1/*
2 * copyright (c) 2007 Luca Abeni
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#include <string.h>
22#include "libavutil/avstring.h"
23#include "libavutil/base64.h"
24#include "libavutil/dict.h"
25#include "libavutil/parseutils.h"
26#include "libavutil/opt.h"
27#include "libavcodec/xiph.h"
28#include "libavcodec/mpeg4audio.h"
29#include "avformat.h"
30#include "internal.h"
31#include "avc.h"
32#include "rtp.h"
33#if CONFIG_NETWORK
34#include "network.h"
35#endif
36
37#if CONFIG_RTP_MUXER
38#define MAX_EXTRADATA_SIZE ((INT_MAX - 10) / 2)
39
40struct sdp_session_level {
41    int sdp_version;      /**< protocol version (currently 0) */
42    int id;               /**< session ID */
43    int version;          /**< session version */
44    int start_time;       /**< session start time (NTP time, in seconds),
45                               or 0 in case of permanent session */
46    int end_time;         /**< session end time (NTP time, in seconds),
47                               or 0 if the session is not bounded */
48    int ttl;              /**< TTL, in case of multicast stream */
49    const char *user;     /**< username of the session's creator */
50    const char *src_addr; /**< IP address of the machine from which the session was created */
51    const char *src_type; /**< address type of src_addr */
52    const char *dst_addr; /**< destination IP address (can be multicast) */
53    const char *dst_type; /**< destination IP address type */
54    const char *name;     /**< session name (can be an empty string) */
55};
56
57static void sdp_write_address(char *buff, int size, const char *dest_addr,
58                              const char *dest_type, int ttl)
59{
60    if (dest_addr) {
61        if (!dest_type)
62            dest_type = "IP4";
63        if (ttl > 0 && !strcmp(dest_type, "IP4")) {
64            /* The TTL should only be specified for IPv4 multicast addresses,
65             * not for IPv6. */
66            av_strlcatf(buff, size, "c=IN %s %s/%d\r\n", dest_type, dest_addr, ttl);
67        } else {
68            av_strlcatf(buff, size, "c=IN %s %s\r\n", dest_type, dest_addr);
69        }
70    }
71}
72
73static void sdp_write_header(char *buff, int size, struct sdp_session_level *s)
74{
75    av_strlcatf(buff, size, "v=%d\r\n"
76                            "o=- %d %d IN %s %s\r\n"
77                            "s=%s\r\n",
78                            s->sdp_version,
79                            s->id, s->version, s->src_type, s->src_addr,
80                            s->name);
81    sdp_write_address(buff, size, s->dst_addr, s->dst_type, s->ttl);
82    av_strlcatf(buff, size, "t=%d %d\r\n"
83                            "a=tool:libavformat " AV_STRINGIFY(LIBAVFORMAT_VERSION) "\r\n",
84                            s->start_time, s->end_time);
85}
86
87#if CONFIG_NETWORK
88static int resolve_destination(char *dest_addr, int size, char *type,
89                               int type_size)
90{
91    struct addrinfo hints = { 0 }, *ai;
92    int is_multicast;
93
94    av_strlcpy(type, "IP4", type_size);
95    if (!dest_addr[0])
96        return 0;
97
98    /* Resolve the destination, since it must be written
99     * as a numeric IP address in the SDP. */
100
101    if (getaddrinfo(dest_addr, NULL, &hints, &ai))
102        return 0;
103    getnameinfo(ai->ai_addr, ai->ai_addrlen, dest_addr, size,
104                NULL, 0, NI_NUMERICHOST);
105#ifdef AF_INET6
106    if (ai->ai_family == AF_INET6)
107        av_strlcpy(type, "IP6", type_size);
108#endif
109    is_multicast = ff_is_multicast_address(ai->ai_addr);
110    freeaddrinfo(ai);
111    return is_multicast;
112}
113#else
114static int resolve_destination(char *dest_addr, int size, char *type,
115                               int type_size)
116{
117    return 0;
118}
119#endif
120
121static int sdp_get_address(char *dest_addr, int size, int *ttl, const char *url)
122{
123    int port;
124    const char *p;
125    char proto[32];
126
127    av_url_split(proto, sizeof(proto), NULL, 0, dest_addr, size, &port, NULL, 0, url);
128
129    *ttl = 0;
130
131    if (strcmp(proto, "rtp") && strcmp(proto, "srtp")) {
132        /* The url isn't for the actual rtp sessions,
133         * don't parse out anything else than the destination.
