summaryrefslogtreecommitdiff
path: root/e2fsprogs/fsck.c
blob: adaf0c538a6c13c3efc7892cc138814b49bf932d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
/* vi: set sw=4 ts=4: */
/*
 * fsck --- A generic, parallelizing front-end for the fsck program.
 * It will automatically try to run fsck programs in parallel if the
 * devices are on separate spindles.  It is based on the same ideas as
 * the generic front end for fsck by David Engel and Fred van Kempen,
 * but it has been completely rewritten from scratch to support
 * parallel execution.
 *
 * Written by Theodore Ts'o, <tytso@mit.edu>
 *
 * Miquel van Smoorenburg (miquels@drinkel.ow.org) 20-Oct-1994:
 *   o Changed -t fstype to behave like with mount when -A (all file
 *     systems) or -M (like mount) is specified.
 *   o fsck looks if it can find the fsck.type program to decide
 *     if it should ignore the fs type. This way more fsck programs
 *     can be added without changing this front-end.
 *   o -R flag skip root file system.
 *
 * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
 *      2001, 2002, 2003, 2004, 2005 by  Theodore Ts'o.
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 */

/* All filesystem specific hooks have been removed.
 * If filesystem cannot be determined, we will execute
 * "fsck.auto". Currently this also happens if you specify
 * UUID=xxx or LABEL=xxx as an object to check.
 * Detection code for that is also probably has to be in fsck.auto.
 *
 * In other words, this is _really_ is just a driver program which
 * spawns actual fsck.something for each filesystem to check.
 * It doesn't guess filesystem types from on-disk format.
 */
//config:config FSCK
//config:	bool "fsck"
//config:	default y
//config:	help
//config:	  fsck is used to check and optionally repair one or more filesystems.
//config:	  In actuality, fsck is simply a front-end for the various file system
//config:	  checkers (fsck.fstype) available under Linux.

//applet:IF_FSCK(APPLET(fsck, BB_DIR_SBIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_FSCK) += fsck.o

//usage:#define fsck_trivial_usage
//usage:       "[-ANPRTV] [-C FD] [-t FSTYPE] [FS_OPTS] [BLOCKDEV]..."
//usage:#define fsck_full_usage "\n\n"
//usage:       "Check and repair filesystems\n"
//usage:     "\n	-A	Walk /etc/fstab and check all filesystems"
//usage:     "\n	-N	Don't execute, just show what would be done"
//usage:     "\n	-P	With -A, check filesystems in parallel"
//usage:     "\n	-R	With -A, skip the root filesystem"
//usage:     "\n	-T	Don't show title on startup"
//usage:     "\n	-V	Verbose"
//usage:     "\n	-C n	Write status information to specified filedescriptor"
//usage:     "\n	-t TYPE	List of filesystem types to check"

#include "libbb.h"

/* "progress indicator" code is somewhat buggy and ext[23] specific.
 * We should be filesystem agnostic. IOW: there should be a well-defined
 * API for fsck.something, NOT ad-hoc hacks in generic fsck. */
#define DO_PROGRESS_INDICATOR 0

/* fsck 1.41.4 (27-Jan-2009) manpage says:
 * 0   - No errors
 * 1   - File system errors corrected
 * 2   - System should be rebooted
 * 4   - File system errors left uncorrected
 * 8   - Operational error
 * 16  - Usage or syntax error
 * 32  - Fsck canceled by user request
 * 128 - Shared library error
 */
#define EXIT_OK          0
#define EXIT_NONDESTRUCT 1
#define EXIT_DESTRUCT    2
#define EXIT_UNCORRECTED 4
#define EXIT_ERROR       8
#define EXIT_USAGE       16
#define FSCK_CANCELED    32     /* Aborted with a signal or ^C */

/*
 * Internal structure for mount table entries.
 */
struct fs_info {
	struct fs_info *next;
	char	*device;
	char	*mountpt;
	char	*type;
	char	*opts;
	int	passno;
	int	flags;
};

