QAPI patches for 2018-12-13
# gpg: Signature made Fri 14 Dec 2018 05:53:51 GMT
# gpg: using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653
* remotes/armbru/tags/pull-qapi-2018-12-13-v2: (32 commits)
qapi: add conditions to REPLICATION type/commands on the schema
qapi: add more conditions to SPICE
qapi: add condition to variants documentation
qapi: add 'If:' condition to struct members documentation
qapi: add 'If:' condition to enum values documentation
qapi: Add #if conditions to generated code members
qapi: add 'if' to alternate members
qapi: add 'if' to union members
qapi: Add 'if' to implicit struct members
qapi: add a dictionary form for TYPE
qapi-events: add 'if' condition to implicit event enum
qapi: add 'if' to enum members
qapi: add a dictionary form with 'name' key for enum members
qapi: improve reporting of unknown or missing keys
qapi: factor out checking for keys
tests: print enum type members more like object type members
qapi: change enum visitor and gen_enum* to take QAPISchemaMember
qapi: Do not define enumeration value explicitly
qapi: break long lines at 'data' member
qapi: rename QAPISchemaEnumType.values to .members
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add #if defined(CONFIG_REPLICATION) in generated code, and adjust the
code accordingly.
Made conditional:
* xen-set-replication, query-xen-replication-status,
xen-colo-do-checkpoint
Before the patch, we first register the commands unconditionally in
generated code (requires a stub), then conditionally unregister in
qmp_unregister_commands_hack().
Afterwards, we register only when CONFIG_REPLICATION. The command
fails exactly the same, with CommandNotFound.
Improvement, because now query-qmp-schema is accurate, and we're one
step closer to killing qmp_unregister_commands_hack().
* enum BlockdevDriver value "replication" in command blockdev-add
* BlockdevOptions variant @replication
and related structures.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181213123724.4866-23-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that member can be made conditional, let's make SPICE chardev
conditional:
* spiceport, spicevmc
Before and after the patch for !CONFIG_SPICE, the error is the
same ('spiceport' is not a valid char driver name).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181213123724.4866-22-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The input visitor has some problems right now, especially
- unsigned type "Range" is used to process signed ranges, resulting in
inconsistent behavior and ugly/magical code
- uint64_t are parsed like int64_t, so big uint64_t values are not
supported and error messages are misleading
- lists/ranges of int64_t are accepted although no list is parsed and
we should rather report an error
- lists/ranges are preparsed using int64_t, making it hard to
implement uint64_t values or uint64_t lists
- types that don't support lists don't bail out
- visiting beyond the end of a list is not handled properly
- we don't actually parse lists, we parse *sets*: members are sorted,
and duplicates eliminated
So let's rewrite it by getting rid of usage of the type "Range" and
properly supporting lists of int64_t and uint64_t (including ranges of
both types), fixing the above mentioned issues.
Lists of other types are not supported and will properly report an
error. Virtual walks are now supported.
Tests have to be fixed up:
- Two BUGs were hardcoded that are fixed now
- The string-input-visitor now actually returns a parsed list and not
an ordered set.
Please note that no users/callers have to be fixed up. Candidates using
visit_type_uint16List() and friends are:
- backends/hostmem.c:host_memory_backend_set_host_nodes()
-- Code can deal with duplicates/unsorted lists
- numa.c::query_memdev()
-- via object_property_get_uint16List(), the list will still be sorted
and without duplicates (via host_memory_backend_get_host_nodes())
- qapi-visit.c::visit_type_Memdev_members()
- qapi-visit.c::visit_type_NumaNodeOptions_members()
- qapi-visit.c::visit_type_RockerOfDpaGroup_members
- qapi-visit.c::visit_type_RxFilterInfo_members()
-- Not used with string-input-visitor.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181121164421.20780-7-david@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The string-input-visitor happily accepts NaN and infinities when parsing
numbers (doubles). They shouldn't. Fix that.
Also, add two test cases, testing if "NaN" and "inf" is properly
rejected.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181121164421.20780-4-david@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The values specified in the documentation don't match the actual
defaults set in qcrypto_block_luks_create().
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When a QMP client sends in-band commands more quickly that we can
process them, we can either queue them without limit (QUEUE), drop
commands when the queue is full (DROP), or suspend receiving commands
when the queue is full (SUSPEND). None of them is ideal:
* QUEUE lets a misbehaving client make QEMU eat memory without bounds.
Not such a hot idea.
* With DROP, the client has to cope with dropped in-band commands. To
inform the client, we send a COMMAND_DROPPED event then. The event is
flawed by design in two ways: it's ambiguous (see commit d621cfe0a1),
and it brings back the "eat memory without bounds" problem.
