aboutsummaryrefslogtreecommitdiff
path: root/archival/tar.c
blob: b6d5129d82b02bc545c076b16c331f3d6a288239 (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
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
/* vi: set sw=4 ts=4: */
/*
 * Mini tar implementation for busybox
 *
 * Modified to use common extraction code used by ar, cpio, dpkg-deb, dpkg
 *  by Glenn McGrath
 *
 * Note, that as of BusyBox-0.43, tar has been completely rewritten from the
 * ground up.  It still has remnants of the old code lying about, but it is
 * very different now (i.e., cleaner, less global variables, etc.)
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 *
 * Based in part in the tar implementation in sash
 *  Copyright (c) 1999 by David I. Bell
 *  Permission is granted to use, distribute, or modify this source,
 *  provided that this copyright notice remains intact.
 *  Permission to distribute sash derived code under GPL has been granted.
 *
 * Based in part on the tar implementation from busybox-0.28
 *  Copyright (C) 1995 Bruce Perens
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
//config:config TAR
//config:	bool "tar (40 kb)"
//config:	default y
//config:	help
//config:	tar is an archiving program. It's commonly used with gzip to
//config:	create compressed archives. It's probably the most widely used
//config:	UNIX archive program.
//config:
//config:config FEATURE_TAR_LONG_OPTIONS
//config:	bool "Enable long options"
//config:	default y
//config:	depends on TAR && LONG_OPTS
//config:
//config:config FEATURE_TAR_CREATE
//config:	bool "Enable -c (archive creation)"
//config:	default y
//config:	depends on TAR
//config:
//config:config FEATURE_TAR_AUTODETECT
//config:	bool "Autodetect compressed tarballs"
//config:	default y
//config:	depends on TAR && (FEATURE_SEAMLESS_Z || FEATURE_SEAMLESS_GZ || FEATURE_SEAMLESS_BZ2 || FEATURE_SEAMLESS_LZMA || FEATURE_SEAMLESS_XZ)
//config:	help
//config:	With this option tar can automatically detect compressed
//config:	tarballs. Currently it works only on files (not pipes etc).
//config:
//config:config FEATURE_TAR_FROM
//config:	bool "Enable -X (exclude from) and -T (include from) options)"
//config:	default y
//config:	depends on TAR
//config:	help
//config:	If you enable this option you'll be able to specify
//config:	a list of files to include or exclude from an archive.
//config:
//config:config FEATURE_TAR_OLDGNU_COMPATIBILITY
//config:	bool "Support old tar header format"
//config:	default y
//config:	depends on TAR || DPKG
//config:	help
//config:	This option is required to unpack archives created in
//config:	the old GNU format; help to kill this old format by
//config:	repacking your ancient archives with the new format.
//config:
//config:config FEATURE_TAR_OLDSUN_COMPATIBILITY
//config:	bool "Enable untarring of tarballs with checksums produced by buggy Sun tar"
//config:	default y
//config:	depends on TAR || DPKG
//config:	help
//config:	This option is required to unpack archives created by some old
//config:	version of Sun's tar (it was calculating checksum using signed
//config:	arithmetic). It is said to be fixed in newer Sun tar, but "old"
//config:	tarballs still exist.
//config:
//config:config FEATURE_TAR_GNU_EXTENSIONS
//config:	bool "Support GNU tar extensions (long filenames)"
//config:	default y
//config:	depends on TAR || DPKG
//config:
//config:config FEATURE_TAR_TO_COMMAND
//config:	bool "Support writing to an external program (--to-command)"
//config:	default y
//config:	depends on TAR && FEATURE_TAR_LONG_OPTIONS
//config:	help
//config:	If you enable this option you'll be able to instruct tar to send
//config:	the contents of each extracted file to the standard input of an
//config:	external program.
//config:
//config:config FEATURE_TAR_UNAME_GNAME
//config:	bool "Enable use of user and group names"
//config:	default y
//config:	depends on TAR
//config:	help
//config:	Enable use of user and group names in tar. This affects contents
//config:	listings (-t) and preserving permissions when unpacking (-p).
//config:	+200 bytes.
//config:
//config:config FEATURE_TAR_NOPRESERVE_TIME
//config:	bool "Enable -m (do not preserve time) GNU option"
//config:	default y
//config:	depends on TAR
//config:
//config:config FEATURE_TAR_SELINUX
//config:	bool "Support extracting SELinux labels"
//config:	default n
//config:	depends on TAR && SELINUX
//config:	help
//config:	With this option busybox supports restoring SELinux labels
//config:	when extracting files from tar archives.

//applet:IF_TAR(APPLET(tar, BB_DIR_BIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_TAR) += tar.o

#include <fnmatch.h>
#include "libbb.h"
#include "common_bufsiz.h"
#include "bb_archive.h"
/* FIXME: Stop using this non-standard feature */
#ifndef FNM_LEADING_DIR
# define FNM_LEADING_DIR 0
#endif

#if 0
# define DBG(fmt, ...) bb_error_msg("%s: " fmt, __func__, ## __VA_ARGS__)
#else
# define DBG(...) ((void)0)
#endif
#define DBG_OPTION_PARSING 0


#define block_buf bb_common_bufsiz1
#define INIT_G() do { setup_common_bufsiz(); } while (0)


#if ENABLE_FEATURE_TAR_CREATE

/*
** writeTarFile(), writeFileToTarball(), and writeTarHeader() are
** the only functions that deal with the HardLinkInfo structure.
** Even these functions use the xxxHardLinkInfo() functions.
*/
typedef struct HardLinkInfo {
	struct HardLinkInfo *next; /* Next entry in list */
	dev_t dev;                 /* Device number */
	ino_t ino;                 /* Inode number */
//	short linkCount;           /* (Hard) Link Count */
	char name[1];              /* Start of filename (must be last) */
} HardLinkInfo;

/* Some info to be carried along when creating a new tarball */
typedef struct TarBallInfo {
	int tarFd;                      /* Open-for-write file descriptor
	                                 * for the tarball */
	int verboseFlag;                /* Whether to print extra stuff or not */
	const llist_t *excludeList;     /* List of files to not include */
	HardLinkInfo *hlInfoHead;       /* Hard Link Tracking Information */
	HardLinkInfo *hlInfo;           /* Hard Link Info for the current file */
//TODO: save only st_dev + st_ino
	struct stat tarFileStatBuf;     /* Stat info for the tarball, letting
	                                 * us know the inode and device that the
	                                 * tarball lives, so we can avoid trying
	                                 * to include the tarball into itself */
} TarBallInfo;

