[FFmpeg-cvslog] avcodec/proresdec2: Constify slice threads' ptr to main context

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Sat Jul 23 06:11:35 2022 +0200| [0eae123dbd610b4ad371c6ebfc41a9d5b56abec8] | committer: Andreas Rheinhardt

avcodec/proresdec2: Constify slice threads' ptr to main context

Modifying the main context from a slice thread is (usually)
a data race, so it must not happen. So only use a pointer to const
to access the main context.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=0eae123dbd610b4ad371c6ebfc41a9d5b56abec8
---

 libavcodec/proresdec2.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavcodec/proresdec2.c b/libavcodec/proresdec2.c
index 01e650a650..659f9ff16b 100644
--- a/libavcodec/proresdec2.c
+++ b/libavcodec/proresdec2.c
@@ -500,7 +500,7 @@ static const uint8_t lev_to_cb[10] = { 0x04, 0x0A, 0x05, 0x06, 0x04, 0x28, 0x28,
 static av_always_inline int decode_ac_coeffs(AVCodecContext *avctx, GetBitContext *gb,
                                              int16_t *out, int blocks_per_slice)
 {
-    ProresContext *ctx = avctx->priv_data;
+    const ProresContext *ctx = avctx->priv_data;
     int block_mask, sign;
     unsigned pos, run, level;
     int max_coeffs, i, bits_left;
@@ -545,7 +545,7 @@ static int decode_slice_luma(AVCodecContext *avctx, SliceContext *slice,
                              const uint8_t *buf, unsigned buf_size,
                              const int16_t *qmat)
 {
-    ProresContext *ctx = avctx->priv_data;
+    const ProresContext *ctx = avctx->priv_data;
     LOCAL_ALIGNED_32(int16_t, blocks, [8*4*64]);
     int16_t *block;
     GetBitContext gb;
@@ -611,7 +611,7 @@ static int decode_slice_chroma(AVCodecContext *avctx, SliceContext *slice,
 /**
  * Decode alpha slice plane.
  */
-static void decode_slice_alpha(ProresContext *ctx,
+static void decode_slice_alpha(const ProresContext *ctx,
                                uint16_t *dst, int dst_stride,
                                const uint8_t *buf, int buf_size,
                                int blocks_per_slice)
@@ -643,7 +643,7 @@ static void decode_slice_alpha(ProresContext *ctx,
 
 static int decode_slice_thread(AVCodecContext *avctx, void *arg, int jobnr, int threadnr)
 {
-    ProresContext *ctx = avctx->priv_data;
+    const ProresContext *ctx = avctx->priv_data;
     SliceContext *slice = &ctx->slices[jobnr];
     const uint8_t *buf = slice->data;
     AVFrame *pic = ctx->frame;