* With SUSPEND, the client has to manage the flow of in-band commands to
keep the monitor available for out-of-band commands.
We currently DROP. Switch to SUSPEND.
Managing the flow of in-band commands to keep the monitor available for
out-of-band commands isn't really hard: just count the number of
"outstanding" in-band commands (commands sent minus replies received),
and if it exceeds the limit, hold back additional ones until it drops
below the limit again.
Note that we need to be careful pairing the suspend with a resume, or
else the monitor will hang, possibly forever. And here since we need to
make sure both:
(1) popping request from the req queue, and
(2) reading length of the req queue
will be in the same critical section, we let the pop function take the
corresponding queue lock when there is a request, then we release the
lock from the caller.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-2-peterx@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The intended functionality of QMP `cpu-add` is replaced with
`device_add` (and `query-hotpluggable-cpus`). So let's deprecate
`cpu-add`.
A complete example of vCPU hotplug with the recommended way (using
`device_add`) is provided as part of a seperate docs patch.
Suggested-by: Eduardo Habkost <ehabkost@redhat.com
Signed-off-by: Kashyap Chamarthy <kchamart@redhat.com>
Message-Id: <20181030123526.26415-2-kchamart@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Add query-display-options command, which allows querying the qemu
display configuration. This isn't particularly useful, except it
exposes QAPI type DisplayOptions in query-qmp-schema, so that libvirt
can discover recently added -display parameter rendernode (commit
d4dc4ab133). Works around lack of sufficiently powerful command line
introspection.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Tested-by: Erik Skultety <eskultet@redhat.com>
Message-id: 20181122071613.2889-1-kraxel@redhat.com
[ kraxel: reworded commit message as suggested by armbru ]
If a management application builds the block graph node by node, the
protocol layer doesn't inherit its read-only option from the format
layer any more, so it must be set explicitly.
Backing files should work on read-only storage, but at the same time, a
block job like commit should be able to reopen them read-write if they
are on read-write storage. However, without option inheritance, reopen
only changes the read-only option for the root node (typically the
format layer), but not the protocol layer, so reopening fails (the
format layer wants to get write permissions, but the protocol layer is
still read-only).
A simple workaround for the problem in the management tool would be to
open the protocol layer always read-write and to make only the format
layer read-only for backing files. However, sometimes the file is
actually stored on read-only storage and we don't know whether the image
can be opened read-write (for example, for NBD it depends on the server
we're trying to connect to). This adds an option that makes QEMU try to
open the image read-write, but allows it to degrade to a read-only mode
without returning an error.
The documentation for this option is consciously phrased in a way that
allows QEMU to switch to a better model eventually: Instead of trying
when the image is first opened, making the read-only flag dynamic and
changing it automatically whenever the first BLK_PERM_WRITE user is
attached or the last one is detached would be much more useful
behaviour.
Unfortunately, this more useful behaviour is also a lot harder to
implement, and libvirt needs a solution now before it can switch to
-blockdev, so let's start with this easier approach for now.
Instead of adding a new auto-read-only option, turning the existing
read-only into an enum (with a bool alternate for compatibility) was
considered, but it complicated the implementation to the point that it
didn't seem to be worth it.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
New action is like clean action: do the whole thing in .prepare and
undo in .abort. This behavior for bitmap-changing actions is needed
because backup job actions use bitmap in .prepare.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
This new usernet option can be used to add data for option 66 (tftp
server name) in the BOOTP reply, which is useful in PXE based automatic
OS install such as OpenBSD.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Return value of qemu_timedate_diff(), used for calculation offset in
QAPI 'RTC_CHANGE' event, restored to keep compatibility. Since it
wasn't documented that difference is relative to host clock
advancement, this change also adds important note to 'RTC_CHANGE'
event description to highlight established implementation specifics.
Signed-off-by: Artem Pisarenko <artem.k.pisarenko@gmail.com>
Message-Id: <1fc12c77e8b7115d3842919a8b586d9cbe4efca6.1539846575.git.artem.k.pisarenko@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Libvirt or other high level software can use this command query colo status.
You can test this command like that:
{'execute':'query-colo-status'}
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
If some errors happen during VM's COLO FT stage, it's important to
notify the users of this event. Together with 'x-colo-lost-heartbeat',
Users can intervene in COLO's failover work immediately.
If users don't want to get involved in COLO's failover verdict,
it is still necessary to notify users that we exited COLO mode.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
According to PCI specification, subsystem id and subsystem vendor id
are present only in type 0 and type 2 headers (at different offsets),
but not in type 1 headers.