/* A nice enum with all the possible tar file content types */
enum {
	REGTYPE = '0',		/* regular file */
	REGTYPE0 = '\0',	/* regular file (ancient bug compat) */
	LNKTYPE = '1',		/* hard link */
	SYMTYPE = '2',		/* symbolic link */
	CHRTYPE = '3',		/* character special */
	BLKTYPE = '4',		/* block special */
	DIRTYPE = '5',		/* directory */
	FIFOTYPE = '6',		/* FIFO special */
	CONTTYPE = '7',		/* reserved */
	GNULONGLINK = 'K',	/* GNU long (>100 chars) link name */
	GNULONGNAME = 'L',	/* GNU long (>100 chars) file name */
};

/* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
static void addHardLinkInfo(HardLinkInfo **hlInfoHeadPtr,
					struct stat *statbuf,
					const char *fileName)
{
	/* Note: hlInfoHeadPtr can never be NULL! */
	HardLinkInfo *hlInfo;

	hlInfo = xmalloc(sizeof(HardLinkInfo) + strlen(fileName));
	hlInfo->next = *hlInfoHeadPtr;
	*hlInfoHeadPtr = hlInfo;
	hlInfo->dev = statbuf->st_dev;
	hlInfo->ino = statbuf->st_ino;
//	hlInfo->linkCount = statbuf->st_nlink;
	strcpy(hlInfo->name, fileName);
}

static void freeHardLinkInfo(HardLinkInfo **hlInfoHeadPtr)
{
	HardLinkInfo *hlInfo;
	HardLinkInfo *hlInfoNext;

	if (hlInfoHeadPtr) {
		hlInfo = *hlInfoHeadPtr;
		while (hlInfo) {
			hlInfoNext = hlInfo->next;
			free(hlInfo);
			hlInfo = hlInfoNext;
		}
		*hlInfoHeadPtr = NULL;
	}
}

/* Might be faster (and bigger) if the dev/ino were stored in numeric order ;) */
static HardLinkInfo *findHardLinkInfo(HardLinkInfo *hlInfo, struct stat *statbuf)
{
	while (hlInfo) {
		if (statbuf->st_ino == hlInfo->ino
		 && statbuf->st_dev == hlInfo->dev
		) {
			DBG("found hardlink:'%s'", hlInfo->name);
			break;
		}
		hlInfo = hlInfo->next;
	}
	return hlInfo;
}

/* Put an octal string into the specified buffer.
 * The number is zero padded and possibly null terminated.
 * Stores low-order bits only if whole value does not fit. */
static void putOctal(char *cp, int len, off_t value)
{
	char tempBuffer[sizeof(off_t)*3 + 1];
	char *tempString = tempBuffer;
	int width;

	width = sprintf(tempBuffer, "%0*"OFF_FMT"o", len, value);
	tempString += (width - len);

	/* If string has leading zeroes, we can drop one */
	/* and field will have trailing '\0' */
	/* (increases chances of compat with other tars) */
	if (tempString[0] == '0')
		tempString++;

	/* Copy the string to the field */
	memcpy(cp, tempString, len);
}
#define PUT_OCTAL(a, b) putOctal((a), sizeof(a), (b))

static void chksum_and_xwrite(int fd, struct tar_header_t* hp)
{
	/* POSIX says that checksum is done on unsigned bytes
	 * (Sun and HP-UX gets it wrong... more details in
	 * GNU tar source) */
	const unsigned char *cp;
	int chksum, size;

	strcpy(hp->magic, "ustar  ");

	/* Calculate and store the checksum (i.e., the sum of all of the bytes of
	 * the header).  The checksum field must be filled with blanks for the
	 * calculation.  The checksum field is formatted differently from the
	 * other fields: it has 6 digits, a null, then a space -- rather than
	 * digits, followed by a null like the other fields... */
	memset(hp->chksum, ' ', sizeof(hp->chksum));
	cp = (const unsigned char *) hp;
	chksum = 0;
	size = sizeof(*hp);
	do { chksum += *cp++; } while (--size);
	putOctal(hp->chksum, sizeof(hp->chksum)-1, chksum);

	/* Now write the header out to disk */
	xwrite(fd, hp, sizeof(*hp));
}

#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
static void writeLongname(int fd, int type, const char *name, int dir)
{
	static const struct {
		char mode[8];             /* 100-107 */
		char uid[8];              /* 108-115 */
		char gid[8];              /* 116-123 */
		char size[12];            /* 124-135 */
		char mtime[12];           /* 136-147 */
	} prefilled = {
		"0000000",
		"0000000",
		"0000000",
		"00000000000",
		"00000000000",
	};
	struct tar_header_t header;
	int size;

	dir = !!dir; /* normalize: 0/1 */
	size = strlen(name) + 1 + dir; /* GNU tar uses strlen+1 */
	/* + dir: account for possible '/' */

	memset(&header, 0, sizeof(header));
	strcpy(header.name, "././@LongLink");
	memcpy(header.mode, prefilled.mode, sizeof(prefilled));
	PUT_OCTAL(header.size, size);
	header.typeflag = type;
	chksum_and_xwrite(fd, &header);

	/* Write filename[/] and pad the block. */
	/* dir=0: writes 'name<NUL>', pads */
	/* dir=1: writes 'name', writes '/<NUL>', pads */
	dir *= 2;
	xwrite(fd, name, size - dir);
	xwrite(fd, "/", dir);
	size = (-size) & (TAR_BLOCK_SIZE-1);
	memset(&header, 0, size);
	xwrite(fd, &header, size);
}
#endif

/* Write out a tar header for the specified file/directory/whatever */
static int writeTarHeader(struct TarBallInfo *tbInfo,
		const char *header_name, const char *fileName, struct stat *statbuf)
{
	struct tar_header_t header;

	memset(&header, 0, sizeof(header));

	strncpy(header.name, header_name, sizeof(header.name));

	/* POSIX says to mask mode with 07777. */
	PUT_OCTAL(header.mode, statbuf->st_mode & 07777);
	PUT_OCTAL(header.uid, statbuf->st_uid);
	PUT_OCTAL(header.gid, statbuf->st_gid);
	memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */
	/* users report that files with negative st_mtime cause trouble, so: */
	PUT_OCTAL(header.mtime, statbuf->st_mtime >= 0 ? statbuf->st_mtime : 0);

