socket/sys/socket.h

   1 /* Declarations of socket constants, types, and functions.
   2    Copyright (C) 1991-2014 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_BSD
  41 /* This is the 4.3 BSD `struct sockaddr' format, which is used as wire
  42    format in the grotty old 4.3 `talk' protocol.  */
  43 struct osockaddr
  44   {
  45     unsigned short int sa_family;
  46     unsigned char sa_data[14];
  47   };
  48 #endif
  49
  50 /* The following constants should be used for the second parameter of
  51    `shutdown'.  */
  52 enum
  53 {
  54   SHUT_RD = 0,          /* No more receptions.  */
  55 #define SHUT_RD         SHUT_RD
  56   SHUT_WR,              /* No more transmissions.  */
  57 #define SHUT_WR         SHUT_WR
  58   SHUT_RDWR             /* No more receptions or transmissions.  */
  59 #define SHUT_RDWR       SHUT_RDWR
  60 };
  61
  62 /* This is the type we use for generic socket address arguments.
  63
  64    With GCC 2.7 and later, the funky union causes redeclarations or
  65    uses with any of the listed types to be allowed without complaint.
  66    G++ 2.7 does not support transparent unions so there we want the
  67    old-style declaration, too.  */
  68 #if defined __cplusplus || !__GNUC_PREREQ (2, 7) || !defined __USE_GNU
  69 # define __SOCKADDR_ARG         struct sockaddr *__restrict
  70 # define __CONST_SOCKADDR_ARG   const struct sockaddr *
  71 #else
  72 /* Add more `struct sockaddr_AF' types here as necessary.
  73    These are all the ones I found on NetBSD and Linux.  */
  74 # define __SOCKADDR_ALLTYPES \
  75   __SOCKADDR_ONETYPE (sockaddr) \
  76   __SOCKADDR_ONETYPE (sockaddr_at) \
  77   __SOCKADDR_ONETYPE (sockaddr_ax25) \
  78   __SOCKADDR_ONETYPE (sockaddr_dl) \
  79   __SOCKADDR_ONETYPE (sockaddr_eon) \
  80   __SOCKADDR_ONETYPE (sockaddr_in) \
  81   __SOCKADDR_ONETYPE (sockaddr_in6) \
  82   __SOCKADDR_ONETYPE (sockaddr_inarp) \
  83   __SOCKADDR_ONETYPE (sockaddr_ipx) \
  84   __SOCKADDR_ONETYPE (sockaddr_iso) \
  85   __SOCKADDR_ONETYPE (sockaddr_ns) \
  86   __SOCKADDR_ONETYPE (sockaddr_un) \
  87   __SOCKADDR_ONETYPE (sockaddr_x25)
  88
  89 # define __SOCKADDR_ONETYPE(type) struct type *__restrict __##type##__;
  90 typedef union { __SOCKADDR_ALLTYPES
  91               } __SOCKADDR_ARG __attribute__ ((__transparent_union__));
  92 # undef __SOCKADDR_ONETYPE
  93 # define __SOCKADDR_ONETYPE(type) const struct type *__restrict __##type##__;
  94 typedef union { __SOCKADDR_ALLTYPES
  95               } __CONST_SOCKADDR_ARG __attribute__ ((__transparent_union__));
  96 # undef __SOCKADDR_ONETYPE
  97 #endif
  98
  99 #ifdef __USE_GNU
 100 /* For `recvmmsg' and `sendmmsg'.  */
 101 struct mmsghdr
 102   {
 103     struct msghdr msg_hdr;      /* Actual message header.  */
 104     unsigned int msg_len;       /* Number of received or sent bytes for the
 105                                    entry.  */
 106   };
 107 #endif
 108
 109
 110 /* Create a new socket of type TYPE in domain DOMAIN, using
 111    protocol PROTOCOL.  If PROTOCOL is zero, one is chosen automatically.
