socket/sys/socket.h

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