sig.c

/***************************************************************************
 * CVSID: $Id: sig.c,v 1.3 2004/08/07 15:10:47 stefanb Exp $
 *
 * sig.c : Functions for signal handling
 *
 * Copyright (C) 2004 Stefan Bambach, <sbambach@gmx.net>
 *
 * Licensed under the GNU General Public License 2.0
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 **************************************************************************/
 
#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <stdio.h>
#include <signal.h>

#include "sig.h"
#include "dbug_mem.h"



sb_signal_handler_t sb_signal_handler[MAX_SIGNALS];



int
sb_signal_init(void)
{
    int i=0;
    
    for (i=0; i<MAX_SIGNALS; i++) {
        sb_signal_handler[i] = SIG_DFL;
    }
    
    return 0;
}



int
sb_signal_is_initialized(void)
{
    static int initialized = 0;
    
    if (initialized == 0) {
        if (sb_signal_init() == 0) {
            initialized = 1;
        }
    }
    
    return initialized;
}



int
sb_signal_set_handler(int signum, sb_signal_handler_t handler)
{
    sb_signal_handler_t old_handler = SIG_DFL;
    
    if (sb_signal_is_initialized() == 0) {
        return -1;
    }

    if (sb_signal_handler[signum] == SIG_DFL) {
        old_handler = signal(signum, handler);
        if (old_handler != SIG_ERR) {
            sb_signal_handler[signum] = old_handler;
            return 0;
        }
    }
    
    return -1;
}
 


int
sb_signal_restore_handler(int signum)
{
    if (sb_signal_is_initialized() == 0) {
        return -1;
    }

    if (sb_signal_handler[signum] != SIG_DFL) {
        if (signal(signum, sb_signal_handler[signum]) == SIG_ERR) {
            return -1;
        }
    }
    
    return 0;
}
 


int
sb_signal_restore_all_handlers(void)
{
    int signum=0;
    int error=0;
    
    if (sb_signal_is_initialized() == 0) {
        return -1;
    }

    for (signum=0; signum<MAX_SIGNALS; signum++) {
        if (sb_signal_restore_handler(signum) != 0) {
            error++;
        }
    }
    
    if (error > 0) {
        return -1;
    }
    
    return 0;
}

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