Thus we should make this data optional in struct PciDeviceId and skip
reporting them via HMP if the information is not available.
Additional (wrong information) about PCI bridges (Type1 devices) has been
added in 5383a705 and fortunately not released. This patch fixes that
problem. The problem was spotted by Markus.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181002135538.12113-1-den@openvz.org>
Reported-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Block layer patches:
- qcow2 cache option default changes (Linux: 32 MB maximum, limited by
whatever cache size can be made use of with the specific image;
default cache-clean-interval of 10 minutes)
- reopen: Allow specifying unchanged child node references, and changing
a few generic options (discard, detect-zeroes)
- Fix werror/rerror defaults for -device drive=<node-name>
- Test case fixes
# gpg: Signature made Mon 01 Oct 2018 18:17:35 BST
# gpg: using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (23 commits)
tests/test-bdrv-drain: Fix too late qemu_event_reset()
test-replication: Lock AioContext around blk_unref()
qcow2: Fix cache-clean-interval documentation
block-backend: Set werror/rerror defaults in blk_new()
qcow2: Explicit number replaced by a constant
qcow2: Set the default cache-clean-interval to 10 minutes
qcow2: Resize the cache upon image resizing
qcow2: Increase the default upper limit on the L2 cache size
qcow2: Assign the L2 cache relatively to the image size
qcow2: Avoid duplication in setting the refcount cache size
qcow2: Make sizes more humanly readable
include: Add a lookup table of sizes
qcow2: Options' documentation fixes
block: Allow changing 'detect-zeroes' on reopen
block: Allow changing 'discard' on reopen
file-posix: Forbid trying to change unsupported options during reopen
block: Forbid trying to change unsupported options during reopen
block: Allow child references on reopen
block: Don't look for child references in append_open_options()
block: Remove child references from bs->{options,explicit_options}
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fixing cache-clean-interval documentation following the recent change to
a default of 600 seconds on supported plarforms (only Linux currently).
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The default cache-clean-interval is set to 10 minutes, in order to lower
the overhead of the qcow2 caches (before the default was 0, i.e.
disabled).
* For non-Linux platforms the default is kept at 0, because
cache-clean-interval is not supported there yet.
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We named these using underscores instead of the preferred dash,
document this nearby so we cannot possibly forget to rectify this
when we remove the 'x-' prefixes when the feature becomes stable.
We do not implement the change ahead of time to avoid more work
for libvirt to do in order to figure out how to use the beta version
of the API needlessly.
Reported-by: Eric Blake <eblake@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20180919190934.16284-1-jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: typo fix]
Signed-off-by: Eric Blake <eblake@redhat.com>
Currently, it includes:
pages: amount of pages compressed and transferred to the target VM
busy: amount of count that no free thread to compress data
busy-rate: rate of thread busy
compressed-size: amount of bytes after compression
compression-rate: rate of compressed size
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180906070101.27280-3-xiaoguangrong@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Block layer patches:
- Drain fixes
- node-name parameters for block-commit
- Refactor block jobs to use transactional callbacks for exiting
# gpg: Signature made Tue 25 Sep 2018 16:12:44 BST
# gpg: using RSA key F407DB0061D5CF40
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# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1 1829 F407 DB00 61D5 CF40
* remotes/xanclic/tags/pull-block-2018-09-25: (42 commits)
test-bdrv-drain: Test draining job source child and parent
block: Use a single global AioWait
test-bdrv-drain: Fix outdated comments
test-bdrv-drain: AIO_WAIT_WHILE() in job .commit/.abort
job: Avoid deadlocks in job_completed_txn_abort()
test-bdrv-drain: Test nested poll in bdrv_drain_poll_top_level()
block: Remove aio_poll() in bdrv_drain_poll variants
blockjob: Lie better in child_job_drained_poll()
block-backend: Decrease in_flight only after callback
block-backend: Fix potential double blk_delete()
block-backend: Add .drained_poll callback
block: Add missing locking in bdrv_co_drain_bh_cb()
test-bdrv-drain: Test AIO_WAIT_WHILE() in completion callback
job: Use AIO_WAIT_WHILE() in job_finish_sync()
test-blockjob: Acquire AioContext around job_cancel_sync()
test-bdrv-drain: Drain with block jobs in an I/O thread
aio-wait: Increase num_waiters even in home thread
blockjob: Wake up BDS when job becomes idle
job: Fix missing locking due to mismerge
job: Fix nested aio_poll() hanging in job_txn_apply
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The block-commit QMP command required specifying the top and base nodes
of the commit jobs using the file name of that node. While this works
in simple cases (local files with absolute paths), the file names
generated for more complicated setups can be hard to predict.
