1/* Declarations of socket constants, types, and functions.
2 Copyright (C) 1991-2016 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
18
19#ifndef _SYS_SOCKET_H
20#define _SYS_SOCKET_H 1
21
22#include <features.h>
23
24__BEGIN_DECLS
25
26#include <sys/uio.h>
27#define __need_size_t
28#include <stddef.h>
29#ifdef __USE_GNU
30/* Get the __sigset_t definition. */
31# include <bits/sigset.h>
32#endif
33
34
35/* This operating system-specific header file defines the SOCK_*, PF_*,
36 AF_*, MSG_*, SOL_*, and SO_* constants, and the `struct sockaddr',
37 `struct msghdr', and `struct linger' types. */
38#include <bits/socket.h>
39
40#ifdef __USE_MISC
41/* This is the 4.3 BSD `struct sockaddr' format, which is used as wire
42 format in the grotty old 4.3 `talk' protocol. */
43struct osockaddr
44 {
45 unsigned short int sa_family;
46 unsigned char sa_data[14];
47 };
48#endif
49
50/* The following constants should be used for the second parameter of
51 `shutdown'. */
52enum
53{
54 SHUT_RD = 0, /* No more receptions. */
55#define SHUT_RD SHUT_RD
56 SHUT_WR, /* No more transmissions. */
57#define SHUT_WR SHUT_WR
58 SHUT_RDWR /* No more receptions or transmissions. */
59#define SHUT_RDWR SHUT_RDWR
60};
61
62/* This is the type we use for generic socket address arguments.
63
64 With GCC 2.7 and later, the funky union causes redeclarations or
65 uses with any of the listed types to be allowed without complaint.
66 G++ 2.7 does not support transparent unions so there we want the
67 old-style declaration, too. */
68#if defined __cplusplus || !__GNUC_PREREQ (2, 7) || !defined __USE_GNU
69# define __SOCKADDR_ARG struct sockaddr *__restrict
70# define __CONST_SOCKADDR_ARG const struct sockaddr *
71#else
72/* Add more `struct sockaddr_AF' types here as necessary.
73 These are all the ones I found on NetBSD and Linux. */
74# define __SOCKADDR_ALLTYPES \
75 __SOCKADDR_ONETYPE (sockaddr) \
76 __SOCKADDR_ONETYPE (sockaddr_at) \
77 __SOCKADDR_ONETYPE (sockaddr_ax25) \
78 __SOCKADDR_ONETYPE (sockaddr_dl) \
79 __SOCKADDR_ONETYPE (sockaddr_eon) \
80 __SOCKADDR_ONETYPE (sockaddr_in) \
81 __SOCKADDR_ONETYPE (sockaddr_in6) \
82 __SOCKADDR_ONETYPE (sockaddr_inarp) \
83 __SOCKADDR_ONETYPE (sockaddr_ipx) \
84 __SOCKADDR_ONETYPE (sockaddr_iso) \
85 __SOCKADDR_ONETYPE (sockaddr_ns) \
86 __SOCKADDR_ONETYPE (sockaddr_un) \
87 __SOCKADDR_ONETYPE (sockaddr_x25)
88
89# define __SOCKADDR_ONETYPE(type) struct type *__restrict __##type##__;
90typedef union { __SOCKADDR_ALLTYPES
91 } __SOCKADDR_ARG __attribute__ ((__transparent_union__));
92# undef __SOCKADDR_ONETYPE
93# define __SOCKADDR_ONETYPE(type) const struct type *__restrict __##type##__;
94typedef union { __SOCKADDR_ALLTYPES
95 } __CONST_SOCKADDR_ARG __attribute__ ((__transparent_union__));
96# undef __SOCKADDR_ONETYPE
97#endif
98
99#ifdef __USE_GNU
100/* For `recvmmsg' and `sendmmsg'. */
101struct mmsghdr
102 {
103 struct msghdr msg_hdr; /* Actual message header. */
104 unsigned int msg_len; /* Number of received or sent bytes for the
105 entry. */
106 };
107#endif
108
109
110/* Create a new socket of type TYPE in domain DOMAIN, using
111 protocol PROTOCOL. If PROTOCOL is zero, one is chosen automatically.
112 Returns a file descriptor for the new socket, or -1 for errors. */
113extern int socket (int __domain, int __type, int __protocol) __THROW;
114
115/* Create two new sockets, of type TYPE in domain DOMAIN and using
116 protocol PROTOCOL, which are connected to each other, and put file
117 descriptors for them in FDS[0] and FDS[1]. If PROTOCOL is zero,
118 one will be chosen automatically. Returns 0 on success, -1 for errors. */
119extern int socketpair (int __domain, int __type, int __protocol,
120 int __fds[2]) __THROW;
121
122/* Give the socket FD the local address ADDR (which is LEN bytes long). */
123extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len)
124 __THROW;
125
126/* Put the local address of FD into *ADDR and its length in *LEN. */
127extern int getsockname (int __fd, __SOCKADDR_ARG __addr,
128 socklen_t *__restrict __len) __THROW;
129
130/* Open a connection on socket FD to peer at ADDR (which LEN bytes long).
131 For connectionless socket types, just set the default address to send to
132 and the only address from which to accept transmissions.
133 Return 0 on success, -1 for errors.
134
135 This function is a cancellation point and therefore not marked with
136 __THROW. */
137extern int connect (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len);
138
139/* Put the address of the peer connected to socket FD into *ADDR
140 (which is *LEN bytes long), and its actual length into *LEN. */
141extern int getpeername (int __fd, __SOCKADDR_ARG __addr,
142 socklen_t *__restrict __len) __THROW;
143
144
145/* Send N bytes of BUF to socket FD. Returns the number sent or -1.