134         */
135        return 0;
136    }
137
138    p = strchr(url, '?');
139    if (p) {
140        char buff[64];
141
142        if (av_find_info_tag(buff, sizeof(buff), "ttl", p)) {
143            *ttl = strtol(buff, NULL, 10);
144        } else {
145            *ttl = 5;
146        }
147    }
148
149    return port;
150}
151
152#define MAX_PSET_SIZE 1024
153static char *extradata2psets(AVCodecContext *c)
154{
155    char *psets, *p;
156    const uint8_t *r;
157    static const char pset_string[] = "; sprop-parameter-sets=";
158    static const char profile_string[] = "; profile-level-id=";
159    uint8_t *orig_extradata = NULL;
160    int orig_extradata_size = 0;
161    const uint8_t *sps = NULL, *sps_end;
162
163    if (c->extradata_size > MAX_EXTRADATA_SIZE) {
164        av_log(c, AV_LOG_ERROR, "Too much extradata!\n");
165
166        return NULL;
167    }
168    if (c->extradata[0] == 1) {
169        uint8_t *dummy_p;
170        int dummy_int;
171        AVBitStreamFilterContext *bsfc= av_bitstream_filter_init("h264_mp4toannexb");
172
173        if (!bsfc) {
174            av_log(c, AV_LOG_ERROR, "Cannot open the h264_mp4toannexb BSF!\n");
175
176            return NULL;
177        }
178
179        orig_extradata_size = c->extradata_size;
180        orig_extradata = av_mallocz(orig_extradata_size +
181                                    FF_INPUT_BUFFER_PADDING_SIZE);
182        if (!orig_extradata) {
183            av_bitstream_filter_close(bsfc);
184            return NULL;
185        }
186        memcpy(orig_extradata, c->extradata, orig_extradata_size);
187        av_bitstream_filter_filter(bsfc, c, NULL, &dummy_p, &dummy_int, NULL, 0, 0);
188        av_bitstream_filter_close(bsfc);
189    }
190
191    psets = av_mallocz(MAX_PSET_SIZE);
192    if (psets == NULL) {
193        av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the parameter sets.\n");
194        av_free(orig_extradata);
195        return NULL;
196    }
197    memcpy(psets, pset_string, strlen(pset_string));
198    p = psets + strlen(pset_string);
199    r = ff_avc_find_startcode(c->extradata, c->extradata + c->extradata_size);
200    while (r < c->extradata + c->extradata_size) {
201        const uint8_t *r1;
202        uint8_t nal_type;
203
204        while (!*(r++));
205        nal_type = *r & 0x1f;
206        r1 = ff_avc_find_startcode(r, c->extradata + c->extradata_size);
207        if (nal_type != 7 && nal_type != 8) { /* Only output SPS and PPS */
208            r = r1;
209            continue;
210        }
211        if (p != (psets + strlen(pset_string))) {
212            *p = ',';
213            p++;
214        }
215        if (!sps) {
216            sps = r;
217            sps_end = r1;
218        }
219        if (av_base64_encode(p, MAX_PSET_SIZE - (p - psets), r, r1 - r) == NULL) {
220            av_log(c, AV_LOG_ERROR, "Cannot Base64-encode %"PTRDIFF_SPECIFIER" %"PTRDIFF_SPECIFIER"!\n", MAX_PSET_SIZE - (p - psets), r1 - r);
221            av_free(psets);
222
223            return NULL;
224        }
225        p += strlen(p);
226        r = r1;
227    }
228    if (sps && sps_end - sps >= 4) {
229        memcpy(p, profile_string, strlen(profile_string));
230        p += strlen(p);
231        ff_data_to_hex(p, sps + 1, 3, 0);
232        p[6] = '\0';
233    }
234    if (orig_extradata) {
235        av_free(c->extradata);
