aboutsummaryrefslogtreecommitdiff
path: root/coreutils/ls.c
blob: 72f58c253a59ce3060086a56e6d9aece06b5f3d0 (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
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
/* vi: set sw=4 ts=4: */
/*
 * tiny-ls.c version 0.1.0: A minimalist 'ls'
 * Copyright (C) 1996 Brian Candler <B.Candler@pobox.com>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

/* [date unknown. Perhaps before year 2000]
 * To achieve a small memory footprint, this version of 'ls' doesn't do any
 * file sorting, and only has the most essential command line switches
 * (i.e., the ones I couldn't live without :-) All features which involve
 * linking in substantial chunks of libc can be disabled.
 *
 * Although I don't really want to add new features to this program to
 * keep it small, I *am* interested to receive bug fixes and ways to make
 * it more portable.
 *
 * KNOWN BUGS:
 * 1. hidden files can make column width too large
 *
 * NON-OPTIMAL BEHAVIOUR:
 * 1. autowidth reads directories twice
 * 2. if you do a short directory listing without filetype characters
 *    appended, there's no need to stat each one
 * PORTABILITY:
 * 1. requires lstat (BSD) - how do you do it without?
 *
 * [2009-03]
 * ls sorts listing now, and supports almost all options.
 */
#include "libbb.h"
#include "unicode.h"


/* This is a NOEXEC applet. Be very careful! */


#if ENABLE_FTPD
/* ftpd uses ls, and without timestamps Mozilla won't understand
 * ftpd's LIST output.
 */
# undef CONFIG_FEATURE_LS_TIMESTAMPS
# undef ENABLE_FEATURE_LS_TIMESTAMPS
# undef IF_FEATURE_LS_TIMESTAMPS
# undef IF_NOT_FEATURE_LS_TIMESTAMPS
# define CONFIG_FEATURE_LS_TIMESTAMPS 1
# define ENABLE_FEATURE_LS_TIMESTAMPS 1
# define IF_FEATURE_LS_TIMESTAMPS(...) __VA_ARGS__
# define IF_NOT_FEATURE_LS_TIMESTAMPS(...)
#endif


enum {
TERMINAL_WIDTH  = 80,           /* use 79 if terminal has linefold bug */
COLUMN_GAP      = 2,            /* includes the file type char */

/* what is the overall style of the listing */
STYLE_COLUMNS   = 1 << 21,      /* fill columns */
STYLE_LONG      = 2 << 21,      /* one record per line, extended info */
STYLE_SINGLE    = 3 << 21,      /* one record per line */
STYLE_MASK      = STYLE_SINGLE,

/* 51306 lrwxrwxrwx  1 root     root         2 May 11 01:43 /bin/view -> vi* */
/* what file information will be listed */
LIST_INO        = 1 << 0,
LIST_BLOCKS     = 1 << 1,
LIST_MODEBITS   = 1 << 2,
LIST_NLINKS     = 1 << 3,
LIST_ID_NAME    = 1 << 4,
LIST_ID_NUMERIC = 1 << 5,
LIST_CONTEXT    = 1 << 6,
LIST_SIZE       = 1 << 7,
//LIST_DEV        = 1 << 8, - unused, synonym to LIST_SIZE
LIST_DATE_TIME  = 1 << 9,
LIST_FULLTIME   = 1 << 10,
LIST_FILENAME   = 1 << 11,
LIST_SYMLINK    = 1 << 12,
LIST_FILETYPE   = 1 << 13,
LIST_EXEC       = 1 << 14,
LIST_MASK       = (LIST_EXEC << 1) - 1,

/* what files will be displayed */
DISP_DIRNAME    = 1 << 15,      /* 2 or more items? label directories */
DISP_HIDDEN     = 1 << 16,      /* show filenames starting with . */
DISP_DOT        = 1 << 17,      /* show . and .. */
DISP_NOLIST     = 1 << 18,      /* show directory as itself, not contents */
DISP_RECURSIVE  = 1 << 19,      /* show directory and everything below it */
DISP_ROWS       = 1 << 20,      /* print across rows */
DISP_MASK       = ((DISP_ROWS << 1) - 1) & ~(DISP_DIRNAME - 1),

/* how will the files be sorted (CONFIG_FEATURE_LS_SORTFILES) */
SORT_FORWARD    = 0,            /* sort in reverse order */
SORT_REVERSE    = 1 << 27,      /* sort in reverse order */

SORT_NAME       = 0,            /* sort by file name */
SORT_SIZE       = 1 << 28,      /* sort by file size */
SORT_ATIME      = 2 << 28,      /* sort by last access time */
SORT_CTIME      = 3 << 28,      /* sort by last change time */
SORT_MTIME      = 4 << 28,      /* sort by last modification time */
SORT_VERSION    = 5 << 28,      /* sort by version */
SORT_EXT        = 6 << 28,      /* sort by file name extension */
SORT_DIR        = 7 << 28,      /* sort by file or directory */
SORT_MASK       = (7 << 28) * ENABLE_FEATURE_LS_SORTFILES,

/* which of the three times will be used */
TIME_CHANGE     = (1 << 23) * ENABLE_FEATURE_LS_TIMESTAMPS,
TIME_ACCESS     = (1 << 24) * ENABLE_FEATURE_LS_TIMESTAMPS,
TIME_MASK       = (3 << 23) * ENABLE_FEATURE_LS_TIMESTAMPS,

