avcodec/cbs: Use RefStruct-API for unit content

This avoids allocations and error checks etc. as well
as duplicate pointer lists in the CodedBitstreamFooContexts.
It also avoids casting const away for use as opaque,
as the RefStruct API supports const opaques.

The fact that some of the units are not refcounted
(i.e. they are sometimes part of an encoding context
like VAAPIEncodeH264Context) meant that CodedBitstreamUnit
still contains two pointers, one to the content
and another ownership pointer, replacing the AVBufferRef* pointer.

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

libavcodec/av1dec.c

@@ -37,6 +37,7 @@
 #include "internal.h"
 #include "hwconfig.h"
 #include "profiles.h"
+#include "refstruct.h"
 #include "thread.h"
 
 /**< same with Div_Lut defined in spec 7.11.3.7 */
@@ -641,7 +642,7 @@ static void av1_frame_unref(AVCodecContext *avctx, AV1Frame *f)
     ff_thread_release_buffer(avctx, f->f);
     av_buffer_unref(&f->hwaccel_priv_buf);
     f->hwaccel_picture_private = NULL;
-    av_buffer_unref(&f->header_ref);
+    ff_refstruct_unref(&f->header_ref);
     f->raw_frame_header = NULL;
     f->spatial_id = f->temporal_id = 0;
     memset(f->skip_mode_frame_idx, 0,
@@ -654,9 +655,7 @@ static int av1_frame_ref(AVCodecContext *avctx, AV1Frame *dst, const AV1Frame *s
 {
     int ret;
 
-    ret = av_buffer_replace(&dst->header_ref, src->header_ref);
-    if (ret < 0)
-        return ret;
+    ff_refstruct_replace(&dst->header_ref, src->header_ref);
 
     dst->raw_frame_header = src->raw_frame_header;
 
@@ -712,10 +711,10 @@ static av_cold int av1_decode_free(AVCodecContext *avctx)
     av1_frame_unref(avctx, &s->cur_frame);
     av_frame_free(&s->cur_frame.f);
 
-    av_buffer_unref(&s->seq_ref);
-    av_buffer_unref(&s->header_ref);
-    av_buffer_unref(&s->cll_ref);
-    av_buffer_unref(&s->mdcv_ref);
+    ff_refstruct_unref(&s->seq_ref);
+    ff_refstruct_unref(&s->header_ref);
+    ff_refstruct_unref(&s->cll_ref);
+    ff_refstruct_unref(&s->mdcv_ref);
     av_freep(&s->tile_group_info);
 
     while (s->itut_t35_fifo && av_fifo_read(s->itut_t35_fifo, &itut_t35, 1) >= 0)
@@ -1160,9 +1159,7 @@ static int get_current_frame(AVCodecContext *avctx)
 
     av1_frame_unref(avctx, &s->cur_frame);
 
-    s->cur_frame.header_ref = av_buffer_ref(s->header_ref);
-    if (!s->cur_frame.header_ref)
-        return AVERROR(ENOMEM);
+    s->cur_frame.header_ref = ff_refstruct_ref(s->header_ref);
 
     s->cur_frame.raw_frame_header = s->raw_frame_header;
 
@@ -1214,12 +1211,7 @@ static int av1_receive_frame_internal(AVCodecContext *avctx, AVFrame *frame)
 
         switch (unit->type) {
         case AV1_OBU_SEQUENCE_HEADER:
-            av_buffer_unref(&s->seq_ref);
-            s->seq_ref = av_buffer_ref(unit->content_ref);
-            if (!s->seq_ref) {
-                ret = AVERROR(ENOMEM);
-                goto end;
-            }
+            ff_refstruct_replace(&s->seq_ref, unit->content_ref);
 
             s->raw_seq = &obu->obu.sequence_header;
 
@@ -1264,12 +1256,7 @@ static int av1_receive_frame_internal(AVCodecContext *avctx, AVFrame *frame)
                 goto end;
             }
 
-            av_buffer_unref(&s->header_ref);
-            s->header_ref = av_buffer_ref(unit->content_ref);
-            if (!s->header_ref) {
-                ret = AVERROR(ENOMEM);
-                goto end;
-            }
+            ff_refstruct_replace(&s->header_ref, unit->content_ref);
 
