mirror of
https://github.com/mii443/wasmer.git
synced 2025-12-06 20:58:28 +00:00
1163 lines
41 KiB
Rust
1163 lines
41 KiB
Rust
use crate::exports::{ExportError, Exportable};
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use crate::externals::Extern;
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use crate::store::Store;
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use crate::types::Val;
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use crate::FunctionType;
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use crate::NativeFunc;
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use crate::RuntimeError;
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pub use inner::{FromToNativeWasmType, HostFunction, WasmTypeList, WithEnv, WithoutEnv};
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use std::cell::RefCell;
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use std::cmp::max;
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use wasmer_runtime::{
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raise_user_trap, resume_panic, wasmer_call_trampoline, Export, ExportFunction,
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VMCallerCheckedAnyfunc, VMContext, VMDynamicFunctionContext, VMFunctionBody, VMFunctionKind,
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VMTrampoline,
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};
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/// A function defined in the Wasm module
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#[derive(Clone, PartialEq)]
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pub struct WasmFunctionDefinition {
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// The trampoline to do the call
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pub(crate) trampoline: VMTrampoline,
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}
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/// A function defined in the Host
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#[derive(Clone, PartialEq)]
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pub struct HostFunctionDefinition {
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/// If the host function has a custom environment attached
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pub(crate) has_env: bool,
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}
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/// The inner helper
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#[derive(Clone, PartialEq)]
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pub enum FunctionDefinition {
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/// A function defined in the Wasm side
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Wasm(WasmFunctionDefinition),
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/// A function defined in the Host side
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Host(HostFunctionDefinition),
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}
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/// A WebAssembly `function`.
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#[derive(Clone, PartialEq)]
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pub struct Function {
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pub(crate) store: Store,
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pub(crate) definition: FunctionDefinition,
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// If the Function is owned by the Store, not the instance
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pub(crate) owned_by_store: bool,
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pub(crate) exported: ExportFunction,
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}
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impl Function {
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/// Creates a new `Function` that is:
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///
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/// 1. Static/Monomorphic, i.e. all inputs and outputs have a
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/// unique _statically declared type_. The outputs can be
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/// wrapped in a `Result`.
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/// 2. Independent, i.e. the function _does not_ receive an
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/// environment argument.
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pub fn new<F, Args, Rets, Env>(store: &Store, func: F) -> Self
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where
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F: HostFunction<Args, Rets, WithoutEnv, Env>,
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Args: WasmTypeList,
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Rets: WasmTypeList,
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Env: Sized + 'static,
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{
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let function = inner::Function::<Args, Rets>::new(func);
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let address = function.address() as *const VMFunctionBody;
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let vmctx = std::ptr::null_mut() as *mut _ as *mut VMContext;
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let signature = function.ty();
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Self {
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store: store.clone(),
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owned_by_store: true,
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definition: FunctionDefinition::Host(HostFunctionDefinition { has_env: false }),
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exported: ExportFunction {
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address,
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vmctx,
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signature,
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kind: VMFunctionKind::Static,
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},
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}
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}
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/// Creates a new `Function` that is:
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///
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/// 1. Static/Monomorphic, i.e. all inputs and outputs have a
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/// unique statically declared type. The outputs can be wrapped
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/// in a `Result`.
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/// 2. Dependent, i.e. the function _does_ receive an environment
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/// argument (given by `env`).
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pub fn new_env<F, Args, Rets, Env>(store: &Store, env: Env, func: F) -> Self
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where
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F: HostFunction<Args, Rets, WithEnv, Env>,
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Args: WasmTypeList,
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Rets: WasmTypeList,
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Env: Sized + 'static,
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{
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let function = inner::Function::<Args, Rets>::new(func);
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let address = function.address();
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// TODO: We need to refactor the Function context.
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// Right now is structured as it's always a `VMContext`. However, only
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// Wasm-defined functions have a `VMContext`.
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// In the case of Host-defined functions `VMContext` is whatever environment
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// the user want to attach to the function.
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let box_env = Box::new(env);
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let vmctx = Box::into_raw(box_env) as *mut _ as *mut VMContext;
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let signature = function.ty();
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Self {
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store: store.clone(),
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owned_by_store: true,
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definition: FunctionDefinition::Host(HostFunctionDefinition { has_env: true }),
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exported: ExportFunction {
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address,
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kind: VMFunctionKind::Static,
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vmctx,
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signature,
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},
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}
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}
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/// Creates a new `Function` that is:
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///
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/// 1. Dynamic/Polymorphic, i.e. all inputs are received in a
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/// slice of `Val` (the set of all Wasm values), and all
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/// outputs are stored in a vector of `Val`, wrapped in a
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/// `Result`.
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/// 2. Independent, i.e. the function _does not_ receive an
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/// environment argument.
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#[allow(clippy::cast_ptr_alignment)]
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pub fn new_dynamic<F>(store: &Store, ty: &FunctionType, func: F) -> Self
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where
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F: Fn(&[Val]) -> Result<Vec<Val>, RuntimeError> + 'static,
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{
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let dynamic_ctx = VMDynamicFunctionContext::from_context(VMDynamicFunctionWithoutEnv {
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func: Box::new(func),
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function_type: ty.clone(),
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});
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// We don't yet have the address with the Wasm ABI signature.
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// The engine linker will replace the address with one pointing to a
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// generated dynamic trampoline.
