1 /* Declarations of socket constants, types, and functions.
2    Copyright (C) 1991,92,1994-2001,2003,2005,2007,2008,2012
3    Free Software Foundation, Inc.
4    This file is part of the GNU C Library.
5 
6    The GNU C Library is free software; you can redistribute it and/or
7    modify it under the terms of the GNU Lesser General Public
8    License as published by the Free Software Foundation; either
9    version 2.1 of the License, or (at your option) any later version.
10 
11    The GNU C Library is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14    Lesser General Public License for more details.
15 
16    You should have received a copy of the GNU Lesser General Public
17    License along with the GNU C Library; if not, see
18    <http://www.gnu.org/licenses/>.  */
19 
20 #ifndef	_SYS_SOCKET_H
21 #define	_SYS_SOCKET_H	1
22 
23 #include <features.h>
24 
25 __BEGIN_DECLS
26 
27 #include <sys/uio.h>
28 #define	__need_size_t
29 #include <stddef.h>
30 #ifdef __USE_GNU
31 /* Get the __sigset_t definition.  */
32 # include <bits/sigset.h>
33 #endif
34 
35 
36 /* This operating system-specific header file defines the SOCK_*, PF_*,
37    AF_*, MSG_*, SOL_*, and SO_* constants, and the `struct sockaddr',
38    `struct msghdr', and `struct linger' types.  */
39 #include <bits/socket.h>
40 
41 #ifdef __USE_BSD
42 /* This is the 4.3 BSD `struct sockaddr' format, which is used as wire
43    format in the grotty old 4.3 `talk' protocol.  */
44 struct osockaddr
45   {
46     unsigned short int sa_family;
47     unsigned char sa_data[14];
48   };
49 #endif
50 
51 /* The following constants should be used for the second parameter of
52    `shutdown'.  */
53 enum
54 {
55   SHUT_RD = 0,		/* No more receptions.  */
56 #define SHUT_RD		SHUT_RD
57   SHUT_WR,		/* No more transmissions.  */
58 #define SHUT_WR		SHUT_WR
59   SHUT_RDWR		/* No more receptions or transmissions.  */
60 #define SHUT_RDWR	SHUT_RDWR
61 };
62 
63 /* This is the type we use for generic socket address arguments.
64 
65    With GCC 2.7 and later, the funky union causes redeclarations or
66    uses with any of the listed types to be allowed without complaint.
67    G++ 2.7 does not support transparent unions so there we want the
68    old-style declaration, too.  */
69 #if defined __cplusplus || !__GNUC_PREREQ (2, 7) || !defined __USE_GNU
70 # define __SOCKADDR_ARG		struct sockaddr *__restrict
71 # define __CONST_SOCKADDR_ARG	const struct sockaddr *
72 #else
73 /* Add more `struct sockaddr_AF' types here as necessary.
74    These are all the ones I found on NetBSD and Linux.  */
75 # define __SOCKADDR_ALLTYPES \
76   __SOCKADDR_ONETYPE (sockaddr) \
77   __SOCKADDR_ONETYPE (sockaddr_at) \
78   __SOCKADDR_ONETYPE (sockaddr_ax25) \
79   __SOCKADDR_ONETYPE (sockaddr_dl) \
80   __SOCKADDR_ONETYPE (sockaddr_eon) \
81   __SOCKADDR_ONETYPE (sockaddr_in) \
82   __SOCKADDR_ONETYPE (sockaddr_in6) \
83   __SOCKADDR_ONETYPE (sockaddr_inarp) \
84   __SOCKADDR_ONETYPE (sockaddr_ipx) \
85   __SOCKADDR_ONETYPE (sockaddr_iso) \
86   __SOCKADDR_ONETYPE (sockaddr_ns) \
87   __SOCKADDR_ONETYPE (sockaddr_un) \
88   __SOCKADDR_ONETYPE (sockaddr_x25)
89 
90 # define __SOCKADDR_ONETYPE(type) struct type *__restrict __##type##__;
91 typedef union { __SOCKADDR_ALLTYPES
92 	      } __SOCKADDR_ARG __attribute__ ((__transparent_union__));
93 # undef __SOCKADDR_ONETYPE
94 # define __SOCKADDR_ONETYPE(type) const struct type *__restrict __##type##__;
95 typedef union { __SOCKADDR_ALLTYPES
96 	      } __CONST_SOCKADDR_ARG __attribute__ ((__transparent_union__));
97 # undef __SOCKADDR_ONETYPE
98 #endif
99 
100 #ifdef __USE_GNU
101 /* For `recvmmsg' and `sendmmsg'.  */
102 struct mmsghdr
103   {
104     struct msghdr msg_hdr;	/* Actual message header.  */
105     unsigned int msg_len;	/* Number of received or sent bytes for the
106 				   entry.  */
107   };
108 #endif
109 
110 
111 /* Create a new socket of type TYPE in domain DOMAIN, using
112    protocol PROTOCOL.  If PROTOCOL is zero, one is chosen automatically.