#define FLAG_DONE 1
#define FLAG_PROGRESS 2
/*
 * Structure to allow exit codes to be stored
 */
struct fsck_instance {
	struct fsck_instance *next;
	int	pid;
	int	flags;
#if DO_PROGRESS_INDICATOR
	time_t	start_time;
#endif
	char	*prog;
	char	*device;
	char	*base_device; /* /dev/hda for /dev/hdaN etc */
};

static const char ignored_types[] ALIGN1 =
	"ignore\0"
	"iso9660\0"
	"nfs\0"
	"proc\0"
	"sw\0"
	"swap\0"
	"tmpfs\0"
	"devpts\0";

#if 0
static const char really_wanted[] ALIGN1 =
	"minix\0"
	"ext2\0"
	"ext3\0"
	"jfs\0"
	"reiserfs\0"
	"xiafs\0"
	"xfs\0";
#endif

#define BASE_MD "/dev/md"

static char **args;
static int num_args;
static int verbose;

#define FS_TYPE_FLAG_NORMAL 0
#define FS_TYPE_FLAG_OPT    1
#define FS_TYPE_FLAG_NEGOPT 2
static char **fs_type_list;
static uint8_t *fs_type_flag;
static smallint fs_type_negated;

static smallint noexecute;
static smallint serialize;
static smallint skip_root;
/* static smallint like_mount; */
static smallint parallel_root;
static smallint force_all_parallel;

#if DO_PROGRESS_INDICATOR
static smallint progress;
static int progress_fd;
#endif

static int num_running;
static int max_running;
static char *fstype;
static struct fs_info *filesys_info;
static struct fs_info *filesys_last;
static struct fsck_instance *instance_list;

/*
 * Return the "base device" given a particular device; this is used to
 * assure that we only fsck one partition on a particular drive at any
 * one time.  Otherwise, the disk heads will be seeking all over the
 * place.  If the base device cannot be determined, return NULL.
 *
 * The base_device() function returns an allocated string which must
 * be freed.
 */
#if ENABLE_FEATURE_DEVFS
/*
 * Required for the uber-silly devfs /dev/ide/host1/bus2/target3/lun3
 * pathames.
 */
static const char *const devfs_hier[] = {
	"host", "bus", "target", "lun", NULL
};
#endif

static char *base_device(const char *device)
{
	char *str, *cp;
#if ENABLE_FEATURE_DEVFS
	const char *const *hier;
	const char *disk;
	int len;
#endif
	str = xstrdup(device);

	/* Skip over "/dev/"; if it's not present, give up */
	cp = skip_dev_pfx(str);
	if (cp == str)
		goto errout;

	/*
	 * For md devices, we treat them all as if they were all
	 * on one disk, since we don't know how to parallelize them.
	 */
	if (cp[0] == 'm' && cp[1] == 'd') {
		cp[2] = 0;
		return str;
	}

	/* Handle DAC 960 devices */
	if (is_prefixed_with(cp, "rd/")) {
		cp += 3;
		if (cp[0] != 'c' || !isdigit(cp[1])
		 || cp[2] != 'd' || !isdigit(cp[3]))
			goto errout;
		cp[4] = 0;
		return str;
	}

	/* Now let's handle /dev/hd* and /dev/sd* devices.... */
	if ((cp[0] == 'h' || cp[0] == 's') && cp[1] == 'd') {
		cp += 2;
		/* If there's a single number after /dev/hd, skip it */
		if (isdigit(*cp))
			cp++;
		/* What follows must be an alpha char, or give up */
		if (!isalpha(*cp))
			goto errout;
		cp[1] = 0;
		return str;
	}

