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/parseutils.h"
24 #include "libavutil/opt.h"
25 #include "libavutil/time.h"
26 
27 #include "internal.h"
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;
45 #if !HAVE_WINSOCK2_H
46  int tcp_mss;
47 #endif /* !HAVE_WINSOCK2_H */
48 } TCPContext;
49 
50 #define OFFSET(x) offsetof(TCPContext, x)
51 #define D AV_OPT_FLAG_DECODING_PARAM
52 #define E AV_OPT_FLAG_ENCODING_PARAM
53 static const AVOption options[] = {
54  { "listen", "Listen for incoming connections", OFFSET(listen), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 2, .flags = D|E },
55  { "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 },
56  { "listen_timeout", "Connection awaiting timeout (in milliseconds)", OFFSET(listen_timeout), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
57  { "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 },
58  { "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 },
59  { "tcp_nodelay", "Use TCP_NODELAY to disable nagle's algorithm", OFFSET(tcp_nodelay), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, .flags = D|E },
60 #if !HAVE_WINSOCK2_H
61  { "tcp_mss", "Maximum segment size for outgoing TCP packets", OFFSET(tcp_mss), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
62 #endif /* !HAVE_WINSOCK2_H */
63  { NULL }
64 };
65 
66 static const AVClass tcp_class = {
67  .class_name = "tcp",
68  .item_name = av_default_item_name,
69  .option = options,
70  .version = LIBAVUTIL_VERSION_INT,
71 };
72 
73 static void customize_fd(void *ctx, int fd)
74 {
75  TCPContext *s = ctx;
76  /* Set the socket's send or receive buffer sizes, if specified.
77  If unspecified or setting fails, system default is used. */
78  if (s->recv_buffer_size > 0) {
79  if (setsockopt (fd, SOL_SOCKET, SO_RCVBUF, &s->recv_buffer_size, sizeof (s->recv_buffer_size))) {
80  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(SO_RCVBUF)");
81  }
82  }
83  if (s->send_buffer_size > 0) {
84  if (setsockopt (fd, SOL_SOCKET, SO_SNDBUF, &s->send_buffer_size, sizeof (s->send_buffer_size))) {
85  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(SO_SNDBUF)");
86  }
87  }
88  if (s->tcp_nodelay > 0) {
89  if (setsockopt (fd, IPPROTO_TCP, TCP_NODELAY, &s->tcp_nodelay, sizeof (s->tcp_nodelay))) {
90  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(TCP_NODELAY)");
91  }
92  }
93 #if !HAVE_WINSOCK2_H
94  if (s->tcp_mss > 0) {
95  if (setsockopt (fd, IPPROTO_TCP, TCP_MAXSEG, &s->tcp_mss, sizeof (s->tcp_mss))) {
96  ff_log_net_error(ctx, AV_LOG_WARNING, "setsockopt(TCP_MAXSEG)");
97  }
98  }
99 #endif /* !HAVE_WINSOCK2_H */
100 }
101 
102 /* return non zero if error */
103 static int tcp_open(URLContext *h, const char *uri, int flags)
104 {
