socket/sys/socket.h

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