_RELIABLE_REXMIT;
+	case CHANNEL_PARTIAL_RELIABLE_REXMIT:
+		mReliability->type = Reliability::Type::Rexmit;
 		mReliability->rexmit = int(open.reliabilityParameter);
 		break;
-	case Reliability::TYPE_PARTIAL_RELIABLE_TIMED:
-		mReliability->type = Reliability::TYPE_PARTIAL_RELIABLE_TIMED;
+	case CHANNEL_PARTIAL_RELIABLE_TIMED:
+		mReliability->type = Reliability::Type::Timed;
 		mReliability->rexmit = milliseconds(open.reliabilityParameter);
 		break;
 	default:
-		mReliability->type = Reliability::TYPE_RELIABLE;
+		mReliability->type = Reliability::Type::Reliable;
 		mReliability->rexmit = int(0);
 	}
 
@@ -294,7 +327,7 @@ void DataChannel::processOpenMessage(message_ptr message) {
 
 	transport->send(make_message(buffer.begin(), buffer.end(), Message::Control, mStream));
 
-	mIsOpen = true;
+	if (!mIsOpen.exchange(true))
 		triggerOpen();
 }
 

src/dtlssrtptransport.cpp

@@ -45,6 +45,18 @@ DtlsSrtpTransport::DtlsSrtpTransport(std::shared_ptr<IceTransport> lower,
 
 	PLOG_DEBUG << "Initializing DTLS-SRTP transport";
 
+#if USE_GNUTLS
+	PLOG_DEBUG << "Setting SRTP profile (GnuTLS)";
+	gnutls::check(gnutls_srtp_set_profile(mSession, GNUTLS_SRTP_AES128_CM_HMAC_SHA1_80),
+	              "Failed to set SRTP profile");
+#else
+	PLOG_DEBUG << "Setting SRTP profile (OpenSSL)";
+	// returns 0 on success, 1 on error
+	if (SSL_set_tlsext_use_srtp(mSsl, "SRTP_AES128_CM_SHA1_80"))
+		throw std::runtime_error("Failed to set SRTP profile: " +
+		                         openssl::error_string(ERR_get_error()));
+#endif
+
 	if (srtp_err_status_t err = srtp_create(&mSrtpIn, nullptr)) {
 		throw std::runtime_error("SRTP create failed, status=" + to_string(static_cast<int>(err)));
 	}
@@ -55,7 +67,7 @@ DtlsSrtpTransport::DtlsSrtpTransport(std::shared_ptr<IceTransport> lower,
 }
 
 DtlsSrtpTransport::~DtlsSrtpTransport() {
-	stop();
+	stop(); // stop before deallocating
 
 	srtp_dealloc(mSrtpIn);
 	srtp_dealloc(mSrtpOut);
@@ -70,11 +82,12 @@ bool DtlsSrtpTransport::sendMedia(message_ptr message) {
 		return false;
 	}
 
-	int size = message->size();
+	int size = int(message->size());
 	PLOG_VERBOSE << "Send size=" << size;
 
 	// The RTP header has a minimum size of 12 bytes
-	if (size < 12)
+	// An RTCP packet can have a minimum size of 8 bytes
+	if (size < 8)
 		throw std::runtime_error("RTP/RTCP packet too short");
 
 	// srtp_protect() and srtp_protect_rtcp() assume that they can write SRTP_MAX_TRAILER_LEN (for
@@ -86,6 +99,7 @@ bool DtlsSrtpTransport::sendMedia(message_ptr message) {
 	             << unsigned(value2);
 
 	// RFC 5761 Multiplexing RTP and RTCP 4. Distinguishable RTP and RTCP Packets
+	// https://tools.ietf.org/html/rfc5761#section-4
 	// It is RECOMMENDED to follow the guidelines in the RTP/AVP profile for the choice of RTP
 	// payload type values, with the additional restriction that payload type values in the
 	// range 64-95 MUST NOT be used. Specifically, dynamic RTP payload types SHOULD be chosen in
@@ -95,16 +109,31 @@ bool DtlsSrtpTransport::sendMedia(message_ptr message) {
 		if (srtp_err_status_t err = srtp_protect_rtcp(mSrtpOut, message->data(), &size)) {
 			if (err == srtp_err_status_replay_fail)
 				throw std::runtime_error("SRTCP packet is a replay");
-			else
+			else if (err == srtp_err_status_no_ctx) {
+				auto ssrc = ((RTCP_SR *)message->data())->senderSSRC();
+				PLOG_INFO << "Adding SSRC to SRTCP: " << ssrc;
+				addSSRC(ssrc);
+				if ((err = srtp_protect_rtcp(mSrtpOut, message->data(), &size)))
 					throw std::runtime_error("SRTCP protect error, status=" +
 					                         to_string(static_cast<int>(err)));
+			} else {
+				throw std::runtime_error("SRTCP protect error, status=" +
+				                         to_string(static_cast<int>(err)));
+			}
 		}
 		PLOG_VERBOSE << "Protected SRTCP packet, size=" << size;
 	} else {
 		if (srtp_err_status_t err = srtp_protect(mSrtpOut, message->data(), &size)) {
 			if (err == srtp_err_status_replay_fail)
-				throw std::runtime_error("SRTP packet is a replay");
-			else
+				throw std::runtime_error("Outgoing SRTP packet is a replay");
+			else if (err == srtp_err_status_no_ctx) {
+				auto ssrc = ((RTP *)message->data())->ssrc();
+				PLOG_INFO << "Adding SSRC to RTP: " << ssrc;
+				addSSRC(ssrc);
+				if ((err = srtp_protect_rtcp(mSrtpOut, message->data(), &size)))
+					throw std::runtime_error("SRTCP protect error, status=" +
+					                         to_string(static_cast<int>(err)));
+			} else
 				throw std::runtime_error("SRTP protect error, status=" +
 				                         to_string(static_cast<int>(err)));
 		}
@@ -112,8 +141,7 @@ bool DtlsSrtpTransport::sendMedia(message_ptr message) {
 	}
 
 	message->resize(size);
-	outgoing(message);
-	return true;
+	return outgoing(message);
 }
 
 void DtlsSrtpTransport::incoming(message_ptr message) {
@@ -123,11 +151,12 @@ void DtlsSrtpTransport::incoming(message_ptr message) {
 		return;
 	}
 
-	int size = message->size();
+	int size = int(message->size());
 	if (size == 0)
 		return;
 
 	// RFC 5764 5.1.2. Reception
+	// https://tools.ietf.org/html/rfc5764#section-5.1.2
 	// The process for demultiplexing a packet is as follows. The receiver looks at the first byte
 	// of the packet. [...] If the value is in between 128 and 191 (inclusive), then the packet is
 	// RTP (or RTCP [...]). If the value is between 20 and 63 (inclusive), the packet is DTLS.
@@ -141,7 +170,8 @@ void DtlsSrtpTransport::incoming(message_ptr message) {
 
 	} else if (value1 >= 128 && value1 <= 191) {
 		// The RTP header has a minimum size of 12 bytes
-		if (size < 12) {
+		// An RTCP packet can have a minimum size of 8 bytes
+		if (size < 8) {
 			PLOG_WARNING << "Incoming SRTP/SRTCP packet too short, size=" << size;
 			return;
 		}
@@ -156,21 +186,48 @@ void DtlsSrtpTransport::incoming(message_ptr message) {
 			if (srtp_err_status_t err = srtp_unprotect_rtcp(mSrtpIn, message->data(), &size)) {
 				if (err == srtp_err_status_replay_fail)
 					PLOG_WARNING << "Incoming SRTCP packet is a replay";
-				else
-					PLOG_WARNING << "SRTCP unprotect error, status=" << err;
+				else if (err == srtp_err_status_auth_fail)
+					PLOG_WARNING << "Incoming SRTCP packet failed authentication check";
+				else if (err == srtp_err_status_no_ctx) {
+					auto ssrc = ((RTCP_SR *)message->data())->senderSSRC();
+					PLOG_INFO << "Adding SSRC to RTCP: " << ssrc;
+					addSSRC(ssrc);
+					if ((err = srtp_unprotect_rtcp(mSrtpIn, message->data(), &size)))
+						throw std::runtime_error("SRTCP unprotect error, status=" +
+						                         to_string(static_cast<int>(err)));
+				} else {
+					PLOG_WARNING << "SRTCP unprotect error, status=" << err
+					             << " SSRC=" << ((RTCP_SR *)message->data())->senderSSRC();
+				}
 				return;
 			}
 			PLOG_VERBOSE << "Unprotected SRTCP packet, size=" << size;
+			message->type = Message::Type::Control;
+			auto rtp = (RTCP_SR *)message->data();
+			message->stream = rtp->senderSSRC();
 		} else {
 			PLOG_VERBOSE << "Incoming SRTP packet, size=" << size;
 			if (srtp_err_status_t err = srtp_unprotect(mSrtpIn, message->data(), &size)) {
 				if (err == srtp_err_status_replay_fail)
 					PLOG_WARNING << "Incoming SRTP packet is a replay";
-				else
-					PLOG_WARNING << "SRTP unprotect error, status=" << err;
+				else if (err == srtp_err_status_auth_fail)
+					PLOG_WARNING << "Incoming SRTP packet failed authentication check";
+				else if (err == srtp_err_status_no_ctx) {
+					auto ssrc = ((RTP *)message->data())->ssrc();
+					PLOG_INFO << "Adding SSRC to RTP: " << ssrc;
+					addSSRC(ssrc);
+					if ((err = srtp_unprotect(mSrtpIn, message->data(), &size)))
+						throw std::runtime_error("SRTCP unprotect error, status=" +
+						                         to_string(static_cast<int>(err)));
+				} else
+					PLOG_WARNING << "SRTP unprotect error, status=" << err
+					             << " SSRC=" << ((RTP *)message->data())->ssrc();
 				return;
 			}
 			PLOG_VERBOSE << "Unprotected SRTP packet, size=" << size;
+			message->type = Message::Type::Binary;
+			auto rtp = (RTP *)message->data();
+			message->stream = rtp->ssrc();
 		}
 
 		message->resize(size);
@@ -181,23 +238,12 @@ void DtlsSrtpTransport::incoming(message_ptr message) {
 	}
 }
 
-void DtlsSrtpTransport::postCreation() {
-#if USE_GNUTLS
-	PLOG_DEBUG << "Setting SRTP profile (GnuTLS)";
-	gnutls::check(gnutls_srtp_set_profile(mSession, GNUTLS_SRTP_AES128_CM_HMAC_SHA1_80),
-	              "Failed to set SRTP profile");
-#else
-	PLOG_DEBUG << "Setting SRTP profile (OpenSSL)";
-	// returns 0 on success, 1 on error
-	if (SSL_set_tlsext_use_srtp(mSsl, "SRTP_AES128_CM_SHA1_80"), "Failed to set SRTP profile")
-		throw std::runtime_error("Failed to set SRTP profile: " + openssl::error_string(ERR_get_error()));
-#endif
-}
-
 void DtlsSrtpTransport::postHandshake() {
 	if (mInitDone)
 		return;
 
+	static_assert(SRTP_AES_ICM_128_KEY_LEN_WSALT == SRTP_AES_128_KEY_LEN + SRTP_SALT_LEN);
+
 	const size_t materialLen = SRTP_AES_ICM_128_KEY_LEN_WSALT * 2;
 	unsigned char material[materialLen];
 	const unsigned char *clientKey, *clientSalt, *serverKey, *serverSalt;
@@ -239,28 +285,48 @@ void DtlsSrtpTransport::postHandshake() {
 		throw std::runtime_error("Failed to derive SRTP keys: " +
 		                         openssl::error_string(ERR_get_error()));
 
+	// Order is client key, server key, client salt, and server salt
 	clientKey = material;
-	clientSalt = clientKey + SRTP_AES_128_KEY_LEN;
-
-	serverKey = material + SRTP_AES_ICM_128_KEY_LEN_WSALT;
-	serverSalt = serverKey + SRTP_AES_128_KEY_LEN;
+	serverKey = clientKey + SRTP_AES_128_KEY_LEN;
+	clientSalt = serverKey + SRTP_AES_128_KEY_LEN;
+	serverSalt = clientSalt + SRTP_SALT_LEN;
 #endif
 
-	unsigned char clientSessionKey[SRTP_AES_ICM_128_KEY_LEN_WSALT];
-	std::memcpy(clientSessionKey, clientKey, SRTP_AES_128_KEY_LEN);
-	std::memcpy(clientSessionKey + SRTP_AES_128_KEY_LEN, clientSalt, SRTP_SALT_LEN);
+	std::memcpy(mClientSessionKey, clientKey, SRTP_AES_128_KEY_LEN);
+	std::memcpy(mClientSessionKey + SRTP_AES_128_KEY_LEN, clientSalt, SRTP_SALT_LEN);
 
-	unsigned char serverSessionKey[SRTP_AES_ICM_128_KEY_LEN_WSALT];
-	std::memcpy(serverSessionKey, serverKey, SRTP_AES_128_KEY_LEN);
-	std::memcpy(serverSessionKey + SRTP_AES_128_KEY_LEN, serverSalt, SRTP_SALT_LEN);
+	std::memcpy(mServerSessionKey, serverKey, SRTP_AES_128_KEY_LEN);
+	std::memcpy(mServerSessionKey + SRTP_AES_128_KEY_LEN, serverSalt, SRTP_SALT_LEN);
+
+	// Add SSRC=1 as an inbound because that is what Chrome does.
+	srtp_policy_t inbound = {};
+	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&inbound.rtp);
+	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&inbound.rtcp);
+	inbound.ssrc.type = ssrc_specific;
+	inbound.ssrc.value = 1;
+	inbound.key = mIsClient ? mServerSessionKey : mClientSessionKey;
+	inbound.next = nullptr;
+
+	if (srtp_err_status_t err = srtp_add_stream(mSrtpIn, &inbound)) {
+		throw std::runtime_error("SRTP add inbound stream failed, status=" +
+		                         to_string(static_cast<int>(err)));
+	}
+
+	mInitDone = true;
+}
+
+void DtlsSrtpTransport::addSSRC(uint32_t ssrc) {
+	if (!mInitDone)
+		throw std::logic_error("Attempted to add SSRC before SRTP keying material is derived");
 
 	srtp_policy_t inbound = {};
 	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&inbound.rtp);
 	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&inbound.rtcp);
-	inbound.ssrc.type = ssrc_any_inbound;
-	inbound.ssrc.value = 0;
-	inbound.key = mIsClient ? serverSessionKey : clientSessionKey;
+	inbound.ssrc.type = ssrc_specific;
+	inbound.ssrc.value = ssrc;
+	inbound.key = mIsClient ? mServerSessionKey : mClientSessionKey;
 	inbound.next = nullptr;
+	inbound.allow_repeat_tx = true;
 
 	if (srtp_err_status_t err = srtp_add_stream(mSrtpIn, &inbound))
 		throw std::runtime_error("SRTP add inbound stream failed, status=" +
@@ -269,16 +335,15 @@ void DtlsSrtpTransport::postHandshake() {
 	srtp_policy_t outbound = {};
 	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&outbound.rtp);
 	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&outbound.rtcp);
-	outbound.ssrc.type = ssrc_any_outbound;
-	outbound.ssrc.value = 0;
-	outbound.key = mIsClient ? clientSessionKey : serverSessionKey;
+	outbound.ssrc.type = ssrc_specific;
+	outbound.ssrc.value = ssrc;
+	outbound.key = mIsClient ? mClientSessionKey : mServerSessionKey;
 	outbound.next = nullptr;
+	outbound.allow_repeat_tx = true;
 
 	if (srtp_err_status_t err = srtp_add_stream(mSrtpOut, &outbound))
 		throw std::runtime_error("SRTP add outbound stream failed, status=" +
 		                         to_string(static_cast<int>(err)));
-
-	mInitDone = true;
 }
 
 } // namespace rtc

src/dtlssrtptransport.hpp

@@ -24,7 +24,13 @@
 
 #if RTC_ENABLE_MEDIA
 
+#if RTC_SYSTEM_SRTP
 #include <srtp2/srtp.h>
+#else
+#include "srtp.h"
+#endif
+
+#include <atomic>
 
 namespace rtc {
 
@@ -39,16 +45,19 @@ public:
 	~DtlsSrtpTransport();
 
 	bool sendMedia(message_ptr message);
+	void addSSRC(uint32_t ssrc);
 
 private:
 	void incoming(message_ptr message) override;
-	void postCreation() override;
 	void postHandshake() override;
 
 	message_callback mSrtpRecvCallback;
 
 	srtp_t mSrtpIn, mSrtpOut;
-	bool mInitDone = false;
+
+	std::atomic<bool> mInitDone = false;
+	unsigned char mClientSessionKey[SRTP_AES_ICM_128_KEY_LEN_WSALT];
+	unsigned char mServerSessionKey[SRTP_AES_ICM_128_KEY_LEN_WSALT];
 };
 