105  struct addrinfo hints = { 0 }, *ai, *cur_ai;
106  int port, fd = -1;
107  TCPContext *s = h->priv_data;
108  const char *p;
109  char buf[256];
110  int ret;
111  char hostname[1024],proto[1024],path[1024];
112  char portstr[10];
113  s->open_timeout = 5000000;
114 
115  av_url_split(proto, sizeof(proto), NULL, 0, hostname, sizeof(hostname),
116  &port, path, sizeof(path), uri);
117  if (strcmp(proto, "tcp"))
118  return AVERROR(EINVAL);
119  if (port <= 0 || port >= 65536) {
120  av_log(h, AV_LOG_ERROR, "Port missing in uri\n");
121  return AVERROR(EINVAL);
122  }
123  p = strchr(uri, '?');
124  if (p) {
125  if (av_find_info_tag(buf, sizeof(buf), "listen", p)) {
126  char *endptr = NULL;
127  s->listen = strtol(buf, &endptr, 10);
128  /* assume if no digits were found it is a request to enable it */
129  if (buf == endptr)
130  s->listen = 1;
131  }
132  if (av_find_info_tag(buf, sizeof(buf), "timeout", p)) {
133  s->rw_timeout = strtol(buf, NULL, 10);
134  }
135  if (av_find_info_tag(buf, sizeof(buf), "listen_timeout", p)) {
136  s->listen_timeout = strtol(buf, NULL, 10);
137  }
138  }
139  if (s->rw_timeout >= 0) {
140  s->open_timeout =
141  h->rw_timeout = s->rw_timeout;
142  }
143  hints.ai_family = AF_UNSPEC;
144  hints.ai_socktype = SOCK_STREAM;
145  snprintf(portstr, sizeof(portstr), "%d", port);
146  if (s->listen)
147  hints.ai_flags |= AI_PASSIVE;
148  if (!hostname[0])
149  ret = getaddrinfo(NULL, portstr, &hints, &ai);
150  else
151  ret = getaddrinfo(hostname, portstr, &hints, &ai);
152  if (ret) {
154  "Failed to resolve hostname %s: %s\n",
155  hostname, gai_strerror(ret));
156  return AVERROR(EIO);
157  }
158 
159  cur_ai = ai;
160 
161 #if HAVE_STRUCT_SOCKADDR_IN6
162  // workaround for IOS9 getaddrinfo in IPv6 only network use hardcode IPv4 address can not resolve port number.
163  if (cur_ai->ai_family == AF_INET6){
164  struct sockaddr_in6 * sockaddr_v6 = (struct sockaddr_in6 *)cur_ai->ai_addr;
165  if (!sockaddr_v6->sin6_port){
166  sockaddr_v6->sin6_port = htons(port);
167  }
168  }
169 #endif
170 
171  if (s->listen > 0) {
172  while (cur_ai && fd < 0) {
173  fd = ff_socket(cur_ai->ai_family,
174  cur_ai->ai_socktype,
175  cur_ai->ai_protocol);
176  if (fd < 0) {
177  ret = ff_neterrno();
178  cur_ai = cur_ai->ai_next;
179  }
180  }
181  if (fd < 0)
182  goto fail1;
183  customize_fd(s, fd);
184  }
185 
186  if (s->listen == 2) {
187  // multi-client
188  if ((ret = ff_listen(fd, cur_ai->ai_addr, cur_ai->ai_addrlen)) < 0)
189  goto fail1;
190  } else if (s->listen == 1) {
191  // single client
192  if ((ret = ff_listen_bind(fd, cur_ai->ai_addr, cur_ai->ai_addrlen,
193  s->listen_timeout, h)) < 0)
194  goto fail1;
195  // Socket descriptor already closed here. Safe to overwrite to client one.