FOLLOW_LINKS    = (1 << 25) * ENABLE_FEATURE_LS_FOLLOWLINKS,

LS_DISP_HR      = (1 << 26) * ENABLE_FEATURE_HUMAN_READABLE,

LIST_SHORT      = LIST_FILENAME,
LIST_LONG       = LIST_MODEBITS | LIST_NLINKS | LIST_ID_NAME | LIST_SIZE | \
                  LIST_DATE_TIME | LIST_FILENAME | LIST_SYMLINK,

SPLIT_DIR       = 1,
SPLIT_FILE      = 0,
SPLIT_SUBDIR    = 2,
};

/* "[-]Cadil1", POSIX mandated options, busybox always supports */
/* "[-]gnsx", POSIX non-mandated options, busybox always supports */
/* "[-]Q" GNU option? busybox always supports */
/* "[-]Ak" GNU options, busybox always supports */
/* "[-]FLRctur", POSIX mandated options, busybox optionally supports */
/* "[-]p", POSIX non-mandated options, busybox optionally supports */
/* "[-]SXvThw", GNU options, busybox optionally supports */
/* "[-]K", SELinux mandated options, busybox optionally supports */
/* "[-]e", I think we made this one up */
static const char ls_options[] ALIGN1 =
	"Cadil1gnsxQAk" /* 13 opts, total 13 */
	IF_FEATURE_LS_TIMESTAMPS("cetu") /* 4, 17 */
	IF_FEATURE_LS_SORTFILES("SXrv")  /* 4, 21 */
	IF_FEATURE_LS_FILETYPES("Fp")    /* 2, 23 */
	IF_FEATURE_LS_FOLLOWLINKS("L")   /* 1, 24 */
	IF_FEATURE_LS_RECURSIVE("R")     /* 1, 25 */
	IF_FEATURE_HUMAN_READABLE("h")   /* 1, 26 */
	IF_SELINUX("KZ") /* 2, 28 */
	IF_FEATURE_AUTOWIDTH("T:w:") /* 2, 30 */
	;
enum {
	//OPT_C = (1 << 0),
	//OPT_a = (1 << 1),
	//OPT_d = (1 << 2),
	//OPT_i = (1 << 3),
	//OPT_l = (1 << 4),
	//OPT_1 = (1 << 5),
	OPT_g = (1 << 6),
	//OPT_n = (1 << 7),
	//OPT_s = (1 << 8),
	//OPT_x = (1 << 9),
	OPT_Q = (1 << 10),
	//OPT_A = (1 << 11),
	//OPT_k = (1 << 12),
	OPTBIT_color = 13
		+ 4 * ENABLE_FEATURE_LS_TIMESTAMPS
		+ 4 * ENABLE_FEATURE_LS_SORTFILES
		+ 2 * ENABLE_FEATURE_LS_FILETYPES
		+ 1 * ENABLE_FEATURE_LS_FOLLOWLINKS
		+ 1 * ENABLE_FEATURE_LS_RECURSIVE
		+ 1 * ENABLE_FEATURE_HUMAN_READABLE
		+ 2 * ENABLE_SELINUX
		+ 2 * ENABLE_FEATURE_AUTOWIDTH,
	OPT_color = 1 << OPTBIT_color,
};

enum {
	LIST_MASK_TRIGGER	= 0,
	STYLE_MASK_TRIGGER	= STYLE_MASK,
	DISP_MASK_TRIGGER	= DISP_ROWS,
	SORT_MASK_TRIGGER	= SORT_MASK,
};

/* TODO: simple toggles may be stored as OPT_xxx bits instead */
static const unsigned opt_flags[] = {
	LIST_SHORT | STYLE_COLUMNS, /* C */
	DISP_HIDDEN | DISP_DOT,     /* a */
	DISP_NOLIST,                /* d */
	LIST_INO,                   /* i */
	LIST_LONG | STYLE_LONG,     /* l - remember LS_DISP_HR in mask! */
	LIST_SHORT | STYLE_SINGLE,  /* 1 */
	0,                          /* g (don't show owner) - handled via OPT_g */
	LIST_ID_NUMERIC,            /* n */
	LIST_BLOCKS,                /* s */
	DISP_ROWS,                  /* x */
	0,                          /* Q (quote filename) - handled via OPT_Q */
	DISP_HIDDEN,                /* A */
	ENABLE_SELINUX * LIST_CONTEXT, /* k (ignored if !SELINUX) */
#if ENABLE_FEATURE_LS_TIMESTAMPS
	TIME_CHANGE | (ENABLE_FEATURE_LS_SORTFILES * SORT_CTIME),   /* c */
	LIST_FULLTIME,              /* e */
	ENABLE_FEATURE_LS_SORTFILES * SORT_MTIME,   /* t */
	TIME_ACCESS | (ENABLE_FEATURE_LS_SORTFILES * SORT_ATIME),   /* u */
#endif
#if ENABLE_FEATURE_LS_SORTFILES
	SORT_SIZE,                  /* S */
	SORT_EXT,                   /* X */
	SORT_REVERSE,               /* r */
	SORT_VERSION,               /* v */
#endif
#if ENABLE_FEATURE_LS_FILETYPES
	LIST_FILETYPE | LIST_EXEC,  /* F */
	LIST_FILETYPE,              /* p */
#endif
#if ENABLE_FEATURE_LS_FOLLOWLINKS
	FOLLOW_LINKS,               /* L */
#endif
#if ENABLE_FEATURE_LS_RECURSIVE
	DISP_RECURSIVE,             /* R */
#endif
#if ENABLE_FEATURE_HUMAN_READABLE
	LS_DISP_HR,                 /* h */
#endif
#if ENABLE_SELINUX
	LIST_MODEBITS|LIST_NLINKS|LIST_CONTEXT|LIST_SIZE|LIST_DATE_TIME, /* K */
#endif
#if ENABLE_SELINUX
	LIST_MODEBITS|LIST_ID_NAME|LIST_CONTEXT, /* Z */
#endif
	(1U<<31)
	/* options after Z are not processed through opt_flags:
	 * T, w - ignored
	 */
};


