[Qemu-devel] [PATCH 2/9] qapi: input visiter, don't always allocate memory for structs

[Michael Roth <mdroth@linux.vnet.ibm.com>]

Sometimes we have anonymous nested structs rather than references. In
these cases we call visit_start_struct() primarilly to push the nested
qobject onto the stack, and specify a NULL obj value to avoid doing any
memory allocation. So add a simple check for this NULL value.

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qapi/qmp-input-visiter.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/qapi/qmp-input-visiter.c b/qapi/qmp-input-visiter.c
index 53379fd..4bae85e 100644
--- a/qapi/qmp-input-visiter.c
+++ b/qapi/qmp-input-visiter.c
@@ -75,7 +75,9 @@ static void qmp_input_start_struct(Visiter *v, void **obj, const char *kind, con
 
     qmp_input_push(qiv, qobj);
 
-    *obj = qemu_mallocz(QAPI_OBJECT_SIZE);
+    if (obj) {
+        *obj = qemu_mallocz(QAPI_OBJECT_SIZE);
+    }
 }
 
 static void qmp_input_end_struct(Visiter *v, Error **errp)
-- 
1.7.0.4