113    Returns a file descriptor for the new socket, or -1 for errors.  */
114 extern int socket (int __domain, int __type, int __protocol) __THROW;
115 
116 /* Create two new sockets, of type TYPE in domain DOMAIN and using
117    protocol PROTOCOL, which are connected to each other, and put file
118    descriptors for them in FDS[0] and FDS[1].  If PROTOCOL is zero,
119    one will be chosen automatically.  Returns 0 on success, -1 for errors.  */
120 extern int socketpair (int __domain, int __type, int __protocol,
121 		       int __fds[2]) __THROW;
122 
123 /* Give the socket FD the local address ADDR (which is LEN bytes long).  */
124 extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len)
125      __THROW;
126 
127 /* Put the local address of FD into *ADDR and its length in *LEN.  */
128 extern int getsockname (int __fd, __SOCKADDR_ARG __addr,
129 			socklen_t *__restrict __len) __THROW;
130 
131 /* Open a connection on socket FD to peer at ADDR (which LEN bytes long).
132    For connectionless socket types, just set the default address to send to
133    and the only address from which to accept transmissions.
134    Return 0 on success, -1 for errors.
135 
136    This function is a cancellation point and therefore not marked with
137    __THROW.  */
138 extern int connect (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len);
139 
140 /* Put the address of the peer connected to socket FD into *ADDR
141    (which is *LEN bytes long), and its actual length into *LEN.  */
142 extern int getpeername (int __fd, __SOCKADDR_ARG __addr,
143 			socklen_t *__restrict __len) __THROW;
144 
145 
146 /* Send N bytes of BUF to socket FD.  Returns the number sent or -1.
147 
148    This function is a cancellation point and therefore not marked with
149    __THROW.  */
150 extern ssize_t send (int __fd, const void *__buf, size_t __n, int __flags);
151 
152 /* Read N bytes into BUF from socket FD.
153    Returns the number read or -1 for errors.
154 
155    This function is a cancellation point and therefore not marked with
156    __THROW.  */
157 extern ssize_t recv (int __fd, void *__buf, size_t __n, int __flags);
158 
159 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is
160    ADDR_LEN bytes long).  Returns the number sent, or -1 for errors.
161 
162    This function is a cancellation point and therefore not marked with
163    __THROW.  */
164 extern ssize_t sendto (int __fd, const void *__buf, size_t __n,
165 		       int __flags, __CONST_SOCKADDR_ARG __addr,
166 		       socklen_t __addr_len);
167 
168 /* Read N bytes into BUF through socket FD.
169    If ADDR is not NULL, fill in *ADDR_LEN bytes of it with tha address of
170    the sender, and store the actual size of the address in *ADDR_LEN.
171    Returns the number of bytes read or -1 for errors.
172 
173    This function is a cancellation point and therefore not marked with
174    __THROW.  */
175 extern ssize_t recvfrom (int __fd, void *__restrict __buf, size_t __n,
176 			 int __flags, __SOCKADDR_ARG __addr,
177 			 socklen_t *__restrict __addr_len);
178 
179 
180 /* Send a message described MESSAGE on socket FD.
181    Returns the number of bytes sent, or -1 for errors.
182 
183    This function is a cancellation point and therefore not marked with
184    __THROW.  */
185 extern ssize_t sendmsg (int __fd, const struct msghdr *__message,
186 			int __flags);
187 
188 #ifdef __USE_GNU
189 /* Send a VLEN messages as described by VMESSAGES to socket FD.
