Go to most recent revision | Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 4349 | Serge | 1 | /* |
| 2 | * Session Announcement Protocol (RFC 2974) demuxer |
||
| 3 | * Copyright (c) 2010 Martin Storsjo |
||
| 4 | * |
||
| 5 | * This file is part of FFmpeg. |
||
| 6 | * |
||
| 7 | * FFmpeg is free software; you can redistribute it and/or |
||
| 8 | * modify it under the terms of the GNU Lesser General Public |
||
| 9 | * License as published by the Free Software Foundation; either |
||
| 10 | * version 2.1 of the License, or (at your option) any later version. |
||
| 11 | * |
||
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
||
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
||
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
||
| 15 | * Lesser General Public License for more details. |
||
| 16 | * |
||
| 17 | * You should have received a copy of the GNU Lesser General Public |
||
| 18 | * License along with FFmpeg; if not, write to the Free Software |
||
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
||
| 20 | */ |
||
| 21 | |||
| 22 | #include "avformat.h" |
||
| 23 | #include "libavutil/avstring.h" |
||
| 24 | #include "libavutil/intreadwrite.h" |
||
| 25 | #include "network.h" |
||
| 26 | #include "os_support.h" |
||
| 27 | #include "internal.h" |
||
| 28 | #include "avio_internal.h" |
||
| 29 | #include "url.h" |
||
| 30 | #include "rtpdec.h" |
||
| 31 | #if HAVE_POLL_H |
||
| 32 | #include |
||
| 33 | #endif |
||
| 34 | |||
| 35 | struct SAPState { |
||
| 36 | URLContext *ann_fd; |
||
| 37 | AVFormatContext *sdp_ctx; |
||
| 38 | AVIOContext sdp_pb; |
||
| 39 | uint16_t hash; |
||
| 40 | char *sdp; |
||
| 41 | int eof; |
||
| 42 | }; |
||
| 43 | |||
| 44 | static int sap_probe(AVProbeData *p) |
||
| 45 | { |
||
| 46 | if (av_strstart(p->filename, "sap:", NULL)) |
||
| 47 | return AVPROBE_SCORE_MAX; |
||
| 48 | return 0; |
||
| 49 | } |
||
| 50 | |||
| 51 | static int sap_read_close(AVFormatContext *s) |
||
| 52 | { |
||
| 53 | struct SAPState *sap = s->priv_data; |
||
| 54 | if (sap->sdp_ctx) |
||
| 55 | avformat_close_input(&sap->sdp_ctx); |
||
| 56 | if (sap->ann_fd) |
||
| 57 | ffurl_close(sap->ann_fd); |
||
| 58 | av_freep(&sap->sdp); |
||
| 59 | ff_network_close(); |
||
| 60 | return 0; |
||
| 61 | } |
||
| 62 | |||
| 63 | static int sap_read_header(AVFormatContext *s) |
||
| 64 | { |
||
| 65 | struct SAPState *sap = s->priv_data; |
||
| 66 | char host[1024], path[1024], url[1024]; |
||
| 67 | uint8_t recvbuf[RTP_MAX_PACKET_LENGTH]; |
||
| 68 | int port; |
||
| 69 | int ret, i; |
||
| 70 | AVInputFormat* infmt; |
||
| 71 | |||
| 72 | if (!ff_network_init()) |
||
| 73 | return AVERROR(EIO); |
||
| 74 | |||
| 75 | av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &port, |
||
| 76 | path, sizeof(path), s->filename); |
||
| 77 | if (port < 0) |
||
| 78 | port = 9875; |
||
| 79 | |||
