+#include "avio_internal.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/avstring.h"
+#include "libavutil/time.h"
+#include "url.h"
+
+#define SDP_MAX_SIZE 16384
+
+static const AVClass rtsp_muxer_class = {
+ .class_name = "RTSP muxer",
+ .item_name = av_default_item_name,
+ .option = ff_rtsp_options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+int ff_rtsp_setup_output_streams(AVFormatContext *s, const char *addr)
+{
+ RTSPState *rt = s->priv_data;
+ RTSPMessageHeader reply1, *reply = &reply1;
+ int i;
+ char *sdp;
+ AVFormatContext sdp_ctx, *ctx_array[1];
+
+ s->start_time_realtime = av_gettime();
+
+ /* Announce the stream */
+ sdp = av_mallocz(SDP_MAX_SIZE);
+ if (!sdp)
+ return AVERROR(ENOMEM);
+ /* We create the SDP based on the RTSP AVFormatContext where we
+ * aren't allowed to change the filename field. (We create the SDP
+ * based on the RTSP context since the contexts for the RTP streams
+ * don't exist yet.) In order to specify a custom URL with the actual
+ * peer IP instead of the originally specified hostname, we create
+ * a temporary copy of the AVFormatContext, where the custom URL is set.
+ *
+ * FIXME: Create the SDP without copying the AVFormatContext.
+ * This either requires setting up the RTP stream AVFormatContexts
+ * already here (complicating things immensely) or getting a more
+ * flexible SDP creation interface.
+ */
+ sdp_ctx = *s;
+ ff_url_join(sdp_ctx.filename, sizeof(sdp_ctx.filename),
+ "rtsp", NULL, addr, -1, NULL);
+ ctx_array[0] = &sdp_ctx;
+ if (av_sdp_create(ctx_array, 1, sdp, SDP_MAX_SIZE)) {
+ av_free(sdp);
+ return AVERROR_INVALIDDATA;
+ }
+ av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", sdp);
+ ff_rtsp_send_cmd_with_content(s, "ANNOUNCE", rt->control_uri,
+ "Content-Type: application/sdp\r\n",
+ reply, NULL, sdp, strlen(sdp));
+ av_free(sdp);
+ if (reply->status_code != RTSP_STATUS_OK)
+ return AVERROR_INVALIDDATA;
+
+ /* Set up the RTSPStreams for each AVStream */
+ for (i = 0; i < s->nb_streams; i++) {
+ RTSPStream *rtsp_st;
+
+ rtsp_st = av_mallocz(sizeof(RTSPStream));
+ if (!rtsp_st)
+ return AVERROR(ENOMEM);
+ dynarray_add(&rt->rtsp_streams, &rt->nb_rtsp_streams, rtsp_st);
+
+ rtsp_st->stream_index = i;
+
+ av_strlcpy(rtsp_st->control_url, rt->control_uri, sizeof(rtsp_st->control_url));
+ /* Note, this must match the relative uri set in the sdp content */
+ av_strlcatf(rtsp_st->control_url, sizeof(rtsp_st->control_url),
+ "/streamid=%d", i);
+ }
+
+ return 0;
+}