avformat: Add and use helper function to add attachment streams

All instances of adding attached pictures to a stream or adding
a stream and an attached packet to said stream have several things
in common like setting the index and flags of the packet, setting
the stream disposition etc. This commit therefore factors this out.

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

8 files changed, 66 insertions, 77 deletions

diff --git a/libavformat/apetag.c b/libavformat/apetag.c
index 23ee6b516d..6f82fbe202 100644
--- a/libavformat/apetag.c
+++ b/libavformat/apetag.c
@@ -79,20 +79,12 @@ static int ape_tag_read_field(AVFormatContext *s)
         av_dict_set(&st->metadata, key, filename, 0);
 
         if ((id = ff_guess_image2_codec(filename)) != AV_CODEC_ID_NONE) {
-            int ret;
-
-            ret = av_get_packet(s->pb, &st->attached_pic, size);
+            int ret = ff_add_attached_pic(s, st, s->pb, NULL, size);
             if (ret < 0) {
                 av_log(s, AV_LOG_ERROR, "Error reading cover art.\n");
                 return ret;
             }
-
-            st->disposition      |= AV_DISPOSITION_ATTACHED_PIC;
-            st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
             st->codecpar->codec_id   = id;
-
-            st->attached_pic.stream_index = st->index;
-            st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
         } else {
             if ((ret = ff_get_extradata(s, st->codecpar, s->pb, size)) < 0)
                 return ret;
diff --git a/libavformat/flac_picture.c b/libavformat/flac_picture.c
index f15cfa877a..96e14f76c9 100644
--- a/libavformat/flac_picture.c
+++ b/libavformat/flac_picture.c
@@ -160,20 +160,11 @@ int ff_flac_parse_picture(AVFormatContext *s, uint8_t *buf, int buf_size, int tr
     if (AV_RB64(data->data) == PNGSIG)
         id = AV_CODEC_ID_PNG;
 
-    st = avformat_new_stream(s, NULL);
-    if (!st) {
-        RETURN_ERROR(AVERROR(ENOMEM));
-    }
-
-    av_packet_unref(&st->attached_pic);
-    st->attached_pic.buf          = data;
-    st->attached_pic.data         = data->data;
-    st->attached_pic.size         = len;
-    st->attached_pic.stream_index = st->index;
-    st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
+    ret = ff_add_attached_pic(s, NULL, NULL, &data, 0);
+    if (ret < 0)
+        RETURN_ERROR(ret);
 
-    st->disposition      |= AV_DISPOSITION_ATTACHED_PIC;
-    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+    st = s->streams[s->nb_streams - 1];
     st->codecpar->codec_id   = id;
     st->codecpar->width      = width;
     st->codecpar->height     = height;
diff --git a/libavformat/id3v2.c b/libavformat/id3v2.c
index f33b7ba93a..863709abbf 100644
--- a/libavformat/id3v2.c
+++ b/libavformat/id3v2.c
@@ -1142,34 +1142,25 @@ int ff_id3v2_parse_apic(AVFormatContext *s, ID3v2ExtraMeta *extra_meta)
     for (cur = extra_meta; cur; cur = cur->next) {
         ID3v2ExtraMetaAPIC *apic;
         AVStream *st;
+        int ret;
 
         if (strcmp(cur->tag, "APIC"))
             continue;
         apic = &cur->data.apic;
 
-        if (!(st = avformat_new_stream(s, NULL)))
-            return AVERROR(ENOMEM);
-
-        st->disposition      |= AV_DISPOSITION_ATTACHED_PIC;
-        st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+        ret = ff_add_attached_pic(s, NULL, NULL, &apic->buf, 0);
+        if (ret < 0)
+            return ret;
+        st  = s->streams[s->nb_streams - 1];
         st->codecpar->codec_id   = apic->id;
 
-        if (AV_RB64(apic->buf->data) == PNGSIG)
+        if (AV_RB64(st->attached_pic.data) == PNGSIG)
             st->codecpar->codec_id = AV_CODEC_ID_PNG;
 
         if (apic->description[0])
             av_dict_set(&st->metadata, "title", apic->description, 0);
 
         av_dict_set(&st->metadata, "comment", apic->type, 0);
-
-        av_packet_unref(&st->attached_pic);
-        st->attached_pic.buf          = apic->buf;
-        st->attached_pic.data         = apic->buf->data;
-        st->attached_pic.size         = apic->buf->size - AV_INPUT_BUFFER_PADDING_SIZE;
-        st->attached_pic.stream_index = st->index;
-        st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
-
-        apic->buf = NULL;
     }
 
     return 0;
diff --git a/libavformat/internal.h b/libavformat/internal.h
index 8631694d00..b3c5d8a1d5 100644
--- a/libavformat/internal.h
+++ b/libavformat/internal.h
@@ -670,6 +670,19 @@ int ff_framehash_write_header(AVFormatContext *s);
 int ff_read_packet(AVFormatContext *s, AVPacket *pkt);
 