 } // namespace rtc

src/dtlstransport.cpp

@@ -85,11 +85,6 @@ DtlsTransport::DtlsTransport(shared_ptr<IceTransport> lower, certificate_ptr cer
 		gnutls_transport_set_pull_function(mSession, ReadCallback);
 		gnutls_transport_set_pull_timeout_function(mSession, TimeoutCallback);
 
-		postCreation();
-
-		mRecvThread = std::thread(&DtlsTransport::runRecvLoop, this);
-		registerIncoming();
-
 	} catch (...) {
 		gnutls_deinit(mSession);
 		throw;
@@ -102,6 +97,15 @@ DtlsTransport::~DtlsTransport() {
 	gnutls_deinit(mSession);
 }
 
+void DtlsTransport::start() {
+	Transport::start();
+
+	registerIncoming();
+
+	PLOG_DEBUG << "Starting DTLS recv thread";
+	mRecvThread = std::thread(&DtlsTransport::runRecvLoop, this);
+}
+
 bool DtlsTransport::stop() {
 	if (!Transport::stop())
 		return false;
@@ -139,17 +143,12 @@ void DtlsTransport::incoming(message_ptr message) {
 	mIncomingQueue.push(message);
 }
 
-void DtlsTransport::postCreation() {
-	// Dummy
-}
-
 void DtlsTransport::postHandshake() {
 	// Dummy
 }
 
 void DtlsTransport::runRecvLoop() {
 	const size_t maxMtu = 4096;
-
 	// Handshake loop
 	try {
 		changeState(State::Connecting);
@@ -178,8 +177,8 @@ void DtlsTransport::runRecvLoop() {
 	// Receive loop
 	try {
 		PLOG_INFO << "DTLS handshake finished";
-		changeState(State::Connected);
 		postHandshake();
+		changeState(State::Connected);
 
 		const size_t bufferSize = maxMtu;
 		char buffer[bufferSize];
@@ -259,7 +258,7 @@ ssize_t DtlsTransport::WriteCallback(gnutls_transport_ptr_t ptr, const void *dat
 ssize_t DtlsTransport::ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_t maxlen) {
 	DtlsTransport *t = static_cast<DtlsTransport *>(ptr);
 	if (auto next = t->mIncomingQueue.pop()) {
-		auto message = *next;
+		message_ptr message = std::move(*next);
 		ssize_t len = std::min(maxlen, message->size());
 		std::memcpy(data, message->data(), len);
 		gnutls_transport_set_errno(t->mSession, 0);
@@ -272,9 +271,9 @@ ssize_t DtlsTransport::ReadCallback(gnutls_transport_ptr_t ptr, void *data, size
 
 int DtlsTransport::TimeoutCallback(gnutls_transport_ptr_t ptr, unsigned int ms) {
 	DtlsTransport *t = static_cast<DtlsTransport *>(ptr);
-	t->mIncomingQueue.wait(ms != GNUTLS_INDEFINITE_TIMEOUT ? std::make_optional(milliseconds(ms))
-	                                                       : nullopt);
-	return !t->mIncomingQueue.empty() ? 1 : 0;
+	bool notEmpty = t->mIncomingQueue.wait(
+	    ms != GNUTLS_INDEFINITE_TIMEOUT ? std::make_optional(milliseconds(ms)) : nullopt);
+	return notEmpty ? 1 : 0;
 }
 
 #else // USE_GNUTLS==0
@@ -364,9 +363,6 @@ DtlsTransport::DtlsTransport(shared_ptr<IceTransport> lower, shared_ptr<Certific
 		SSL_set_options(mSsl, SSL_OP_SINGLE_ECDH_USE);
 		SSL_set_tmp_ecdh(mSsl, ecdh.get());
 
-		mRecvThread = std::thread(&DtlsTransport::runRecvLoop, this);
-		registerIncoming();
-
 	} catch (...) {
 		if (mSsl)
 			SSL_free(mSsl);
@@ -383,6 +379,15 @@ DtlsTransport::~DtlsTransport() {
 	SSL_CTX_free(mCtx);
 }
 
+void DtlsTransport::start() {
+	Transport::start();
+
+	registerIncoming();
+
+	PLOG_DEBUG << "Starting DTLS recv thread";
+	mRecvThread = std::thread(&DtlsTransport::runRecvLoop, this);
+}
+
 bool DtlsTransport::stop() {
 	if (!Transport::stop())
 		return false;
@@ -414,10 +419,6 @@ void DtlsTransport::incoming(message_ptr message) {
 	mIncomingQueue.push(message);
 }
 
-void DtlsTransport::postCreation() {
-	// Dummy
-}
-
 void DtlsTransport::postHandshake() {
 	// Dummy
 }
@@ -434,10 +435,10 @@ void DtlsTransport::runRecvLoop() {
 
 		const size_t bufferSize = maxMtu;
 		byte buffer[bufferSize];
-		while (true) {
+		while (mIncomingQueue.running()) {
 			// Process pending messages
-			while (!mIncomingQueue.empty()) {
-				auto message = *mIncomingQueue.pop();
+			while (auto next = mIncomingQueue.tryPop()) {
+				message_ptr message = std::move(*next);
 				BIO_write(mInBio, message->data(), int(message->size()));
 
 				if (state() == State::Connecting) {
@@ -452,8 +453,8 @@ void DtlsTransport::runRecvLoop() {
 						SSL_set_mtu(mSsl, maxMtu + 1);
 
 						PLOG_INFO << "DTLS handshake finished";
-						changeState(State::Connected);
 						postHandshake();
+						changeState(State::Connected);
 					}
 				} else {
 					ret = SSL_read(mSsl, buffer, bufferSize);
@@ -491,8 +492,7 @@ void DtlsTransport::runRecvLoop() {
 				}
 			}
 
-			if (!mIncomingQueue.wait(duration))
-				break; // queue is stopped
+			mIncomingQueue.wait(duration);
 		}
 	} catch (const std::exception &e) {
 		PLOG_ERROR << "DTLS recv: " << e.what();
@@ -575,4 +575,3 @@ long DtlsTransport::BioMethodCtrl(BIO * /*bio*/, int cmd, long /*num*/, void * /
 #endif
 
 } // namespace rtc
-

src/dtlstransport.hpp

@@ -47,12 +47,12 @@ public:
 	              verifier_callback verifierCallback, state_callback stateChangeCallback);
 	~DtlsTransport();
 
+	virtual void start() override;
 	virtual bool stop() override;
 	virtual bool send(message_ptr message) override; // false if dropped
 
 protected:
 	virtual void incoming(message_ptr message) override;
-	virtual void postCreation();
 	virtual void postHandshake();
 	void runRecvLoop();
 
@@ -92,4 +92,3 @@ protected:
 } // namespace rtc
 
 #endif
-

src/icetransport.cpp

@@ -46,11 +46,12 @@ using std::chrono::system_clock;
 
 namespace rtc {
 
-IceTransport::IceTransport(const Configuration &config, Description::Role role,
-                           candidate_callback candidateCallback, state_callback stateChangeCallback,
+IceTransport::IceTransport(const Configuration &config, candidate_callback candidateCallback,
+                           state_callback stateChangeCallback,
                            gathering_state_callback gatheringStateChangeCallback)
-    : Transport(nullptr, std::move(stateChangeCallback)), mRole(role), mMid("0"),
-      mGatheringState(GatheringState::New), mCandidateCallback(std::move(candidateCallback)),
+    : Transport(nullptr, std::move(stateChangeCallback)), mRole(Description::Role::ActPass),
+      mMid("0"), mGatheringState(GatheringState::New),
+      mCandidateCallback(std::move(candidateCallback)),
       mGatheringStateChangeCallback(std::move(gatheringStateChangeCallback)),
       mAgent(nullptr, nullptr) {
 
@@ -58,8 +59,32 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 	if (config.enableIceTcp) {
 		PLOG_WARNING << "ICE-TCP is not supported with libjuice";
 	}
+
+	juice_log_level_t level;
+	auto logger = plog::get();
+	switch (logger ? logger->getMaxSeverity() : plog::none) {
+	case plog::none:
+		level = JUICE_LOG_LEVEL_NONE;
+		break;
+	case plog::fatal:
+		level = JUICE_LOG_LEVEL_VERBOSE;
+		break;
+	case plog::error:
+		level = JUICE_LOG_LEVEL_ERROR;
+		break;
+	case plog::warning:
+		level = JUICE_LOG_LEVEL_WARN;
+		break;
+	case plog::info:
+	case plog::debug: // juice debug is output as verbose
+		level = JUICE_LOG_LEVEL_INFO;
+		break;
+	default:
+		level = JUICE_LOG_LEVEL_VERBOSE;
+		break;
+	}
 	juice_set_log_handler(IceTransport::LogCallback);
-	juice_set_log_level(JUICE_LOG_LEVEL_VERBOSE);
+	juice_set_log_level(level);
 
 	juice_config_t jconfig = {};
 	jconfig.cb_state_changed = IceTransport::StateChangeCallback;
@@ -106,9 +131,7 @@ IceTransport::~IceTransport() {
 	mAgent.reset();
 }
 
-bool IceTransport::stop() {
-	return Transport::stop();
-}
+bool IceTransport::stop() { return Transport::stop(); }
 
 Description::Role IceTransport::role() const { return mRole; }
 
@@ -117,15 +140,24 @@ Description IceTransport::getLocalDescription(Description::Type type) const {
 	if (juice_get_local_description(mAgent.get(), sdp, JUICE_MAX_SDP_STRING_LEN) < 0)
 		throw std::runtime_error("Failed to generate local SDP");
 
-	return Description(string(sdp), type, mRole);
+	// RFC 5763: The endpoint that is the offerer MUST use the setup attribute value of
+	// setup:actpass.
+	// See https://tools.ietf.org/html/rfc5763#section-5
+	return Description(string(sdp), type,
+	                   type == Description::Type::Offer ? Description::Role::ActPass : mRole);
 }
 
 void IceTransport::setRemoteDescription(const Description &description) {
+	if (mRole == Description::Role::ActPass)
 		mRole = description.role() == Description::Role::Active ? Description::Role::Passive
 		                                                        : Description::Role::Active;
-	mMid = description.dataMid();
-	if (juice_set_remote_description(mAgent.get(), string(description).c_str()) < 0)
-		throw std::runtime_error("Failed to parse remote SDP");
+	if (mRole == description.role())
+		throw std::logic_error("Incompatible roles with remote description");
+
+	mMid = description.bundleMid();
+	if (juice_set_remote_description(mAgent.get(),
+	                                 description.generateApplicationSdp("\r\n").c_str()) < 0)
+		throw std::runtime_error("Failed to parse ICE settings from remote SDP");
 }
 
 bool IceTransport::addRemoteCandidate(const Candidate &candidate) {
@@ -162,6 +194,24 @@ std::optional<string> IceTransport::getRemoteAddress() const {
 	return nullopt;
 }
 
+bool IceTransport::getSelectedCandidatePair(Candidate *local, Candidate *remote) {
+	char sdpLocal[JUICE_MAX_CANDIDATE_SDP_STRING_LEN];
+	char sdpRemote[JUICE_MAX_CANDIDATE_SDP_STRING_LEN];
+	if (juice_get_selected_candidates(mAgent.get(), sdpLocal, JUICE_MAX_CANDIDATE_SDP_STRING_LEN,
+	                                  sdpRemote, JUICE_MAX_CANDIDATE_SDP_STRING_LEN) == 0) {
+		if (local) {
+			*local = Candidate(sdpLocal, mMid);
+			local->resolve(Candidate::ResolveMode::Simple);
+		}
+		if (remote) {
+			*remote = Candidate(sdpRemote, mMid);
+			remote->resolve(Candidate::ResolveMode::Simple);
+		}
+		return true;
+	}
+	return false;
+}
+
 bool IceTransport::send(message_ptr message) {
 	auto s = state();
 	if (!message || (s != State::Connected && s != State::Completed))
@@ -273,11 +323,12 @@ void IceTransport::LogCallback(juice_log_level_t level, const char *message) {
 
 namespace rtc {
 
-IceTransport::IceTransport(const Configuration &config, Description::Role role,
-                           candidate_callback candidateCallback, state_callback stateChangeCallback,
+IceTransport::IceTransport(const Configuration &config, candidate_callback candidateCallback,
+                           state_callback stateChangeCallback,
                            gathering_state_callback gatheringStateChangeCallback)
-    : Transport(nullptr, std::move(stateChangeCallback)), mRole(role), mMid("0"),
-      mGatheringState(GatheringState::New), mCandidateCallback(std::move(candidateCallback)),
+    : Transport(nullptr, std::move(stateChangeCallback)), mRole(Description::Role::ActPass),
+      mMid("0"), mGatheringState(GatheringState::New),
+      mCandidateCallback(std::move(candidateCallback)),
       mGatheringStateChangeCallback(std::move(gatheringStateChangeCallback)),
       mNiceAgent(nullptr, nullptr), mMainLoop(nullptr, nullptr) {
 
@@ -356,8 +407,11 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 		hints.ai_protocol = IPPROTO_UDP;
 		hints.ai_flags = AI_ADDRCONFIG;
 		struct addrinfo *result = nullptr;
-		if (getaddrinfo(server.hostname.c_str(), server.service.c_str(), &hints, &result) != 0)
+		if (getaddrinfo(server.hostname.c_str(), server.service.c_str(), &hints, &result) != 0) {
+			PLOG_WARNING << "Unable to resolve STUN server address: " << server.hostname << ':'
+			             << server.service;
 			continue;
+		}
 
 		for (auto p = result; p; p = p->ai_next) {
 			if (p->ai_family == AF_INET) {
@@ -399,8 +453,11 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 		    server.relayType == IceServer::RelayType::TurnUdp ? IPPROTO_UDP : IPPROTO_TCP;
 		hints.ai_flags = AI_ADDRCONFIG;
 		struct addrinfo *result = nullptr;
-		if (getaddrinfo(server.hostname.c_str(), server.service.c_str(), &hints, &result) != 0)
+		if (getaddrinfo(server.hostname.c_str(), server.service.c_str(), &hints, &result) != 0) {
+			PLOG_WARNING << "Unable to resolve TURN server address: " << server.hostname << ':'
+			             << server.service;
 			continue;
+		}
 
 		for (auto p = result; p; p = p->ai_next) {
 			if (p->ai_family == AF_INET || p->ai_family == AF_INET6) {
@@ -477,18 +534,28 @@ Description IceTransport::getLocalDescription(Description::Type type) const {
 
 	std::unique_ptr<gchar[], void (*)(void *)> sdp(nice_agent_generate_local_sdp(mNiceAgent.get()),
 	                                               g_free);
-	return Description(string(sdp.get()), type, mRole);
+
+	// RFC 5763: The endpoint that is the offerer MUST use the setup attribute value of
+	// setup:actpass.
+	// See https://tools.ietf.org/html/rfc5763#section-5
+	return Description(string(sdp.get()), type,
+	                   type == Description::Type::Offer ? Description::Role::ActPass : mRole);
 }
 
 void IceTransport::setRemoteDescription(const Description &description) {
+	if (mRole == Description::Role::ActPass)
 		mRole = description.role() == Description::Role::Active ? Description::Role::Passive
 		                                                        : Description::Role::Active;
-	mMid = description.dataMid();
+	if (mRole == description.role())
+		throw std::logic_error("Incompatible roles with remote description");
+
+	mMid = description.bundleMid();
 	mTrickleTimeout = !description.ended() ? 30s : 0s;
 
 	// Warning: libnice expects "\n" as end of line
-	if (nice_agent_parse_remote_sdp(mNiceAgent.get(), description.generateSdp("\n").c_str()) < 0)
-		throw std::runtime_error("Failed to parse remote SDP");
+	if (nice_agent_parse_remote_sdp(mNiceAgent.get(),
+	                                description.generateApplicationSdp("\n").c_str()) < 0)
+		throw std::runtime_error("Failed to parse ICE settings from remote SDP");
 }
 
 bool IceTransport::addRemoteCandidate(const Candidate &candidate) {
@@ -497,12 +564,14 @@ bool IceTransport::addRemoteCandidate(const Candidate &candidate) {
 		return false;
 
 	// Warning: the candidate string must start with "a=candidate:" and it must not end with a
-	// newline, else libnice will reject it.
+	// newline or whitespace, else libnice will reject it.
 	string sdp(candidate);
 	NiceCandidate *cand =
 	    nice_agent_parse_remote_candidate_sdp(mNiceAgent.get(), mStreamId, sdp.c_str());
-	if (!cand)
+	if (!cand) {
+		PLOG_WARNING << "Rejected ICE candidate: " << sdp;
 		return false;
+	}
 
 	GSList *list = g_slist_append(nullptr, cand);
 	int ret = nice_agent_set_remote_candidates(mNiceAgent.get(), mStreamId, 1, list);
@@ -622,7 +691,8 @@ void IceTransport::CandidateCallback(NiceAgent *agent, NiceCandidate *candidate,
 	g_free(cand);
 }
 