196  fd = ret;
197  } else {
198  ret = ff_connect_parallel(ai, s->open_timeout / 1000, 3, h, &fd, customize_fd, s);
199  if (ret < 0)
200  goto fail1;
201  }
202 
203  h->is_streamed = 1;
204  s->fd = fd;
205 
206  freeaddrinfo(ai);
207  return 0;
208 
209  fail1:
210  if (fd >= 0)
211  closesocket(fd);
212  freeaddrinfo(ai);
213  return ret;
214 }
215 
217 {
218  TCPContext *sc = s->priv_data;
219  TCPContext *cc;
220  int ret;
221  av_assert0(sc->listen);
222  if ((ret = ffurl_alloc(c, s->filename, s->flags, &s->interrupt_callback)) < 0)
223  return ret;
224  cc = (*c)->priv_data;
225  ret = ff_accept(sc->fd, sc->listen_timeout, s);
226  if (ret < 0) {
227  ffurl_closep(c);
228  return ret;
229  }
230  cc->fd = ret;
231  return 0;
232 }
233 
234 static int tcp_read(URLContext *h, uint8_t *buf, int size)
235 {
236  TCPContext *s = h->priv_data;
237  int ret;
238 
239  if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
240  ret = ff_network_wait_fd_timeout(s->fd, 0, h->rw_timeout, &h->interrupt_callback);
241  if (ret)
242  return ret;
243  }
244  ret = recv(s->fd, buf, size, 0);
245  if (ret == 0)
246  return AVERROR_EOF;
247  return ret < 0 ? ff_neterrno() : ret;
248 }
249 
250 static int tcp_write(URLContext *h, const uint8_t *buf, int size)
251 {
252  TCPContext *s = h->priv_data;
253  int ret;
254 
255  if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
256  ret = ff_network_wait_fd_timeout(s->fd, 1, h->rw_timeout, &h->interrupt_callback);
257  if (ret)
258  return ret;
259  }
260  ret = send(s->fd, buf, size, MSG_NOSIGNAL);
261  return ret < 0 ? ff_neterrno() : ret;
262 }
263 
264 static int tcp_shutdown(URLContext *h, int flags)
265 {
266  TCPContext *s = h->priv_data;
267  int how;
268 
270  how = SHUT_RDWR;
271  } else if (flags & AVIO_FLAG_WRITE) {
272  how = SHUT_WR;
273  } else {
274  how = SHUT_RD;
275  }
276 
277  return shutdown(s->fd, how);
278 }
279 
280 static int tcp_close(URLContext *h)
281 {
282  TCPContext *s = h->priv_data;
283  closesocket(s->fd);
284  return 0;
285 }
286 
288 {
289  TCPContext *s = h->priv_data;
290  return s->fd;
291 }
292 
294 {
295  TCPContext *s = h->priv_data;
296  int avail;
297  socklen_t avail_len = sizeof(avail);
298 
299 #if HAVE_WINSOCK2_H
300  /* SO_RCVBUF with winsock only reports the actual TCP window size when
301  auto-tuning has been disabled via setting SO_RCVBUF */
302  if (s->recv_buffer_size < 0) {
303  return AVERROR(ENOSYS);
304  }
305 #endif
306 
307  if (getsockopt(s->fd, SOL_SOCKET, SO_RCVBUF, &avail, &avail_len)) {
308  return ff_neterrno();
309  }
310  return avail;
311 }
312 
314  .name = "tcp",
315  .url_open = tcp_open,
316  .url_accept = tcp_accept,
317  .url_read = tcp_read,
318  .url_write = tcp_write,
319  .url_close = tcp_close,
320  .url_get_file_handle = tcp_get_file_handle,
321  .url_get_short_seek = tcp_get_window_size,
322  .url_shutdown = tcp_shutdown,
323  .priv_data_size = sizeof(TCPContext),
325  .priv_data_class = &tcp_class,
326 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:187
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
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:751
E
#define E
Definition: tcp.c:52
tcp_accept
static int tcp_accept(URLContext *s, URLContext **c)
Definition: tcp.c:216
URL_PROTOCOL_FLAG_NETWORK
#define URL_PROTOCOL_FLAG_NETWORK
Definition: url.h:34
TCPContext::tcp_mss
int tcp_mss
Definition: tcp.c:46
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
OFFSET
#define OFFSET(x)
Definition: tcp.c:50
tcp_write
static int tcp_write(URLContext *h, const uint8_t *buf, int size)
Definition: tcp.c:250
AVOption
AVOption.
Definition: opt.h:248
ff_log_net_error
void ff_log_net_error(void *ctx, int level, const char *prefix)
Definition: network.c:581
ff_socket
int ff_socket(int af, int type, int proto)
Definition: network.c:183
URLProtocol
Definition: url.h:54
os_support.h
freeaddrinfo
#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:246
avassert.h
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:181
TCPContext::rw_timeout
int rw_timeout
Definition: tcp.c:40
ff_listen
int ff_listen(int fd, const struct sockaddr *addr, socklen_t addrlen)
Bind to a file descriptor to an address without accepting connections.
