Libav 0.7.1
libavformat/rtspdec.c
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00001 /*
00002  * RTSP demuxer
00003  * Copyright (c) 2002 Fabrice Bellard
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/avstring.h"
00023 #include "libavutil/intreadwrite.h"
00024 #include "libavutil/opt.h"
00025 #include "avformat.h"
00026 
00027 #include "internal.h"
00028 #include "network.h"
00029 #include "os_support.h"
00030 #include "rtsp.h"
00031 #include "rdt.h"
00032 #include "url.h"
00033 
00034 static int rtsp_read_play(AVFormatContext *s)
00035 {
00036     RTSPState *rt = s->priv_data;
00037     RTSPMessageHeader reply1, *reply = &reply1;
00038     int i;
00039     char cmd[1024];
00040 
00041     av_log(s, AV_LOG_DEBUG, "hello state=%d\n", rt->state);
00042     rt->nb_byes = 0;
00043 
00044     if (!(rt->server_type == RTSP_SERVER_REAL && rt->need_subscription)) {
00045         if (rt->transport == RTSP_TRANSPORT_RTP) {
00046             for (i = 0; i < rt->nb_rtsp_streams; i++) {
00047                 RTSPStream *rtsp_st = rt->rtsp_streams[i];
00048                 RTPDemuxContext *rtpctx = rtsp_st->transport_priv;
00049                 if (!rtpctx)
00050                     continue;
00051                 ff_rtp_reset_packet_queue(rtpctx);
00052                 rtpctx->last_rtcp_ntp_time  = AV_NOPTS_VALUE;
00053                 rtpctx->first_rtcp_ntp_time = AV_NOPTS_VALUE;
00054                 rtpctx->base_timestamp      = 0;
00055                 rtpctx->rtcp_ts_offset      = 0;
00056             }
00057         }
00058         if (rt->state == RTSP_STATE_PAUSED) {
00059             cmd[0] = 0;
00060         } else {
00061             snprintf(cmd, sizeof(cmd),
00062                      "Range: npt=%"PRId64".%03"PRId64"-\r\n",
00063                      rt->seek_timestamp / AV_TIME_BASE,
00064                      rt->seek_timestamp / (AV_TIME_BASE / 1000) % 1000);
00065         }
00066         ff_rtsp_send_cmd(s, "PLAY", rt->control_uri, cmd, reply, NULL);
00067         if (reply->status_code != RTSP_STATUS_OK) {
00068             return -1;
00069         }
00070         if (rt->transport == RTSP_TRANSPORT_RTP &&
00071             reply->range_start != AV_NOPTS_VALUE) {
00072             for (i = 0; i < rt->nb_rtsp_streams; i++) {
00073                 RTSPStream *rtsp_st = rt->rtsp_streams[i];
00074                 RTPDemuxContext *rtpctx = rtsp_st->transport_priv;
00075                 AVStream *st = NULL;
00076                 if (!rtpctx || rtsp_st->stream_index < 0)
00077                     continue;
00078                 st = s->streams[rtsp_st->stream_index];
00079                 rtpctx->range_start_offset =
00080                     av_rescale_q(reply->range_start, AV_TIME_BASE_Q,
00081                                  st->time_base);
00082             }
00083         }
00084     }
00085     rt->state = RTSP_STATE_STREAMING;
00086     return 0;
00087 }
00088 
00089 /* pause the stream */
00090 static int rtsp_read_pause(AVFormatContext *s)
00091 {
00092     RTSPState *rt = s->priv_data;
00093     RTSPMessageHeader reply1, *reply = &reply1;
00094 
00095     if (rt->state != RTSP_STATE_STREAMING)
00096         return 0;
00097     else if (!(rt->server_type == RTSP_SERVER_REAL && rt->need_subscription)) {
00098         ff_rtsp_send_cmd(s, "PAUSE", rt->control_uri, NULL, reply, NULL);
00099         if (reply->status_code != RTSP_STATUS_OK) {
00100             return -1;
00101         }
00102     }
00103     rt->state = RTSP_STATE_PAUSED;
00104     return 0;
00105 }
00106 
00107 int ff_rtsp_setup_input_streams(AVFormatContext *s, RTSPMessageHeader *reply)
00108 {
00109     RTSPState *rt = s->priv_data;
00110     char cmd[1024];
00111     unsigned char *content = NULL;
00112     int ret;
00113 
00114     /* describe the stream */
00115     snprintf(cmd, sizeof(cmd),
