1 /* $OpenLDAP: pkg/ldap/libraries/liblutil/sockpair.c,v 1.17.2.3 2008/02/11 23:26:42 kurt Exp $ */ 2 /* This work is part of OpenLDAP Software <http://www.openldap.org/>. 3 * 4 * Copyright 1998-2008 The OpenLDAP Foundation. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted only as authorized by the OpenLDAP 9 * Public License. 10 * 11 * A copy of this license is available in the file LICENSE in the 12 * top-level directory of the distribution or, alternatively, at 13 * <http://www.OpenLDAP.org/license.html>. 14 */ 15 16 #include "portable.h" 17 #include <ac/socket.h> 18 #include <ac/unistd.h> 19 20 #include <lutil.h> 21 22 /* Return a pair of socket descriptors that are connected to each other. 23 * The returned descriptors are suitable for use with select(). The two 24 * descriptors may or may not be identical; the function may return 25 * the same descriptor number in both slots. It is guaranteed that 26 * data written on sds[1] will be readable on sds[0]. The returned 27 * descriptors may be datagram oriented, so data should be written 28 * in reasonably small pieces and read all at once. On Unix systems 29 * this function is best implemented using a single pipe() call. 30 */ 31 32 int lutil_pair( ber_socket_t sds[2] ) 33 { 34 #ifdef USE_PIPE 35 return pipe( sds ); 36 #else 37 struct sockaddr_in si; 38 int rc; 39 ber_socklen_t len = sizeof(si); 40 ber_socket_t sd; 41 42 sd = socket( AF_INET, SOCK_DGRAM, 0 ); 43 if ( sd == AC_SOCKET_INVALID ) { 44 return sd; 45 } 46 47 (void) memset( (void*) &si, '\0', len ); 48 si.sin_family = AF_INET; 49 si.sin_port = 0; 50 si.sin_addr.s_addr = htonl( INADDR_LOOPBACK ); 51 52 rc = bind( sd, (struct sockaddr *)&si, len ); 53 if ( rc == AC_SOCKET_ERROR ) { 54 tcp_close(sd); 55 return rc; 56 } 57 58 rc = getsockname( sd, (struct sockaddr *)&si, &len ); 59 if ( rc == AC_SOCKET_ERROR ) { 60 tcp_close(sd); 61 return rc; 62 } 63 64 rc = connect( sd, (struct sockaddr *)&si, len ); 65 if ( rc == AC_SOCKET_ERROR ) { 66 tcp_close(sd); 67 return rc; 68 } 69 70 sds[0] = sd; 71 #if !HAVE_WINSOCK 72 sds[1] = dup( sds[0] ); 73 #else 74 sds[1] = sds[0]; 75 #endif 76 return 0; 77 #endif 78 } 79