             if (unit->type == AV1_OBU_FRAME)
                 s->raw_frame_header = &obu->obu.frame.header;
@@ -1356,23 +1343,11 @@ static int av1_receive_frame_internal(AVCodecContext *avctx, AVFrame *frame)
         case AV1_OBU_METADATA:
             switch (obu->obu.metadata.metadata_type) {
             case AV1_METADATA_TYPE_HDR_CLL:
-                av_buffer_unref(&s->cll_ref);
-                s->cll_ref = av_buffer_ref(unit->content_ref);
-                if (!s->cll_ref) {
-                    s->cll = NULL;
-                    ret = AVERROR(ENOMEM);
-                    goto end;
-                }
+                ff_refstruct_replace(&s->cll_ref, unit->content_ref);
                 s->cll = &obu->obu.metadata.metadata.hdr_cll;
                 break;
             case AV1_METADATA_TYPE_HDR_MDCV:
-                av_buffer_unref(&s->mdcv_ref);
-                s->mdcv_ref = av_buffer_ref(unit->content_ref);
-                if (!s->mdcv_ref) {
-                    s->mdcv = NULL;
-                    ret = AVERROR(ENOMEM);
-                    goto end;
-                }
+                ff_refstruct_replace(&s->mdcv_ref, unit->content_ref);
                 s->mdcv = &obu->obu.metadata.metadata.hdr_mdcv;
                 break;
             case AV1_METADATA_TYPE_ITUT_T35: {

libavcodec/av1dec.h

@@ -38,7 +38,7 @@ typedef struct AV1Frame {
     AVBufferRef *hwaccel_priv_buf;
     void *hwaccel_picture_private;
 
-    AVBufferRef *header_ref;
+    AV1RawOBU *header_ref; ///< RefStruct reference backing raw_frame_header.
     AV1RawFrameHeader *raw_frame_header;
 
     int temporal_id;
@@ -71,15 +71,15 @@ typedef struct AV1DecContext {
     CodedBitstreamFragment current_obu;
     AVPacket *pkt;
 
-    AVBufferRef *seq_ref;
+    AV1RawOBU *seq_ref;    ///< RefStruct reference backing raw_seq
     AV1RawSequenceHeader *raw_seq;
-    AVBufferRef *header_ref;
+    AV1RawOBU *header_ref; ///< RefStruct reference backing raw_frame_header
     AV1RawFrameHeader *raw_frame_header;
     TileGroupInfo *tile_group_info;
 
-    AVBufferRef *cll_ref;
+    AV1RawOBU *cll_ref;    ///< RefStruct reference backing cll
     AV1RawMetadataHDRCLL *cll;
-    AVBufferRef *mdcv_ref;
+    AV1RawOBU *mdcv_ref;   ///< RefStruct reference backing mdcv
     AV1RawMetadataHDRMDCV *mdcv;
     AVFifo *itut_t35_fifo;
 

libavcodec/cbs.c

@@ -28,6 +28,7 @@
 #include "avcodec.h"
 #include "cbs.h"
 #include "cbs_internal.h"
+#include "refstruct.h"
 
 
 static const CodedBitstreamType *const cbs_type_table[] = {
@@ -152,7 +153,7 @@ av_cold void ff_cbs_close(CodedBitstreamContext **ctx_ptr)
 
 static void cbs_unit_uninit(CodedBitstreamUnit *unit)
 {
-    av_buffer_unref(&unit->content_ref);
+    ff_refstruct_unref(&unit->content_ref);
     unit->content = NULL;
 
     av_buffer_unref(&unit->data_ref);
@@ -200,7 +201,7 @@ static int cbs_read_fragment_content(CodedBitstreamContext *ctx,
                 continue;
         }
 
-        av_buffer_unref(&unit->content_ref);
+        ff_refstruct_unref(&unit->content_ref);
         unit->content = NULL;
 
         av_assert0(unit->data && unit->data_ref);
@@ -214,7 +215,7 @@ static int cbs_read_fragment_content(CodedBitstreamContext *ctx,
             av_log(ctx->log_ctx, AV_LOG_VERBOSE,
                    "Skipping decomposition of unit %d "
                    "(type %"PRIu32").\n", i, unit->type);
-            av_buffer_unref(&unit->content_ref);
+            ff_refstruct_unref(&unit->content_ref);
             unit->content = NULL;
         } else if (err < 0) {
             av_log(ctx->log_ctx, AV_LOG_ERROR, "Failed to read unit %d "
@@ -776,28 +777,22 @@ int ff_cbs_insert_unit_content(CodedBitstreamFragment *frag,
                                int position,
                                CodedBitstreamUnitType type,
                                void *content,
-                               AVBufferRef *content_buf)
+                               void *content_ref)
 {
     CodedBitstreamUnit *unit;
-    AVBufferRef *content_ref;
     int err;
 
     if (position == -1)
         position = frag->nb_units;
     av_assert0(position >= 0 && position <= frag->nb_units);
 