00116              "Accept: application/sdp\r\n");
00117     if (rt->server_type == RTSP_SERVER_REAL) {
00122         av_strlcat(cmd,
00123                    "Require: com.real.retain-entity-for-setup\r\n",
00124                    sizeof(cmd));
00125     }
00126     ff_rtsp_send_cmd(s, "DESCRIBE", rt->control_uri, cmd, reply, &content);
00127     if (!content)
00128         return AVERROR_INVALIDDATA;
00129     if (reply->status_code != RTSP_STATUS_OK) {
00130         av_freep(&content);
00131         return AVERROR_INVALIDDATA;
00132     }
00133 
00134     av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", content);
00135     /* now we got the SDP description, we parse it */
00136     ret = ff_sdp_parse(s, (const char *)content);
00137     av_freep(&content);
00138     if (ret < 0)
00139         return ret;
00140 
00141     return 0;
00142 }
00143 
00144 static int rtsp_probe(AVProbeData *p)
00145 {
00146     if (av_strstart(p->filename, "rtsp:", NULL))
00147         return AVPROBE_SCORE_MAX;
00148     return 0;
00149 }
00150 
00151 static int rtsp_read_header(AVFormatContext *s,
00152                             AVFormatParameters *ap)
00153 {
00154     RTSPState *rt = s->priv_data;
00155     int ret;
00156 
00157     ret = ff_rtsp_connect(s);
00158     if (ret)
00159         return ret;
00160 
00161     rt->real_setup_cache = av_mallocz(2 * s->nb_streams * sizeof(*rt->real_setup_cache));
00162     if (!rt->real_setup_cache)
00163         return AVERROR(ENOMEM);
00164     rt->real_setup = rt->real_setup_cache + s->nb_streams;
00165 
00166 #if FF_API_FORMAT_PARAMETERS
00167     if (ap->initial_pause)
00168         rt->initial_pause = ap->initial_pause;
00169 #endif
00170 
00171     if (rt->initial_pause) {
00172          /* do not start immediately */
00173     } else {
00174          if (rtsp_read_play(s) < 0) {
00175             ff_rtsp_close_streams(s);
00176             ff_rtsp_close_connections(s);
00177             return AVERROR_INVALIDDATA;
00178         }
00179     }
00180 
00181     return 0;
00182 }
00183 
00184 int ff_rtsp_tcp_read_packet(AVFormatContext *s, RTSPStream **prtsp_st,
00185                             uint8_t *buf, int buf_size)
00186 {
00187     RTSPState *rt = s->priv_data;
00188     int id, len, i, ret;
00189     RTSPStream *rtsp_st;
00190 
00191     av_dlog(s, "tcp_read_packet:\n");
00192 redo:
00193     for (;;) {
00194         RTSPMessageHeader reply;
00195 
00196         ret = ff_rtsp_read_reply(s, &reply, NULL, 1, NULL);
00197         if (ret < 0)
00198             return ret;
00199         if (ret == 1) /* received '$' */
00200             break;
00201         /* XXX: parse message */
00202         if (rt->state != RTSP_STATE_STREAMING)
00203             return 0;
00204     }
00205     ret = ffurl_read_complete(rt->rtsp_hd, buf, 3);
00206     if (ret != 3)
00207         return -1;
00208     id  = buf[0];
00209     len = AV_RB16(buf + 1);
00210     av_dlog(s, "id=%d len=%d\n", id, len);
00211     if (len > buf_size || len < 12)
00212         goto redo;
00213     /* get the data */
00214     ret = ffurl_read_complete(rt->rtsp_hd, buf, len);
00215     if (ret != len)
00216         return -1;
00217     if (rt->transport == RTSP_TRANSPORT_RDT &&
00218         ff_rdt_parse_header(buf, len, &id, NULL, NULL, NULL, NULL) < 0)
00219         return -1;
00220 
00221     /* find the matching stream */
00222     for (i = 0; i < rt->nb_rtsp_streams; i++) {
00223         rtsp_st = rt->rtsp_streams[i];
00224         if (id >= rtsp_st->interleaved_min &&
00225             id <= rtsp_st->interleaved_max)
00226             goto found;
00227     }
00228     goto redo;
00229 found:
00230     *prtsp_st = rtsp_st;
00231     return len;
00232 }
00233 
00234 static int resetup_tcp(AVFormatContext *s)
00235 {
00236     RTSPState *rt = s->priv_data;
00237     char host[1024];
00238     int port;