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let address = std::ptr::null() as *const VMFunctionBody;
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let vmctx = Box::into_raw(Box::new(dynamic_ctx)) as *mut VMContext;
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Self {
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store: store.clone(),
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owned_by_store: true,
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definition: FunctionDefinition::Host(HostFunctionDefinition { has_env: false }),
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exported: ExportFunction {
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address,
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kind: VMFunctionKind::Dynamic,
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vmctx,
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signature: ty.clone(),
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},
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}
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}
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/// Creates a new `Function` that is:
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///
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/// 1. Dynamic/Polymorphic, i.e. all inputs are received in a
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/// slice of `Val` (the set of all Wasm values), and all
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/// outputs are stored in a vector of `Val`, wrapped in a
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/// `Result`.
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/// 2. Dependent, i.e. the function _does_ receive an environment
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/// argument (given by `env`).
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#[allow(clippy::cast_ptr_alignment)]
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pub fn new_dynamic_env<F, Env>(store: &Store, ty: &FunctionType, env: Env, func: F) -> Self
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where
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F: Fn(&mut Env, &[Val]) -> Result<Vec<Val>, RuntimeError> + 'static,
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Env: Sized + 'static,
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{
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let dynamic_ctx = VMDynamicFunctionContext::from_context(VMDynamicFunctionWithEnv {
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env: RefCell::new(env),
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func: Box::new(func),
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function_type: ty.clone(),
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});
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// We don't yet have the address with the Wasm ABI signature.
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// The engine linker will replace the address with one pointing to a
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// generated dynamic trampoline.
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let address = std::ptr::null() as *const VMFunctionBody;
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let vmctx = Box::into_raw(Box::new(dynamic_ctx)) as *mut VMContext;
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Self {
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store: store.clone(),
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owned_by_store: true,
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definition: FunctionDefinition::Host(HostFunctionDefinition { has_env: true }),
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exported: ExportFunction {
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address,
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kind: VMFunctionKind::Dynamic,
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vmctx,
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signature: ty.clone(),
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},
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}
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}
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/// Returns the underlying type of this function.
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pub fn ty(&self) -> &FunctionType {
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&self.exported.signature
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}
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pub fn store(&self) -> &Store {
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&self.store
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}
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fn call_wasm(
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&self,
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func: &WasmFunctionDefinition,
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params: &[Val],
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results: &mut [Val],
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) -> Result<(), RuntimeError> {
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let format_types_for_error_message = |items: &[Val]| {
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items
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.iter()
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.map(|param| param.ty().to_string())
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.collect::<Vec<String>>()
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.join(", ")
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};
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let signature = self.ty();
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if signature.params().len() != params.len() {
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return Err(RuntimeError::new(format!(
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"Parameters of type [{}] did not match signature {}",
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format_types_for_error_message(params),
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&signature
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)));
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}
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if signature.results().len() != results.len() {
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return Err(RuntimeError::new(format!(
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"Results of type [{}] did not match signature {}",
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format_types_for_error_message(results),
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&signature,
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)));
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}
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let mut values_vec = vec![0; max(params.len(), results.len())];
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// Store the argument values into `values_vec`.
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let param_tys = signature.params().iter();
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for ((arg, slot), ty) in params.iter().zip(&mut values_vec).zip(param_tys) {
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if arg.ty() != *ty {
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let param_types = format_types_for_error_message(params);
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return Err(RuntimeError::new(format!(
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"Parameters of type [{}] did not match signature {}",
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param_types, &signature,
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)));
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}
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unsafe {
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arg.write_value_to(slot);
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}
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}
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// Call the trampoline.
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if let Err(error) = unsafe {
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wasmer_call_trampoline(
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self.exported.vmctx,
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func.trampoline,
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self.exported.address,
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values_vec.as_mut_ptr() as *mut u8,
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)
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} {
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return Err(RuntimeError::from_trap(error));
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}
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// Load the return values out of `values_vec`.
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for (index, &value_type) in signature.results().iter().enumerate() {
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unsafe {
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let ptr = values_vec.as_ptr().add(index);
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results[index] = Val::read_value_from(ptr, value_type);
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}
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}
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Ok(())
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}
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/// Returns the number of parameters that this function takes.
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pub fn param_arity(&self) -> usize {
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self.ty().params().len()
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}
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/// Returns the number of results this function produces.
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pub fn result_arity(&self) -> usize {
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self.ty().results().len()
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}
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/// Call the [`Function`] function.
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///
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/// Depending on where the Function is defined, it will call it.
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/// 1. If the function is defined inside a WebAssembly, it will call the trampoline
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/// for the function signature.
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/// 2. If the function is defined in the host (in a native way), it will
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/// call the trampoline.
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pub fn call(&self, params: &[Val]) -> Result<Box<[Val]>, RuntimeError> {
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let mut results = vec![Val::null(); self.result_arity()];
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match &self.definition {
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FunctionDefinition::Wasm(wasm) => {
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self.call_wasm(&wasm, params, &mut results)?;
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}
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_ => unimplemented!("The function definition isn't supported for the moment"),
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}
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Ok(results.into_boxed_slice())
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}
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pub(crate) fn from_export(store: &Store, wasmer_export: ExportFunction) -> Self {
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let vmsignature = store.engine().register_signature(&wasmer_export.signature);
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let trampoline = store
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.engine()
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.function_call_trampoline(vmsignature)
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.expect("Can't get call trampoline for the function");
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Self {
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store: store.clone(),
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owned_by_store: false,
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definition: FunctionDefinition::Wasm(WasmFunctionDefinition { trampoline }),
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exported: wasmer_export,
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}
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}
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pub(crate) fn checked_anyfunc(&self) -> VMCallerCheckedAnyfunc {
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let vmsignature = self
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.store
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.engine()
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.register_signature(&self.exported.signature);
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VMCallerCheckedAnyfunc {
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func_ptr: self.exported.address,
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type_index: vmsignature,
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vmctx: self.exported.vmctx,
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}
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}
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/// Transform this WebAssembly function into a function with the
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/// native ABI. See `NativeFunc` to learn more.