-    if (content_buf) {
-        content_ref = av_buffer_ref(content_buf);
-        if (!content_ref)
-            return AVERROR(ENOMEM);
-    } else {
-        content_ref = NULL;
-    }
-
     err = cbs_insert_unit(frag, position);
-    if (err < 0) {
-        av_buffer_unref(&content_ref);
+    if (err < 0)
         return err;
+
+    if (content_ref) {
+        // Create our own reference out of the user-supplied one.
+        content_ref = ff_refstruct_ref(content_ref);
     }
 
     unit = &frag->units[position];
@@ -871,15 +866,14 @@ void ff_cbs_delete_unit(CodedBitstreamFragment *frag,
                 (frag->nb_units - position) * sizeof(*frag->units));
 }
 
-static void cbs_default_free_unit_content(void *opaque, uint8_t *data)
+static void cbs_default_free_unit_content(FFRefStructOpaque opaque, void *content)
 {
-    const CodedBitstreamUnitTypeDescriptor *desc = opaque;
+    const CodedBitstreamUnitTypeDescriptor *desc = opaque.c;
 
     for (int i = 0; i < desc->type.ref.nb_offsets; i++) {
-        void **ptr = (void**)(data + desc->type.ref.offsets[i]);
+        void **ptr = (void**)((char*)content + desc->type.ref.offsets[i]);
         av_buffer_unref((AVBufferRef**)(ptr + 1));
     }
-    av_free(data);
 }
 
 static const CodedBitstreamUnitTypeDescriptor
@@ -910,6 +904,15 @@ static const CodedBitstreamUnitTypeDescriptor
     return NULL;
 }
 
+static void *cbs_alloc_content(const CodedBitstreamUnitTypeDescriptor *desc)
+{
+    return ff_refstruct_alloc_ext_c(desc->content_size, 0,
+                                    (FFRefStructOpaque){ .c = desc },
+                                    desc->content_type == CBS_CONTENT_TYPE_COMPLEX
+                                            ? desc->type.complex.content_free
+                                            : cbs_default_free_unit_content);
+}
+
 int ff_cbs_alloc_unit_content(CodedBitstreamContext *ctx,
                               CodedBitstreamUnit *unit)
 {
@@ -921,27 +924,17 @@ int ff_cbs_alloc_unit_content(CodedBitstreamContext *ctx,
     if (!desc)
         return AVERROR(ENOSYS);
 
-    unit->content = av_mallocz(desc->content_size);
-    if (!unit->content)
+    unit->content_ref = cbs_alloc_content(desc);
+    if (!unit->content_ref)
         return AVERROR(ENOMEM);
-
-    unit->content_ref =
-        av_buffer_create(unit->content, desc->content_size,
-                         desc->content_type == CBS_CONTENT_TYPE_COMPLEX
-                                            ? desc->type.complex.content_free
-                                            : cbs_default_free_unit_content,
-                         (void*)desc, 0);
-    if (!unit->content_ref) {
-        av_freep(&unit->content);
-        return AVERROR(ENOMEM);
-    }
+    unit->content = unit->content_ref;
 
     return 0;
 }
 
-static int cbs_clone_internal_refs_unit_content(AVBufferRef **clone_ref,
-                                                const CodedBitstreamUnit *unit,
-                                                const CodedBitstreamUnitTypeDescriptor *desc)
+static int cbs_clone_noncomplex_unit_content(void **clonep,
+                                             const CodedBitstreamUnit *unit,
+                                             const CodedBitstreamUnitTypeDescriptor *desc)
 {
     const uint8_t *src;
     uint8_t *copy;
@@ -950,9 +943,15 @@ static int cbs_clone_internal_refs_unit_content(AVBufferRef **clone_ref,
     av_assert0(unit->content);
     src = unit->content;
 
-    copy = av_memdup(src, desc->content_size);
+    copy = cbs_alloc_content(desc);
     if (!copy)
         return AVERROR(ENOMEM);
+    memcpy(copy, src, desc->content_size);
+    for (int i = 0; i < desc->type.ref.nb_offsets; i++) {
+        void **ptr = (void**)(copy + desc->type.ref.offsets[i]);
+        /* Zero all the AVBufferRefs as they are owned by src. */
+        *(ptr + 1) = NULL;
+    }
 
     for (i = 0; i < desc->type.ref.nb_offsets; i++) {
         const uint8_t *const *src_ptr = (const uint8_t* const*)(src + desc->type.ref.offsets[i]);
@@ -978,22 +977,12 @@ static int cbs_clone_internal_refs_unit_content(AVBufferRef **clone_ref,
             goto fail;
         }
     }
-
-    *clone_ref = av_buffer_create(copy, desc->content_size,
-                                  cbs_default_free_unit_content,
-                                  (void*)desc, 0);
-    if (!*clone_ref) {
-        err = AVERROR(ENOMEM);
-        goto fail;
-    }
+    *clonep = copy;
 
     return 0;
 
 fail:
-    for (--i; i >= 0; i--)
-        av_buffer_unref((AVBufferRef**)(copy + desc->type.ref.offsets[i]));
-    av_freep(&copy);
-    *clone_ref = NULL;
+    ff_refstruct_unref(&copy);
     return err;
 }
 