	/* Enter the user and group names */
	safe_strncpy(header.uname, get_cached_username(statbuf->st_uid), sizeof(header.uname));
	safe_strncpy(header.gname, get_cached_groupname(statbuf->st_gid), sizeof(header.gname));

	if (tbInfo->hlInfo) {
		/* This is a hard link */
		header.typeflag = LNKTYPE;
		strncpy(header.linkname, tbInfo->hlInfo->name,
				sizeof(header.linkname));
#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
		/* Write out long linkname if needed */
		if (header.linkname[sizeof(header.linkname)-1])
			writeLongname(tbInfo->tarFd, GNULONGLINK,
					tbInfo->hlInfo->name, 0);
#endif
	} else if (S_ISLNK(statbuf->st_mode)) {
		char *lpath = xmalloc_readlink_or_warn(fileName);
		if (!lpath)
			return FALSE;
		header.typeflag = SYMTYPE;
		strncpy(header.linkname, lpath, sizeof(header.linkname));
#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
		/* Write out long linkname if needed */
		if (header.linkname[sizeof(header.linkname)-1])
			writeLongname(tbInfo->tarFd, GNULONGLINK, lpath, 0);
#else
		/* If it is larger than 100 bytes, bail out */
		if (header.linkname[sizeof(header.linkname)-1]) {
			free(lpath);
			bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
			return FALSE;
		}
#endif
		free(lpath);
	} else if (S_ISDIR(statbuf->st_mode)) {
		header.typeflag = DIRTYPE;
		/* Append '/' only if there is a space for it */
		if (!header.name[sizeof(header.name)-1])
			header.name[strlen(header.name)] = '/';
	} else if (S_ISCHR(statbuf->st_mode)) {
		header.typeflag = CHRTYPE;
		PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
		PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
	} else if (S_ISBLK(statbuf->st_mode)) {
		header.typeflag = BLKTYPE;
		PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
		PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
	} else if (S_ISFIFO(statbuf->st_mode)) {
		header.typeflag = FIFOTYPE;
	} else if (S_ISREG(statbuf->st_mode)) {
		/* header.size field is 12 bytes long */
		/* Does octal-encoded size fit? */
		uoff_t filesize = statbuf->st_size;
		if (sizeof(filesize) <= 4
		 || filesize <= (uoff_t)0777777777777LL
		) {
			PUT_OCTAL(header.size, filesize);
		}
		/* Does base256-encoded size fit?
		 * It always does unless off_t is wider than 64 bits.
		 */
		else if (ENABLE_FEATURE_TAR_GNU_EXTENSIONS
#if ULLONG_MAX > 0xffffffffffffffffLL /* 2^64-1 */
		 && (filesize <= 0x3fffffffffffffffffffffffLL)
#endif
		) {
			/* GNU tar uses "base-256 encoding" for very large numbers.
			 * Encoding is binary, with highest bit always set as a marker
			 * and sign in next-highest bit:
			 * 80 00 .. 00 - zero
			 * bf ff .. ff - largest positive number
			 * ff ff .. ff - minus 1
			 * c0 00 .. 00 - smallest negative number
			 */
			char *p8 = header.size + sizeof(header.size);
			do {
				*--p8 = (uint8_t)filesize;
				filesize >>= 8;
			} while (p8 != header.size);
			*p8 |= 0x80;
		} else {
			bb_error_msg_and_die("can't store file '%s' "
				"of size %"OFF_FMT"u, aborting",
				fileName, statbuf->st_size);
		}
		header.typeflag = REGTYPE;
	} else {
		bb_error_msg("%s: unknown file type", fileName);
		return FALSE;
	}

#if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
	/* Write out long name if needed */
	/* (we, like GNU tar, output long linkname *before* long name) */
	if (header.name[sizeof(header.name)-1])
		writeLongname(tbInfo->tarFd, GNULONGNAME,
				header_name, S_ISDIR(statbuf->st_mode));
#endif

	/* Now write the header out to disk */
	chksum_and_xwrite(tbInfo->tarFd, &header);

	/* Now do the verbose thing (or not) */
	if (tbInfo->verboseFlag) {
		FILE *vbFd = stdout;

		/* If archive goes to stdout, verbose goes to stderr */
		if (tbInfo->tarFd == STDOUT_FILENO)
			vbFd = stderr;
		/* GNU "tar cvvf" prints "extended" listing a-la "ls -l" */
		/* We don't have such excesses here: for us "v" == "vv" */
		/* '/' is probably a GNUism */
		fprintf(vbFd, "%s%s\n", header_name,
				S_ISDIR(statbuf->st_mode) ? "/" : "");
	}

	return TRUE;
}

#if ENABLE_FEATURE_TAR_FROM
static int exclude_file(const llist_t *excluded_files, const char *file)
{
	while (excluded_files) {
		if (excluded_files->data[0] == '/') {
			if (fnmatch(excluded_files->data, file,
					FNM_PATHNAME | FNM_LEADING_DIR) == 0)
				return 1;
		} else {
			const char *p;

			for (p = file; p[0] != '\0'; p++) {
				if ((p == file || p[-1] == '/')
				 && p[0] != '/'
				 && fnmatch(excluded_files->data, p,
						FNM_PATHNAME | FNM_LEADING_DIR) == 0
				) {
					return 1;
				}
			}
		}
		excluded_files = excluded_files->link;
	}

	return 0;
}
#else
# define exclude_file(excluded_files, file) 0
#endif

static int FAST_FUNC writeFileToTarball(const char *fileName, struct stat *statbuf,
			void *userData, int depth UNUSED_PARAM)
{
	struct TarBallInfo *tbInfo = (struct TarBallInfo *) userData;
	const char *header_name;
	int inputFileFd = -1;

	DBG("writeFileToTarball('%s')", fileName);

	/* Strip leading '/' and such (must be before memorizing hardlink's name) */
	header_name = strip_unsafe_prefix(fileName);

	if (header_name[0] == '\0')
		return TRUE;

	/* It is against the rules to archive a socket */
	if (S_ISSOCK(statbuf->st_mode)) {
		bb_error_msg("%s: socket ignored", fileName);
		return TRUE;
	}

