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/* Signal handling routines. |
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* |
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* IRC Services is copyright (c) 1996-2009 Andrew Church. |
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* E-mail: <achurch@achurch.org> |
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* Parts written by Andrew Kempe and others. |
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* This program is free but copyrighted software; see the file GPL.txt for |
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* details. |
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*/ |
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|
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#include "services.h" |
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#include <setjmp.h> |
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|
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/*************************************************************************/ |
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|
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/* If we get a signal, use this to jump out of the main loop. */ |
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static sigjmp_buf *panic_ptr = NULL; |
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|
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/*************************************************************************/ |
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/*************************************************************************/ |
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|
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/* Various signal handlers. */ |
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|
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/*************************************************************************/ |
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|
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/* SIGHUP = save databases and rehash configuration files */ |
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static void |
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sighup_handler(int sig_unused) |
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{ |
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signal(SIGHUP, SIG_IGN); /* in case we get double signalled */ |
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log("Received SIGHUP, saving data and rehashing."); |
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wallops(NULL, |
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"Received SIGHUP, saving data and rehashing configuration files"); |
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save_data_now(); |
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reconfigure(); |
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signal(SIGHUP, sighup_handler); |
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} |
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|
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/*************************************************************************/ |
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|
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/* SIGTERM = save databases and shut down */ |
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static void |
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sigterm_handler(int sig_unused) |
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{ |
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save_data = 1; |
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delayed_quit = 1; |
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signal(SIGTERM, SIG_IGN); |
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signal(SIGHUP, SIG_IGN); |
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log("Received SIGTERM, exiting."); |
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strbcpy(quitmsg, "Shutting down on SIGTERM"); |
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siglongjmp(*panic_ptr, 1); |
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} |
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|
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/*************************************************************************/ |
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|
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/* SIGUSR2 = close and reopen log file */ |
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static void |
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sigusr2_handler(int sig_unused) |
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{ |
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log("Received SIGUSR2, cycling log file."); |
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if (log_is_open()) |
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{ |
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close_log(); |
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open_log(); |
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} |
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signal(SIGUSR2, sigusr2_handler); |
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} |
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|
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/*************************************************************************/ |
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|
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/* If we get a weird signal, come here. */ |
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static void |
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weirdsig_handler(int signum) |
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{ |
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static int dying = 0; /* Flag to avoid infinite recursion */ |
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|
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if (dying++) |
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{ |
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/* Double signal, give up. Set `servsock' to NULL to avoid a |
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* message going out that way, just in case the socket code is |
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* confused/broken */ |
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servsock = NULL; |
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if (signum == SIGUSR2) |
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{ |
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fatal("Out of memory while shutting down"); |
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} |
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else |
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{ |
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#if HAVE_STRSIGNAL |
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fatal("Caught signal %d (%s) while shutting down", signum, |
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strsignal(signum)); |
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#else |
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fatal("Caught signal %d while shutting down", signum); |
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#endif |
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} |
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} |
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|
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/* Avoid spurious keyboard signals killing us while shutting down */ |
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signal(SIGINT, SIG_IGN); |
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signal(SIGQUIT, SIG_IGN); |
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signal(SIGTSTP, SIG_IGN); |
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|
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/* If we died processing a message, let people know about it */ |
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if (signum != SIGINT && signum != SIGQUIT) |
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{ |
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if (*inbuf) |
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{ |
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log("PANIC! signal %d, buffer = %s", signum, inbuf); |
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/* Cut off if this would make IRC command >510 characters. */ |
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if (strlen(inbuf) > 448) |
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{ |
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inbuf[446] = '>'; |
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inbuf[447] = '>'; |
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inbuf[448] = 0; |
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} |
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wallops(NULL, "PANIC! buffer = %s\r\n", inbuf); |
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} |
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else |
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{ |
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log("PANIC! signal %d (no buffer)", signum); |
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wallops(NULL, "PANIC! signal %d (no buffer)", signum); |
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} |
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} |
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|
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/* Pick an appropriate quit message */ |
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if (signum == SIGUSR1) |
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{ |
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strbcpy(quitmsg, "Out of memory!"); |
