FFmpeg
tcp.c
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1 /*
2  * TCP protocol
3  * Copyright (c) 2002 Fabrice Bellard
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 #include "avformat.h"
22 #include "libavutil/avassert.h"
23 #include "libavutil/mem.h"
24 #include "libavutil/parseutils.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/time.h"
27 
28 #include "network.h"
29 #include "os_support.h"
30 #include "url.h"
31 #if HAVE_POLL_H
32 #include <poll.h>
33 #endif
34 
35 typedef struct TCPContext {
36  const AVClass *class;
37  int fd;
38  int listen;
39  char *local_port;
40  char *local_addr;
47 #if !HAVE_WINSOCK2_H
48  int tcp_mss;
49 #endif /* !HAVE_WINSOCK2_H */
50 } TCPContext;
51 
52 #define OFFSET(x) offsetof(TCPContext, x)
53 #define D AV_OPT_FLAG_DECODING_PARAM
54 #define E AV_OPT_FLAG_ENCODING_PARAM
55 static const AVOption options[] = {
56  { "listen", "Listen for incoming connections", OFFSET(listen), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 2, .flags = D|E },
57  { "local_port", "Local port", OFFSET(local_port), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, .flags = D|E },
58  { "local_addr", "Local address", OFFSET(local_addr), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, .flags = D|E },
59  { "timeout", "set timeout (in microseconds) of socket I/O operations", OFFSET(rw_timeout), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
60  { "listen_timeout", "Connection awaiting timeout (in milliseconds)", OFFSET(listen_timeout), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
61  { "send_buffer_size", "Socket send buffer size (in bytes)", OFFSET(send_buffer_size), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
62  { "recv_buffer_size", "Socket receive buffer size (in bytes)", OFFSET(recv_buffer_size), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
63  { "tcp_nodelay", "Use TCP_NODELAY to disable nagle's algorithm", OFFSET(tcp_nodelay), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, .flags = D|E },
64 #if !HAVE_WINSOCK2_H
65  { "tcp_mss", "Maximum segment size for outgoing TCP packets", OFFSET(tcp_mss), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
66 #endif /* !HAVE_WINSOCK2_H */
67  { NULL }
68 };
69 
70 static const AVClass tcp_class = {
71  .class_name = "tcp",
72  .item_name = av_default_item_name,
73  .option = options,
74  .version = LIBAVUTIL_VERSION_INT,
75 };
76 
77 static int customize_fd(void *ctx, int fd, int family)
78 {
79  TCPContext *s = ctx;
80 
81  if (s->local_addr || s->local_port) {
82  struct addrinfo hints = { 0 }, *ai, *cur_ai;
83  int ret;
84 
85  hints.ai_family = family;
86  hints.ai_socktype = SOCK_STREAM;
87 
88  ret = getaddrinfo(s->local_addr, s->local_port, &hints, &ai);
89  if (ret) {
91  "Failed to getaddrinfo local addr: %s port: %s err: %s\n",
92  s->local_addr, s->local_port, gai_strerror(ret));
93  return ret;
94  }
95 
96  cur_ai = ai;
97  while (cur_ai) {
98  ret = bind(fd, (struct sockaddr *)cur_ai->ai_addr, (int)cur_ai->ai_addrlen);
99  if (ret)
100  cur_ai = cur_ai->ai_next;
101  else
102  break;
103  }
104  freeaddrinfo(ai);
105 
106  if (ret) {
107  ff_log_net_error(ctx, AV_LOG_ERROR, "bind local failed");
108  return ret;
109  }
110  }
111  /* Set the socket's send or receive buffer sizes, if specified.
