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 "libavutil/avstring.h"
22#include "libavutil/base64.h"
23#include "avformat.h"
24#include "internal.h"
25#include "avc.h"
26#include "rtp.h"
27
28#if CONFIG_RTP_MUXER
29#define MAX_EXTRADATA_SIZE ((INT_MAX - 10) / 2)
30
31struct sdp_session_level {
32    int sdp_version;      /**< protocol version (currently 0) */
33    int id;               /**< session ID */
34    int version;          /**< session version */
35    int start_time;       /**< session start time (NTP time, in seconds),
36                               or 0 in case of permanent session */
37    int end_time;         /**< session end time (NTP time, in seconds),
38                               or 0 if the session is not bounded */
39    int ttl;              /**< TTL, in case of multicast stream */
40    const char *user;     /**< username of the session's creator */
41    const char *src_addr; /**< IP address of the machine from which the session was created */
42    const char *dst_addr; /**< destination IP address (can be multicast) */
43    const char *name;     /**< session name (can be an empty string) */
44};
45
46static void sdp_write_address(char *buff, int size, const char *dest_addr, int ttl)
47{
48    if (dest_addr) {
49        if (ttl > 0) {
50            av_strlcatf(buff, size, "c=IN IP4 %s/%d\r\n", dest_addr, ttl);
51        } else {
52            av_strlcatf(buff, size, "c=IN IP4 %s\r\n", dest_addr);
53        }
54    }
55}
56
57static void sdp_write_header(char *buff, int size, struct sdp_session_level *s)
58{
59    av_strlcatf(buff, size, "v=%d\r\n"
60                            "o=- %d %d IN IP4 %s\r\n"
61                            "t=%d %d\r\n"
62                            "s=%s\r\n"
63                            "a=tool:libavformat " AV_STRINGIFY(LIBAVFORMAT_VERSION) "\r\n",
64                            s->sdp_version,
65                            s->id, s->version, s->src_addr,
66                            s->start_time, s->end_time,
67                            s->name);
68    sdp_write_address(buff, size, s->dst_addr, s->ttl);
69}
70
71static int sdp_get_address(char *dest_addr, int size, int *ttl, const char *url)
72{
73    int port;
74    const char *p;
75
76    url_split(NULL, 0, NULL, 0, dest_addr, size, &port, NULL, 0, url);
77
78    *ttl = 0;
79    p = strchr(url, '?');
80    if (p) {
81        char buff[64];
82        int is_multicast = find_info_tag(buff, sizeof(buff), "multicast", p);
83
84        if (is_multicast) {
85            if (find_info_tag(buff, sizeof(buff), "ttl", p)) {
86                *ttl = strtol(buff, NULL, 10);
87            } else {
88                *ttl = 5;
89            }
90        }
91    }
92
93    return port;
94}
95
96#define MAX_PSET_SIZE 1024
97static char *extradata2psets(AVCodecContext *c)
98{
99    char *psets, *p;
100    const uint8_t *r;
101    const char *pset_string = "; sprop-parameter-sets=";
102
103    if (c->extradata_size > MAX_EXTRADATA_SIZE) {
104        av_log(c, AV_LOG_ERROR, "Too much extradata!\n");
105
106        return NULL;
107    }
108
109    psets = av_mallocz(MAX_PSET_SIZE);
110    if (psets == NULL) {
111        av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the parameter sets.\n");
112        return NULL;
113    }
114    memcpy(psets, pset_string, strlen(pset_string));
115    p = psets + strlen(pset_string);
116    r = ff_avc_find_startcode(c->extradata, c->extradata + c->extradata_size);
117    while (r < c->extradata + c->extradata_size) {
118        const uint8_t *r1;
119
120        while (!*(r++));
121        r1 = ff_avc_find_startcode(r, c->extradata + c->extradata_size);
122        if (p != (psets + strlen(pset_string))) {
123            *p = ',';
124            p++;
125        }
126        if (av_base64_encode(p, MAX_PSET_SIZE - (p - psets), r, r1 - r) == NULL) {
127            av_log(c, AV_LOG_ERROR, "Cannot Base64-encode %td %td!\n", MAX_PSET_SIZE - (p - psets), r1 - r);
128            av_free(psets);
129
130            return NULL;
131        }
132        p += strlen(p);
133        r = r1;
134    }
135
136    return psets;
137}
138
139static char *extradata2config(AVCodecContext *c)
140{
141    char *config;
142
143    if (c->extradata_size > MAX_EXTRADATA_SIZE) {
144        av_log(c, AV_LOG_ERROR, "Too much extradata!\n");
145
146        return NULL;
147    }
148    config = av_malloc(10 + c->extradata_size * 2);
149    if (config == NULL) {
150        av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n");
151        return NULL;
152    }
153    memcpy(config, "; config=", 9);
154    ff_data_to_hex(config + 9, c->extradata, c->extradata_size);
155    config[9 + c->extradata_size * 2] = 0;
156
157    return config;
158}
159
160static char *sdp_write_media_attributes(char *buff, int size, AVCodecContext *c, int payload_type)
161{
162    char *config = NULL;
163
164    switch (c->codec_id) {
165        case CODEC_ID_H264:
166            if (c->extradata_size) {
167                config = extradata2psets(c);
168            }
169            av_strlcatf(buff, size, "a=rtpmap:%d H264/90000\r\n"
170                                    "a=fmtp:%d packetization-mode=1%s\r\n",
171                                     payload_type,
172                                     payload_type, config ? config : "");
173            break;
174        case CODEC_ID_MPEG4:
175            if (c->extradata_size) {
176                config = extradata2config(c);
177            }
178            av_strlcatf(buff, size, "a=rtpmap:%d MP4V-ES/90000\r\n"
179                                    "a=fmtp:%d profile-level-id=1%s\r\n",
180                                     payload_type,
181                                     payload_type, config ? config : "");
182            break;
183        case CODEC_ID_AAC:
184            if (c->extradata_size) {
185                config = extradata2config(c);
186            } else {
187                /* FIXME: maybe we can forge config information based on the
188                 *        codec parameters...
