xref: /illumos-gate/usr/src/lib/libsocket/socket/socketpair.c (revision e71ca95ca6de23d33b54cb55cefdef30bc7c969b)
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 _socket_create(int, int, int, int);
52 extern int _so_socketpair(int*);
53 
54 int _socketpair_create(int, int, int, int*, int);
55 
56 #pragma weak socketpair = _socketpair
57 
58 int
59 _socketpair(int family, int type, int protocol, int sv[2])
60 {
61 	return (_socketpair_create(family, type, protocol, sv, SOV_DEFAULT));
62 }
63 
64 /*
65  * Used by the BCP library.
66  */
67 int
68 _socketpair_bsd(int family, int type, int protocol, int sv[2])
69 {
70 	return (_socketpair_create(family, type, protocol, sv, SOV_SOCKBSD));
71 }
72 
73 int
74 _socketpair_svr4(int family, int type, int protocol, int sv[2])
75 {
76 	return (_socketpair_create(family, type, protocol, sv,
77 				SOV_SOCKSTREAM));
78 }
79 
80 int
81 __xnet_socketpair(int family, int type, int protocol, int sv[2])
82 {
83 	return (_socketpair_create(family, type, protocol, sv,
84 				SOV_XPG4_2));
85 }
86 
87 int
88 _socketpair_create(int family, int type, int protocol, int sv[2], int version)
89 {
90 	int res;
91 	int fd1, fd2;
92 
93 	/*
94 	 * Create the two sockets and pass them to _so_socketpair, which
95 	 * will connect them together.
96 	 */
97 	fd1 = _socket_create(family, type, protocol, version);
98 	if (fd1 < 0)
99 		return (-1);
100 	fd2 = _socket_create(family, type, protocol, version);
101 	if (fd2 < 0) {
102 		int error = errno;
103 
104 		(void) close(fd1);
105 		errno = error;
106 		return (-1);
107 	}
108 	sv[0] = fd1;
109 	sv[1] = fd2;
110 	res = _so_socketpair(sv);
111 	if (res < 0) {
112 		int error = errno;
113 
114 		(void) close(fd1);
115 		(void) close(fd2);
116 		errno = error;
117 		return (-1);
118 	}
119 	/*
120 	 * Check if kernel returned different fds in which case we close
121 	 * the original ones. This is the case for SOCK_STREAM where
122 	 * one of the original sockets is used as a listener and
123 	 * _so_socketpair passes out the newly accepted socket.
124 	 */
125 	if (sv[0] != fd1)
126 		(void) close(fd1);
127 	if (sv[1] != fd2)
128 		(void) close(fd2);
129 	return (res);
130 }
131