 112    Returns a file descriptor for the new socket, or -1 for errors.  */
 113 extern int socket (int __domain, int __type, int __protocol) __THROW;
 114
 115 /* Create two new sockets, of type TYPE in domain DOMAIN and using
 116    protocol PROTOCOL, which are connected to each other, and put file
 117    descriptors for them in FDS[0] and FDS[1].  If PROTOCOL is zero,
 118    one will be chosen automatically.  Returns 0 on success, -1 for errors.  */
 119 extern int socketpair (int __domain, int __type, int __protocol,
 120                        int __fds[2]) __THROW;
 121
 122 /* Give the socket FD the local address ADDR (which is LEN bytes long).  */
 123 extern int bind (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len)
 124      __THROW;
 125
 126 /* Put the local address of FD into *ADDR and its length in *LEN.  */
 127 extern int getsockname (int __fd, __SOCKADDR_ARG __addr,
 128                         socklen_t *__restrict __len) __THROW;
 129
 130 /* Open a connection on socket FD to peer at ADDR (which LEN bytes long).
 131    For connectionless socket types, just set the default address to send to
 132    and the only address from which to accept transmissions.
 133    Return 0 on success, -1 for errors.
 134
 135    This function is a cancellation point and therefore not marked with
 136    __THROW.  */
 137 extern int connect (int __fd, __CONST_SOCKADDR_ARG __addr, socklen_t __len);
 138
 139 /* Put the address of the peer connected to socket FD into *ADDR
 140    (which is *LEN bytes long), and its actual length into *LEN.  */
 141 extern int getpeername (int __fd, __SOCKADDR_ARG __addr,
 142                         socklen_t *__restrict __len) __THROW;
 143
 144
 145 /* Send N bytes of BUF to socket FD.  Returns the number sent or -1.
 146
 147    This function is a cancellation point and therefore not marked with
 148    __THROW.  */
 149 extern ssize_t send (int __fd, const void *__buf, size_t __n, int __flags);
 150
 151 /* Read N bytes into BUF from socket FD.
 152    Returns the number read or -1 for errors.
 153
 154    This function is a cancellation point and therefore not marked with
 155    __THROW.  */
 156 extern ssize_t recv (int __fd, void *__buf, size_t __n, int __flags);
 157
 158 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is
 159    ADDR_LEN bytes long).  Returns the number sent, or -1 for errors.
 160
 161    This function is a cancellation point and therefore not marked with
 162    __THROW.  */
 163 extern ssize_t sendto (int __fd, const void *__buf, size_t __n,
 164                        int __flags, __CONST_SOCKADDR_ARG __addr,
 165                        socklen_t __addr_len);
 166
 167 /* Read N bytes into BUF through socket FD.
 168    If ADDR is not NULL, fill in *ADDR_LEN bytes of it with tha address of
 169    the sender, and store the actual size of the address in *ADDR_LEN.
 170    Returns the number of bytes read or -1 for errors.
 171
 172    This function is a cancellation point and therefore not marked with
 173    __THROW.  */
 174 extern ssize_t recvfrom (int __fd, void *__restrict __buf, size_t __n,
 175                          int __flags, __SOCKADDR_ARG __addr,
 176                          socklen_t *__restrict __addr_len);
 177
 178
 179 /* Send a message described MESSAGE on socket FD.
 180    Returns the number of bytes sent, or -1 for errors.
 181
 182    This function is a cancellation point and therefore not marked with
 183    __THROW.  */
 184 extern ssize_t sendmsg (int __fd, const struct msghdr *__message,
 185                         int __flags);
 186
 187 #ifdef __USE_GNU
 188 /* Send a VLEN messages as described by VMESSAGES to socket FD.
 189    Returns the number of datagrams successfully written or -1 for errors.
 190
 191    This function is a cancellation point and therefore not marked with
 192    __THROW.  */
 193 extern int sendmmsg (int __fd, struct mmsghdr *__vmessages,
 194                      unsigned int __vlen, int __flags);
 195 #endif
 196
 197 /* Receive a message as described by MESSAGE from socket FD.
