[FFmpeg-cvslog] avcodec/bitstream_filter: make av_register_bitstream_filter() thread safe

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Sat Jun 29 03:39:03 2013 +0200| [b36b5edb8fea33ebcacc0b77ce412372dd9f79e4] | committer: Michael Niedermayer

avcodec/bitstream_filter: make av_register_bitstream_filter() thread safe

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b36b5edb8fea33ebcacc0b77ce412372dd9f79e4
---

 libavcodec/bitstream_filter.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/libavcodec/bitstream_filter.c b/libavcodec/bitstream_filter.c
index 328a9f6..dd10531 100644
--- a/libavcodec/bitstream_filter.c
+++ b/libavcodec/bitstream_filter.c
@@ -21,6 +21,7 @@
 #include <string.h>
 
 #include "avcodec.h"
+#include "libavutil/atomic.h"
 #include "libavutil/mem.h"
 
 static AVBitStreamFilter *first_bitstream_filter= NULL;
@@ -31,8 +32,9 @@ AVBitStreamFilter *av_bitstream_filter_next(AVBitStreamFilter *f){
 }
 
 void av_register_bitstream_filter(AVBitStreamFilter *bsf){
-    bsf->next = first_bitstream_filter;
-    first_bitstream_filter= bsf;
+    do {
+        bsf->next = first_bitstream_filter;
+    } while(bsf->next != avpriv_atomic_ptr_cas((void * volatile *)&first_bitstream_filter, bsf->next, bsf));
 }
 
 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name){