	/*
	 * Check to see if we are dealing with a hard link.
	 * If so -
	 * Treat the first occurrence of a given dev/inode as a file while
	 * treating any additional occurrences as hard links.  This is done
	 * by adding the file information to the HardLinkInfo linked list.
	 */
	tbInfo->hlInfo = NULL;
	if (!S_ISDIR(statbuf->st_mode) && statbuf->st_nlink > 1) {
		DBG("'%s': st_nlink > 1", header_name);
		tbInfo->hlInfo = findHardLinkInfo(tbInfo->hlInfoHead, statbuf);
		if (tbInfo->hlInfo == NULL) {
			DBG("'%s': addHardLinkInfo", header_name);
			addHardLinkInfo(&tbInfo->hlInfoHead, statbuf, header_name);
		}
	}

	/* It is a bad idea to store the archive we are in the process of creating,
	 * so check the device and inode to be sure that this particular file isn't
	 * the new tarball */
	if (tbInfo->tarFileStatBuf.st_dev == statbuf->st_dev
	 && tbInfo->tarFileStatBuf.st_ino == statbuf->st_ino
	) {
		bb_error_msg("%s: file is the archive; skipping", fileName);
		return TRUE;
	}

	if (exclude_file(tbInfo->excludeList, header_name))
		return SKIP;

#if !ENABLE_FEATURE_TAR_GNU_EXTENSIONS
	if (strlen(header_name) >= NAME_SIZE) {
		bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
		return TRUE;
	}
#endif

	/* Is this a regular file? */
	if (tbInfo->hlInfo == NULL && S_ISREG(statbuf->st_mode)) {
		/* open the file we want to archive, and make sure all is well */
		inputFileFd = open_or_warn(fileName, O_RDONLY);
		if (inputFileFd < 0) {
			return FALSE;
		}
	}

	/* Add an entry to the tarball */
	if (writeTarHeader(tbInfo, header_name, fileName, statbuf) == FALSE) {
		return FALSE;
	}

	/* If it was a regular file, write out the body */
	if (inputFileFd >= 0) {
		size_t readSize;
		/* Write the file to the archive. */
		/* We record size into header first, */
		/* and then write out file. If file shrinks in between, */
		/* tar will be corrupted. So we don't allow for that. */
		/* NB: GNU tar 1.16 warns and pads with zeroes */
		/* or even seeks back and updates header */
		bb_copyfd_exact_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
		////off_t readSize;
		////readSize = bb_copyfd_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
		////if (readSize != statbuf->st_size && readSize >= 0) {
		////	bb_error_msg_and_die("short read from %s, aborting", fileName);
		////}

		/* Check that file did not grow in between? */
		/* if (safe_read(inputFileFd, 1) == 1) warn but continue? */

		close(inputFileFd);

		/* Pad the file up to the tar block size */
		/* (a few tricks here in the name of code size) */
		readSize = (-(int)statbuf->st_size) & (TAR_BLOCK_SIZE-1);
		memset(block_buf, 0, readSize);
		xwrite(tbInfo->tarFd, block_buf, readSize);
	}

	return TRUE;
}

#if SEAMLESS_COMPRESSION
/* Don't inline: vfork scares gcc and pessimizes code */
static void NOINLINE vfork_compressor(int tar_fd, const char *gzip)
{
	pid_t gzipPid;

	// On Linux, vfork never unpauses parent early, although standard
	// allows for that. Do we want to waste bytes checking for it?
# define WAIT_FOR_CHILD 0
	volatile int vfork_exec_errno = 0;
	struct fd_pair gzipDataPipe;
# if WAIT_FOR_CHILD
	struct fd_pair gzipStatusPipe;
	xpiped_pair(gzipStatusPipe);
# endif
	xpiped_pair(gzipDataPipe);

	signal(SIGPIPE, SIG_IGN); /* we only want EPIPE on errors */

	gzipPid = xvfork();

	if (gzipPid == 0) {
		/* child */
		/* NB: close _first_, then move fds! */
		close(gzipDataPipe.wr);
# if WAIT_FOR_CHILD
		close(gzipStatusPipe.rd);
		/* gzipStatusPipe.wr will close only on exec -
		 * parent waits for this close to happen */
		fcntl(gzipStatusPipe.wr, F_SETFD, FD_CLOEXEC);
# endif
		xmove_fd(gzipDataPipe.rd, 0);
		xmove_fd(tar_fd, 1);
		/* exec gzip/bzip2 program/applet */
		BB_EXECLP(gzip, gzip, "-f", (char *)0);
		vfork_exec_errno = errno;
		_exit(EXIT_FAILURE);
	}

	/* parent */
	xmove_fd(gzipDataPipe.wr, tar_fd);
	close(gzipDataPipe.rd);
# if WAIT_FOR_CHILD
	close(gzipStatusPipe.wr);
	while (1) {
		char buf;
		int n;

		/* Wait until child execs (or fails to) */
		n = full_read(gzipStatusPipe.rd, &buf, 1);
		if (n < 0 /* && errno == EAGAIN */)
			continue;	/* try it again */
	}
	close(gzipStatusPipe.rd);
# endif
	if (vfork_exec_errno) {
		errno = vfork_exec_errno;
		bb_perror_msg_and_die("can't execute '%s'", gzip);
	}
}
#endif /* SEAMLESS_COMPRESSION */


#if !SEAMLESS_COMPRESSION
/* Do not pass gzip flag to writeTarFile() */
#define writeTarFile(tar_fd, verboseFlag, recurseFlags, include, exclude, gzip) \
	writeTarFile(tar_fd, verboseFlag, recurseFlags, include, exclude)
#endif
/* gcc 4.2.1 inlines it, making code bigger */
static NOINLINE int writeTarFile(int tar_fd, int verboseFlag,
	int recurseFlags, const llist_t *include,
	const llist_t *exclude, const char *gzip)
{
	int errorFlag = FALSE;
	struct TarBallInfo tbInfo;

	tbInfo.hlInfoHead = NULL;
	tbInfo.tarFd = tar_fd;
	tbInfo.verboseFlag = verboseFlag;

	/* Store the stat info for the tarball's file, so
	 * can avoid including the tarball into itself....  */
	xfstat(tbInfo.tarFd, &tbInfo.tarFileStatBuf, "can't stat tar file");

#if SEAMLESS_COMPRESSION
	if (gzip)
		vfork_compressor(tbInfo.tarFd, gzip);
#endif

	tbInfo.excludeList = exclude;

	/* Read the directory/files and iterate over them one at a time */
	while (include) {
		if (!recursive_action(include->data, recurseFlags,
				writeFileToTarball, writeFileToTarball, &tbInfo, 0)
		) {
			errorFlag = TRUE;
		}
		include = include->link;
	}
	/* Write two empty blocks to the end of the archive */
	memset(block_buf, 0, 2*TAR_BLOCK_SIZE);
	xwrite(tbInfo.tarFd, block_buf, 2*TAR_BLOCK_SIZE);

