Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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_close(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(sizeof(AVFormatContext*) * s->nb_streams);
138  if (!contexts) {
139  ret = AVERROR(ENOMEM);
140  goto fail;
141  }
142 
144  for (i = 0; i < s->nb_streams; i++) {
145  URLContext *fd;
146 
147  ff_url_join(url, sizeof(url), "rtp", NULL, host, base_port,
148  "?ttl=%d", ttl);
149  if (!same_port)
150  base_port += 2;
151  ret = ffurl_open(&fd, url, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
152  if (ret) {
153  ret = AVERROR(EIO);
154  goto fail;
155  }
156  ret = ff_rtp_chain_mux_open(&contexts[i], s, s->streams[i], fd, 0, i);
157  if (ret < 0)
158  goto fail;
159  s->streams[i]->priv_data = contexts[i];
160  s->streams[i]->time_base = contexts[i]->streams[0]->time_base;
161  av_strlcpy(contexts[i]->filename, url, sizeof(contexts[i]->filename));
162  }
163 
164  if (s->nb_streams > 0 && title)
165  av_dict_set(&contexts[0]->metadata, "title", title->value, 0);
166 
167  ff_url_join(url, sizeof(url), "udp", NULL, announce_addr, port,
168  "?ttl=%d&connect=1", ttl);
169  ret = ffurl_open(&sap->ann_fd, url, AVIO_FLAG_WRITE,
170  &s->interrupt_callback, NULL);
171  if (ret) {
172  ret = AVERROR(EIO);
173  goto fail;
174  }
175 
176  udp_fd = ffurl_get_file_handle(sap->ann_fd);
177  if (getsockname(udp_fd, (struct sockaddr*) &localaddr, &addrlen)) {
178  ret = AVERROR(EIO);
179  goto fail;
180  }
181  if (localaddr.ss_family != AF_INET
183  && localaddr.ss_family != AF_INET6
184 #endif
185  ) {
186  av_log(s, AV_LOG_ERROR, "Unsupported protocol family\n");
187  ret = AVERROR(EIO);
188  goto fail;
189  }
190  sap->ann_size = 8192;
191  sap->ann = av_mallocz(sap->ann_size);
192  if (!sap->ann) {
193  ret = AVERROR(EIO);
194  goto fail;
195  }
196  sap->ann[pos] = (1 << 5);
197 #if HAVE_STRUCT_SOCKADDR_IN6
198  if (localaddr.ss_family == AF_INET6)
199  sap->ann[pos] |= 0x10;
200 #endif
201  pos++;
202  sap->ann[pos++] = 0; /* Authentication length */
203  AV_WB16(&sap->ann[pos], av_get_random_seed());
204  pos += 2;
205  if (localaddr.ss_family == AF_INET) {
206  memcpy(&sap->ann[pos], &((struct sockaddr_in*)&localaddr)->sin_addr,
207  sizeof(struct in_addr));
208  pos += sizeof(struct in_addr);
209 #if HAVE_STRUCT_SOCKADDR_IN6
210  } else {
211  memcpy(&sap->ann[pos], &((struct sockaddr_in6*)&localaddr)->sin6_addr,
212  sizeof(struct in6_addr));
213  pos += sizeof(struct in6_addr);
214 #endif
215  }
216 
217  av_strlcpy(&sap->ann[pos], "application/sdp", sap->ann_size - pos);
218  pos += strlen(&sap->ann[pos]) + 1;
219 
220  if (av_sdp_create(contexts, s->nb_streams, &sap->ann[pos],
221  sap->ann_size - pos)) {
222  ret = AVERROR_INVALIDDATA;
223  goto fail;
224  }
225  av_freep(&contexts);
226  av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", &sap->ann[pos]);
227  pos += strlen(&sap->ann[pos]);
228  sap->ann_size = pos;
229 
230  if (sap->ann_size > sap->ann_fd->max_packet_size) {
231  av_log(s, AV_LOG_ERROR, "Announcement too large to send in one "
232  "packet\n");
233  goto fail;
234  }
235 
236  return 0;
237 
238 fail:
239  av_free(contexts);
240  sap_write_close(s);
241  return ret;
242 }
243 
245 {
246  AVFormatContext *rtpctx;
247  struct SAPState *sap = s->priv_data;
248  int64_t now = av_gettime();
249 
250  if (!sap->last_time || now - sap->last_time > 5000000) {
251  int ret = ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
252  /* Don't abort even if we get "Destination unreachable" */
253  if (ret < 0 && ret != AVERROR(ECONNREFUSED))
254  return ret;
255  sap->last_time = now;
256  }
257  rtpctx = s->streams[pkt->stream_index]->priv_data;
258  return ff_write_chained(rtpctx, 0, pkt, s);
259 }
260 
262  .name = "sap",
263  .long_name = NULL_IF_CONFIG_SMALL("SAP output"),
264  .priv_data_size = sizeof(struct SAPState),
265  .audio_codec = AV_CODEC_ID_AAC,
266  .video_codec = AV_CODEC_ID_MPEG4,
267  .write_header = sap_write_header,
