freebsd-skq/sbin/fsck_ffs/main.c
Kirk McKusick f190f9193b Fix fsck_ufs segfaults with gjournal (SU+J)
The segfault was being hit in ckfini() (sbin/fsck_ffs/fsutil.c)
while attempting to traverse the buffer cache to flush dirty buffers.
The tail queue used for the buffer cache was not initialized before
dropping into gjournal_check(). Move the buffer initialization earlier
so that it has been done before calling gjournal_check().

Reported by:  crypt47, nvass
Fix by:       Robert Wing
Tested by:    Robert Wing
PR:           255030
PR:           255979
MFC after:    3 days
Sponsored by: Netflix
2021-05-21 13:42:37 -07:00

755 lines
19 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1980, 1986, 1993
* 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. 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.
*/
#if 0
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1980, 1986, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)main.c 8.6 (Berkeley) 5/14/95";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#define IN_RTLD /* So we pickup the P_OSREL defines */
#include <sys/param.h>
#include <sys/file.h>
#include <sys/mount.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/disklabel.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <err.h>
#include <errno.h>
#include <fstab.h>
#include <grp.h>
#include <inttypes.h>
#include <libufs.h>
#include <mntopts.h>
#include <paths.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include "fsck.h"
static int restarts;
static void usage(void) __dead2;
static intmax_t argtoimax(int flag, const char *req, const char *str, int base);
static int checkfilesys(char *filesys);
static int chkdoreload(struct statfs *mntp);
static struct statfs *getmntpt(const char *);
int
main(int argc, char *argv[])
{
int ch;
struct rlimit rlimit;
struct itimerval itimerval;
int fsret;
int ret = 0;
sync();
skipclean = 1;
inoopt = 0;
while ((ch = getopt(argc, argv, "b:Bc:CdEfFm:npRrSyZz")) != -1) {
switch (ch) {
case 'b':
skipclean = 0;
bflag = argtoimax('b', "number", optarg, 10);
printf("Alternate super block location: %jd\n", bflag);
break;
case 'B':
bkgrdflag = 1;
break;
case 'c':
skipclean = 0;
cvtlevel = argtoimax('c', "conversion level", optarg,
10);
if (cvtlevel < 3)
errx(EEXIT, "cannot do level %d conversion",
cvtlevel);
break;
case 'd':
debug++;
break;
case 'E':
Eflag++;
break;
case 'f':
skipclean = 0;
break;
case 'F':
bkgrdcheck = 1;
break;
case 'm':
lfmode = argtoimax('m', "mode", optarg, 8);
if (lfmode &~ 07777)
errx(EEXIT, "bad mode to -m: %o", lfmode);
printf("** lost+found creation mode %o\n", lfmode);
break;
case 'n':
nflag++;
yflag = 0;
break;
case 'p':
preen++;
/*FALLTHROUGH*/
case 'C':
ckclean++;
break;
case 'R':
wantrestart = 1;
break;
case 'r':
inoopt++;
break;
case 'S':
surrender = 1;
break;
case 'y':
yflag++;
nflag = 0;
break;
case 'Z':
Zflag++;
break;
case 'z':
zflag++;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (!argc)
usage();
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
(void)signal(SIGINT, catch);
if (ckclean)
(void)signal(SIGQUIT, catchquit);
signal(SIGINFO, infohandler);
if (bkgrdflag) {
signal(SIGALRM, alarmhandler);
itimerval.it_interval.tv_sec = 5;
itimerval.it_interval.tv_usec = 0;
itimerval.it_value.tv_sec = 5;
itimerval.it_value.tv_usec = 0;
setitimer(ITIMER_REAL, &itimerval, NULL);
}
/*
* Push up our allowed memory limit so we can cope
* with huge file systems.
*/
if (getrlimit(RLIMIT_DATA, &rlimit) == 0) {
rlimit.rlim_cur = rlimit.rlim_max;
(void)setrlimit(RLIMIT_DATA, &rlimit);
}
while (argc > 0) {
if ((fsret = checkfilesys(*argv)) == ERESTART)
continue;
ret |= fsret;
argc--;
argv++;
}
if (returntosingle)
ret = 2;
exit(ret);
}
static intmax_t
argtoimax(int flag, const char *req, const char *str, int base)
{
char *cp;
intmax_t ret;
ret = strtoimax(str, &cp, base);
if (cp == str || *cp)
errx(EEXIT, "-%c flag requires a %s", flag, req);
return (ret);
}
/*
* Check the specified file system.