	/* To be pedantically correct, we would check if the tarball
	 * is smaller than 20 tar blocks, and pad it if it was smaller,
	 * but that isn't necessary for GNU tar interoperability, and
	 * so is considered a waste of space */

	/* Close so the child process (if any) will exit */
	close(tbInfo.tarFd);

	/* Hang up the tools, close up shop, head home */
	if (ENABLE_FEATURE_CLEAN_UP)
		freeHardLinkInfo(&tbInfo.hlInfoHead);

	if (errorFlag)
		bb_error_msg("error exit delayed from previous errors");

#if SEAMLESS_COMPRESSION
	if (gzip) {
		int status;
		if (safe_waitpid(-1, &status, 0) == -1)
			bb_perror_msg("waitpid");
		else if (!WIFEXITED(status) || WEXITSTATUS(status))
			/* gzip was killed or has exited with nonzero! */
			errorFlag = TRUE;
	}
#endif
	return errorFlag;
}
#else /* !FEATURE_TAR_CREATE */
# define writeTarFile(...) 0
#endif

#if ENABLE_FEATURE_TAR_FROM
static llist_t *append_file_list_to_list(llist_t *list)
{
	FILE *src_stream;
	char *line;
	llist_t *newlist = NULL;

	while (list) {
		src_stream = xfopen_stdin(llist_pop(&list));
		while ((line = xmalloc_fgetline(src_stream)) != NULL) {
			/* kill trailing '/' unless the string is just "/" */
			char *cp = last_char_is(line, '/');
			if (cp > line)
				*cp = '\0';
			llist_add_to_end(&newlist, line);
		}
		fclose(src_stream);
	}
	return newlist;
}
#endif

//usage:#define tar_trivial_usage
//usage:	"-[" IF_FEATURE_TAR_CREATE("c") "xt"
//usage:	IF_FEATURE_SEAMLESS_Z("Z")
//usage:	IF_FEATURE_SEAMLESS_GZ("z")
//usage:	IF_FEATURE_SEAMLESS_XZ("J")
//usage:	IF_FEATURE_SEAMLESS_BZ2("j")
//usage:	IF_FEATURE_SEAMLESS_LZMA("a")
//usage:	IF_FEATURE_TAR_CREATE("h")
//usage:	IF_FEATURE_TAR_NOPRESERVE_TIME("m")
//usage:	"vO] "
//usage:	IF_FEATURE_TAR_FROM("[-X FILE] [-T FILE] ")
//usage:	"[-f TARFILE] [-C DIR] [FILE]..."
//usage:#define tar_full_usage "\n\n"
//usage:	IF_FEATURE_TAR_CREATE("Create, extract, ")
//usage:	IF_NOT_FEATURE_TAR_CREATE("Extract ")
//usage:	"or list files from a tar file\n"
//usage:     "\nOperation:"
//usage:	IF_FEATURE_TAR_CREATE(
//usage:     "\n	c	Create"
//usage:	)
//usage:     "\n	x	Extract"
//usage:     "\n	t	List"
//usage:     "\n	f	Name of TARFILE ('-' for stdin/out)"
//usage:     "\n	C	Change to DIR before operation"
//usage:     "\n	v	Verbose"
//usage:	IF_FEATURE_SEAMLESS_Z(
//usage:     "\n	Z	(De)compress using compress"
//usage:	)
//usage:	IF_FEATURE_SEAMLESS_GZ(
//usage:     "\n	z	(De)compress using gzip"
//usage:	)
//usage:	IF_FEATURE_SEAMLESS_XZ(
//usage:     "\n	J	(De)compress using xz"
//usage:	)
//usage:	IF_FEATURE_SEAMLESS_BZ2(
//usage:     "\n	j	(De)compress using bzip2"
//usage:	)
//usage:	IF_FEATURE_SEAMLESS_LZMA(
//usage:     "\n	a	(De)compress using lzma"
//usage:	)
//usage:     "\n	O	Extract to stdout"
//usage:	IF_FEATURE_TAR_CREATE(
//usage:     "\n	h	Follow symlinks"
//usage:	)
//usage:	IF_FEATURE_TAR_NOPRESERVE_TIME(
//usage:     "\n	m	Don't restore mtime"
//usage:	)
//usage:	IF_FEATURE_TAR_FROM(
//usage:	IF_FEATURE_TAR_LONG_OPTIONS(
//usage:     "\n	exclude	File to exclude"
//usage:	)
//usage:     "\n	X	File with names to exclude"
//usage:     "\n	T	File with names to include"
//usage:	)
//usage:
//usage:#define tar_example_usage
//usage:       "$ zcat /tmp/tarball.tar.gz | tar -xf -\n"
//usage:       "$ tar -cf /tmp/tarball.tar /usr/local\n"

// Supported but aren't in --help:
//	o	no-same-owner
//	p	same-permissions
//	k	keep-old
//	no-recursion
//	numeric-owner
//	no-same-permissions
//	overwrite
//IF_FEATURE_TAR_TO_COMMAND(
//	to-command
//)

