socket/sys/socket.h

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