-void IceTransport::GatheringDoneCallback(NiceAgent *agent, guint streamId, gpointer userData) {
+void IceTransport::GatheringDoneCallback(NiceAgent * /*agent*/, guint /*streamId*/,
+                                         gpointer userData) {
 	auto iceTransport = static_cast<rtc::IceTransport *>(userData);
 	try {
 		iceTransport->processGatheringDone();
@@ -631,8 +701,8 @@ void IceTransport::GatheringDoneCallback(NiceAgent *agent, guint streamId, gpoin
 	}
 }
 
-void IceTransport::StateChangeCallback(NiceAgent *agent, guint streamId, guint componentId,
-                                       guint state, gpointer userData) {
+void IceTransport::StateChangeCallback(NiceAgent * /*agent*/, guint /*streamId*/,
+                                       guint /*componentId*/, guint state, gpointer userData) {
 	auto iceTransport = static_cast<rtc::IceTransport *>(userData);
 	try {
 		iceTransport->processStateChange(state);
@@ -641,8 +711,8 @@ void IceTransport::StateChangeCallback(NiceAgent *agent, guint streamId, guint c
 	}
 }
 
-void IceTransport::RecvCallback(NiceAgent *agent, guint streamId, guint componentId, guint len,
-                                gchar *buf, gpointer userData) {
+void IceTransport::RecvCallback(NiceAgent * /*agent*/, guint /*streamId*/, guint /*componentId*/,
+                                guint len, gchar *buf, gpointer userData) {
 	auto iceTransport = static_cast<rtc::IceTransport *>(userData);
 	try {
 		PLOG_VERBOSE << "Incoming size=" << len;
@@ -663,8 +733,8 @@ gboolean IceTransport::TimeoutCallback(gpointer userData) {
 	return FALSE;
 }
 
-void IceTransport::LogCallback(const gchar *logDomain, GLogLevelFlags logLevel,
-                               const gchar *message, gpointer userData) {
+void IceTransport::LogCallback(const gchar * /*logDomain*/, GLogLevelFlags logLevel,
+                               const gchar *message, gpointer /*userData*/) {
 	plog::Severity severity;
 	unsigned int flags = logLevel & G_LOG_LEVEL_MASK;
 	if (flags & G_LOG_LEVEL_ERROR)
@@ -683,58 +753,28 @@ void IceTransport::LogCallback(const gchar *logDomain, GLogLevelFlags logLevel,
 	PLOG(severity) << "nice: " << message;
 }
 
-bool IceTransport::getSelectedCandidatePair(CandidateInfo *localInfo, CandidateInfo *remoteInfo) {
-	NiceCandidate *local, *remote;
-	gboolean result = nice_agent_get_selected_pair(mNiceAgent.get(), mStreamId, 1, &local, &remote);
-
-	if (!result)
+bool IceTransport::getSelectedCandidatePair(Candidate *local, Candidate *remote) {
+	NiceCandidate *niceLocal, *niceRemote;
+	if (!nice_agent_get_selected_pair(mNiceAgent.get(), mStreamId, 1, &niceLocal, &niceRemote))
 		return false;
 
-	char ipaddr[INET6_ADDRSTRLEN];
-	nice_address_to_string(&local->addr, ipaddr);
-	localInfo->address = std::string(ipaddr);
-	localInfo->port = nice_address_get_port(&local->addr);
-	localInfo->type = IceTransport::NiceTypeToCandidateType(local->type);
-	localInfo->transportType =
-	    IceTransport::NiceTransportTypeToCandidateTransportType(local->transport);
+	gchar *sdpLocal = nice_agent_generate_local_candidate_sdp(mNiceAgent.get(), niceLocal);
+	if (local)
+		*local = Candidate(sdpLocal, mMid);
+	g_free(sdpLocal);
 
-	nice_address_to_string(&remote->addr, ipaddr);
-	remoteInfo->address = std::string(ipaddr);
-	remoteInfo->port = nice_address_get_port(&remote->addr);
-	remoteInfo->type = IceTransport::NiceTypeToCandidateType(remote->type);
-	remoteInfo->transportType =
-	    IceTransport::NiceTransportTypeToCandidateTransportType(remote->transport);
+	gchar *sdpRemote = nice_agent_generate_local_candidate_sdp(mNiceAgent.get(), niceRemote);
+	if (remote)
+		*remote = Candidate(sdpRemote, mMid);
+	g_free(sdpRemote);
 
+	if (local)
+		local->resolve(Candidate::ResolveMode::Simple);
+	if (remote)
+		remote->resolve(Candidate::ResolveMode::Simple);
 	return true;
 }
 
-const CandidateType IceTransport::NiceTypeToCandidateType(NiceCandidateType type) {
-	switch (type) {
-	case NiceCandidateType::NICE_CANDIDATE_TYPE_PEER_REFLEXIVE:
-		return CandidateType::PeerReflexive;
-	case NiceCandidateType::NICE_CANDIDATE_TYPE_RELAYED:
-		return CandidateType::Relayed;
-	case NiceCandidateType::NICE_CANDIDATE_TYPE_SERVER_REFLEXIVE:
-		return CandidateType::ServerReflexive;
-	default:
-		return CandidateType::Host;
-	}
-}
-
-const CandidateTransportType
-IceTransport::NiceTransportTypeToCandidateTransportType(NiceCandidateTransport type) {
-	switch (type) {
-	case NiceCandidateTransport::NICE_CANDIDATE_TRANSPORT_TCP_ACTIVE:
-		return CandidateTransportType::TcpActive;
-	case NiceCandidateTransport::NICE_CANDIDATE_TRANSPORT_TCP_PASSIVE:
-		return CandidateTransportType::TcpPassive;
-	case NiceCandidateTransport::NICE_CANDIDATE_TRANSPORT_TCP_SO:
-		return CandidateTransportType::TcpSo;
-	default:
-		return CandidateTransportType::Udp;
-	}
-}
-
 } // namespace rtc
 
 #endif

src/icetransport.hpp

@@ -20,8 +20,8 @@
 #define RTC_ICE_TRANSPORT_H
 
 #include "candidate.hpp"
-#include "description.hpp"
 #include "configuration.hpp"
+#include "description.hpp"
 #include "include.hpp"
 #include "peerconnection.hpp"
 #include "transport.hpp"
@@ -45,8 +45,8 @@ public:
 	using candidate_callback = std::function<void(const Candidate &candidate)>;
 	using gathering_state_callback = std::function<void(GatheringState state)>;
 
-	IceTransport(const Configuration &config, Description::Role role,
-	             candidate_callback candidateCallback, state_callback stateChangeCallback,
+	IceTransport(const Configuration &config, candidate_callback candidateCallback,
+	             state_callback stateChangeCallback,
 	             gathering_state_callback gatheringStateChangeCallback);
 	~IceTransport();
 
@@ -63,9 +63,7 @@ public:
 	bool stop() override;
 	bool send(message_ptr message) override; // false if dropped
 
-#if USE_NICE
-	bool getSelectedCandidatePair(CandidateInfo *local, CandidateInfo *remote);
-#endif
+	bool getSelectedCandidatePair(Candidate *local, Candidate *remote);
 
 private:
 	bool outgoing(message_ptr message) override;
@@ -113,8 +111,6 @@ private:
 	static gboolean TimeoutCallback(gpointer userData);
 	static void LogCallback(const gchar *log_domain, GLogLevelFlags log_level, const gchar *message,
 	                        gpointer user_data);
-	static const CandidateType NiceTypeToCandidateType(NiceCandidateType type);
-	static const CandidateTransportType NiceTransportTypeToCandidateTransportType(NiceCandidateTransport type);
 #endif
 };
 

src/init.cpp

@@ -142,4 +142,3 @@ Init::~Init() {
 }
 
 } // namespace rtc
-

src/log.cpp

@@ -24,6 +24,8 @@
 #include "plog/Log.h"
 #include "plog/Logger.h"
 
+#include <mutex>
+
 namespace rtc {
 
 void InitLogger(LogLevel level) { InitLogger(static_cast<plog::Severity>(level)); }
@@ -31,6 +33,8 @@ void InitLogger(LogLevel level) { InitLogger(static_cast<plog::Severity>(level))
 void InitLogger(plog::Severity severity, plog::IAppender *appender) {
 	static plog::ColorConsoleAppender<plog::TxtFormatter> consoleAppender;
 	static plog::Logger<0> *logger = nullptr;
+	static std::mutex mutex;
+	std::lock_guard lock(mutex);
 	if (!logger) {
 		logger = &plog::init(severity, appender ? appender : &consoleAppender);
 		PLOG_DEBUG << "Logger initialized";
@@ -40,5 +44,4 @@ void InitLogger(plog::Severity severity, plog::IAppender *appender) {
 			logger->addAppender(appender);
 	}
 }
-}
-
+} // namespace rtc

src/message.cpp

@@ -0,0 +1,60 @@
+/**
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "message.hpp"
+
+namespace rtc {
+
+message_ptr make_message(size_t size, Message::Type type, unsigned int stream,
+                         std::shared_ptr<Reliability> reliability) {
+	auto message = std::make_shared<Message>(size, type);
+	message->stream = stream;
+	message->reliability = reliability;
+	return message;
+}
+
+message_ptr make_message(binary &&data, Message::Type type, unsigned int stream,
+                         std::shared_ptr<Reliability> reliability) {
+	auto message = std::make_shared<Message>(std::move(data), type);
+	message->stream = stream;
+	message->reliability = reliability;
+	return message;
+}
+
+message_ptr make_message(message_variant data) {
+	return std::visit( //
+	    overloaded{
+	        [&](binary data) { return make_message(std::move(data), Message::Binary); },
+	        [&](string data) {
+		        auto b = reinterpret_cast<const byte *>(data.data());
+		        return make_message(b, b + data.size(), Message::String);
+	        },
+	    },
+	    std::move(data));
+}
+
+message_variant to_variant(Message &&message) {
+	switch (message.type) {
+	case Message::String:
+		return string(reinterpret_cast<const char *>(message.data()), message.size());
+	default:
+		return std::move(message);
+	}
+}
+
+} // namespace rtc

src/processor.cpp

@@ -20,6 +20,8 @@
 
 namespace rtc {
 
+Processor::Processor(size_t limit) : mTasks(limit) {}
+
 Processor::~Processor() { join(); }
 
 void Processor::join() {
@@ -29,16 +31,13 @@ void Processor::join() {
 
 void Processor::schedule() {
 	std::unique_lock lock(mMutex);
-	if (mTasks.empty()) {
+	if (auto next = mTasks.tryPop()) {
+		ThreadPool::Instance().enqueue(std::move(*next));
+	} else {
 		// No more tasks
 		mPending = false;
 		mCondition.notify_all();
-		return;
 	}
-
-	ThreadPool::Instance().enqueue(std::move(mTasks.front()));
-	mTasks.pop();
 }
 
 } // namespace rtc
-

src/processor.hpp

@@ -22,6 +22,7 @@
 #include "include.hpp"
 #include "init.hpp"
 #include "threadpool.hpp"
+#include "queue.hpp"
 
 #include <condition_variable>
 #include <future>
@@ -34,7 +35,7 @@ namespace rtc {
 // Processed tasks in order by delegating them to the thread pool
 class Processor final {
 public:
-	Processor() = default;
+	Processor(size_t limit = 0);
 	~Processor();
 
 	Processor(const Processor &) = delete;
@@ -44,8 +45,7 @@ public:
 
 	void join();
 
-	template <class F, class... Args>
-	auto enqueue(F &&f, Args &&... args) -> invoke_future_t<F, Args...>;
+	template <class F, class... Args> void enqueue(F &&f, Args &&... args);
 
 protected:
 	void schedule();
@@ -53,38 +53,27 @@ protected:
 	// Keep an init token
 	const init_token mInitToken = Init::Token();
 
-	std::queue<std::function<void()>> mTasks;
+	Queue<std::function<void()>> mTasks;
 	bool mPending = false; // true iff a task is pending in the thread pool
 
 	mutable std::mutex mMutex;
 	std::condition_variable mCondition;
 };
 
-template <class F, class... Args>
-auto Processor::enqueue(F &&f, Args &&... args) -> invoke_future_t<F, Args...> {
+template <class F, class... Args> void Processor::enqueue(F &&f, Args &&... args) {
 	std::unique_lock lock(mMutex);
-	using R = std::invoke_result_t<std::decay_t<F>, std::decay_t<Args>...>;
-	auto task = std::make_shared<std::packaged_task<R()>>(
-	    std::bind(std::forward<F>(f), std::forward<Args>(args)...));
-	std::future<R> result = task->get_future();
-
-	auto bundle = [this, task = std::move(task)]() {
-		try {
-			(*task)();
-		} catch (const std::exception &e) {
-			PLOG_WARNING << "Unhandled exception in task: " << e.what();
-		}
-		schedule(); // chain the next task
+	auto bound = std::bind(std::forward<F>(f), std::forward<Args>(args)...);
+	auto task = [this, bound = std::move(bound)]() mutable {
+		scope_guard guard(std::bind(&Processor::schedule, this)); // chain the next task
+		return bound();
 	};
 
 	if (!mPending) {
-		ThreadPool::Instance().enqueue(std::move(bundle));
+		ThreadPool::Instance().enqueue(std::move(task));
 		mPending = true;
 	} else {
-		mTasks.emplace(std::move(bundle));
+		mTasks.push(std::move(task));
 	}
-
-	return result;
 }
 
 } // namespace rtc

src/rtcp.cpp

@@ -0,0 +1,137 @@
+/**
+ * Copyright (c) 2020 Staz Modrzynski
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rtcp.hpp"
+
+#include "track.hpp"
+#include <cmath>
+#include <utility>
+
+#ifdef _WIN32
+#include <winsock2.h>
+#else
+#include <arpa/inet.h>
+#endif
+
+namespace rtc {
+
+rtc::message_ptr RtcpReceivingSession::outgoing(rtc::message_ptr ptr) { return ptr; }
+
+rtc::message_ptr RtcpReceivingSession::incoming(rtc::message_ptr ptr) {
+	if (ptr->type == rtc::Message::Type::Binary) {
+		auto rtp = reinterpret_cast<const RTP *>(ptr->data());
+
+		// https://tools.ietf.org/html/rfc3550#appendix-A.1
+		if (rtp->version() != 2) {
+			PLOG_WARNING << "RTP packet is not version 2";
+
+			return nullptr;
+		}
+		if (rtp->payloadType() == 201 || rtp->payloadType() == 200) {
+			PLOG_WARNING << "RTP packet has a payload type indicating RR/SR";
+
+			return nullptr;
+		}
+
+		// TODO Implement the padding bit
+		if (rtp->padding()) {
+			PLOG_WARNING << "Padding processing not implemented";
+		}
+
+		mSsrc = rtp->ssrc();
+
+		return ptr;
+	}
+
+	assert(ptr->type == rtc::Message::Type::Control);
+	auto rr = reinterpret_cast<const RTCP_RR *>(ptr->data());
+	if (rr->header.payloadType() == 201) {
+		// RR
+		mSsrc = rr->senderSSRC();
+		rr->log();
+	} else if (rr->header.payloadType() == 200) {
+		// SR
+		mSsrc = rr->senderSSRC();
+		auto sr = reinterpret_cast<const RTCP_SR *>(ptr->data());
+		mSyncRTPTS = sr->rtpTimestamp();
+		mSyncNTPTS = sr->ntpTimestamp();
+		sr->log();
+
+		// TODO For the time being, we will send RR's/REMB's when we get an SR
+		pushRR(0);
+		if (mRequestedBitrate > 0)
+			pushREMB(mRequestedBitrate);
+	}
+	return nullptr;
+}
+
+void RtcpReceivingSession::requestBitrate(unsigned int newBitrate) {
+	mRequestedBitrate = newBitrate;
+
+	PLOG_DEBUG << "[GOOG-REMB] Requesting bitrate: " << newBitrate << std::endl;
+	pushREMB(newBitrate);
+}
+
+void RtcpReceivingSession::pushREMB(unsigned int bitrate) {
+	rtc::message_ptr msg =
+	    rtc::make_message(RTCP_REMB::sizeWithSSRCs(1), rtc::Message::Type::Control);
+	auto remb = reinterpret_cast<RTCP_REMB *>(msg->data());
+	remb->preparePacket(mSsrc, 1, bitrate);
+	remb->setSsrc(0, mSsrc);
+
+	send(msg);
+}
+
+void RtcpReceivingSession::pushRR(unsigned int lastSR_delay) {
+	auto msg = rtc::make_message(RTCP_RR::sizeWithReportBlocks(1), rtc::Message::Type::Control);
+	auto rr = reinterpret_cast<RTCP_RR *>(msg->data());
+	rr->preparePacket(mSsrc, 1);
+	rr->getReportBlock(0)->preparePacket(mSsrc, 0, 0, uint16_t(mGreatestSeqNo), 0, 0, mSyncNTPTS,
+	                                     lastSR_delay);
+	rr->log();
+
+	send(msg);
+}
+
+bool RtcpReceivingSession::send(message_ptr msg) {
+	try {
+		outgoingCallback(std::move(msg));
+		return true;
+	} catch (const std::exception &e) {
+		LOG_DEBUG << "RTCP tx failed: " << e.what();
+	}
+	return false;
+}
+
+bool RtcpReceivingSession::requestKeyframe() {
+	pushPLI();
+	return true; // TODO Make this false when it is impossible (i.e. Opus).
+}
+
+void RtcpReceivingSession::pushPLI() {
+	auto msg = rtc::make_message(rtc::RTCP_PLI::size(), rtc::Message::Type::Control);
+	auto *pli = (rtc::RTCP_PLI *)msg->data();
+	pli->preparePacket(mSsrc);
+	send(msg);
+}
+
+void RtcpHandler::onOutgoing(const std::function<void(rtc::message_ptr)> &cb) {
+	this->outgoingCallback = synchronized_callback<rtc::message_ptr>(cb);
+}
+} // namespace rtc

src/sctptransport.cpp

@@ -88,7 +88,7 @@ void SctpTransport::Cleanup() {
 SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
                              message_callback recvCallback, amount_callback bufferedAmountCallback,
                              state_callback stateChangeCallback)
-    : Transport(lower, std::move(stateChangeCallback)), mPort(port),
+    : Transport(lower, std::move(stateChangeCallback)), mPort(port), mPendingRecvCount(0),
       mSendQueue(0, message_size_func), mBufferedAmountCallback(std::move(bufferedAmountCallback)) {
 	onRecv(recvCallback);
 