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pub fn native<'a, Args, Rets>(&self) -> Result<NativeFunc<'a, Args, Rets>, RuntimeError>
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where
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Args: WasmTypeList,
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Rets: WasmTypeList,
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{
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// type check
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{
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let expected = self.exported.signature.params();
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let given = Args::wasm_types();
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if expected != given {
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return Err(RuntimeError::new(format!(
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"given types (`{:?}`) for the function arguments don't match the actual types (`{:?}`)",
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given,
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expected,
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)));
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}
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}
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{
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let expected = self.exported.signature.results();
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let given = Rets::wasm_types();
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if expected != given {
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// todo: error result types don't match
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return Err(RuntimeError::new(format!(
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"given types (`{:?}`) for the function results don't match the actual types (`{:?}`)",
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given,
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expected,
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)));
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}
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}
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Ok(NativeFunc::new(
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self.store.clone(),
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self.exported.address,
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self.exported.vmctx,
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self.exported.kind,
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self.definition.clone(),
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))
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}
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}
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impl<'a> Exportable<'a> for Function {
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fn to_export(&self) -> Export {
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self.exported.clone().into()
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}
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fn get_self_from_extern(_extern: &'a Extern) -> Result<&'a Self, ExportError> {
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match _extern {
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Extern::Function(func) => Ok(func),
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_ => Err(ExportError::IncompatibleType),
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}
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}
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}
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impl std::fmt::Debug for Function {
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fn fmt(&self, _f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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Ok(())
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}
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}
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/// This trait is one that all dynamic functions must fulfill.
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pub(crate) trait VMDynamicFunction {
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fn call(&self, args: &[Val]) -> Result<Vec<Val>, RuntimeError>;
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fn function_type(&self) -> &FunctionType;
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}
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pub(crate) struct VMDynamicFunctionWithoutEnv {
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#[allow(clippy::type_complexity)]
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func: Box<dyn Fn(&[Val]) -> Result<Vec<Val>, RuntimeError> + 'static>,
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function_type: FunctionType,
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}
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impl VMDynamicFunction for VMDynamicFunctionWithoutEnv {
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fn call(&self, args: &[Val]) -> Result<Vec<Val>, RuntimeError> {
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(*self.func)(&args)
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}
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fn function_type(&self) -> &FunctionType {
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&self.function_type
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}
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}
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|
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pub(crate) struct VMDynamicFunctionWithEnv<Env>
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where
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Env: Sized + 'static,
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{
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function_type: FunctionType,
|
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#[allow(clippy::type_complexity)]
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func: Box<dyn Fn(&mut Env, &[Val]) -> Result<Vec<Val>, RuntimeError> + 'static>,
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env: RefCell<Env>,
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}
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|
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impl<Env> VMDynamicFunction for VMDynamicFunctionWithEnv<Env>
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where
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Env: Sized + 'static,
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{
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fn call(&self, args: &[Val]) -> Result<Vec<Val>, RuntimeError> {
|
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// TODO: the `&mut *self.env.as_ptr()` is likely invoking some "mild"
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// undefined behavior due to how it's used in the static fn call
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unsafe { (*self.func)(&mut *self.env.as_ptr(), &args) }
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}
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fn function_type(&self) -> &FunctionType {
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&self.function_type
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}
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}
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|
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trait VMDynamicFunctionCall<T: VMDynamicFunction> {
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fn from_context(ctx: T) -> Self;
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fn address_ptr() -> *const VMFunctionBody;
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unsafe fn func_wrapper(&self, values_vec: *mut i128);
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}
|
|
|
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impl<T: VMDynamicFunction> VMDynamicFunctionCall<T> for VMDynamicFunctionContext<T> {
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fn from_context(ctx: T) -> Self {
|
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Self {
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address: Self::address_ptr(),
|
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ctx,
|
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}
|
|
}
|
|
|
|
fn address_ptr() -> *const VMFunctionBody {
|
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Self::func_wrapper as *const () as *const VMFunctionBody
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|
}
|
|
|
|
// This function wraps our func, to make it compatible with the
|
|
// reverse trampoline signature
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unsafe fn func_wrapper(
|
|
// Note: we use the trick that the first param to this function is the `VMDynamicFunctionContext`
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|
// itself, so rather than doing `dynamic_ctx: &VMDynamicFunctionContext<T>`, we simplify it a bit
|
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&self,
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values_vec: *mut i128,
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) {
|
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use std::panic::{self, AssertUnwindSafe};
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let result = panic::catch_unwind(AssertUnwindSafe(|| {
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let func_ty = self.ctx.function_type();
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let mut args = Vec::with_capacity(func_ty.params().len());
|
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for (i, ty) in func_ty.params().iter().enumerate() {
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args.push(Val::read_value_from(values_vec.add(i), *ty));
|
|
}
|
|
let returns = self.ctx.call(&args)?;
|
|
|
|
// We need to dynamically check that the returns
|
|
// match the expected types, as well as expected length.