Definition: network.c:210
TCPContext::fd
int fd
Definition: tcp.c:37
s
#define s(width, name)
Definition: cbs_vp9.c:257
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
AVIO_FLAG_WRITE
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:675
tcp_open
static int tcp_open(URLContext *h, const char *uri, int flags)
Definition: tcp.c:103
ctx
AVFormatContext * ctx
Definition: movenc.c:48
TCPContext::listen
int listen
Definition: tcp.c:38
if
if(ret)
Definition: filter_design.txt:179
tcp_read
static int tcp_read(URLContext *h, uint8_t *buf, int size)
Definition: tcp.c:234
internal.h
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
NULL
#define NULL
Definition: coverity.c:32
TCPContext::send_buffer_size
int send_buffer_size
Definition: tcp.c:43
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
parseutils.h
ff_network_wait_fd_timeout
int ff_network_wait_fd_timeout(int fd, int write, int64_t timeout, AVIOInterruptCB *int_cb)
This works similarly to ff_network_wait_fd, but waits up to 'timeout' microseconds Uses ff_network_wa...
Definition: network.c:78
time.h
ff_neterrno
#define ff_neterrno()
Definition: network.h:68
options
static const AVOption options[]
Definition: tcp.c:53
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
tcp_close
static int tcp_close(URLContext *h)
Definition: tcp.c:280
ff_tcp_protocol
const URLProtocol ff_tcp_protocol
Definition: tcp.c:313
addrinfo::ai_family
int ai_family
Definition: network.h:139
TCPContext
Definition: tcp.c:35
ff_accept
int ff_accept(int fd, int timeout, URLContext *h)
Poll for a single connection on the passed file descriptor.
Definition: network.c:228
size
int size
Definition: twinvq_data.h:10344
URLProtocol::name
const char * name
Definition: url.h:55
tcp_get_file_handle
static int tcp_get_file_handle(URLContext *h)
Definition: tcp.c:287
tcp_get_window_size
static int tcp_get_window_size(URLContext *h)
Definition: tcp.c:293
gai_strerror
#define gai_strerror
Definition: network.h:225
TCPContext::tcp_nodelay
int tcp_nodelay
Definition: tcp.c:44
ffurl_alloc
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:293
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#define getaddrinfo
Definition: network.h:217
TCPContext::recv_buffer_size
int recv_buffer_size
Definition: tcp.c:42
TCPContext::listen_timeout
int listen_timeout
Definition: tcp.c:41
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Definition: url.h:38
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int ff_connect_parallel(struct addrinfo *addrs, int timeout_ms_per_address, int parallel, URLContext *h, int *fd, void(*customize_fd)(void *, int), void *customize_ctx)
Connect to any of the given addrinfo addresses, with multiple attempts running in parallel.
Definition: network.c:403
TCPContext::open_timeout
int open_timeout
Definition: tcp.c:39
av_url_split
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Split a URL string into components.
Definition: utils.c:4647
url.h
D
#define D
Definition: tcp.c:51
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static int tcp_shutdown(URLContext *h, int flags)
Definition: tcp.c:264
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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:435
ret
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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:72
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int ai_socktype
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Definition: tcp.c:66
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Definition: network.h:138
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:225
AVIO_FLAG_READ
#define AVIO_FLAG_READ
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Definition: avio.h:674
MSG_NOSIGNAL
#define MSG_NOSIGNAL
Definition: network.h:133
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:242
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#define AVIO_FLAG_NONBLOCK
Use non-blocking mode.
Definition: avio.h:693
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#define flags(name, subs,...)
Definition: cbs_av1.c:561
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static void customize_fd(void *ctx, int fd)
Definition: tcp.c:73
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#define av_log(a,...)
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h
h
Definition: vp9dsp_template.c:2038
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Definition: network.h:137
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Definition: snprintf.h:34
AI_PASSIVE
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Definition: network.h:179