@@ -100,11 +100,12 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
 		Instances.insert(this);
 	}
 
-	mSock = usrsctp_socket(AF_CONN, SOCK_STREAM, IPPROTO_SCTP, &SctpTransport::RecvCallback,
-	                       &SctpTransport::SendCallback, 0, this);
+	mSock = usrsctp_socket(AF_CONN, SOCK_STREAM, IPPROTO_SCTP, nullptr, nullptr, 0, nullptr);
 	if (!mSock)
 		throw std::runtime_error("Could not create SCTP socket, errno=" + std::to_string(errno));
 
+	usrsctp_set_upcall(mSock, &SctpTransport::UpcallCallback, this);
+
 	if (usrsctp_set_non_blocking(mSock, 1))
 		throw std::runtime_error("Unable to set non-blocking mode, errno=" + std::to_string(errno));
 
@@ -122,6 +123,10 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
 	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_ENABLE_STREAM_RESET, &av, sizeof(av)))
 		throw std::runtime_error("Could not set socket option SCTP_ENABLE_STREAM_RESET, errno=" +
 		                         std::to_string(errno));
+	int on = 1;
+	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_RECVRCVINFO, &on, sizeof(on)))
+		throw std::runtime_error("Could set socket option SCTP_RECVRCVINFO, errno=" +
+		                         std::to_string(errno));
 
 	struct sctp_event se = {};
 	se.se_assoc_id = SCTP_ALL_ASSOC;
@@ -148,7 +153,7 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
 
 	struct sctp_paddrparams spp = {};
 #if USE_PMTUD
-	// Enabled SCTP path MTU discovery
+	// Enable SCTP path MTU discovery
 	spp.spp_flags = SPP_PMTUD_ENABLE;
 #else
 	// Fall back to a safe MTU value.
@@ -187,9 +192,6 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
 	if (usrsctp_setsockopt(mSock, SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize)))
 		throw std::runtime_error("Could not set SCTP send buffer size, errno=" +
 		                         std::to_string(errno));
-
-	registerIncoming();
-	connect();
 }
 
 SctpTransport::~SctpTransport() {
@@ -203,6 +205,13 @@ SctpTransport::~SctpTransport() {
 	}
 }
 
+void SctpTransport::start() {
+	Transport::start();
+
+	registerIncoming();
+	connect();
+}
+
 bool SctpTransport::stop() {
 	// Transport::stop() will unregister incoming() from the lower layer, therefore we need to make
 	// sure the thread from lower layers is not blocked in incoming() by the WrittenOnce condition.
@@ -221,6 +230,7 @@ bool SctpTransport::stop() {
 
 void SctpTransport::close() {
 	if (mSock) {
+		mProcessor.join();
 		usrsctp_close(mSock);
 		mSock = nullptr;
 	}
@@ -228,9 +238,9 @@ void SctpTransport::close() {
 
 void SctpTransport::connect() {
 	if (!mSock)
-		return;
+		throw std::logic_error("Attempted SCTP connect with closed socket");
 
-	PLOG_DEBUG << "SCTP connect";
+	PLOG_DEBUG << "SCTP connecting";
 	changeState(State::Connecting);
 
 	struct sockaddr_conn sconn = {};
@@ -301,7 +311,7 @@ void SctpTransport::incoming(message_ptr message) {
 	// to be sent on our side (i.e. the local INIT) before proceeding.
 	if (!mWrittenOnce) { // test the atomic boolean is not set first to prevent a lock contention
 		std::unique_lock lock(mWriteMutex);
-		mWrittenCondition.wait(lock, [&]() { return mWrittenOnce || state() != State::Connected; });
+		mWrittenCondition.wait(lock, [&]() { return mWrittenOnce.load(); });
 	}
 
 	if (!message) {
@@ -315,10 +325,64 @@ void SctpTransport::incoming(message_ptr message) {
 	usrsctp_conninput(this, message->data(), message->size(), 0);
 }
 
+void SctpTransport::doRecv() {
+	std::lock_guard lock(mRecvMutex);
+	--mPendingRecvCount;
+	try {
+		while (true) {
+			const size_t bufferSize = 65536;
+			byte buffer[bufferSize];
+			socklen_t fromlen = 0;
+			struct sctp_rcvinfo info = {};
+			socklen_t infolen = sizeof(info);
+			unsigned int infotype = 0;
+			int flags = 0;
+			ssize_t len = usrsctp_recvv(mSock, buffer, bufferSize, nullptr, &fromlen, &info,
+			                            &infolen, &infotype, &flags);
+			if (len < 0) {
+				if (errno == EWOULDBLOCK || errno == EAGAIN || errno == ECONNRESET)
+					break;
+				else
+					throw std::runtime_error("SCTP recv failed, errno=" + std::to_string(errno));
+			}
+
+			PLOG_VERBOSE << "SCTP recv, len=" << len;
+
+			// SCTP_FRAGMENT_INTERLEAVE does not seem to work as expected for messages > 64KB,
+			// therefore partial notifications and messages need to be handled separately.
+			if (flags & MSG_NOTIFICATION) {
+				// SCTP event notification
+				mPartialNotification.insert(mPartialNotification.end(), buffer, buffer + len);
+				if (flags & MSG_EOR) {
+					// Notification is complete, process it
+					auto notification =
+					    reinterpret_cast<union sctp_notification *>(mPartialNotification.data());
+					processNotification(notification, mPartialNotification.size());
+					mPartialNotification.clear();
+				}
+			} else {
+				// SCTP message
+				mPartialMessage.insert(mPartialMessage.end(), buffer, buffer + len);
+				if (flags & MSG_EOR) {
+					// Message is complete, process it
+					if (infotype != SCTP_RECVV_RCVINFO)
+						throw std::runtime_error("Missing SCTP recv info");
+
+					processData(std::move(mPartialMessage), info.rcv_sid,
+					            PayloadId(ntohl(info.rcv_ppid)));
+					mPartialMessage.clear();
+				}
+			}
+		}
+	} catch (const std::exception &e) {
+		PLOG_WARNING << e.what();
+	}
+}
+
 bool SctpTransport::trySendQueue() {
 	// Requires mSendMutex to be locked
 	while (auto next = mSendQueue.peek()) {
-		auto message = *next;
+		message_ptr message = std::move(*next);
 		if (!trySendMessage(message))
 			return false;
 		mSendQueue.pop();
@@ -372,12 +436,12 @@ bool SctpTransport::trySendMessage(message_ptr message) {
 		spa.sendv_sndinfo.snd_flags |= SCTP_UNORDERED;
 
 	switch (reliability.type) {
-	case Reliability::TYPE_PARTIAL_RELIABLE_REXMIT:
+	case Reliability::Type::Rexmit:
 		spa.sendv_flags |= SCTP_SEND_PRINFO_VALID;
 		spa.sendv_prinfo.pr_policy = SCTP_PR_SCTP_RTX;
 		spa.sendv_prinfo.pr_value = uint32_t(std::get<int>(reliability.rexmit));
 		break;
-	case Reliability::TYPE_PARTIAL_RELIABLE_TIMED:
+	case Reliability::Type::Timed:
 		spa.sendv_flags |= SCTP_SEND_PRINFO_VALID;
 		spa.sendv_prinfo.pr_policy = SCTP_PR_SCTP_TTL;
 		spa.sendv_prinfo.pr_value = uint32_t(std::get<milliseconds>(reliability.rexmit).count());
@@ -468,46 +532,21 @@ bool SctpTransport::safeFlush() {
 	}
 }
 
-int SctpTransport::handleRecv(struct socket * /*sock*/, union sctp_sockstore /*addr*/,
-                              const byte *data, size_t len, struct sctp_rcvinfo info, int flags) {
-	try {
-		PLOG_VERBOSE << "Handle recv, len=" << len;
-		if (!len)
-			return 0; // Ignore
+void SctpTransport::handleUpcall() {
+	if (!mSock)
+		return;
 
-		// SCTP_FRAGMENT_INTERLEAVE does not seem to work as expected for messages > 64KB,
-		// therefore partial notifications and messages need to be handled separately.
-		if (flags & MSG_NOTIFICATION) {
-			// SCTP event notification
-			mPartialNotification.insert(mPartialNotification.end(), data, data + len);
-			if (flags & MSG_EOR) {
-				// Notification is complete, process it
-				processNotification(
-				    reinterpret_cast<const union sctp_notification *>(mPartialNotification.data()),
-				    mPartialNotification.size());
-				mPartialNotification.clear();
-			}
-		} else {
-			// SCTP message
-			mPartialMessage.insert(mPartialMessage.end(), data, data + len);
-			if (flags & MSG_EOR) {
-				// Message is complete, process it
-				processData(std::move(mPartialMessage), info.rcv_sid,
-				            PayloadId(htonl(info.rcv_ppid)));
-				mPartialMessage.clear();
-			}
+	PLOG_VERBOSE << "Handle upcall";
+
+	int events = usrsctp_get_events(mSock);
+
+	if (events & SCTP_EVENT_READ && mPendingRecvCount == 0) {
+		++mPendingRecvCount;
+		mProcessor.enqueue(&SctpTransport::doRecv, this);
 	}
 
-	} catch (const std::exception &e) {
-		PLOG_ERROR << "SCTP recv: " << e.what();
-		return -1;
-	}
-	return 0; // success
-}
-
-int SctpTransport::handleSend(size_t free) {
-	PLOG_VERBOSE << "Handle send, free=" << free;
-	return safeFlush() ? 0 : -1;
+	if (events & SCTP_EVENT_WRITE)
+		mProcessor.enqueue(&SctpTransport::safeFlush, this);
 }
 
 int SctpTransport::handleWrite(byte *data, size_t len, uint8_t /*tos*/, uint8_t /*set_df*/) {
@@ -596,7 +635,7 @@ void SctpTransport::processNotification(const union sctp_notification *notify, s
 	}
 
 	auto type = notify->sn_header.sn_type;
-	PLOG_VERBOSE << "Process notification, type=" << type;
+	PLOG_VERBOSE << "Processing notification, type=" << type;
 
 	switch (type) {
 	case SCTP_ASSOC_CHANGE: {
@@ -618,7 +657,8 @@ void SctpTransport::processNotification(const union sctp_notification *notify, s
 	}
 
 	case SCTP_SENDER_DRY_EVENT: {
-		// It not should be necessary since the send callback should have been called already,
+		PLOG_VERBOSE << "SCTP dry event";
+		// It should not be necessary since the send callback should have been called already,
 		// but to be sure, let's try to send now.
 		safeFlush();
 		break;
@@ -629,6 +669,28 @@ void SctpTransport::processNotification(const union sctp_notification *notify, s
 		const int count = (reset_event.strreset_length - sizeof(reset_event)) / sizeof(uint16_t);
 		const uint16_t flags = reset_event.strreset_flags;
 
+		IF_PLOG(plog::verbose) {
+			std::ostringstream desc;
+			desc << "flags=";
+			if (flags & SCTP_STREAM_RESET_OUTGOING_SSN && flags & SCTP_STREAM_RESET_INCOMING_SSN)
+				desc << "outgoing|incoming";
+			else if (flags & SCTP_STREAM_RESET_OUTGOING_SSN)
+				desc << "outgoing";
+			else if (flags & SCTP_STREAM_RESET_INCOMING_SSN)
+				desc << "incoming";
+			else
+				desc << "0";
+
+			desc << ", streams=[";
+			for (int i = 0; i < count; ++i) {
+				uint16_t streamId = reset_event.strreset_stream_list[i];
+				desc << (i != 0 ? "," : "") << streamId;
+			}
+			desc << "]";
+
+			PLOG_VERBOSE << "SCTP reset event, " << desc.str();
+		}
+
 		if (flags & SCTP_STREAM_RESET_OUTGOING_SSN) {
 			for (int i = 0; i < count; ++i) {
 				uint16_t streamId = reset_event.strreset_stream_list[i];
@@ -674,37 +736,14 @@ std::optional<milliseconds> SctpTransport::rtt() {
 	return milliseconds(status.sstat_primary.spinfo_srtt);
 }
 
-int SctpTransport::RecvCallback(struct socket *sock, union sctp_sockstore addr, void *data,
-                                size_t len, struct sctp_rcvinfo recv_info, int flags, void *ptr) {
-	auto *transport = static_cast<SctpTransport *>(ptr);
-
-	std::shared_lock lock(InstancesMutex);
-	if (Instances.find(transport) == Instances.end()) {
-		free(data);
-		return -1;
-	}
-
-	int ret =
-	    transport->handleRecv(sock, addr, static_cast<const byte *>(data), len, recv_info, flags);
-	free(data);
-	return ret;
-}
-
-int SctpTransport::SendCallback(struct socket *sock, uint32_t sb_free) {
-	struct sctp_paddrinfo paddrinfo = {};
-	socklen_t len = sizeof(paddrinfo);
-	if (usrsctp_getsockopt(sock, IPPROTO_SCTP, SCTP_GET_PEER_ADDR_INFO, &paddrinfo, &len))
-		return -1;
-
-	auto sconn = reinterpret_cast<struct sockaddr_conn *>(&paddrinfo.spinfo_address);
-	void *ptr = sconn->sconn_addr;
-	auto *transport = static_cast<SctpTransport *>(ptr);
+void SctpTransport::UpcallCallback(struct socket *, void *arg, int /* flags */) {
+	auto *transport = static_cast<SctpTransport *>(arg);
 
 	std::shared_lock lock(InstancesMutex);
 	if (Instances.find(transport) == Instances.end())
-		return -1;
+		return;
 
-	return transport->handleSend(size_t(sb_free));
+	transport->handleUpcall();
 }
 
 int SctpTransport::WriteCallback(void *ptr, void *data, size_t len, uint8_t tos, uint8_t set_df) {

src/sctptransport.hpp

@@ -21,8 +21,10 @@
 
 #include "include.hpp"
 #include "peerconnection.hpp"
+#include "processor.hpp"
 #include "queue.hpp"
 #include "transport.hpp"
+#include "processor.hpp"
 
 #include <condition_variable>
 #include <functional>
@@ -35,7 +37,7 @@
 
 namespace rtc {
 
-class SctpTransport : public Transport {
+class SctpTransport final : public Transport {
 public:
 	static void Init();
 	static void Cleanup();
@@ -46,6 +48,7 @@ public:
 	              amount_callback bufferedAmountCallback, state_callback stateChangeCallback);
 	~SctpTransport();
 
+	void start() override;
 	bool stop() override;
 	bool send(message_ptr message) override; // false if buffered
 	void closeStream(unsigned int stream);
@@ -75,15 +78,14 @@ private:
 	void close();
 	void incoming(message_ptr message) override;
 
+	void doRecv();
 	bool trySendQueue();
 	bool trySendMessage(message_ptr message);
 	void updateBufferedAmount(uint16_t streamId, long delta);
 	void sendReset(uint16_t streamId);
 	bool safeFlush();
 
-	int handleRecv(struct socket *sock, union sctp_sockstore addr, const byte *data, size_t len,
-	               struct sctp_rcvinfo recv_info, int flags);
-	int handleSend(size_t free);
+	void handleUpcall();
 	int handleWrite(byte *data, size_t len, uint8_t tos, uint8_t set_df);
 
 	void processData(binary &&data, uint16_t streamId, PayloadId ppid);
@@ -92,7 +94,9 @@ private:
 	const uint16_t mPort;
 	struct socket *mSock;
 
