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      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 */
    244