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/random_seed.h"
00024 #include "libavutil/avstring.h"
00025 #include "libavutil/intreadwrite.h"
00026 #include "internal.h"
00027 #include "network.h"
00028 #include "os_support.h"
00029 #include "rtpenc_chain.h"
00030 
00031 struct SAPState {
00032     uint8_t    *ann;
00033     int         ann_size;
00034     URLContext *ann_fd;
00035     int64_t     last_time;
00036 };
00037 
00038 static int sap_write_close(AVFormatContext *s)
00039 {
00040     struct SAPState *sap = s->priv_data;
00041     int i;
00042 
00043     for (i = 0; i < s->nb_streams; i++) {
00044         AVFormatContext *rtpctx = s->streams[i]->priv_data;
00045         if (!rtpctx)
00046             continue;
00047         av_write_trailer(rtpctx);
00048         url_fclose(rtpctx->pb);
00049         av_metadata_free(&rtpctx->streams[0]->metadata);
00050         av_metadata_free(&rtpctx->metadata);
00051         av_free(rtpctx->streams[0]);
00052         av_free(rtpctx);
00053         s->streams[i]->priv_data = NULL;
00054     }
00055 
00056     if (sap->last_time && sap->ann && sap->ann_fd) {
00057         sap->ann[0] |= 4; /* Session deletion*/
00058         url_write(sap->ann_fd, sap->ann, sap->ann_size);
00059     }
00060 
00061     av_freep(&sap->ann);
00062     if (sap->ann_fd)
00063         url_close(sap->ann_fd);
00064     ff_network_close();
00065     return 0;
00066 }
00067 
00068 static int sap_write_header(AVFormatContext *s)
00069 {
00070     struct SAPState *sap = s->priv_data;
00071     char host[1024], path[1024], url[1024], announce_addr[50] = "";
00072     char *option_list;
00073     int port = 9875, base_port = 5004, i, pos = 0, same_port = 0, ttl = 255;
00074     AVFormatContext **contexts = NULL;
00075     int ret = 0;
00076     struct sockaddr_storage localaddr;
00077     socklen_t addrlen = sizeof(localaddr);
00078     int udp_fd;
00079 
00080     if (!ff_network_init())
00081         return AVERROR(EIO);
00082 
00083     /* extract hostname and port */
00084     av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &base_port,
00085                  path, sizeof(path), s->filename);
00086     if (base_port < 0)
00087         base_port = 5004;
00088 
00089     /* search for options */
00090     option_list = strrchr(path, '?');
00091     if (option_list) {
00092         char buf[50];
00093         if (find_info_tag(buf, sizeof(buf), "announce_port", option_list)) {
00094             port = strtol(buf, NULL, 10);
00095         }
00096         if (find_info_tag(buf, sizeof(buf), "same_port", option_list)) {
00097             same_port = strtol(buf, NULL, 10);
00098         }
00099         if (find_info_tag(buf, sizeof(buf), "ttl", option_list)) {
00100             ttl = strtol(buf, NULL, 10);
00101         }
00102         if (find_info_tag(buf, sizeof(buf), "announce_addr", option_list)) {
00103             av_strlcpy(announce_addr, buf, sizeof(announce_addr));
00104         }
00105     }
00106 
00107     if (!announce_addr[0]) {
00108         struct addrinfo hints, *ai = NULL;
00109         memset(&hints, 0, sizeof(hints));
00110         hints.ai_family = AF_UNSPEC;
00111         if (getaddrinfo(host, NULL, &hints, &ai)) {
00112             av_log(s, AV_LOG_ERROR, "Unable to resolve %s\n", host);
00113             ret = AVERROR(EIO);
00114             goto fail;
00115         }
00116         if (ai->ai_family == AF_INET) {
00117             /* Also known as sap.mcast.net */
00118             av_strlcpy(announce_addr, "224.2.127.254", sizeof(announce_addr));
00119 #if HAVE_STRUCT_SOCKADDR_IN6
00120         } else if (ai->ai_family == AF_INET6) {
00121             /* With IPv6, you can use the same destination in many different
00122              * multicast subnets, to choose how far you want it routed.