 /**
+ * Add an attached pic to an AVStream.
+ *
+ * @param st   if set, the stream to add the attached pic to;
+ *             if unset, a new stream will be added to s.
+ * @param pb   AVIOContext to read data from if buf is unset.
+ * @param buf  if set, it contains the data and size information to be used
+ *             for the attached pic; if unset, data is read from pb.
+ * @param size the size of the data to read if buf is unset.
+ */
+int ff_add_attached_pic(AVFormatContext *s, AVStream *st, AVIOContext *pb,
+                        AVBufferRef **buf, int size);
+
+/**
  * Interleave an AVPacket per dts so it can be muxed.
  *
  * @param s   an AVFormatContext for output. pkt resp. out will be added to
diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index 1dc188c946..e8c76f9cfb 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -3007,18 +3007,9 @@ static int matroska_read_header(AVFormatContext *s)
             attachments[j].stream = st;
 
             if (st->codecpar->codec_id != AV_CODEC_ID_NONE) {
-                AVPacket *pkt = &st->attached_pic;
-
-                st->disposition         |= AV_DISPOSITION_ATTACHED_PIC;
-                st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
-
-                av_packet_unref(pkt);
-                pkt->buf          = attachments[j].bin.buf;
-                attachments[j].bin.buf = NULL;
-                pkt->data         = attachments[j].bin.data;
-                pkt->size         = attachments[j].bin.size;
-                pkt->stream_index = st->index;
-                pkt->flags       |= AV_PKT_FLAG_KEY;
+                res = ff_add_attached_pic(s, st, NULL, &attachments[j].bin.buf, 0);
+                if (res < 0)
+                    goto fail;
             } else {
                 st->codecpar->codec_type = AVMEDIA_TYPE_ATTACHMENT;
                 if (ff_alloc_extradata(st->codecpar, attachments[j].bin.size))
diff --git a/libavformat/mov.c b/libavformat/mov.c
index a1411264ec..7805330bf9 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -196,17 +196,16 @@ static int mov_read_covr(MOVContext *c, AVIOContext *pb, int type, int len)
         return 0;
     }
 
-    st = avformat_new_stream(c->fc, NULL);
-    if (!st)
-        return AVERROR(ENOMEM);
     sc = av_mallocz(sizeof(*sc));
     if (!sc)
         return AVERROR(ENOMEM);
-    st->priv_data = sc;
-
-    ret = av_get_packet(pb, &st->attached_pic, len);
-    if (ret < 0)
+    ret = ff_add_attached_pic(c->fc, NULL, pb, NULL, len);
+    if (ret < 0) {
+        av_free(sc);
         return ret;
+    }
+    st = c->fc->streams[c->fc->nb_streams - 1];
+    st->priv_data = sc;
 
     if (st->attached_pic.size >= 8 && id != AV_CODEC_ID_BMP) {
         if (AV_RB64(st->attached_pic.data) == 0x89504e470d0a1a0a) {
@@ -215,13 +214,6 @@ static int mov_read_covr(MOVContext *c, AVIOContext *pb, int type, int len)
             id = AV_CODEC_ID_MJPEG;
         }
     }
-
-    st->disposition              |= AV_DISPOSITION_ATTACHED_PIC;
-
-    st->attached_pic.stream_index = st->index;
-    st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
-
-    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
     st->codecpar->codec_id   = id;
 
     return 0;
@@ -7233,11 +7225,8 @@ static void mov_read_chapters(AVFormatContext *s)
                     goto finish;
                 }
 
-                if (av_get_packet(sc->pb, &st->attached_pic, sample->size) < 0)
+                if (ff_add_attached_pic(s, st, sc->pb, NULL, sample->size) < 0)
                     goto finish;
-
-                st->attached_pic.stream_index = st->index;
-                st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
             }
         } else {
             st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 92695c3f2b..c2200d0403 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -474,6 +474,36 @@ int avformat_queue_attached_pictures(AVFormatContext *s)
     return 0;
 }
 
+int ff_add_attached_pic(AVFormatContext *s, AVStream *st, AVIOContext *pb,
+                        AVBufferRef **buf, int size)
+{
+    AVPacket *pkt;
+    int ret;
+
+    if (!st && !(st = avformat_new_stream(s, NULL)))
+        return AVERROR(ENOMEM);
+    pkt = &st->attached_pic;
+    if (buf) {
+        av_assert1(*buf);
+        av_packet_unref(pkt);
+        pkt->buf  = *buf;
+        pkt->data = (*buf)->data;
+        pkt->size = (*buf)->size - AV_INPUT_BUFFER_PADDING_SIZE;
+        *buf = NULL;
+    } else {
+        ret = av_get_packet(pb, pkt, size);
+        if (ret < 0)
+            return ret;
+    }
+    st->disposition         |= AV_DISPOSITION_ATTACHED_PIC;
+    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+
+    pkt->stream_index = st->index;
+    pkt->flags       |= AV_PKT_FLAG_KEY;
+
+    return 0;
+}
+
 static int update_stream_avctx(AVFormatContext *s)
 {
     int i, ret;
diff --git a/libavformat/wtvdec.c b/libavformat/wtvdec.c
index 4b3b7fb407..44ca86d517 100644
--- a/libavformat/wtvdec.c
+++ b/libavformat/wtvdec.c
@@ -434,7 +434,6 @@ static void get_attachment(AVFormatContext *s, AVIOContext *pb, int length)
     char description[1024];
     unsigned int filesize;
     AVStream *st;
-    int ret;
     int64_t pos = avio_tell(pb);
 
     avio_get_str16le(pb, INT_MAX, mime, sizeof(mime));
@@ -447,19 +446,12 @@ static void get_attachment(AVFormatContext *s, AVIOContext *pb, int length)
     if (!filesize)
         goto done;
 
-    st = avformat_new_stream(s, NULL);
-    if (!st)
+    if (ff_add_attached_pic(s, NULL, pb, NULL, filesize) < 0)
         goto done;
+    st = s->streams[s->nb_streams - 1];
     av_dict_set(&st->metadata, "title", description, 0);
-    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
     st->codecpar->codec_id   = AV_CODEC_ID_MJPEG;
     st->id = -1;
-    ret = av_get_packet(pb, &st->attached_pic, filesize);
-    if (ret < 0)
-        goto done;
-    st->attached_pic.stream_index = st->index;
-    st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
-    st->disposition              |= AV_DISPOSITION_ATTACHED_PIC;
 done:
     avio_seek(pb, pos + length, SEEK_SET);
 }