[FFmpeg-devel] [PATCH 10/18] cbs: Remove superfluous checks for ff_cbs_delete_unit

[Andreas Rheinhardt]

ff_cbs_delete_unit never fails if the index of the unit to delete is
valid; document this behaviour explicitly and remove the checks for
whether ff_cbs_delete_unit failed, because all the callers of
ff_cbs_delete_unit already make sure that the index is valid.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
---
Several callers already ignored to check the return value.

 libavcodec/av1_metadata_bsf.c       | 9 ++-------
 libavcodec/cbs.h                    | 2 ++
 libavcodec/h264_metadata_bsf.c      | 7 +------
 libavcodec/h264_redundant_pps_bsf.c | 4 +---
 4 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/libavcodec/av1_metadata_bsf.c b/libavcodec/av1_metadata_bsf.c
index 842b80c201..dafddced63 100644
--- a/libavcodec/av1_metadata_bsf.c
+++ b/libavcodec/av1_metadata_bsf.c
@@ -161,13 +161,8 @@ static int av1_metadata_filter(AVBSFContext *bsf, AVPacket *pkt)
 
     if (ctx->delete_padding) {
         for (i = frag->nb_units - 1; i >= 0; i--) {
-            if (frag->units[i].type == AV1_OBU_PADDING) {
-                err = ff_cbs_delete_unit(ctx->cbc, frag, i);
-                if (err < 0) {
-                    av_log(bsf, AV_LOG_ERROR, "Failed to delete Padding OBU.\n");
-                    goto fail;
-                }
-            }
+            if (frag->units[i].type == AV1_OBU_PADDING)
+                ff_cbs_delete_unit(ctx->cbc, frag, i);
         }
     }
 
diff --git a/libavcodec/cbs.h b/libavcodec/cbs.h
index 5260a39c63..e1e6055ceb 100644
--- a/libavcodec/cbs.h
+++ b/libavcodec/cbs.h
@@ -380,6 +380,8 @@ int ff_cbs_insert_unit_data(CodedBitstreamContext *ctx,
 
 /**
  * Delete a unit from a fragment and free all memory it uses.
+ *
+ * Never returns failure if position is >= 0 and < frag->nb_units.
  */
 int ff_cbs_delete_unit(CodedBitstreamContext *ctx,
                        CodedBitstreamFragment *frag,
diff --git a/libavcodec/h264_metadata_bsf.c b/libavcodec/h264_metadata_bsf.c
index f7ca1f0f09..d05b75be14 100644
--- a/libavcodec/h264_metadata_bsf.c
+++ b/libavcodec/h264_metadata_bsf.c
@@ -428,12 +428,7 @@ static int h264_metadata_filter(AVBSFContext *bsf, AVPacket *pkt)
         for (i = au->nb_units - 1; i >= 0; i--) {
             if (au->units[i].type == H264_NAL_FILLER_DATA) {
                 // Filler NAL units.
-                err = ff_cbs_delete_unit(ctx->cbc, au, i);
-                if (err < 0) {
-                    av_log(bsf, AV_LOG_ERROR, "Failed to delete "
-                           "filler NAL.\n");
-                    goto fail;
-                }
+                ff_cbs_delete_unit(ctx->cbc, au, i);
                 continue;
             }
 
diff --git a/libavcodec/h264_redundant_pps_bsf.c b/libavcodec/h264_redundant_pps_bsf.c
index db8717d69a..8526b5b4c4 100644
--- a/libavcodec/h264_redundant_pps_bsf.c
+++ b/libavcodec/h264_redundant_pps_bsf.c
@@ -95,9 +95,7 @@ static int h264_redundant_pps_filter(AVBSFContext *bsf, AVPacket *out)
             if (!au_has_sps) {
                 av_log(bsf, AV_LOG_VERBOSE, "Deleting redundant PPS "
                        "at %"PRId64".\n", in->pts);
-                err = ff_cbs_delete_unit(ctx->input, au, i);
-                if (err < 0)
-                    goto fail;
+                ff_cbs_delete_unit(ctx->input, au, i);
             }
         }
         if (nal->type == H264_NAL_SLICE ||
-- 
2.21.0