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 <arm...@redhat.com>
Message-Id: <20181218182234.28876-3-arm...@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lur...@redhat.com>
[Commit message typos fixed]
---
docs/devel/qapi-code-gen.txt | 8 +-------
include/qapi/qmp-event.h | 6 ------
monitor.c | 4 +---
qapi/qmp-event.c | 12 ------------
scripts/qapi/events.py | 24 ++++++++++++++----------
stubs/monitor.c | 5 +++++
tests/Makefile.include | 4 ++--
tests/test-qmp-event.c | 6 +-----
8 files changed, 24 insertions(+), 45 deletions(-)
diff --git a/docs/devel/qapi-code-gen.txt b/docs/devel/qapi-code-gen.txt
index 418a607842..87183d3a09 100644
--- a/docs/devel/qapi-code-gen.txt
+++ b/docs/devel/qapi-code-gen.txt
@@ -1385,16 +1385,10 @@ Example:
void qapi_event_send_my_event(void)
{
QDict *qmp;
- QMPEventFuncEmit emit;
-
- emit = qmp_event_get_func_emit();
- if (!emit) {
- return;
- }
qmp = qmp_event_build_dict("MY_EVENT");
- emit(EXAMPLE_QAPI_EVENT_MY_EVENT, qmp);
+ example_qapi_event_emit(EXAMPLE_QAPI_EVENT_MY_EVENT, qmp);
qobject_unref(qmp);
}
diff --git a/include/qapi/qmp-event.h b/include/qapi/qmp-event.h
index 23e588ccf8..b60f1d3a89 100644
--- a/include/qapi/qmp-event.h
+++ b/include/qapi/qmp-event.h
@@ -14,11 +14,5 @@
#ifndef QMP_EVENT_H
#define QMP_EVENT_H
-typedef void (*QMPEventFuncEmit)(unsigned event, QDict *dict);
-
-void qmp_event_set_func_emit(QMPEventFuncEmit emit);
-
-QMPEventFuncEmit qmp_event_get_func_emit(void);
-
QDict *qmp_event_build_dict(const char *event_name);
#endif
diff --git a/monitor.c b/monitor.c
index eb39fb015b..c09fa63940 100644
--- a/monitor.c
+++ b/monitor.c
@@ -590,8 +590,7 @@ monitor_qapi_event_queue_no_reenter(QAPIEvent event, QDict
*qdict)
qemu_mutex_unlock(&monitor_lock);
}
-static void
-monitor_qapi_event_queue(QAPIEvent event, QDict *qdict)
+void qapi_event_emit(QAPIEvent event, QDict *qdict)
{
/*
* monitor_qapi_event_queue_no_reenter() is not reentrant: it
@@ -704,7 +703,6 @@ static void monitor_qapi_event_init(void)
{
monitor_qapi_event_state = g_hash_table_new(qapi_event_throttle_hash,
qapi_event_throttle_equal);
- qmp_event_set_func_emit(monitor_qapi_event_queue);
}
static void handle_hmp_command(Monitor *mon, const char *cmdline);
diff --git a/qapi/qmp-event.c b/qapi/qmp-event.c
index 5b8854043e..81ddd5331f 100644
--- a/qapi/qmp-event.c
+++ b/qapi/qmp-event.c
@@ -19,18 +19,6 @@
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qjson.h"
-static QMPEventFuncEmit qmp_emit;
-
-void qmp_event_set_func_emit(QMPEventFuncEmit emit)
-{
- qmp_emit = emit;
-}
-
-QMPEventFuncEmit qmp_event_get_func_emit(void)
-{
- return qmp_emit;
-}
-
static void timestamp_put(QDict *qdict)
{
int err;
diff --git a/scripts/qapi/events.py b/scripts/qapi/events.py
index 37ee5de682..d86a2d2b3e 100644
--- a/scripts/qapi/events.py
+++ b/scripts/qapi/events.py
@@ -58,7 +58,7 @@ def gen_param_var(typ):
return ret
-def gen_event_send(name, arg_type, boxed, event_enum_name):
+def gen_event_send(name, arg_type, boxed, event_enum_name, event_emit):
# FIXME: Our declaration of local variables (and of 'errp' in the
# parameter list) can collide with exploded members of the event's
# data type passed in as parameters. If this collision ever hits in
@@ -70,7 +70,6 @@ def gen_event_send(name, arg_type, boxed, event_enum_name):
%(proto)s
{
QDict *qmp;
- QMPEventFuncEmit emit;
''',
proto=build_event_send_proto(name, arg_type, boxed))
@@ -86,11 +85,6 @@ def gen_event_send(name, arg_type, boxed, event_enum_name):
ret += mcgen('''
- emit = qmp_event_get_func_emit();
- if (!emit) {
- return;
- }
-
qmp = qmp_event_build_dict("%(name)s");
''',
@@ -121,9 +115,10 @@ def gen_event_send(name, arg_type, boxed, event_enum_name):
''')
ret += mcgen('''
- emit(%(c_enum)s, qmp);
+ %(event_emit)s(%(c_enum)s, qmp);
''',
+ event_emit=event_emit,
