qapi: More robust conditions for when labels are needed

We were using regular expressions to see if ret included
any earlier text that emitted a 'goto out;' line, to decide
whether we needed to output an 'out:' label.  But this is
fragile, if the ret text can possibly combine more than one
generated function body, where the first function used a
goto but the second does not.  Change the code to just check
for the known conditions which cause an error check to be
needed.  Besides, it's slightly more efficient to use plain
checks than regular expression searching.

No change to generated code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-4-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

diff --git a/scripts/qapi-commands.py b/scripts/qapi-commands.py
index 43a893b4eb0a872aa47a14de31fb93651c41fc71..561e47a42be35db3ced73f2ffa6b4105dc632acd 100644 (file)
--- a/scripts/qapi-commands.py
+++ b/scripts/qapi-commands.py
@@ -175,7 +175,9 @@ def gen_marshal(name, arg_type, ret_type):
     ret += gen_marshal_input_visit(arg_type)
     ret += gen_call(name, arg_type, ret_type)
 
-    if re.search('^ *goto out;', ret, re.MULTILINE):
+    # 'goto out' produced by gen_marshal_input_visit->gen_visit_fields()
+    # for each arg_type member, and by gen_call() for ret_type
+    if (arg_type and arg_type.members) or ret_type:
         ret += mcgen('''
 
 out:

diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index d0759d739a1fe4328c8c7c1f4c265aed49bb5954..2dc3aed220bb6671dbf37a9144e8eeec9b449a8d 100644 (file)
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -87,7 +87,8 @@ static void visit_type_%(c_name)s_fields(Visitor *v, %(c_name)s **obj, Error **e
 
     ret += gen_visit_fields(members, prefix='(*obj)->')
 
-    if re.search('^ *goto out;', ret, re.MULTILINE):
+    # 'goto out' produced for base, and by gen_visit_fields() for each member
+    if base or members:
         ret += mcgen('''
 
 out: