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sapenc.c
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1 /*
2  * Session Announcement Protocol (RFC 2974) muxer
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/parseutils.h"
24 #include "libavutil/random_seed.h"
25 #include "libavutil/avstring.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/intreadwrite.h"
28 #include "libavutil/time.h"
29 #include "internal.h"
30 #include "network.h"
31 #include "os_support.h"
32 #include "rtpenc_chain.h"
33 #include "url.h"
34 
35 struct SAPState {
37  int ann_size;
39  int64_t last_time;
40 };
41 
43 {
44  struct SAPState *sap = s->priv_data;
45  int i;
46 
47  for (i = 0; i < s->nb_streams; i++) {
48  AVFormatContext *rtpctx = s->streams[i]->priv_data;
49  if (!rtpctx)
50  continue;
51  av_write_trailer(rtpctx);
52  avio_closep(&rtpctx->pb);
53  avformat_free_context(rtpctx);
54  s->streams[i]->priv_data = NULL;
55  }
56 
57  if (sap->last_time && sap->ann && sap->ann_fd) {
58  sap->ann[0] |= 4; /* Session deletion*/
59  ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
60  }
61 
62  av_freep(&sap->ann);
63  if (sap->ann_fd)
64  ffurl_close(sap->ann_fd);
66  return 0;
67 }
68 
70 {
71  struct SAPState *sap = s->priv_data;
72  char host[1024], path[1024], url[1024], announce_addr[50] = "";
73  char *option_list;
74  int port = 9875, base_port = 5004, i, pos = 0, same_port = 0, ttl = 255;
75  AVFormatContext **contexts = NULL;
76  int ret = 0;
77  struct sockaddr_storage localaddr;
78  socklen_t addrlen = sizeof(localaddr);
79  int udp_fd;
80  AVDictionaryEntry* title = av_dict_get(s->metadata, "title", NULL, 0);
81 
82  if (!ff_network_init())
83  return AVERROR(EIO);
84 
85  /* extract hostname and port */
86  av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &base_port,
87  path, sizeof(path), s->filename);
88  if (base_port < 0)
89  base_port = 5004;
90 
91  /* search for options */
92  option_list = strrchr(path, '?');
93  if (option_list) {
94  char buf[50];
95  if (av_find_info_tag(buf, sizeof(buf), "announce_port", option_list)) {
96  port = strtol(buf, NULL, 10);
97  }
98  if (av_find_info_tag(buf, sizeof(buf), "same_port", option_list)) {
99  same_port = strtol(buf, NULL, 10);
100  }
101  if (av_find_info_tag(buf, sizeof(buf), "ttl", option_list)) {
102  ttl = strtol(buf, NULL, 10);
103  }
104  if (av_find_info_tag(buf, sizeof(buf), "announce_addr", option_list)) {
105  av_strlcpy(announce_addr, buf, sizeof(announce_addr));
106  }
107  }
108 
109  if (!announce_addr[0]) {
110  struct addrinfo hints = { 0 }, *ai = NULL;
111  hints.ai_family = AF_UNSPEC;
112  if (getaddrinfo(host, NULL, &hints, &ai)) {
113  av_log(s, AV_LOG_ERROR, "Unable to resolve %s\n", host);
114  ret = AVERROR(EIO);
115  goto fail;
116  }
117  if (ai->ai_family == AF_INET) {
118  /* Also known as sap.mcast.net */
119  av_strlcpy(announce_addr, "224.2.127.254", sizeof(announce_addr));
120 #if HAVE_STRUCT_SOCKADDR_IN6
121  } else if (ai->ai_family == AF_INET6) {
122  /* With IPv6, you can use the same destination in many different
123  * multicast subnets, to choose how far you want it routed.
124  * This one is intended to be routed globally. */
125  av_strlcpy(announce_addr, "ff0e::2:7ffe", sizeof(announce_addr));
126 #endif
127  } else {
128  freeaddrinfo(ai);
129  av_log(s, AV_LOG_ERROR, "Host %s resolved to unsupported "
130  "address family\n", host);
131  ret = AVERROR(EIO);
132  goto fail;
133  }
134  freeaddrinfo(ai);
135  }
136 
137  contexts = av_mallocz_array(s->nb_streams, sizeof(AVFormatContext*));
138  if (!contexts) {
139  ret = AVERROR(ENOMEM);
140  goto fail;
141  }
142 
145  for (i = 0; i < s->nb_streams; i++) {
146  URLContext *fd;
147 
148  ff_url_join(url, sizeof(url), "rtp", NULL, host, base_port,
149  "?ttl=%d", ttl);
150  if (!same_port)
151  base_port += 2;
152  ret = ffurl_open_whitelist(&fd, url, AVIO_FLAG_WRITE,
155  if (ret) {
156  ret = AVERROR(EIO);
157  goto fail;
158  }
159  ret = ff_rtp_chain_mux_open(&contexts[i], s, s->streams[i], fd, 0, i);
160  if (ret < 0)
161  goto fail;
162  s->streams[i]->priv_data = contexts[i];
163  s->streams[i]->time_base = contexts[i]->streams[0]->time_base;
164  av_strlcpy(contexts[i]->filename, url, sizeof(contexts[i]->filename));
165  }
166 
167  if (s->nb_streams > 0 && title)
168  av_dict_set(&contexts[0]->metadata, "title", title->value, 0);
169 
170  ff_url_join(url, sizeof(url), "udp", NULL, announce_addr, port,
171  "?ttl=%d&connect=1", ttl);
172  ret = ffurl_open_whitelist(&sap->ann_fd, url, AVIO_FLAG_WRITE,
175  if (ret) {
176  ret = AVERROR(EIO);
177  goto fail;
178  }
179 
180  udp_fd = ffurl_get_file_handle(sap->ann_fd);
181  if (getsockname(udp_fd, (struct sockaddr*) &localaddr, &addrlen)) {
182  ret = AVERROR(EIO);
183  goto fail;
184  }
185  if (localaddr.ss_family != AF_INET
186 #if HAVE_STRUCT_SOCKADDR_IN6
187  && localaddr.ss_family != AF_INET6
188 #endif
189  ) {
190  av_log(s, AV_LOG_ERROR, "Unsupported protocol family\n");
191  ret = AVERROR(EIO);
192  goto fail;
193  }
194  sap->ann_size = 8192;
195  sap->ann = av_mallocz(sap->ann_size);
196  if (!sap->ann) {
197  ret = AVERROR(EIO);
198  goto fail;
199  }
200  sap->ann[pos] = (1 << 5);
201 #if HAVE_STRUCT_SOCKADDR_IN6
202  if (localaddr.ss_family == AF_INET6)
203  sap->ann[pos] |= 0x10;
204 #endif
205  pos++;
206  sap->ann[pos++] = 0; /* Authentication length */
207  AV_WB16(&sap->ann[pos], av_get_random_seed());
208  pos += 2;
209  if (localaddr.ss_family == AF_INET) {
210  memcpy(&sap->ann[pos], &((struct sockaddr_in*)&localaddr)->sin_addr,
211  sizeof(struct in_addr));
212  pos += sizeof(struct in_addr);
213 #if HAVE_STRUCT_SOCKADDR_IN6
214  } else {
215  memcpy(&sap->ann[pos], &((struct sockaddr_in6*)&localaddr)->sin6_addr,
216  sizeof(struct in6_addr));
217  pos += sizeof(struct in6_addr);
218 #endif
219  }
220 
221  av_strlcpy(&sap->ann[pos], "application/sdp", sap->ann_size - pos);
222  pos += strlen(&sap->ann[pos]) + 1;
223 
224  if (av_sdp_create(contexts, s->nb_streams, &sap->ann[pos],
225  sap->ann_size - pos)) {
226  ret = AVERROR_INVALIDDATA;
227  goto fail;
228  }
229  av_freep(&contexts);
230  av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", &sap->ann[pos]);
231  pos += strlen(&sap->ann[pos]);
232  sap->ann_size = pos;
233 
234  if (sap->ann_size > sap->ann_fd->max_packet_size) {
235  av_log(s, AV_LOG_ERROR, "Announcement too large to send in one "
236  "packet\n");
237  goto fail;
238  }
239 
240  return 0;
241 
242 fail:
243  av_free(contexts);
244  sap_write_close(s);
245  return ret;
246 }
247 
249 {
250  AVFormatContext *rtpctx;
251  struct SAPState *sap = s->priv_data;
252  int64_t now = av_gettime_relative();
253 
254  if (!sap->last_time || now - sap->last_time > 5000000) {
255  int ret = ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
256  /* Don't abort even if we get "Destination unreachable" */
257  if (ret < 0 && ret != AVERROR(ECONNREFUSED))
258  return ret;
259  sap->last_time = now;
260  }
261  rtpctx = s->streams[pkt->stream_index]->priv_data;
262  return ff_write_chained(rtpctx, 0, pkt, s, 0);
263 }
264 
266  .name = "sap",
267  .long_name = NULL_IF_CONFIG_SMALL("SAP output"),
268  .priv_data_size = sizeof(struct SAPState),
269  .audio_codec = AV_CODEC_ID_AAC,
270  .video_codec = AV_CODEC_ID_MPEG4,
271  .write_header = sap_write_header,
272  .write_packet = sap_write_packet,
273  .write_trailer = sap_write_close,
274  .flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER,
275 };
void av_url_split(char *proto, int proto_size, char *authorization, int authorization_size, char *hostname, int hostname_size, int *port_ptr, char *path, int path_size, const char *url)
Split a URL string into components.
