1 /* $NetBSD: signal.c,v 1.16 2024/01/03 18:41:53 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1985, 1989, 1993 5 * The Regents of the University of California. 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 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char sccsid[] = "@(#)signal.c 8.1 (Berkeley) 6/4/93"; 36 #else 37 __RCSID("$NetBSD: signal.c,v 1.16 2024/01/03 18:41:53 christos Exp $"); 38 #endif 39 #endif /* LIBC_SCCS and not lint */ 40 41 /* 42 * Almost backwards compatible signal. 43 */ 44 #include "namespace.h" 45 #include "extern.h" 46 #include <signal.h> 47 48 #ifdef __weak_alias 49 __weak_alias(signal,_signal) 50 #endif 51 52 sigset_t __sigintr; /* shared with siginterrupt */ 53 54 sig_t 55 signal(int s, sig_t a) 56 { 57 struct sigaction sa, osa; 58 59 sa.sa_handler = a; 60 sigemptyset(&sa.sa_mask); 61 sa.sa_flags = 0; 62 if (!sigismember(&__sigintr, s)) 63 sa.sa_flags |= SA_RESTART; 64 if (sigaction(s, &sa, &osa) < 0) 65 return (SIG_ERR); 66 return (osa.sa_handler); 67 } 68 69 void 70 (*bsd_signal(int sig, void (*func)(int)))(int) 71 { 72 struct sigaction act, oact; 73 74 act.sa_handler = func; 75 act.sa_flags = SA_RESTART; 76 77 sigemptyset(&act.sa_mask); 78 sigaddset(&act.sa_mask, sig); 79 if (sigaction(sig, &act, &oact) < 0) 80 return (SIG_ERR); 81 82 return (oact.sa_handler); 83 } 84