236        c->extradata      = orig_extradata;
237        c->extradata_size = orig_extradata_size;
238    }
239
240    return psets;
241}
242
243static char *extradata2config(AVCodecContext *c)
244{
245    char *config;
246
247    if (c->extradata_size > MAX_EXTRADATA_SIZE) {
248        av_log(c, AV_LOG_ERROR, "Too much extradata!\n");
249
250        return NULL;
251    }
252    config = av_malloc(10 + c->extradata_size * 2);
253    if (config == NULL) {
254        av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n");
255        return NULL;
256    }
257    memcpy(config, "; config=", 9);
258    ff_data_to_hex(config + 9, c->extradata, c->extradata_size, 0);
259    config[9 + c->extradata_size * 2] = 0;
260
261    return config;
262}
263
264static char *xiph_extradata2config(AVCodecContext *c)
265{
266    char *config, *encoded_config;
267    uint8_t *header_start[3];
268    int headers_len, header_len[3], config_len;
269    int first_header_size;
270
271    switch (c->codec_id) {
272    case AV_CODEC_ID_THEORA:
273        first_header_size = 42;
274        break;
275    case AV_CODEC_ID_VORBIS:
276        first_header_size = 30;
277        break;
278    default:
279        av_log(c, AV_LOG_ERROR, "Unsupported Xiph codec ID\n");
280        return NULL;
281    }
282
283    if (avpriv_split_xiph_headers(c->extradata, c->extradata_size,
284                              first_header_size, header_start,
285                              header_len) < 0) {
286        av_log(c, AV_LOG_ERROR, "Extradata corrupt.\n");
287        return NULL;
288    }
289
290    headers_len = header_len[0] + header_len[2];
291    config_len = 4 +          // count
292                 3 +          // ident
293                 2 +          // packet size
294                 1 +          // header count
295                 2 +          // header size
296                 headers_len; // and the rest
297
298    config = av_malloc(config_len);
299    if (!config)
300        goto xiph_fail;
301
302    encoded_config = av_malloc(AV_BASE64_SIZE(config_len));
303    if (!encoded_config) {
304        av_free(config);
305        goto xiph_fail;
306    }
307
308    config[0] = config[1] = config[2] = 0;
309    config[3] = 1;
310    config[4] = (RTP_XIPH_IDENT >> 16) & 0xff;
311    config[5] = (RTP_XIPH_IDENT >>  8) & 0xff;
312    config[6] = (RTP_XIPH_IDENT      ) & 0xff;
313    config[7] = (headers_len >> 8) & 0xff;
314    config[8] = headers_len & 0xff;
315    config[9] = 2;
316    config[10] = header_len[0];
317    config[11] = 0; // size of comment header; nonexistent
318    memcpy(config + 12, header_start[0], header_len[0]);
319    memcpy(config + 12 + header_len[0], header_start[2], header_len[2]);
320
321    av_base64_encode(encoded_config, AV_BASE64_SIZE(config_len),
322                     config, config_len);
323    av_free(config);
324
325    return encoded_config;
326
327xiph_fail:
328    av_log(c, AV_LOG_ERROR,
329           "Not enough memory for configuration string\n");
330    return NULL;
331}
332
333static int latm_context2profilelevel(AVCodecContext *c)
334{
335    /* MP4A-LATM
336     * The RTP payload format specification is described in RFC 3016
337     * The encoding specifications are provided in ISO/IEC 14496-3 */
338
339    int profile_level = 0x2B;
340
341    /* TODO: AAC Profile only supports AAC LC Object Type.