/*
 * a directory entry and its stat info are stored here
 */
struct dnode {
	const char *name;       /* the dir entry name */
	const char *fullname;   /* the dir entry name */
	struct dnode *next;     /* point at the next node */
	smallint fname_allocated;
	struct stat dstat;      /* the file stat info */
	IF_SELINUX(security_context_t sid;)
};

struct globals {
#if ENABLE_FEATURE_LS_COLOR
	smallint show_color;
#endif
	smallint exit_code;
	unsigned all_fmt;
#if ENABLE_FEATURE_AUTOWIDTH
	unsigned tabstops; // = COLUMN_GAP;
	unsigned terminal_width; // = TERMINAL_WIDTH;
#endif
#if ENABLE_FEATURE_LS_TIMESTAMPS
	/* Do time() just once. Saves one syscall per file for "ls -l" */
	time_t current_time_t;
#endif
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#if ENABLE_FEATURE_LS_COLOR
# define show_color     (G.show_color    )
#else
enum { show_color = 0 };
#endif
#define exit_code       (G.exit_code     )
#define all_fmt         (G.all_fmt       )
#if ENABLE_FEATURE_AUTOWIDTH
# define tabstops       (G.tabstops      )
# define terminal_width (G.terminal_width)
#else
enum {
	tabstops = COLUMN_GAP,
	terminal_width = TERMINAL_WIDTH,
};
#endif
#define current_time_t (G.current_time_t)
#define INIT_G() do { \
	/* we have to zero it out because of NOEXEC */ \
	memset(&G, 0, sizeof(G)); \
	IF_FEATURE_AUTOWIDTH(tabstops = COLUMN_GAP;) \
	IF_FEATURE_AUTOWIDTH(terminal_width = TERMINAL_WIDTH;) \
	IF_FEATURE_LS_TIMESTAMPS(time(&current_time_t);) \
} while (0)


static struct dnode *my_stat(const char *fullname, const char *name, int force_follow)
{
	struct stat dstat;
	struct dnode *cur;
	IF_SELINUX(security_context_t sid = NULL;)

	if ((all_fmt & FOLLOW_LINKS) || force_follow) {
#if ENABLE_SELINUX
		if (is_selinux_enabled())  {
			 getfilecon(fullname, &sid);
		}
#endif
		if (stat(fullname, &dstat)) {
			bb_simple_perror_msg(fullname);
			exit_code = EXIT_FAILURE;
			return 0;
		}
	} else {
#if ENABLE_SELINUX
		if (is_selinux_enabled()) {
			lgetfilecon(fullname, &sid);
		}
#endif
		if (lstat(fullname, &dstat)) {
			bb_simple_perror_msg(fullname);
			exit_code = EXIT_FAILURE;
			return 0;
		}
	}

	cur = xmalloc(sizeof(*cur));
	cur->fullname = fullname;
	cur->name = name;
	cur->dstat = dstat;
	IF_SELINUX(cur->sid = sid;)
	return cur;
}

/* FYI type values: 1:fifo 2:char 4:dir 6:blk 8:file 10:link 12:socket
 * (various wacky OSes: 13:Sun door 14:BSD whiteout 5:XENIX named file
 *  3/7:multiplexed char/block device)
 * and we use 0 for unknown and 15 for executables (see below) */
#define TYPEINDEX(mode) (((mode) >> 12) & 0x0f)
#define TYPECHAR(mode)  ("0pcCd?bB-?l?s???" [TYPEINDEX(mode)])
#define APPCHAR(mode)   ("\0|\0\0/\0\0\0\0\0@\0=\0\0\0" [TYPEINDEX(mode)])
/* 036 black foreground              050 black background
   037 red foreground                051 red background
   040 green foreground              052 green background
   041 brown foreground              053 brown background
   042 blue foreground               054 blue background
   043 magenta (purple) foreground   055 magenta background
   044 cyan (light blue) foreground  056 cyan background
   045 gray foreground               057 white background
*/
#define COLOR(mode) ( \
	/*un  fi  chr     dir     blk     file    link    sock        exe */ \
	"\037\043\043\045\042\045\043\043\000\045\044\045\043\045\045\040" \
	[TYPEINDEX(mode)])
/* Select normal (0) [actually "reset all"] or bold (1)
 * (other attributes are 2:dim 4:underline 5:blink 7:reverse,
 *  let's use 7 for "impossible" types, just for fun)
 * Note: coreutils 6.9 uses inverted red for setuid binaries.
 */
#define ATTR(mode) ( \
	/*un fi chr   dir   blk   file  link  sock     exe */ \
	"\01\00\01\07\01\07\01\07\00\07\01\07\01\07\07\01" \
	[TYPEINDEX(mode)])

