adtools/clib2

/*
 * $Id: signal_raise.c,v 1.10 2006-01-08 12:04:24 obarthel Exp $
 *
 * :ts=4
 *
 * Portable ISO 'C' (1994) runtime library for the Amiga computer
 * Copyright (c) 2002-2015 by Olaf Barthel <obarthel (at) gmx.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Neither the name of Olaf Barthel nor the names of contributors
 *     may be used to endorse or promote products derived from this
 *     software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _SIGNAL_HEADERS_H
#include "signal_headers.h"
#endif /* _SIGNAL_HEADERS_H */

/****************************************************************************/

/* This table holds pointers to all signal handlers configured at a time. */
signal_handler_t NOCOMMON __signal_handler_table[NUM_SIGNALS] =
{
    SIG_DFL,    /* SIGABRT */
    SIG_DFL,    /* SIGFPE */
    SIG_DFL,    /* SIGILL */
    SIG_DFL,    /* SIGINT */
    SIG_DFL,    /* SIGSEGV */
    SIG_DFL        /* SIGTERM */
};

/****************************************************************************/

/* This holds a mask of all signals whose delivery is currently blocked.
   The sigaddset(), sigblock(), sigprocmask() and sigsetmask() functions
   modify or query it. */
int NOCOMMON __signals_blocked;

/****************************************************************************/

int
raise(int sig)
{
    static int local_signals_blocked;

    int result = ERROR;

    ENTER();

    SHOWVALUE(sig);

    assert( SIGABRT <= sig && sig <= SIGTERM );

    /* This has to be a well-known and supported signal. */
    if(sig < SIGABRT || sig > SIGTERM)
    {
        SHOWMSG("unknown signal number");

        __set_errno(EINVAL);
        goto out;
    }

    /* Can we deliver the signal? */
    if(FLAG_IS_CLEAR(__signals_blocked,        (1 << sig)) &&
       FLAG_IS_CLEAR(local_signals_blocked,    (1 << sig)))
    {
        signal_handler_t handler;

        /* Which handler is installed for this signal? */
        handler = __signal_handler_table[sig - SIGABRT];

        /* Should we ignore this signal? */
        if(handler != SIG_IGN)
        {
            /* Block delivery of this signal to prevent recursion. */
            SET_FLAG(local_signals_blocked,(1 << sig));

            /* The default behaviour is to drop into abort(), or do
               something very much like it. */
            if(handler == SIG_DFL)
            {
                SHOWMSG("this is the default handler");

                if(sig == SIGINT)
                {
                    char break_string[80];

                    /* Turn off ^C checking for good. */
                    __check_abort_enabled = FALSE;

                    Fault(ERROR_BREAK,NULL,break_string,(LONG)sizeof(break_string));

                    __print_termination_message(break_string);

                    SHOWMSG("bye, bye...");
                }

                /* Drop straight into abort(), which might call signal()
                   again but is otherwise guaranteed to eventually
                   land us in _exit(). */
                abort();
            }
            else 
            {
                SHOWMSG("calling the handler");

                (*handler)(sig);

                SHOWMSG("done.");
            }

            /* Unblock signal delivery again. */
            CLEAR_FLAG(local_signals_blocked,(1 << sig));
        }
    }
    else
    {
        SHOWMSG("that signal is blocked");
    }

    result = OK;

 out:

    RETURN(result);
    return(result);
}