|
|
let return_types = returns.iter().map(|ret| ret.ty()).collect::<Vec<_>>();
|
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if return_types != func_ty.results() {
|
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return Err(RuntimeError::new(format!(
|
|
"Dynamic function returned wrong signature. Expected {:?} but got {:?}",
|
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func_ty.results(),
|
|
return_types
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|
)));
|
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}
|
|
for (i, ret) in returns.iter().enumerate() {
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ret.write_value_to(values_vec.add(i));
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}
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Ok(())
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|
}));
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|
|
match result {
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|
Ok(Ok(())) => {}
|
|
Ok(Err(trap)) => raise_user_trap(Box::new(trap)),
|
|
Err(panic) => resume_panic(panic),
|
|
}
|
|
}
|
|
}
|
|
|
|
/// This private inner module contains the low-level implementation
|
|
/// for `Function` and its siblings.
|
|
mod inner {
|
|
use std::array::TryFromSliceError;
|
|
use std::convert::{Infallible, TryInto};
|
|
use std::error::Error;
|
|
use std::marker::PhantomData;
|
|
use std::panic::{self, AssertUnwindSafe};
|
|
use wasm_common::{FunctionType, NativeWasmType, Type};
|
|
use wasmer_runtime::{raise_user_trap, resume_panic, VMFunctionBody};
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|
|
|
/// A trait to convert a Rust value to a `WasmNativeType` value,
|
|
/// or to convert `WasmNativeType` value to a Rust value.
|
|
///
|
|
/// This trait should ideally be splitted into two traits:
|
|
/// `FromNativeWasmType` and `ToNativeWasmType` but it creates a
|
|
/// non-negligeable complexity in the `WasmTypeList`
|
|
/// implementation.
|
|
pub unsafe trait FromToNativeWasmType: Copy
|
|
where
|
|
Self: Sized,
|
|
{
|
|
/// Native Wasm type.
|
|
type Native: NativeWasmType;
|
|
|
|
/// Convert a value of kind `Self::Native` to `Self`.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// This method panics if `native` cannot fit in the `Self`
|
|
/// type`.
|
|
fn from_native(native: Self::Native) -> Self;
|
|
|
|
/// Convert self to `Self::Native`.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// This method panics if `self` cannot fit in the
|
|
/// `Self::Native` type.
|
|
fn to_native(self) -> Self::Native;
|
|
}
|
|
|
|
macro_rules! from_to_native_wasm_type {
|
|
( $( $type:ty => $native_type:ty ),* ) => {
|
|
$(
|
|
#[allow(clippy::use_self)]
|
|
unsafe impl FromToNativeWasmType for $type {
|
|
type Native = $native_type;
|
|
|
|
#[inline]
|
|
fn from_native(native: Self::Native) -> Self {
|
|
native.try_into().expect(concat!(
|
|
"out of range type conversion attempt (tried to convert `",
|
|
stringify!($native_type),
|
|
"` to `",
|
|
stringify!($type),
|
|
"`)",
|
|
))
|
|
}
|
|
|
|
#[inline]
|
|
fn to_native(self) -> Self::Native {
|
|
self.try_into().expect(concat!(
|
|
"out of range type conversion attempt (tried to convert `",
|
|
stringify!($type),
|
|
"` to `",
|
|
stringify!($native_type),
|
|
"`)",
|
|
))
|
|
}
|
|
}
|
|
)*
|
|
};
|
|
}
|
|
|
|
from_to_native_wasm_type!(
|
|
i8 => i32,
|
|
u8 => i32,
|
|
i16 => i32,
|
|
u16 => i32,
|
|
i32 => i32,
|
|
u32 => i32,
|
|
i64 => i64,
|
|
u64 => i64,
|
|
f32 => f32,
|
|
f64 => f64
|
|
);
|
|
|
|
#[cfg(test)]
|
|
mod test_from_to_native_wasm_type {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn test_to_native() {
|
|
assert_eq!(7i8.to_native(), 7i32);
|
|
}
|
|
|
|
#[test]
|
|
#[should_panic(
|
|
expected = "out of range type conversion attempt (tried to convert `u32` to `i32`)"
|
|
)]
|
|
fn test_to_native_panics() {
|
|
use std::{i32, u32};
|
|
|
|
assert_eq!(u32::MAX.to_native(), i32::MAX);
|
|
}
|
|
}
|
|
|
|
/// The `WasmTypeList` trait represents a tuple (list) of Wasm
|
|
/// typed values. It is used to get low-level representation of
|
|
/// such a tuple.
|
|
pub trait WasmTypeList
|
|
where
|
|
Self: Sized,
|
|
{
|
|
/// The C type (a struct) that can hold/represent all the
|
|
/// represented values.
|
|
type CStruct;
|
|
|
|
/// The array type that can hold all the represented values.
|
|
///
|
|
/// Note that all values are stored in their binary form.
|
|
type Array: AsMut<[i128]>;
|
|
|
|
/// Constructs `Self` based on an array of values.
|
|
fn from_array(array: Self::Array) -> Self;
|
|
|
|
/// Constructs `Self` based on a slice of values.
|
|
///
|
|
/// `from_slice` returns a `Result` because it is possible
|
|
/// that the slice doesn't have the same size than
|
|
/// `Self::Array`, in which circumstance an error of kind
|
|
/// `TryFromSliceError` will be returned.
