diff --git a/libavformat/format.c b/libavformat/format.c index c1be85983a..ac9100b604 100644 --- a/libavformat/format.c +++ b/libavformat/format.c @@ -21,6 +21,7 @@ #include "avformat.h" #include "internal.h" +#include "libavutil/atomic.h" #include "libavutil/avstring.h" /** @@ -52,22 +53,18 @@ void av_register_input_format(AVInputFormat *format) { AVInputFormat **p = &first_iformat; - while (*p != NULL) - p = &(*p)->next; - - *p = format; format->next = NULL; + while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format)) + p = &(*p)->next; } void av_register_output_format(AVOutputFormat *format) { AVOutputFormat **p = &first_oformat; - while (*p != NULL) - p = &(*p)->next; - - *p = format; format->next = NULL; + while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format)) + p = &(*p)->next; } int av_match_ext(const char *filename, const char *extensions)