From ed19974e25a6bf318a3ef2c3c86afe2369f56def Mon Sep 17 00:00:00 2001
From: Wim Taymans <wim.taymans@collabora.co.uk>
Date: Wed, 3 Oct 2012 13:45:22 +0200
Subject: [PATCH] meta: do metadata registration threadsafe

We need to use g_once to register the metadata implementations
only once.

See https://bugzilla.gnome.org/show_bug.cgi?id=685332
---
 docs/pwg/advanced-allocation.xml | 5 +++--
 libs/gst/net/gstnetaddressmeta.c | 5 +++--
 tests/check/gst/gstmeta.c        | 5 +++--
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/docs/pwg/advanced-allocation.xml b/docs/pwg/advanced-allocation.xml
index a8c34be9d0..625e76ee85 100644
--- a/docs/pwg/advanced-allocation.xml
+++ b/docs/pwg/advanced-allocation.xml
@@ -453,13 +453,14 @@ my_example_meta_get_info (void)
 {
   static const GstMetaInfo *meta_info = NULL;
 
-  if (meta_info == NULL) {
-    meta_info = gst_meta_register (MY_EXAMPLE_META_API_TYPE,
+  if (g_once_init_enter (&meta_info)) {
+    const GstMetaInfo *mi = gst_meta_register (MY_EXAMPLE_META_API_TYPE,
         "MyExampleMeta",
         sizeof (MyExampleMeta),
         my_example_meta_init,
         my_example_meta_free,
         my_example_meta_transform);
+    g_once_init_leave (&meta_info, mi);
   }
   return meta_info;
 }
diff --git a/libs/gst/net/gstnetaddressmeta.c b/libs/gst/net/gstnetaddressmeta.c
index af869aea40..5b87afe085 100644
--- a/libs/gst/net/gstnetaddressmeta.c
+++ b/libs/gst/net/gstnetaddressmeta.c
@@ -82,12 +82,13 @@ gst_net_address_meta_get_info (void)
 {
   static const GstMetaInfo *meta_info = NULL;
 
-  if (meta_info == NULL) {
-    meta_info = gst_meta_register (GST_NET_ADDRESS_META_API_TYPE,
+  if (g_once_init_enter (&meta_info)) {
+    const GstMetaInfo *mi = gst_meta_register (GST_NET_ADDRESS_META_API_TYPE,
         "GstNetAddressMeta",
         sizeof (GstNetAddressMeta),
         net_address_meta_init,
         net_address_meta_free, net_address_meta_transform);
+    g_once_init_leave (&meta_info, mi);
   }
   return meta_info;
 }
diff --git a/tests/check/gst/gstmeta.c b/tests/check/gst/gstmeta.c
index 73b5d56c52..0f2355b8da 100644
--- a/tests/check/gst/gstmeta.c
+++ b/tests/check/gst/gstmeta.c
@@ -139,11 +139,12 @@ gst_meta_test_get_info (void)
 {
   static const GstMetaInfo *meta_test_info = NULL;
 
-  if (meta_test_info == NULL) {
-    meta_test_info = gst_meta_register (GST_META_TEST_API_TYPE,
+  if (g_once_init_enter (&meta_test_info)) {
+    const GstMetaInfo *mi = gst_meta_register (GST_META_TEST_API_TYPE,
         "GstMetaTest",
         sizeof (GstMetaTest),
         test_init_func, test_free_func, test_transform_func);
+    g_once_init_leave (&meta_test_info, mi);
   }
   return meta_test_info;
 }