-	std::mutex mSendMutex;
+	Processor mProcessor;
+	std::atomic<int> mPendingRecvCount;
+	std::mutex mRecvMutex, mSendMutex;
 	Queue<message_ptr> mSendQueue;
 	std::map<uint16_t, size_t> mBufferedAmount;
 	amount_callback mBufferedAmountCallback;
@@ -108,9 +112,7 @@ private:
 	// Stats
 	std::atomic<size_t> mBytesSent = 0, mBytesReceived = 0;
 
-	static int RecvCallback(struct socket *sock, union sctp_sockstore addr, void *data, size_t len,
-	                        struct sctp_rcvinfo recv_info, int flags, void *user_data);
-	static int SendCallback(struct socket *sock, uint32_t sb_free);
+	static void UpcallCallback(struct socket *sock, void *arg, int flags);
 	static int WriteCallback(void *sctp_ptr, void *data, size_t len, uint8_t tos, uint8_t set_df);
 
 	static std::unordered_set<SctpTransport *> Instances;

src/tcptransport.cpp

@@ -54,7 +54,7 @@ SelectInterrupter::~SelectInterrupter() {
 #endif
 }
 
-int SelectInterrupter::prepare(fd_set &readfds, fd_set &writefds) {
+int SelectInterrupter::prepare(fd_set &readfds, [[maybe_unused]] fd_set &writefds) {
 	std::lock_guard lock(mMutex);
 #ifdef _WIN32
 	if (mDummySock == INVALID_SOCKET)
@@ -86,11 +86,15 @@ TcpTransport::TcpTransport(const string &hostname, const string &service, state_
     : Transport(nullptr, std::move(callback)), mHostname(hostname), mService(service) {
 
 	PLOG_DEBUG << "Initializing TCP transport";
-	mThread = std::thread(&TcpTransport::runLoop, this);
 }
 
-TcpTransport::~TcpTransport() {
-	stop();
+TcpTransport::~TcpTransport() { stop(); }
+
+void TcpTransport::start() {
+	Transport::start();
+
+	PLOG_DEBUG << "Starting TCP recv thread";
+	mThread = std::thread(&TcpTransport::runLoop, this);
 }
 
 bool TcpTransport::stop() {
@@ -208,16 +212,21 @@ void TcpTransport::connect(const sockaddr *addr, socklen_t addrlen) {
 			throw std::runtime_error(msg.str());
 		}
 
+		while (true) {
 			fd_set writefds;
 			FD_ZERO(&writefds);
 			FD_SET(mSock, &writefds);
 			struct timeval tv;
-		tv.tv_sec = 10; // TODO
+			tv.tv_sec = 10; // TODO: Make the timeout configurable
 			tv.tv_usec = 0;
 			ret = ::select(SOCKET_TO_INT(mSock) + 1, NULL, &writefds, NULL, &tv);
 
-		if (ret < 0)
+			if (ret < 0) {
+				if (sockerrno == SEINTR || sockerrno == SEAGAIN) // interrupted
+					continue;
+				else
 					throw std::runtime_error("Failed to wait for socket connection");
+			}
 
 			if (ret == 0) {
 				std::ostringstream msg;
@@ -237,7 +246,8 @@ void TcpTransport::connect(const sockaddr *addr, socklen_t addrlen) {
 			}
 
 			PLOG_DEBUG << "TCP connection to " << node << ":" << serv << " succeeded";
-
+			break;
+		}
 	} catch (...) {
 		if (mSock != INVALID_SOCKET) {
 			::closesocket(mSock);
@@ -261,7 +271,7 @@ void TcpTransport::close() {
 bool TcpTransport::trySendQueue() {
 	// mSockMutex must be locked
 	while (auto next = mSendQueue.peek()) {
-		auto message = *next;
+		message_ptr message = std::move(*next);
 		if (!trySendMessage(message)) {
 			mSendQueue.exchange(message);
 			return false;

src/tcptransport.hpp

@@ -56,6 +56,7 @@ public:
 	TcpTransport(const string &hostname, const string &service, state_callback callback);
 	~TcpTransport();
 
+	void start() override;
 	bool stop() override;
 	bool send(message_ptr message) override;
 

src/threadpool.cpp

@@ -58,11 +58,7 @@ void ThreadPool::run() {
 
 bool ThreadPool::runOne() {
 	if (auto task = dequeue()) {
-		try {
 		task();
-		} catch (const std::exception &e) {
-			PLOG_WARNING << "Unhandled exception in task: " << e.what();
-		}
 		return true;
 	}
 	return false;
@@ -79,4 +75,3 @@ std::function<void()> ThreadPool::dequeue() {
 }
 
 } // namespace rtc
-

src/threadpool.hpp

@@ -73,8 +73,15 @@ template <class F, class... Args>
 auto ThreadPool::enqueue(F &&f, Args &&... args) -> invoke_future_t<F, Args...> {
 	std::unique_lock lock(mMutex);
 	using R = std::invoke_result_t<std::decay_t<F>, std::decay_t<Args>...>;
-	auto task = std::make_shared<std::packaged_task<R()>>(
-	    std::bind(std::forward<F>(f), std::forward<Args>(args)...));
+	auto bound = std::bind(std::forward<F>(f), std::forward<Args>(args)...);
+	auto task = std::make_shared<std::packaged_task<R()>>([bound = std::move(bound)]() mutable {
+		try {
+			return bound();
+		} catch (const std::exception &e) {
+			PLOG_WARNING << e.what();
+			throw;
+		}
+	});
 	std::future<R> result = task->get_future();
 
 	mTasks.emplace([task = std::move(task), token = Init::Token()]() { return (*task)(); });

src/tls.cpp

@@ -85,10 +85,9 @@ void init() {
 	static bool done = false;
 
 	std::lock_guard lock(mutex);
-	if (!done) {
+	if (!std::exchange(done, true)) {
 		OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS | OPENSSL_INIT_LOAD_CRYPTO_STRINGS, nullptr);
 		OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, nullptr);
-		done = true;
 	}
 }
 
@@ -128,4 +127,3 @@ bool check(SSL *ssl, int ret, const string &message) {
 } // namespace rtc::openssl
 
 #endif
-

src/tls.hpp

@@ -56,12 +56,12 @@ gnutls_datum_t make_datum(char *data, size_t size);
 #include <openssl/ssl.h>
 
 #include <openssl/bio.h>
+#include <openssl/bn.h>
 #include <openssl/ec.h>
 #include <openssl/err.h>
 #include <openssl/pem.h>
-#include <openssl/x509.h>
 #include <openssl/rsa.h>
-#include <openssl/bn.h>
+#include <openssl/x509.h>
 
 #ifndef BIO_EOF
 #define BIO_EOF -1

src/tlstransport.cpp

@@ -71,11 +71,6 @@ TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_ca
 		gnutls_transport_set_pull_function(mSession, ReadCallback);
 		gnutls_transport_set_pull_timeout_function(mSession, TimeoutCallback);
 
-		postCreation();
-
-		mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
-		registerIncoming();
-
 	} catch (...) {
 		gnutls_deinit(mSession);
 		gnutls_certificate_free_credentials(mCreds);
@@ -90,6 +85,15 @@ TlsTransport::~TlsTransport() {
 	gnutls_certificate_free_credentials(mCreds);
 }
 
+void TlsTransport::start() {
+	Transport::start();
+
+	registerIncoming();
+
+	PLOG_DEBUG << "Starting TLS recv thread";
+	mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
+}
+
 bool TlsTransport::stop() {
 	if (!Transport::stop())
 		return false;
@@ -106,7 +110,7 @@ bool TlsTransport::send(message_ptr message) {
 
 	PLOG_VERBOSE << "Send size=" << message->size();
 
-	if(message->size() == 0)
+	if (message->size() == 0)
 		return true;
 
 	ssize_t ret;
@@ -124,10 +128,6 @@ void TlsTransport::incoming(message_ptr message) {
 		mIncomingQueue.stop();
 }
 
-void TlsTransport::postCreation() {
-	// Dummy
-}
-
 void TlsTransport::postHandshake() {
 	// Dummy
 }
@@ -207,10 +207,10 @@ ssize_t TlsTransport::ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_
 	message_ptr &message = t->mIncomingMessage;
 	size_t &position = t->mIncomingMessagePosition;
 
-	if(message && position >= message->size())
+	if (message && position >= message->size())
 		message.reset();
 
-	if(!message) {
+	if (!message) {
 		position = 0;
 		while (auto next = t->mIncomingQueue.pop()) {
 			message = *next;
@@ -221,15 +221,14 @@ ssize_t TlsTransport::ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_
 		}
 	}
 
-	if(message) {
+	if (message) {
 		size_t available = message->size() - position;
 		ssize_t len = std::min(maxlen, available);
 		std::memcpy(data, message->data() + position, len);
-		position+= len;
+		position += len;
 		gnutls_transport_set_errno(t->mSession, 0);
 		return len;
-	}
-	else {
+	} else {
 		// Closed
 		gnutls_transport_set_errno(t->mSession, 0);
 		return 0;
@@ -238,11 +237,9 @@ ssize_t TlsTransport::ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_
 
 int TlsTransport::TimeoutCallback(gnutls_transport_ptr_t ptr, unsigned int ms) {
 	TlsTransport *t = static_cast<TlsTransport *>(ptr);
-	if (ms != GNUTLS_INDEFINITE_TIMEOUT)
-		t->mIncomingQueue.wait(milliseconds(ms));
-	else
-		t->mIncomingQueue.wait();
-	return !t->mIncomingQueue.empty() ? 1 : 0;
+	bool notEmpty = t->mIncomingQueue.wait(
+	    ms != GNUTLS_INDEFINITE_TIMEOUT ? std::make_optional(milliseconds(ms)) : nullopt);
+	return notEmpty ? 1 : 0;
 }
 
 #else // USE_GNUTLS==0
@@ -309,11 +306,6 @@ TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_ca
 		SSL_set_options(mSsl, SSL_OP_SINGLE_ECDH_USE);
 		SSL_set_tmp_ecdh(mSsl, ecdh.get());
 
-		postCreation();
-
-		mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
-		registerIncoming();
-
 	} catch (...) {
 		if (mSsl)
 			SSL_free(mSsl);
@@ -330,6 +322,15 @@ TlsTransport::~TlsTransport() {
 	SSL_CTX_free(mCtx);
 }
 
+void TlsTransport::start() {
+	Transport::start();
+
+	registerIncoming();
+
+	PLOG_DEBUG << "Starting TLS recv thread";
+	mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
+}
+
 bool TlsTransport::stop() {
 	if (!Transport::stop())
 		return false;
@@ -369,10 +370,6 @@ void TlsTransport::incoming(message_ptr message) {
 		mIncomingQueue.stop();
 }
 
-void TlsTransport::postCreation() {
-	// Dummy
-}
-
 void TlsTransport::postHandshake() {
 	// Dummy
 }
@@ -413,7 +410,7 @@ void TlsTransport::runRecvLoop() {
 			if (!next)
 				break;
 
-			message_ptr message = *next;
+			message_ptr message = std::move(*next);
 			if (message->size() > 0)
 				BIO_write(mInBio, message->data(), int(message->size())); // Input
 			else

src/tlstransport.hpp

@@ -40,12 +40,12 @@ public:
 	TlsTransport(std::shared_ptr<TcpTransport> lower, string host, state_callback callback);
 	virtual ~TlsTransport();
 
+	void start() override;
 	bool stop() override;
 	bool send(message_ptr message) override;
 
 protected:
 	virtual void incoming(message_ptr message) override;
-	virtual void postCreation();
 	virtual void postHandshake();
 	void runRecvLoop();
 

src/track.cpp

@@ -0,0 +1,177 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "track.hpp"
+#include "dtlssrtptransport.hpp"
+#include "include.hpp"
+
+namespace rtc {
+
+using std::shared_ptr;
+using std::weak_ptr;
+
+Track::Track(Description::Media description)
+    : mMediaDescription(std::move(description)), mRecvQueue(RECV_QUEUE_LIMIT, message_size_func) {}
+
+string Track::mid() const { return mMediaDescription.mid(); }
+
+Description::Media Track::description() const { return mMediaDescription; }
+
+void Track::setDescription(Description::Media description) {
+	if (description.mid() != mMediaDescription.mid())
+		throw std::logic_error("Media description mid does not match track mid");
+
+	mMediaDescription = std::move(description);
+}
+
+void Track::close() {
+	mIsClosed = true;
+	resetCallbacks();
+	setRtcpHandler(nullptr);
+}
+
+bool Track::send(message_variant data) { return outgoing(make_message(std::move(data))); }
+
+bool Track::send(const byte *data, size_t size) {
+	return outgoing(std::make_shared<Message>(data, data + size, Message::Binary));
+}
+
+std::optional<message_variant> Track::receive() {
+	if (auto next = mRecvQueue.tryPop())
+		return to_variant(std::move(**next));
+
+	return nullopt;
+}
+
+std::optional<message_variant> Track::peek() {
+	if (auto next = mRecvQueue.peek())
+		return to_variant(std::move(**next));
+
+	return nullopt;
+}
+
+bool Track::isOpen(void) const {
+#if RTC_ENABLE_MEDIA
+	return !mIsClosed && mDtlsSrtpTransport.lock();
+#else
+	return !mIsClosed;
+#endif
+}
+
+bool Track::isClosed(void) const { return mIsClosed; }
+
+size_t Track::maxMessageSize() const {
+	return 65535 - 12 - 4; // SRTP/UDP
+}
+
+size_t Track::availableAmount() const { return mRecvQueue.amount(); }
+
+#if RTC_ENABLE_MEDIA
+void Track::open(shared_ptr<DtlsSrtpTransport> transport) {
+	mDtlsSrtpTransport = transport;
+	triggerOpen();
+}
+#endif
+
+bool Track::outgoing(message_ptr message) {
+
+	if (mRtcpHandler) {
+		message = mRtcpHandler->outgoing(message);
+		if (!message)
+			return false;
+	}
+
+	auto direction = mMediaDescription.direction();
+	if ((direction == Description::Direction::RecvOnly ||
+	     direction == Description::Direction::Inactive) &&
+	    message->type != Message::Control) {
+		PLOG_WARNING << "Track media direction does not allow transmission, dropping";
+		return false;
+	}
+
+	if (mIsClosed)
+		throw std::runtime_error("Track is closed");
+
+	if (message->size() > maxMessageSize())
+		throw std::runtime_error("Message size exceeds limit");
+
+#if RTC_ENABLE_MEDIA
+	auto transport = mDtlsSrtpTransport.lock();
+	if (!transport)
+		throw std::runtime_error("Track transport is not open");
+
+	return transport->sendMedia(message);
+#else
+	PLOG_WARNING << "Ignoring track send (not compiled with SRTP support)";
+	return false;
+#endif
+}
+
+void Track::incoming(message_ptr message) {
+	if (!message)
+		return;
+
+	if (mRtcpHandler) {
+		message = mRtcpHandler->incoming(message);
+		if (!message)
+			return;
+	}
+
+	auto direction = mMediaDescription.direction();
+	if ((direction == Description::Direction::SendOnly ||
+	     direction == Description::Direction::Inactive) &&
+	    message->type != Message::Control) {
+		PLOG_WARNING << "Track media direction does not allow reception, dropping";
+		return;
+	}
+
+	// Tail drop if queue is full
+	if (mRecvQueue.full())
+		return;
+
+	mRecvQueue.push(message);
+	triggerAvailable(mRecvQueue.size());
+}
+
+void Track::setRtcpHandler(std::shared_ptr<RtcpHandler> handler) {
+	mRtcpHandler = std::move(handler);
+	if (mRtcpHandler) {
+		mRtcpHandler->onOutgoing([&]([[maybe_unused]] const rtc::message_ptr &message) {
+#if RTC_ENABLE_MEDIA
+			auto transport = mDtlsSrtpTransport.lock();
+			if (!transport)
+				throw std::runtime_error("Track transport is not open");
+
+			return transport->sendMedia(message);
+#else
+			PLOG_WARNING << "Ignoring track send (not compiled with SRTP support)";
+			return false;
+#endif
+		});
+	}
+}
+
+bool Track::requestKeyframe() {
+	if (mRtcpHandler)
+		return mRtcpHandler->requestKeyframe();
+	return false;
+}
+
+std::shared_ptr<RtcpHandler> Track::getRtcpHandler() { return mRtcpHandler; }
+
+} // namespace rtc

src/transport.hpp

@@ -36,28 +36,30 @@ public:
 	using state_callback = std::function<void(State state)>;
 
 	Transport(std::shared_ptr<Transport> lower = nullptr, state_callback callback = nullptr)
-	    : mLower(std::move(lower)), mStateChangeCallback(std::move(callback)) {
-	}
+	    : mLower(std::move(lower)), mStateChangeCallback(std::move(callback)) {}
 
-	virtual ~Transport() {
-		stop();
-	}
+	virtual ~Transport() { stop(); }
+
+	virtual void start() { mStopped = false; }
 
 	virtual bool stop() {
-		if (mShutdown.exchange(true))
+		if (mStopped.exchange(true))
 			return false;
 
