From 316fc7443b05f8c8b494443f2dfe590434796902 Mon Sep 17 00:00:00 2001 From: Janne Grunau Date: Tue, 31 Jan 2012 15:40:11 +0000 Subject: [PATCH] avcodec: Add av_fast_padded_malloc(). MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Wrapper around av_fast_malloc() that keeps FF_INPUT_BUFFER_PADDING_SIZE zero-padded bytes at the end of the used buffer. Based on a patch by Reimar Döffinger . --- doc/APIchanges | 5 +++++ libavcodec/avcodec.h | 9 +++++++++ libavcodec/utils.c | 13 +++++++++++++ 3 files changed, 27 insertions(+) diff --git a/doc/APIchanges b/doc/APIchanges index 0d4cb596a7..df55c0a732 100644 --- a/doc/APIchanges +++ b/doc/APIchanges @@ -13,6 +13,11 @@ libavutil: 2011-04-18 API changes, most recent first: +2012-02-01 - xxxxxxx - lavc 54.01.0 + Add av_fast_padded_malloc() as alternative for av_realloc() when aligned + memory is required. The buffer will always have FF_INPUT_BUFFER_PADDING_SIZE + zero-padded bytes at the end. + 2012-01-31 - xxxxxxx - lavf 54.01.0 Add avformat_get_riff_video_tags() and avformat_get_riff_audio_tags(). diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h index c70eb852a8..fcbb68ad60 100644 --- a/libavcodec/avcodec.h +++ b/libavcodec/avcodec.h @@ -4071,6 +4071,15 @@ void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size); void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size); /** + * Allocate a buffer with padding, reusing the given one if large enough. + * + * Same behaviour av_fast_malloc but the buffer has additional + * FF_INPUT_PADDING_SIZE at the end which will always memset to 0. + * + */ +void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size); + +/** * Copy image src to dst. Wraps av_picture_data_copy() above. */ void av_picture_copy(AVPicture *dst, const AVPicture *src, diff --git a/libavcodec/utils.c b/libavcodec/utils.c index fa609534a5..34eff0031a 100644 --- a/libavcodec/utils.c +++ b/libavcodec/utils.c @@ -80,6 +80,19 @@ void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size) *size= min_size; } +void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size) +{ + void **p = ptr; + if (min_size > SIZE_MAX - FF_INPUT_BUFFER_PADDING_SIZE) { + av_freep(p); + *size = 0; + return; + } + av_fast_malloc(p, size, min_size + FF_INPUT_BUFFER_PADDING_SIZE); + if (*size) + memset((uint8_t *)*p + min_size, 0, FF_INPUT_BUFFER_PADDING_SIZE); +} + /* encoder management */ static AVCodec *first_avcodec = NULL; -- 2.11.0