189                 */
190                av_log(c, AV_LOG_ERROR, "AAC with no global headers is currently not supported.\n");
191                return NULL;
192            }
193            if (config == NULL) {
194                return NULL;
195            }
196            av_strlcatf(buff, size, "a=rtpmap:%d MPEG4-GENERIC/%d/%d\r\n"
197                                    "a=fmtp:%d profile-level-id=1;"
198                                    "mode=AAC-hbr;sizelength=13;indexlength=3;"
199                                    "indexdeltalength=3%s\r\n",
200                                     payload_type, c->sample_rate, c->channels,
201                                     payload_type, config);
202            break;
203        case CODEC_ID_PCM_S16BE:
204            if (payload_type >= 96)
205                av_strlcatf(buff, size, "a=rtpmap:%d L16/%d/%d\r\n",
206                                         payload_type,
207                                         c->sample_rate, c->channels);
208            break;
209        case CODEC_ID_PCM_MULAW:
210            if (payload_type >= 96)
211                av_strlcatf(buff, size, "a=rtpmap:%d PCMU/%d/%d\r\n",
212                                         payload_type,
213                                         c->sample_rate, c->channels);
214            break;
215        case CODEC_ID_PCM_ALAW:
216            if (payload_type >= 96)
217                av_strlcatf(buff, size, "a=rtpmap:%d PCMA/%d/%d\r\n",
218                                         payload_type,
219                                         c->sample_rate, c->channels);
220            break;
221        default:
222            /* Nothing special to do here... */
223            break;
224    }
225
226    av_free(config);
227
228    return buff;
229}
230
231static void sdp_write_media(char *buff, int size, AVCodecContext *c, const char *dest_addr, int port, int ttl)
232{
233    const char *type;
234    int payload_type;
235
236    payload_type = ff_rtp_get_payload_type(c);
237    if (payload_type < 0) {
238        payload_type = 96;  /* FIXME: how to assign a private pt? rtp.c is broken too */
239    }
240
241    switch (c->codec_type) {
242        case CODEC_TYPE_VIDEO   : type = "video"      ; break;
243        case CODEC_TYPE_AUDIO   : type = "audio"      ; break;
244        case CODEC_TYPE_SUBTITLE: type = "text"       ; break;
245        default                 : type = "application"; break;
246    }
247
248    av_strlcatf(buff, size, "m=%s %d RTP/AVP %d\r\n", type, port, payload_type);
249    sdp_write_address(buff, size, dest_addr, ttl);
250    if (c->bit_rate) {
251        av_strlcatf(buff, size, "b=AS:%d\r\n", c->bit_rate / 1000);
252    }
253
254    sdp_write_media_attributes(buff, size, c, payload_type);
255}
256
257int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size)
258{
259    AVMetadataTag *title = av_metadata_get(ac[0]->metadata, "title", NULL, 0);
260    struct sdp_session_level s;
261    int i, j, port, ttl;
262    char dst[32];
263
264    memset(buff, 0, size);
265    memset(&s, 0, sizeof(struct sdp_session_level));
266    s.user = "-";
267    s.src_addr = "127.0.0.1";    /* FIXME: Properly set this */
268    s.name = title ? title->value : "No Name";
269
270    port = 0;
271    ttl = 0;
272    if (n_files == 1) {
273        port = sdp_get_address(dst, sizeof(dst), &ttl, ac[0]->filename);
274        if (port > 0) {
275            s.dst_addr = dst;
276            s.ttl = ttl;
277        }
278    }
279    sdp_write_header(buff, size, &s);
280
281    dst[0] = 0;
282    for (i = 0; i < n_files; i++) {
283        if (n_files != 1) {
284            port = sdp_get_address(dst, sizeof(dst), &ttl, ac[i]->filename);
285        }
286        for (j = 0; j < ac[i]->nb_streams; j++) {
287            sdp_write_media(buff, size,
288                                  ac[i]->streams[j]->codec, dst[0] ? dst : NULL,
289                                  (port > 0) ? port + j * 2 : 0, ttl);
290            if (port <= 0) {
291                av_strlcatf(buff, size,
292                                   "a=control:streamid=%d\r\n", i + j);
293            }
294        }
295    }
296
297    return 0;
298}
299#else
300int avf_sdp_create(AVFormatContext *ac[], int n_files, char *buff, int size)
301{
302    return AVERROR(ENOSYS);
303}
304#endif
305