 		// We don't want incoming() to be called by the lower layer anymore
-		if (mLower)
+		if (mLower) {
+			PLOG_VERBOSE << "Unregistering incoming callback";
 			mLower->onRecv(nullptr);
-
+		}
 		return true;
 	}
 
 	void registerIncoming() {
-		if (mLower)
+		if (mLower) {
+			PLOG_VERBOSE << "Registering incoming callback";
 			mLower->onRecv(std::bind(&Transport::incoming, this, _1));
 		}
+	}
 
 	void onRecv(message_callback callback) { mRecvCallback = std::move(callback); }
 	State state() const { return mState; }
@@ -95,7 +97,7 @@ private:
 	synchronized_callback<message_ptr> mRecvCallback;
 
 	std::atomic<State> mState = State::Disconnected;
-	std::atomic<bool> mShutdown = false;
+	std::atomic<bool> mStopped = true;
 };
 
 } // namespace rtc

src/verifiedtlstransport.cpp

@@ -28,42 +28,21 @@ using std::weak_ptr;
 
 namespace rtc {
 
-#if USE_GNUTLS
-
 VerifiedTlsTransport::VerifiedTlsTransport(shared_ptr<TcpTransport> lower, string host,
                                            state_callback callback)
-    : TlsTransport(std::move(lower), std::move(host), std::move(callback)) {}
+    : TlsTransport(std::move(lower), std::move(host), std::move(callback)) {
 
-VerifiedTlsTransport::~VerifiedTlsTransport() {}
-
-void VerifiedTlsTransport::postCreation() {
+#if USE_GNUTLS
 	PLOG_DEBUG << "Setting up TLS certificate verification";
 	gnutls_session_set_verify_cert(mSession, mHost.c_str(), 0);
-}
-
-void VerifiedTlsTransport::postHandshake() {
-	// Nothing to do
-}
-
-#else // USE_GNUTLS==0
-
-VerifiedTlsTransport::VerifiedTlsTransport(shared_ptr<TcpTransport> lower, string host,
-                                           state_callback callback)
-    : TlsTransport(std::move(lower), std::move(host), std::move(callback)) {}
-
-VerifiedTlsTransport::~VerifiedTlsTransport() {}
-
-void VerifiedTlsTransport::postCreation() {
+#else
 	PLOG_DEBUG << "Setting up TLS certificate verification";
 	SSL_set_verify(mSsl, SSL_VERIFY_PEER, NULL);
 	SSL_set_verify_depth(mSsl, 4);
-}
-
-void VerifiedTlsTransport::postHandshake() {
-	// Nothing to do
-}
-
 #endif
+}
+
+VerifiedTlsTransport::~VerifiedTlsTransport() {}
 
 } // namespace rtc
 

src/verifiedtlstransport.hpp

@@ -29,10 +29,6 @@ class VerifiedTlsTransport final : public TlsTransport {
 public:
 	VerifiedTlsTransport(std::shared_ptr<TcpTransport> lower, string host, state_callback callback);
 	~VerifiedTlsTransport();
-
-protected:
-	void postCreation() override;
-	void postHandshake() override;
 };
 
 } // namespace rtc

src/websocket.cpp

@@ -38,7 +38,8 @@ namespace rtc {
 using std::shared_ptr;
 
 WebSocket::WebSocket(std::optional<Configuration> config)
-    : mConfig(config ? std::move(*config) : Configuration()) {
+    : mConfig(config ? std::move(*config) : Configuration()),
+      mRecvQueue(RECV_QUEUE_LIMIT, message_size_func) {
 	PLOG_VERBOSE << "Creating WebSocket";
 }
 
@@ -50,31 +51,45 @@ WebSocket::~WebSocket() {
 WebSocket::State WebSocket::readyState() const { return mState; }
 
 void WebSocket::open(const string &url) {
+	PLOG_VERBOSE << "Opening WebSocket to URL: " << url;
+
 	if (mState != State::Closed)
-		throw std::runtime_error("WebSocket must be closed before opening");
+		throw std::logic_error("WebSocket must be closed before opening");
 
-	static const char *rs = R"(^(([^:\/?#]+):)?(//([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?)";
-	static std::regex regex(rs, std::regex::extended);
+	// Modified regex from RFC 3986, see https://tools.ietf.org/html/rfc3986#appendix-B
+	static const char *rs =
+	    R"(^(([^:.@/?#]+):)?(/{0,2}((([^:@]*)(:([^@]*))?)@)?(([^:/?#]*)(:([^/?#]*))?))?([^?#]*)(\?([^#]*))?(#(.*))?)";
 
-	std::smatch match;
-	if (!std::regex_match(url, match, regex))
-		throw std::invalid_argument("Malformed WebSocket URL: " + url);
+	static const std::regex r(rs, std::regex::extended);
 
-	mScheme = match[2];
-	if (mScheme != "ws" && mScheme != "wss")
+	std::smatch m;
+	if (!std::regex_match(url, m, r) || m[10].length() == 0)
+		throw std::invalid_argument("Invalid WebSocket URL: " + url);
+
+	mScheme = m[2];
+	if (mScheme.empty())
+		mScheme = "ws";
+	else if (mScheme != "ws" && mScheme != "wss")
 		throw std::invalid_argument("Invalid WebSocket scheme: " + mScheme);
 
-	mHost = match[4];
-	if (auto pos = mHost.find(':'); pos != string::npos) {
-		mHostname = mHost.substr(0, pos);
-		mService = mHost.substr(pos + 1);
-	} else {
-		mHostname = mHost;
+	mHostname = m[10];
+	mService = m[12];
+	if (mService.empty()) {
 		mService = mScheme == "ws" ? "80" : "443";
+		mHost = mHostname;
+	} else {
+		mHost = mHostname + ':' + mService;
 	}
 
-	mPath = match[5];
-	if (string query = match[7]; !query.empty())
+	while (!mHostname.empty() && mHostname.front() == '[')
+		mHostname.erase(mHostname.begin());
+	while (!mHostname.empty() && mHostname.back() == ']')
+		mHostname.pop_back();
+
+	mPath = m[13];
+	if (mPath.empty())
+		mPath += '/';
+	if (string query = m[15]; !query.empty())
 		mPath += "?" + query;
 
 	changeState(State::Connecting);
@@ -100,16 +115,7 @@ void WebSocket::remoteClose() {
 	}
 }
 
-bool WebSocket::send(const std::variant<binary, string> &data) {
-	return std::visit(
-	    [&](const auto &d) {
-		    using T = std::decay_t<decltype(d)>;
-		    constexpr auto type = std::is_same_v<T, string> ? Message::String : Message::Binary;
-		    auto *b = reinterpret_cast<const byte *>(d.data());
-		    return outgoing(std::make_shared<Message>(b, b + d.size(), type));
-	    },
-	    data);
-}
+bool WebSocket::send(message_variant data) { return outgoing(make_message(std::move(data))); }
 
 bool WebSocket::isOpen() const { return mState == State::Open; }
 
@@ -117,19 +123,22 @@ bool WebSocket::isClosed() const { return mState == State::Closed; }
 
 size_t WebSocket::maxMessageSize() const { return DEFAULT_MAX_MESSAGE_SIZE; }
 
-std::optional<std::variant<binary, string>> WebSocket::receive() {
-	while (!mRecvQueue.empty()) {
-		auto message = *mRecvQueue.pop();
-		switch (message->type) {
-		case Message::String:
-			return std::make_optional(
-			    string(reinterpret_cast<const char *>(message->data()), message->size()));
-		case Message::Binary:
-			return std::make_optional(std::move(*message));
-		default:
-			// Ignore
-			break;
+std::optional<message_variant> WebSocket::receive() {
+	while (auto next = mRecvQueue.tryPop()) {
+		message_ptr message = *next;
+		if (message->type != Message::Control)
+			return to_variant(std::move(*message));
 	}
+	return nullopt;
+}
+
+std::optional<message_variant> WebSocket::peek() {
+	while (auto next = mRecvQueue.peek()) {
+		message_ptr message = *next;
+		if (message->type != Message::Control)
+			return to_variant(std::move(*message));
+
+		mRecvQueue.tryPop();
 	}
 	return nullopt;
 }
@@ -149,6 +158,11 @@ bool WebSocket::outgoing(message_ptr message) {
 }
 
 void WebSocket::incoming(message_ptr message) {
+	if (!message) {
+		remoteClose();
+		return;
+	}
+
 	if (message->type == Message::String || message->type == Message::Binary) {
 		mRecvQueue.push(message);
 		triggerAvailable(mRecvQueue.size());
@@ -156,6 +170,7 @@ void WebSocket::incoming(message_ptr message) {
 }
 
 shared_ptr<TcpTransport> WebSocket::initTcpTransport() {
+	PLOG_VERBOSE << "Starting TCP transport";
 	using State = TcpTransport::State;
 	try {
 		std::lock_guard lock(mInitMutex);
@@ -189,10 +204,11 @@ shared_ptr<TcpTransport> WebSocket::initTcpTransport() {
 		std::atomic_store(&mTcpTransport, transport);
 		if (mState == WebSocket::State::Closed) {
 			mTcpTransport.reset();
-			transport->stop();
 			throw std::runtime_error("Connection is closed");
 		}
+		transport->start();
 		return transport;
+
 	} catch (const std::exception &e) {
 		PLOG_ERROR << e.what();
 		remoteClose();
@@ -201,6 +217,7 @@ shared_ptr<TcpTransport> WebSocket::initTcpTransport() {
 }
 
 shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
+	PLOG_VERBOSE << "Starting TLS transport";
 	using State = TlsTransport::State;
 	try {
 		std::lock_guard lock(mInitMutex);
@@ -234,21 +251,23 @@ shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
 		if (!mConfig.disableTlsVerification) {
 			PLOG_WARNING << "TLS certificate verification with root CA is not supported on Windows";
 		}
-		transport = std::make_shared<TlsTransport>(lower, mHost, stateChangeCallback);
+		transport = std::make_shared<TlsTransport>(lower, mHostname, stateChangeCallback);
 #else
 		if (mConfig.disableTlsVerification)
-			transport = std::make_shared<TlsTransport>(lower, mHost, stateChangeCallback);
+			transport = std::make_shared<TlsTransport>(lower, mHostname, stateChangeCallback);
 		else
-			transport = std::make_shared<VerifiedTlsTransport>(lower, mHost, stateChangeCallback);
+			transport =
+			    std::make_shared<VerifiedTlsTransport>(lower, mHostname, stateChangeCallback);
 #endif
 
 		std::atomic_store(&mTlsTransport, transport);
 		if (mState == WebSocket::State::Closed) {
 			mTlsTransport.reset();
-			transport->stop();
 			throw std::runtime_error("Connection is closed");
 		}
+		transport->start();
 		return transport;
+
 	} catch (const std::exception &e) {
 		PLOG_ERROR << e.what();
 		remoteClose();
@@ -257,6 +276,7 @@ shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
 }
 
 shared_ptr<WsTransport> WebSocket::initWsTransport() {
+	PLOG_VERBOSE << "Starting WebSocket transport";
 	using State = WsTransport::State;
 	try {
 		std::lock_guard lock(mInitMutex);
@@ -295,9 +315,9 @@ shared_ptr<WsTransport> WebSocket::initWsTransport() {
 		std::atomic_store(&mWsTransport, transport);
 		if (mState == WebSocket::State::Closed) {
 			mWsTransport.reset();
-			transport->stop();
 			throw std::runtime_error("Connection is closed");
 		}
+		transport->start();
 		return transport;
 	} catch (const std::exception &e) {
 		PLOG_ERROR << e.what();

src/wstransport.cpp

@@ -17,9 +17,9 @@
  */
 
 #include "wstransport.hpp"
+#include "base64.hpp"
 #include "tcptransport.hpp"
 #include "tlstransport.hpp"
-#include "base64.hpp"
 
 #if RTC_ENABLE_WEBSOCKET
 
@@ -59,12 +59,22 @@ WsTransport::WsTransport(std::shared_ptr<Transport> lower, string host, string p
 
 	PLOG_DEBUG << "Initializing WebSocket transport";
 
-	registerIncoming();
-	sendHttpRequest();
+	if (mHost.empty())
+		throw std::invalid_argument("WebSocket HTTP host cannot be empty");
+
+	if (mPath.empty())
+		throw std::invalid_argument("WebSocket HTTP path cannot be empty");
 }
 
 WsTransport::~WsTransport() { stop(); }
 
+void WsTransport::start() {
+	Transport::start();
+
+	registerIncoming();
+	sendHttpRequest();
+}
+
 bool WsTransport::stop() {
 	if (!Transport::stop())
 		return false;
@@ -143,6 +153,7 @@ void WsTransport::close() {
 }
 
 bool WsTransport::sendHttpRequest() {
+	PLOG_DEBUG << "Sending WebSocket HTTP request for path " << mPath;
 	changeState(State::Connecting);
 
 	auto seed = static_cast<unsigned int>(system_clock::now().time_since_epoch().count());

src/wstransport.hpp

@@ -35,6 +35,7 @@ public:
 	            message_callback recvCallback, state_callback stateCallback);
 	~WsTransport();
 
+	void start() override;
 	bool stop() override;
 	bool send(message_ptr message) override;
 

test/benchmark.cpp

@@ -48,20 +48,20 @@ size_t benchmark(milliseconds duration) {
 
 	auto pc2 = std::make_shared<PeerConnection>(config2);
 
-	pc1->onLocalDescription([wpc2 = make_weak_ptr(pc2)](const Description &sdp) {
+	pc1->onLocalDescription([wpc2 = make_weak_ptr(pc2)](Description sdp) {
 		auto pc2 = wpc2.lock();
 		if (!pc2)
 			return;
 		cout << "Description 1: " << sdp << endl;
-		pc2->setRemoteDescription(sdp);
+		pc2->setRemoteDescription(std::move(sdp));
 	});
 
-	pc1->onLocalCandidate([wpc2 = make_weak_ptr(pc2)](const Candidate &candidate) {
+	pc1->onLocalCandidate([wpc2 = make_weak_ptr(pc2)](Candidate candidate) {
 		auto pc2 = wpc2.lock();
 		if (!pc2)
 			return;
 		cout << "Candidate 1: " << candidate << endl;
-		pc2->addRemoteCandidate(candidate);
+		pc2->addRemoteCandidate(std::move(candidate));
 	});
 
 	pc1->onStateChange([](PeerConnection::State state) { cout << "State 1: " << state << endl; });
@@ -69,20 +69,20 @@ size_t benchmark(milliseconds duration) {
 		cout << "Gathering state 1: " << state << endl;
 	});
 
-	pc2->onLocalDescription([wpc1 = make_weak_ptr(pc1)](const Description &sdp) {
+	pc2->onLocalDescription([wpc1 = make_weak_ptr(pc1)](Description sdp) {
 		auto pc1 = wpc1.lock();
 		if (!pc1)
 			return;
 		cout << "Description 2: " << sdp << endl;
-		pc1->setRemoteDescription(sdp);
+		pc1->setRemoteDescription(std::move(sdp));
 	});
 
-	pc2->onLocalCandidate([wpc1 = make_weak_ptr(pc1)](const Candidate &candidate) {
+	pc2->onLocalCandidate([wpc1 = make_weak_ptr(pc1)](Candidate candidate) {
 		auto pc1 = wpc1.lock();
 		if (!pc1)
 			return;
 		cout << "Candidate 2: " << candidate << endl;
-		pc1->addRemoteCandidate(candidate);
+		pc1->addRemoteCandidate(std::move(candidate));
 	});
 
 	pc2->onStateChange([](PeerConnection::State state) { cout << "State 2: " << state << endl; });
@@ -99,9 +99,8 @@ size_t benchmark(milliseconds duration) {
 	steady_clock::time_point startTime, openTime, receivedTime, endTime;
 
 	shared_ptr<DataChannel> dc2;
-	pc2->onDataChannel(
-	    [&dc2, &receivedSize, &receivedTime](shared_ptr<DataChannel> dc) {
-		    dc->onMessage([&receivedTime, &receivedSize](const variant<binary, string> &message) {
+	pc2->onDataChannel([&dc2, &receivedSize, &receivedTime](shared_ptr<DataChannel> dc) {
+		dc->onMessage([&receivedTime, &receivedSize](variant<binary, string> message) {
 			if (holds_alternative<binary>(message)) {
 				const auto &bin = get<binary>(message);
 				if (receivedSize == 0)
@@ -156,7 +155,8 @@ size_t benchmark(milliseconds duration) {
 
 	endTime = steady_clock::now();
 
