qapi script: add event support

qapi-event.py will parse the schema and generate qapi-event.c, then
the API in qapi-event.c can be used to handle events in qemu code.
All API have prefix "qapi_event".

The script mainly includes two parts: generate API for each event
define, generate an enum type for all defined events.

Since in some cases the real emit behavior may change, for example,
qemu-img would not send a event, a callback layer is used to
control the behavior. As a result, the stubs at compile time
can be saved, the binding of block layer code and monitor code
will become looser.

Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/scripts/qapi.py b/scripts/qapi.py
index 0079194169..54b97cb48e 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -248,6 +248,16 @@ def discriminator_find_enum_define(expr):
 
     return find_enum(discriminator_type)
 
+def check_event(expr, expr_info):
+    params = expr.get('data')
+    if params:
+        for argname, argentry, optional, structured in parse_args(params):
+            if structured:
+                raise QAPIExprError(expr_info,
+                                    "Nested structure define in event is not "
+                                    "supported now, event '%s', argname '%s'"
+                                    % (expr['event'], argname))
+
 def check_union(expr, expr_info):
     name = expr['union']
     base = expr.get('base')
@@ -311,6 +321,8 @@ def check_exprs(schema):
         expr = expr_elem['expr']
         if expr.has_key('union'):
             check_union(expr, expr_elem['info'])
+        if expr.has_key('event'):
+            check_event(expr, expr_elem['info'])
 
 def parse_schema(input_file):
     try: