1 /* Declarations of socket constants, types, and functions. 2 Copyright (C) 1991-2022 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 <https://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 <bits/types/struct_iovec.h> 27 #define __need_size_t 28 #include <stddef.h> 29 30 /* This operating system-specific header file defines the SOCK_*, PF_*, 31 AF_*, MSG_*, SOL_*, and SO_* constants, and the `struct sockaddr', 32 `struct msghdr', and `struct linger' types. */ 33 #include <bits/socket.h> 34 35 #ifdef __USE_MISC 36 # include <bits/types/struct_osockaddr.h> 37 #endif 38 39 /* The following constants should be used for the second parameter of 40 `shutdown'. */ 41 enum 42 { 43 SHUT_RD = 0, /* No more receptions. */ 44 #define SHUT_RD SHUT_RD 45 SHUT_WR, /* No more transmissions. */ 46 #define SHUT_WR SHUT_WR 47 SHUT_RDWR /* No more receptions or transmissions. */ 48 #define SHUT_RDWR SHUT_RDWR 49 }; 50 51 /* This is the type we use for generic socket address arguments. 52 53 With GCC 2.7 and later, the funky union causes redeclarations or 54 uses with any of the listed types to be allowed without complaint. 55 G++ 2.7 does not support transparent unions so there we want the 56 old-style declaration, too. */ 57 #if defined __cplusplus || !__GNUC_PREREQ (2, 7) || !defined __USE_GNU 58 # define __SOCKADDR_ARG struct sockaddr *__restrict 59 # define __CONST_SOCKADDR_ARG const struct sockaddr * 60 #else 61 /* Add more `struct sockaddr_AF' types here as necessary. 62 These are all the ones I found on NetBSD and Linux. */ 63 # define __SOCKADDR_ALLTYPES \ 64 __SOCKADDR_ONETYPE (sockaddr) \ 65 __SOCKADDR_ONETYPE (sockaddr_at) \ 66 __SOCKADDR_ONETYPE (sockaddr_ax25) \ 67 __SOCKADDR_ONETYPE (sockaddr_dl) \ 68 __SOCKADDR_ONETYPE (sockaddr_eon) \ 69 __SOCKADDR_ONETYPE (sockaddr_in) \ 70 __SOCKADDR_ONETYPE (sockaddr_in6) \ 71 __SOCKADDR_ONETYPE (sockaddr_inarp) \ 72 __SOCKADDR_ONETYPE (sockaddr_ipx) \ 73 __SOCKADDR_ONETYPE (sockaddr_iso) \ 74 __SOCKADDR_ONETYPE (sockaddr_ns) \ 75 __SOCKADDR_ONETYPE (sockaddr_un) \ 76 __SOCKADDR_ONETYPE (sockaddr_x25) 77 78 # define __SOCKADDR_ONETYPE(type) struct type *__restrict __##type##__; 79 typedef union { __SOCKADDR_ALLTYPES 80 } __SOCKADDR_ARG __attribute__ ((__transparent_union__)); 81 # undef __SOCKADDR_ONETYPE 82 # define __SOCKADDR_ONETYPE(type) const struct type *__restrict __##type##__; 83 typedef union { __SOCKADDR_ALLTYPES 84 } __CONST_SOCKADDR_ARG __attribute__ ((__transparent_union__)); 85 # undef __SOCKADDR_ONETYPE 86 #endif 87 88 #ifdef __USE_GNU 89 /* For `recvmmsg' and `sendmmsg'. */ 90 struct mmsghdr 91 { 92 struct msghdr msg_hdr; /* Actual message header. */ 93 unsigned int msg_len; /* Number of received or sent bytes for the 94 entry. */ 95 }; 96 #endif 97 98 99 /* Create a new socket of type TYPE in domain DOMAIN, using 100 protocol PROTOCOL. If PROTOCOL is zero, one is chosen automatically. 101 Returns a file descriptor for the new socket, or -1 for errors. */ 102 extern int socket (int __domain, int __type, int __protocol) __THROW; 103 104 /* Create two new sockets, of type TYPE in domain DOMAIN and using 105 protocol PROTOCOL, which are connected to each other, and put file 106 descriptors for them in FDS[0] and FDS[1]. If PROTOCOL is zero, 107 one will be chosen automatically. Returns 0 on success, -1 for errors. */ 108 extern int socketpair (int __domain, int __type, int __protocol, 109 int __fds[2]) __THROW; 110 111 /* Give the socket FD the local address ADDR (which is LEN bytes long). */ 112 extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len) 113 __THROW; 114 115 /* Put the local address of FD into *ADDR and its length in *LEN. */ 116 extern int getsockname (int __fd, __SOCKADDR_ARG __addr, 117 socklen_t *__restrict __len) __THROW; 118 119 /* Open a connection on socket FD to peer at ADDR (which LEN bytes long). 120 For connectionless socket types, just set the default address to send to 121 and the only address from which to accept transmissions. 