socket/sys/socket.h

   1 /* Declarations of socket constants, types, and functions.
   2    Copyright (C) 1991,92,1994-2001,2003,2005,2007,2008
   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, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #ifndef _SYS_SOCKET_H
  22 #define _SYS_SOCKET_H   1
  23
  24 #include <features.h>
  25
  26 __BEGIN_DECLS
  27
  28 #include <sys/uio.h>
  29 #define __need_size_t
  30 #include <stddef.h>
  31 #ifdef __USE_GNU
  32 /* Get the __sigset_t definition.  */
  33 # include <bits/sigset.h>
  34 #endif
  35
  36
  37 /* This operating system-specific header file defines the SOCK_*, PF_*,
  38    AF_*, MSG_*, SOL_*, and SO_* constants, and the `struct sockaddr',
  39    `struct msghdr', and `struct linger' types.  */
  40 #include <bits/socket.h>
  41
  42 #ifdef __USE_BSD
  43 /* This is the 4.3 BSD `struct sockaddr' format, which is used as wire
  44    format in the grotty old 4.3 `talk' protocol.  */
  45 struct osockaddr
  46   {
  47     unsigned short int sa_family;
  48     unsigned char sa_data[14];
  49   };
  50 #endif
  51
  52 /* The following constants should be used for the second parameter of
  53    `shutdown'.  */
  54 enum
  55 {
  56   SHUT_RD = 0,          /* No more receptions.  */
  57 #define SHUT_RD         SHUT_RD
  58   SHUT_WR,              /* No more transmissions.  */
  59 #define SHUT_WR         SHUT_WR
  60   SHUT_RDWR             /* No more receptions or transmissions.  */
  61 #define SHUT_RDWR       SHUT_RDWR
  62 };
  63
  64 /* This is the type we use for generic socket address arguments.
  65
  66    With GCC 2.7 and later, the funky union causes redeclarations or
  67    uses with any of the listed types to be allowed without complaint.
  68    G++ 2.7 does not support transparent unions so there we want the
  69    old-style declaration, too.  */
  70 #if defined __cplusplus || !__GNUC_PREREQ (2, 7) || !defined __USE_GNU
  71 # define __SOCKADDR_ARG         struct sockaddr *__restrict
  72 # define __CONST_SOCKADDR_ARG   __const struct sockaddr *
  73 #else
  74 /* Add more `struct sockaddr_AF' types here as necessary.
  75    These are all the ones I found on NetBSD and Linux.  */
  76 # define __SOCKADDR_ALLTYPES \
  77   __SOCKADDR_ONETYPE (sockaddr) \
  78   __SOCKADDR_ONETYPE (sockaddr_at) \
  79   __SOCKADDR_ONETYPE (sockaddr_ax25) \
  80   __SOCKADDR_ONETYPE (sockaddr_dl) \
  81   __SOCKADDR_ONETYPE (sockaddr_eon) \
  82   __SOCKADDR_ONETYPE (sockaddr_in) \
  83   __SOCKADDR_ONETYPE (sockaddr_in6) \
  84   __SOCKADDR_ONETYPE (sockaddr_inarp) \
  85   __SOCKADDR_ONETYPE (sockaddr_ipx) \
  86   __SOCKADDR_ONETYPE (sockaddr_iso) \
  87   __SOCKADDR_ONETYPE (sockaddr_ns) \
  88   __SOCKADDR_ONETYPE (sockaddr_un) \
  89   __SOCKADDR_ONETYPE (sockaddr_x25)
  90
  91 # define __SOCKADDR_ONETYPE(type) struct type *__restrict __##type##__;
  92 typedef union { __SOCKADDR_ALLTYPES
  93               } __SOCKADDR_ARG __attribute__ ((__transparent_union__));
  94 # undef __SOCKADDR_ONETYPE
  95 # define __SOCKADDR_ONETYPE(type) __const struct type *__restrict __##type##__;
  96 typedef union { __SOCKADDR_ALLTYPES
  97               } __CONST_SOCKADDR_ARG __attribute__ ((__transparent_union__));
  98 # undef __SOCKADDR_ONETYPE
  99 #endif
 100
 101
 102 /* Create a new socket of type TYPE in domain DOMAIN, using
 103    protocol PROTOCOL.  If PROTOCOL is zero, one is chosen automatically.
 104    Returns a file descriptor for the new socket, or -1 for errors.  */
 105 extern int socket (int __domain, int __type, int __protocol) __THROW;
 106
 107 /* Create two new sockets, of type TYPE in domain DOMAIN and using
 108    protocol PROTOCOL, which are connected to each other, and put file
 109    descriptors for them in FDS[0] and FDS[1].  If PROTOCOL is zero,
 110    one will be chosen automatically.  Returns 0 on success, -1 for errors.  */
 111 extern int socketpair (int __domain, int __type, int __protocol,
 112                        int __fds[2]) __THROW;
 113
 114 /* Give the socket FD the local address ADDR (which is LEN bytes long).  */
 115 extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len)
 116      __THROW;
 117
 118 /* Put the local address of FD into *ADDR and its length in *LEN.  */
 119 extern int getsockname (int __fd, __SOCKADDR_ARG __addr,
 120                         socklen_t *__restrict __len) __THROW;
 121
 122 /* Open a connection on socket FD to peer at ADDR (which LEN bytes long).
 123    For connectionless socket types, just set the default address to send to
 124    and the only address from which to accept transmissions.
