From 3a97180293149e5036da3067bd54258d866d16f0 Mon Sep 17 00:00:00 2001
From: lahiker42 <lahiker42@00440858-1255-0410-a3e6-75ea37f81c3a>
Date: Wed, 10 Feb 2010 18:04:17 +0000
Subject: [PATCH] optimziation

git-svn-id: https://protobuf-c.googlecode.com/svn/trunk@206 00440858-1255-0410-a3e6-75ea37f81c3a
---
 ChangeLog                          |  2 ++
 src/google/protobuf-c/protobuf-c.c | 25 ++++++++++++++++++-------
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1974d0a..74f0b02 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,8 @@
       - Add --disable-protoc to only build libprotobuf-c (daveb)
       - Bug fixes for protobuf_c_enum_descriptor_get_value_by_name()
         and protobuf_c_service_descriptor_get_method_by_name()
+      - if descriptor->message_init != NULL, use it from unpack()
+        as an optimization (daveb)
 
 0.12:
       - for field names which are reserved words, use the real name 
diff --git a/src/google/protobuf-c/protobuf-c.c b/src/google/protobuf-c/protobuf-c.c
index 11e91d2..26c4b89 100644
--- a/src/google/protobuf-c/protobuf-c.c
+++ b/src/google/protobuf-c/protobuf-c.c
@@ -1448,11 +1448,17 @@ parse_member (ScannedMember *scanned_member,
   return 0;
 }
 
-static inline void
-setup_default_values (ProtobufCMessage *message)
+
+/* TODO: expose/use this function if desc->message_init==NULL 
+   (which occurs for old code, and may be useful for certain
+   programatic techniques for generating descriptors). */
+void
+protobuf_c_message_init_generic (const ProtobufCMessageDescriptor *desc,
+                                 ProtobufCMessage *message)
 {
-  const ProtobufCMessageDescriptor *desc = message->descriptor;
   unsigned i;
+  memset (message, 0, desc->sizeof_message);
+  message->descriptor = desc;
   for (i = 0; i < desc->n_fields; i++)
     if (desc->fields[i].default_value != NULL
      && desc->fields[i].label != PROTOBUF_C_LABEL_REPEATED)
@@ -1548,10 +1554,15 @@ protobuf_c_message_unpack         (const ProtobufCMessageDescriptor *desc,
   DO_ALLOC (rv, allocator, desc->sizeof_message, return NULL);
   scanned_member_slabs[0] = first_member_slab;
 
-  memset (rv, 0, desc->sizeof_message);
-  rv->descriptor = desc;
-
-  setup_default_values (rv);
+  /* Generated code always defines "message_init".
+     However, we provide a fallback for (1) users of old protobuf-c
+     generated-code that do not provide the function,
+     and (2) descriptors constructed from some other source
+     (most likely, direct construction from the .proto file) */
+  if (desc->message_init != NULL)
+    protobuf_c_message_init (desc, rv);
+  else
+    protobuf_c_message_init_generic (desc, rv);
 
   while (rem > 0)
     {