FFmpeg
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/mem.h"
24 #include "libavutil/parseutils.h"
25 #include "libavutil/random_seed.h"
26 #include "libavutil/avstring.h"
27 #include "libavutil/dict.h"
28 #include "libavutil/intreadwrite.h"
29 #include "libavutil/time.h"
30 #include "internal.h"
31 #include "mux.h"
32 #include "network.h"
33 #include "os_support.h"
34 #include "rtpenc_chain.h"
35 #include "url.h"
36 
37 struct SAPState {
38  uint8_t *ann;
39  int ann_size;
40  URLContext *ann_fd;
41  int64_t last_time;
42 };
43 
44 static int sap_write_close(AVFormatContext *s)
45 {
46  struct SAPState *sap = s->priv_data;
47  int i;
48 
49  for (i = 0; i < s->nb_streams; i++) {
50  AVFormatContext *rtpctx = s->streams[i]->priv_data;
51  if (!rtpctx)
52  continue;
53  av_write_trailer(rtpctx);
54  avio_closep(&rtpctx->pb);
55  avformat_free_context(rtpctx);
56  s->streams[i]->priv_data = NULL;
57  }
58 
59  if (sap->last_time && sap->ann && sap->ann_fd) {
60  sap->ann[0] |= 4; /* Session deletion*/
61  ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
62  }
63 
64  av_freep(&sap->ann);
65  ffurl_closep(&sap->ann_fd);
66  ff_network_close();
67  return 0;
68 }
69 
70 static int sap_write_header(AVFormatContext *s)
71 {
72  struct SAPState *sap = s->priv_data;
73  char host[1024], path[1024], url[1024], announce_addr[50] = "";
74  char *option_list;
75  int port = 9875, base_port = 5004, i, pos = 0, same_port = 0, ttl = 255;
76  AVFormatContext **contexts = NULL;
77  int ret = 0;
78  struct sockaddr_storage localaddr;
79  socklen_t addrlen = sizeof(localaddr);
80  int udp_fd;
81  AVDictionaryEntry* title = av_dict_get(s->metadata, "title", NULL, 0);
82 
83  if (!ff_network_init())
84  return AVERROR(EIO);
85 
86  /* extract hostname and port */
87  av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &base_port,
88  path, sizeof(path), s->url);
89  if (base_port < 0)
90  base_port = 5004;
91 
92  /* search for options */
93  option_list = strrchr(path, '?');
94  if (option_list) {
95  char buf[50];
96  if (av_find_info_tag(buf, sizeof(buf), "announce_port", option_list)) {
97  port = strtol(buf, NULL, 10);
98  }
99  if (av_find_info_tag(buf, sizeof(buf), "same_port", option_list)) {
100  same_port = strtol(buf, NULL, 10);
101  }
102  if (av_find_info_tag(buf, sizeof(buf), "ttl", option_list)) {
103  ttl = strtol(buf, NULL, 10);
104  }
105  if (av_find_info_tag(buf, sizeof(buf), "announce_addr", option_list)) {
106  av_strlcpy(announce_addr, buf, sizeof(announce_addr));
107  }
108  }
109 
110  if (!announce_addr[0]) {
111  struct addrinfo hints = { 0 }, *ai = NULL;
112  hints.ai_family = AF_UNSPEC;
113  if (getaddrinfo(host, NULL, &hints, &ai)) {
114  av_log(s, AV_LOG_ERROR, "Unable to resolve %s\n", host);
115  ret = AVERROR(EIO);
116  goto fail;
117  }
118  if (ai->ai_family == AF_INET) {
119  /* Also known as sap.mcast.net */
120  av_strlcpy(announce_addr, "224.2.127.254", sizeof(announce_addr));
121 #if HAVE_STRUCT_SOCKADDR_IN6
122  } else if (ai->ai_family == AF_INET6) {
123  /* With IPv6, you can use the same destination in many different
124  * multicast subnets, to choose how far you want it routed.