#if ENABLE_FEATURE_LS_COLOR
/* mode of zero is interpreted as "unknown" (stat failed) */
static char fgcolor(mode_t mode)
{
	if (S_ISREG(mode) && (mode & (S_IXUSR | S_IXGRP | S_IXOTH)))
		return COLOR(0xF000);	/* File is executable ... */
	return COLOR(mode);
}
static char bold(mode_t mode)
{
	if (S_ISREG(mode) && (mode & (S_IXUSR | S_IXGRP | S_IXOTH)))
		return ATTR(0xF000);	/* File is executable ... */
	return ATTR(mode);
}
#endif

#if ENABLE_FEATURE_LS_FILETYPES || ENABLE_FEATURE_LS_COLOR
static char append_char(mode_t mode)
{
	if (!(all_fmt & LIST_FILETYPE))
		return '\0';
	if (S_ISDIR(mode))
		return '/';
	if (!(all_fmt & LIST_EXEC))
		return '\0';
	if (S_ISREG(mode) && (mode & (S_IXUSR | S_IXGRP | S_IXOTH)))
		return '*';
	return APPCHAR(mode);
}
#endif

static unsigned count_dirs(struct dnode **dn, int which)
{
	unsigned dirs, all;

	if (!dn)
		return 0;

	dirs = all = 0;
	for (; *dn; dn++) {
		const char *name;

		all++;
		if (!S_ISDIR((*dn)->dstat.st_mode))
			continue;
		name = (*dn)->name;
		if (which != SPLIT_SUBDIR /* if not requested to skip . / .. */
		 /* or if it's not . or .. */
		 || name[0] != '.' || (name[1] && (name[1] != '.' || name[2]))
		) {
			dirs++;
		}
	}
	return which != SPLIT_FILE ? dirs : all - dirs;
}

/* get memory to hold an array of pointers */
static struct dnode **dnalloc(unsigned num)
{
	if (num < 1)
		return NULL;

	num++; /* so that we have terminating NULL */
	return xzalloc(num * sizeof(struct dnode *));
}

#if ENABLE_FEATURE_LS_RECURSIVE
static void dfree(struct dnode **dnp)
{
	unsigned i;

	if (dnp == NULL)
		return;

	for (i = 0; dnp[i]; i++) {
		struct dnode *cur = dnp[i];
		if (cur->fname_allocated)
			free((char*)cur->fullname);
		free(cur);
	}
	free(dnp);
}
#else
#define dfree(...) ((void)0)
#endif

/* Returns NULL-terminated malloced vector of pointers (or NULL) */
static struct dnode **splitdnarray(struct dnode **dn, int which)
{
	unsigned dncnt, d;
	struct dnode **dnp;

	if (dn == NULL)
		return NULL;

	/* count how many dirs or files there are */
	dncnt = count_dirs(dn, which);

	/* allocate a file array and a dir array */
	dnp = dnalloc(dncnt);

	/* copy the entrys into the file or dir array */
	for (d = 0; *dn; dn++) {
		if (S_ISDIR((*dn)->dstat.st_mode)) {
			const char *name;

			if (!(which & (SPLIT_DIR|SPLIT_SUBDIR)))
				continue;
			name = (*dn)->name;
			if ((which & SPLIT_DIR)
			 || name[0]!='.' || (name[1] && (name[1]!='.' || name[2]))
			) {
				dnp[d++] = *dn;
			}
		} else if (!(which & (SPLIT_DIR|SPLIT_SUBDIR))) {
			dnp[d++] = *dn;
		}
	}
	return dnp;
}

#if ENABLE_FEATURE_LS_SORTFILES
static int sortcmp(const void *a, const void *b)
{
	struct dnode *d1 = *(struct dnode **)a;
	struct dnode *d2 = *(struct dnode **)b;
	unsigned sort_opts = all_fmt & SORT_MASK;
	off_t dif;

	dif = 0; /* assume SORT_NAME */
	// TODO: use pre-initialized function pointer
	// instead of branch forest
	if (sort_opts == SORT_SIZE) {
		dif = (d2->dstat.st_size - d1->dstat.st_size);
	} else if (sort_opts == SORT_ATIME) {
		dif = (d2->dstat.st_atime - d1->dstat.st_atime);
	} else if (sort_opts == SORT_CTIME) {
		dif = (d2->dstat.st_ctime - d1->dstat.st_ctime);
	} else if (sort_opts == SORT_MTIME) {
		dif = (d2->dstat.st_mtime - d1->dstat.st_mtime);
	} else if (sort_opts == SORT_DIR) {
		dif = S_ISDIR(d2->dstat.st_mode) - S_ISDIR(d1->dstat.st_mode);
		/* } else if (sort_opts == SORT_VERSION) { */
		/* } else if (sort_opts == SORT_EXT) { */
	}
	if (dif == 0) {
		/* sort by name, or tie_breaker for other sorts */
		if (ENABLE_LOCALE_SUPPORT)
			dif = strcoll(d1->name, d2->name);
		else
			dif = strcmp(d1->name, d2->name);
	}