@@ -1006,7 +995,7 @@ static int cbs_clone_unit_content(CodedBitstreamContext *ctx,
                                   CodedBitstreamUnit *unit)
 {
     const CodedBitstreamUnitTypeDescriptor *desc;
-    AVBufferRef *ref;
+    void *new_content;
     int err;
 
     desc = cbs_find_unit_type_desc(ctx, unit);
@@ -1015,13 +1004,13 @@ static int cbs_clone_unit_content(CodedBitstreamContext *ctx,
 
     switch (desc->content_type) {
     case CBS_CONTENT_TYPE_INTERNAL_REFS:
-        err = cbs_clone_internal_refs_unit_content(&ref, unit, desc);
+        err = cbs_clone_noncomplex_unit_content(&new_content, unit, desc);
         break;
 
     case CBS_CONTENT_TYPE_COMPLEX:
         if (!desc->type.complex.content_clone)
             return AVERROR_PATCHWELCOME;
-        err = desc->type.complex.content_clone(&ref, unit);
+        err = desc->type.complex.content_clone(&new_content, unit);
         break;
 
     default:
@@ -1031,8 +1020,8 @@ static int cbs_clone_unit_content(CodedBitstreamContext *ctx,
     if (err < 0)
         return err;
 
-    unit->content_ref = ref;
-    unit->content     = ref->data;
+    unit->content_ref = new_content;
+    unit->content     = new_content;
     return 0;
 }
 
@@ -1048,17 +1037,17 @@ int ff_cbs_make_unit_refcounted(CodedBitstreamContext *ctx,
 int ff_cbs_make_unit_writable(CodedBitstreamContext *ctx,
                               CodedBitstreamUnit *unit)
 {
-    AVBufferRef *ref = unit->content_ref;
+    void *ref = unit->content_ref;
     int err;
 
     av_assert0(unit->content);
-    if (ref && av_buffer_is_writable(ref))
+    if (ref && ff_refstruct_exclusive(ref))
         return 0;
 
     err = cbs_clone_unit_content(ctx, unit);
     if (err < 0)
         return err;
-    av_buffer_unref(&ref);
+    ff_refstruct_unref(&ref);
     return 0;
 }
 

libavcodec/cbs.h

@@ -106,10 +106,10 @@ typedef struct CodedBitstreamUnit {
      */
     void *content;
     /**
-     * If content is reference counted, a reference to the buffer containing
-     * content.  Null if content is not reference counted.
+     * If content is reference counted, a RefStruct reference backing content.
+     * NULL if content is not reference counted.
      */
-    AVBufferRef *content_ref;
+    void *content_ref;
 } CodedBitstreamUnit;
 
 /**
@@ -438,14 +438,16 @@ int ff_cbs_alloc_unit_content(CodedBitstreamContext *ctx,
 /**
  * Insert a new unit into a fragment with the given content.
  *
+ * If content_ref is supplied, it has to be a RefStruct reference
+ * backing content; the user keeps ownership of the supplied reference.
  * The content structure continues to be owned by the caller if
- * content_buf is not supplied.
+ * content_ref is not supplied.
  */
 int ff_cbs_insert_unit_content(CodedBitstreamFragment *frag,
                                int position,
                                CodedBitstreamUnitType type,
                                void *content,
-                               AVBufferRef *content_buf);
+                               void *content_ref);
 
 /**
  * Add a new unit to a fragment with the given data bitstream.

libavcodec/cbs_av1.c

@@ -24,6 +24,7 @@
 #include "cbs_internal.h"
 #include "cbs_av1.h"
 #include "defs.h"
+#include "refstruct.h"
 
 
 static int cbs_av1_read_uvlc(CodedBitstreamContext *ctx, GetBitContext *gbc,
@@ -869,12 +870,7 @@ static int cbs_av1_read_unit(CodedBitstreamContext *ctx,
                 priv->operating_point_idc = sequence_header->operating_point_idc[priv->operating_point];
             }
 