00239 
00240     av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &port, NULL, 0,
00241                  s->filename);
00242     ff_rtsp_undo_setup(s);
00243     return ff_rtsp_make_setup_request(s, host, port, RTSP_LOWER_TRANSPORT_TCP,
00244                                       rt->real_challenge);
00245 }
00246 
00247 static int rtsp_read_packet(AVFormatContext *s, AVPacket *pkt)
00248 {
00249     RTSPState *rt = s->priv_data;
00250     int ret;
00251     RTSPMessageHeader reply1, *reply = &reply1;
00252     char cmd[1024];
00253 
00254 retry:
00255     if (rt->server_type == RTSP_SERVER_REAL) {
00256         int i;
00257 
00258         for (i = 0; i < s->nb_streams; i++)
00259             rt->real_setup[i] = s->streams[i]->discard;
00260 
00261         if (!rt->need_subscription) {
00262             if (memcmp (rt->real_setup, rt->real_setup_cache,
00263                         sizeof(enum AVDiscard) * s->nb_streams)) {
00264                 snprintf(cmd, sizeof(cmd),
00265                          "Unsubscribe: %s\r\n",
00266                          rt->last_subscription);
00267                 ff_rtsp_send_cmd(s, "SET_PARAMETER", rt->control_uri,
00268                                  cmd, reply, NULL);
00269                 if (reply->status_code != RTSP_STATUS_OK)
00270                     return AVERROR_INVALIDDATA;
00271                 rt->need_subscription = 1;
00272             }
00273         }
00274 
00275         if (rt->need_subscription) {
00276             int r, rule_nr, first = 1;
00277 
00278             memcpy(rt->real_setup_cache, rt->real_setup,
00279                    sizeof(enum AVDiscard) * s->nb_streams);
00280             rt->last_subscription[0] = 0;
00281 
00282             snprintf(cmd, sizeof(cmd),
00283                      "Subscribe: ");
00284             for (i = 0; i < rt->nb_rtsp_streams; i++) {
00285                 rule_nr = 0;
00286                 for (r = 0; r < s->nb_streams; r++) {
00287                     if (s->streams[r]->id == i) {
00288                         if (s->streams[r]->discard != AVDISCARD_ALL) {
00289                             if (!first)
00290                                 av_strlcat(rt->last_subscription, ",",
00291                                            sizeof(rt->last_subscription));
00292                             ff_rdt_subscribe_rule(
00293                                 rt->last_subscription,
00294                                 sizeof(rt->last_subscription), i, rule_nr);
00295                             first = 0;
00296                         }
00297                         rule_nr++;
00298                     }
00299                 }
00300             }
00301             av_strlcatf(cmd, sizeof(cmd), "%s\r\n", rt->last_subscription);
00302             ff_rtsp_send_cmd(s, "SET_PARAMETER", rt->control_uri,
00303                              cmd, reply, NULL);
00304             if (reply->status_code != RTSP_STATUS_OK)
00305                 return AVERROR_INVALIDDATA;
00306             rt->need_subscription = 0;
00307 
00308             if (rt->state == RTSP_STATE_STREAMING)
00309                 rtsp_read_play (s);
00310         }
00311     }
00312 
00313     ret = ff_rtsp_fetch_packet(s, pkt);
00314     if (ret < 0) {
00315         if (ret == AVERROR(ETIMEDOUT) && !rt->packets) {
00316             if (rt->lower_transport == RTSP_LOWER_TRANSPORT_UDP &&
00317                 rt->lower_transport_mask & (1 << RTSP_LOWER_TRANSPORT_TCP)) {
00318                 RTSPMessageHeader reply1, *reply = &reply1;
00319                 av_log(s, AV_LOG_WARNING, "UDP timeout, retrying with TCP\n");
00320                 if (rtsp_read_pause(s) != 0)
00321                     return -1;
00322                 // TEARDOWN is required on Real-RTSP, but might make
00323                 // other servers close the connection.
