usr/src/lib/libc/port/socket/socket.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 (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
  23  */
  24
  25 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  26 /*        All Rights Reserved   */
  27
  28 /*
  29  * University Copyright- Copyright (c) 1982, 1986, 1988
  30  * The Regents of the University of California
  31  * All Rights Reserved
  32  *
  33  * University Acknowledgment- Portions of this document are derived from
  34  * software developed by the University of California, Berkeley, and its
  35  * contributors.
  36  */
  37
  38 #include <sys/types.h>
  39 #include <sys/socket.h>
  40 #include <sys/stropts.h>
  41 #include <sys/stream.h>
  42 #include <sys/socketvar.h>
  43 #include <errno.h>
  44 #include <unistd.h>
  45 #include <stdlib.h>
  46
  47 extern int _so_socket();
  48 extern int _s_netconfig_path();
  49
  50 #pragma weak __xnet_socket = socket
  51
  52 int
  53 socket(int family, int type, int protocol)
  54 {
  55         int fd;
  56
  57         /*
  58          * Try creating without knowing the device assuming that
  59          * the transport provider is registered in /etc/sock2path.d.
  60          * If none found fall back to using /etc/netconfig to look
  61          * up the name of the transport device name. This provides
  62          * backwards compatibility for transport providers that have not
  63          * yet been converted to using /etc/sock2path.d.
  64          * XXX When all transport providers use /etc/sock2path.d. this
  65          * part of the code can be removed.
  66          */
  67         fd = _so_socket(family, type, protocol, NULL);
  68         if (fd == -1) {
  69                 char *devpath;
  70                 int saved_errno = errno;
  71                 int prototype = 0;
  72
  73                 switch (saved_errno) {
  74                 case EAFNOSUPPORT:
  75                 case EPROTOTYPE:
  76                         break;
  77                 case EPROTONOSUPPORT:
  78                         break;
  79
  80                 default:
  81                         errno = saved_errno;
  82                         return (-1);
  83                 }
  84                 if (_s_netconfig_path(family, type, protocol,
  85                     &devpath, &prototype) == -1) {
  86                         errno = saved_errno;
  87                         return (-1);
  88                 }
  89                 fd = _so_socket(family, type, protocol, devpath);
  90                 free(devpath);
  91                 if (fd == -1) {
  92                         errno = saved_errno;
  93                         return (-1);
  94                 }
  95                 if (prototype != 0) {
  96                         if (setsockopt(fd, SOL_SOCKET, SO_PROTOTYPE,
  97                             (caddr_t)&prototype, (int)sizeof (prototype)) < 0) {
  98                                 (void) close(fd);
  99                                 /*
 100                                  * setsockopt often fails with ENOPROTOOPT
 101                                  * but socket() should fail with
 102                                  * EPROTONOSUPPORT.
 103                                  */
 104                                 errno = EPROTONOSUPPORT;
 105                                 return (-1);
 106                         }
 107                 }
 108         }
 109         return (fd);
 110 }