#if ENABLE_FEATURE_DEVFS
	/* Now let's handle devfs (ugh) names */
	len = 0;
	if (is_prefixed_with(cp, "ide/"))
		len = 4;
	if (is_prefixed_with(cp, "scsi/"))
		len = 5;
	if (len) {
		cp += len;
		/*
		 * Now we proceed down the expected devfs hierarchy.
		 * i.e., .../host1/bus2/target3/lun4/...
		 * If we don't find the expected token, followed by
		 * some number of digits at each level, abort.
		 */
		for (hier = devfs_hier; *hier; hier++) {
			cp = is_prefixed_with(cp, *hier);
			if (!cp)
				goto errout;
			while (*cp != '/' && *cp != '\0') {
				if (!isdigit(*cp))
					goto errout;
				cp++;
			}
//FIXME: what if *cp = '\0' now? cp++ moves past it!!!
			cp++;
		}
		cp[-1] = '\0';
		return str;
	}

	/* Now handle devfs /dev/disc or /dev/disk names */
	disk = NULL;
	if (is_prefixed_with(cp, "discs/"))
		disk = "disc";
	else if (is_prefixed_with(cp, "disks/"))
		disk = "disk";
	if (disk) {
		cp += 6;
		cp = is_prefixed_with(cp, disk);
		if (!cp)
			goto errout;
		while (*cp != '/' && *cp != '\0') {
			if (!isdigit(*cp))
				goto errout;
			cp++;
		}
		*cp = '\0';
		return str;
	}
#endif
 errout:
	free(str);
	return NULL;
}

static void free_instance(struct fsck_instance *p)
{
	free(p->prog);
	free(p->device);
	free(p->base_device);
	free(p);
}

static struct fs_info *create_fs_device(const char *device, const char *mntpnt,
					const char *type, const char *opts,
					int passno)
{
	struct fs_info *fs;

	fs = xzalloc(sizeof(*fs));
	fs->device = xstrdup(device);
	fs->mountpt = xstrdup(mntpnt);
	if (strchr(type, ','))
		type = (char *)"auto";
	fs->type = xstrdup(type);
	fs->opts = xstrdup(opts ? opts : "");
	fs->passno = passno < 0 ? 1 : passno;
	/*fs->flags = 0; */
	/*fs->next = NULL; */

	if (!filesys_info)
		filesys_info = fs;
	else
		filesys_last->next = fs;
	filesys_last = fs;

	return fs;
}

/* Load the filesystem database from /etc/fstab */
static void load_fs_info(const char *filename)
{
	FILE *fstab;
	struct mntent mte;

	fstab = setmntent(filename, "r");
	if (!fstab) {
		bb_perror_msg("can't read '%s'", filename);
		return;
	}

	// Loop through entries
	while (getmntent_r(fstab, &mte, bb_common_bufsiz1, COMMON_BUFSIZE)) {
		//bb_info_msg("CREATE[%s][%s][%s][%s][%d]", mte.mnt_fsname, mte.mnt_dir,
		//	mte.mnt_type, mte.mnt_opts,
		//	mte.mnt_passno);
		create_fs_device(mte.mnt_fsname, mte.mnt_dir,
			mte.mnt_type, mte.mnt_opts,
			mte.mnt_passno);
	}
	endmntent(fstab);
}

/* Lookup filesys in /etc/fstab and return the corresponding entry. */
static struct fs_info *lookup(char *filesys)
{
	struct fs_info *fs;

	for (fs = filesys_info; fs; fs = fs->next) {
		if (strcmp(filesys, fs->device) == 0
		 || (fs->mountpt && strcmp(filesys, fs->mountpt) == 0)
		)
			break;
	}

	return fs;
}

#if DO_PROGRESS_INDICATOR
static int progress_active(void)
{
	struct fsck_instance *inst;

	for (inst = instance_list; inst; inst = inst->next) {
		if (inst->flags & FLAG_DONE)
			continue;
		if (inst->flags & FLAG_PROGRESS)
			return 1;
	}
	return 0;
}
#endif