-	auto connectDuration = duration_cast<milliseconds>(openTime - startTime);
+	auto connectDuration = duration_cast<milliseconds>(dc1->isOpen() ? openTime - startTime
+	                                                                 : steady_clock::duration(0));
 	auto transferDuration = duration_cast<milliseconds>(endTime - receivedTime);
 
 	cout << "Test duration: " << duration.count() << " ms" << endl;
@@ -169,9 +169,9 @@ size_t benchmark(milliseconds duration) {
 
 	pc1->close();
 	pc2->close();
-	this_thread::sleep_for(1s);
 
 	rtc::Cleanup();
+	this_thread::sleep_for(1s);
 	return goodput;
 }
 

test/capi_connectivity.cpp

@@ -0,0 +1,328 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <rtc/rtc.h>
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#ifdef _WIN32
+#include <windows.h>
+static void sleep(unsigned int secs) { Sleep(secs * 1000); }
+#else
+#include <unistd.h> // for sleep
+#endif
+
+#define BUFFER_SIZE 4096
+
+typedef struct {
+	rtcState state;
+	rtcGatheringState gatheringState;
+	rtcSignalingState signalingState;
+	int pc;
+	int dc;
+	bool connected;
+} Peer;
+
+static Peer *peer1 = NULL;
+static Peer *peer2 = NULL;
+
+static void RTC_API descriptionCallback(int pc, const char *sdp, const char *type, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	printf("Description %d:\n%s\n", peer == peer1 ? 1 : 2, sdp);
+	Peer *other = peer == peer1 ? peer2 : peer1;
+	rtcSetRemoteDescription(other->pc, sdp, type);
+}
+
+static void RTC_API candidateCallback(int pc, const char *cand, const char *mid, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	printf("Candidate %d: %s\n", peer == peer1 ? 1 : 2, cand);
+	Peer *other = peer == peer1 ? peer2 : peer1;
+	rtcAddRemoteCandidate(other->pc, cand, mid);
+}
+
+static void RTC_API stateChangeCallback(int pc, rtcState state, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->state = state;
+	printf("State %d: %d\n", peer == peer1 ? 1 : 2, (int)state);
+}
+
+static void RTC_API gatheringStateCallback(int pc, rtcGatheringState state, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->gatheringState = state;
+	printf("Gathering state %d: %d\n", peer == peer1 ? 1 : 2, (int)state);
+}
+
+static void RTC_API signalingStateCallback(int pc, rtcSignalingState state, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->signalingState = state;
+	printf("Signaling state %d: %d\n", peer == peer1 ? 1 : 2, (int)state);
+}
+
+static void RTC_API openCallback(int id, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->connected = true;
+	printf("DataChannel %d: Open\n", peer == peer1 ? 1 : 2);
+
+	const char *message = peer == peer1 ? "Hello from 1" : "Hello from 2";
+	rtcSendMessage(peer->dc, message, -1); // negative size indicates a null-terminated string
+}
+
+static void RTC_API closedCallback(int id, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->connected = false;
+}
+
+static void RTC_API messageCallback(int id, const char *message, int size, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	if (size < 0) { // negative size indicates a null-terminated string
+		printf("Message %d: %s\n", peer == peer1 ? 1 : 2, message);
+	} else {
+		printf("Message %d: [binary of size %d]\n", peer == peer1 ? 1 : 2, size);
+	}
+}
+
+static void RTC_API dataChannelCallback(int pc, int dc, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+
+	char label[256];
+	if (rtcGetDataChannelLabel(dc, label, 256) < 0) {
+		fprintf(stderr, "rtcGetDataChannelLabel failed\n");
+		return;
+	}
+
+	char protocol[256];
+	if (rtcGetDataChannelProtocol(dc, protocol, 256) < 0) {
+		fprintf(stderr, "rtcGetDataChannelProtocol failed\n");
+		return;
+	}
+
+	rtcReliability reliability;
+	if (rtcGetDataChannelReliability(dc, &reliability) < 0) {
+		fprintf(stderr, "rtcGetDataChannelReliability failed\n");
+		return;
+	}
+
+	printf("DataChannel %d: Received with label \"%s\" and protocol \"%s\"\n",
+	       peer == peer1 ? 1 : 2, label, protocol);
+
+	if (strcmp(label, "test") != 0) {
+		fprintf(stderr, "Wrong DataChannel label\n");
+		return;
+	}
+
+	if (strcmp(protocol, "protocol") != 0) {
+		fprintf(stderr, "Wrong DataChannel protocol\n");
+		return;
+	}
+
+	if (reliability.unordered == false) {
+		fprintf(stderr, "Wrong DataChannel reliability\n");
+		return;
+	}
+
+	rtcSetClosedCallback(dc, closedCallback);
+	rtcSetMessageCallback(dc, messageCallback);
+
+	peer->dc = dc;
+	peer->connected = true;
+
+	const char *message = peer == peer1 ? "Hello from 1" : "Hello from 2";
+	rtcSendMessage(peer->dc, message, -1); // negative size indicates a null-terminated string
+}
+
+static Peer *createPeer(const rtcConfiguration *config) {
+	Peer *peer = (Peer *)malloc(sizeof(Peer));
+	if (!peer)
+		return nullptr;
+	memset(peer, 0, sizeof(Peer));
+
+	// Create peer connection
+	peer->pc = rtcCreatePeerConnection(config);
+	rtcSetUserPointer(peer->pc, peer);
+	rtcSetDataChannelCallback(peer->pc, dataChannelCallback);
+	rtcSetLocalDescriptionCallback(peer->pc, descriptionCallback);
+	rtcSetLocalCandidateCallback(peer->pc, candidateCallback);
+	rtcSetStateChangeCallback(peer->pc, stateChangeCallback);
+	rtcSetGatheringStateChangeCallback(peer->pc, gatheringStateCallback);
+
+	return peer;
+}
+
+static void deletePeer(Peer *peer) {
+	if (peer) {
+		if (peer->dc)
+			rtcDeleteDataChannel(peer->dc);
+		if (peer->pc)
+			rtcDeletePeerConnection(peer->pc);
+		free(peer);
+	}
+}
+
+int test_capi_connectivity_main() {
+	int attempts;
+
+	rtcInitLogger(RTC_LOG_DEBUG, nullptr);
+
+	// Create peer 1
+	rtcConfiguration config1;
+	memset(&config1, 0, sizeof(config1));
+	// STUN server example
+	// const char *iceServers[1] = {"stun:stun.l.google.com:19302"};
+	// config1.iceServers = iceServers;
+	// config1.iceServersCount = 1;
+
+	peer1 = createPeer(&config1);
+	if (!peer1)
+		goto error;
+
+	// Create peer 2
+	rtcConfiguration config2;
+	memset(&config2, 0, sizeof(config2));
+	// STUN server example
+	// config2.iceServers = iceServers;
+	// config2.iceServersCount = 1;
+	// Port range example
+	config2.portRangeBegin = 5000;
+	config2.portRangeEnd = 6000;
+
+	peer2 = createPeer(&config2);
+	if (!peer2)
+		goto error;
+
+	// Peer 1: Create data channel
+	rtcDataChannelInit init;
+	memset(&init, 0, sizeof(init));
+	init.protocol = "protocol";
+	init.reliability.unordered = true;
+
+	peer1->dc = rtcCreateDataChannelEx(peer1->pc, "test", &init);
+	rtcSetOpenCallback(peer1->dc, openCallback);
+	rtcSetClosedCallback(peer1->dc, closedCallback);
+	rtcSetMessageCallback(peer1->dc, messageCallback);
+
+	attempts = 10;
+	while ((!peer2->connected || !peer1->connected) && attempts--)
+		sleep(1);
+
+	if (peer1->state != RTC_CONNECTED || peer2->state != RTC_CONNECTED) {
+		fprintf(stderr, "PeerConnection is not connected\n");
+		goto error;
+	}
+
+	if (peer1->signalingState != RTC_SIGNALING_STABLE ||
+	    peer2->signalingState != RTC_SIGNALING_STABLE) {
+		fprintf(stderr, "Signaling state is not stable\n");
+		goto error;
+	}
+
+	if (!peer1->connected || !peer2->connected) {
+		fprintf(stderr, "DataChannel is not connected\n");
+		goto error;
+	}
+
+	char buffer[BUFFER_SIZE];
+	char buffer2[BUFFER_SIZE];
+
+	if (rtcGetLocalDescription(peer1->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetLocalDescription failed\n");
+		goto error;
+	}
+	printf("Local description 1:  %s\n", buffer);
+
+	if (rtcGetRemoteDescription(peer1->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetRemoteDescription failed\n");
+		goto error;
+	}
+	printf("Remote description 1:  %s\n", buffer);
+
+	if (rtcGetLocalDescription(peer2->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetLocalDescription failed\n");
+		goto error;
+	}
+	printf("Local description 2:  %s\n", buffer);
+
+	if (rtcGetRemoteDescription(peer2->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetRemoteDescription failed\n");
+		goto error;
+	}
+	printf("Remote description 2:  %s\n", buffer);
+
+	if (rtcGetLocalAddress(peer1->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetLocalAddress failed\n");
+		goto error;
+	}
+	printf("Local address 1:  %s\n", buffer);
+
+	if (rtcGetRemoteAddress(peer1->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetRemoteAddress failed\n");
+		goto error;
+	}
+	printf("Remote address 1: %s\n", buffer);
+
+	if (rtcGetLocalAddress(peer2->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetLocalAddress failed\n");
+		goto error;
+	}
+	printf("Local address 2:  %s\n", buffer);
+
+	if (rtcGetRemoteAddress(peer2->pc, buffer, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetRemoteAddress failed\n");
+		goto error;
+	}
+	printf("Remote address 2: %s\n", buffer);
+
+	if (rtcGetSelectedCandidatePair(peer1->pc, buffer, BUFFER_SIZE, buffer2, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetSelectedCandidatePair failed\n");
+		goto error;
+	}
+	printf("Local candidate 1:  %s\n", buffer);
+	printf("Remote candidate 1: %s\n", buffer2);
+
+	if (rtcGetSelectedCandidatePair(peer2->pc, buffer, BUFFER_SIZE, buffer2, BUFFER_SIZE) < 0) {
+		fprintf(stderr, "rtcGetSelectedCandidatePair failed\n");
+		goto error;
+	}
+	printf("Local candidate 2:  %s\n", buffer);
+	printf("Remote candidate 2: %s\n", buffer2);
+
+	deletePeer(peer1);
+	sleep(1);
+	deletePeer(peer2);
+	sleep(1);
+
+	// You may call rtcCleanup() when finished to free static resources
+	rtcCleanup();
+	sleep(1);
+
+	printf("Success\n");
+	return 0;
+
+error:
+	deletePeer(peer1);
+	deletePeer(peer2);
+	return -1;
+}
+
+#include <stdexcept>
+
+void test_capi_connectivity() {
+	if (test_capi_connectivity_main())
+		throw std::runtime_error("Connection failed");
+}

test/capi_track.cpp

@@ -33,75 +33,62 @@ typedef struct {
 	rtcState state;
 	rtcGatheringState gatheringState;
 	int pc;
-	int dc;
+	int tr;
 	bool connected;
 } Peer;
 
-Peer *peer1 = NULL;
-Peer *peer2 = NULL;
+static Peer *peer1 = NULL;
+static Peer *peer2 = NULL;
 
-static void descriptionCallback(const char *sdp, const char *type, void *ptr) {
+static const char *mediaDescription = "video 9 UDP/TLS/RTP/SAVPF\r\n"
+                                      "a=mid:video\r\n";
+
+static void RTC_API descriptionCallback(int pc, const char *sdp, const char *type, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	printf("Description %d:\n%s\n", peer == peer1 ? 1 : 2, sdp);
 	Peer *other = peer == peer1 ? peer2 : peer1;
 	rtcSetRemoteDescription(other->pc, sdp, type);
 }
 
-static void candidateCallback(const char *cand, const char *mid, void *ptr) {
+static void RTC_API candidateCallback(int pc, const char *cand, const char *mid, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	printf("Candidate %d: %s\n", peer == peer1 ? 1 : 2, cand);
 	Peer *other = peer == peer1 ? peer2 : peer1;
 	rtcAddRemoteCandidate(other->pc, cand, mid);
 }
 
-static void stateChangeCallback(rtcState state, void *ptr) {
+static void RTC_API stateChangeCallback(int pc, rtcState state, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->state = state;
 	printf("State %d: %d\n", peer == peer1 ? 1 : 2, (int)state);
 }
 
-static void gatheringStateCallback(rtcGatheringState state, void *ptr) {
+static void RTC_API gatheringStateCallback(int pc, rtcGatheringState state, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->gatheringState = state;
 	printf("Gathering state %d: %d\n", peer == peer1 ? 1 : 2, (int)state);
 }
 
-static void openCallback(void *ptr) {
+static void RTC_API openCallback(int id, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->connected = true;
-	printf("DataChannel %d: Open\n", peer == peer1 ? 1 : 2);
-
-	const char *message = peer == peer1 ? "Hello from 1" : "Hello from 2";
-	rtcSendMessage(peer->dc, message, -1); // negative size indicates a null-terminated string
+	printf("Track %d: Open\n", peer == peer1 ? 1 : 2);
 }
 
-static void closedCallback(void *ptr) {
+static void RTC_API closedCallback(int id, void *ptr) {
 	Peer *peer = (Peer *)ptr;
 	peer->connected = false;
 }
 
-static void messageCallback(const char *message, int size, void *ptr) {
+static void RTC_API trackCallback(int pc, int tr, void *ptr) {
 	Peer *peer = (Peer *)ptr;
-	if (size < 0) { // negative size indicates a null-terminated string
-		printf("Message %d: %s\n", peer == peer1 ? 1 : 2, message);
-	} else {
-		printf("Message %d: [binary of size %d]\n", peer == peer1 ? 1 : 2, size);
-	}
-}
-
-static void dataChannelCallback(int dc, void *ptr) {
-	Peer *peer = (Peer *)ptr;
-	peer->dc = dc;
+	peer->tr = tr;
 	peer->connected = true;
-	rtcSetClosedCallback(dc, closedCallback);
-	rtcSetMessageCallback(dc, messageCallback);
+	rtcSetClosedCallback(tr, closedCallback);
 
-	char buffer[256];
-	if (rtcGetDataChannelLabel(dc, buffer, 256) >= 0)
-		printf("DataChannel %d: Received with label \"%s\"\n", peer == peer1 ? 1 : 2, buffer);
-
-	const char *message = peer == peer1 ? "Hello from 1" : "Hello from 2";
-	rtcSendMessage(peer->dc, message, -1); // negative size indicates a null-terminated string
+	char buffer[1024];
+	if (rtcGetTrackDescription(tr, buffer, 1024) >= 0)
+		printf("Track %d: Received with media description: \n%s\n", peer == peer1 ? 1 : 2, buffer);
 }
 
 static Peer *createPeer(const rtcConfiguration *config) {
@@ -113,7 +100,7 @@ static Peer *createPeer(const rtcConfiguration *config) {
 	// Create peer connection
 	peer->pc = rtcCreatePeerConnection(config);
 	rtcSetUserPointer(peer->pc, peer);
-	rtcSetDataChannelCallback(peer->pc, dataChannelCallback);
+	rtcSetTrackCallback(peer->pc, trackCallback);
 	rtcSetLocalDescriptionCallback(peer->pc, descriptionCallback);
 	rtcSetLocalCandidateCallback(peer->pc, candidateCallback);
 	rtcSetStateChangeCallback(peer->pc, stateChangeCallback);
@@ -124,15 +111,15 @@ static Peer *createPeer(const rtcConfiguration *config) {
 
 static void deletePeer(Peer *peer) {
 	if (peer) {
-		if (peer->dc)
-			rtcDeleteDataChannel(peer->dc);
+		if (peer->tr)
+			rtcDeleteTrack(peer->tr);
 		if (peer->pc)
 			rtcDeletePeerConnection(peer->pc);
 		free(peer);
 	}
 }
 
-int test_capi_main() {
+int test_capi_track_main() {
 	int attempts;
 
 	rtcInitLogger(RTC_LOG_DEBUG, nullptr);
@@ -163,14 +150,16 @@ int test_capi_main() {
 	if (!peer2)
 		goto error;
 
-	// Peer 1: Create data channel
-	peer1->dc = rtcCreateDataChannel(peer1->pc, "test");
-	rtcSetOpenCallback(peer1->dc, openCallback);
-	rtcSetClosedCallback(peer1->dc, closedCallback);
-	rtcSetMessageCallback(peer1->dc, messageCallback);
+	// Peer 1: Create track
+	peer1->tr = rtcAddTrack(peer1->pc, mediaDescription);
+	rtcSetOpenCallback(peer1->tr, openCallback);
+	rtcSetClosedCallback(peer1->tr, closedCallback);
+
+	// Initiate the handshake
+	rtcSetLocalDescription(peer1->pc, NULL);
 
 	attempts = 10;
-	while (!peer2->connected && !peer1->connected && attempts--)
+	while ((!peer2->connected || !peer1->connected) && attempts--)
 		sleep(1);
 
 	if (peer1->state != RTC_CONNECTED || peer2->state != RTC_CONNECTED) {
@@ -179,20 +168,10 @@ int test_capi_main() {
 	}
 
 	if (!peer1->connected || !peer2->connected) {
-		fprintf(stderr, "DataChannel is not connected\n");
+		fprintf(stderr, "Track is not connected\n");
 		goto error;
 	}
 