268  .write_packet = sap_write_packet,
269  .write_trailer = sap_write_close,
270  .flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER,
271 };
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:2713
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
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:1138
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1163
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:276
int64_t last_time
Definition: sapenc.c:39
#define HAVE_STRUCT_SOCKADDR_IN6
Definition: config.h:273
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:293
void ff_network_close(void)
Definition: network.c:150
void * priv_data
Definition: avformat.h:719
#define freeaddrinfo
Definition: network.h:183
AVOutputFormat ff_sap_muxer
Definition: sapenc.c:261
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
Format I/O context.
Definition: avformat.h:922
static int sap_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: sapenc.c:244
Public dictionary API.
uint8_t
int ff_network_init(void)
Definition: network.c:123
miscellaneous OS support macros and functions.
uint16_t ss_family
Definition: network.h:93
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:990
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:38
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:139
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
Definition: sdp.c:689
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:606
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1130
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
#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:150
int avio_close(AVIOContext *s)
Close the resource accessed by the AVIOContext s and free it.
Definition: aviobuf.c:800
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
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:81
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:978
char filename[1024]
input or output filename
Definition: avformat.h:998
URLContext * ann_fd
Definition: sapdec.c:36
uint8_t * ann
Definition: sapenc.c:36
#define AVFMT_GLOBALHEADER
Format wants global header.
Definition: avformat.h:415
const char * name
Definition: avformat.h:446
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:352
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:37
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
NULL
Definition: eval.c:55
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:964
Definition: url.h:41
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:68
#define AV_WB16(p, d)
Definition: intreadwrite.h:213
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: utils.c:2445
misc parsing utilities
int ffurl_close(URLContext *h)
Close the resource accessed by the URLContext h, and free the memory used by it.
Definition: avio.c:297
#define getaddrinfo
Definition: network.h:182
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:29
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:409
int ffurl_open(URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Create an URLContext for accessing to the resource indicated by url, and open it. ...
Definition: avio.c:211
int ff_write_chained(AVFormatContext *dst, int dst_stream, AVPacket *pkt, AVFormatContext *src)
Write a packet to another muxer than the one the user originally intended.
Definition: mux.c:622
char * value
Definition: dict.h:76
void * priv_data
Format private data.
Definition: avformat.h:950
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:583
int max_packet_size
if non zero, the stream is packetized with this max packet size
Definition: url.h:47
unbuffered private I/O API
uint32_t av_get_random_seed(void)
Get random data.
Definition: random_seed.c:95
int stream_index
Definition: avcodec.h:975
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:741
This structure stores compressed data.
Definition: avcodec.h:950
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:205
int ai_family
Definition: network.h:104