enum {
	OPTBIT_KEEP_OLD = 8,
	IF_FEATURE_TAR_CREATE(   OPTBIT_CREATE      ,)
	IF_FEATURE_TAR_CREATE(   OPTBIT_DEREFERENCE ,)
	IF_FEATURE_SEAMLESS_BZ2( OPTBIT_BZIP2       ,)
	IF_FEATURE_SEAMLESS_LZMA(OPTBIT_LZMA        ,)
	IF_FEATURE_TAR_FROM(     OPTBIT_INCLUDE_FROM,)
	IF_FEATURE_TAR_FROM(     OPTBIT_EXCLUDE_FROM,)
	IF_FEATURE_SEAMLESS_GZ(  OPTBIT_GZIP        ,)
	IF_FEATURE_SEAMLESS_XZ(  OPTBIT_XZ          ,) // 16th bit
	IF_FEATURE_SEAMLESS_Z(   OPTBIT_COMPRESS    ,)
	IF_FEATURE_TAR_NOPRESERVE_TIME(OPTBIT_NOPRESERVE_TIME,)
#if ENABLE_FEATURE_TAR_LONG_OPTIONS
	OPTBIT_STRIP_COMPONENTS,
	OPTBIT_NORECURSION,
	IF_FEATURE_TAR_TO_COMMAND(OPTBIT_2COMMAND   ,)
	OPTBIT_NUMERIC_OWNER,
	OPTBIT_NOPRESERVE_PERM,
	OPTBIT_OVERWRITE,
#endif
	OPT_TEST         = 1 << 0, // t
	OPT_EXTRACT      = 1 << 1, // x
	OPT_BASEDIR      = 1 << 2, // C
	OPT_TARNAME      = 1 << 3, // f
	OPT_2STDOUT      = 1 << 4, // O
	OPT_NOPRESERVE_OWNER = 1 << 5, // o == no-same-owner
	OPT_P            = 1 << 6, // p
	OPT_VERBOSE      = 1 << 7, // v
	OPT_KEEP_OLD     = 1 << 8, // k
	OPT_CREATE       = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_CREATE      )) + 0, // c
	OPT_DEREFERENCE  = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_DEREFERENCE )) + 0, // h
	OPT_BZIP2        = IF_FEATURE_SEAMLESS_BZ2( (1 << OPTBIT_BZIP2       )) + 0, // j
	OPT_LZMA         = IF_FEATURE_SEAMLESS_LZMA((1 << OPTBIT_LZMA        )) + 0, // a
	OPT_INCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_INCLUDE_FROM)) + 0, // T
	OPT_EXCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_EXCLUDE_FROM)) + 0, // X
	OPT_GZIP         = IF_FEATURE_SEAMLESS_GZ(  (1 << OPTBIT_GZIP        )) + 0, // z
	OPT_XZ           = IF_FEATURE_SEAMLESS_XZ(  (1 << OPTBIT_XZ          )) + 0, // J
	OPT_COMPRESS     = IF_FEATURE_SEAMLESS_Z(   (1 << OPTBIT_COMPRESS    )) + 0, // Z
	OPT_NOPRESERVE_TIME  = IF_FEATURE_TAR_NOPRESERVE_TIME((1 << OPTBIT_NOPRESERVE_TIME)) + 0, // m
	OPT_STRIP_COMPONENTS = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_STRIP_COMPONENTS)) + 0, // strip-components
	OPT_NORECURSION      = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NORECURSION    )) + 0, // no-recursion
	OPT_2COMMAND         = IF_FEATURE_TAR_TO_COMMAND(  (1 << OPTBIT_2COMMAND       )) + 0, // to-command
	OPT_NUMERIC_OWNER    = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NUMERIC_OWNER  )) + 0, // numeric-owner
	OPT_NOPRESERVE_PERM  = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NOPRESERVE_PERM)) + 0, // no-same-permissions
	OPT_OVERWRITE        = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_OVERWRITE      )) + 0, // overwrite

	OPT_ANY_COMPRESS = (OPT_BZIP2 | OPT_LZMA | OPT_GZIP | OPT_XZ | OPT_COMPRESS),
};
#if ENABLE_FEATURE_TAR_LONG_OPTIONS
static const char tar_longopts[] ALIGN1 =
	"list\0"                No_argument       "t"
	"extract\0"             No_argument       "x"
	"directory\0"           Required_argument "C"
	"file\0"                Required_argument "f"
	"to-stdout\0"           No_argument       "O"
	/* do not restore owner */
	/* Note: GNU tar handles 'o' as no-same-owner only on extract,
	 * on create, 'o' is --old-archive. We do not support --old-archive. */
	"no-same-owner\0"       No_argument       "o"
	"same-permissions\0"    No_argument       "p"
	"verbose\0"             No_argument       "v"
	"keep-old\0"            No_argument       "k"
# if ENABLE_FEATURE_TAR_CREATE
	"create\0"              No_argument       "c"
	"dereference\0"         No_argument       "h"
# endif
# if ENABLE_FEATURE_SEAMLESS_BZ2
	"bzip2\0"               No_argument       "j"
# endif
# if ENABLE_FEATURE_SEAMLESS_LZMA
	"lzma\0"                No_argument       "a"
# endif
# if ENABLE_FEATURE_TAR_FROM
	"files-from\0"          Required_argument "T"
	"exclude-from\0"        Required_argument "X"
# endif
# if ENABLE_FEATURE_SEAMLESS_GZ
	"gzip\0"                No_argument       "z"
# endif
# if ENABLE_FEATURE_SEAMLESS_XZ
	"xz\0"                  No_argument       "J"
# endif
# if ENABLE_FEATURE_SEAMLESS_Z
	"compress\0"            No_argument       "Z"
# endif
# if ENABLE_FEATURE_TAR_NOPRESERVE_TIME
	"touch\0"               No_argument       "m"
# endif
	"strip-components\0"	Required_argument "\xf9"
	"no-recursion\0"	No_argument       "\xfa"
# if ENABLE_FEATURE_TAR_TO_COMMAND
	"to-command\0"		Required_argument "\xfb"
# endif
	/* use numeric uid/gid from tar header, not textual */
	"numeric-owner\0"       No_argument       "\xfc"
	/* do not restore mode */
	"no-same-permissions\0" No_argument       "\xfd"
	/* on unpack, open with O_TRUNC and !O_EXCL */
	"overwrite\0"           No_argument       "\xfe"
	/* --exclude takes next bit position in option mask, */
	/* therefore we have to put it _after_ --no-same-permissions */
# if ENABLE_FEATURE_TAR_FROM
	"exclude\0"             Required_argument "\xff"
# endif
	;
# define GETOPT32 getopt32long
# define LONGOPTS ,tar_longopts
#else
# define GETOPT32 getopt32
# define LONGOPTS
#endif

int tar_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int tar_main(int argc UNUSED_PARAM, char **argv)
{
	archive_handle_t *tar_handle;
	char *base_dir = NULL;
	const char *tar_filename = "-";
	unsigned opt;
	int verboseFlag = 0;
#if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
	llist_t *excludes = NULL;
#endif
	INIT_G();

	/* Initialise default values */
	tar_handle = init_handle();
	tar_handle->ah_flags = ARCHIVE_CREATE_LEADING_DIRS
	                     | ARCHIVE_RESTORE_DATE
	                     | ARCHIVE_UNLINK_OLD;

	/* Apparently only root's tar preserves perms (see bug 3844) */
	if (getuid() != 0)
		tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;

