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static char rcsid[]="$Id$";
/*
* Copyright (C) 1996-8 Michael R. Elkins <me@cs.hmc.edu>
*
* 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 "mutt.h"
#include "mutt_curses.h"
#include <signal.h>
#include <string.h>
#include <sys/wait.h>
static sigset_t Sigset;
static int IsEndwin = 0;
static pid_t *PidList = NULL;
static int PidListLen = 0;
/* Attempt to catch "ordinary" signals and shut down gracefully. */
RETSIGTYPE mutt_exit_handler (int sig)
{
curs_set (1);
endwin (); /* just to be safe */
#if SYS_SIGLIST_DECLARED
printf(_("Caught %s... Exiting.\n"), sys_siglist[sig]);
#else
#if (__sun__ && __svr4__)
printf(_("Caught %s... Exiting.\n"), _sys_siglist[sig]);
#else
printf(_("Caught signal %d... Exiting.\n"), sig);
#endif
#endif
exit (0);
}
static void reap_children (void)
{
int i, flag;
/* at this point we don't know which child died */
for (i = 0; i < PidListLen; i++)
{
if (PidList[i])
{
/* try to reap child "i" */
flag = 0;
while (waitpid (PidList[i], NULL, WNOHANG) > 0)
flag = 1;
/* remove child from list if reaped */
if (flag)
PidList[i] = 0;
/* don't break here */
}
}
}
void mutt_add_child_pid (pid_t pid)
{
int i;
for (i = 0; i < PidListLen; i++)
{
if (PidList[i] == 0)
{
PidList[i] = pid;
break;
}
}
if (i >= PidListLen)
{
/* quite a few children around... */
safe_realloc ((void **) &PidList, (PidListLen += 2) * sizeof (pid_t));
PidList[i++] = pid;
for (; i < PidListLen; i++)
PidList[i] = 0;
}
}
RETSIGTYPE sighandler (int sig)
{
switch (sig)
{
case SIGTSTP: /* user requested a suspend */
if(!option(OPTSUSPEND))
break;
IsEndwin = isendwin ();
curs_set (1);
if (!IsEndwin)
endwin ();
kill (0, SIGSTOP);
case SIGCONT:
if (!IsEndwin)
refresh ();
mutt_curs_set (-1);
break;
#if defined (USE_SLANG_CURSES) || defined (HAVE_RESIZETERM)
case SIGWINCH:
Signals |= S_SIGWINCH;
break;
#endif
case SIGINT:
Signals |= S_INTERRUPT;
break;
case SIGCHLD:
reap_children ();
break;
}
}
#ifdef USE_SLANG_CURSES
int mutt_intr_hook (void)
{
return (-1);
}
#endif /* USE_SLANG_CURSES */
void mutt_signal_init (void)
{
struct sigaction act;
memset (&act, 0, sizeof (struct sigaction));
act.sa_handler = SIG_IGN;
sigaction (SIGPIPE, &act, NULL);
act.sa_handler = mutt_exit_handler;
sigaction (SIGTERM, &act, NULL);
sigaction (SIGHUP, &act, NULL);
act.sa_handler = sighandler;
#ifdef SA_INTERRUPT
/* POSIX.1 uses SA_RESTART, but SunOS 4.x uses this instead */
act.sa_flags = SA_INTERRUPT;
#endif
sigaction (SIGCONT, &act, NULL);
sigaction (SIGINT, &act, NULL);
/* SIGTSTP is the one signal in which we want to restart a system call if it
* was interrupted in progress. This is especially important if we are in
* the middle of a system() call, like if the user is editing a message.
* Otherwise, the system() will exit when SIGCONT is received and Mutt will
* resume even though the subprocess may not be finished.
*/
#ifdef SA_RESTART
act.sa_flags = SA_RESTART;
#else
act.sa_flags = 0;
#endif
sigaction (SIGTSTP, &act, NULL);
#if defined (USE_SLANG_CURSES) || defined (HAVE_RESIZETERM)
sigaction (SIGWINCH, &act, NULL);
#endif
/* we don't want to mess with stopped children */
act.sa_flags |= SA_NOCLDSTOP;
sigaction (SIGCHLD, &act, NULL);
#ifdef USE_SLANG_CURSES
/* This bit of code is required because of the implementation of
* SLcurses_wgetch(). If a signal is received (like SIGWINCH) when we
* are in blocking mode, SLsys_getkey() will not return an error unless
* a handler function is defined and it returns -1. This is needed so
* that if the user resizes the screen while at a prompt, it will just
* abort and go back to the main-menu.
*/
SLang_getkey_intr_hook = mutt_intr_hook;
#endif
}
/* signals which are important to block while doing critical ops */
void mutt_block_signals (void)
{
if (!option (OPTSIGNALSBLOCKED))
{
sigemptyset (&Sigset);
sigaddset (&Sigset, SIGINT);
sigaddset (&Sigset, SIGWINCH);
sigaddset (&Sigset, SIGHUP);
sigaddset (&Sigset, SIGTERM);
sigaddset (&Sigset, SIGTSTP);
sigprocmask (SIG_BLOCK, &Sigset, 0);
set_option (OPTSIGNALSBLOCKED);
}
}
/* restore the previous signal mask */
void mutt_unblock_signals (void)
{
if (option (OPTSIGNALSBLOCKED))
{
sigprocmask (SIG_UNBLOCK, &Sigset, 0);
unset_option (OPTSIGNALSBLOCKED);
}
}
void mutt_block_signals_system (void)
{
struct sigaction sa;
if (! option (OPTSIGNALSBLOCKED))
{
sa.sa_handler = SIG_IGN;
sa.sa_flags = 0;
sigaction (SIGINT, &sa, NULL);
sigaction (SIGQUIT, &sa, NULL);
sigemptyset (&Sigset);
sigaddset (&Sigset, SIGCHLD);
sigprocmask (SIG_BLOCK, &Sigset, 0);
set_option (OPTSIGNALSBLOCKED);
}
}
void mutt_unblock_signals_system (int catch)
{
struct sigaction sa;
if (option (OPTSIGNALSBLOCKED))
{
sa.sa_flags = 0;
sa.sa_handler = mutt_exit_handler;
sigaction (SIGQUIT, &sa, NULL);
if (catch)
sa.sa_handler = sighandler;
sigaction (SIGINT, &sa, NULL);
sigprocmask (SIG_UNBLOCK, &Sigset, NULL);
unset_option (OPTSIGNALSBLOCKED);
}
}
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