The block-commit command has more problems than just this, so we want to
replace it altogether in the long run, but libvirt needs a reliable way
to address nodes now. So we don't want to wait for a new, cleaner
command, but just add the minimal thing needed right now.
This adds two new options top-node and base-node to the command, which
allow specifying node names instead. They are mutually exclusive with
the old options.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This is a long story. Red Hat has relicensed Windows KVM device drivers
in 2018 and there was an agreement that to avoid WHQL driver conflict
software manufacturers should set proper PCI subsystem vendor ID in
their distributions. Thus PCI subsystem vendor id becomes actively used.
The problem is that this field is applied by us via hardware compats.
Thus technically it could be lost.
This patch adds PCI susbsystem id and vendor id to exportable parameters
for validation.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180918095852.28422-1-den@openvz.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We recently removed the long deprecated "ppcemb" target. This adds a
comment in common.json about the SysEmuTarget type, recording when it was
removed.
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
ppc patch queue 2018-09-07
Here's another pull request for qemu-3.1. No real theme here, just an
assortment of various fixes. Probably the most notable thing is the
removal of the ppcemb target which has been deprecated for some time
now.
# gpg: Signature made Fri 07 Sep 2018 08:30:02 BST
# gpg: using RSA key 6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>"
# gpg: aka "David Gibson (Red Hat) <dgibson@redhat.com>"
# gpg: aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>"
# gpg: aka "David Gibson (kernel.org) <dwg@kernel.org>"
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E 87DC 6C38 CACA 20D9 B392
* remotes/dgibson/tags/ppc-for-3.1-20180907:
target-ppc: Extend HWCAP2 bits for ISA 3.0
target/ppc/kvm: set vcpu as online/offline
Fix a deadlock case in the CPU hotplug flow
spapr: Correct reference count on spapr-cpu-core
mac_newworld: implement custom FWPathProvider
uninorth: add ofw-addr property to allow correct fw path generation
mac_oldworld: implement custom FWPathProvider
grackle: set device fw_name and address for correct fw path generation
macio: add addr property to macio IDE object
macio: add macio bus to help with fw path generation
macio: move MACIOIDEState type declarations to macio.h
spapr_pci: fix potential NULL pointer dereference
spapr: fix leak of rev array
ppc: Remove deprecated ppcemb target
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
There is no known available OS for ppc around anymore that uses page
sizes below 4k, so it does not make much sense that we keep wasting
our time on building and testing the ppcemb-softmmu target. It has
been deprecated since two releases, and nobody complained, so let's
remove this now.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
QObject patches for 2018-08-24
# gpg: Signature made Fri 24 Aug 2018 20:28:53 BST
# gpg: using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653
* remotes/armbru/tags/pull-qobject-2018-08-24: (58 commits)
json: Update references to RFC 7159 to RFC 8259
json: Support %% in JSON strings when interpolating
json: Improve safety of qobject_from_jsonf_nofail() & friends
json: Keep interpolation state in JSONParserContext
tests/drive_del-test: Fix harmless JSON interpolation bug
json: Clean up headers
qobject: Drop superfluous includes of qemu-common.h
json: Make JSONToken opaque outside json-parser.c
json: Unbox tokens queue in JSONMessageParser
json: Streamline json_message_process_token()
json: Enforce token count and size limits more tightly
qjson: Have qobject_from_json() & friends reject empty and blank
json: Assert json_parser_parse() consumes all tokens on success
json: Fix streamer not to ignore trailing unterminated structures
json: Fix latent parser aborts at end of input
qjson: Fix qobject_from_json() & friends for multiple values
json: Improve names of lexer states related to numbers
json: Replace %I64d, %I64u by %PRId64, %PRIu64
json: Leave rejecting invalid interpolation to parser
json: Pass lexical errors and limit violations to callback
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The last case where qobject_from_json() & friends return null without
setting an error is empty or blank input. Callers:
* block.c's parse_json_protocol() reports "Could not parse the JSON
options". It's marked as a work-around, because it also covered
actual bugs, but they got fixed in the previous few commits.
* qobject_input_visitor_new_str() reports "JSON parse error". Also
marked as work-around. The recent fixes have made this unreachable,
because it currently gets called only for input starting with '{'.
* check-qjson.c's empty_input() and blank_input() demonstrate the
behavior.
* The other callers are not affected since they only pass input with
exactly one JSON value or, in the case of negative tests, one error.
Fail with "Expecting a JSON value" instead of returning null, and
simplify callers.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-48-armbru@redhat.com>