112  If unspecified or setting fails, system default is used. */
113  if (s->recv_buffer_size > 0) {
114  if (setsockopt (fd, SOL_SOCKET, SO_RCVBUF, &s->recv_buffer_size, sizeof (s->recv_buffer_size))) {
115  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(SO_RCVBUF)");
116  }
117  }
118  if (s->send_buffer_size > 0) {
119  if (setsockopt (fd, SOL_SOCKET, SO_SNDBUF, &s->send_buffer_size, sizeof (s->send_buffer_size))) {
120  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(SO_SNDBUF)");
121  }
122  }
123  if (s->tcp_nodelay > 0) {
124  if (setsockopt (fd, IPPROTO_TCP, TCP_NODELAY, &s->tcp_nodelay, sizeof (s->tcp_nodelay))) {
125  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(TCP_NODELAY)");
126  }
127  }
128 #if !HAVE_WINSOCK2_H
129  if (s->tcp_mss > 0) {
130  if (setsockopt (fd, IPPROTO_TCP, TCP_MAXSEG, &s->tcp_mss, sizeof (s->tcp_mss))) {
131  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(TCP_MAXSEG)");
132  }
133  }
134 #endif /* !HAVE_WINSOCK2_H */
135 
136  return 0;
137 }
138 
139 /* return non zero if error */
140 static int tcp_open(URLContext *h, const char *uri, int flags)
141 {
142  struct addrinfo hints = { 0 }, *ai, *cur_ai;
143  int port, fd = -1;
144  TCPContext *s = h->priv_data;
145  const char *p;
146  char buf[256];
147  int ret;
148  char hostname[1024],proto[1024],path[1024];
149  char portstr[10];
150  s->open_timeout = 5000000;
151 
152  av_url_split(proto, sizeof(proto), NULL, 0, hostname, sizeof(hostname),
153  &port, path, sizeof(path), uri);
154  if (strcmp(proto, "tcp"))
155  return AVERROR(EINVAL);
156  if (port <= 0 || port >= 65536) {
157  av_log(h, AV_LOG_ERROR, "Port missing in uri\n");
158  return AVERROR(EINVAL);
159  }
160  p = strchr(uri, '?');
161  if (p) {
162  if (av_find_info_tag(buf, sizeof(buf), "listen", p)) {
163  char *endptr = NULL;
164  s->listen = strtol(buf, &endptr, 10);
165  /* assume if no digits were found it is a request to enable it */
166  if (buf == endptr)
167  s->listen = 1;
168  }
169  if (av_find_info_tag(buf, sizeof(buf), "local_port", p)) {
170  av_freep(&s->local_port);
171  s->local_port = av_strdup(buf);
172  if (!s->local_port)
173  return AVERROR(ENOMEM);
174  }
175  if (av_find_info_tag(buf, sizeof(buf), "local_addr", p)) {
176  av_freep(&s->local_addr);
177  s->local_addr = av_strdup(buf);
178  if (!s->local_addr)
179  return AVERROR(ENOMEM);
180  }
181  if (av_find_info_tag(buf, sizeof(buf), "timeout", p)) {
182  s->rw_timeout = strtol(buf, NULL, 10);
183  }
184  if (av_find_info_tag(buf, sizeof(buf), "listen_timeout", p)) {
185  s->listen_timeout = strtol(buf, NULL, 10);
186  }
187  if (av_find_info_tag(buf, sizeof(buf), "tcp_nodelay", p)) {
188  s->tcp_nodelay = strtol(buf, NULL, 10);
189  }
190  }
191  if (s->rw_timeout >= 0) {
192  s->open_timeout =
193  h->rw_timeout = s->rw_timeout;
194  }
195  hints.ai_family = AF_UNSPEC;
196  hints.ai_socktype = SOCK_STREAM;
197  snprintf(portstr, sizeof(portstr), "%d", port);
198  if (s->listen)
199  hints.ai_flags |= AI_PASSIVE;
200  if (!hostname[0])
201  ret = getaddrinfo(NULL, portstr, &hints, &ai);
202  else
203  ret = getaddrinfo(hostname, portstr, &hints, &ai);
204  if (ret) {
206  "Failed to resolve hostname %s: %s\n",
207  hostname, gai_strerror(ret));
208  return AVERROR(EIO);
209  }
210 
211  cur_ai = ai;
212 
213 #if HAVE_STRUCT_SOCKADDR_IN6
214  // workaround for IOS9 getaddrinfo in IPv6 only network use hardcode IPv4 address can not resolve port number.
215  if (cur_ai->ai_family == AF_INET6){
216  struct sockaddr_in6 * sockaddr_v6 = (struct sockaddr_in6 *)cur_ai->ai_addr;
217  if (!sockaddr_v6->sin6_port){
218  sockaddr_v6->sin6_port = htons(port);
219  }
220  }
221 #endif
222 
223  if (s->listen > 0) {
224  while (cur_ai && fd < 0) {
225  fd = ff_socket(cur_ai->ai_family,
226  cur_ai->ai_socktype,
227  cur_ai->ai_protocol, h);
228  if (fd < 0) {
229  ret = ff_neterrno();
230  cur_ai = cur_ai->ai_next;
231  }
232  }
233  if (fd < 0)
234  goto fail1;
235  customize_fd(s, fd, cur_ai->ai_family);
236  }
237 
238  if (s->listen == 2) {
239  // multi-client
240  if ((ret = ff_listen(fd, cur_ai->ai_addr, cur_ai->ai_addrlen, h)) < 0)
241  goto fail1;
242  } else if (s->listen == 1) {
243  // single client
244  if ((ret = ff_listen_bind(fd, cur_ai->ai_addr, cur_ai->ai_addrlen,
245  s->listen_timeout, h)) < 0)
246  goto fail1;
247  // Socket descriptor already closed here. Safe to overwrite to client one.
