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 1.7 1997/06/09 03:27:36 brian Exp $ 30 * 31 * TODO: 32 * 33 */ 34 35 #include "sig.h" 36 #include <sys/types.h> 37 #include <signal.h> 38 #include "mbuf.h" 39 #include "log.h" 40 41 static caused[NSIG]; /* An array of pending signals */ 42 static sig_type handler[NSIG]; /* all start at SIG_DFL */ 43 44 45 /* Record a signal in the "caused" array */ 46 47 static void 48 signal_recorder(int sig) 49 { 50 caused[sig - 1]++; 51 } 52 53 54 /* 55 * Set up signal_recorder, and record handler as the function to ultimately 56 * call in handle_signal() 57 */ 58 59 sig_type 60 pending_signal(int sig, sig_type fn) 61 { 62 sig_type Result; 63 64 if (sig <= 0 || sig > NSIG) { 65 /* Oops - we must be a bit out of date (too many sigs ?) */ 66 LogPrintf(LogALERT, "Eeek! %s:%s: I must be out of date!\n", 67 __FILE__, __LINE__); 68 return signal(sig, fn); 69 } 70 Result = handler[sig - 1]; 71 if (fn == SIG_DFL || fn == SIG_IGN) { 72 signal(sig, fn); 73 handler[sig - 1] = (sig_type) 0; 74 } else { 75 handler[sig - 1] = fn; 76 signal(sig, signal_recorder); 77 } 78 caused[sig - 1] = 0; 79 return Result; 80 } 81 82 83 /* Call the handlers for any pending signals */ 84 85 void 86 handle_signals() 87 { 88 int sig; 89 int got; 90 91 do { 92 got = 0; 93 for (sig = 0; sig < NSIG; sig++) 94 if (caused[sig]) { 95 caused[sig]--; 96 got++; 97 (*handler[sig]) (sig + 1); 98 } 99 } while (got); 100 } 101