342     * Different Object Types should implement different Profile Levels */
343
344    if (c->sample_rate <= 24000) {
345        if (c->channels <= 2)
346            profile_level = 0x28; // AAC Profile, Level 1
347    } else if (c->sample_rate <= 48000) {
348        if (c->channels <= 2) {
349            profile_level = 0x29; // AAC Profile, Level 2
350        } else if (c->channels <= 5) {
351            profile_level = 0x2A; // AAC Profile, Level 4
352        }
353    } else if (c->sample_rate <= 96000) {
354        if (c->channels <= 5) {
355            profile_level = 0x2B; // AAC Profile, Level 5
356        }
357    }
358
359    return profile_level;
360}
361
362static char *latm_context2config(AVCodecContext *c)
363{
364    /* MP4A-LATM
365     * The RTP payload format specification is described in RFC 3016
366     * The encoding specifications are provided in ISO/IEC 14496-3 */
367
368    uint8_t config_byte[6];
369    int rate_index;
370    char *config;
371
372    for (rate_index = 0; rate_index < 16; rate_index++)
373        if (avpriv_mpeg4audio_sample_rates[rate_index] == c->sample_rate)
374            break;
375    if (rate_index == 16) {
376        av_log(c, AV_LOG_ERROR, "Unsupported sample rate\n");
377        return NULL;
378    }
379
380    config_byte[0] = 0x40;
381    config_byte[1] = 0;
382    config_byte[2] = 0x20 | rate_index;
383    config_byte[3] = c->channels << 4;
384    config_byte[4] = 0x3f;
385    config_byte[5] = 0xc0;
386
387    config = av_malloc(6*2+1);
388    if (!config) {
389        av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n");
390        return NULL;
391    }
392    ff_data_to_hex(config, config_byte, 6, 1);
393    config[12] = 0;
394
395    return config;
396}
397
398static char *sdp_write_media_attributes(char *buff, int size, AVCodecContext *c, int payload_type, AVFormatContext *fmt)
399{
400    char *config = NULL;
401
402    switch (c->codec_id) {
403        case AV_CODEC_ID_H264: {
404            int mode = 1;
405            if (fmt && fmt->oformat && fmt->oformat->priv_class &&
406                av_opt_flag_is_set(fmt->priv_data, "rtpflags", "h264_mode0"))
407                mode = 0;
408            if (c->extradata_size) {
409                config = extradata2psets(c);
410            }
411            av_strlcatf(buff, size, "a=rtpmap:%d H264/90000\r\n"
412                                    "a=fmtp:%d packetization-mode=%d%s\r\n",
413                                     payload_type,
414                                     payload_type, mode, config ? config : "");
415            break;
416        }
417        case AV_CODEC_ID_H263:
418        case AV_CODEC_ID_H263P:
419            /* a=framesize is required by 3GPP TS 26.234 (PSS). It
420             * actually specifies the maximum video size, but we only know
421             * the current size. This is required for playback on Android
422             * stagefright and on Samsung bada. */
423            if (!fmt || !fmt->oformat->priv_class ||
424                !av_opt_flag_is_set(fmt->priv_data, "rtpflags", "rfc2190") ||
425                c->codec_id == AV_CODEC_ID_H263P)
426            av_strlcatf(buff, size, "a=rtpmap:%d H263-2000/90000\r\n"
427                                    "a=framesize:%d %d-%d\r\n",
428                                    payload_type,
429                                    payload_type, c->width, c->height);
430            break;
431        case AV_CODEC_ID_MPEG4:
432            if (c->extradata_size) {
433                config = extradata2config(c);
434            }
435            av_strlcatf(buff, size, "a=rtpmap:%d MP4V-ES/90000\r\n"
436                                    "a=fmtp:%d profile-level-id=1%s\r\n",
437                                     payload_type,
438                                     payload_type, config ? config : "");
439            break;
440        case AV_CODEC_ID_AAC:
441            if (fmt && fmt->oformat && fmt->oformat->priv_class &&
442                av_opt_flag_is_set(fmt->priv_data, "rtpflags", "latm")) {
443                config = latm_context2config(c);
444                if (!config)
445                    return NULL;
446                av_strlcatf(buff, size, "a=rtpmap:%d MP4A-LATM/%d/%d\r\n"
447                                        "a=fmtp:%d profile-level-id=%d;cpresent=0;config=%s\r\n",
448                                         payload_type, c->sample_rate, c->channels,
449                                         payload_type, latm_context2profilelevel(c), config);
450            } else {
451                if (c->extradata_size) {
452                    config = extradata2config(c);
453                } else {
454                    /* FIXME: maybe we can forge config information based on the
455                     *        codec parameters...