|
|
fn from_slice(slice: &[i128]) -> Result<Self, TryFromSliceError>;
|
|
|
|
/// Builds and returns an array of type `Array` from a tuple
|
|
/// (list) of values.
|
|
fn into_array(self) -> Self::Array;
|
|
|
|
/// Allocates and return an empty array of type `Array` that
|
|
/// will hold a tuple (list) of values, usually to hold the
|
|
/// returned values of a WebAssembly function call.
|
|
fn empty_array() -> Self::Array;
|
|
|
|
/// Builds a tuple (list) of values from a C struct of type
|
|
/// `CStruct`.
|
|
fn from_c_struct(c_struct: Self::CStruct) -> Self;
|
|
|
|
/// Builds and returns a C struct of type `CStruct` from a
|
|
/// tuple (list) of values.
|
|
fn into_c_struct(self) -> Self::CStruct;
|
|
|
|
/// Get the Wasm types for the tuple (list) of currently
|
|
/// represented values.
|
|
fn wasm_types() -> &'static [Type];
|
|
}
|
|
|
|
/// The `IntoResult` trait turns a `WasmTypeList` into a
|
|
/// `Result<WasmTypeList, Self::Error>`.
|
|
///
|
|
/// It is mostly used to turn result values of a Wasm function
|
|
/// call into a `Result`.
|
|
pub trait IntoResult<T>
|
|
where
|
|
T: WasmTypeList,
|
|
{
|
|
/// The error type for this trait.
|
|
type Error: Error + Sync + Send + 'static;
|
|
|
|
/// Transforms `Self` into a `Result`.
|
|
fn into_result(self) -> Result<T, Self::Error>;
|
|
}
|
|
|
|
impl<T> IntoResult<T> for T
|
|
where
|
|
T: WasmTypeList,
|
|
{
|
|
// `T` is not a `Result`, it's already a value, so no error
|
|
// can be built.
|
|
type Error = Infallible;
|
|
|
|
fn into_result(self) -> Result<Self, Infallible> {
|
|
Ok(self)
|
|
}
|
|
}
|
|
|
|
impl<T, E> IntoResult<T> for Result<T, E>
|
|
where
|
|
T: WasmTypeList,
|
|
E: Error + Sync + Send + 'static,
|
|
{
|
|
type Error = E;
|
|
|
|
fn into_result(self) -> Self {
|
|
self
|
|
}
|
|
}
|
|
|
|
/// The `HostFunction` trait represents the set of functions that
|
|
/// can be used as host function. To uphold this statement, it is
|
|
/// necessary for a function to be transformed into a pointer to
|
|
/// `VMFunctionBody`.
|
|
pub trait HostFunction<Args, Rets, Kind, T>
|
|
where
|
|
Args: WasmTypeList,
|
|
Rets: WasmTypeList,
|
|
Kind: HostFunctionKind,
|
|
T: Sized,
|
|
Self: Sized,
|
|
{
|
|
/// Get the pointer to the function body.
|
|
fn function_body_ptr(self) -> *const VMFunctionBody;
|
|
}
|
|
|
|
/// Empty trait to specify the kind of `HostFunction`: With or
|
|
/// without an environment.
|
|
///
|
|
/// This trait is never aimed to be used by a user. It is used by
|
|
/// the trait system to automatically generate the appropriate
|
|
/// host functions.
|
|
#[doc(hidden)]
|
|
pub trait HostFunctionKind {}
|
|
|
|
/// An empty struct to help Rust typing to determine
|
|
/// when a `HostFunction` does have an environment.
|
|
pub struct WithEnv;
|
|
|
|
impl HostFunctionKind for WithEnv {}
|
|
|
|
/// An empty struct to help Rust typing to determine
|
|
/// when a `HostFunction` does not have an environment.
|
|
pub struct WithoutEnv;
|
|
|
|
impl HostFunctionKind for WithoutEnv {}
|
|
|
|
/// Represents a low-level Wasm static host function. See
|
|
/// `super::Function::new` and `super::Function::new_env` to learn
|
|
/// more.
|
|
#[derive(Clone, Debug, Hash, PartialEq, Eq)]
|
|
pub struct Function<Args = (), Rets = ()> {
|
|
address: *const VMFunctionBody,
|
|
_phantom: PhantomData<(Args, Rets)>,
|
|
}
|
|
|
|
unsafe impl<Args, Rets> Send for Function<Args, Rets> {}
|
|
|
|
impl<Args, Rets> Function<Args, Rets>
|
|
where
|
|
Args: WasmTypeList,
|
|
Rets: WasmTypeList,
|
|
{
|
|
/// Creates a new `Function`.
|
|
pub fn new<F, T, E>(function: F) -> Self
|
|
where
|
|
F: HostFunction<Args, Rets, T, E>,
|
|
T: HostFunctionKind,
|
|
E: Sized,
|
|
{
|
|
Self {
|
|
address: function.function_body_ptr(),
|
|
_phantom: PhantomData,
|
|
}
|
|
}
|
|
|
|
/// Get the function type of this `Function`.
|
|
pub fn ty(&self) -> FunctionType {
|
|
FunctionType::new(Args::wasm_types(), Rets::wasm_types())
|
|
}
|
|
|
|
/// Get the address of this `Function`.