	/* Make dif fit into an int */
	if (sizeof(dif) > sizeof(int)) {
		enum { BITS_TO_SHIFT = 8 * (sizeof(dif) - sizeof(int)) };
		/* shift leaving only "int" worth of bits */
		if (dif != 0) {
			dif = 1 | (int)((uoff_t)dif >> BITS_TO_SHIFT);
		}
	}

	return (all_fmt & SORT_REVERSE) ? -(int)dif : (int)dif;
}

static void dnsort(struct dnode **dn, int size)
{
	qsort(dn, size, sizeof(*dn), sortcmp);
}
#else
#define dnsort(dn, size) ((void)0)
#endif


static unsigned calc_name_len(const char *name)
{
	unsigned len;
	uni_stat_t uni_stat;

	// TODO: quote tab as \t, etc, if -Q
	name = printable_string(&uni_stat, name);

	if (!(option_mask32 & OPT_Q)) {
		return uni_stat.unicode_width;
	}

	len = 2 + uni_stat.unicode_width;
	while (*name) {
		if (*name == '"' || *name == '\\') {
			len++;
		}
		name++;
	}
	return len;
}


/* Return the number of used columns.
 * Note that only STYLE_COLUMNS uses return value.
 * STYLE_SINGLE and STYLE_LONG don't care.
 * coreutils 7.2 also supports:
 * ls -b (--escape) = octal escapes (although it doesn't look like working)
 * ls -N (--literal) = not escape at all
 */
static unsigned print_name(const char *name)
{
	unsigned len;
	uni_stat_t uni_stat;

	// TODO: quote tab as \t, etc, if -Q
	name = printable_string(&uni_stat, name);

	if (!(option_mask32 & OPT_Q)) {
		fputs(name, stdout);
		return uni_stat.unicode_width;
	}

	len = 2 + uni_stat.unicode_width;
	putchar('"');
	while (*name) {
		if (*name == '"' || *name == '\\') {
			putchar('\\');
			len++;
		}
		putchar(*name);
		name++;
	}
	putchar('"');
	return len;
}

/* Return the number of used columns.
 * Note that only STYLE_COLUMNS uses return value,
 * STYLE_SINGLE and STYLE_LONG don't care.
 */
static NOINLINE unsigned list_single(const struct dnode *dn)
{
	unsigned column = 0;
	char *lpath = lpath; /* for compiler */
#if ENABLE_FEATURE_LS_FILETYPES || ENABLE_FEATURE_LS_COLOR
	struct stat info;
	char append;
#endif

	/* Never happens:
	if (dn->fullname == NULL)
		return 0;
	*/

#if ENABLE_FEATURE_LS_FILETYPES
	append = append_char(dn->dstat.st_mode);
#endif

	/* Do readlink early, so that if it fails, error message
	 * does not appear *inside* the "ls -l" line */
	if (all_fmt & LIST_SYMLINK)
		if (S_ISLNK(dn->dstat.st_mode))
			lpath = xmalloc_readlink_or_warn(dn->fullname);