456                     */
457                    av_log(c, AV_LOG_ERROR, "AAC with no global headers is currently not supported.\n");
458                    return NULL;
459                }
460                if (config == NULL) {
461                    return NULL;
462                }
463                av_strlcatf(buff, size, "a=rtpmap:%d MPEG4-GENERIC/%d/%d\r\n"
464                                        "a=fmtp:%d profile-level-id=1;"
465                                        "mode=AAC-hbr;sizelength=13;indexlength=3;"
466                                        "indexdeltalength=3%s\r\n",
467                                         payload_type, c->sample_rate, c->channels,
468                                         payload_type, config);
469            }
470            break;
471        case AV_CODEC_ID_PCM_S16BE:
472            if (payload_type >= RTP_PT_PRIVATE)
473                av_strlcatf(buff, size, "a=rtpmap:%d L16/%d/%d\r\n",
474                                         payload_type,
475                                         c->sample_rate, c->channels);
476            break;
477        case AV_CODEC_ID_PCM_MULAW:
478            if (payload_type >= RTP_PT_PRIVATE)
479                av_strlcatf(buff, size, "a=rtpmap:%d PCMU/%d/%d\r\n",
480                                         payload_type,
481                                         c->sample_rate, c->channels);
482            break;
483        case AV_CODEC_ID_PCM_ALAW:
484            if (payload_type >= RTP_PT_PRIVATE)
485                av_strlcatf(buff, size, "a=rtpmap:%d PCMA/%d/%d\r\n",
486                                         payload_type,
487                                         c->sample_rate, c->channels);
488            break;
489        case AV_CODEC_ID_AMR_NB:
490            av_strlcatf(buff, size, "a=rtpmap:%d AMR/%d/%d\r\n"
491                                    "a=fmtp:%d octet-align=1\r\n",
492                                     payload_type, c->sample_rate, c->channels,
493                                     payload_type);
494            break;
495        case AV_CODEC_ID_AMR_WB:
496            av_strlcatf(buff, size, "a=rtpmap:%d AMR-WB/%d/%d\r\n"
497                                    "a=fmtp:%d octet-align=1\r\n",
498                                     payload_type, c->sample_rate, c->channels,
499                                     payload_type);
500            break;
501        case AV_CODEC_ID_VORBIS:
502            if (c->extradata_size)
503                config = xiph_extradata2config(c);
504            else
505                av_log(c, AV_LOG_ERROR, "Vorbis configuration info missing\n");
506            if (!config)
507                return NULL;
508
509            av_strlcatf(buff, size, "a=rtpmap:%d vorbis/%d/%d\r\n"
510                                    "a=fmtp:%d configuration=%s\r\n",
511                                    payload_type, c->sample_rate, c->channels,
512                                    payload_type, config);
513            break;
514        case AV_CODEC_ID_THEORA: {
515            const char *pix_fmt;
516            switch (c->pix_fmt) {
517            case AV_PIX_FMT_YUV420P:
518                pix_fmt = "YCbCr-4:2:0";
519                break;
520            case AV_PIX_FMT_YUV422P:
521                pix_fmt = "YCbCr-4:2:2";
522                break;
523            case AV_PIX_FMT_YUV444P:
524                pix_fmt = "YCbCr-4:4:4";
525                break;
526            default:
527                av_log(c, AV_LOG_ERROR, "Unsupported pixel format.\n");
528                return NULL;
529            }
530
531            if (c->extradata_size)