#if ENABLE_DESKTOP
	/* Lie to buildroot when it starts asking stupid questions. */
	if (argv[1] && strcmp(argv[1], "--version") == 0) {
		// Output of 'tar --version' examples:
		// tar (GNU tar) 1.15.1
		// tar (GNU tar) 1.25
		// bsdtar 2.8.3 - libarchive 2.8.3
		puts("tar (busybox) " BB_VER);
		return 0;
	}
	if (argv[1] && argv[1][0] != '-') {
		/* Compat:
		 * 1st argument without dash handles options with parameters
		 * differently from dashed one: it takes *next argv[i]*
		 * as paramenter even if there are more chars in 1st argument:
		 *  "tar fx TARFILE" - "x" is not taken as f's param
		 *  but is interpreted as -x option
		 *  "tar -xf TARFILE" - dashed equivalent of the above
		 *  "tar -fx ..." - "x" is taken as f's param
		 * getopt32 wouldn't handle 1st command correctly.
		 * Unfortunately, people do use such commands.
		 * We massage argv[1] to work around it by moving 'f'
		 * to the end of the string.
		 * More contrived "tar fCx TARFILE DIR" still fails,
		 * but such commands are much less likely to be used.
		 */
		char *f = strchr(argv[1], 'f');
		if (f) {
			while (f[1] != '\0') {
				*f = f[1];
				f++;
			}
			*f = 'f';
		}
	}
#endif
	/* Prepend '-' to the first argument if required */
	if (argv[1] && argv[1][0] != '-' && argv[1][0] != '\0')
		argv[1] = xasprintf("-%s", argv[1]);
	opt = GETOPT32(argv, "^"
		"txC:f:Oopvk"
		IF_FEATURE_TAR_CREATE(   "ch"    )
		IF_FEATURE_SEAMLESS_BZ2( "j"     )
		IF_FEATURE_SEAMLESS_LZMA("a"     )
		IF_FEATURE_TAR_FROM(     "T:*X:*")
		IF_FEATURE_SEAMLESS_GZ(  "z"     )
		IF_FEATURE_SEAMLESS_XZ(  "J"     )
		IF_FEATURE_SEAMLESS_Z(   "Z"     )
		IF_FEATURE_TAR_NOPRESERVE_TIME("m")
		IF_FEATURE_TAR_LONG_OPTIONS("\xf9:") // --strip-components
		"\0"
		"tt:vv:" // count -t,-v
#if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
		"\xff::" // --exclude=PATTERN is a list
#endif
		IF_FEATURE_TAR_CREATE("c:") "t:x:" // at least one of these is reqd
		IF_FEATURE_TAR_CREATE("c--tx:t--cx:x--ct") // mutually exclusive
		IF_NOT_FEATURE_TAR_CREATE("t--x:x--t") // mutually exclusive
#if ENABLE_FEATURE_TAR_LONG_OPTIONS
		":\xf9+" // --strip-components=NUM
#endif
		LONGOPTS
		, &base_dir // -C dir
		, &tar_filename // -f filename
		IF_FEATURE_TAR_FROM(, &(tar_handle->accept)) // T
		IF_FEATURE_TAR_FROM(, &(tar_handle->reject)) // X
#if ENABLE_FEATURE_TAR_LONG_OPTIONS
		, &tar_handle->tar__strip_components // --strip-components
#endif
		IF_FEATURE_TAR_TO_COMMAND(, &(tar_handle->tar__to_command)) // --to-command
#if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
		, &excludes // --exclude
#endif
		, &verboseFlag // combined count for -t and -v
		, &verboseFlag // combined count for -t and -v
		);
#if DBG_OPTION_PARSING
	bb_error_msg("opt: 0x%08x", opt);
# define showopt(o) bb_error_msg("opt & %s(%x): %x", #o, o, opt & o);
	showopt(OPT_TEST            );
	showopt(OPT_EXTRACT         );
	showopt(OPT_BASEDIR         );
	showopt(OPT_TARNAME         );
	showopt(OPT_2STDOUT         );
	showopt(OPT_NOPRESERVE_OWNER);
	showopt(OPT_P               );
	showopt(OPT_VERBOSE         );
	showopt(OPT_KEEP_OLD        );
	showopt(OPT_CREATE          );
	showopt(OPT_DEREFERENCE     );
	showopt(OPT_BZIP2           );
	showopt(OPT_LZMA            );
	showopt(OPT_INCLUDE_FROM    );
	showopt(OPT_EXCLUDE_FROM    );
	showopt(OPT_GZIP            );
	showopt(OPT_XZ              );
	showopt(OPT_COMPRESS        );
	showopt(OPT_NOPRESERVE_TIME );
	showopt(OPT_STRIP_COMPONENTS);
	showopt(OPT_NORECURSION     );
	showopt(OPT_2COMMAND        );
	showopt(OPT_NUMERIC_OWNER   );
	showopt(OPT_NOPRESERVE_PERM );
	showopt(OPT_OVERWRITE       );
	showopt(OPT_ANY_COMPRESS    );
	bb_error_msg("base_dir:'%s'", base_dir);
	bb_error_msg("tar_filename:'%s'", tar_filename);
	bb_error_msg("verboseFlag:%d", verboseFlag);
	bb_error_msg("tar_handle->tar__to_command:'%s'", tar_handle->tar__to_command);
	bb_error_msg("tar_handle->tar__strip_components:%u", tar_handle->tar__strip_components);
	return 0;
# undef showopt
#endif
	argv += optind;

	if (verboseFlag)
		tar_handle->action_header = header_verbose_list;
	if (verboseFlag == 1)
		tar_handle->action_header = header_list;

	if (opt & OPT_EXTRACT)
		tar_handle->action_data = data_extract_all;

	if (opt & OPT_2STDOUT)
		tar_handle->action_data = data_extract_to_stdout;

	if (opt & OPT_2COMMAND) {
		putenv((char*)"TAR_FILETYPE=f");
		signal(SIGPIPE, SIG_IGN);
		tar_handle->action_data = data_extract_to_command;
		IF_FEATURE_TAR_TO_COMMAND(tar_handle->tar__to_command_shell = xstrdup(get_shell_name());)
	}

	if (opt & OPT_KEEP_OLD)
		tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;

	if (opt & OPT_NUMERIC_OWNER)
		tar_handle->ah_flags |= ARCHIVE_NUMERIC_OWNER;

	if (opt & OPT_NOPRESERVE_OWNER)
		tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_OWNER;

	if (opt & OPT_NOPRESERVE_PERM)
		tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;

	if (opt & OPT_OVERWRITE) {
		tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;
		tar_handle->ah_flags |= ARCHIVE_O_TRUNC;
	}

	if (opt & OPT_NOPRESERVE_TIME)
		tar_handle->ah_flags &= ~ARCHIVE_RESTORE_DATE;