/*
 * Send a signal to all outstanding fsck child processes
 */
static void kill_all_if_got_signal(void)
{
	static smallint kill_sent;

	struct fsck_instance *inst;

	if (!bb_got_signal || kill_sent)
		return;

	for (inst = instance_list; inst; inst = inst->next) {
		if (inst->flags & FLAG_DONE)
			continue;
		kill(inst->pid, SIGTERM);
	}
	kill_sent = 1;
}

/*
 * Wait for one child process to exit; when it does, unlink it from
 * the list of executing child processes, free, and return its exit status.
 * If there is no exited child, return -1.
 */
static int wait_one(int flags)
{
	int status;
	int sig;
	struct fsck_instance *inst, *prev;
	pid_t pid;

	if (!instance_list)
		return -1;
	/* if (noexecute) { already returned -1; } */

	while (1) {
		pid = waitpid(-1, &status, flags);
		kill_all_if_got_signal();
		if (pid == 0) /* flags == WNOHANG and no children exited */
			return -1;
		if (pid < 0) {
			if (errno == EINTR)
				continue;
			if (errno == ECHILD) { /* paranoia */
				bb_error_msg("wait: no more children");
				return -1;
			}
			bb_perror_msg("wait");
			continue;
		}
		prev = NULL;
		inst = instance_list;
		do {
			if (inst->pid == pid)
				goto child_died;
			prev = inst;
			inst = inst->next;
		} while (inst);
	}
 child_died:

	if (WIFEXITED(status))
		status = WEXITSTATUS(status);
	else if (WIFSIGNALED(status)) {
		sig = WTERMSIG(status);
		status = EXIT_UNCORRECTED;
		if (sig != SIGINT) {
			printf("Warning: %s %s terminated "
				"by signal %d\n",
				inst->prog, inst->device, sig);
			status = EXIT_ERROR;
		}
	} else {
		printf("%s %s: status is %x, should never happen\n",
			inst->prog, inst->device, status);
		status = EXIT_ERROR;
	}

#if DO_PROGRESS_INDICATOR
	if (progress && (inst->flags & FLAG_PROGRESS) && !progress_active()) {
		struct fsck_instance *inst2;
		for (inst2 = instance_list; inst2; inst2 = inst2->next) {
			if (inst2->flags & FLAG_DONE)
				continue;
			if (strcmp(inst2->type, "ext2") != 0
			 && strcmp(inst2->type, "ext3") != 0
			) {
				continue;
			}
			/* ext[23], we will send USR1
			 * (request to start displaying progress bar)
			 *
			 * If we've just started the fsck, wait a tiny
			 * bit before sending the kill, to give it
			 * time to set up the signal handler
			 */
			if (inst2->start_time >= time(NULL) - 1)
				sleep(1);
			kill(inst2->pid, SIGUSR1);
			inst2->flags |= FLAG_PROGRESS;
			break;
		}
	}
#endif

	if (prev)
		prev->next = inst->next;
	else
		instance_list = inst->next;
	if (verbose > 1)
		printf("Finished with %s (exit status %d)\n",
			inst->device, status);
	num_running--;
	free_instance(inst);

	return status;
}

/*
 * Wait until all executing child processes have exited; return the
 * logical OR of all of their exit code values.
 */
#define FLAG_WAIT_ALL           0
#define FLAG_WAIT_ATLEAST_ONE   WNOHANG
static int wait_many(int flags)
{
	int exit_status;
	int global_status = 0;
	int wait_flags = 0;

	while ((exit_status = wait_one(wait_flags)) != -1) {
		global_status |= exit_status;
		wait_flags |= flags;
	}
	return global_status;
}

/*
 * Execute a particular fsck program, and link it into the list of
 * child processes we are waiting for.
 */
static void execute(const char *type, const char *device,
		const char *mntpt /*, int interactive */)
{
	int i;
	struct fsck_instance *inst;
	pid_t pid;

	args[0] = xasprintf("fsck.%s", type);