c_enum=c_enum_const(event_enum_name, name))
if arg_type and not arg_type.is_empty():
@@ -145,6 +140,7 @@ class QAPISchemaGenEventVisitor(QAPISchemaModularCVisitor):
' * Schema-defined QAPI/QMP events', __doc__)
self._event_enum_name = c_name(prefix + 'QAPIEvent', protect=False)
self._event_enum_members = []
+ self._event_emit_name = c_name(prefix + 'qapi_event_emit')
def _begin_module(self, name):
types = self._module_basename('qapi-types', name)
@@ -170,15 +166,23 @@ class
QAPISchemaGenEventVisitor(QAPISchemaModularCVisitor):
def visit_end(self):
(genc, genh) = self._module[self._main_module]
- genh.add(gen_enum(self._event_enum_name, self._event_enum_members))
+ genh.add(gen_enum(self._event_enum_name,
+ self._event_enum_members))
genc.add(gen_enum_lookup(self._event_enum_name,
self._event_enum_members))
+ genh.add(mcgen('''
+
+void %(event_emit)s(%(event_enum)s event, QDict *qdict);
+''',
+ event_emit=self._event_emit_name,
+ event_enum=self._event_enum_name))
def visit_event(self, name, info, ifcond, arg_type, boxed):
with ifcontext(ifcond, self._genh, self._genc):
self._genh.add(gen_event_send_decl(name, arg_type, boxed))
self._genc.add(gen_event_send(name, arg_type, boxed,
- self._event_enum_name))
+ self._event_enum_name,
+ self._event_emit_name))
self._event_enum_members.append(QAPISchemaMember(name, ifcond))
diff --git a/stubs/monitor.c b/stubs/monitor.c
index 3890771bb5..32bd7012c3 100644
--- a/stubs/monitor.c
+++ b/stubs/monitor.c
@@ -1,5 +1,6 @@
#include "qemu/osdep.h"
#include "qapi/error.h"
+#include "qapi/qapi-events.h"
#include "qemu-common.h"
#include "monitor/monitor.h"
@@ -14,3 +15,7 @@ int monitor_get_fd(Monitor *mon, const char *name, Error
**errp)
void monitor_init(Chardev *chr, int flags)
{
}
+
+void qapi_event_emit(QAPIEvent event, QDict *qdict)
+{
+}
diff --git a/tests/Makefile.include b/tests/Makefile.include
index 4eea38ae99..3453579af3 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -528,7 +528,7 @@ QEMU_CFLAGS += -I$(SRC_PATH)/tests
test-util-obj-y = libqemuutil.a
test-qom-obj-y = $(qom-obj-y) $(test-util-obj-y)
test-qapi-obj-y = tests/test-qapi-visit.o tests/test-qapi-types.o \
- tests/test-qapi-events.o tests/test-qapi-introspect.o \
+ tests/test-qapi-introspect.o \
$(test-qom-obj-y)
benchmark-crypto-obj-y = $(crypto-obj-y) $(test-qom-obj-y)
test-crypto-obj-y = $(crypto-obj-y) $(test-qom-obj-y)
@@ -620,7 +620,7 @@ tests/qapi-schema/doc-good.test.texi:
$(SRC_PATH)/tests/qapi-schema/doc-good.jso
tests/test-string-output-visitor$(EXESUF): tests/test-string-output-visitor.o
$(test-qapi-obj-y)
tests/test-string-input-visitor$(EXESUF): tests/test-string-input-visitor.o
$(test-qapi-obj-y)
-tests/test-qmp-event$(EXESUF): tests/test-qmp-event.o $(test-qapi-obj-y)
+tests/test-qmp-event$(EXESUF): tests/test-qmp-event.o $(test-qapi-obj-y)
tests/test-qapi-events.o
tests/test-qobject-output-visitor$(EXESUF):
tests/test-qobject-output-visitor.o $(test-qapi-obj-y)
tests/test-clone-visitor$(EXESUF): tests/test-clone-visitor.o
$(test-qapi-obj-y)
tests/test-qobject-input-visitor$(EXESUF): tests/test-qobject-input-visitor.o
$(test-qapi-obj-y)
diff --git a/tests/test-qmp-event.c b/tests/test-qmp-event.c
index 9cddd72adb..bf900f14f4 100644
--- a/tests/test-qmp-event.c
+++ b/tests/test-qmp-event.c
@@ -93,9 +93,7 @@ static bool qdict_cmp_simple(QDict *a, QDict *b)
return d.result;
}
-/* This function is hooked as final emit function, which can verify the
- correctness. */
-static void event_test_emit(test_QAPIEvent event, QDict *d)
+void test_qapi_event_emit(test_QAPIEvent event, QDict *d)
{
QDict *t;
int64_t s, ms;
@@ -241,8 +239,6 @@ static void test_event_d(TestEventData *data,
int main(int argc, char **argv)
{
- qmp_event_set_func_emit(event_test_emit);
-
g_test_init(&argc, &argv, NULL);
event_test_add("/event/event_a", test_event_a);
--
2.17.2