	if (all_fmt & LIST_INO)
		column += printf("%7llu ", (long long) dn->dstat.st_ino);
	if (all_fmt & LIST_BLOCKS)
		column += printf("%4"OFF_FMT"u ", (off_t) (dn->dstat.st_blocks >> 1));
	if (all_fmt & LIST_MODEBITS)
		column += printf("%-10s ", (char *) bb_mode_string(dn->dstat.st_mode));
	if (all_fmt & LIST_NLINKS)
		column += printf("%4lu ", (long) dn->dstat.st_nlink);
#if ENABLE_FEATURE_LS_USERNAME
	if (all_fmt & LIST_ID_NAME) {
		if (option_mask32 & OPT_g) {
			column += printf("%-8.8s ",
				get_cached_groupname(dn->dstat.st_gid));
		} else {
			column += printf("%-8.8s %-8.8s ",
				get_cached_username(dn->dstat.st_uid),
				get_cached_groupname(dn->dstat.st_gid));
		}
	}
#endif
	if (all_fmt & LIST_ID_NUMERIC) {
		if (option_mask32 & OPT_g)
			column += printf("%-8u ", (int) dn->dstat.st_gid);
		else
			column += printf("%-8u %-8u ",
					(int) dn->dstat.st_uid,
					(int) dn->dstat.st_gid);
	}
	if (all_fmt & (LIST_SIZE /*|LIST_DEV*/ )) {
		if (S_ISBLK(dn->dstat.st_mode) || S_ISCHR(dn->dstat.st_mode)) {
			column += printf("%4u, %3u ",
					(int) major(dn->dstat.st_rdev),
					(int) minor(dn->dstat.st_rdev));
		} else {
			if (all_fmt & LS_DISP_HR) {
				column += printf("%"HUMAN_READABLE_MAX_WIDTH_STR"s ",
					/* print st_size, show one fractional, use suffixes */
					make_human_readable_str(dn->dstat.st_size, 1, 0)
				);
			} else {
				column += printf("%9"OFF_FMT"u ", (off_t) dn->dstat.st_size);
			}
		}
	}
#if ENABLE_FEATURE_LS_TIMESTAMPS
	if (all_fmt & (LIST_FULLTIME|LIST_DATE_TIME)) {
		char *filetime;
		time_t ttime = dn->dstat.st_mtime;
		if (all_fmt & TIME_ACCESS)
			ttime = dn->dstat.st_atime;
		if (all_fmt & TIME_CHANGE)
			ttime = dn->dstat.st_ctime;
		filetime = ctime(&ttime);
		/* filetime's format: "Wed Jun 30 21:49:08 1993\n" */
		if (all_fmt & LIST_FULLTIME)
			column += printf("%.24s ", filetime);
		else { /* LIST_DATE_TIME */
			/* current_time_t ~== time(NULL) */
			time_t age = current_time_t - ttime;
			printf("%.6s ", filetime + 4); /* "Jun 30" */
			if (age < 3600L * 24 * 365 / 2 && age > -15 * 60) {
				/* hh:mm if less than 6 months old */
				printf("%.5s ", filetime + 11);
			} else { /* year. buggy if year > 9999 ;) */
				printf(" %.4s ", filetime + 20);
			}
			column += 13;
		}
	}
#endif
#if ENABLE_SELINUX
	if (all_fmt & LIST_CONTEXT) {
		column += printf("%-32s ", dn->sid ? dn->sid : "unknown");
		freecon(dn->sid);
	}
#endif
	if (all_fmt & LIST_FILENAME) {
#if ENABLE_FEATURE_LS_COLOR
		if (show_color) {
			info.st_mode = 0; /* for fgcolor() */
			lstat(dn->fullname, &info);
			printf("\033[%u;%um", bold(info.st_mode),
					fgcolor(info.st_mode));
		}
#endif
		column += print_name(dn->name);
		if (show_color) {
			printf("\033[0m");
		}
	}
	if (all_fmt & LIST_SYMLINK) {
		if (S_ISLNK(dn->dstat.st_mode) && lpath) {
			printf(" -> ");
#if ENABLE_FEATURE_LS_FILETYPES || ENABLE_FEATURE_LS_COLOR
#if ENABLE_FEATURE_LS_COLOR
			info.st_mode = 0; /* for fgcolor() */
#endif
			if (stat(dn->fullname, &info) == 0) {
				append = append_char(info.st_mode);
			}
#endif
#if ENABLE_FEATURE_LS_COLOR
			if (show_color) {
				printf("\033[%u;%um", bold(info.st_mode),
					   fgcolor(info.st_mode));
			}
#endif
			column += print_name(lpath) + 4;
			if (show_color) {
				printf("\033[0m");
			}
			free(lpath);
		}
	}
#if ENABLE_FEATURE_LS_FILETYPES
	if (all_fmt & LIST_FILETYPE) {
		if (append) {
			putchar(append);
			column++;
		}
	}
#endif

	return column;
}

static void showfiles(struct dnode **dn, unsigned nfiles)
{
	unsigned i, ncols, nrows, row, nc;
	unsigned column = 0;
	unsigned nexttab = 0;
	unsigned column_width = 0; /* used only by STYLE_COLUMNS */

	if (all_fmt & STYLE_LONG) { /* STYLE_LONG or STYLE_SINGLE */
		ncols = 1;
	} else {
		/* find the longest file name, use that as the column width */
		for (i = 0; dn[i]; i++) {
			int len = calc_name_len(dn[i]->name);
			if (column_width < len)
				column_width = len;
		}
		column_width += tabstops +
			IF_SELINUX( ((all_fmt & LIST_CONTEXT) ? 33 : 0) + )
				((all_fmt & LIST_INO) ? 8 : 0) +
				((all_fmt & LIST_BLOCKS) ? 5 : 0);
		ncols = (int) (terminal_width / column_width);
	}

	if (ncols > 1) {
		nrows = nfiles / ncols;
		if (nrows * ncols < nfiles)
			nrows++;                /* round up fractionals */
	} else {
		nrows = nfiles;
		ncols = 1;
	}

	for (row = 0; row < nrows; row++) {
		for (nc = 0; nc < ncols; nc++) {
			/* reach into the array based on the column and row */
			if (all_fmt & DISP_ROWS)
				i = (row * ncols) + nc;	/* display across row */
			else
				i = (nc * nrows) + row;	/* display by column */
			if (i < nfiles) {
				if (column > 0) {
					nexttab -= column;
					printf("%*s", nexttab, "");
					column += nexttab;
				}
				nexttab = column + column_width;
				column += list_single(dn[i]);
			}
		}
		putchar('\n');
		column = 0;
	}
}


#if ENABLE_DESKTOP
/* http://www.opengroup.org/onlinepubs/9699919799/utilities/ls.html
 * If any of the -l, -n, -s options is specified, each list
 * of files within the directory shall be preceded by a
 * status line indicating the number of file system blocks
 * occupied by files in the directory in 512-byte units if
 * the -k option is not specified, or 1024-byte units if the
 * -k option is specified, rounded up to the next integral
 * number of units.
 */
/* by Jorgen Overgaard (jorgen AT antistaten.se) */
static off_t calculate_blocks(struct dnode **dn)
{
	uoff_t blocks = 1;
	if (dn) {
		while (*dn) {
			/* st_blocks is in 512 byte blocks */
			blocks += (*dn)->dstat.st_blocks;
			dn++;
		}
	}

	/* Even though standard says use 512 byte blocks, coreutils use 1k */
	/* Actually, we round up by calculating (blocks + 1) / 2,
	 * "+ 1" was done when we initialized blocks to 1 */
	return blocks >> 1;
}
#endif


static struct dnode **list_dir(const char *, unsigned *);

static void showdirs(struct dnode **dn, int first)
{
	unsigned nfiles;
	unsigned dndirs;
	struct dnode **subdnp;
	struct dnode **dnd;