|
|
pub fn address(&self) -> *const VMFunctionBody {
|
|
self.address
|
|
}
|
|
}
|
|
|
|
macro_rules! impl_host_function {
|
|
( [$c_struct_representation:ident]
|
|
$c_struct_name:ident,
|
|
$( $x:ident ),* ) => {
|
|
|
|
/// A structure with a C-compatible representation that can hold a set of Wasm values.
|
|
/// This type is used by `WasmTypeList::CStruct`.
|
|
#[repr($c_struct_representation)]
|
|
pub struct $c_struct_name< $( $x ),* > ( $( <$x as FromToNativeWasmType>::Native ),* )
|
|
where
|
|
$( $x: FromToNativeWasmType ),*;
|
|
|
|
// Implement `WasmTypeList` for a specific tuple.
|
|
#[allow(unused_parens, dead_code)]
|
|
impl< $( $x ),* >
|
|
WasmTypeList
|
|
for
|
|
( $( $x ),* )
|
|
where
|
|
$( $x: FromToNativeWasmType ),*
|
|
{
|
|
type CStruct = $c_struct_name< $( $x ),* >;
|
|
|
|
type Array = [i128; count_idents!( $( $x ),* )];
|
|
|
|
fn from_array(array: Self::Array) -> Self {
|
|
// Unpack items of the array.
|
|
#[allow(non_snake_case)]
|
|
let [ $( $x ),* ] = array;
|
|
|
|
// Build the tuple.
|
|
(
|
|
$(
|
|
FromToNativeWasmType::from_native(NativeWasmType::from_binary($x))
|
|
),*
|
|
)
|
|
}
|
|
|
|
fn from_slice(slice: &[i128]) -> Result<Self, TryFromSliceError> {
|
|
Ok(Self::from_array(slice.try_into()?))
|
|
}
|
|
|
|
fn into_array(self) -> Self::Array {
|
|
// Unpack items of the tuple.
|
|
#[allow(non_snake_case)]
|
|
let ( $( $x ),* ) = self;
|
|
|
|
// Build the array.
|
|
[
|
|
$(
|
|
FromToNativeWasmType::to_native($x).to_binary()
|
|
),*
|
|
]
|
|
}
|
|
|
|
fn empty_array() -> Self::Array {
|
|
// Build an array initialized with `0`.
|
|
[0; count_idents!( $( $x ),* )]
|
|
}
|
|
|
|
fn from_c_struct(c_struct: Self::CStruct) -> Self {
|
|
// Unpack items of the C structure.
|
|
#[allow(non_snake_case)]
|
|
let $c_struct_name( $( $x ),* ) = c_struct;
|
|
|
|
(
|
|
$(
|
|
FromToNativeWasmType::from_native($x)
|
|
),*
|
|
)
|
|
}
|
|
|
|
#[allow(unused_parens, non_snake_case)]
|
|
fn into_c_struct(self) -> Self::CStruct {
|
|
// Unpack items of the tuple.
|
|
let ( $( $x ),* ) = self;
|
|
|
|
// Build the C structure.
|
|
$c_struct_name(
|
|
$(
|
|
FromToNativeWasmType::to_native($x)
|
|
),*
|
|
)
|
|
}
|
|
|
|
fn wasm_types() -> &'static [Type] {
|
|
&[
|
|
$(
|
|
$x::Native::WASM_TYPE
|
|
),*
|
|
]
|
|
}
|
|
}
|
|
|
|
// Implement `HostFunction` for a function that has the same arity than the tuple.
|
|
// This specific function has no environment.
|
|
#[allow(unused_parens)]
|
|
impl< $( $x, )* Rets, RetsAsResult, Func >
|
|
HostFunction<( $( $x ),* ), Rets, WithoutEnv, ()>
|
|
for
|
|
Func
|
|
where
|
|
$( $x: FromToNativeWasmType, )*
|
|
Rets: WasmTypeList,
|
|
RetsAsResult: IntoResult<Rets>,
|
|
Func: Fn($( $x , )*) -> RetsAsResult + 'static + Send,
|
|
{
|
|
#[allow(non_snake_case)]
|
|
fn function_body_ptr(self) -> *const VMFunctionBody {
|
|
/// This is a function that wraps the real host
|
|
/// function. Its address will be used inside the
|
|
/// runtime.
|
|
extern fn func_wrapper<$( $x, )* Rets, RetsAsResult, Func>( _: usize, $($x: $x::Native, )* ) -> Rets::CStruct
|
|
where
|
|
$( $x: FromToNativeWasmType, )*
|
|
Rets: WasmTypeList,
|
|
RetsAsResult: IntoResult<Rets>,
|
|
Func: Fn( $( $x ),* ) -> RetsAsResult + 'static
|
|
{
|
|
let func: &Func = unsafe { &*(&() as *const () as *const Func) };
|
|
let result = panic::catch_unwind(AssertUnwindSafe(|| {
|
|
func( $( FromToNativeWasmType::from_native($x) ),* ).into_result()
|
|
}));
|
|
|
|
match result {
|
|
Ok(Ok(result)) => return result.into_c_struct(),
|
|
Ok(Err(trap)) => unsafe { raise_user_trap(Box::new(trap)) },
|
|
Err(panic) => unsafe { resume_panic(panic) },
|
|
}
|
|
}
|
|
|
|
func_wrapper::<$( $x, )* Rets, RetsAsResult, Self> as *const VMFunctionBody
|
|
}
|
|
}
|
|
|
|
#[allow(unused_parens)]
|
|
impl< $( $x, )* Rets, RetsAsResult, Env, Func >
|
|
HostFunction<( $( $x ),* ), Rets, WithEnv, Env>
|
|
for
|
|
Func
|
|
where
|
|
$( $x: FromToNativeWasmType, )*
|
|
Rets: WasmTypeList,
|
|
RetsAsResult: IntoResult<Rets>,
|
|
Env: Sized,
|
|
Func: Fn(&mut Env, $( $x , )*) -> RetsAsResult + Send + 'static,
|
|
{
|
|
#[allow(non_snake_case)]
|
|
fn function_body_ptr(self) -> *const VMFunctionBody {
|
|
/// This is a function that wraps the real host
|
|
/// function. Its address will be used inside the
|
|
/// runtime.