248  fd = ret;
249  } else {
250  ret = ff_connect_parallel(ai, s->open_timeout / 1000, 3, h, &fd, customize_fd, s);
251  if (ret < 0)
252  goto fail1;
253  }
254 
255  h->is_streamed = 1;
256  s->fd = fd;
257 
258  freeaddrinfo(ai);
259  return 0;
260 
261  fail1:
262  if (fd >= 0)
263  closesocket(fd);
264  freeaddrinfo(ai);
265  return ret;
266 }
267 
269 {
270  TCPContext *sc = s->priv_data;
271  TCPContext *cc;
272  int ret;
273  av_assert0(sc->listen);
274  if ((ret = ffurl_alloc(c, s->filename, s->flags, &s->interrupt_callback)) < 0)
275  return ret;
276  cc = (*c)->priv_data;
277  ret = ff_accept(sc->fd, sc->listen_timeout, s);
278  if (ret < 0) {
279  ffurl_closep(c);
280  return ret;
281  }
282  cc->fd = ret;
283  return 0;
284 }
285 
286 static int tcp_read(URLContext *h, uint8_t *buf, int size)
287 {
288  TCPContext *s = h->priv_data;
289  int ret;
290 
291  if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
292  ret = ff_network_wait_fd_timeout(s->fd, 0, h->rw_timeout, &h->interrupt_callback);
293  if (ret)
294  return ret;
295  }
296  ret = recv(s->fd, buf, size, 0);
297  if (ret == 0)
298  return AVERROR_EOF;
299  return ret < 0 ? ff_neterrno() : ret;
300 }
301 
302 static int tcp_write(URLContext *h, const uint8_t *buf, int size)
303 {
304  TCPContext *s = h->priv_data;
305  int ret;
306 
307  if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
308  ret = ff_network_wait_fd_timeout(s->fd, 1, h->rw_timeout, &h->interrupt_callback);
309  if (ret)
310  return ret;
311  }
312  ret = send(s->fd, buf, size, MSG_NOSIGNAL);
313  return ret < 0 ? ff_neterrno() : ret;
314 }
315 
316 static int tcp_shutdown(URLContext *h, int flags)
317 {
318  TCPContext *s = h->priv_data;
319  int how;
320 
322  how = SHUT_RDWR;
323  } else if (flags & AVIO_FLAG_WRITE) {
324  how = SHUT_WR;
325  } else {
326  how = SHUT_RD;
327  }
328 
329  return shutdown(s->fd, how);
330 }
331 
332 static int tcp_close(URLContext *h)
333 {
334  TCPContext *s = h->priv_data;
335  closesocket(s->fd);
336  return 0;
337 }
338 
340 {
341  TCPContext *s = h->priv_data;
342  return s->fd;
343 }
344 
346 {
347  TCPContext *s = h->priv_data;
348  int avail;
349  socklen_t avail_len = sizeof(avail);
350 
351 #if HAVE_WINSOCK2_H
352  /* SO_RCVBUF with winsock only reports the actual TCP window size when
353  auto-tuning has been disabled via setting SO_RCVBUF */
354  if (s->recv_buffer_size < 0) {
355  return AVERROR(ENOSYS);
356  }
357 #endif
358 
359  if (getsockopt(s->fd, SOL_SOCKET, SO_RCVBUF, &avail, &avail_len)) {
360  return ff_neterrno();
361  }
362  return avail;
363 }
364 
366  .name = "tcp",
367  .url_open = tcp_open,
368  .url_accept = tcp_accept,
369  .url_read = tcp_read,
370  .url_write = tcp_write,
371  .url_close = tcp_close,
372  .url_get_file_handle = tcp_get_file_handle,
373  .url_get_short_seek = tcp_get_window_size,
374  .url_shutdown = tcp_shutdown,
375  .priv_data_size = sizeof(TCPContext),
377  .priv_data_class = &tcp_class,
378 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:215
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
opt.h
av_find_info_tag
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Definition: parseutils.c:756
E
#define E
Definition: tcp.c:54
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Definition: tcp.c:268
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#define URL_PROTOCOL_FLAG_NETWORK
Definition: url.h:33
TCPContext::tcp_mss
int tcp_mss
Definition: tcp.c:48
AVERROR_EOF
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End of file.