146
147 This function is a cancellation point and therefore not marked with
148 __THROW. */
149extern ssize_t send (int __fd, const void *__buf, size_t __n, int __flags);
150
151/* Read N bytes into BUF from socket FD.
152 Returns the number read or -1 for errors.
153
154 This function is a cancellation point and therefore not marked with
155 __THROW. */
156extern ssize_t recv (int __fd, void *__buf, size_t __n, int __flags);
157
158/* Send N bytes of BUF on socket FD to peer at address ADDR (which is
159 ADDR_LEN bytes long). Returns the number sent, or -1 for errors.
160
161 This function is a cancellation point and therefore not marked with
162 __THROW. */
163extern ssize_t sendto (int __fd, const void *__buf, size_t __n,
164 int __flags, __CONST_SOCKADDR_ARG __addr,
165 socklen_t __addr_len);
166
167/* Read N bytes into BUF through socket FD.
168 If ADDR is not NULL, fill in *ADDR_LEN bytes of it with tha address of
169 the sender, and store the actual size of the address in *ADDR_LEN.
170 Returns the number of bytes read or -1 for errors.
171
172 This function is a cancellation point and therefore not marked with
173 __THROW. */
174extern ssize_t recvfrom (int __fd, void *__restrict __buf, size_t __n,
175 int __flags, __SOCKADDR_ARG __addr,
176 socklen_t *__restrict __addr_len);
177
178
179/* Send a message described MESSAGE on socket FD.
180 Returns the number of bytes sent, or -1 for errors.
181
182 This function is a cancellation point and therefore not marked with
183 __THROW. */
184extern ssize_t sendmsg (int __fd, const struct msghdr *__message,
185 int __flags);
186
187#ifdef __USE_GNU
188/* Send a VLEN messages as described by VMESSAGES to socket FD.
189 Returns the number of datagrams successfully written or -1 for errors.
190
191 This function is a cancellation point and therefore not marked with
192 __THROW. */
193extern int sendmmsg (int __fd, struct mmsghdr *__vmessages,
194 unsigned int __vlen, int __flags);
195#endif
196
197/* Receive a message as described by MESSAGE from socket FD.
198 Returns the number of bytes read or -1 for errors.
199
200 This function is a cancellation point and therefore not marked with
201 __THROW. */
202extern ssize_t recvmsg (int __fd, struct msghdr *__message, int __flags);
203
204#ifdef __USE_GNU
205/* Receive up to VLEN messages as described by VMESSAGES from socket FD.
206 Returns the number of messages received or -1 for errors.
207
208 This function is a cancellation point and therefore not marked with
209 __THROW. */
210extern int recvmmsg (int __fd, struct mmsghdr *__vmessages,
211 unsigned int __vlen, int __flags,
212 struct timespec *__tmo);
213#endif
214
215
216/* Put the current value for socket FD's option OPTNAME at protocol level LEVEL
217 into OPTVAL (which is *OPTLEN bytes long), and set *OPTLEN to the value's
218 actual length. Returns 0 on success, -1 for errors. */
219extern int getsockopt (int __fd, int __level, int __optname,
220 void *__restrict __optval,
221 socklen_t *__restrict __optlen) __THROW;
222
223/* Set socket FD's option OPTNAME at protocol level LEVEL
224 to *OPTVAL (which is OPTLEN bytes long).
225 Returns 0 on success, -1 for errors. */
226extern int setsockopt (int __fd, int __level, int __optname,
227 const void *__optval, socklen_t __optlen) __THROW;
228
229
230/* Prepare to accept connections on socket FD.
231 N connection requests will be queued before further requests are refused.
232 Returns 0 on success, -1 for errors. */
233extern int listen (int __fd, int __n) __THROW;
234
235/* Await a connection on socket FD.
236 When a connection arrives, open a new socket to communicate with it,
237 set *ADDR (which is *ADDR_LEN bytes long) to the address of the connecting
238 peer and *ADDR_LEN to the address's actual length, and return the
239 new socket's descriptor, or -1 for errors.
240
241 This function is a cancellation point and therefore not marked with
242 __THROW. */
243extern int accept (int __fd, __SOCKADDR_ARG __addr,
244 socklen_t *__restrict __addr_len);
245
246#ifdef __USE_GNU
247/* Similar to 'accept' but takes an additional parameter to specify flags.
248
249 This function is a cancellation point and therefore not marked with
250 __THROW. */
251extern int accept4 (int __fd, __SOCKADDR_ARG __addr,
252 socklen_t *__restrict __addr_len, int __flags);
253#endif
254
255/* Shut down all or part of the connection open on socket FD.
256 HOW determines what to shut down:
257 SHUT_RD = No more receptions;
258 SHUT_WR = No more transmissions;
259 SHUT_RDWR = No more receptions or transmissions.
260 Returns 0 on success, -1 for errors. */
261extern int shutdown (int __fd, int __how) __THROW;
262
263
264#ifdef __USE_XOPEN2K
265/* Determine wheter socket is at a out-of-band mark. */
266extern int sockatmark (int __fd) __THROW;
267#endif
268
269
270#ifdef __USE_MISC
271/* FDTYPE is S_IFSOCK or another S_IF* macro defined in <sys/stat.h>;
272 returns 1 if FD is open on an object of the indicated type, 0 if not,
273 or -1 for errors (setting errno). */
274extern int isfdtype (int __fd, int __fdtype) __THROW;
275#endif
276
277
278/* Define some macros helping to catch buffer overflows. */
279#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
280# include <bits/socket2.h>
281#endif
282
283__END_DECLS
284
285#endif /* sys/socket.h */
286