| 80 | if (!host[0]) { |
||
| 81 | /* Listen for announcements on sap.mcast.net if no host was specified */ |
||
| 82 | av_strlcpy(host, "224.2.127.254", sizeof(host)); |
||
| 83 | } |
||
| 84 | |||
| 85 | ff_url_join(url, sizeof(url), "udp", NULL, host, port, "?localport=%d", |
||
| 86 | port); |
||
| 87 | ret = ffurl_open(&sap->ann_fd, url, AVIO_FLAG_READ, |
||
| 88 | &s->interrupt_callback, NULL); |
||
| 89 | if (ret) |
||
| 90 | goto fail; |
||
| 91 | |||
| 92 | while (1) { |
||
| 93 | int addr_type, auth_len; |
||
| 94 | int pos; |
||
| 95 | |||
| 96 | ret = ffurl_read(sap->ann_fd, recvbuf, sizeof(recvbuf) - 1); |
||
| 97 | if (ret == AVERROR(EAGAIN)) |
||
| 98 | continue; |
||
| 99 | if (ret < 0) |
||
| 100 | goto fail; |
||
| 101 | recvbuf[ret] = '\0'; /* Null terminate for easier parsing */ |
||
| 102 | if (ret < 8) { |
||
| 103 | av_log(s, AV_LOG_WARNING, "Received too short packet\n"); |
||
| 104 | continue; |
||
| 105 | } |
||
| 106 | |||
| 107 | if ((recvbuf[0] & 0xe0) != 0x20) { |
||
| 108 | av_log(s, AV_LOG_WARNING, "Unsupported SAP version packet " |
||
| 109 | "received\n"); |
||
| 110 | continue; |
||
| 111 | } |
||
| 112 | |||
| 113 | if (recvbuf[0] & 0x04) { |
||
| 114 | av_log(s, AV_LOG_WARNING, "Received stream deletion " |
||
| 115 | "announcement\n"); |
||
| 116 | continue; |
||
| 117 | } |
||
| 118 | addr_type = recvbuf[0] & 0x10; |
||
| 119 | auth_len = recvbuf[1]; |
||
| 120 | sap->hash = AV_RB16(&recvbuf[2]); |
||
| 121 | pos = 4; |
||
| 122 | if (addr_type) |
||
| 123 | pos += 16; /* IPv6 */ |
||
| 124 | else |
||
| 125 | pos += 4; /* IPv4 */ |
||
| 126 | pos += auth_len * 4; |
||
| 127 | if (pos + 4 >= ret) { |
||
| 128 | av_log(s, AV_LOG_WARNING, "Received too short packet\n"); |
||
| 129 | continue; |
||
| 130 | } |
||
| 131 | #define MIME "application/sdp" |
||
| 132 | if (strcmp(&recvbuf[pos], MIME) == 0) { |
||
| 133 | pos += strlen(MIME) + 1; |
||
| 134 | } else if (strncmp(&recvbuf[pos], "v=0\r\n", 5) == 0) { |
||
| 135 | // Direct SDP without a mime type |
||
| 136 | } else { |
||
| 137 | av_log(s, AV_LOG_WARNING, "Unsupported mime type %s\n", |
||
| 138 | &recvbuf[pos]); |
||
| 139 | continue; |
||
| 140 | } |
||
| 141 | |||
| 142 | sap->sdp = av_strdup(&recvbuf[pos]); |
||
| 143 | break; |
||
| 144 | } |
||
| 145 | |||
| 146 | av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", sap->sdp); |
||
| 147 | ffio_init_context(&sap->sdp_pb, sap->sdp, strlen(sap->sdp), 0, NULL, NULL, |
||
| 148 | NULL, NULL); |
||
| 149 | |||
| 150 | infmt = av_find_input_format("sdp"); |
||
| 151 | if (!infmt) |
||
| 152 | goto fail; |
||
| 153 | sap->sdp_ctx = avformat_alloc_context(); |
||
| 154 | if (!sap->sdp_ctx) { |
||
| 155 | ret = AVERROR(ENOMEM); |
||
| 156 | goto fail; |
||
| 157 | } |
||
| 158 | sap->sdp_ctx->max_delay = s->max_delay; |
||
| 159 | sap->sdp_ctx->pb = &sap->sdp_pb; |
||