122 Return 0 on success, -1 for errors. 123 124 This function is a cancellation point and therefore not marked with 125 __THROW. */ 126 extern int connect (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len); 127 128 /* Put the address of the peer connected to socket FD into *ADDR 129 (which is *LEN bytes long), and its actual length into *LEN. */ 130 extern int getpeername (int __fd, __SOCKADDR_ARG __addr, 131 socklen_t *__restrict __len) __THROW; 132 133 134 /* Send N bytes of BUF to socket FD. Returns the number sent or -1. 135 136 This function is a cancellation point and therefore not marked with 137 __THROW. */ 138 extern ssize_t send (int __fd, const void *__buf, size_t __n, int __flags); 139 140 /* Read N bytes into BUF from socket FD. 141 Returns the number read or -1 for errors. 142 143 This function is a cancellation point and therefore not marked with 144 __THROW. */ 145 extern ssize_t recv (int __fd, void *__buf, size_t __n, int __flags); 146 147 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is 148 ADDR_LEN bytes long). Returns the number sent, or -1 for errors. 149 150 This function is a cancellation point and therefore not marked with 151 __THROW. */ 152 extern ssize_t sendto (int __fd, const void *__buf, size_t __n, 153 int __flags, __CONST_SOCKADDR_ARG __addr, 154 socklen_t __addr_len); 155 156 /* Read N bytes into BUF through socket FD. 157 If ADDR is not NULL, fill in *ADDR_LEN bytes of it with tha address of 158 the sender, and store the actual size of the address in *ADDR_LEN. 159 Returns the number of bytes read or -1 for errors. 160 161 This function is a cancellation point and therefore not marked with 162 __THROW. */ 163 extern ssize_t recvfrom (int __fd, void *__restrict __buf, size_t __n, 164 int __flags, __SOCKADDR_ARG __addr, 165 socklen_t *__restrict __addr_len); 166 167 168 /* Send a message described MESSAGE on socket FD. 169 Returns the number of bytes sent, or -1 for errors. 170 171 This function is a cancellation point and therefore not marked with 172 __THROW. */ 173 #ifndef __USE_TIME_BITS64 174 extern ssize_t sendmsg (int __fd, const struct msghdr *__message, 175 int __flags); 176 #else 177 # ifdef __REDIRECT 178 extern ssize_t __REDIRECT (sendmsg, (int __fd, const struct msghdr *__message, 179 int __flags), 180 __sendmsg64); 181 # else 182 extern ssize_t __sendmsg64 (int __fd, const struct msghdr *__message, 183 int __flags); 184 # define sendmsg __sendmsg64 185 # endif 186 #endif 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 # ifndef __USE_TIME_BITS64 195 extern int sendmmsg (int __fd, struct mmsghdr *__vmessages, 196 unsigned int __vlen, int __flags); 197 # else 198 # ifdef __REDIRECT 199 extern int __REDIRECT (sendmmsg, (int __fd, struct mmsghdr *__vmessages, 200 unsigned int __vlen, int __flags), 201 __sendmmsg64); 202 # else 203 extern int __sendmmsg64 (int __fd, struct mmsghdr *__vmessages, 204 unsigned int __vlen, int __flags); 205 # define sendmmsg __sendmmsg64 206 # endif 207 # endif /* __USE_TIME_BITS64 */ 208 #endif /* __USE_GNU */ 209 210 /* Receive a message as described by MESSAGE from socket FD. 211 Returns the number of bytes read or -1 for errors. 212 213 This function is a cancellation point and therefore not marked with 214 __THROW. */ 215 #ifndef __USE_TIME_BITS64 216 extern ssize_t recvmsg (int __fd, struct msghdr *__message, int __flags); 217 #else 218 # ifdef __REDIRECT 219 extern ssize_t __REDIRECT (recvmsg, 220 (int __fd, struct msghdr *__message, int __flags), 221 __recvmsg64); 222 # else 223 extern ssize_t __recvmsg64 (int __fd, struct msghdr *__message, int __flags); 224 # define recvmsg __recvmsg64 225 # endif 226 #endif 227 228 #ifdef __USE_GNU 229 /* Receive up to VLEN messages as described by VMESSAGES from socket FD. 230 Returns the number of messages received or -1 for errors. 