*/
/* ARGSUSED */
static int
checkfilesys(char *filesys)
{
ufs2_daddr_t n_ffree, n_bfree;
struct dups *dp;
struct statfs *mntp;
struct stat snapdir;
struct group *grp;
struct iovec *iov;
char errmsg[255];
int ofsmodified;
int iovlen;
intmax_t blks, files;
size_t size;
iov = NULL;
iovlen = 0;
errmsg[0] = '\0';
fsutilinit();
fsckinit();
cdevname = filesys;
if (debug && ckclean)
pwarn("starting\n");
/*
* Make best effort to get the disk name. Check first to see
* if it is listed among the mounted file systems. Failing that
* check to see if it is listed in /etc/fstab.
*/
mntp = getmntpt(filesys);
if (mntp != NULL)
filesys = mntp->f_mntfromname;
else
filesys = blockcheck(filesys);
/*
* If -F flag specified, check to see whether a background check
* is possible and needed. If possible and needed, exit with
* status zero. Otherwise exit with status non-zero. A non-zero
* exit status will cause a foreground check to be run.
*/
sblock_init();
bufinit();
if (bkgrdcheck) {
if ((fsreadfd = open(filesys, O_RDONLY)) < 0 || readsb(0) == 0)
exit(3); /* Cannot read superblock */
close(fsreadfd);
/* Earlier background failed or journaled */
if (sblock.fs_flags & (FS_NEEDSFSCK | FS_SUJ))
exit(4);
if ((sblock.fs_flags & FS_DOSOFTDEP) == 0)
exit(5); /* Not running soft updates */
size = MIBSIZE;
if (sysctlnametomib("vfs.ffs.adjrefcnt", adjrefcnt, &size) < 0)
exit(6); /* Lacks kernel support */
if ((mntp == NULL && sblock.fs_clean == 1) ||
(mntp != NULL && (sblock.fs_flags & FS_UNCLEAN) == 0))
exit(7); /* Filesystem clean, report it now */
exit(0);
}
if (ckclean && skipclean) {
/*
* If file system is gjournaled, check it here.
*/
if ((fsreadfd = open(filesys, O_RDONLY)) < 0 || readsb(0) == 0)
exit(3); /* Cannot read superblock */
if (nflag || (fswritefd = open(filesys, O_WRONLY)) < 0) {
fswritefd = -1;
if (preen)
pfatal("NO WRITE ACCESS");
printf(" (NO WRITE)");
}
if ((sblock.fs_flags & FS_GJOURNAL) != 0) {
//printf("GJournaled file system detected on %s.\n",
// filesys);
if (sblock.fs_clean == 1) {
pwarn("FILE SYSTEM CLEAN; SKIPPING CHECKS\n");
exit(0);
}
if ((sblock.fs_flags & (FS_UNCLEAN | FS_NEEDSFSCK)) == 0) {
gjournal_check(filesys);
if (chkdoreload(mntp) == 0)
exit(0);
exit(4);
} else {
pfatal(
"UNEXPECTED INCONSISTENCY, CANNOT RUN FAST FSCK\n");
close(fsreadfd);
close(fswritefd);
}
}
}
/*
* If we are to do a background check:
* Get the mount point information of the file system
* create snapshot file
* return created snapshot file
* if not found, clear bkgrdflag and proceed with normal fsck
*/
if (bkgrdflag) {
if (mntp == NULL) {
bkgrdflag = 0;
pfatal("NOT MOUNTED, CANNOT RUN IN BACKGROUND\n");
} else if ((mntp->f_flags & MNT_SOFTDEP) == 0) {
bkgrdflag = 0;
pfatal(
"NOT USING SOFT UPDATES, CANNOT RUN IN BACKGROUND\n");
} else if ((mntp->f_flags & MNT_RDONLY) != 0) {
bkgrdflag = 0;
pfatal("MOUNTED READ-ONLY, CANNOT RUN IN BACKGROUND\n");
} else if ((fsreadfd = open(filesys, O_RDONLY)) >= 0) {
if (readsb(0) != 0) {
if (sblock.fs_flags & (FS_NEEDSFSCK | FS_SUJ)) {
bkgrdflag = 0;
pfatal(
"UNEXPECTED INCONSISTENCY, CANNOT RUN IN BACKGROUND\n");
}
if ((sblock.fs_flags & FS_UNCLEAN) == 0 &&