 125    Return 0 on success, -1 for errors.
 126
 127    This function is a cancellation point and therefore not marked with
 128    __THROW.  */
 129 extern int connect (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len);
 130
 131 /* Put the address of the peer connected to socket FD into *ADDR
 132    (which is *LEN bytes long), and its actual length into *LEN.  */
 133 extern int getpeername (int __fd, __SOCKADDR_ARG __addr,
 134                         socklen_t *__restrict __len) __THROW;
 135
 136
 137 /* Send N bytes of BUF to socket FD.  Returns the number sent or -1.
 138
 139    This function is a cancellation point and therefore not marked with
 140    __THROW.  */
 141 extern ssize_t send (int __fd, __const void *__buf, size_t __n, int __flags);
 142
 143 /* Read N bytes into BUF from socket FD.
 144    Returns the number read or -1 for errors.
 145
 146    This function is a cancellation point and therefore not marked with
 147    __THROW.  */
 148 extern ssize_t recv (int __fd, void *__buf, size_t __n, int __flags);
 149
 150 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is
 151    ADDR_LEN bytes long).  Returns the number sent, or -1 for errors.
 152
 153    This function is a cancellation point and therefore not marked with
 154    __THROW.  */
 155 extern ssize_t sendto (int __fd, __const void *__buf, size_t __n,
 156                        int __flags, __CONST_SOCKADDR_ARG __addr,
 157                        socklen_t __addr_len);
 158
 159 /* Read N bytes into BUF through socket FD.
 160    If ADDR is not NULL, fill in *ADDR_LEN bytes of it with tha address of
 161    the sender, and store the actual size of the address in *ADDR_LEN.
 162    Returns the number of bytes read or -1 for errors.
 163
 164    This function is a cancellation point and therefore not marked with
 165    __THROW.  */
 166 extern ssize_t recvfrom (int __fd, void *__restrict __buf, size_t __n,
 167                          int __flags, __SOCKADDR_ARG __addr,
 168                          socklen_t *__restrict __addr_len);
 169
 170
 171 /* Send a message described MESSAGE on socket FD.
 172    Returns the number of bytes sent, or -1 for errors.
 173
 174    This function is a cancellation point and therefore not marked with
 175    __THROW.  */
 176 extern ssize_t sendmsg (int __fd, __const struct msghdr *__message,
 177                         int __flags);
 178
 179 /* Receive a message as described by MESSAGE from socket FD.
 180    Returns the number of bytes read or -1 for errors.
 181
 182    This function is a cancellation point and therefore not marked with
 183    __THROW.  */
 184 extern ssize_t recvmsg (int __fd, struct msghdr *__message, int __flags);
 185
 186
 187 /* Put the current value for socket FD's option OPTNAME at protocol level LEVEL
 188    into OPTVAL (which is *OPTLEN bytes long), and set *OPTLEN to the value's
 189    actual length.  Returns 0 on success, -1 for errors.  */
 190 extern int getsockopt (int __fd, int __level, int __optname,
 191                        void *__restrict __optval,
 192                        socklen_t *__restrict __optlen) __THROW;
 193
 194 /* Set socket FD's option OPTNAME at protocol level LEVEL
 195    to *OPTVAL (which is OPTLEN bytes long).
 196    Returns 0 on success, -1 for errors.  */
 197 extern int setsockopt (int __fd, int __level, int __optname,
 198                        __const void *__optval, socklen_t __optlen) __THROW;
 199
 200
 201 /* Prepare to accept connections on socket FD.
 202    N connection requests will be queued before further requests are refused.
 203    Returns 0 on success, -1 for errors.  */
 204 extern int listen (int __fd, int __n) __THROW;
 205
 206 /* Await a connection on socket FD.
 207    When a connection arrives, open a new socket to communicate with it,
 208    set *ADDR (which is *ADDR_LEN bytes long) to the address of the connecting
 209    peer and *ADDR_LEN to the address's actual length, and return the
 210    new socket's descriptor, or -1 for errors.
 211
 212    This function is a cancellation point and therefore not marked with
 213    __THROW.  */
 214 extern int accept (int __fd, __SOCKADDR_ARG __addr,
 215                    socklen_t *__restrict __addr_len);
 216
 217 /* Shut down all or part of the connection open on socket FD.
 218    HOW determines what to shut down:
 219      SHUT_RD   = No more receptions;
 220      SHUT_WR   = No more transmissions;
 221      SHUT_RDWR = No more receptions or transmissions.
 222    Returns 0 on success, -1 for errors.  */
 223 extern int shutdown (int __fd, int __how) __THROW;
 224
 225
 226 #ifdef __USE_XOPEN2K
 227 /* Determine wheter socket is at a out-of-band mark.  */
 228 extern int sockatmark (int __fd) __THROW;
 229 #endif
 230
 231
 232 #ifdef __USE_MISC
 233 /* FDTYPE is S_IFSOCK or another S_IF* macro defined in <sys/stat.h>;
 234    returns 1 if FD is open on an object of the indicated type, 0 if not,
 235    or -1 for errors (setting errno).  */
 236 extern int isfdtype (int __fd, int __fdtype) __THROW;
 237 #endif
 238
 239
 240 /* Define some macros helping to catch buffer overflows.  */
 241 #if __USE_FORTIFY_LEVEL > 0 && defined __extern_always_inline
 242 # include <bits/socket2.h>
 243 #endif
 244
 245 __END_DECLS
 246
 247 #endif /* sys/socket.h */