Definition: error.h:57
OFFSET
#define OFFSET(x)
Definition: tcp.c:52
TCPContext::local_addr
char * local_addr
Definition: tcp.c:40
tcp_write
static int tcp_write(URLContext *h, const uint8_t *buf, int size)
Definition: tcp.c:302
AVOption
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Definition: opt.h:429
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void ff_log_net_error(void *ctx, int level, const char *prefix)
Definition: network.c:587
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Definition: url.h:51
os_support.h
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#define freeaddrinfo
Definition: network.h:218
ff_listen_bind
int ff_listen_bind(int fd, const struct sockaddr *addr, socklen_t addrlen, int timeout, URLContext *h)
Bind to a file descriptor and poll for a connection.
Definition: network.c:251
avassert.h
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:209
TCPContext::rw_timeout
int rw_timeout
Definition: tcp.c:42
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Definition: tcp.c:37
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static int customize_fd(void *ctx, int fd, int family)
Definition: tcp.c:77
s
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Definition: cbs_vp9.c:198
av_assert0
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assert() equivalent, that is always enabled.
Definition: avassert.h:40
AVIO_FLAG_WRITE
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write-only
Definition: avio.h:618
tcp_open
static int tcp_open(URLContext *h, const char *uri, int flags)
Definition: tcp.c:140
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Definition: movenc.c:49
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int listen
Definition: tcp.c:38
if
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Definition: filter_design.txt:179
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Definition: tcp.c:286
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Definition: version.h:85
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Definition: log.h:75
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Definition: coverity.c:32
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int send_buffer_size
Definition: tcp.c:45
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const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
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Definition: swscale.c:42
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This works similarly to ff_network_wait_fd, but waits up to 'timeout' microseconds Uses ff_network_wa...
Definition: network.c:83
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#define ff_neterrno()
Definition: network.h:68
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Definition: tcp.c:39
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static const AVOption options[]
Definition: tcp.c:55
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
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Definition: tcp.c:332
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Definition: tcp.c:365
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Definition: network.h:139
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Definition: tcp.c:35
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Poll for a single connection on the passed file descriptor.
Definition: network.c:233
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Definition: twinvq_data.h:10344
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Definition: url.h:52
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Definition: tcp.c:339
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Definition: tcp.c:345
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Definition: network.h:225
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Definition: tcp.c:46
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int ffurl_alloc(URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb)
Create a URLContext for accessing to the resource indicated by url, but do not initiate the connectio...
Definition: avio.c:349
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Definition: network.h:217
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int recv_buffer_size
Definition: tcp.c:44
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int listen_timeout
Definition: tcp.c:43
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Definition: url.h:35
TCPContext::open_timeout
int open_timeout
Definition: tcp.c:41
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Split a URL string into components.
Definition: utils.c:351
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D
#define D
Definition: tcp.c:53
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Connect to any of the given addrinfo addresses, with multiple attempts running in parallel.
Definition: network.c:412
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static int tcp_shutdown(URLContext *h, int flags)
Definition: tcp.c:316
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int ffurl_closep(URLContext **hh)
Close the resource accessed by the URLContext h, and free the memory used by it.
Definition: avio.c:588
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Definition: filter_design.txt:187
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:80
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int ai_socktype
Definition: network.h:140
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ff_listen
int ff_listen(int fd, const struct sockaddr *addr, socklen_t addrlen, void *logctx)
Bind to a file descriptor to an address without accepting connections.
Definition: network.c:215
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static const AVClass tcp_class
Definition: tcp.c:70
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Definition: network.h:138
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@ AV_OPT_TYPE_INT
Underlying C type is int.
Definition: opt.h:259
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#define AVIO_FLAG_READ
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Definition: avio.h:617
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char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:272
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#define MSG_NOSIGNAL
Definition: network.h:133
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Underlying C type is int.
Definition: opt.h:327
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#define AVIO_FLAG_NONBLOCK
Use non-blocking mode.
Definition: avio.h:636
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#define av_log(a,...)
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h
h
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int ff_socket(int af, int type, int proto, void *logctx)
Definition: network.c:188
AV_OPT_TYPE_STRING
@ AV_OPT_TYPE_STRING
Underlying C type is a uint8_t* that is either NULL or points to a C string allocated with the av_mal...
Definition: opt.h:276
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#define snprintf
Definition: snprintf.h:34
AI_PASSIVE
#define AI_PASSIVE
Definition: network.h:179