125  * This one is intended to be routed globally. */
126  av_strlcpy(announce_addr, "ff0e::2:7ffe", sizeof(announce_addr));
127 #endif
128  } else {
129  freeaddrinfo(ai);
130  av_log(s, AV_LOG_ERROR, "Host %s resolved to unsupported "
131  "address family\n", host);
132  ret = AVERROR(EIO);
133  goto fail;
134  }
135  freeaddrinfo(ai);
136  }
137 
138  contexts = av_calloc(s->nb_streams, sizeof(*contexts));
139  if (!contexts) {
140  ret = AVERROR(ENOMEM);
141  goto fail;
142  }
143 
144  if (s->start_time_realtime == 0 || s->start_time_realtime == AV_NOPTS_VALUE)
145  s->start_time_realtime = av_gettime();
146  for (i = 0; i < s->nb_streams; i++) {
147  URLContext *fd;
148  char *new_url;
149 
150  ff_url_join(url, sizeof(url), "rtp", NULL, host, base_port,
151  "?ttl=%d", ttl);
152  if (!same_port)
153  base_port += 2;
154  ret = ffurl_open_whitelist(&fd, url, AVIO_FLAG_WRITE,
155  &s->interrupt_callback, NULL,
156  s->protocol_whitelist, s->protocol_blacklist, NULL);
157  if (ret) {
158  ret = AVERROR(EIO);
159  goto fail;
160  }
161  ret = ff_rtp_chain_mux_open(&contexts[i], s, s->streams[i], fd, 0, i);
162  if (ret < 0)
163  goto fail;
164  s->streams[i]->priv_data = contexts[i];
165  s->streams[i]->time_base = contexts[i]->streams[0]->time_base;
166  new_url = av_strdup(url);
167  if (!new_url) {
168  ret = AVERROR(ENOMEM);
169  goto fail;
170  }
171  ff_format_set_url(contexts[i], new_url);
172  }
173 
174  if (s->nb_streams > 0 && title)
175  av_dict_set(&contexts[0]->metadata, "title", title->value, 0);
176 
177  ff_url_join(url, sizeof(url), "udp", NULL, announce_addr, port,
178  "?ttl=%d&connect=1", ttl);
179  ret = ffurl_open_whitelist(&sap->ann_fd, url, AVIO_FLAG_WRITE,
180  &s->interrupt_callback, NULL,
181  s->protocol_whitelist, s->protocol_blacklist, NULL);
182  if (ret) {
183  ret = AVERROR(EIO);
184  goto fail;
185  }
186 
187  udp_fd = ffurl_get_file_handle(sap->ann_fd);
188  if (getsockname(udp_fd, (struct sockaddr*) &localaddr, &addrlen)) {
189  ret = AVERROR(EIO);
190  goto fail;
191  }
192  if (localaddr.ss_family != AF_INET
193 #if HAVE_STRUCT_SOCKADDR_IN6
194  && localaddr.ss_family != AF_INET6
195 #endif
196  ) {
197  av_log(s, AV_LOG_ERROR, "Unsupported protocol family\n");
198  ret = AVERROR(EIO);
199  goto fail;
200  }
201  sap->ann_size = 8192;
202  sap->ann = av_mallocz(sap->ann_size);
203  if (!sap->ann) {
204  ret = AVERROR(EIO);
205  goto fail;
206  }
207  sap->ann[pos] = (1 << 5);
208 #if HAVE_STRUCT_SOCKADDR_IN6
209  if (localaddr.ss_family == AF_INET6)
210  sap->ann[pos] |= 0x10;
211 #endif
212  pos++;
213  sap->ann[pos++] = 0; /* Authentication length */
214  AV_WB16(&sap->ann[pos], av_get_random_seed());
215  pos += 2;
216  if (localaddr.ss_family == AF_INET) {
217  memcpy(&sap->ann[pos], &((struct sockaddr_in*)&localaddr)->sin_addr,
218  sizeof(struct in_addr));
219  pos += sizeof(struct in_addr);
220 #if HAVE_STRUCT_SOCKADDR_IN6
221  } else {
222  memcpy(&sap->ann[pos], &((struct sockaddr_in6*)&localaddr)->sin6_addr,
223  sizeof(struct in6_addr));
224  pos += sizeof(struct in6_addr);
225 #endif
226  }
227 
228  av_strlcpy(&sap->ann[pos], "application/sdp", sap->ann_size - pos);
229  pos += strlen(&sap->ann[pos]) + 1;
230 
231  if (av_sdp_create(contexts, s->nb_streams, &sap->ann[pos],
232  sap->ann_size - pos)) {
233  ret = AVERROR_INVALIDDATA;
234  goto fail;
235  }
236  av_freep(&contexts);
237  av_log(s, AV_LOG_VERBOSE, "SDP:\n%s\n", &sap->ann[pos]);
238  pos += strlen(&sap->ann[pos]);
239  sap->ann_size = pos;
240 
241  if (sap->ann_size > sap->ann_fd->max_packet_size) {
242  av_log(s, AV_LOG_ERROR, "Announcement too large to send in one "
243  "packet\n");
244  goto fail;
245  }
246 
247  return 0;
248 
249 fail:
250  av_free(contexts);
251  sap_write_close(s);
252  return ret;
253 }
254 
255 static int sap_write_packet(AVFormatContext *s, AVPacket *pkt)
256 {
257  AVFormatContext *rtpctx;
258  struct SAPState *sap = s->priv_data;
259  int64_t now = av_gettime_relative();
260 
261  if (!sap->last_time || now - sap->last_time > 5000000) {
262  int ret = ffurl_write(sap->ann_fd, sap->ann, sap->ann_size);
263  /* Don't abort even if we get "Destination unreachable" */
264  if (ret < 0 && ret != AVERROR(ECONNREFUSED))
265  return ret;
266  sap->last_time = now;
267  }
268  rtpctx = s->streams[pkt->stream_index]->priv_data;
269  return ff_write_chained(rtpctx, 0, pkt, s, 0);
270 }
271 
272 const FFOutputFormat ff_sap_muxer = {
273  .p.name = "sap",
274  .p.long_name = NULL_IF_CONFIG_SMALL("SAP output"),
275  .priv_data_size = sizeof(struct SAPState),
276  .p.audio_codec = AV_CODEC_ID_AAC,
277  .p.video_codec = AV_CODEC_ID_MPEG4,
278  .write_header = sap_write_header,
279  .write_packet = sap_write_packet,
280  .write_trailer = sap_write_close,
281  .p.flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER,
282 };
av_gettime_relative
int64_t av_gettime_relative(void)
Get the current time in microseconds since some unspecified starting point.