| 160 | sap->sdp_ctx->interrupt_callback = s->interrupt_callback; |
||
| 161 | ret = avformat_open_input(&sap->sdp_ctx, "temp.sdp", infmt, NULL); |
||
| 162 | if (ret < 0) |
||
| 163 | goto fail; |
||
| 164 | if (sap->sdp_ctx->ctx_flags & AVFMTCTX_NOHEADER) |
||
| 165 | s->ctx_flags |= AVFMTCTX_NOHEADER; |
||
| 166 | for (i = 0; i < sap->sdp_ctx->nb_streams; i++) { |
||
| 167 | AVStream *st = avformat_new_stream(s, NULL); |
||
| 168 | if (!st) { |
||
| 169 | ret = AVERROR(ENOMEM); |
||
| 170 | goto fail; |
||
| 171 | } |
||
| 172 | st->id = i; |
||
| 173 | avcodec_copy_context(st->codec, sap->sdp_ctx->streams[i]->codec); |
||
| 174 | st->time_base = sap->sdp_ctx->streams[i]->time_base; |
||
| 175 | } |
||
| 176 | |||
| 177 | return 0; |
||
| 178 | |||
| 179 | fail: |
||
| 180 | sap_read_close(s); |
||
| 181 | return ret; |
||
| 182 | } |
||
| 183 | |||
| 184 | static int sap_fetch_packet(AVFormatContext *s, AVPacket *pkt) |
||
| 185 | { |
||
| 186 | struct SAPState *sap = s->priv_data; |
||
| 187 | int fd = ffurl_get_file_handle(sap->ann_fd); |
||
| 188 | int n, ret; |
||
| 189 | struct pollfd p = {fd, POLLIN, 0}; |
||
| 190 | uint8_t recvbuf[RTP_MAX_PACKET_LENGTH]; |
||
| 191 | |||
| 192 | if (sap->eof) |
||
| 193 | return AVERROR_EOF; |
||
| 194 | |||
| 195 | while (1) { |
||
| 196 | n = poll(&p, 1, 0); |
||
| 197 | if (n <= 0 || !(p.revents & POLLIN)) |
||
| 198 | break; |
||
| 199 | ret = ffurl_read(sap->ann_fd, recvbuf, sizeof(recvbuf)); |
||
| 200 | if (ret >= 8) { |
||
| 201 | uint16_t hash = AV_RB16(&recvbuf[2]); |
||
| 202 | /* Should ideally check the source IP address, too */ |
||
| 203 | if (recvbuf[0] & 0x04 && hash == sap->hash) { |
||
| 204 | /* Stream deletion */ |
||
| 205 | sap->eof = 1; |
||
| 206 | return AVERROR_EOF; |
||
| 207 | } |
||
| 208 | } |
||
| 209 | } |
||
| 210 | ret = av_read_frame(sap->sdp_ctx, pkt); |
||
| 211 | if (ret < 0) |
||
| 212 | return ret; |
||
| 213 | if (s->ctx_flags & AVFMTCTX_NOHEADER) { |
||
| 214 | while (sap->sdp_ctx->nb_streams > s->nb_streams) { |
||
| 215 | int i = s->nb_streams; |
||
| 216 | AVStream *st = avformat_new_stream(s, NULL); |
||
| 217 | if (!st) { |
||
| 218 | av_free_packet(pkt); |
||
| 219 | return AVERROR(ENOMEM); |
||
| 220 | } |
||
| 221 | st->id = i; |
||
| 222 | avcodec_copy_context(st->codec, sap->sdp_ctx->streams[i]->codec); |
||
| 223 | st->time_base = sap->sdp_ctx->streams[i]->time_base; |
||
| 224 | } |
||
| 225 | } |
||
| 226 | return ret; |
||
| 227 | } |
||
| 228 | |||
| 229 | AVInputFormat ff_sap_demuxer = { |
||
| 230 | .name = "sap", |
||
| 231 | .long_name = NULL_IF_CONFIG_SMALL("SAP input"), |
||
| 232 | .priv_data_size = sizeof(struct SAPState), |
||
| 233 | .read_probe = sap_probe, |
||
| 234 | .read_header = sap_read_header, |
||
| 235 | .read_packet = sap_fetch_packet, |
||
| 236 | .read_close = sap_read_close, |
||
| 237 | .flags = AVFMT_NOFILE, |
||
| 238 | }; |