#if ENABLE_FEATURE_TAR_FROM
	tar_handle->reject = append_file_list_to_list(tar_handle->reject);
# if ENABLE_FEATURE_TAR_LONG_OPTIONS
	/* Append excludes to reject */
	while (excludes) {
		llist_t *next = excludes->link;
		excludes->link = tar_handle->reject;
		tar_handle->reject = excludes;
		excludes = next;
	}
# endif
	tar_handle->accept = append_file_list_to_list(tar_handle->accept);
#endif

	/* Setup an array of filenames to work with */
	/* TODO: This is the same as in ar, make a separate function? */
	while (*argv) {
		/* kill trailing '/' unless the string is just "/" */
		char *cp = last_char_is(*argv, '/');
		if (cp > *argv)
			*cp = '\0';
		llist_add_to_end(&tar_handle->accept, *argv);
		argv++;
	}

	if (tar_handle->accept || tar_handle->reject)
		tar_handle->filter = filter_accept_reject_list;

	/* Open the tar file */
	{
		int tar_fd = STDIN_FILENO;
		int flags = O_RDONLY;

		if (opt & OPT_CREATE) {
			/* Make sure there is at least one file to tar up */
			if (tar_handle->accept == NULL)
				bb_error_msg_and_die("empty archive");

			tar_fd = STDOUT_FILENO;
			/* Mimicking GNU tar 1.15.1: */
			flags = O_WRONLY | O_CREAT | O_TRUNC;
		}

		if (LONE_DASH(tar_filename)) {
			tar_handle->src_fd = tar_fd;
			tar_handle->seek = seek_by_read;
		} else {
			if (ENABLE_FEATURE_TAR_AUTODETECT
			 && flags == O_RDONLY
			 && !(opt & OPT_ANY_COMPRESS)
			) {
				tar_handle->src_fd = open_zipped(tar_filename, /*fail_if_not_compressed:*/ 0);
				if (tar_handle->src_fd < 0)
					bb_perror_msg_and_die("can't open '%s'", tar_filename);
			} else {
				tar_handle->src_fd = xopen(tar_filename, flags);
			}
		}
	}

	if (base_dir)
		xchdir(base_dir);

	//if (SEAMLESS_COMPRESSION)
	//	/* We need to know whether child (gzip/bzip/etc) exits abnormally */
	//	signal(SIGCHLD, check_errors_in_children);

#if ENABLE_FEATURE_TAR_CREATE
	/* Create an archive */
	if (opt & OPT_CREATE) {
# if SEAMLESS_COMPRESSION
		const char *zipMode = NULL;
		if (opt & OPT_COMPRESS)
			zipMode = "compress";
		if (opt & OPT_GZIP)
			zipMode = "gzip";
		if (opt & OPT_BZIP2)
			zipMode = "bzip2";
		if (opt & OPT_LZMA)
			zipMode = "lzma";
		if (opt & OPT_XZ)
			zipMode = "xz";
# endif
		/* NB: writeTarFile() closes tar_handle->src_fd */
		return writeTarFile(tar_handle->src_fd, verboseFlag,
				(opt & OPT_DEREFERENCE ? ACTION_FOLLOWLINKS : 0)
				| (opt & OPT_NORECURSION ? 0 : ACTION_RECURSE),
				tar_handle->accept,
				tar_handle->reject, zipMode);
	}
#endif

	if (opt & OPT_ANY_COMPRESS) {
		USE_FOR_MMU(IF_DESKTOP(long long) int FAST_FUNC (*xformer)(transformer_state_t *xstate);)
		USE_FOR_NOMMU(const char *xformer_prog;)

		if (opt & OPT_COMPRESS) {
			USE_FOR_MMU(IF_FEATURE_SEAMLESS_Z(xformer = unpack_Z_stream;))
			USE_FOR_NOMMU(xformer_prog = "uncompress";)
		}
		if (opt & OPT_GZIP) {
			USE_FOR_MMU(IF_FEATURE_SEAMLESS_GZ(xformer = unpack_gz_stream;))
			USE_FOR_NOMMU(xformer_prog = "gunzip";)
		}
		if (opt & OPT_BZIP2) {
			USE_FOR_MMU(IF_FEATURE_SEAMLESS_BZ2(xformer = unpack_bz2_stream;))
			USE_FOR_NOMMU(xformer_prog = "bunzip2";)
		}
		if (opt & OPT_LZMA) {
			USE_FOR_MMU(IF_FEATURE_SEAMLESS_LZMA(xformer = unpack_lzma_stream;))
			USE_FOR_NOMMU(xformer_prog = "unlzma";)
		}
		if (opt & OPT_XZ) {
			USE_FOR_MMU(IF_FEATURE_SEAMLESS_XZ(xformer = unpack_xz_stream;))
			USE_FOR_NOMMU(xformer_prog = "unxz";)
		}

		fork_transformer_with_sig(tar_handle->src_fd, xformer, xformer_prog);
		/* Can't lseek over pipes */
		tar_handle->seek = seek_by_read;
		/*tar_handle->offset = 0; - already is */
	}

	/* Zero processed headers (== empty file) is not a valid tarball.
	 * We (ab)use bb_got_signal as exitcode here,
	 * because check_errors_in_children() uses _it_ as error indicator.
	 */
	bb_got_signal = EXIT_FAILURE;

	while (get_header_tar(tar_handle) == EXIT_SUCCESS)
		bb_got_signal = EXIT_SUCCESS; /* saw at least one header, good */

	/* Check that every file that should have been extracted was */
	while (tar_handle->accept) {
		if (!find_list_entry(tar_handle->reject, tar_handle->accept->data)
		 && !find_list_entry(tar_handle->passed, tar_handle->accept->data)
		) {
			bb_error_msg_and_die("%s: not found in archive",
				tar_handle->accept->data);
		}
		tar_handle->accept = tar_handle->accept->link;
	}
	if (ENABLE_FEATURE_CLEAN_UP /* && tar_handle->src_fd != STDIN_FILENO */)
		close(tar_handle->src_fd);

	if (SEAMLESS_COMPRESSION || OPT_COMPRESS) {
		/* Set bb_got_signal to 1 if a child died with !0 exitcode */
		check_errors_in_children(0);
	}

	return bb_got_signal;
}