ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinha...@gmail.com> | Wed Dec 2 00:10:13 2020 +0100| [6a94afbd5bf4aa3ccab12f038e8bbae7ef3973c0] | committer: Andreas Rheinhardt
avcodec/snow: Use ff_thread_once() in ff_snow_common_init() ff_snow_common_init() currently initializes static data every time it is invoked; given that both the Snow encoder and decoder have the FF_CODEC_CAP_INIT_THREADSAFE flag set, this can lead to data races (and therefore undefined behaviour) even though all threads write the same values. This commit fixes this by using ff_thread_once() for the initializations. Reviewed-by: Michael Niedermayer <mich...@niedermayer.cc> Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=6a94afbd5bf4aa3ccab12f038e8bbae7ef3973c0 --- libavcodec/snow.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/libavcodec/snow.c b/libavcodec/snow.c index 066efc5171..bb65a6f43f 100644 --- a/libavcodec/snow.c +++ b/libavcodec/snow.c @@ -21,6 +21,7 @@ #include "libavutil/intmath.h" #include "libavutil/log.h" #include "libavutil/opt.h" +#include "libavutil/thread.h" #include "avcodec.h" #include "me_cmp.h" #include "snow_dwt.h" @@ -427,10 +428,19 @@ mca( 8, 0,8) mca( 0, 8,8) mca( 8, 8,8) +static av_cold void snow_static_init(void) +{ + for (int i = 0; i < MAX_REF_FRAMES; i++) + for (int j = 0; j < MAX_REF_FRAMES; j++) + ff_scale_mv_ref[i][j] = 256 * (i + 1) / (j + 1); + init_qexp(); +} + av_cold int ff_snow_common_init(AVCodecContext *avctx){ + static AVOnce init_static_once = AV_ONCE_INIT; SnowContext *s = avctx->priv_data; int width, height; - int i, j; + int i; s->avctx= avctx; s->max_ref_frames=1; //just make sure it's not an invalid value in case of no initial keyframe @@ -480,8 +490,6 @@ av_cold int ff_snow_common_init(AVCodecContext *avctx){ mcfh(0, 8) mcfh(8, 8) - init_qexp(); - // dec += FFMAX(s->chroma_h_shift, s->chroma_v_shift); width= s->avctx->width; @@ -495,8 +503,6 @@ av_cold int ff_snow_common_init(AVCodecContext *avctx){ return AVERROR(ENOMEM); for(i=0; i<MAX_REF_FRAMES; i++) { - for(j=0; j<MAX_REF_FRAMES; j++) - ff_scale_mv_ref[i][j] = 256*(i+1)/(j+1); s->last_picture[i] = av_frame_alloc(); if (!s->last_picture[i]) return AVERROR(ENOMEM); @@ -507,6 +513,8 @@ av_cold int ff_snow_common_init(AVCodecContext *avctx){ if (!s->mconly_picture || !s->current_picture) return AVERROR(ENOMEM); + ff_thread_once(&init_static_once, snow_static_init); + return 0; } _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