532                config = xiph_extradata2config(c);
533            else
534                av_log(c, AV_LOG_ERROR, "Theora configuation info missing\n");
535            if (!config)
536                return NULL;
537
538            av_strlcatf(buff, size, "a=rtpmap:%d theora/90000\r\n"
539                                    "a=fmtp:%d delivery-method=inline; "
540                                    "width=%d; height=%d; sampling=%s; "
541                                    "configuration=%s\r\n",
542                                    payload_type, payload_type,
543                                    c->width, c->height, pix_fmt, config);
544            break;
545        }
546        case AV_CODEC_ID_VP8:
547            av_strlcatf(buff, size, "a=rtpmap:%d VP8/90000\r\n",
548                                     payload_type);
549            break;
550        case AV_CODEC_ID_MJPEG:
551            if (payload_type >= RTP_PT_PRIVATE)
552                av_strlcatf(buff, size, "a=rtpmap:%d JPEG/90000\r\n",
553                                         payload_type);
554            break;
555        case AV_CODEC_ID_ADPCM_G722:
556            if (payload_type >= RTP_PT_PRIVATE)
557                av_strlcatf(buff, size, "a=rtpmap:%d G722/%d/%d\r\n",
558                                         payload_type,
559                                         8000, c->channels);
560            break;
561        case AV_CODEC_ID_ADPCM_G726: {
562            if (payload_type >= RTP_PT_PRIVATE)
563                av_strlcatf(buff, size, "a=rtpmap:%d G726-%d/%d\r\n",
564                                         payload_type,
565                                         c->bits_per_coded_sample*8,
566                                         c->sample_rate);
567            break;
568        }
569        case AV_CODEC_ID_ILBC:
570            av_strlcatf(buff, size, "a=rtpmap:%d iLBC/%d\r\n"
571                                    "a=fmtp:%d mode=%d\r\n",
572                                     payload_type, c->sample_rate,
573                                     payload_type, c->block_align == 38 ? 20 : 30);
574            break;
575        case AV_CODEC_ID_SPEEX:
576            av_strlcatf(buff, size, "a=rtpmap:%d speex/%d\r\n",
577                                     payload_type, c->sample_rate);
578            if (c->codec) {
579                const char *mode;
580                uint64_t vad_option;
581
582                if (c->flags & CODEC_FLAG_QSCALE)
583                      mode = "on";
584                else if (!av_opt_get_int(c, "vad", AV_OPT_FLAG_ENCODING_PARAM, &vad_option) && vad_option)
585                      mode = "vad";
586                else
587                      mode = "off";
588
589                av_strlcatf(buff, size, "a=fmtp:%d vbr=%s\r\n",
590                                        payload_type, mode);
591            }
592            break;
593        case AV_CODEC_ID_OPUS:
594            av_strlcatf(buff, size, "a=rtpmap:%d opus/48000\r\n",
595                                     payload_type);
596            break;
597        default:
598            /* Nothing special to do here... */
599            break;
600    }
601
602    av_free(config);
603
604    return buff;
605}
606
607void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
608                        const char *dest_addr, const char *dest_type,
609                        int port, int ttl, AVFormatContext *fmt)
610{
611    AVCodecContext *c = st->codec;
612    const char *type;
613    int payload_type;
614
615    payload_type = ff_rtp_get_payload_type(fmt, c, idx);
616
617    switch (c->codec_type) {
618        case AVMEDIA_TYPE_VIDEO   : type = "video"      ; break;