#if DO_PROGRESS_INDICATOR
	if (progress && !progress_active()) {
		if (strcmp(type, "ext2") == 0
		 || strcmp(type, "ext3") == 0
		) {
			args[XXX] = xasprintf("-C%d", progress_fd); /* 1 */
			inst->flags |= FLAG_PROGRESS;
		}
	}
#endif

	args[num_args - 2] = (char*)device;
	/* args[num_args - 1] = NULL; - already is */

	if (verbose || noexecute) {
		printf("[%s (%d) -- %s]", args[0], num_running,
					mntpt ? mntpt : device);
		for (i = 0; args[i]; i++)
			printf(" %s", args[i]);
		bb_putchar('\n');
	}

	/* Fork and execute the correct program. */
	pid = -1;
	if (!noexecute) {
		pid = spawn(args);
		if (pid < 0)
			bb_simple_perror_msg(args[0]);
	}

#if DO_PROGRESS_INDICATOR
	free(args[XXX]);
#endif

	/* No child, so don't record an instance */
	if (pid <= 0) {
		free(args[0]);
		return;
	}

	inst = xzalloc(sizeof(*inst));
	inst->pid = pid;
	inst->prog = args[0];
	inst->device = xstrdup(device);
	inst->base_device = base_device(device);
#if DO_PROGRESS_INDICATOR
	inst->start_time = time(NULL);
#endif

	/* Add to the list of running fsck's.
	 * (was adding to the end, but adding to the front is simpler...) */
	inst->next = instance_list;
	instance_list = inst;
}

/*
 * Run the fsck program on a particular device
 *
 * If the type is specified using -t, and it isn't prefixed with "no"
 * (as in "noext2") and only one filesystem type is specified, then
 * use that type regardless of what is specified in /etc/fstab.
 *
 * If the type isn't specified by the user, then use either the type
 * specified in /etc/fstab, or "auto".
 */
static void fsck_device(struct fs_info *fs /*, int interactive */)
{
	const char *type;

	if (strcmp(fs->type, "auto") != 0) {
		type = fs->type;
		if (verbose > 2)
			bb_info_msg("using filesystem type '%s' %s",
					type, "from fstab");
	} else if (fstype
	 && (fstype[0] != 'n' || fstype[1] != 'o') /* != "no" */
	 && !is_prefixed_with(fstype, "opts=")
	 && !is_prefixed_with(fstype, "loop")
	 && !strchr(fstype, ',')
	) {
		type = fstype;
		if (verbose > 2)
			bb_info_msg("using filesystem type '%s' %s",
					type, "from -t");
	} else {
		type = "auto";
		if (verbose > 2)
			bb_info_msg("using filesystem type '%s' %s",
					type, "(default)");
	}

	num_running++;
	execute(type, fs->device, fs->mountpt /*, interactive */);
}

/*
 * Returns TRUE if a partition on the same disk is already being
 * checked.
 */
static int device_already_active(char *device)
{
	struct fsck_instance *inst;
	char *base;

	if (force_all_parallel)
		return 0;

#ifdef BASE_MD
	/* Don't check a soft raid disk with any other disk */
	if (instance_list
	 && (is_prefixed_with(instance_list->device, BASE_MD)
	     || is_prefixed_with(device, BASE_MD))
	) {
		return 1;
	}
#endif

	base = base_device(device);
	/*
	 * If we don't know the base device, assume that the device is
	 * already active if there are any fsck instances running.
	 */
	if (!base)
		return (instance_list != NULL);

	for (inst = instance_list; inst; inst = inst->next) {
		if (!inst->base_device || !strcmp(base, inst->base_device)) {
			free(base);
			return 1;
		}
	}

	free(base);
	return 0;
}

/*
 * This function returns true if a particular option appears in a
 * comma-delimited options list
 */
static int opt_in_list(char *opt, char *optlist)
{
	char *s;
	int len;

	if (!optlist)
		return 0;

	len = strlen(opt);
	s = optlist - 1;
	while (1) {
		s = strstr(s + 1, opt);
		if (!s)
			return 0;
		/* neither "opt.." nor "xxx,opt.."? */
		if (s != optlist && s[-1] != ',')
			continue;
		/* neither "..opt" nor "..opt,xxx"? */
		if (s[len] != '\0' && s[len] != ',')
			continue;
		return 1;
	}
}

