FFmpeg: libavformat/sapenc.c Source File

00001 /*
00002  * Session Announcement Protocol (RFC 2974) muxer
00003  * Copyright (c) 2010 Martin Storsjo
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "avformat.h"
00023 #include "libavutil/parseutils.h"
00024 #include "libavutil/random_seed.h"
00025 #include "libavutil/avstring.h"
00026 #include "libavutil/intreadwrite.h"
00027 #include "internal.h"
00028 #include "network.h"
00029 #include "os_support.h"
00030 #include "rtpenc_chain.h"
00031 #include "url.h"
00032 
00033 struct SAPState {
00034     uint8_t    *ann;
00035     int         ann_size;
00036     URLContext *ann_fd;
00037     int64_t     last_time;
00038 };
00039 
00040 static int sap_write_close(AVFormatContext *s)
00041 {
00042     struct SAPState *sap = s->priv_data;
00043     int i;
00044 
00045     for (i = 0; i < s->nb_streams; i++) {
00046         AVFormatContext *rtpctx = s->streams[i]->priv_data;
00047         if (!rtpctx)
00048             continue;
00049         av_write_trailer(rtpctx);
00050         avio_close(rtpctx->pb);
00051         avformat_free_context(rtpctx);
00052         s->streams[i]->priv_data = NULL;
00053     }
00054 
00055     if (sap->last_time && sap->ann && sap->ann_fd) {
00056         sap->ann[0] |= 4; /* Session deletion*/
00057         ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
00058     }
00059 
00060     av_freep(&sap->ann);
00061     if (sap->ann_fd)
00062         ffurl_close(sap->ann_fd);
00063     ff_network_close();
00064     return 0;
00065 }
00066 
00067 static int sap_write_header(AVFormatContext *s)
00068 {
00069     struct SAPState *sap = s->priv_data;
00070     char host[1024], path[1024], url[1024], announce_addr[50] = "";
00071     char *option_list;
00072     int port = 9875, base_port = 5004, i, pos = 0, same_port = 0, ttl = 255;
00073     AVFormatContext **contexts = NULL;
00074     int ret = 0;
00075     struct sockaddr_storage localaddr;
00076     socklen_t addrlen = sizeof(localaddr);
00077     int udp_fd;
00078 
00079     if (!ff_network_init())
00080         return AVERROR(EIO);
00081 
00082     /* extract hostname and port */
00083     av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &base_port,
00084                  path, sizeof(path), s->filename);
00085     if (base_port < 0)
00086         base_port = 5004;
00087 
00088     /* search for options */
00089     option_list = strrchr(path, '?');
00090     if (option_list) {
00091         char buf[50];
00092         if (av_find_info_tag(buf, sizeof(buf), "announce_port", option_list)) {
00093             port = strtol(buf, NULL, 10);
00094         }
00095         if (av_find_info_tag(buf, sizeof(buf), "same_port", option_list)) {
00096             same_port = strtol(buf, NULL, 10);
00097         }
00098         if (av_find_info_tag(buf, sizeof(buf), "ttl", option_list)) {
00099             ttl = strtol(buf, NULL, 10);
00100         }
00101         if (av_find_info_tag(buf, sizeof(buf), "announce_addr", option_list)) {
00102             av_strlcpy(announce_addr, buf, sizeof(announce_addr));
00103         }
00104     }
00105 
00106     if (!announce_addr[0]) {
00107         struct addrinfo hints, *ai = NULL;
00108         memset(&hints, 0, sizeof(hints));
00109         hints.ai_family = AF_UNSPEC;
00110         if (getaddrinfo(host, NULL, &hints, &ai)) {
00111             av_log(s, AV_LOG_ERROR, "Unable to resolve %s\n", host);
00112             ret = AVERROR(EIO);
00113             goto fail;
00114         }
00115         if (ai->ai_family == AF_INET) {
00116             /* Also known as sap.mcast.net */
00117             av_strlcpy(announce_addr, "224.2.127.254", sizeof(announce_addr));
00118 #if HAVE_STRUCT_SOCKADDR_IN6
00119         } else if (ai->ai_family == AF_INET6) {
00120             /* With IPv6, you can use the same destination in many different
00121              * multicast subnets, to choose how far you want it routed.
