usr/src/lib/libc/port/socket/socketpair.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * University Copyright- Copyright (c) 1982, 1986, 1988
  32  * The Regents of the University of California
  33  * All Rights Reserved
  34  *
  35  * University Acknowledgment- Portions of this document are derived from
  36  * software developed by the University of California, Berkeley, and its
  37  * contributors.
  38  */
  39
  40 #pragma ident   "%Z%%M% %I%     %E% SMI"
  41
  42 #include <sys/types.h>
  43 #include <sys/socket.h>
  44 #include <sys/stropts.h>
  45 #include <sys/stream.h>
  46 #include <sys/socketvar.h>
  47 #include <errno.h>
  48 #include <unistd.h>
  49 #include <stdlib.h>
  50
  51 extern int _so_socketpair(int*);
  52
  53 #pragma weak __xnet_socketpair = socketpair
  54
  55 int
  56 socketpair(int family, int type, int protocol, int sv[2])
  57 {
  58         int res;
  59         int fd1, fd2;
  60
  61         /*
  62          * Create the two sockets and pass them to _so_socketpair, which
  63          * will connect them together.
  64          */
  65         fd1 = socket(family, type, protocol);
  66         if (fd1 < 0)
  67                 return (-1);
  68         fd2 = socket(family, type, protocol);
  69         if (fd2 < 0) {
  70                 int error = errno;
  71
  72                 (void) close(fd1);
  73                 errno = error;
  74                 return (-1);
  75         }
  76         sv[0] = fd1;
  77         sv[1] = fd2;
  78         res = _so_socketpair(sv);
  79         if (res < 0) {
  80                 int error = errno;
  81
  82                 (void) close(fd1);
  83                 (void) close(fd2);
  84                 errno = error;
  85                 return (-1);
  86         }
  87         /*
  88          * Check if kernel returned different fds in which case we close
  89          * the original ones. This is the case for SOCK_STREAM where
  90          * one of the original sockets is used as a listener and
  91          * _so_socketpair passes out the newly accepted socket.
  92          */
  93         if (sv[0] != fd1)
  94                 (void) close(fd1);
  95         if (sv[1] != fd2)
  96                 (void) close(fd2);
  97         return (res);
  98 }