|
|
extern fn func_wrapper<$( $x, )* Rets, RetsAsResult, Env, Func>( env: &mut Env, $( $x: $x::Native, )* ) -> Rets::CStruct
|
|
where
|
|
$( $x: FromToNativeWasmType, )*
|
|
Rets: WasmTypeList,
|
|
RetsAsResult: IntoResult<Rets>,
|
|
Env: Sized,
|
|
Func: Fn(&mut Env, $( $x ),* ) -> RetsAsResult + 'static
|
|
{
|
|
let func: &Func = unsafe { &*(&() as *const () as *const Func) };
|
|
|
|
let result = panic::catch_unwind(AssertUnwindSafe(|| {
|
|
func(env, $( FromToNativeWasmType::from_native($x) ),* ).into_result()
|
|
}));
|
|
|
|
match result {
|
|
Ok(Ok(result)) => return result.into_c_struct(),
|
|
Ok(Err(trap)) => unsafe { raise_user_trap(Box::new(trap)) },
|
|
Err(panic) => unsafe { resume_panic(panic) },
|
|
}
|
|
}
|
|
|
|
func_wrapper::<$( $x, )* Rets, RetsAsResult, Env, Self> as *const VMFunctionBody
|
|
}
|
|
}
|
|
|
|
};
|
|
}
|
|
|
|
// Black-magic to count the number of identifiers at compile-time.
|
|
macro_rules! count_idents {
|
|
( $($idents:ident),* ) => {
|
|
{
|
|
#[allow(dead_code, non_camel_case_types)]
|
|
enum Idents { $( $idents, )* __CountIdentsLast }
|
|
const COUNT: usize = Idents::__CountIdentsLast as usize;
|
|
COUNT
|
|
}
|
|
};
|
|
}
|
|
|
|
// Here we go! Let's generate all the C struct, `WasmTypeList`
|
|
// implementations and `HostFunction` implementations.
|
|
impl_host_function!([C] S0,);
|
|
impl_host_function!([transparent] S1, A1);
|
|
impl_host_function!([C] S2, A1, A2);
|
|
impl_host_function!([C] S3, A1, A2, A3);
|
|
impl_host_function!([C] S4, A1, A2, A3, A4);
|
|
impl_host_function!([C] S5, A1, A2, A3, A4, A5);
|
|
impl_host_function!([C] S6, A1, A2, A3, A4, A5, A6);
|
|
impl_host_function!([C] S7, A1, A2, A3, A4, A5, A6, A7);
|
|
impl_host_function!([C] S8, A1, A2, A3, A4, A5, A6, A7, A8);
|
|
impl_host_function!([C] S9, A1, A2, A3, A4, A5, A6, A7, A8, A9);
|
|
impl_host_function!([C] S10, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10);
|
|
impl_host_function!([C] S11, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11);
|
|
impl_host_function!([C] S12, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12);
|
|
impl_host_function!([C] S13, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13);
|
|
impl_host_function!([C] S14, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14);
|
|
impl_host_function!([C] S15, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15);
|
|
impl_host_function!([C] S16, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16);
|
|
impl_host_function!([C] S17, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17);
|
|
impl_host_function!([C] S18, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18);
|
|
impl_host_function!([C] S19, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19);
|
|
impl_host_function!([C] S20, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20);
|
|
impl_host_function!([C] S21, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21);
|
|
impl_host_function!([C] S22, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22);
|
|
impl_host_function!([C] S23, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23);
|
|
impl_host_function!([C] S24, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24);
|
|
impl_host_function!([C] S25, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25);
|
|
impl_host_function!([C] S26, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26);
|
|
|
|
// Implement `WasmTypeList` on `Infallible`, which means that
|
|
// `Infallible` can be used as a returned type of a host function
|
|
// to express that it doesn't return.
