1 /*- 2 * Copyright (c) 1997 3 * Brian Somers <brian@awfulhak.demon.co.uk>. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $Id: sig.c,v 1.4 1997/02/25 14:05:10 brian Exp $ 30 * 31 * TODO: 32 * 33 */ 34 35 #include <sys/cdefs.h> 36 #include "sig.h" 37 #include <sys/types.h> 38 #include <signal.h> 39 #include "mbuf.h" 40 #include "log.h" 41 42 static caused[NSIG]; /* An array of pending signals */ 43 static sig_type handler[NSIG]; /* all start at SIG_DFL */ 44 45 46 /* Record a signal in the "caused" array */ 47 48 static void signal_recorder(int sig) { 49 caused[sig-1]++; 50 } 51 52 53 /* 54 set up signal_recorder, and record handler as the function to ultimately 55 call in handle_signal() 56 */ 57 58 sig_type pending_signal(int sig,sig_type fn) { 59 sig_type Result; 60 61 if (sig <= 0 || sig > NSIG) { 62 /* Oops - we must be a bit out of date (too many sigs ?) */ 63 logprintf("Eeek! %s:%s: I must be out of date!\n",__FILE__,__LINE__); 64 return signal(sig,fn); 65 } 66 67 Result = handler[sig-1]; 68 if (fn == SIG_DFL || fn == SIG_IGN) { 69 signal(sig,fn); 70 handler[sig-1] = (sig_type)0; 71 } else { 72 handler[sig-1] = fn; 73 signal(sig,signal_recorder); 74 } 75 caused[sig-1] = 0; 76 return Result; 77 } 78 79 80 /* Call the handlers for any pending signals */ 81 82 void handle_signals() { 83 int sig; 84 int got; 85 86 do { 87 got = 0; 88 for (sig = 0; sig < NSIG; sig++) 89 if (caused[sig]) { 90 caused[sig]--; 91 got++; 92 (*handler[sig])(sig+1); 93 } 94 } while(got); 95 } 96