skipclean && ckclean) {
/*
* file system is clean;
* skip snapshot and report it clean
*/
pwarn(
"FILE SYSTEM CLEAN; SKIPPING CHECKS\n");
goto clean;
}
}
close(fsreadfd);
}
if (bkgrdflag) {
snprintf(snapname, sizeof snapname, "%s/.snap",
mntp->f_mntonname);
if (stat(snapname, &snapdir) < 0) {
if (errno != ENOENT) {
bkgrdflag = 0;
pfatal(
"CANNOT FIND SNAPSHOT DIRECTORY %s: %s, CANNOT RUN IN BACKGROUND\n",
snapname, strerror(errno));
} else if ((grp = getgrnam("operator")) == NULL ||
mkdir(snapname, 0770) < 0 ||
chown(snapname, -1, grp->gr_gid) < 0 ||
chmod(snapname, 0770) < 0) {
bkgrdflag = 0;
pfatal(
"CANNOT CREATE SNAPSHOT DIRECTORY %s: %s, CANNOT RUN IN BACKGROUND\n",
snapname, strerror(errno));
}
} else if (!S_ISDIR(snapdir.st_mode)) {
bkgrdflag = 0;
pfatal(
"%s IS NOT A DIRECTORY, CANNOT RUN IN BACKGROUND\n",
snapname);
}
}
if (bkgrdflag) {
snprintf(snapname, sizeof snapname,
"%s/.snap/fsck_snapshot", mntp->f_mntonname);
build_iovec(&iov, &iovlen, "fstype", "ffs", 4);
build_iovec(&iov, &iovlen, "from", snapname,
(size_t)-1);
build_iovec(&iov, &iovlen, "fspath", mntp->f_mntonname,
(size_t)-1);
build_iovec(&iov, &iovlen, "errmsg", errmsg,
sizeof(errmsg));
build_iovec(&iov, &iovlen, "update", NULL, 0);
build_iovec(&iov, &iovlen, "snapshot", NULL, 0);
while (nmount(iov, iovlen, mntp->f_flags) < 0) {
if (errno == EEXIST && unlink(snapname) == 0)
continue;
bkgrdflag = 0;
pfatal("CANNOT CREATE SNAPSHOT %s: %s %s\n",
snapname, strerror(errno), errmsg);
break;
}
if (bkgrdflag != 0)
filesys = snapname;
}
}
switch (setup(filesys)) {
case 0:
if (preen)
pfatal("CAN'T CHECK FILE SYSTEM.");
return (EEXIT);
case -1:
clean:
pwarn("clean, %ld free ", (long)(sblock.fs_cstotal.cs_nffree +
sblock.fs_frag * sblock.fs_cstotal.cs_nbfree));
printf("(%jd frags, %jd blocks, %.1f%% fragmentation)\n",
(intmax_t)sblock.fs_cstotal.cs_nffree,
(intmax_t)sblock.fs_cstotal.cs_nbfree,
sblock.fs_cstotal.cs_nffree * 100.0 / sblock.fs_dsize);
return (0);
}
/*
* Determine if we can and should do journal recovery.
*/
if ((sblock.fs_flags & FS_SUJ) == FS_SUJ) {
if ((sblock.fs_flags & FS_NEEDSFSCK) != FS_NEEDSFSCK && skipclean) {
sujrecovery = 1;
if (suj_check(filesys) == 0) {
printf("\n***** FILE SYSTEM MARKED CLEAN *****\n");
if (chkdoreload(mntp) == 0)
exit(0);
exit(4);
}
sujrecovery = 0;
printf("** Skipping journal, falling through to full fsck\n\n");
}
/*
* Write the superblock so we don't try to recover the
* journal on another pass. If this is the only change
* to the filesystem, we do not want it to be called
* out as modified.
*/
sblock.fs_mtime = time(NULL);
sbdirty();
ofsmodified = fsmodified;
flush(fswritefd, &sblk);
fsmodified = ofsmodified;
}
/*
* If the filesystem was run on an old kernel that did not
* support check hashes, clear the check-hash flags so that
* we do not try to verify them.
*/
if ((sblock.fs_flags & FS_METACKHASH) == 0)
sblock.fs_metackhash = 0;
/*
* If we are running on a kernel that can provide check hashes
* that are not yet enabled for the filesystem and we are
* running manually without the -y flag, offer to add any
* supported check hashes that are not already enabled.