231 232 This function is a cancellation point and therefore not marked with 233 __THROW. */ 234 # ifndef __USE_TIME_BITS64 235 extern int recvmmsg (int __fd, struct mmsghdr *__vmessages, 236 unsigned int __vlen, int __flags, 237 struct timespec *__tmo); 238 # else 239 # ifdef __REDIRECT 240 extern int __REDIRECT (recvmmsg, (int __fd, struct mmsghdr *__vmessages, 241 unsigned int __vlen, int __flags, 242 struct timespec *__tmo), 243 __recvmmsg64); 244 # else 245 # define recvmmsg __recvmmsg64 246 # endif 247 # endif 248 #endif 249 250 251 /* Put the current value for socket FD's option OPTNAME at protocol level LEVEL 252 into OPTVAL (which is *OPTLEN bytes long), and set *OPTLEN to the value's 253 actual length. Returns 0 on success, -1 for errors. */ 254 #ifndef __USE_TIME_BITS64 255 extern int getsockopt (int __fd, int __level, int __optname, 256 void *__restrict __optval, 257 socklen_t *__restrict __optlen) __THROW; 258 #else 259 # ifdef __REDIRECT 260 extern int __REDIRECT_NTH (getsockopt, 261 (int __fd, int __level, int __optname, 262 void *__restrict __optval, 263 socklen_t *__restrict __optlen), 264 __getsockopt64); 265 # else 266 extern int __getsockopt64 (int __fd, int __level, int __optname, 267 void *__restrict __optval, 268 socklen_t *__restrict __optlen) __THROW; 269 # define getsockopt __getsockopt64 270 # endif 271 #endif 272 273 /* Set socket FD's option OPTNAME at protocol level LEVEL 274 to *OPTVAL (which is OPTLEN bytes long). 275 Returns 0 on success, -1 for errors. */ 276 #ifndef __USE_TIME_BITS64 277 extern int setsockopt (int __fd, int __level, int __optname, 278 const void *__optval, socklen_t __optlen) __THROW; 279 #else 280 # ifdef __REDIRECT 281 extern int __REDIRECT_NTH (setsockopt, 282 (int __fd, int __level, int __optname, 283 const void *__optval, socklen_t __optlen), 284 __setsockopt64); 285 # else 286 extern int __setsockopt64 (int __fd, int __level, int __optname, 287 const void *__optval, socklen_t __optlen) __THROW; 288 # define setsockopt __setsockopt64 289 # endif 290 #endif 291 292 293 /* Prepare to accept connections on socket FD. 294 N connection requests will be queued before further requests are refused. 295 Returns 0 on success, -1 for errors. */ 296 extern int listen (int __fd, int __n) __THROW; 297 298 /* Await a connection on socket FD. 299 When a connection arrives, open a new socket to communicate with it, 300 set *ADDR (which is *ADDR_LEN bytes long) to the address of the connecting 301 peer and *ADDR_LEN to the address's actual length, and return the 302 new socket's descriptor, or -1 for errors. 303 304 This function is a cancellation point and therefore not marked with 305 __THROW. */ 306 extern int accept (int __fd, __SOCKADDR_ARG __addr, 307 socklen_t *__restrict __addr_len); 308 309 #ifdef __USE_GNU 310 /* Similar to 'accept' but takes an additional parameter to specify flags. 311 312 This function is a cancellation point and therefore not marked with 313 __THROW. */ 314 extern int accept4 (int __fd, __SOCKADDR_ARG __addr, 315 socklen_t *__restrict __addr_len, int __flags); 316 #endif 317 318 /* Shut down all or part of the connection open on socket FD. 319 HOW determines what to shut down: 320 SHUT_RD = No more receptions; 321 SHUT_WR = No more transmissions; 322 SHUT_RDWR = No more receptions or transmissions. 323 Returns 0 on success, -1 for errors. */ 324 extern int shutdown (int __fd, int __how) __THROW; 325 326 327 #ifdef __USE_XOPEN2K 328 /* Determine whether socket is at a out-of-band mark. */ 329 extern int sockatmark (int __fd) __THROW; 330 #endif 331 332 333 #ifdef __USE_MISC 334 /* FDTYPE is S_IFSOCK or another S_IF* macro defined in <sys/stat.h>; 335 returns 1 if FD is open on an object of the indicated type, 0 if not, 336 or -1 for errors (setting errno). */ 337 extern int isfdtype (int __fd, int __fdtype) __THROW; 338 #endif 339 340 341 /* Define some macros helping to catch buffer overflows. */ 342 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function 343 # include <bits/socket2.h> 344 #endif 345 346 __END_DECLS 347 348 #endif /* sys/socket.h */ 349