socket/sys/socket.h

   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
 101 /* Create a new socket of type TYPE in domain DOMAIN, using
 102    protocol PROTOCOL.  If PROTOCOL is zero, one is chosen automatically.
 103    Returns a file descriptor for the new socket, or -1 for errors.  */
 104 extern int socket (int __domain, int __type, int __protocol) __THROW;
 105
 106 /* Create two new sockets, of type TYPE in domain DOMAIN and using
 107    protocol PROTOCOL, which are connected to each other, and put file
 108    descriptors for them in FDS[0] and FDS[1].  If PROTOCOL is zero,
 109    one will be chosen automatically.  Returns 0 on success, -1 for errors.  */
 110 extern int socketpair (int __domain, int __type, int __protocol,
 111                        int __fds[2]) __THROW;
 112
 113 /* Give the socket FD the local address ADDR (which is LEN bytes long).  */
 114 extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len)
 115      __THROW;
 116
 117 /* Put the local address of FD into *ADDR and its length in *LEN.  */
 118 extern int getsockname (int __fd, __SOCKADDR_ARG __addr,
 119                         socklen_t *__restrict __len) __THROW;
 120
 121 /* Open a connection on socket FD to peer at ADDR (which LEN bytes long).
 122    For connectionless socket types, just set the default address to send to
 123    and the only address from which to accept transmissions.
 124    Return 0 on success, -1 for errors.
 125
 126    This function is a cancellation point and therefore not marked with
 127    __THROW.  */
 128 extern int connect (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len);
 129
 130 /* Put the address of the peer connected to socket FD into *ADDR
 131    (which is *LEN bytes long), and its actual length into *LEN.  */
 132 extern int getpeername (int __fd, __SOCKADDR_ARG __addr,
 133                         socklen_t *__restrict __len) __THROW;
 134
 135
 136 /* Send N bytes of BUF to socket FD.  Returns the number sent or -1.
 137
 138    This function is a cancellation point and therefore not marked with
 139    __THROW.  */
 140 extern ssize_t send (int __fd, const void *__buf, size_t __n, int __flags);
 141
 142 /* Read N bytes into BUF from socket FD.
 143    Returns the number read or -1 for errors.
 144
 145    This function is a cancellation point and therefore not marked with
 146    __THROW.  */
 147 extern ssize_t recv (int __fd, void *__buf, size_t __n, int __flags);
 148
 149 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is
 150    ADDR_LEN bytes long).  Returns the number sent, or -1 for errors.
 151
 152    This function is a cancellation point and therefore not marked with
 153    __THROW.  */
 154 extern ssize_t sendto (int __fd, const void *__buf, size_t __n,
 155                        int __flags, __CONST_SOCKADDR_ARG __addr,
 156                        socklen_t __addr_len);
 157
 158 /* Read N bytes into BUF through socket FD.
 159    If ADDR is not NULL, fill in *ADDR_LEN bytes of it with tha address of
 160    the sender, and store the actual size of the address in *ADDR_LEN.
 161    Returns the number of bytes read or -1 for errors.
 162
 163    This function is a cancellation point and therefore not marked with
 164    __THROW.  */
 165 extern ssize_t recvfrom (int __fd, void *__restrict __buf, size_t __n,
 166                          int __flags, __SOCKADDR_ARG __addr,
 167                          socklen_t *__restrict __addr_len);
 168
 169
 170 /* Send a message described MESSAGE on socket FD.
 171    Returns the number of bytes sent, or -1 for errors.
 172
 173    This function is a cancellation point and therefore not marked with
 174    __THROW.  */
 175 extern ssize_t sendmsg (int __fd, const struct msghdr *__message,
 176                         int __flags);
 177
 178 /* Receive a message as described by MESSAGE from socket FD.
 179    Returns the number of bytes read or -1 for errors.
 180
 181    This function is a cancellation point and therefore not marked with
 182    __THROW.  */
 183 extern ssize_t recvmsg (int __fd, struct msghdr *__message, int __flags);
 184
 185
 186 /* Put the current value for socket FD's option OPTNAME at protocol level LEVEL
 187    into OPTVAL (which is *OPTLEN bytes long), and set *OPTLEN to the value's
 188    actual length.  Returns 0 on success, -1 for errors.  */
 189 extern int getsockopt (int __fd, int __level, int __optname,
 190                        void *__restrict __optval,
 191                        socklen_t *__restrict __optlen) __THROW;
 192
 193 /* Set socket FD's option OPTNAME at protocol level LEVEL
 194    to *OPTVAL (which is OPTLEN bytes long).
 195    Returns 0 on success, -1 for errors.  */
 196 extern int setsockopt (int __fd, int __level, int __optname,
 197                        const void *__optval, socklen_t __optlen) __THROW;
 198
 199
 200 /* Prepare to accept connections on socket FD.
 201    N connection requests will be queued before further requests are refused.
 202    Returns 0 on success, -1 for errors.  */
 203 extern int listen (int __fd, int __n) __THROW;
 204
 205 /* Await a connection on socket FD.
 206    When a connection arrives, open a new socket to communicate with it,
 207    set *ADDR (which is *ADDR_LEN bytes long) to the address of the connecting
 208    peer and *ADDR_LEN to the address's actual length, and return the
 209    new socket's descriptor, or -1 for errors.
 210
 211    This function is a cancellation point and therefore not marked with
 212    __THROW.  */
 213 extern int accept (int __fd, __SOCKADDR_ARG __addr,
 214                    socklen_t *__restrict __addr_len);
 215
 216 #ifdef __USE_GNU
 217 /* Similar to 'accept' but takes an additional parameter to specify flags.
 218
 219    This function is a cancellation point and therefore not marked with
 220    __THROW.  */
 221 extern int accept4 (int __fd, __SOCKADDR_ARG __addr,
 222                     socklen_t *__restrict __addr_len, int __flags);
 223 #endif
 224
 225 /* Shut down all or part of the connection open on socket FD.
 226    HOW determines what to shut down:
 227      SHUT_RD   = No more receptions;
 228      SHUT_WR   = No more transmissions;
 229      SHUT_RDWR = No more receptions or transmissions.
 230    Returns 0 on success, -1 for errors.  */
 231 extern int shutdown (int __fd, int __how) __THROW;
 232
 233
 234 #ifdef __USE_XOPEN2K
 235 /* Determine wheter socket is at a out-of-band mark.  */
 236 extern int sockatmark (int __fd) __THROW;
 237 #endif
 238
 239
 240 #ifdef __USE_MISC
 241 /* FDTYPE is S_IFSOCK or another S_IF* macro defined in <sys/stat.h>;
 242    returns 1 if FD is open on an object of the indicated type, 0 if not,
 243    or -1 for errors (setting errno).  */
 244 extern int isfdtype (int __fd, int __fdtype) __THROW;
 245 #endif
 246
 247
 248 /* Define some macros helping to catch buffer overflows.  */
 249 #if __USE_FORTIFY_LEVEL > 0 && defined __extern_always_inline
 250 # include <bits/socket2.h>
 251 #endif
 252
 253 __END_DECLS
 254
 255 #endif /* sys/socket.h */