/*
 * Copyright (c) 1995, 1996 Gunther Schadow.  All rights reserved.
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "pg_config.h"

IDENT("@(#) trap.c (Gunther Schadow) 12/19/96");

#include "trap.h"
#include <signal.h>
#include <stdio.h>
#include <syslog.h>

volatile bool israised[NSIG];
jmp_buf __signal_jmp[NSIG];

void
__jsignal(int sig)
{
  israised[sig] = TRUE;
  DBG(syslog(LOG_DEBUG, "signal handler: %s", sys_siglist[sig]));
  longjmp(__signal_jmp[sig], TRUE);
}

void
stimeout(int sec, __sighandler_t hdl, int flags)
{
  ualarm(sec * 1000000, 0);
  ssignal(SIGALRM, hdl, flags);
}

void
svsignal(int sig, struct sigsave *ss)
{
  sigset_t set, old_set;

  sigfillset(&set);
  sigprocmask(SIG_SETMASK, &set, &old_set);
  
  sigaction(sig, NULL, &ss->ss_sa);
  memcpy(&ss->ss_jmp, &__signal_jmp[sig], sizeof(jmp_buf));

  ss->ss_blk = sigismember(&old_set, sig);
  
  sigprocmask(SIG_SETMASK, &old_set, NULL);
  return;
}

void
rssignal(int sig, struct sigsave *ss)
{
  sigset_t set, old_set;

  sigfillset(&set);
  sigprocmask(SIG_SETMASK, &set, &old_set);
  
  memcpy(&__signal_jmp[sig], &ss->ss_jmp, sizeof(jmp_buf));
  sigaction(sig, &ss->ss_sa, NULL);
  
  if(ss->ss_blk)
    sigaddset(&old_set, sig);
  else
    sigdelset(&old_set, sig);

  sigprocmask(SIG_SETMASK, &old_set, NULL);
  return;
}

void
ssignal(int sig, __sighandler_t hdl, int flags)
{
  struct sigaction sigacts;
  sigset_t set;

  sigemptyset(&set);
  sigaddset(&set, sig);
  
  /* Block signal
   */
  sigprocmask(SIG_BLOCK, &set, NULL);

  sigaction(sig, NULL, &sigacts);

  /* Discard pending signal
   */
  if(flags & T_DISCARD)
    {
      sigacts.sa_handler = SIG_IGN;
      sigaction(sig, &sigacts, NULL);
      israised[sig] = FALSE;
    }

  /* Install new handler
   */
  if(hdl != SIG_NULL)
    sigacts.sa_handler = hdl;

  /* Set the flags
   * always reset the flags to prevent surprize
   * currently only SA_RESTART is supported
   */
  if(flags & T_SINTR)
    sigacts.sa_flags = 0;
  else
    sigacts.sa_flags = SA_RESTART;

  sigaction(sig, &sigacts, NULL);

  /* Release blocking
   */
  if(!(flags & T_BLOCK))
    sigprocmask(SIG_UNBLOCK, &set, NULL);
}