The previous few commits have made this more obvious, and removed the
one exception. Time to clarify the documentation, and drop dead error
checking.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200424084338.26803-13-armbru@redhat.com>
The contract demands v->start_alternate() for input and dealloc
visitors, but visit_start_alternate() actually requires it for input
and clone visitors. Fix the contract, and delete superfluous
qapi_dealloc_start_alternate().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200424084338.26803-8-armbru@redhat.com>
Mostly, Error ** is for returning error from the function, so the
callee sets it. However these three functions get already filled errp
parameter. They don't change the pointer itself, only change the
internal state of referenced Error object. So we can make it
Error *const * errp, to stress the behavior. It will also help
coccinelle script (in future) to distinguish such cases from common
errp usage.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20191205174635.18758-4-vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message typo fixed]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
visit_next_list() returns non-null on success, null on failure. The
comment's phrasing "until NULL return or error occurs" is needlessly
confusing. Scratch the "or error occurs" part.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190802122325.16520-1-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
In my "build everything" tree, changing a type in qapi/common.json
triggers a recompile of some 3600 out of 6600 objects (not counting
tests and objects that don't depend on qemu/osdep.h).
One common dependency is QapiErrorClass: it's used only in in
qapi/error.h, which uses nothing else, and is widely included.
Move QapiErrorClass from common.json to new error.json. Touching
common.json now recompiles only some 2900 objects.
Cc: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-4-armbru@redhat.com>
The qapi_event_send_FOO() functions emit events like this:
QMPEventFuncEmit emit;
emit = qmp_event_get_func_emit();
if (!emit) {
return;
}
qmp = qmp_event_build_dict("FOO");
[put event arguments into @qmp...]
emit(QAPI_EVENT_FOO, qmp);
The value of qmp_event_get_func_emit() depends only on the program:
* In qemu-system-FOO, it's always monitor_qapi_event_queue.
* In tests/test-qmp-event, it's always event_test_emit.
* In all other programs, it's always null.
This is exactly the kind of dependence the linker is supposed to
resolve; we don't actually need an indirection.
Note that things would fall apart if we linked more than one QAPI
schema into a single program: each set of qapi_event_send_FOO() uses
its own event enumeration, yet they share a single emit function.
Which takes the event enumeration as an argument. Which one if
there's more than one?
More seriously: how does this work even now? qemu-system-FOO wants
QAPIEvent, and passes a function taking that to
qmp_event_set_func_emit(). test-qmp-event wants test_QAPIEvent, and
passes a function taking that to qmp_event_set_func_emit().
It works by type trickery, of course:
typedef void (*QMPEventFuncEmit)(unsigned event, QDict *dict);
void qmp_event_set_func_emit(QMPEventFuncEmit emit);
QMPEventFuncEmit qmp_event_get_func_emit(void);
We use unsigned instead of the enumeration type. Relies on both
enumerations boiling down to unsigned, which happens to be true for
the compilers we use.
Clean this up as follows:
* Generate qapi_event_send_FOO() that call PREFIX_qapi_event_emit()
instead of the value of qmp_event_set_func_emit().
* Generate a prototype for PREFIX_qapi_event_emit() into
qapi-events.h.
* PREFIX_ is empty for qapi/qapi-schema.json, and test_ for
tests/qapi-schema/qapi-schema-test.json. It's qga_ for
qga/qapi-schema.json, and doc-good- for
tests/qapi-schema/doc-good.json, but those don't define any events.
* Rename monitor_qapi_event_queue() to qapi_event_emit() instead of
passing it to qmp_event_set_func_emit(). This takes care of
qemu-system-FOO.
* Rename event_test_emit() to test_qapi_event_emit() instead of
passing it to qmp_event_set_func_emit(). This takes care of
tests/test-qmp-event.
* Add a qapi_event_emit() that does nothing to stubs/monitor.c. This
takes care of all other programs that link code emitting QMP events.
* Drop qmp_event_set_func_emit(), qmp_event_get_func_emit().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181218182234.28876-3-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[Commit message typos fixed]
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>
From include/qapi/error.h:
* Pass an existing error to the caller with the message modified:
* error_propagate(errp, err);
* error_prepend(errp, "Could not frobnicate '%s': ", name);
Fei Li pointed out that doing error_propagate() first doesn't work
well when @errp is &error_fatal or &error_abort: the error_prepend()
is never reached.
Since I doubt fixing the documentation will stop people from getting
it wrong, introduce error_propagate_prepend(), in the hope that it
lures people away from using its constituents in the wrong order.
Update the instructions in error.h accordingly.
Convert existing error_prepend() next to error_propagate to
error_propagate_prepend(). If any of these get reached with
&error_fatal or &error_abort, the error messages improve. I didn't
check whether that's the case anywhere.
Cc: Fei Li <fli@suse.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20181017082702.5581-2-armbru@redhat.com>
qerror.h contains leftovers from the now-defunct QError API.
There's only a handful of string macros left, and no one is supposed
to add anything else. The check-qerror.sh script was used to make sure
that all definitions on the qerror.c and qerror.h files were sorted
alphabetically. The former was removed three years ago, and the latter
is now in a different location, so the script doesn't even work (as
a matter of fact the alphabetical order was broken last time someone
added a macro -also in 2015- and no one seemed to notice).
There's no point in fixing this script so let's just remove it.
The rogue macro is also moved to its correct location.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20181017151738.20299-1-berto@igalia.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The generated qapi_event_send_FOO() take an Error ** argument. They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().
Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.
Suggested-by: Eric Blake <eblake@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
