fic: set pict_type/key_frame after (instead of during) slice decoding.

This fixes a race condition that was already documented in the source
code, and is also reported by tsan in fate-fic-avi.
This commit is contained in:
Ronald S. Bultje 2017-03-28 19:52:07 -04:00
parent 9e2050b698
commit 73f863d751
1 changed files with 14 additions and 15 deletions

View File

@ -34,6 +34,7 @@ typedef struct FICThreadContext {
int slice_h;
int src_size;
int y_off;
int p_frame;
} FICThreadContext;
typedef struct FICContext {
@ -133,16 +134,13 @@ static void fic_idct_put(uint8_t *dst, int stride, int16_t *block)
}
}
static int fic_decode_block(FICContext *ctx, GetBitContext *gb,
uint8_t *dst, int stride, int16_t *block)
uint8_t *dst, int stride, int16_t *block, int *is_p)
{
int i, num_coeff;
/* Is it a skip block? */
if (get_bits1(gb)) {
/* This is a P-frame. */
ctx->frame->key_frame = 0;
ctx->frame->pict_type = AV_PICTURE_TYPE_P;
*is_p = 1;
return 0;
}
@ -182,7 +180,8 @@ static int fic_decode_slice(AVCodecContext *avctx, void *tdata)
for (x = 0; x < (ctx->aligned_width >> !!p); x += 8) {
int ret;
if ((ret = fic_decode_block(ctx, &gb, dst + x, stride, tctx->block)) != 0)
if ((ret = fic_decode_block(ctx, &gb, dst + x, stride,
tctx->block, &tctx->p_frame)) != 0)
return ret;
}
@ -348,15 +347,6 @@ static int fic_decode_frame(AVCodecContext *avctx, void *data,
return AVERROR_INVALIDDATA;
}
/*
* Set the frametype to I initially. It will be set to P if the frame
* has any dependencies (skip blocks). There will be a race condition
* inside the slice decode function to set these, but we do not care.
* since they will only ever be set to 0/P.
*/
ctx->frame->key_frame = 1;
ctx->frame->pict_type = AV_PICTURE_TYPE_I;
/* Allocate slice data. */
av_fast_malloc(&ctx->slice_data, &ctx->slice_data_size,
nslices * sizeof(ctx->slice_data[0]));
@ -398,6 +388,15 @@ static int fic_decode_frame(AVCodecContext *avctx, void *data,
NULL, nslices, sizeof(ctx->slice_data[0]))) < 0)
return ret;
ctx->frame->key_frame = 1;
ctx->frame->pict_type = AV_PICTURE_TYPE_I;
for (slice = 0; slice < nslices; slice++) {
if (ctx->slice_data[slice].p_frame) {
ctx->frame->key_frame = 0;
ctx->frame->pict_type = AV_PICTURE_TYPE_P;
break;
}
}
av_frame_free(&ctx->final_frame);
ctx->final_frame = av_frame_clone(ctx->frame);
if (!ctx->final_frame) {