|
|
impl WasmTypeList for Infallible {
|
|
type CStruct = Self;
|
|
type Array = [i128; 0];
|
|
|
|
fn from_array(_: Self::Array) -> Self {
|
|
unreachable!()
|
|
}
|
|
|
|
fn from_slice(_: &[i128]) -> Result<Self, TryFromSliceError> {
|
|
unreachable!()
|
|
}
|
|
|
|
fn into_array(self) -> Self::Array {
|
|
[]
|
|
}
|
|
|
|
fn empty_array() -> Self::Array {
|
|
unreachable!()
|
|
}
|
|
|
|
fn from_c_struct(_: Self::CStruct) -> Self {
|
|
unreachable!()
|
|
}
|
|
|
|
fn into_c_struct(self) -> Self::CStruct {
|
|
unreachable!()
|
|
}
|
|
|
|
fn wasm_types() -> &'static [Type] {
|
|
&[]
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod test_wasm_type_list {
|
|
use super::*;
|
|
use wasm_common::Type;
|
|
|
|
#[test]
|
|
fn test_from_array() {
|
|
assert_eq!(<()>::from_array([]), ());
|
|
assert_eq!(<i32>::from_array([1]), (1i32));
|
|
assert_eq!(<(i32, i64)>::from_array([1, 2]), (1i32, 2i64));
|
|
assert_eq!(
|
|
<(i32, i64, f32, f64)>::from_array([
|
|
1,
|
|
2,
|
|
(3.1f32).to_bits().into(),
|
|
(4.2f64).to_bits().into()
|
|
]),
|
|
(1, 2, 3.1f32, 4.2f64)
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_into_array() {
|
|
assert_eq!(().into_array(), []);
|
|
assert_eq!((1).into_array(), [1]);
|
|
assert_eq!((1i32, 2i64).into_array(), [1, 2]);
|
|
assert_eq!(
|
|
(1i32, 2i32, 3.1f32, 4.2f64).into_array(),
|
|
[1, 2, (3.1f32).to_bits().into(), (4.2f64).to_bits().into()]
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_empty_array() {
|
|
assert_eq!(<()>::empty_array().len(), 0);
|
|
assert_eq!(<i32>::empty_array().len(), 1);
|
|
assert_eq!(<(i32, i64)>::empty_array().len(), 2);
|
|
}
|
|
|
|
#[test]
|
|
fn test_from_c_struct() {
|
|
assert_eq!(<()>::from_c_struct(S0()), ());
|
|
assert_eq!(<i32>::from_c_struct(S1(1)), (1i32));
|
|
assert_eq!(<(i32, i64)>::from_c_struct(S2(1, 2)), (1i32, 2i64));
|
|
assert_eq!(
|
|
<(i32, i64, f32, f64)>::from_c_struct(S4(1, 2, 3.1, 4.2)),
|
|
(1i32, 2i64, 3.1f32, 4.2f64)
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_wasm_types_for_uni_values() {
|
|
assert_eq!(<i32>::wasm_types(), [Type::I32]);
|
|
assert_eq!(<i64>::wasm_types(), [Type::I64]);
|
|
assert_eq!(<f32>::wasm_types(), [Type::F32]);
|
|
assert_eq!(<f64>::wasm_types(), [Type::F64]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_wasm_types_for_multi_values() {
|
|
assert_eq!(<(i32, i32)>::wasm_types(), [Type::I32, Type::I32]);
|
|
assert_eq!(<(i64, i64)>::wasm_types(), [Type::I64, Type::I64]);
|
|
assert_eq!(<(f32, f32)>::wasm_types(), [Type::F32, Type::F32]);
|
|
assert_eq!(<(f64, f64)>::wasm_types(), [Type::F64, Type::F64]);
|
|
|
|
assert_eq!(
|
|
<(i32, i64, f32, f64)>::wasm_types(),
|
|
[Type::I32, Type::I64, Type::F32, Type::F64]
|
|
);
|
|
}
|
|
}
|
|
|
|
#[allow(non_snake_case)]
|
|
#[cfg(test)]
|
|
mod test_function {
|
|
use super::*;
|
|
use wasm_common::Type;
|
|
|
|
fn func() {}
|
|
fn func__i32() -> i32 {
|
|
0
|
|
}
|
|
fn func_i32(_a: i32) {}
|
|
fn func_i32__i32(a: i32) -> i32 {
|
|
a * 2
|
|
}
|
|
fn func_i32_i32__i32(a: i32, b: i32) -> i32 {
|
|
a + b
|
|
}
|
|
fn func_i32_i32__i32_i32(a: i32, b: i32) -> (i32, i32) {
|
|
(a, b)
|
|
}
|
|
fn func_f32_i32__i32_f32(a: f32, b: i32) -> (i32, f32) {
|
|
(b, a)
|
|
}
|
|
|
|
#[test]
|
|
fn test_function_types() {
|
|
assert_eq!(Function::new(func).ty(), FunctionType::new(vec![], vec![]));
|
|
assert_eq!(
|
|
Function::new(func__i32).ty(),
|
|
FunctionType::new(vec![], vec![Type::I32])
|
|
);
|
|
assert_eq!(
|
|
Function::new(func_i32).ty(),
|
|
FunctionType::new(vec![Type::I32], vec![])
|
|
);
|
|
assert_eq!(
|
|
Function::new(func_i32__i32).ty(),
|
|
FunctionType::new(vec![Type::I32], vec![Type::I32])
|
|
);
|
|
assert_eq!(
|
|
Function::new(func_i32_i32__i32).ty(),
|
|
FunctionType::new(vec![Type::I32, Type::I32], vec![Type::I32])
|
|
);
|
|
assert_eq!(
|
|
Function::new(func_i32_i32__i32_i32).ty(),
|
|
FunctionType::new(vec![Type::I32, Type::I32], vec![Type::I32, Type::I32])
|
|
);
|
|
assert_eq!(
|
|
Function::new(func_f32_i32__i32_f32).ty(),
|
|
FunctionType::new(vec![Type::F32, Type::I32], vec![Type::I32, Type::F32])
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_function_pointer() {
|
|
let f = Function::new(func_i32__i32);
|
|
let function = unsafe { std::mem::transmute::<_, fn(usize, i32) -> i32>(f.address) };
|
|
assert_eq!(function(0, 3), 6);
|
|
}
|
|
}
|
|
}
|