/* See if the filesystem matches the criteria given by the -t option */
static int fs_match(struct fs_info *fs)
{
	int n, ret, checked_type;
	char *cp;

	if (!fs_type_list)
		return 1;

	ret = 0;
	checked_type = 0;
	n = 0;
	while (1) {
		cp = fs_type_list[n];
		if (!cp)
			break;
		switch (fs_type_flag[n]) {
		case FS_TYPE_FLAG_NORMAL:
			checked_type++;
			if (strcmp(cp, fs->type) == 0)
				ret = 1;
			break;
		case FS_TYPE_FLAG_NEGOPT:
			if (opt_in_list(cp, fs->opts))
				return 0;
			break;
		case FS_TYPE_FLAG_OPT:
			if (!opt_in_list(cp, fs->opts))
				return 0;
			break;
		}
		n++;
	}
	if (checked_type == 0)
		return 1;

	return (fs_type_negated ? !ret : ret);
}

/* Check if we should ignore this filesystem. */
static int ignore(struct fs_info *fs)
{
	/*
	 * If the pass number is 0, ignore it.
	 */
	if (fs->passno == 0)
		return 1;

	/*
	 * If a specific fstype is specified, and it doesn't match,
	 * ignore it.
	 */
	if (!fs_match(fs))
		return 1;

	/* Are we ignoring this type? */
	if (index_in_strings(ignored_types, fs->type) >= 0)
		return 1;

	/* We can and want to check this file system type. */
	return 0;
}

/* Check all file systems, using the /etc/fstab table. */
static int check_all(void)
{
	struct fs_info *fs;
	int status = EXIT_OK;
	smallint not_done_yet;
	smallint pass_done;
	int passno;

	if (verbose)
		puts("Checking all filesystems");

	/*
	 * Do an initial scan over the filesystem; mark filesystems
	 * which should be ignored as done, and resolve any "auto"
	 * filesystem types (done as a side-effect of calling ignore()).
	 */
	for (fs = filesys_info; fs; fs = fs->next)
		if (ignore(fs))
			fs->flags |= FLAG_DONE;

	/*
	 * Find and check the root filesystem.
	 */
	if (!parallel_root) {
		for (fs = filesys_info; fs; fs = fs->next) {
			if (LONE_CHAR(fs->mountpt, '/')) {
				if (!skip_root && !ignore(fs)) {
					fsck_device(fs /*, 1*/);
					status |= wait_many(FLAG_WAIT_ALL);
					if (status > EXIT_NONDESTRUCT)
						return status;
				}
				fs->flags |= FLAG_DONE;
				break;
			}
		}
	}
	/*
	 * This is for the bone-headed user who has root
	 * filesystem listed twice.
	 * "Skip root" will skip _all_ root entries.
	 */
	if (skip_root)
		for (fs = filesys_info; fs; fs = fs->next)
			if (LONE_CHAR(fs->mountpt, '/'))
				fs->flags |= FLAG_DONE;

	not_done_yet = 1;
	passno = 1;
	while (not_done_yet) {
		not_done_yet = 0;
		pass_done = 1;

		for (fs = filesys_info; fs; fs = fs->next) {
			if (bb_got_signal)
				break;
			if (fs->flags & FLAG_DONE)
				continue;
			/*
			 * If the filesystem's pass number is higher
			 * than the current pass number, then we didn't
			 * do it yet.
			 */
			if (fs->passno > passno) {
				not_done_yet = 1;
				continue;
			}
			/*
			 * If a filesystem on a particular device has
			 * already been spawned, then we need to defer
			 * this to another pass.
			 */
			if (device_already_active(fs->device)) {
				pass_done = 0;
				continue;
			}
			/*
			 * Spawn off the fsck process
			 */
			fsck_device(fs /*, serialize*/);
			fs->flags |= FLAG_DONE;