00122              * This one is intended to be routed globally. */
00123             av_strlcpy(announce_addr, "ff0e::2:7ffe", sizeof(announce_addr));
00124 #endif
00125         } else {
00126             freeaddrinfo(ai);
00127             av_log(s, AV_LOG_ERROR, "Host %s resolved to unsupported "
00128                                     "address family\n", host);
00129             ret = AVERROR(EIO);
00130             goto fail;
00131         }
00132         freeaddrinfo(ai);
00133     }
00134 
00135     contexts = av_mallocz(sizeof(AVFormatContext*) * s->nb_streams);
00136     if (!contexts) {
00137         ret = AVERROR(ENOMEM);
00138         goto fail;
00139     }
00140 
00141     s->start_time_realtime = av_gettime();
00142     for (i = 0; i < s->nb_streams; i++) {
00143         URLContext *fd;
00144 
00145         ff_url_join(url, sizeof(url), "rtp", NULL, host, base_port,
00146                     "?ttl=%d", ttl);
00147         if (!same_port)
00148             base_port += 2;
00149         ret = ffurl_open(&fd, url, AVIO_FLAG_WRITE);
00150         if (ret) {
00151             ret = AVERROR(EIO);
00152             goto fail;
00153         }
00154         s->streams[i]->priv_data = contexts[i] =
00155             ff_rtp_chain_mux_open(s, s->streams[i], fd, 0);
00156         av_strlcpy(contexts[i]->filename, url, sizeof(contexts[i]->filename));
00157     }
00158 
00159     ff_url_join(url, sizeof(url), "udp", NULL, announce_addr, port,
00160                 "?ttl=%d&connect=1", ttl);
00161     ret = ffurl_open(&sap->ann_fd, url, AVIO_FLAG_WRITE);
00162     if (ret) {
00163         ret = AVERROR(EIO);
00164         goto fail;
00165     }
00166 
00167     udp_fd = ffurl_get_file_handle(sap->ann_fd);
00168     if (getsockname(udp_fd, (struct sockaddr*) &localaddr, &addrlen)) {
00169         ret = AVERROR(EIO);
00170         goto fail;
00171     }
00172     if (localaddr.ss_family != AF_INET
00173 #if HAVE_STRUCT_SOCKADDR_IN6
00174         && localaddr.ss_family != AF_INET6
00175 #endif
00176         ) {
00177         av_log(s, AV_LOG_ERROR, "Unsupported protocol family\n");
00178         ret = AVERROR(EIO);
00179         goto fail;
00180     }
00181     sap->ann_size = 8192;
00182     sap->ann = av_mallocz(sap->ann_size);
00183     if (!sap->ann) {
00184         ret = AVERROR(EIO);
00185         goto fail;
00186     }
00187     sap->ann[pos] = (1 << 5);
00188 #if HAVE_STRUCT_SOCKADDR_IN6
00189     if (localaddr.ss_family == AF_INET6)
00190         sap->ann[pos] |= 0x10;
00191 #endif
00192     pos++;
00193     sap->ann[pos++] = 0; /* Authentication length */
00194     AV_WB16(&sap->ann[pos], av_get_random_seed());
00195     pos += 2;
00196     if (localaddr.ss_family == AF_INET) {
00197         memcpy(&sap->ann[pos], &((struct sockaddr_in*)&localaddr)->sin_addr,
00198                sizeof(struct in_addr));
00199         pos += sizeof(struct in_addr);
00200 #if HAVE_STRUCT_SOCKADDR_IN6
00201     } else {
00202         memcpy(&sap->ann[pos], &((struct sockaddr_in6*)&localaddr)->sin6_addr,
00203                sizeof(struct in6_addr));
00204         pos += sizeof(struct in6_addr);
00205 #endif
00206     }
00207 
00208     av_strlcpy(&sap->ann[pos], "application/sdp", sap->ann_size - pos);
00209     pos += strlen(&sap->ann[pos]) + 1;
00210 
00211     if (av_sdp_create(contexts, s->nb_streams, &sap->ann[pos],
00212                        sap->ann_size - pos)) {
00213         ret = AVERROR_INVALIDDATA;
00214         goto fail;
00215     }
00216     av_freep(&contexts);
00217     av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", &sap->ann[pos]);
00218     pos += strlen(&sap->ann[pos]);
00219     sap->ann_size = pos;
00220 
00221     if (sap->ann_size > sap->ann_fd->max_packet_size) {
00222         av_log(s, AV_LOG_ERROR, "Announcement too large to send in one "
00223                                 "packet\n");
00224         goto fail;
00225     }
00226 
00227     return 0;
00228 
00229 fail:
00230     av_free(contexts);
00231     sap_write_close(s);
00232     return ret;
00233 }
00234 
00235 static int sap_write_packet(AVFormatContext *s, AVPacket *pkt)
00236 {
00237     AVFormatContext *rtpctx;
00238     struct SAPState *sap = s->priv_data;
00239     int64_t now = av_gettime();
00240 
00241     if (!sap->last_time || now - sap->last_time > 5000000) {
00242         int ret = ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
00243         /* Don't abort even if we get "Destination unreachable" */
00244         if (ret < 0 && ret != AVERROR(ECONNREFUSED))
00245             return ret;
00246         sap->last_time = now;
00247     }
00248     rtpctx = s->streams[pkt->stream_index]->priv_data;
00249     return ff_write_chained(rtpctx, 0, pkt, s);
00250 }
00251 
00252 AVOutputFormat ff_sap_muxer = {
00253     "sap",
00254     NULL_IF_CONFIG_SMALL("SAP output format"),
00255     NULL,
00256     NULL,
00257     sizeof(struct SAPState),
00258     CODEC_ID_AAC,
00259     CODEC_ID_MPEG4,
00260     sap_write_header,
00261     sap_write_packet,
00262     sap_write_close,
00263     .flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER,
00264 };
00265