*/
ckhashadd = 0;
if (preen == 0 && yflag == 0 && sblock.fs_magic != FS_UFS1_MAGIC &&
fswritefd != -1 && getosreldate() >= P_OSREL_CK_CYLGRP) {
if ((sblock.fs_metackhash & CK_CYLGRP) == 0 &&
reply("ADD CYLINDER GROUP CHECK-HASH PROTECTION") != 0) {
ckhashadd |= CK_CYLGRP;
sblock.fs_metackhash |= CK_CYLGRP;
}
if ((sblock.fs_metackhash & CK_SUPERBLOCK) == 0 &&
getosreldate() >= P_OSREL_CK_SUPERBLOCK &&
reply("ADD SUPERBLOCK CHECK-HASH PROTECTION") != 0) {
ckhashadd |= CK_SUPERBLOCK;
sblock.fs_metackhash |= CK_SUPERBLOCK;
}
if ((sblock.fs_metackhash & CK_INODE) == 0 &&
getosreldate() >= P_OSREL_CK_INODE &&
reply("ADD INODE CHECK-HASH PROTECTION") != 0) {
ckhashadd |= CK_INODE;
sblock.fs_metackhash |= CK_INODE;
}
#ifdef notyet
if ((sblock.fs_metackhash & CK_INDIR) == 0 &&
getosreldate() >= P_OSREL_CK_INDIR &&
reply("ADD INDIRECT BLOCK CHECK-HASH PROTECTION") != 0) {
ckhashadd |= CK_INDIR;
sblock.fs_metackhash |= CK_INDIR;
}
if ((sblock.fs_metackhash & CK_DIR) == 0 &&
getosreldate() >= P_OSREL_CK_DIR &&
reply("ADD DIRECTORY CHECK-HASH PROTECTION") != 0) {
ckhashadd |= CK_DIR;
sblock.fs_metackhash |= CK_DIR;
}
#endif /* notyet */
if (ckhashadd != 0) {
sblock.fs_flags |= FS_METACKHASH;
sbdirty();
}
}
/*
* Cleared if any questions answered no. Used to decide if
* the superblock should be marked clean.
*/
resolved = 1;
/*
* 1: scan inodes tallying blocks used
*/
if (preen == 0) {
printf("** Last Mounted on %s\n", sblock.fs_fsmnt);
if (mntp != NULL && mntp->f_flags & MNT_ROOTFS)
printf("** Root file system\n");
printf("** Phase 1 - Check Blocks and Sizes\n");
}
clock_gettime(CLOCK_REALTIME_PRECISE, &startprog);
pass1();
IOstats("Pass1");
/*
* 1b: locate first references to duplicates, if any
*/
if (duplist) {
if (preen || usedsoftdep)
pfatal("INTERNAL ERROR: dups with %s%s%s",
preen ? "-p" : "",
(preen && usedsoftdep) ? " and " : "",
usedsoftdep ? "softupdates" : "");
printf("** Phase 1b - Rescan For More DUPS\n");
pass1b();
IOstats("Pass1b");
}
/*
* 2: traverse directories from root to mark all connected directories
*/
if (preen == 0)
printf("** Phase 2 - Check Pathnames\n");
pass2();
IOstats("Pass2");
/*
* 3: scan inodes looking for disconnected directories
*/
if (preen == 0)
printf("** Phase 3 - Check Connectivity\n");
pass3();
IOstats("Pass3");
/*
* 4: scan inodes looking for disconnected files; check reference counts
*/
if (preen == 0)
printf("** Phase 4 - Check Reference Counts\n");
pass4();
IOstats("Pass4");
/*
* 5: check and repair resource counts in cylinder groups
*/
if (preen == 0)
printf("** Phase 5 - Check Cyl groups\n");
pass5();
IOstats("Pass5");
/*
* print out summary statistics
*/
n_ffree = sblock.fs_cstotal.cs_nffree;
n_bfree = sblock.fs_cstotal.cs_nbfree;
files = maxino - UFS_ROOTINO - sblock.fs_cstotal.cs_nifree - n_files;
blks = n_blks +
sblock.fs_ncg * (cgdmin(&sblock, 0) - cgsblock(&sblock, 0));
blks += cgsblock(&sblock, 0) - cgbase(&sblock, 0);
blks += howmany(sblock.fs_cssize, sblock.fs_fsize);
blks = maxfsblock - (n_ffree + sblock.fs_frag * n_bfree) - blks;
if (bkgrdflag && (files > 0 || blks > 0)) {
countdirs = sblock.fs_cstotal.cs_ndir - countdirs;
pwarn("Reclaimed: %ld directories, %jd files, %jd fragments\n",
countdirs, files - countdirs, blks);
}
pwarn("%ld files, %jd used, %ju free ",
(long)n_files, (intmax_t)n_blks,
(uintmax_t)n_ffree + sblock.fs_frag * n_bfree);
printf("(%ju frags, %ju blocks, %.1f%% fragmentation)\n",
(uintmax_t)n_ffree, (uintmax_t)n_bfree,
n_ffree * 100.0 / sblock.fs_dsize);
if (debug) {
if (files < 0)
printf("%jd inodes missing\n", -files);
if (blks < 0)
printf("%jd blocks missing\n", -blks);
if (duplist != NULL) {
printf("The following duplicate blocks remain:");
for (dp = duplist; dp; dp = dp->next)
printf(" %jd,", (intmax_t)dp->dup);
printf("\n");
}
}
duplist = (struct dups *)0;
muldup = (struct dups *)0;
inocleanup();
if (fsmodified) {
sblock.fs_time = time(NULL);
sbdirty();
}
if (cvtlevel && (sblk.b_flags & B_DIRTY) != 0) {
/*
* Write out the duplicate super blocks
*/
if (sbput(fswritefd, &sblock, sblock.fs_ncg) == 0)
fsmodified = 1;
}
if (rerun)
resolved = 0;
/*
* Check to see if the file system is mounted read-write.
