xref: /netbsd-src/external/bsd/openldap/dist/libraries/liblutil/sockpair.c (revision 549b59ed3ccf0d36d3097190a0db27b770f3a839)
1*549b59edSchristos /*	$NetBSD: sockpair.c,v 1.3 2021/08/14 16:14:58 christos Exp $	*/
24e6df137Slukem 
3d11b170bStron /* $OpenLDAP$ */
42de962bdSlukem /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
52de962bdSlukem  *
6*549b59edSchristos  * Copyright 1998-2021 The OpenLDAP Foundation.
72de962bdSlukem  * All rights reserved.
82de962bdSlukem  *
92de962bdSlukem  * Redistribution and use in source and binary forms, with or without
102de962bdSlukem  * modification, are permitted only as authorized by the OpenLDAP
112de962bdSlukem  * Public License.
122de962bdSlukem  *
132de962bdSlukem  * A copy of this license is available in the file LICENSE in the
142de962bdSlukem  * top-level directory of the distribution or, alternatively, at
152de962bdSlukem  * <http://www.OpenLDAP.org/license.html>.
162de962bdSlukem  */
172de962bdSlukem 
18376af7d7Schristos #include <sys/cdefs.h>
19*549b59edSchristos __RCSID("$NetBSD: sockpair.c,v 1.3 2021/08/14 16:14:58 christos Exp $");
20376af7d7Schristos 
212de962bdSlukem #include "portable.h"
222de962bdSlukem #include <ac/socket.h>
232de962bdSlukem #include <ac/unistd.h>
242de962bdSlukem 
252de962bdSlukem #include <lutil.h>
262de962bdSlukem 
272de962bdSlukem /* Return a pair of socket descriptors that are connected to each other.
282de962bdSlukem  * The returned descriptors are suitable for use with select(). The two
292de962bdSlukem  * descriptors may or may not be identical; the function may return
302de962bdSlukem  * the same descriptor number in both slots. It is guaranteed that
312de962bdSlukem  * data written on sds[1] will be readable on sds[0]. The returned
322de962bdSlukem  * descriptors may be datagram oriented, so data should be written
332de962bdSlukem  * in reasonably small pieces and read all at once. On Unix systems
342de962bdSlukem  * this function is best implemented using a single pipe() call.
352de962bdSlukem  */
362de962bdSlukem 
lutil_pair(ber_socket_t sds[2])372de962bdSlukem int lutil_pair( ber_socket_t sds[2] )
382de962bdSlukem {
392de962bdSlukem #ifdef USE_PIPE
402de962bdSlukem 	return pipe( sds );
412de962bdSlukem #else
422de962bdSlukem 	struct sockaddr_in si;
432de962bdSlukem 	int rc;
442de962bdSlukem 	ber_socklen_t len = sizeof(si);
452de962bdSlukem 	ber_socket_t sd;
462de962bdSlukem 
472de962bdSlukem 	sd = socket( AF_INET, SOCK_DGRAM, 0 );
482de962bdSlukem 	if ( sd == AC_SOCKET_INVALID ) {
492de962bdSlukem 		return sd;
502de962bdSlukem 	}
512de962bdSlukem 
522de962bdSlukem 	(void) memset( (void*) &si, '\0', len );
532de962bdSlukem 	si.sin_family = AF_INET;
542de962bdSlukem 	si.sin_port = 0;
552de962bdSlukem 	si.sin_addr.s_addr = htonl( INADDR_LOOPBACK );
562de962bdSlukem 
572de962bdSlukem 	rc = bind( sd, (struct sockaddr *)&si, len );
582de962bdSlukem 	if ( rc == AC_SOCKET_ERROR ) {
592de962bdSlukem 		tcp_close(sd);
602de962bdSlukem 		return rc;
612de962bdSlukem 	}
622de962bdSlukem 
632de962bdSlukem 	rc = getsockname( sd, (struct sockaddr *)&si, &len );
642de962bdSlukem 	if ( rc == AC_SOCKET_ERROR ) {
652de962bdSlukem 		tcp_close(sd);
662de962bdSlukem 		return rc;
672de962bdSlukem 	}
682de962bdSlukem 
692de962bdSlukem 	rc = connect( sd, (struct sockaddr *)&si, len );
702de962bdSlukem 	if ( rc == AC_SOCKET_ERROR ) {
712de962bdSlukem 		tcp_close(sd);
722de962bdSlukem 		return rc;
732de962bdSlukem 	}
742de962bdSlukem 
752de962bdSlukem 	sds[0] = sd;
762de962bdSlukem #if !HAVE_WINSOCK
772de962bdSlukem 	sds[1] = dup( sds[0] );
782de962bdSlukem #else
792de962bdSlukem 	sds[1] = sds[0];
802de962bdSlukem #endif
812de962bdSlukem 	return 0;
822de962bdSlukem #endif
832de962bdSlukem }
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