	/* Never happens:
	if (dn == NULL || ndirs < 1) {
		return;
	}
	*/

	for (; *dn; dn++) {
		if (all_fmt & (DISP_DIRNAME | DISP_RECURSIVE)) {
			if (!first)
				bb_putchar('\n');
			first = 0;
			printf("%s:\n", (*dn)->fullname);
		}
		subdnp = list_dir((*dn)->fullname, &nfiles);
#if ENABLE_DESKTOP
		if ((all_fmt & STYLE_MASK) == STYLE_LONG)
			printf("total %"OFF_FMT"u\n", calculate_blocks(subdnp));
#endif
		if (nfiles > 0) {
			/* list all files at this level */
			dnsort(subdnp, nfiles);
			showfiles(subdnp, nfiles);
			if (ENABLE_FEATURE_LS_RECURSIVE
			 && (all_fmt & DISP_RECURSIVE)
			) {
				/* recursive - list the sub-dirs */
				dnd = splitdnarray(subdnp, SPLIT_SUBDIR);
				dndirs = count_dirs(subdnp, SPLIT_SUBDIR);
				if (dndirs > 0) {
					dnsort(dnd, dndirs);
					showdirs(dnd, 0);
					/* free the array of dnode pointers to the dirs */
					free(dnd);
				}
			}
			/* free the dnodes and the fullname mem */
			dfree(subdnp);
		}
	}
}


/* Returns NULL-terminated malloced vector of pointers (or NULL) */
static struct dnode **list_dir(const char *path, unsigned *nfiles_p)
{
	struct dnode *dn, *cur, **dnp;
	struct dirent *entry;
	DIR *dir;
	unsigned i, nfiles;

	/* Never happens:
	if (path == NULL)
		return NULL;
	*/

	*nfiles_p = 0;
	dir = warn_opendir(path);
	if (dir == NULL) {
		exit_code = EXIT_FAILURE;
		return NULL;	/* could not open the dir */
	}
	dn = NULL;
	nfiles = 0;
	while ((entry = readdir(dir)) != NULL) {
		char *fullname;

		/* are we going to list the file- it may be . or .. or a hidden file */
		if (entry->d_name[0] == '.') {
			if ((!entry->d_name[1] || (entry->d_name[1] == '.' && !entry->d_name[2]))
			 && !(all_fmt & DISP_DOT)
			) {
				continue;
			}
			if (!(all_fmt & DISP_HIDDEN))
				continue;
		}
		fullname = concat_path_file(path, entry->d_name);
		cur = my_stat(fullname, bb_basename(fullname), 0);
		if (!cur) {
			free(fullname);
			continue;
		}
		cur->fname_allocated = 1;
		cur->next = dn;
		dn = cur;
		nfiles++;
	}
	closedir(dir);

	if (dn == NULL)
		return NULL;

	/* now that we know how many files there are
	 * allocate memory for an array to hold dnode pointers
	 */
	*nfiles_p = nfiles;
	dnp = dnalloc(nfiles);
	for (i = 0; /* i < nfiles - detected via !dn below */; i++) {
		dnp[i] = dn;	/* save pointer to node in array */
		dn = dn->next;
		if (!dn)
			break;
	}

	return dnp;
}


int ls_main(int argc UNUSED_PARAM, char **argv)
{
	struct dnode **dnd;
	struct dnode **dnf;
	struct dnode **dnp;
	struct dnode *dn;
	struct dnode *cur;
	unsigned opt;
	unsigned nfiles;
	unsigned dnfiles;
	unsigned dndirs;
	unsigned i;
#if ENABLE_FEATURE_LS_COLOR
	/* colored LS support by JaWi, janwillem.janssen@lxtreme.nl */
	/* coreutils 6.10:
	 * # ls --color=BOGUS
	 * ls: invalid argument 'BOGUS' for '--color'
	 * Valid arguments are:
	 * 'always', 'yes', 'force'
	 * 'never', 'no', 'none'
	 * 'auto', 'tty', 'if-tty'
	 * (and substrings: "--color=alwa" work too)
	 */
	static const char ls_longopts[] ALIGN1 =
		"color\0" Optional_argument "\xff"; /* no short equivalent */
	static const char color_str[] ALIGN1 =
		"always\0""yes\0""force\0"
		"auto\0""tty\0""if-tty\0";
	/* need to initialize since --color has _an optional_ argument */
	const char *color_opt = color_str; /* "always" */
#endif

	INIT_G();

	init_unicode();

	all_fmt = LIST_SHORT |
		(ENABLE_FEATURE_LS_SORTFILES * (SORT_NAME | SORT_FORWARD));

#if ENABLE_FEATURE_AUTOWIDTH
	/* obtain the terminal width */
	get_terminal_width_height(STDIN_FILENO, &terminal_width, NULL);
	/* go one less... */
	terminal_width--;
#endif