190    Returns the number of datagrams successfully written or -1 for errors.
191 
192    This function is a cancellation point and therefore not marked with
193    __THROW.  */
194 extern int sendmmsg (int __fd, struct mmsghdr *__vmessages,
195 		     unsigned int __vlen, int __flags);
196 #endif
197 
198 /* Receive a message as described by MESSAGE from socket FD.
199    Returns the number of bytes read or -1 for errors.
200 
201    This function is a cancellation point and therefore not marked with
202    __THROW.  */
203 extern ssize_t recvmsg (int __fd, struct msghdr *__message, int __flags);
204 
205 #ifdef __USE_GNU
206 /* Receive up to VLEN messages as described by VMESSAGES from socket FD.
207    Returns the number of bytes read or -1 for errors.
208 
209    This function is a cancellation point and therefore not marked with
210    __THROW.  */
211 extern int recvmmsg (int __fd, struct mmsghdr *__vmessages,
212 		     unsigned int __vlen, int __flags,
213 		     const struct timespec *__tmo);
214 #endif
215 
216 
217 /* Put the current value for socket FD's option OPTNAME at protocol level LEVEL
218    into OPTVAL (which is *OPTLEN bytes long), and set *OPTLEN to the value's
219    actual length.  Returns 0 on success, -1 for errors.  */
220 extern int getsockopt (int __fd, int __level, int __optname,
221 		       void *__restrict __optval,
222 		       socklen_t *__restrict __optlen) __THROW;
223 
224 /* Set socket FD's option OPTNAME at protocol level LEVEL
225    to *OPTVAL (which is OPTLEN bytes long).
226    Returns 0 on success, -1 for errors.  */
227 extern int setsockopt (int __fd, int __level, int __optname,
228 		       const void *__optval, socklen_t __optlen) __THROW;
229 
230 
231 /* Prepare to accept connections on socket FD.
232    N connection requests will be queued before further requests are refused.
233    Returns 0 on success, -1 for errors.  */
234 extern int listen (int __fd, int __n) __THROW;
235 
236 /* Await a connection on socket FD.
237    When a connection arrives, open a new socket to communicate with it,
238    set *ADDR (which is *ADDR_LEN bytes long) to the address of the connecting
239    peer and *ADDR_LEN to the address's actual length, and return the
240    new socket's descriptor, or -1 for errors.
241 
242    This function is a cancellation point and therefore not marked with
243    __THROW.  */
244 extern int accept (int __fd, __SOCKADDR_ARG __addr,
245 		   socklen_t *__restrict __addr_len);
246 
247 #ifdef __USE_GNU
248 /* Similar to 'accept' but takes an additional parameter to specify flags.
249 
250    This function is a cancellation point and therefore not marked with
251    __THROW.  */
252 extern int accept4 (int __fd, __SOCKADDR_ARG __addr,
253 		    socklen_t *__restrict __addr_len, int __flags);
254 #endif
255 
256 /* Shut down all or part of the connection open on socket FD.
257    HOW determines what to shut down:
258      SHUT_RD   = No more receptions;
259      SHUT_WR   = No more transmissions;
260      SHUT_RDWR = No more receptions or transmissions.
261    Returns 0 on success, -1 for errors.  */
262 extern int shutdown (int __fd, int __how) __THROW;
263 
264 
265 #ifdef __USE_XOPEN2K
266 /* Determine wheter socket is at a out-of-band mark.  */
267 extern int sockatmark (int __fd) __THROW;
268 #endif
269 
270 
271 #ifdef __USE_MISC
272 /* FDTYPE is S_IFSOCK or another S_IF* macro defined in <sys/stat.h>;
273    returns 1 if FD is open on an object of the indicated type, 0 if not,
274    or -1 for errors (setting errno).  */
275 extern int isfdtype (int __fd, int __fdtype) __THROW;
276 #endif
277 
278 
279 /* Define some macros helping to catch buffer overflows.  */
280 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
281 # include <bits/socket2.h>
282 #endif
283 
284 __END_DECLS
285 
286 #endif /* sys/socket.h */
287