-            av_buffer_unref(&priv->sequence_header_ref);
-            priv->sequence_header = NULL;
-
-            priv->sequence_header_ref = av_buffer_ref(unit->content_ref);
-            if (!priv->sequence_header_ref)
-                return AVERROR(ENOMEM);
+            ff_refstruct_replace(&priv->sequence_header_ref, unit->content_ref);
             priv->sequence_header = &obu->obu.sequence_header;
         }
         break;
@@ -993,9 +989,7 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx,
     av1ctx = *priv;
 
     if (priv->sequence_header_ref) {
-        av1ctx.sequence_header_ref = av_buffer_ref(priv->sequence_header_ref);
-        if (!av1ctx.sequence_header_ref)
-            return AVERROR(ENOMEM);
+        av1ctx.sequence_header_ref = ff_refstruct_ref(priv->sequence_header_ref);
     }
 
     if (priv->frame_header_ref) {
@@ -1033,19 +1027,14 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx,
             if (err < 0)
                 goto error;
 
-            av_buffer_unref(&priv->sequence_header_ref);
+            ff_refstruct_unref(&priv->sequence_header_ref);
             priv->sequence_header = NULL;
 
             err = ff_cbs_make_unit_refcounted(ctx, unit);
             if (err < 0)
                 goto error;
 
-            priv->sequence_header_ref = av_buffer_ref(unit->content_ref);
-            if (!priv->sequence_header_ref) {
-                err = AVERROR(ENOMEM);
-                goto error;
-            }
-
+            priv->sequence_header_ref = ff_refstruct_ref(unit->content_ref);
             priv->sequence_header = &obu->obu.sequence_header;
         }
         break;
@@ -1149,7 +1138,7 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx,
     av_assert0(data_pos <= start_pos);
 
     if (8 * obu->obu_size > put_bits_left(pbc)) {
-        av_buffer_unref(&priv->sequence_header_ref);
+        ff_refstruct_unref(&priv->sequence_header_ref);
         av_buffer_unref(&priv->frame_header_ref);
         *priv = av1ctx;
 
@@ -1178,7 +1167,7 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx,
     err = 0;
 
 error:
-    av_buffer_unref(&av1ctx.sequence_header_ref);
+    ff_refstruct_unref(&av1ctx.sequence_header_ref);
     av_buffer_unref(&av1ctx.frame_header_ref);
 
     return err;
@@ -1230,13 +1219,13 @@ static void cbs_av1_close(CodedBitstreamContext *ctx)
 {
     CodedBitstreamAV1Context *priv = ctx->priv_data;
 
-    av_buffer_unref(&priv->sequence_header_ref);
+    ff_refstruct_unref(&priv->sequence_header_ref);
     av_buffer_unref(&priv->frame_header_ref);
 }
 
-static void cbs_av1_free_metadata(void *unit, uint8_t *content)
+static void cbs_av1_free_metadata(FFRefStructOpaque unused, void *content)
 {
-    AV1RawOBU *obu = (AV1RawOBU*)content;
+    AV1RawOBU *obu = content;
     AV1RawMetadata *md;
 
     av_assert0(obu->header.obu_type == AV1_OBU_METADATA);
@@ -1254,7 +1243,6 @@ static void cbs_av1_free_metadata(void *unit, uint8_t *content)
     default:
         av_buffer_unref(&md->metadata.unknown.payload_ref);
     }
-    av_free(content);
 }
 
 static const CodedBitstreamUnitTypeDescriptor cbs_av1_unit_types[] = {

libavcodec/cbs_av1.h

@@ -437,7 +437,8 @@ typedef struct CodedBitstreamAV1Context {
     const AVClass *class;
 
     AV1RawSequenceHeader *sequence_header;
-    AVBufferRef          *sequence_header_ref;
+    /** A RefStruct reference backing sequence_header. */
+    AV1RawOBU            *sequence_header_ref;
 
     int     seen_frame_header;
     AVBufferRef *frame_header_ref;

libavcodec/cbs_h264.h

@@ -407,10 +407,8 @@ typedef struct CodedBitstreamH264Context {
 
     // All currently available parameter sets.  These are updated when
     // any parameter set NAL unit is read/written with this context.
-    AVBufferRef *sps_ref[H264_MAX_SPS_COUNT];
-    AVBufferRef *pps_ref[H264_MAX_PPS_COUNT];
-    H264RawSPS *sps[H264_MAX_SPS_COUNT];
-    H264RawPPS *pps[H264_MAX_PPS_COUNT];
+    H264RawSPS *sps[H264_MAX_SPS_COUNT]; ///< RefStruct references
+    H264RawPPS *pps[H264_MAX_PPS_COUNT]; ///< RefStruct references
 
     // The currently active parameter sets.  These are updated when any
     // NAL unit refers to the relevant parameter set.  These pointers

libavcodec/cbs_h2645.c

@@ -28,6 +28,7 @@
 #include "h264.h"
 #include "h2645_parse.h"
 #include "hevc.h"
+#include "refstruct.h"
 #include "vvc.h"
 
