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#if !defined(lint) && !defined(SABER)
static const char sccsid[] = "@(#)ns_main.c 4.55 (Berkeley) 7/1/91";
static const char rcsid[] = "$Id: ns_signal.c,v 8.13 2000/07/11 07:10:12 vixie Exp $";
#endif /* not lint */
/*
* Copyright (c) 1986, 1989, 1990
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
/*
* Portions Copyright (c) 1993 by Digital Equipment Corporation.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies, and that
* the name of Digital Equipment Corporation not be used in advertising or
* publicity pertaining to distribution of the document or software without
* specific, written prior permission.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
* CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
/*
* Portions Copyright (c) 1996-2000 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
/* Import. */
#include "port_before.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#ifdef SVR4 /* XXX */
# include <sys/sockio.h>
#else
# include <sys/mbuf.h>
#endif
#include <netinet/in.h>
#include <net/route.h>
#include <net/if.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <netdb.h>
#include <pwd.h>
#include <resolv.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
#include <isc/eventlib.h>
#include <isc/logging.h>
#include <isc/memcluster.h>
#include <isc/list.h>
#include "port_after.h"
#include "named.h"
/* Forward. */
static SIG_FN onhup(int);
static SIG_FN onintr(int);
static SIG_FN setdumpflg(int);
static SIG_FN setIncrDbgFlg(int);
static SIG_FN setNoDbgFlg(int);
static SIG_FN setQrylogFlg(int);
static SIG_FN setstatsflg(int);
static SIG_FN discard_pipe(int);
static SIG_FN setreapflg(int);
/* Data. */
static struct {
int sig;
SIG_FN (*hand)(int);
} sighandlers[] = {
#ifdef DEBUG
{ SIGUSR1, setIncrDbgFlg },
{ SIGUSR2, setNoDbgFlg },
#endif
#if defined(SIGWINCH) && defined(QRYLOG)
{ SIGWINCH, setQrylogFlg },
#endif
#if defined(SIGXFSZ)
{ SIGXFSZ, onhup }, /* Wierd DEC Hesiodism, harmless. */
#endif
{ SIGINT, setdumpflg },
{ SIGILL, setstatsflg },
{ SIGHUP, onhup },
{ SIGCHLD, setreapflg },
{ SIGPIPE, discard_pipe },
{ SIGTERM, onintr }
};
static sigset_t mask;
static int blocked = 0;
/* Private. */
static SIG_FN
onhup(int sig) {
ns_need_unsafe(main_need_reload);
}
static SIG_FN
onintr(int sig) {
ns_need_unsafe(main_need_exit);
}
static SIG_FN
setdumpflg(int sig) {
ns_need_unsafe(main_need_dump);
}
#ifdef DEBUG
static SIG_FN
setIncrDbgFlg(int sig) {
desired_debug++;
ns_need_unsafe(main_need_debug);
}
static SIG_FN
setNoDbgFlg(int sig) {
desired_debug = 0;
ns_need_unsafe(main_need_debug);
}
#endif /*DEBUG*/
#if defined(QRYLOG) && defined(SIGWINCH)
static SIG_FN
setQrylogFlg(int sig) {
ns_need_unsafe(main_need_qrylog);
}
#endif /*QRYLOG && SIGWINCH*/
static SIG_FN
setstatsflg(int sig) {
ns_need_unsafe(main_need_statsdump);
}
static SIG_FN
discard_pipe(int sig) {
#ifdef SIGPIPE_ONE_SHOT
int saved_errno = errno;
struct sigaction sa;
memset(&sa, 0, sizeof sa);
sa.sa_mask = mask;
sa.sa_handler = discard_pipe;
if (sigaction(SIGPIPE, &sa, NULL) < 0)
ns_error(ns_log_os, "sigaction failed in discard_pipe: %s",
strerror(errno));
errno = saved_errno;
#endif
}
static SIG_FN
setreapflg(int sig) {
ns_need_unsafe(main_need_reap);
}
/* Public. */
void
init_signals(void) {
int sh;
/* The mask of all our handlers will block all our other handlers. */
(void)sigemptyset(&mask);
for (sh = 0; sh < sizeof sighandlers / sizeof sighandlers[0]; sh++)
sigaddset(&mask, sighandlers[sh].sig);
/* Install our signal handlers with that shared mask. */
for (sh = 0; sh < sizeof sighandlers / sizeof sighandlers[0]; sh++) {
struct sigaction sa;
memset(&sa, 0, sizeof sa);
sa.sa_mask = mask;
sa.sa_handler = sighandlers[sh].hand;
if (sigaction(sighandlers[sh].sig, &sa, NULL) < 0)
ns_error(ns_log_os,
"sigaction failed in set_signal_handler(%d): %s",
sighandlers[sh].sig, strerror(errno));
}
/* Unblock all signals that we expect to handle. */
if (sigprocmask(SIG_UNBLOCK, &mask, NULL) < 0)
ns_panic(ns_log_os, 1, "sigblock failed: %s", strerror(errno));
}
void
block_signals(void) {
INSIST(!blocked);
if (sigprocmask(SIG_BLOCK, &mask, NULL) < 0)
ns_panic(ns_log_os, 1, "sigblock failed: %s", strerror(errno));
blocked = 1;
}
void
unblock_signals(void) {
INSIST(blocked);
if (sigprocmask(SIG_UNBLOCK, &mask, NULL) < 0)
ns_panic(ns_log_os, 1, "sigblock failed: %s", strerror(errno));
blocked = 0;
}
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