00324                 if (rt->server_type == RTSP_SERVER_REAL)
00325                     ff_rtsp_send_cmd(s, "TEARDOWN", rt->control_uri, NULL,
00326                                      reply, NULL);
00327                 rt->session_id[0] = '\0';
00328                 if (resetup_tcp(s) == 0) {
00329                     rt->state = RTSP_STATE_IDLE;
00330                     rt->need_subscription = 1;
00331                     if (rtsp_read_play(s) != 0)
00332                         return -1;
00333                     goto retry;
00334                 }
00335             }
00336         }
00337         return ret;
00338     }
00339     rt->packets++;
00340 
00341     /* send dummy request to keep TCP connection alive */
00342     if ((av_gettime() - rt->last_cmd_time) / 1000000 >= rt->timeout / 2) {
00343         if (rt->server_type == RTSP_SERVER_WMS ||
00344            (rt->server_type != RTSP_SERVER_REAL &&
00345             rt->get_parameter_supported)) {
00346             ff_rtsp_send_cmd_async(s, "GET_PARAMETER", rt->control_uri, NULL);
00347         } else {
00348             ff_rtsp_send_cmd_async(s, "OPTIONS", "*", NULL);
00349         }
00350     }
00351 
00352     return 0;
00353 }
00354 
00355 static int rtsp_read_seek(AVFormatContext *s, int stream_index,
00356                           int64_t timestamp, int flags)
00357 {
00358     RTSPState *rt = s->priv_data;
00359 
00360     rt->seek_timestamp = av_rescale_q(timestamp,
00361                                       s->streams[stream_index]->time_base,
00362                                       AV_TIME_BASE_Q);
00363     switch(rt->state) {
00364     default:
00365     case RTSP_STATE_IDLE:
00366         break;
00367     case RTSP_STATE_STREAMING:
00368         if (rtsp_read_pause(s) != 0)
00369             return -1;
00370         rt->state = RTSP_STATE_SEEKING;
00371         if (rtsp_read_play(s) != 0)
00372             return -1;
00373         break;
00374     case RTSP_STATE_PAUSED:
00375         rt->state = RTSP_STATE_IDLE;
00376         break;
00377     }
00378     return 0;
00379 }
00380 
00381 static int rtsp_read_close(AVFormatContext *s)
00382 {
00383     RTSPState *rt = s->priv_data;
00384 
00385 #if 0
00386     /* NOTE: it is valid to flush the buffer here */
00387     if (rt->lower_transport == RTSP_LOWER_TRANSPORT_TCP) {
00388         avio_close(&rt->rtsp_gb);
00389     }
00390 #endif
00391     ff_rtsp_send_cmd_async(s, "TEARDOWN", rt->control_uri, NULL);
00392 
00393     ff_rtsp_close_streams(s);
00394     ff_rtsp_close_connections(s);
00395     ff_network_close();
00396     rt->real_setup = NULL;
00397     av_freep(&rt->real_setup_cache);
00398     return 0;
00399 }
00400 
00401 static const AVOption options[] = {
00402     { "initial_pause",  "Don't start playing the stream immediately", offsetof(RTSPState, initial_pause),  FF_OPT_TYPE_INT, {.dbl = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM },
00403     { NULL },
00404 };
00405 
00406 const AVClass rtsp_demuxer_class = {
00407     .class_name     = "RTSP demuxer",
00408     .item_name      = av_default_item_name,
00409     .option         = options,
00410     .version        = LIBAVUTIL_VERSION_INT,
00411 };
00412 
00413 AVInputFormat ff_rtsp_demuxer = {
00414     "rtsp",
00415     NULL_IF_CONFIG_SMALL("RTSP input format"),
00416     sizeof(RTSPState),
00417     rtsp_probe,
00418     rtsp_read_header,
00419     rtsp_read_packet,
00420     rtsp_read_close,
00421     rtsp_read_seek,
00422     .flags = AVFMT_NOFILE,
00423     .read_play = rtsp_read_play,
00424     .read_pause = rtsp_read_pause,
00425     .priv_class = &rtsp_demuxer_class,
00426 };