	/* process options */
	IF_FEATURE_LS_COLOR(applet_long_options = ls_longopts;)
#if ENABLE_FEATURE_AUTOWIDTH
	opt_complementary = "T+:w+"; /* -T N, -w N */
	opt = getopt32(argv, ls_options, &tabstops, &terminal_width
				IF_FEATURE_LS_COLOR(, &color_opt));
#else
	opt = getopt32(argv, ls_options IF_FEATURE_LS_COLOR(, &color_opt));
#endif
	for (i = 0; opt_flags[i] != (1U<<31); i++) {
		if (opt & (1 << i)) {
			unsigned flags = opt_flags[i];

			if (flags & LIST_MASK_TRIGGER)
				all_fmt &= ~LIST_MASK;
			if (flags & STYLE_MASK_TRIGGER)
				all_fmt &= ~STYLE_MASK;
			if (flags & SORT_MASK_TRIGGER)
				all_fmt &= ~SORT_MASK;
			if (flags & DISP_MASK_TRIGGER)
				all_fmt &= ~DISP_MASK;
			if (flags & TIME_MASK)
				all_fmt &= ~TIME_MASK;
			if (flags & LIST_CONTEXT)
				all_fmt |= STYLE_SINGLE;
			/* huh?? opt cannot be 'l' */
			//if (LS_DISP_HR && opt == 'l')
			//	all_fmt &= ~LS_DISP_HR;
			all_fmt |= flags;
		}
	}

#if ENABLE_FEATURE_LS_COLOR
	/* find color bit value - last position for short getopt */
	if (ENABLE_FEATURE_LS_COLOR_IS_DEFAULT && isatty(STDOUT_FILENO)) {
		char *p = getenv("LS_COLORS");
		/* LS_COLORS is unset, or (not empty && not "none") ? */
		if (!p || (p[0] && strcmp(p, "none") != 0))
			show_color = 1;
	}
	if (opt & OPT_color) {
		if (color_opt[0] == 'n')
			show_color = 0;
		else switch (index_in_substrings(color_str, color_opt)) {
		case 3:
		case 4:
		case 5:
			if (isatty(STDOUT_FILENO)) {
		case 0:
		case 1:
		case 2:
				show_color = 1;
			}
		}
	}
#endif

	/* sort out which command line options take precedence */
	if (ENABLE_FEATURE_LS_RECURSIVE && (all_fmt & DISP_NOLIST))
		all_fmt &= ~DISP_RECURSIVE;	/* no recurse if listing only dir */
	if (ENABLE_FEATURE_LS_TIMESTAMPS && ENABLE_FEATURE_LS_SORTFILES) {
		if (all_fmt & TIME_CHANGE)
			all_fmt = (all_fmt & ~SORT_MASK) | SORT_CTIME;
		if (all_fmt & TIME_ACCESS)
			all_fmt = (all_fmt & ~SORT_MASK) | SORT_ATIME;
	}
	if ((all_fmt & STYLE_MASK) != STYLE_LONG) /* only for long list */
		all_fmt &= ~(LIST_ID_NUMERIC|LIST_FULLTIME|LIST_ID_NAME|LIST_ID_NUMERIC);
	if (ENABLE_FEATURE_LS_USERNAME)
		if ((all_fmt & STYLE_MASK) == STYLE_LONG && (all_fmt & LIST_ID_NUMERIC))
			all_fmt &= ~LIST_ID_NAME; /* don't list names if numeric uid */

	/* choose a display format */
	if (!(all_fmt & STYLE_MASK))
		all_fmt |= (isatty(STDOUT_FILENO) ? STYLE_COLUMNS : STYLE_SINGLE);

	argv += optind;
	if (!argv[0])
		*--argv = (char*)".";

	if (argv[1])
		all_fmt |= DISP_DIRNAME; /* 2 or more items? label directories */

	/* stuff the command line file names into a dnode array */
	dn = NULL;
	nfiles = 0;
	do {
		/* NB: follow links on command line unless -l or -s */
		cur = my_stat(*argv, *argv, !(all_fmt & (STYLE_LONG|LIST_BLOCKS)));
		argv++;
		if (!cur)
			continue;
		cur->fname_allocated = 0;
		cur->next = dn;
		dn = cur;
		nfiles++;
	} while (*argv);

	/* nfiles _may_ be 0 here - try "ls doesnt_exist" */
	if (nfiles == 0)
		return exit_code;

	/* now that we know how many files there are
	 * allocate memory for an array to hold dnode pointers
	 */
	dnp = dnalloc(nfiles);
	for (i = 0; /* i < nfiles - detected via !dn below */; i++) {
		dnp[i] = dn;	/* save pointer to node in array */
		dn = dn->next;
		if (!dn)
			break;
	}

	if (all_fmt & DISP_NOLIST) {
		dnsort(dnp, nfiles);
		showfiles(dnp, nfiles);
	} else {
		dnd = splitdnarray(dnp, SPLIT_DIR);
		dnf = splitdnarray(dnp, SPLIT_FILE);
		dndirs = count_dirs(dnp, SPLIT_DIR);
		dnfiles = nfiles - dndirs;
		if (dnfiles > 0) {
			dnsort(dnf, dnfiles);
			showfiles(dnf, dnfiles);
			if (ENABLE_FEATURE_CLEAN_UP)
				free(dnf);
		}
		if (dndirs > 0) {
			dnsort(dnd, dndirs);
			showdirs(dnd, dnfiles == 0);
			if (ENABLE_FEATURE_CLEAN_UP)
				free(dnd);
		}
	}
	if (ENABLE_FEATURE_CLEAN_UP)
		dfree(dnp);
	return exit_code;
}