			/*
			 * Only do one filesystem at a time, or if we
			 * have a limit on the number of fsck's extant
			 * at one time, apply that limit.
			 */
			if (serialize
			 || (max_running && (num_running >= max_running))
			) {
				pass_done = 0;
				break;
			}
		}
		if (bb_got_signal)
			break;
		if (verbose > 1)
			printf("--waiting-- (pass %d)\n", passno);
		status |= wait_many(pass_done ? FLAG_WAIT_ALL :
				FLAG_WAIT_ATLEAST_ONE);
		if (pass_done) {
			if (verbose > 1)
				puts("----------------------------------");
			passno++;
		} else
			not_done_yet = 1;
	}
	kill_all_if_got_signal();
	status |= wait_many(FLAG_WAIT_ATLEAST_ONE);
	return status;
}

/*
 * Deal with the fsck -t argument.
 * Huh, for mount "-t novfat,nfs" means "neither vfat nor nfs"!
 * Why here we require "-t novfat,nonfs" ??
 */
static void compile_fs_type(char *fs_type)
{
	char *s;
	int num = 2;
	smallint negate;

	s = fs_type;
	while ((s = strchr(s, ','))) {
		num++;
		s++;
	}

	fs_type_list = xzalloc(num * sizeof(fs_type_list[0]));
	fs_type_flag = xzalloc(num * sizeof(fs_type_flag[0]));
	fs_type_negated = -1; /* not yet known is it negated or not */

	num = 0;
	s = fs_type;
	while (1) {
		char *comma;

		negate = 0;
		if (s[0] == 'n' && s[1] == 'o') { /* "no.." */
			s += 2;
			negate = 1;
		} else if (s[0] == '!') {
			s++;
			negate = 1;
		}

		if (strcmp(s, "loop") == 0)
			/* loop is really short-hand for opts=loop */
			goto loop_special_case;
		if (is_prefixed_with(s, "opts=")) {
			s += 5;
 loop_special_case:
			fs_type_flag[num] = negate ? FS_TYPE_FLAG_NEGOPT : FS_TYPE_FLAG_OPT;
		} else {
			if (fs_type_negated == -1)
				fs_type_negated = negate;
			if (fs_type_negated != negate)
				bb_error_msg_and_die(
"either all or none of the filesystem types passed to -t must be prefixed "
"with 'no' or '!'");
		}
		comma = strchr(s, ',');
		fs_type_list[num++] = comma ? xstrndup(s, comma-s) : xstrdup(s);
		if (!comma)
			break;
		s = comma + 1;
	}
}

static char **new_args(void)
{
	args = xrealloc_vector(args, 2, num_args);
	return &args[num_args++];
}

int fsck_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int fsck_main(int argc UNUSED_PARAM, char **argv)
{
	int i, status;
	/*int interactive;*/
	struct fs_info *fs;
	const char *fstab;
	char *tmp;
	char **devices;
	int num_devices;
	smallint opts_for_fsck;
	smallint doall;
	smallint notitle;

	/* we want wait() to be interruptible */
	signal_no_SA_RESTART_empty_mask(SIGINT, record_signo);
	signal_no_SA_RESTART_empty_mask(SIGTERM, record_signo);

	setbuf(stdout, NULL);

	opts_for_fsck = doall = notitle = 0;
	devices = NULL;
	num_devices = 0;
	new_args(); /* args[0] = NULL, will be replaced by fsck.<type> */
	/* instance_list = NULL; - in bss, so already zeroed */

	while (*++argv) {
		int j;
		int optpos;
		char *options;
		char *arg = *argv;