*/
if (bkgrdflag == 0 && mntp != NULL && (mntp->f_flags & MNT_RDONLY) == 0)
resolved = 0;
ckfini(resolved);
if (fsmodified && !preen)
printf("\n***** FILE SYSTEM WAS MODIFIED *****\n");
if (rerun) {
if (wantrestart && (restarts++ < 10) &&
(preen || reply("RESTART")))
return (ERESTART);
printf("\n***** PLEASE RERUN FSCK *****\n");
}
if (chkdoreload(mntp) != 0) {
if (!fsmodified)
return (0);
if (!preen)
printf("\n***** REBOOT NOW *****\n");
sync();
return (4);
}
return (rerun ? ERERUN : 0);
}
static int
chkdoreload(struct statfs *mntp)
{
struct iovec *iov;
int iovlen;
char errmsg[255];
if (mntp == NULL)
return (0);
iov = NULL;
iovlen = 0;
errmsg[0] = '\0';
/*
* We modified a mounted file system. Do a mount update on
* it unless it is read-write, so we can continue using it
* as safely as possible.
*/
if (mntp->f_flags & MNT_RDONLY) {
build_iovec(&iov, &iovlen, "fstype", "ffs", 4);
build_iovec(&iov, &iovlen, "from", mntp->f_mntfromname,
(size_t)-1);
build_iovec(&iov, &iovlen, "fspath", mntp->f_mntonname,
(size_t)-1);
build_iovec(&iov, &iovlen, "errmsg", errmsg,
sizeof(errmsg));
build_iovec(&iov, &iovlen, "update", NULL, 0);
build_iovec(&iov, &iovlen, "reload", NULL, 0);
/*
* XX: We need the following line until we clean up
* nmount parsing of root mounts and NFS root mounts.
*/
build_iovec(&iov, &iovlen, "ro", NULL, 0);
if (nmount(iov, iovlen, mntp->f_flags) == 0) {
return (0);
}
pwarn("mount reload of '%s' failed: %s %s\n\n",
mntp->f_mntonname, strerror(errno), errmsg);
return (1);
}
return (0);
}
/*
* Get the mount point information for name.
*/
static struct statfs *
getmntpt(const char *name)
{
struct stat devstat, mntdevstat;
char device[sizeof(_PATH_DEV) - 1 + MNAMELEN];
char *ddevname;
struct statfs *mntbuf, *statfsp;
int i, mntsize, isdev;
if (stat(name, &devstat) != 0)
return (NULL);
if (S_ISCHR(devstat.st_mode) || S_ISBLK(devstat.st_mode))
isdev = 1;
else
isdev = 0;
mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
for (i = 0; i < mntsize; i++) {
statfsp = &mntbuf[i];
ddevname = statfsp->f_mntfromname;
if (*ddevname != '/') {
if (strlen(_PATH_DEV) + strlen(ddevname) + 1 >
sizeof(statfsp->f_mntfromname))
continue;
strcpy(device, _PATH_DEV);
strcat(device, ddevname);
strcpy(statfsp->f_mntfromname, device);
}
if (isdev == 0) {
if (strcmp(name, statfsp->f_mntonname))
continue;
return (statfsp);
}
if (stat(ddevname, &mntdevstat) == 0 &&
mntdevstat.st_rdev == devstat.st_rdev)
return (statfsp);
}
statfsp = NULL;
return (statfsp);
}
static void
usage(void)
{
(void) fprintf(stderr,
"usage: %s [-BCdEFfnpRrSyZ] [-b block] [-c level] [-m mode] filesystem ...\n",
getprogname());
exit(1);
}
void
infohandler(int sig __unused)
{
got_siginfo = 1;
}
void
alarmhandler(int sig __unused)
{
got_sigalarm = 1;
}