Definition: time.c:56
AVOutputFormat::name
const char * name
Definition: avformat.h:510
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
av_find_info_tag
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:753
SAPState::ann_fd
URLContext * ann_fd
Definition: sapdec.c:38
sap_write_packet
static int sap_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: sapenc.c:255
ffurl_write
static int ffurl_write(URLContext *h, const uint8_t *buf, int size)
Write size bytes from buf to the resource accessed by h.
Definition: url.h:202
AV_CODEC_ID_MPEG4
@ AV_CODEC_ID_MPEG4
Definition: codec_id.h:64
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1323
URLContext::max_packet_size
int max_packet_size
if non zero, the stream is packetized with this max packet size
Definition: url.h:41
SAPState
Definition: sapdec.c:37
AV_LOG_VERBOSE
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:196
SAPState::ann
uint8_t * ann
Definition: sapenc.c:38
ff_sap_muxer
const FFOutputFormat ff_sap_muxer
Definition: sapenc.c:272
ff_network_close
void ff_network_close(void)
Definition: network.c:116
os_support.h
sockaddr_storage
Definition: network.h:111
ff_network_init
int ff_network_init(void)
Definition: network.c:58
FFOutputFormat::p
AVOutputFormat p
The public AVOutputFormat.
Definition: mux.h:65
av_get_random_seed
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:167
freeaddrinfo
#define freeaddrinfo
Definition: network.h:218
fail
#define fail()
Definition: checkasm.h:179
rtpenc_chain.h
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_dict_get
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:62
ffurl_open_whitelist
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:362
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
ff_url_join
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:40
AVIO_FLAG_WRITE
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:618
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:782
NULL
#define NULL
Definition: coverity.c:32
AV_WB16
#define AV_WB16(p, v)
Definition: intreadwrite.h:403
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1297
parseutils.h
FFOutputFormat
Definition: mux.h:61
time.h
AV_CODEC_ID_AAC
@ AV_CODEC_ID_AAC
Definition: codec_id.h:442
addrinfo::ai_family
int ai_family
Definition: network.h:139
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:94
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
AVFMT_NOFILE
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:468
av_sdp_create
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size)
Generate an SDP for an RTP session.
Definition: sdp.c:912
getaddrinfo
#define getaddrinfo
Definition: network.h:217
av_write_trailer
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1295
URLContext
Definition: url.h:35
AVFMT_GLOBALHEADER
#define AVFMT_GLOBALHEADER
Format wants global header.
Definition: avformat.h:478
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
av_url_split
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:359
url.h
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:256
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:264
SAPState::ann_size
int ann_size
Definition: sapenc.c:39
SAPState::last_time
int64_t last_time
Definition: sapenc.c:41
ffurl_closep
int ffurl_closep(URLContext **hh)
Close the resource accessed by the URLContext h, and free the memory used by it.
Definition: avio.c:588
ret
ret
Definition: filter_design.txt:187
pos
unsigned int pos
Definition: spdifenc.c:414
avformat.h
ff_rtp_chain_mux_open
int ff_rtp_chain_mux_open(AVFormatContext **out, AVFormatContext *s, AVStream *st, URLContext *handle, int packet_size, int idx)
Definition: rtpenc_chain.c:29
dict.h
network.h
random_seed.h
sap_write_header
static int sap_write_header(AVFormatContext *s)
Definition: sapenc.c:70
avformat_free_context
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: avformat.c:141
AVPacket::stream_index
int stream_index
Definition: packet.h:526
av_gettime
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:272
mem.h
sap_write_close
static int sap_write_close(AVFormatContext *s)
Definition: sapenc.c:44
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AVDictionaryEntry
Definition: dict.h:89
AVPacket
This structure stores compressed data.
Definition: packet.h:501
avio_closep
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: avio.c:649
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
av_dict_set
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:88
av_strlcpy
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:85
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AVDictionaryEntry::value
char * value
Definition: dict.h:91
avstring.h
addrinfo
Definition: network.h:137
ff_format_set_url
void ff_format_set_url(AVFormatContext *s, char *url)
Set AVFormatContext url field to the provided pointer.
Definition: avformat.c:937
ffurl_get_file_handle
int ffurl_get_file_handle(URLContext *h)
Return the file descriptor associated with this URL.
Definition: avio.c:814
mux.h
ff_write_chained
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:1394
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