rtpdec: Split mpegts parsing to a normal depacketizer

This gets rid of a number of special cases from the common rtpdec
code.

Signed-off-by: Martin Storsjö <martin@martin.st>

1 files changed, 106 insertions, 0 deletions

diff --git a/libavformat/rtpdec_mpegts.c b/libavformat/rtpdec_mpegts.c
new file mode 100644
index 0000000000..e2c8977f7d
--- /dev/null
+++ b/libavformat/rtpdec_mpegts.c
@@ -0,0 +1,106 @@
+/*
+ * RTP MPEG2TS depacketizer
+ * Copyright (c) 2003 Fabrice Bellard
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "mpegts.h"
+#include "rtpdec_formats.h"
+
+struct PayloadContext {
+    struct MpegTSContext *ts;
+    int read_buf_index;
+    int read_buf_size;
+    uint8_t buf[RTP_MAX_PACKET_LENGTH];
+};
+
+static PayloadContext *mpegts_new_context(void)
+{
+    return av_mallocz(sizeof(PayloadContext));
+}
+
+static void mpegts_free_context(PayloadContext *data)
+{
+    if (!data)
+        return;
+    if (data->ts)
+        ff_mpegts_parse_close(data->ts);
+    av_free(data);
+}
+
+static int mpegts_init(AVFormatContext *ctx, int st_index, PayloadContext *data)
+{
+    data->ts = ff_mpegts_parse_open(ctx);
+    if (!data->ts)
+        return AVERROR(ENOMEM);
+    return 0;
+}
+
+static int mpegts_handle_packet(AVFormatContext *ctx, PayloadContext *data,
+                                AVStream *st, AVPacket *pkt, uint32_t *timestamp,
+                                const uint8_t *buf, int len, uint16_t seq,
+                                int flags)
+{
+    int ret;
+
+    // We don't want to use the RTP timestamps at all. If the mpegts demuxer
+    // doesn't set any pts/dts, the generic rtpdec code shouldn't try to
+    // fill it in either, since the mpegts and RTP timestamps are in totally
+    // different ranges.
+    *timestamp = RTP_NOTS_VALUE;
+
+    if (!data->ts)
+        return AVERROR(EINVAL);
+
+    if (!buf) {
+        if (data->read_buf_index >= data->read_buf_size)
+            return AVERROR(EAGAIN);
+        ret = ff_mpegts_parse_packet(data->ts, pkt, data->buf + data->read_buf_index,
+                                     data->read_buf_size - data->read_buf_index);
+        if (ret < 0)
+            return AVERROR(EAGAIN);
+        data->read_buf_index += ret;
+        if (data->read_buf_index < data->read_buf_size)
+            return 1;
+        else
+            return 0;
+    }
+
+    ret = ff_mpegts_parse_packet(data->ts, pkt, buf, len);
+    /* The only error that can be returned from ff_mpegts_parse_packet
+     * is "no more data to return from the provided buffer", so return
+     * AVERROR(EAGAIN) for all errors */
+    if (ret < 0)
+        return AVERROR(EAGAIN);
+    if (ret < len) {
+        data->read_buf_size = FFMIN(len - ret, sizeof(data->buf));
+        memcpy(data->buf, buf + ret, data->read_buf_size);
+        data->read_buf_index = 0;
+        return 1;
+    }
+    return 0;
+}
+
+RTPDynamicProtocolHandler ff_mpegts_dynamic_handler = {
+    .codec_type        = AVMEDIA_TYPE_DATA,
+    .parse_packet      = mpegts_handle_packet,
+    .alloc             = mpegts_new_context,
+    .init              = mpegts_init,
+    .free              = mpegts_free_context,
+    .static_payload_id = 33,
+};