 
@@ -733,12 +734,8 @@ static int cbs_h26 ## h26n ## _replace_ ## ps_var(CodedBitstreamContext *ctx, \
         return err; \
     if (priv->ps_var[id] == priv->active_ ## ps_var) \
         priv->active_ ## ps_var = NULL ; \
-    av_buffer_unref(&priv->ps_var ## _ref[id]); \
     av_assert0(unit->content_ref); \
-    priv->ps_var ## _ref[id] = av_buffer_ref(unit->content_ref); \
-    if (!priv->ps_var ## _ref[id]) \
-        return AVERROR(ENOMEM); \
-    priv->ps_var[id] = (H26 ## h26n ## Raw ## ps_name *)priv->ps_var ## _ref[id]->data; \
+    ff_refstruct_replace(&priv->ps_var[id], unit->content_ref); \
     return 0; \
 }
 
@@ -758,12 +755,8 @@ static int cbs_h26 ## h26n ## _replace_ ## ps_var(CodedBitstreamContext *ctx, \
     int err = ff_cbs_make_unit_refcounted(ctx, unit); \
     if (err < 0) \
         return err; \
-    av_buffer_unref(&priv->ps_var ## _ref[id]); \
     av_assert0(unit->content_ref); \
-    priv->ps_var ## _ref[id] = av_buffer_ref(unit->content_ref); \
-    if (!priv->ps_var ## _ref[id]) \
-        return AVERROR(ENOMEM); \
-    priv->ps_var[id] = (H26 ## h26n ## Raw ## ps_name *)priv->ps_var ## _ref[id]->data; \
+    ff_refstruct_replace(&priv->ps_var[id], unit->content_ref); \
     return 0; \
 }
 
@@ -782,9 +775,7 @@ static int cbs_h266_replace_ph(CodedBitstreamContext *ctx,
     if (err < 0)
         return err;
     av_assert0(unit->content_ref);
-    err = av_buffer_replace(&h266->ph_ref, unit->content_ref);
-    if (err < 0)
-        return err;
+    ff_refstruct_replace(&h266->ph_ref, unit->content_ref);
     h266->ph = ph;
     return 0;
 }
@@ -1848,14 +1839,10 @@ static void cbs_h264_flush(CodedBitstreamContext *ctx)
 {
     CodedBitstreamH264Context *h264 = ctx->priv_data;
 
-    for (int i = 0; i < FF_ARRAY_ELEMS(h264->sps); i++) {
-        av_buffer_unref(&h264->sps_ref[i]);
-        h264->sps[i] = NULL;
-    }
-    for (int i = 0; i < FF_ARRAY_ELEMS(h264->pps); i++) {
-        av_buffer_unref(&h264->pps_ref[i]);
-        h264->pps[i] = NULL;
-    }
+    for (int i = 0; i < FF_ARRAY_ELEMS(h264->sps); i++)
+        ff_refstruct_unref(&h264->sps[i]);
+    for (int i = 0; i < FF_ARRAY_ELEMS(h264->pps); i++)
+        ff_refstruct_unref(&h264->pps[i]);
 
     h264->active_sps = NULL;
     h264->active_pps = NULL;
@@ -1870,27 +1857,21 @@ static void cbs_h264_close(CodedBitstreamContext *ctx)
     ff_h2645_packet_uninit(&h264->common.read_packet);
 
     for (i = 0; i < FF_ARRAY_ELEMS(h264->sps); i++)
-        av_buffer_unref(&h264->sps_ref[i]);
+        ff_refstruct_unref(&h264->sps[i]);
     for (i = 0; i < FF_ARRAY_ELEMS(h264->pps); i++)
-        av_buffer_unref(&h264->pps_ref[i]);
+        ff_refstruct_unref(&h264->pps[i]);
 }
 
 static void cbs_h265_flush(CodedBitstreamContext *ctx)
 {
     CodedBitstreamH265Context *h265 = ctx->priv_data;
 
-    for (int i = 0; i < FF_ARRAY_ELEMS(h265->vps); i++) {
-        av_buffer_unref(&h265->vps_ref[i]);
-        h265->vps[i] = NULL;
-    }
-    for (int i = 0; i < FF_ARRAY_ELEMS(h265->sps); i++) {
-        av_buffer_unref(&h265->sps_ref[i]);
-        h265->sps[i] = NULL;
-    }
-    for (int i = 0; i < FF_ARRAY_ELEMS(h265->pps); i++) {
-        av_buffer_unref(&h265->pps_ref[i]);
-        h265->pps[i] = NULL;
-    }
+    for (int i = 0; i < FF_ARRAY_ELEMS(h265->vps); i++)
+        ff_refstruct_unref(&h265->vps[i]);
+    for (int i = 0; i < FF_ARRAY_ELEMS(h265->sps); i++)
+        ff_refstruct_unref(&h265->sps[i]);
+    for (int i = 0; i < FF_ARRAY_ELEMS(h265->pps); i++)
+        ff_refstruct_unref(&h265->pps[i]);
 