Definition: utils.c:4384
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t start_time_realtime
Start time of the stream in real world time, in microseconds since the Unix epoch (00:00 1st January ...
Definition: avformat.h:1554
int ffurl_open_whitelist(URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options, const char *whitelist, const char *blacklist, URLContext *parent)
Create an URLContext for accessing to the resource indicated by url, and open it. ...
Definition: avio.c:309
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1579
int ffurl_write(URLContext *h, const unsigned char *buf, int size)
Write size bytes from buf to the resource accessed by h.
Definition: avio.c:421
int ff_write_chained(AVFormatContext *dst, int dst_stream, AVPacket *pkt, AVFormatContext *src, int interleave)
Write a packet to another muxer than the one the user originally intended.
Definition: mux.c:1276
int64_t last_time
Definition: sapenc.c:39
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:607
void ff_network_close(void)
Definition: network.c:102
void * priv_data
Definition: avformat.h:893
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:252
#define freeaddrinfo
Definition: network.h:208
static AVPacket pkt
AVOutputFormat ff_sap_muxer
Definition: sapenc.c:265
Format I/O context.
Definition: avformat.h:1327
static int sap_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: sapenc.c:248
Public dictionary API.
uint8_t
int ff_network_init(void)
Definition: network.c:55
miscellaneous OS support macros and functions.
uint16_t ss_family
Definition: network.h:106
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1395
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
char * protocol_whitelist
',' separated list of allowed protocols.
Definition: avformat.h:1863
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
Definition: sdp.c:827
int av_find_info_tag(char *arg, int arg_size, const char *tag1, const char *info)
Attempt to find a specific tag in a URL.
Definition: parseutils.c:705
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1541
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
static void * av_mallocz_array(size_t nmemb, size_t size)
Definition: mem.h:226
size_t av_strlcpy(char *dst, const char *src, size_t size)
Copy the string src to dst, but no more than size - 1 bytes, and null-terminate dst.
Definition: avstring.c:83
#define fail()
Definition: checkasm.h:82
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1383
char filename[1024]
input or output filename
Definition: avformat.h:1403
URLContext * ann_fd
Definition: sapdec.c:37
uint8_t * ann
Definition: sapenc.c:36
#define AVFMT_GLOBALHEADER
Format wants global header.
Definition: avformat.h:485
const char * name
Definition: avformat.h:524
static int sap_write_close(AVFormatContext *s)
Definition: sapenc.c:42
int ffurl_get_file_handle(URLContext *h)
Return the file descriptor associated with this URL.
Definition: avio.c:626
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
int ff_url_join(char *str, int size, const char *proto, const char *authorization, const char *hostname, int port, const char *fmt,...)
Definition: url.c:36
static int sap_write_header(AVFormatContext *s)
Definition: sapenc.c:69
int ann_size
Definition: sapenc.c:37
AVIOContext * pb
I/O context.
Definition: avformat.h:1369
void * buf
Definition: avisynth_c.h:690
Definition: url.h:38
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: utils.c:4073
misc parsing utilities
int64_t av_gettime_relative(void)
Get the current time in microseconds since some unspecified starting point.
Definition: time.c:56
int ffurl_close(URLContext *h)
Definition: avio.c:467
#define getaddrinfo
Definition: network.h:207
Main libavformat public API header.
int ff_rtp_chain_mux_open(AVFormatContext **out, AVFormatContext *s, AVStream *st, URLContext *handle, int packet_size, int idx)
Definition: rtpenc_chain.c:28
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:478
#define av_free(p)
char * value
Definition: dict.h:87
void * priv_data
Format private data.
Definition: avformat.h:1355
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1209
char * protocol_blacklist
',' separated list of disallowed protocols.
Definition: avformat.h:1898
int max_packet_size
if non zero, the stream is packetized with this max packet size
Definition: url.h:44
#define av_freep(p)
unbuffered private I/O API
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:114
int stream_index
Definition: avcodec.h:1592
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:915
This structure stores compressed data.
Definition: avcodec.h:1567
int avio_closep(AVIOContext **s)
Close the resource accessed by the AVIOContext *s, free it and set the pointer pointing to it to NULL...
Definition: aviobuf.c:1092
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:242
int ai_family
Definition: network.h:129