00123              * This one is intended to be routed globally. */
00124             av_strlcpy(announce_addr, "ff0e::2:7ffe", sizeof(announce_addr));
00125 #endif
00126         } else {
00127             freeaddrinfo(ai);
00128             av_log(s, AV_LOG_ERROR, "Host %s resolved to unsupported "
00129                                     "address family\n", host);
00130             ret = AVERROR(EIO);
00131             goto fail;
00132         }
00133         freeaddrinfo(ai);
00134     }
00135 
00136     contexts = av_mallocz(sizeof(AVFormatContext*) * s->nb_streams);
00137     if (!contexts) {
00138         ret = AVERROR(ENOMEM);
00139         goto fail;
00140     }
00141 
00142     s->start_time_realtime = av_gettime();
00143     for (i = 0; i < s->nb_streams; i++) {
00144         URLContext *fd;
00145 
00146         ff_url_join(url, sizeof(url), "rtp", NULL, host, base_port,
00147                     "?ttl=%d", ttl);
00148         if (!same_port)
00149             base_port += 2;
00150         ret = url_open(&fd, url, URL_WRONLY);
00151         if (ret) {
00152             ret = AVERROR(EIO);
00153             goto fail;
00154         }
00155         s->streams[i]->priv_data = contexts[i] =
00156             ff_rtp_chain_mux_open(s, s->streams[i], fd, 0);
00157         av_strlcpy(contexts[i]->filename, url, sizeof(contexts[i]->filename));
00158     }
00159 
00160     ff_url_join(url, sizeof(url), "udp", NULL, announce_addr, port,
00161                 "?ttl=%d&connect=1", ttl);
00162     ret = url_open(&sap->ann_fd, url, URL_WRONLY);
00163     if (ret) {
00164         ret = AVERROR(EIO);
00165         goto fail;
00166     }
00167 
00168     udp_fd = url_get_file_handle(sap->ann_fd);
00169     if (getsockname(udp_fd, (struct sockaddr*) &localaddr, &addrlen)) {
00170         ret = AVERROR(EIO);
00171         goto fail;
00172     }
00173     if (localaddr.ss_family != AF_INET
00174 #if HAVE_STRUCT_SOCKADDR_IN6
00175         && localaddr.ss_family != AF_INET6
00176 #endif
00177         ) {
00178         av_log(s, AV_LOG_ERROR, "Unsupported protocol family\n");
00179         ret = AVERROR(EIO);
00180         goto fail;
00181     }
00182     sap->ann_size = 8192;
00183     sap->ann = av_mallocz(sap->ann_size);
00184     if (!sap->ann) {
00185         ret = AVERROR(EIO);
00186         goto fail;
00187     }
00188     sap->ann[pos] = (1 << 5);
00189 #if HAVE_STRUCT_SOCKADDR_IN6
00190     if (localaddr.ss_family == AF_INET6)
00191         sap->ann[pos] |= 0x10;
00192 #endif
00193     pos++;
00194     sap->ann[pos++] = 0; /* Authentication length */
00195     AV_WB16(&sap->ann[pos], av_get_random_seed());
00196     pos += 2;
00197     if (localaddr.ss_family == AF_INET) {
00198         memcpy(&sap->ann[pos], &((struct sockaddr_in*)&localaddr)->sin_addr,
00199                sizeof(struct in_addr));
00200         pos += sizeof(struct in_addr);
00201 #if HAVE_STRUCT_SOCKADDR_IN6
00202     } else {
00203         memcpy(&sap->ann[pos], &((struct sockaddr_in6*)&localaddr)->sin6_addr,
00204                sizeof(struct in6_addr));
00205         pos += sizeof(struct in6_addr);
00206 #endif
00207     }
00208 
00209     av_strlcpy(&sap->ann[pos], "application/sdp", sap->ann_size - pos);
00210     pos += strlen(&sap->ann[pos]) + 1;
00211 
00212     if (avf_sdp_create(contexts, s->nb_streams, &sap->ann[pos],
00213                        sap->ann_size - pos)) {
00214         ret = AVERROR_INVALIDDATA;
00215         goto fail;
00216     }
00217     av_freep(&contexts);
00218     av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", &sap->ann[pos]);
00219     pos += strlen(&sap->ann[pos]);
00220     sap->ann_size = pos;
00221 
00222     if (sap->ann_size > url_get_max_packet_size(sap->ann_fd)) {
00223         av_log(s, AV_LOG_ERROR, "Announcement too large to send in one "
00224                                 "packet\n");
00225         goto fail;
00226     }
00227 
00228     return 0;
00229 
00230 fail:
00231     av_free(contexts);
00232     sap_write_close(s);
00233     return ret;
00234 }
00235 
00236 static int sap_write_packet(AVFormatContext *s, AVPacket *pkt)
00237 {
00238     AVFormatContext *rtpctx;
00239     struct SAPState *sap = s->priv_data;
00240     int64_t now = av_gettime();
00241 
00242     if (!sap->last_time || now - sap->last_time > 5000000) {
00243         int ret = url_write(sap->ann_fd, sap->ann, sap->ann_size);
00244         /* Don't abort even if we get "Destination unreachable" */
00245         if (ret < 0 && ret != FF_NETERROR(ECONNREFUSED))
00246             return ret;
00247         sap->last_time = now;
00248     }
00249     rtpctx = s->streams[pkt->stream_index]->priv_data;
00250     return ff_write_chained(rtpctx, 0, pkt, s);
00251 }
00252 
00253 AVOutputFormat sap_muxer = {
00254     "sap",
00255     NULL_IF_CONFIG_SMALL("SAP output format"),
00256     NULL,
00257     NULL,
00258     sizeof(struct SAPState),
00259     CODEC_ID_AAC,
00260     CODEC_ID_MPEG4,
00261     sap_write_header,
00262     sap_write_packet,
00263     sap_write_close,
00264     .flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER,
00265 };
00266