     h265->active_vps = NULL;
     h265->active_sps = NULL;
@@ -1905,32 +1886,24 @@ static void cbs_h265_close(CodedBitstreamContext *ctx)
     ff_h2645_packet_uninit(&h265->common.read_packet);
 
     for (i = 0; i < FF_ARRAY_ELEMS(h265->vps); i++)
-        av_buffer_unref(&h265->vps_ref[i]);
+        ff_refstruct_unref(&h265->vps[i]);
     for (i = 0; i < FF_ARRAY_ELEMS(h265->sps); i++)
-        av_buffer_unref(&h265->sps_ref[i]);
+        ff_refstruct_unref(&h265->sps[i]);
     for (i = 0; i < FF_ARRAY_ELEMS(h265->pps); i++)
-        av_buffer_unref(&h265->pps_ref[i]);
+        ff_refstruct_unref(&h265->pps[i]);
 }
 
 static void cbs_h266_flush(CodedBitstreamContext *ctx)
 {
     CodedBitstreamH266Context *h266 = ctx->priv_data;
 
-    for (int i = 0; i < FF_ARRAY_ELEMS(h266->vps); i++) {
-        av_buffer_unref(&h266->vps_ref[i]);
-        h266->vps[i] = NULL;
-    }
-
-    for (int i = 0; i < FF_ARRAY_ELEMS(h266->sps); i++) {
-        av_buffer_unref(&h266->sps_ref[i]);
-        h266->sps[i] = NULL;
-    }
-    for (int i = 0; i < FF_ARRAY_ELEMS(h266->pps); i++) {
-        av_buffer_unref(&h266->pps_ref[i]);
-        h266->pps[i] = NULL;
-    }
-    av_buffer_unref(&h266->ph_ref);
-    h266->ph = NULL;
+    for (int i = 0; i < FF_ARRAY_ELEMS(h266->vps); i++)
+        ff_refstruct_unref(&h266->vps[i]);
+    for (int i = 0; i < FF_ARRAY_ELEMS(h266->sps); i++)
+        ff_refstruct_unref(&h266->sps[i]);
+    for (int i = 0; i < FF_ARRAY_ELEMS(h266->pps); i++)
+        ff_refstruct_unref(&h266->pps[i]);
+    ff_refstruct_unref(&h266->ph_ref);
 }
 
 static void cbs_h266_close(CodedBitstreamContext *ctx)
@@ -1941,11 +1914,10 @@ static void cbs_h266_close(CodedBitstreamContext *ctx)
     ff_h2645_packet_uninit(&h266->common.read_packet);
  }
 
-static void cbs_h264_free_sei(void *opaque, uint8_t *content)
+static void cbs_h264_free_sei(FFRefStructOpaque unused, void *content)
 {
-    H264RawSEI *sei = (H264RawSEI*)content;
+    H264RawSEI *sei = content;
     ff_cbs_sei_free_message_list(&sei->message_list);
-    av_free(content);
 }
 
 static const CodedBitstreamUnitTypeDescriptor cbs_h264_unit_types[] = {
@@ -1968,11 +1940,10 @@ static const CodedBitstreamUnitTypeDescriptor cbs_h264_unit_types[] = {
     CBS_UNIT_TYPE_END_OF_LIST
 };
 
-static void cbs_h265_free_sei(void *opaque, uint8_t *content)
+static void cbs_h265_free_sei(FFRefStructOpaque unused, void *content)
 {
-    H265RawSEI *sei = (H265RawSEI*)content;
+    H265RawSEI *sei = content;
     ff_cbs_sei_free_message_list(&sei->message_list);
-    av_free(content);
 }
 
 static const CodedBitstreamUnitTypeDescriptor cbs_h265_unit_types[] = {
@@ -1995,11 +1966,10 @@ static const CodedBitstreamUnitTypeDescriptor cbs_h265_unit_types[] = {
     CBS_UNIT_TYPE_END_OF_LIST
 };
 