 198    Returns the number of bytes read or -1 for errors.
 199
 200    This function is a cancellation point and therefore not marked with
 201    __THROW.  */
 202 extern ssize_t recvmsg (int __fd, struct msghdr *__message, int __flags);
 203
 204 #ifdef __USE_GNU
 205 /* Receive up to VLEN messages as described by VMESSAGES from socket FD.
 206    Returns the number of bytes read or -1 for errors.
 207
 208    This function is a cancellation point and therefore not marked with
 209    __THROW.  */
 210 extern int recvmmsg (int __fd, struct mmsghdr *__vmessages,
 211                      unsigned int __vlen, int __flags,
 212                      const struct timespec *__tmo);
 213 #endif
 214
 215
 216 /* Put the current value for socket FD's option OPTNAME at protocol level LEVEL
 217    into OPTVAL (which is *OPTLEN bytes long), and set *OPTLEN to the value's
 218    actual length.  Returns 0 on success, -1 for errors.  */
 219 extern int getsockopt (int __fd, int __level, int __optname,
 220                        void *__restrict __optval,
 221                        socklen_t *__restrict __optlen) __THROW;
 222
 223 /* Set socket FD's option OPTNAME at protocol level LEVEL
 224    to *OPTVAL (which is OPTLEN bytes long).
 225    Returns 0 on success, -1 for errors.  */
 226 extern int setsockopt (int __fd, int __level, int __optname,
 227                        const void *__optval, socklen_t __optlen) __THROW;
 228
 229
 230 /* Prepare to accept connections on socket FD.
 231    N connection requests will be queued before further requests are refused.
 232    Returns 0 on success, -1 for errors.  */
 233 extern int listen (int __fd, int __n) __THROW;
 234
 235 /* Await a connection on socket FD.
 236    When a connection arrives, open a new socket to communicate with it,
 237    set *ADDR (which is *ADDR_LEN bytes long) to the address of the connecting
 238    peer and *ADDR_LEN to the address's actual length, and return the
 239    new socket's descriptor, or -1 for errors.
 240
 241    This function is a cancellation point and therefore not marked with
 242    __THROW.  */
 243 extern int accept (int __fd, __SOCKADDR_ARG __addr,
 244                    socklen_t *__restrict __addr_len);
 245
 246 #ifdef __USE_GNU
 247 /* Similar to 'accept' but takes an additional parameter to specify flags.
 248
 249    This function is a cancellation point and therefore not marked with
 250    __THROW.  */
 251 extern int accept4 (int __fd, __SOCKADDR_ARG __addr,
 252                     socklen_t *__restrict __addr_len, int __flags);
 253 #endif
 254
 255 /* Shut down all or part of the connection open on socket FD.
 256    HOW determines what to shut down:
 257      SHUT_RD   = No more receptions;
 258      SHUT_WR   = No more transmissions;
 259      SHUT_RDWR = No more receptions or transmissions.
 260    Returns 0 on success, -1 for errors.  */
 261 extern int shutdown (int __fd, int __how) __THROW;
 262
 263
 264 #ifdef __USE_XOPEN2K
 265 /* Determine wheter socket is at a out-of-band mark.  */
 266 extern int sockatmark (int __fd) __THROW;
 267 #endif
 268
 269
 270 #ifdef __USE_MISC
 271 /* FDTYPE is S_IFSOCK or another S_IF* macro defined in <sys/stat.h>;
 272    returns 1 if FD is open on an object of the indicated type, 0 if not,
 273    or -1 for errors (setting errno).  */
 274 extern int isfdtype (int __fd, int __fdtype) __THROW;
 275 #endif
 276
 277
 278 /* Define some macros helping to catch buffer overflows.  */
 279 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
 280 # include <bits/socket2.h>
 281 #endif
 282
 283 __END_DECLS
 284
 285 #endif /* sys/socket.h */