lavf: requeue attached pictures after seeking.

This allows the caller to get them without special code even after
seeking before receiving any data.

libavformat/utils.c

@@ -515,10 +515,21 @@ static AVPacket *add_to_pktbuf(AVPacketList **packet_buffer, AVPacket *pkt,
     return &pktl->pkt;
 }
 
+static void queue_attached_pictures(AVFormatContext *s)
+{
+    int i;
+    for (i = 0; i < s->nb_streams; i++)
+        if (s->streams[i]->disposition & AV_DISPOSITION_ATTACHED_PIC) {
+            AVPacket copy = s->streams[i]->attached_pic;
+            copy.destruct = NULL;
+            add_to_pktbuf(&s->raw_packet_buffer, &copy, &s->raw_packet_buffer_end);
+        }
+}
+
 int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options)
 {
     AVFormatContext *s = *ps;
-    int i, ret = 0;
+    int ret = 0;
     AVDictionary *tmp = NULL;
     ID3v2ExtraMeta *id3v2_extra_meta = NULL;
 
@@ -574,13 +585,7 @@ int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputForma
         goto fail;
     ff_id3v2_free_extra_meta(&id3v2_extra_meta);
 
-    /* queue attached pictures */
+    queue_attached_pictures(s);
-    for (i = 0; i < s->nb_streams; i++)
-        if (s->streams[i]->disposition & AV_DISPOSITION_ATTACHED_PIC) {
-            AVPacket copy = s->streams[i]->attached_pic;
-            copy.destruct = NULL;
-            add_to_pktbuf(&s->raw_packet_buffer, &copy, &s->raw_packet_buffer_end);
-        }
 
     if (s->pb && !s->data_offset)
         s->data_offset = avio_tell(s->pb);
@@ -1711,7 +1716,8 @@ static int seek_frame_generic(AVFormatContext *s,
     return 0;
 }
 
-int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
+static int seek_frame_internal(AVFormatContext *s, int stream_index,
+                               int64_t timestamp, int flags)
 {
     int ret;
     AVStream *st;
@@ -1754,14 +1760,29 @@ int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int f
         return -1;
 }
 
+int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
+{
+    int ret = seek_frame_internal(s, stream_index, timestamp, flags);
+
+    if (ret >= 0)
+        queue_attached_pictures(s);
+
+    return ret;
+}
+
 int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
 {
     if(min_ts > ts || max_ts < ts)
         return -1;
 
     if (s->iformat->read_seek2) {
+        int ret;
         ff_read_frame_flush(s);
-        return s->iformat->read_seek2(s, stream_index, min_ts, ts, max_ts, flags);
+        ret = s->iformat->read_seek2(s, stream_index, min_ts, ts, max_ts, flags);
+
+        if (ret >= 0)
+            queue_attached_pictures(s);
+        return ret;
     }
 
     if(s->iformat->read_timestamp){