-static void cbs_h266_free_sei(void *opaque, uint8_t *content)
+static void cbs_h266_free_sei(FFRefStructOpaque unused, void *content)
 {
-    H266RawSEI *sei = (H266RawSEI*)content;
+    H266RawSEI *sei = content;
     ff_cbs_sei_free_message_list(&sei->message_list);
-    av_free(content);
 }
 
 static const CodedBitstreamUnitTypeDescriptor cbs_h266_unit_types[] = {

libavcodec/cbs_h265.h

@@ -681,12 +681,9 @@ typedef struct CodedBitstreamH265Context {
 
     // All currently available parameter sets.  These are updated when
     // any parameter set NAL unit is read/written with this context.
-    AVBufferRef *vps_ref[HEVC_MAX_VPS_COUNT];
-    AVBufferRef *sps_ref[HEVC_MAX_SPS_COUNT];
-    AVBufferRef *pps_ref[HEVC_MAX_PPS_COUNT];
-    H265RawVPS *vps[HEVC_MAX_VPS_COUNT];
-    H265RawSPS *sps[HEVC_MAX_SPS_COUNT];
-    H265RawPPS *pps[HEVC_MAX_PPS_COUNT];
+    H265RawVPS *vps[HEVC_MAX_VPS_COUNT]; ///< RefStruct references
+    H265RawSPS *sps[HEVC_MAX_SPS_COUNT]; ///< RefStruct references
+    H265RawPPS *pps[HEVC_MAX_PPS_COUNT]; ///< RefStruct references
 
     // The currently active parameter sets.  These are updated when any
     // NAL unit refers to the relevant parameter set.  These pointers

libavcodec/cbs_h266.h

@@ -867,14 +867,11 @@ typedef struct CodedBitstreamH266Context {
 
     // All currently available parameter sets.  These are updated when
     // any parameter set NAL unit is read/written with this context.
-    AVBufferRef *vps_ref[VVC_MAX_VPS_COUNT];
-    AVBufferRef *sps_ref[VVC_MAX_SPS_COUNT];
-    AVBufferRef *pps_ref[VVC_MAX_PPS_COUNT];
-    AVBufferRef *ph_ref;
-    H266RawVPS  *vps[VVC_MAX_VPS_COUNT];
-    H266RawSPS  *sps[VVC_MAX_SPS_COUNT];
-    H266RawPPS  *pps[VVC_MAX_PPS_COUNT];
+    H266RawVPS  *vps[VVC_MAX_VPS_COUNT]; ///< RefStruct references
+    H266RawSPS  *sps[VVC_MAX_SPS_COUNT]; ///< RefStruct references
+    H266RawPPS  *pps[VVC_MAX_PPS_COUNT]; ///< RefStruct references
     H266RawPictureHeader *ph;
+    void *ph_ref; ///< RefStruct reference backing ph above
 } CodedBitstreamH266Context;
 
 #endif /* AVCODEC_CBS_H266_H */

libavcodec/cbs_h266_syntax_template.c

@@ -1074,17 +1074,13 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
 
     ub(4, sps_seq_parameter_set_id);
     ub(4, sps_video_parameter_set_id);
-    if (current->sps_video_parameter_set_id == 0 && !h266->vps_ref[0]) {
-        H266RawVPS *vps;
-        AVBufferRef *ref = av_buffer_allocz(sizeof(H266RawVPS));
-        if (!ref) {
+    if (current->sps_video_parameter_set_id == 0 && !h266->vps[0]) {
+        H266RawVPS *vps = ff_refstruct_allocz(sizeof(*vps));
+        if (!vps)
             return AVERROR(ENOMEM);
-        }
-        vps = (H266RawVPS *) ref->data;
         vps->vps_max_layers_minus1 = 0;
         vps->vps_independent_layer_flag[0] = 1;
         vps->vps_layer_id[0] = current->nal_unit_header.nuh_layer_id;
-        h266->vps_ref[0] = ref;
         h266->vps[0] = vps;
     }
 

libavcodec/cbs_internal.h

@@ -19,15 +19,16 @@
 #ifndef AVCODEC_CBS_INTERNAL_H
 #define AVCODEC_CBS_INTERNAL_H
 
+#include <stddef.h>
 #include <stdint.h>
 
-#include "libavutil/buffer.h"
 #include "libavutil/log.h"
 
 #include "cbs.h"
 #include "codec_id.h"
 #include "get_bits.h"
 #include "put_bits.h"
+#include "refstruct.h"
 
 
 enum CBSContentType {
@@ -92,8 +93,8 @@ typedef const struct CodedBitstreamUnitTypeDescriptor {
         } ref;
 
         struct {
-            void (*content_free)(void *opaque, uint8_t *data);
-            int  (*content_clone)(AVBufferRef **ref, CodedBitstreamUnit *unit);
+            void (*content_free)(FFRefStructOpaque opaque, void *content);
+            int  (*content_clone)(void **new_content, CodedBitstreamUnit *unit);
         } complex;
     } type;
 } CodedBitstreamUnitTypeDescriptor;