avformat/avio: Move internal AVIOContext fields to avio_internal.h

Currently AVIOContext's private fields are all over AVIOContext.
This commit moves them into a new structure in avio_internal.h instead.
Said structure contains the public AVIOContext as its first element
in order to avoid having to allocate a separate AVIOContextInternal
which is costly for those use cases where one just wants to access
an already existing buffer via the AVIOContext-API.
For these cases ffio_init_context() can't fail and always returned zero,
which was typically not checked. Therefore it has been made to not
return anything.

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

1 files changed, 18 insertions, 17 deletions

diff --git a/libavformat/rtpdec_qt.c b/libavformat/rtpdec_qt.c
index 492a1b6715..6723cd1bb0 100644
--- a/libavformat/rtpdec_qt.c
+++ b/libavformat/rtpdec_qt.c
@@ -54,7 +54,8 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
                                uint32_t *timestamp, const uint8_t *buf,
                                int len, uint16_t seq, int flags)
 {
-    AVIOContext pb;
+    FFIOContext pb0;
+    AVIOContext *const pb = &pb0.pub;
     GetBitContext gb;
     int packing_scheme, has_payload_desc, has_packet_info, alen,
         has_marker_bit = flags & RTP_FLAG_MARKER,
@@ -82,7 +83,7 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
      * http://developer.apple.com/quicktime/icefloe/dispatch026.html
      */
     init_get_bits(&gb, buf, len << 3);
-    ffio_init_context(&pb, (uint8_t*)buf, len, 0, NULL, NULL, NULL, NULL);
+    ffio_init_context(&pb0, (uint8_t*)buf, len, 0, NULL, NULL, NULL, NULL);
 
     if (len < 4)
         return AVERROR_INVALIDDATA;
@@ -114,22 +115,22 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
         skip_bits(&gb, 12); // reserved
         data_len = get_bits(&gb, 16);
 
-        avio_seek(&pb, pos + 4, SEEK_SET);
-        tag = avio_rl32(&pb);
+        avio_seek(pb, pos + 4, SEEK_SET);
+        tag = avio_rl32(pb);
         if ((st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
                  tag != MKTAG('v','i','d','e')) ||
             (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&
                  tag != MKTAG('s','o','u','n')))
             return AVERROR_INVALIDDATA;
-        avpriv_set_pts_info(st, 32, 1, avio_rb32(&pb));
+        avpriv_set_pts_info(st, 32, 1, avio_rb32(pb));
 
         if (pos + data_len > len)
             return AVERROR_INVALIDDATA;
         /* TLVs */
-        while (avio_tell(&pb) + 4 < pos + data_len) {
-            int tlv_len = avio_rb16(&pb);
-            tag = avio_rl16(&pb);
-            if (avio_tell(&pb) + tlv_len > pos + data_len)
+        while (avio_tell(pb) + 4 < pos + data_len) {
+            int tlv_len = avio_rb16(pb);
+            tag = avio_rl16(pb);
+            if (avio_tell(pb) + tlv_len > pos + data_len)
                 return AVERROR_INVALIDDATA;
 
 #define MKTAG16(a,b) MKTAG(a,b,0,0)
@@ -151,7 +152,7 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
                 /* ff_mov_read_stsd_entries updates stream s->nb_streams-1,
                  * so set it temporarily to indicate which stream to update. */
                 s->nb_streams = st->index + 1;
-                ff_mov_read_stsd_entries(mc, &pb, 1);
+                ff_mov_read_stsd_entries(mc, pb, 1);
                 qt->bytes_per_frame = msc->bytes_per_frame;
                 av_free(msc);
                 av_free(mc);
@@ -160,22 +161,22 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
                 break;
             }
             default:
-                avio_skip(&pb, tlv_len);
+                avio_skip(pb, tlv_len);
                 break;
             }
         }
 
         /* 32-bit alignment */
-        avio_skip(&pb, ((avio_tell(&pb) + 3) & ~3) - avio_tell(&pb));
+        avio_skip(pb, ((avio_tell(pb) + 3) & ~3) - avio_tell(pb));
     } else
-        avio_seek(&pb, 4, SEEK_SET);
+        avio_seek(pb, 4, SEEK_SET);
 
     if (has_packet_info) {
         avpriv_request_sample(s, "RTP-X-QT with packet-specific info");
         return AVERROR_PATCHWELCOME;
     }
 
-    alen = len - avio_tell(&pb);
+    alen = len - avio_tell(pb);
     if (alen <= 0)
         return AVERROR_INVALIDDATA;
 
@@ -197,7 +198,7 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
             qt->pkt->size = 0;
             qt->timestamp = *timestamp;
         }
-        memcpy(qt->pkt->data + qt->pkt->size, buf + avio_tell(&pb), alen);
+        memcpy(qt->pkt->data + qt->pkt->size, buf + avio_tell(pb), alen);
         qt->pkt->size += alen;
         if (has_marker_bit) {
             int ret = av_packet_from_data(pkt, qt->pkt->data, qt->pkt->size);
@@ -220,7 +221,7 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
         qt->remaining = (alen / qt->bytes_per_frame) - 1;
         if ((ret = av_new_packet(pkt, qt->bytes_per_frame)) < 0)
             return ret;
-        memcpy(pkt->data, buf + avio_tell(&pb), qt->bytes_per_frame);
+        memcpy(pkt->data, buf + avio_tell(pb), qt->bytes_per_frame);
         pkt->flags = keyframe ? AV_PKT_FLAG_KEY : 0;
         pkt->stream_index = st->index;
         if (qt->remaining > 0) {
@@ -232,7 +233,7 @@ static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt,
             }
             qt->pkt->size = qt->remaining * qt->bytes_per_frame;
             memcpy(qt->pkt->data,
-                   buf + avio_tell(&pb) + qt->bytes_per_frame,
+                   buf + avio_tell(pb) + qt->bytes_per_frame,
                    qt->remaining * qt->bytes_per_frame);
             qt->pkt->flags = pkt->flags;
             return 1;