619        case AVMEDIA_TYPE_AUDIO   : type = "audio"      ; break;
620        case AVMEDIA_TYPE_SUBTITLE: type = "text"       ; break;
621        default                 : type = "application"; break;
622    }
623
624    av_strlcatf(buff, size, "m=%s %d RTP/AVP %d\r\n", type, port, payload_type);
625    sdp_write_address(buff, size, dest_addr, dest_type, ttl);
626    if (c->bit_rate) {
627        av_strlcatf(buff, size, "b=AS:%d\r\n", c->bit_rate / 1000);
628    }
629
630    sdp_write_media_attributes(buff, size, c, payload_type, fmt);
631}
632
633int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
634{
635    AVDictionaryEntry *title = av_dict_get(ac[0]->metadata, "title", NULL, 0);
636    struct sdp_session_level s = { 0 };
637    int i, j, port, ttl, is_multicast, index = 0;
638    char dst[32], dst_type[5];
639
640    memset(buf, 0, size);
641    s.user = "-";
642    s.src_addr = "127.0.0.1";    /* FIXME: Properly set this */
643    s.src_type = "IP4";
644    s.name = title ? title->value : "No Name";
645
646    port = 0;
647    ttl = 0;
648    if (n_files == 1) {
649        port = sdp_get_address(dst, sizeof(dst), &ttl, ac[0]->filename);
650        is_multicast = resolve_destination(dst, sizeof(dst), dst_type,
651                                           sizeof(dst_type));
652        if (!is_multicast)
653            ttl = 0;
654        if (dst[0]) {
655            s.dst_addr = dst;
656            s.dst_type = dst_type;
657            s.ttl = ttl;
658            if (!strcmp(dst_type, "IP6")) {
659                s.src_addr = "::1";
660                s.src_type = "IP6";
661            }
662        }
663    }
664    sdp_write_header(buf, size, &s);
665
666    dst[0] = 0;
667    for (i = 0; i < n_files; i++) {
668        if (n_files != 1) {
669            port = sdp_get_address(dst, sizeof(dst), &ttl, ac[i]->filename);
670            is_multicast = resolve_destination(dst, sizeof(dst), dst_type,
671                                               sizeof(dst_type));
672            if (!is_multicast)
673                ttl = 0;
674        }
675        for (j = 0; j < ac[i]->nb_streams; j++) {
676            ff_sdp_write_media(buf, size, ac[i]->streams[j], index++,
677                               dst[0] ? dst : NULL, dst_type,
678                               (port > 0) ? port + j * 2 : 0,
679                               ttl, ac[i]);
680            if (port <= 0) {
681                av_strlcatf(buf, size,
682                                   "a=control:streamid=%d\r\n", i + j);
683            }
684            if (ac[i]->pb && ac[i]->pb->av_class) {
685                uint8_t *crypto_suite = NULL, *crypto_params = NULL;
686                av_opt_get(ac[i]->pb, "srtp_out_suite",  AV_OPT_SEARCH_CHILDREN,
687                           &crypto_suite);
688                av_opt_get(ac[i]->pb, "srtp_out_params", AV_OPT_SEARCH_CHILDREN,
689                           &crypto_params);
690                if (crypto_suite && crypto_suite[0])
691                    av_strlcatf(buf, size,
692                                "a=crypto:1 %s inline:%s\r\n",
693                                crypto_suite, crypto_params);
694                av_free(crypto_suite);
695                av_free(crypto_params);
696            }
697        }
698    }
699
700    return 0;
701}
702#else
703int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
704{
705    return AVERROR(ENOSYS);
706}
707
708void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
709                        const char *dest_addr, const char *dest_type,
710                        int port, int ttl, AVFormatContext *fmt)
711{
712}
713#endif
714