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quitting = 1; |
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} |
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else |
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{ |
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#if HAVE_STRSIGNAL |
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snprintf(quitmsg, sizeof(quitmsg), |
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"Services terminating: %s", strsignal(signum)); |
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#else |
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snprintf(quitmsg, sizeof(quitmsg), |
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"Services terminating on signal %d", signum); |
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#endif |
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quitting = 1; |
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} |
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|
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/* Actually quit */ |
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if (panic_ptr) |
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{ |
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siglongjmp(*panic_ptr, 1); |
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} |
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else |
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{ |
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log("%s", quitmsg); |
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if (isatty(2)) |
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fprintf(stderr, "%s\n", quitmsg); |
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exit(1); |
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} |
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} |
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|
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/*************************************************************************/ |
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/*************************************************************************/ |
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|
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/* Set up signal handlers. Catch certain signals to let us do things or |
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* panic as necessary, and ignore all others. |
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*/ |
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|
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void |
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init_signals(void) |
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{ |
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int i; |
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|
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/* Start out with special signals disabled */ |
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disable_signals(); |
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|
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/* Set all signals to "ignore" */ |
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for (i = 1; i <= NSIG; i++) |
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{ |
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#if DUMPCORE |
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if (i != SIGSEGV) |
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#endif |
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if (i != SIGPROF && i != SIGCHLD) |
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signal(i, SIG_IGN); |
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} |
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|
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/* Specify particular signals we want to catch */ |
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|
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/* Signals that probably mean bad things have happened */ |
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#if !DUMPCORE |
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signal(SIGSEGV, weirdsig_handler); |
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#endif |
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signal(SIGBUS, weirdsig_handler); |
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signal(SIGILL, weirdsig_handler); |
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signal(SIGTRAP, weirdsig_handler); |
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signal(SIGFPE, weirdsig_handler); |
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#ifdef SIGIOT |
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signal(SIGIOT, weirdsig_handler); |
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#endif |
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|
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/* This is our "out-of-memory" panic switch */ |
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signal(SIGUSR1, weirdsig_handler); |
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|
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/* Other special handlers */ |
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signal(SIGTERM, sigterm_handler); |
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signal(SIGINT, weirdsig_handler); |
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signal(SIGQUIT, weirdsig_handler); |
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signal(SIGHUP, sighup_handler); |
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signal(SIGUSR2, sigusr2_handler); |
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|
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} |
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|
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/*************************************************************************/ |
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|
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/* Helper routine for main.c's DO_SIGSETJMP() macro; saves a pointer to the |
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* environment buffer locally. |
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*/ |
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|
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void |
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do_sigsetjmp(void *bufptr) |
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{ |
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panic_ptr = bufptr; |
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} |
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|
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/*************************************************************************/ |
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|
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/* Enable or disable receipt of certain signals (in particular, those which |
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* cause us to take actions other than simply terminating the program, to |
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* avoid such signals happening at inopportune times and causing things to |
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* break). |
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*/ |
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|
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void |
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enable_signals(void) |
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{ |
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sigset_t sigs; |
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sigemptyset(&sigs); |
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sigaddset(&sigs, SIGHUP); |
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sigaddset(&sigs, SIGTERM); |
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sigaddset(&sigs, SIGUSR2); |
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sigprocmask(SIG_UNBLOCK, &sigs, NULL); |
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} |
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|
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|
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void |
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disable_signals(void) |
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{ |
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sigset_t sigs; |
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sigemptyset(&sigs); |
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sigaddset(&sigs, SIGHUP); |
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sigaddset(&sigs, SIGTERM); |
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sigaddset(&sigs, SIGUSR2); |
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sigprocmask(SIG_BLOCK, &sigs, NULL); |
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} |
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|
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/*************************************************************************/ |
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|
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/* |
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* Local variables: |
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* c-file-style: "stroustrup" |
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* c-file-offsets: ((case-label . *) (statement-case-intro . *)) |
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* indent-tabs-mode: nil |
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* End: |
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* |
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* vim: expandtab shiftwidth=4: |
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*/ |
