Files
cdesktop/cde/lib/tt/mini_isam/issignals.c
2012-03-10 18:58:32 +00:00

99 lines
2.9 KiB
C

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these librararies and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/*%% (c) Copyright 1993, 1994 Hewlett-Packard Company */
/*%% (c) Copyright 1993, 1994 International Business Machines Corp. */
/*%% (c) Copyright 1993, 1994 Sun Microsystems, Inc. */
/*%% (c) Copyright 1993, 1994 Novell, Inc. */
/*%% $XConsortium: issignals.c /main/3 1995/10/23 11:44:41 rswiston $ */
#ifndef lint
static char sccsid[] = "@(#)issignals.c 1.7 89/08/30 Copyr 1988 Sun Micro";
#endif
/*
* Copyright (c) 1988 by Sun Microsystems, Inc.
*/
/*
* issignals.c
*
* Description:
* Signal masking functions
*/
#include "isam_impl.h"
#include <signal.h>
/*
* _issignal_mask() is called at the beginning of each ISAM update operation
* to mask signals for the duration of the operation. _issignals_unmask()
* is called at the end of the operation to restore the original signal
* mask.
*
* _issignals_cntl() enables/disables this signal masking facility.
* (the default is "mask the signals").
*
* The variable already_masked is used to provide more robustness: it
* will prevent permanent signal masking due to bugs in the ISAM package.
* The permanent masking of signals would happen if _issignals_mask()
* were called twice in a row.
*/
static int do_mask = 1; /* default value */
static int already_masked;
static sigset_t oldmask;
static sigset_t allsignals;
_issignals_cntl(opt)
int opt; /* 1 will enable masking */
/* 0 will disable masking */
{
int oldmask = do_mask;
do_mask = opt ? 1 : 0;
return (oldmask);
}
_issignals_mask()
{
if (do_mask && !already_masked) {
(void) sigfillset(&allsignals);
(void) sigdelset(&allsignals, SIGTRAP);
(void) sigdelset(&allsignals, SIGSEGV);
(void) sigdelset(&allsignals, SIGILL);
(void) sigdelset(&allsignals, SIGBUS);
(void) sigprocmask(SIG_SETMASK, &allsignals, &oldmask);
already_masked = 1;
}
}
_issignals_unmask()
{
if (do_mask) {
(void)sigprocmask(SIG_SETMASK, &oldmask, NULL);
already_masked = 0;
}
}