xref: /illumos-gate/usr/src/lib/libsocket/socket/socketpair.c (revision 9b9d39d2a32ff806d2431dbcc50968ef1e6d46b2)
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 #include <sys/types.h>
41 #include <sys/socket.h>
42 #include <sys/stropts.h>
43 #include <sys/stream.h>
44 #include <sys/socketvar.h>
45 #include <errno.h>
46 #include <unistd.h>
47 #include <stdlib.h>
48 
49 extern int _socket_create(int, int, int, int);
50 extern int _so_socketpair(int *);
51 
52 int _socketpair_create(int, int, int, int [2], int);
53 
54 #pragma weak socketpair = _socketpair
55 
56 int
57 _socketpair(int family, int type, int protocol, int sv[2])
58 {
59 	return (_socketpair_create(family, type, protocol, sv, SOV_DEFAULT));
60 }
61 
62 /*
63  * Used by the BCP library.
64  */
65 int
66 _socketpair_bsd(int family, int type, int protocol, int sv[2])
67 {
68 	return (_socketpair_create(family, type, protocol, sv, SOV_SOCKBSD));
69 }
70 
71 int
72 _socketpair_svr4(int family, int type, int protocol, int sv[2])
73 {
74 	return (_socketpair_create(family, type, protocol, sv, SOV_SOCKSTREAM));
75 }
76 
77 int
78 __xnet_socketpair(int family, int type, int protocol, int sv[2])
79 {
80 	return (_socketpair_create(family, type, protocol, sv, SOV_XPG4_2));
81 }
82 
83 int
84 _socketpair_create(int family, int type, int protocol, int sv[2], int version)
85 {
86 	int res;
87 	int fd1, fd2;
88 
89 	/*
90 	 * Create the two sockets and pass them to _so_socketpair, which
91 	 * will connect them together.
92 	 */
93 	fd1 = _socket_create(family, type, protocol, version);
94 	if (fd1 < 0)
95 		return (-1);
96 	fd2 = _socket_create(family, type, protocol, version);
97 	if (fd2 < 0) {
98 		int error = errno;
99 
100 		(void) close(fd1);
101 		errno = error;
102 		return (-1);
103 	}
104 	sv[0] = fd1;
105 	sv[1] = fd2;
106 	res = _so_socketpair(sv);
107 	if (res < 0) {
108 		int error = errno;
109 
110 		(void) close(fd1);
111 		(void) close(fd2);
112 		errno = error;
113 		return (-1);
114 	}
115 	/*
116 	 * Check if kernel returned different fds in which case we close
117 	 * the original ones. This is the case for SOCK_STREAM where
118 	 * one of the original sockets is used as a listener and
119 	 * _so_socketpair passes out the newly accepted socket.
120 	 */
121 	if (sv[0] != fd1)
122 		(void) close(fd1);
123 	if (sv[1] != fd2)
124 		(void) close(fd2);
125 	return (res);
126 }
127