		/* "/dev/blk" or "/path" or "UUID=xxx" or "LABEL=xxx" */
		if ((arg[0] == '/' && !opts_for_fsck) || strchr(arg, '=')) {
// FIXME: must check that arg is a blkdev, or resolve
// "/path", "UUID=xxx" or "LABEL=xxx" into block device name
// ("UUID=xxx"/"LABEL=xxx" can probably shifted to fsck.auto duties)
			devices = xrealloc_vector(devices, 2, num_devices);
			devices[num_devices++] = arg;
			continue;
		}

		if (arg[0] != '-' || opts_for_fsck) {
			*new_args() = arg;
			continue;
		}

		if (LONE_CHAR(arg + 1, '-')) { /* "--" ? */
			opts_for_fsck = 1;
			continue;
		}

		optpos = 0;
		options = NULL;
		for (j = 1; arg[j]; j++) {
			switch (arg[j]) {
			case 'A':
				doall = 1;
				break;
#if DO_PROGRESS_INDICATOR
			case 'C':
				progress = 1;
				if (arg[++j]) { /* -Cn */
					progress_fd = xatoi_positive(&arg[j]);
					goto next_arg;
				}
				/* -C n */
				if (!*++argv)
					bb_show_usage();
				progress_fd = xatoi_positive(*argv);
				goto next_arg;
#endif
			case 'V':
				verbose++;
				break;
			case 'N':
				noexecute = 1;
				break;
			case 'R':
				skip_root = 1;
				break;
			case 'T':
				notitle = 1;
				break;
/*			case 'M':
				like_mount = 1;
				break; */
			case 'P':
				parallel_root = 1;
				break;
			case 's':
				serialize = 1;
				break;
			case 't':
				if (fstype)
					bb_show_usage();
				if (arg[++j])
					tmp = &arg[j];
				else if (*++argv)
					tmp = *argv;
				else
					bb_show_usage();
				fstype = xstrdup(tmp);
				compile_fs_type(fstype);
				goto next_arg;
			case '?':
				bb_show_usage();
				break;
			default:
				optpos++;
				/* one extra for '\0' */
				options = xrealloc(options, optpos + 2);
				options[optpos] = arg[j];
				break;
			}
		}
 next_arg:
		if (optpos) {
			options[0] = '-';
			options[optpos + 1] = '\0';
			*new_args() = options;
		}
	}
	if (getenv("FSCK_FORCE_ALL_PARALLEL"))
		force_all_parallel = 1;
	tmp = getenv("FSCK_MAX_INST");
	if (tmp)
		max_running = xatoi(tmp);
	new_args(); /* args[num_args - 2] will be replaced by <device> */
	new_args(); /* args[num_args - 1] is the last, NULL element */

	if (!notitle)
		puts("fsck (busybox "BB_VER", "BB_BT")");

	/* Even plain "fsck /dev/hda1" needs fstab to get fs type,
	 * so we are scanning it anyway */
	fstab = getenv("FSTAB_FILE");
	if (!fstab)
		fstab = "/etc/fstab";
	load_fs_info(fstab);

	/*interactive = (num_devices == 1) | serialize;*/

	if (num_devices == 0)
		/*interactive =*/ serialize = doall = 1;
	if (doall)
		return check_all();

	status = 0;
	for (i = 0; i < num_devices; i++) {
		if (bb_got_signal) {
			kill_all_if_got_signal();
			break;
		}

		fs = lookup(devices[i]);
		if (!fs)
			fs = create_fs_device(devices[i], "", "auto", NULL, -1);
		fsck_device(fs /*, interactive */);

		if (serialize
		 || (max_running && (num_running >= max_running))
		) {
			int exit_status = wait_one(0);
			if (exit_status >= 0)
				status |= exit_status;
			if (verbose > 1)
				puts("----------------------------------");
		}
	}
	status |= wait_many(FLAG_WAIT_ALL);
	return status;
}