-	char buffer[256];
-	if (rtcGetLocalAddress(peer1->pc, buffer, 256) >= 0)
-		printf("Local address 1:  %s\n", buffer);
-	if (rtcGetRemoteAddress(peer1->pc, buffer, 256) >= 0)
-		printf("Remote address 1: %s\n", buffer);
-	if (rtcGetLocalAddress(peer2->pc, buffer, 256) >= 0)
-		printf("Local address 2:  %s\n", buffer);
-	if (rtcGetRemoteAddress(peer2->pc, buffer, 256) >= 0)
-		printf("Remote address 2: %s\n", buffer);
-
 	deletePeer(peer1);
 	sleep(1);
 	deletePeer(peer2);
@@ -200,7 +179,7 @@ int test_capi_main() {
 
 	// You may call rtcCleanup() when finished to free static resources
 	rtcCleanup();
-	sleep(2);
+	sleep(1);
 
 	printf("Success\n");
 	return 0;
@@ -213,7 +192,7 @@ error:
 
 #include <stdexcept>
 
-void test_capi() {
-	if (test_capi_main())
+void test_capi_track() {
+	if (test_capi_track_main())
 		throw std::runtime_error("Connection failed");
 }

test/connectivity.cpp

@@ -47,20 +47,20 @@ void test_connectivity() {
 
 	auto pc2 = std::make_shared<PeerConnection>(config2);
 
-	pc1->onLocalDescription([wpc2 = make_weak_ptr(pc2)](const Description &sdp) {
+	pc1->onLocalDescription([wpc2 = make_weak_ptr(pc2)](Description sdp) {
 		auto pc2 = wpc2.lock();
 		if (!pc2)
 			return;
 		cout << "Description 1: " << sdp << endl;
-		pc2->setRemoteDescription(sdp);
+		pc2->setRemoteDescription(string(sdp));
 	});
 
-	pc1->onLocalCandidate([wpc2 = make_weak_ptr(pc2)](const Candidate &candidate) {
+	pc1->onLocalCandidate([wpc2 = make_weak_ptr(pc2)](Candidate candidate) {
 		auto pc2 = wpc2.lock();
 		if (!pc2)
 			return;
 		cout << "Candidate 1: " << candidate << endl;
-		pc2->addRemoteCandidate(candidate);
+		pc2->addRemoteCandidate(string(candidate));
 	});
 
 	pc1->onStateChange([](PeerConnection::State state) { cout << "State 1: " << state << endl; });
@@ -69,20 +69,24 @@ void test_connectivity() {
 		cout << "Gathering state 1: " << state << endl;
 	});
 
-	pc2->onLocalDescription([wpc1 = make_weak_ptr(pc1)](const Description &sdp) {
+	pc1->onSignalingStateChange([](PeerConnection::SignalingState state) {
+		cout << "Signaling state 1: " << state << endl;
+	});
+
+	pc2->onLocalDescription([wpc1 = make_weak_ptr(pc1)](Description sdp) {
 		auto pc1 = wpc1.lock();
 		if (!pc1)
 			return;
 		cout << "Description 2: " << sdp << endl;
-		pc1->setRemoteDescription(sdp);
+		pc1->setRemoteDescription(string(sdp));
 	});
 
-	pc2->onLocalCandidate([wpc1 = make_weak_ptr(pc1)](const Candidate &candidate) {
+	pc2->onLocalCandidate([wpc1 = make_weak_ptr(pc1)](Candidate candidate) {
 		auto pc1 = wpc1.lock();
 		if (!pc1)
 			return;
 		cout << "Candidate 2: " << candidate << endl;
-		pc1->addRemoteCandidate(candidate);
+		pc1->addRemoteCandidate(string(candidate));
 	});
 
 	pc2->onStateChange([](PeerConnection::State state) { cout << "State 2: " << state << endl; });
@@ -91,11 +95,19 @@ void test_connectivity() {
 		cout << "Gathering state 2: " << state << endl;
 	});
 
+	pc2->onSignalingStateChange([](PeerConnection::SignalingState state) {
+		cout << "Signaling state 2: " << state << endl;
+	});
+
 	shared_ptr<DataChannel> dc2;
 	pc2->onDataChannel([&dc2](shared_ptr<DataChannel> dc) {
 		cout << "DataChannel 2: Received with label \"" << dc->label() << "\"" << endl;
+		if (dc->label() != "test") {
+			cerr << "Wrong DataChannel label" << endl;
+			return;
+		}
 
-		dc->onMessage([](const variant<binary, string> &message) {
+		dc->onMessage([](variant<binary, string> message) {
 			if (holds_alternative<string>(message)) {
 				cout << "Message 2: " << get<string>(message) << endl;
 			}
@@ -121,6 +133,7 @@ void test_connectivity() {
 		}
 	});
 
+	// Wait a bit
 	int attempts = 10;
 	shared_ptr<DataChannel> adc2;
 	while ((!(adc2 = std::atomic_load(&dc2)) || !adc2->isOpen() || !dc1->isOpen()) && attempts--)
@@ -142,6 +155,90 @@ void test_connectivity() {
 	if (auto addr = pc2->remoteAddress())
 		cout << "Remote address 2: " << *addr << endl;
 
+	Candidate local, remote;
+	if (pc1->getSelectedCandidatePair(&local, &remote)) {
+		cout << "Local candidate 1:  " << local << endl;
+		cout << "Remote candidate 1: " << remote << endl;
+	}
+	if (pc2->getSelectedCandidatePair(&local, &remote)) {
+		cout << "Local candidate 2:  " << local << endl;
+		cout << "Remote candidate 2: " << remote << endl;
+	}
+
+	// Try to open a second data channel with another label
+	shared_ptr<DataChannel> second2;
+	pc2->onDataChannel([&second2](shared_ptr<DataChannel> dc) {
+		cout << "Second DataChannel 2: Received with label \"" << dc->label() << "\"" << endl;
+		if (dc->label() != "second") {
+			cerr << "Wrong second DataChannel label" << endl;
+			return;
+		}
+
+		dc->onMessage([](variant<binary, string> message) {
+			if (holds_alternative<string>(message)) {
+				cout << "Second Message 2: " << get<string>(message) << endl;
+			}
+		});
+
+		dc->send("Send hello from 2");
+
+		std::atomic_store(&second2, dc);
+	});
+
+	auto second1 = pc1->createDataChannel("second");
+	second1->onOpen([wsecond1 = make_weak_ptr(dc1)]() {
+		auto second1 = wsecond1.lock();
+		if (!second1)
+			return;
+
+		cout << "Second DataChannel 1: Open" << endl;
+		second1->send("Second hello from 1");
+	});
+	dc1->onMessage([](const variant<binary, string> &message) {
+		if (holds_alternative<string>(message)) {
+			cout << "Second Message 1: " << get<string>(message) << endl;
+		}
+	});
+
+	// Wait a bit
+	attempts = 10;
+	shared_ptr<DataChannel> asecond2;
+	while (
+	    (!(asecond2 = std::atomic_load(&second2)) || !asecond2->isOpen() || !second1->isOpen()) &&
+	    attempts--)
+		this_thread::sleep_for(1s);
+
+	if (!asecond2 || !asecond2->isOpen() || !second1->isOpen())
+		throw runtime_error("Second DataChannel is not open");
+
+	// Try to open a negotiated channel
+	DataChannelInit init;
+	init.negotiated = true;
+	init.id = 42;
+	auto negotiated1 = pc1->createDataChannel("negotiated", init);
+	auto negotiated2 = pc2->createDataChannel("negoctated", init);
+
+	if (!negotiated1->isOpen() || !negotiated2->isOpen())
+		throw runtime_error("Negociated DataChannel is not open");
+
+	std::atomic<bool> received = false;
+	negotiated2->onMessage([&received](const variant<binary, string> &message) {
+		if (holds_alternative<string>(message)) {
+			cout << "Second Message 2: " << get<string>(message) << endl;
+			received = true;
+		}
+	});
+
+	negotiated1->send("Hello from negotiated channel");
+
+	// Wait a bit
+	attempts = 5;
+	while (!received && attempts--)
+		this_thread::sleep_for(1s);
+
+	if (!received)
+		throw runtime_error("Negociated DataChannel failed");
+
 	// Delay close of peer 2 to check closing works properly
 	pc1->close();
 	this_thread::sleep_for(1s);
@@ -150,7 +247,7 @@ void test_connectivity() {
 
 	// You may call rtc::Cleanup() when finished to free static resources
 	rtc::Cleanup();
-	this_thread::sleep_for(2s);
+	this_thread::sleep_for(1s);
 
 	cout << "Success" << endl;
 }

test/main.cpp

@@ -24,7 +24,9 @@ using namespace std;
 using namespace chrono_literals;
 
 void test_connectivity();
-void test_capi();
+void test_track();
+void test_capi_connectivity();
+void test_capi_track();
 void test_websocket();
 size_t benchmark(chrono::milliseconds duration);
 
@@ -48,15 +50,36 @@ int main(int argc, char **argv) {
 		cerr << "WebRTC connectivity test failed: " << e.what() << endl;
 		return -1;
 	}
+	this_thread::sleep_for(1s);
 	try {
-		cout << endl << "*** Running WebRTC C API test..." << endl;
-		test_capi();
-		cout << "*** Finished WebRTC C API test" << endl;
+		cout << endl << "*** Running WebRTC C API connectivity test..." << endl;
+		test_capi_connectivity();
+		cout << "*** Finished WebRTC C API connectivity test" << endl;
 	} catch (const exception &e) {
-		cerr << "WebRTC C API test failed: " << e.what() << endl;
+		cerr << "WebRTC C API connectivity test failed: " << e.what() << endl;
 		return -1;
 	}
+#if RTC_ENABLE_MEDIA
+	this_thread::sleep_for(1s);
+	try {
+		cout << endl << "*** Running WebRTC Track test..." << endl;
+		test_track();
+		cout << "*** Finished WebRTC Track test" << endl;
+	} catch (const exception &e) {
+		cerr << "WebRTC Track test failed: " << e.what() << endl;
+		return -1;
+	}
+	try {
+		cout << endl << "*** Running WebRTC C API track test..." << endl;
+		test_capi_track();
+		cout << "*** Finished WebRTC C API track test" << endl;
+	} catch (const exception &e) {
+		cerr << "WebRTC C API track test failed: " << e.what() << endl;
+		return -1;
+	}
+#endif
 #if RTC_ENABLE_WEBSOCKET
+	this_thread::sleep_for(1s);
 	try {
 		cout << endl << "*** Running WebSocket test..." << endl;
 		test_websocket();
@@ -66,6 +89,7 @@ int main(int argc, char **argv) {
 		return -1;
 	}
 #endif
+	this_thread::sleep_for(1s);
 	try {
 		cout << endl << "*** Running WebRTC benchmark..." << endl;
 		test_benchmark();

test/track.cpp

@@ -0,0 +1,151 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rtc/rtc.hpp"
+
+#include <atomic>
+#include <chrono>
+#include <iostream>
+#include <memory>
+#include <thread>
+
+using namespace rtc;
+using namespace std;
+
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+void test_track() {
+	InitLogger(LogLevel::Debug);
+
+	Configuration config1;
+	// STUN server example
+	// config1.iceServers.emplace_back("stun:stun.l.google.com:19302");
+
+	auto pc1 = std::make_shared<PeerConnection>(config1);
+
+	Configuration config2;
+	// STUN server example
+	// config2.iceServers.emplace_back("stun:stun.l.google.com:19302");
+	// Port range example
+	config2.portRangeBegin = 5000;
+	config2.portRangeEnd = 6000;
+
+	auto pc2 = std::make_shared<PeerConnection>(config2);
+
+	pc1->onLocalDescription([wpc2 = make_weak_ptr(pc2)](Description sdp) {
+		auto pc2 = wpc2.lock();
+		if (!pc2)
+			return;
+		cout << "Description 1: " << sdp << endl;
+		pc2->setRemoteDescription(string(sdp));
+	});
+
+	pc1->onLocalCandidate([wpc2 = make_weak_ptr(pc2)](Candidate candidate) {
+		auto pc2 = wpc2.lock();
+		if (!pc2)
+			return;
+		cout << "Candidate 1: " << candidate << endl;
+		pc2->addRemoteCandidate(string(candidate));
+	});
+
+	pc1->onStateChange([](PeerConnection::State state) { cout << "State 1: " << state << endl; });
+
+	pc1->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "Gathering state 1: " << state << endl;
+	});
+
+	pc2->onLocalDescription([wpc1 = make_weak_ptr(pc1)](Description sdp) {
+		auto pc1 = wpc1.lock();
+		if (!pc1)
+			return;
+		cout << "Description 2: " << sdp << endl;
+		pc1->setRemoteDescription(string(sdp));
+	});
+
+	pc2->onLocalCandidate([wpc1 = make_weak_ptr(pc1)](Candidate candidate) {
+		auto pc1 = wpc1.lock();
+		if (!pc1)
+			return;
+		cout << "Candidate 2: " << candidate << endl;
+		pc1->addRemoteCandidate(string(candidate));
+	});
+
+	pc2->onStateChange([](PeerConnection::State state) { cout << "State 2: " << state << endl; });
+
+	pc2->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "Gathering state 2: " << state << endl;
+	});
+
+	shared_ptr<Track> t2;
+	string newTrackMid;
+	pc2->onTrack([&t2, &newTrackMid](shared_ptr<Track> t) {
+		cout << "Track 2: Received with mid \"" << t->mid() << "\"" << endl;
+		if (t->mid() != newTrackMid) {
+			cerr << "Wrong track mid" << endl;
+			return;
+		}
+
+		std::atomic_store(&t2, t);
+	});
+
+	// Test opening a track
+	newTrackMid = "test";
+	auto t1 = pc1->addTrack(Description::Video(newTrackMid));
+
+	pc1->setLocalDescription();
+
+	int attempts = 10;
+	shared_ptr<Track> at2;
+	while ((!(at2 = std::atomic_load(&t2)) || !at2->isOpen() || !t1->isOpen()) && attempts--)
+		this_thread::sleep_for(1s);
+
+	if (pc1->state() != PeerConnection::State::Connected &&
+	    pc2->state() != PeerConnection::State::Connected)
+		throw runtime_error("PeerConnection is not connected");
+
+	if (!at2 || !at2->isOpen() || !t1->isOpen())
+		throw runtime_error("Track is not open");
+
+	// Test renegotiation
+	newTrackMid = "added";
+	t1 = pc1->addTrack(Description::Video(newTrackMid));
+
+	pc1->setLocalDescription();
+
+	attempts = 10;
+	t2.reset();
+	while ((!(at2 = std::atomic_load(&t2)) || !at2->isOpen() || !t1->isOpen()) && attempts--)
+		this_thread::sleep_for(1s);
+
+	if (!at2 || !at2->isOpen() || !t1->isOpen())
+		throw runtime_error("Renegotiated track is not open");
+
+	// TODO: Test sending RTP packets in track
+
+	// Delay close of peer 2 to check closing works properly
+	pc1->close();
+	this_thread::sleep_for(1s);
+	pc2->close();
+	this_thread::sleep_for(1s);
+
+	// You may call rtc::Cleanup() when finished to free static resources
+	rtc::Cleanup();
+	this_thread::sleep_for(1s);
+
+	cout << "Success" << endl;
+}

test/websocket.cpp

@@ -20,11 +20,11 @@
 
 #if RTC_ENABLE_WEBSOCKET
 
+#include <atomic>
 #include <chrono>
 #include <iostream>
 #include <memory>
 #include <thread>
-#include <atomic>
 
 using namespace rtc;
 using namespace std;
@@ -53,17 +53,17 @@ void test_websocket() {
 	ws->onClosed([]() { cout << "WebSocket: Closed" << endl; });
 
 	std::atomic<bool> received = false;
-	ws->onMessage([&received, &myMessage](const variant<binary, string> &message) {
+	ws->onMessage([&received, &myMessage](variant<binary, string> message) {
 		if (holds_alternative<string>(message)) {
-			string str = get<string>(message);
-			if((received = (str == myMessage)))
+			string str = std::move(get<string>(message));
+			if ((received = (str == myMessage)))
 				cout << "WebSocket: Received expected message" << endl;
 			else
 				cout << "WebSocket: Received UNEXPECTED message" << endl;
 		}
 	});
 
-	ws->open("wss://echo.websocket.org/");
+	ws->open("wss://echo.websocket.org:443/");
 
 	int attempts = 10;
 	while ((!ws->isOpen() || !received) && attempts--)
@@ -72,11 +72,11 @@ void test_websocket() {
 	if (!ws->isOpen())
 		throw runtime_error("WebSocket is not open");
 
-	if(!received)
+	if (!received)
 		throw runtime_error("Expected message not received");
 
 	ws->close();
-	this_thread::sleep_for(2s);
+	this_thread::sleep_for(1s);
 
 	// You may call rtc::Cleanup() when finished to free static resources
 	rtc::Cleanup();
@@ -86,4 +86,3 @@ void test_websocket() {
 }
 
 #endif
-