From 49f10c9cb185315a41ee06cf7c4c55abfd470c7a Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 8 Dec 2013 02:29:28 +0100 Subject: avformat/format: av_register_output_format() and av_register_intput_format() that work in O(1) time Reviewed-by: Stefano Sabatini Signed-off-by: Michael Niedermayer --- libavformat/format.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'libavformat/format.c') diff --git a/libavformat/format.c b/libavformat/format.c index 36c0131c12..95060f373d 100644 --- a/libavformat/format.c +++ b/libavformat/format.c @@ -33,6 +33,9 @@ static AVInputFormat *first_iformat = NULL; /** head of registered output format linked list */ static AVOutputFormat *first_oformat = NULL; +static AVInputFormat **last_iformat = &first_iformat; +static AVOutputFormat **last_oformat = &first_oformat; + AVInputFormat *av_iformat_next(AVInputFormat *f) { if (f) @@ -51,20 +54,22 @@ AVOutputFormat *av_oformat_next(AVOutputFormat *f) void av_register_input_format(AVInputFormat *format) { - AVInputFormat **p = &first_iformat; + AVInputFormat **p = last_iformat; format->next = NULL; while(*p || avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format)) p = &(*p)->next; + last_iformat = &format->next; } void av_register_output_format(AVOutputFormat *format) { - AVOutputFormat **p = &first_oformat; + AVOutputFormat **p = last_oformat; format->next = NULL; while(*p || avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format)) p = &(*p)->next; + last_oformat = &format->next; } int av_match_ext(const char *filename, const char *extensions) -- cgit v1.2.3