1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1998 Brian Somers <brian@Awfulhak.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/time.h> 30 #include <sys/socket.h> 31 32 #include <stdio.h> 33 #include <unistd.h> 34 35 #include "probe.h" 36 #include "log.h" 37 #include "id.h" 38 39 struct probe probe; 40 41 /* Does select() alter the passed time value ? */ 42 static int 43 select_changes_time(void) 44 { 45 struct timeval t; 46 47 t.tv_sec = 0; 48 t.tv_usec = 100000; 49 select(0, NULL, NULL, NULL, &t); 50 return t.tv_usec != 100000; 51 } 52 53 #ifndef NOINET6 54 static int 55 ipv6_available(void) 56 { 57 int s; 58 59 if ((s = ID0socket(PF_INET6, SOCK_DGRAM, 0)) == -1) 60 return 0; 61 62 close(s); 63 return 1; 64 } 65 #endif 66 67 void 68 probe_Init(void) 69 { 70 probe.select_changes_time = select_changes_time() ? 1 : 0; 71 log_Printf(LogDEBUG, "Select changes time: %s\n", 72 probe.select_changes_time ? "yes" : "no"); 73 #ifndef NOINET6 74 probe.ipv6_available = ipv6_available() ? 1 : 0; 75 log_Printf(LogDEBUG, "IPv6 available: %s\n", 76 probe.ipv6_available ? "yes" : "no"); 77 #endif 78 } 79