summaryrefslogtreecommitdiff
path: root/archival/lzop.c
blob: 5f2744d91a330041f8c0eba751d0f64ebaa79c7a (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
/*
   This file is part of the lzop file compressor.

   Copyright (C) 1996..2003 Markus Franz Xaver Johannes Oberhumer
   All Rights Reserved.

   Markus F.X.J. Oberhumer <markus@oberhumer.com>
   http://www.oberhumer.com/opensource/lzop/

   lzop and the LZO library are free software; you can redistribute them
   and/or modify them under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of
   the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

   "Minimalized" for busybox by Alain Knaff
*/

#include "libbb.h"
#include "unarchive.h"
#include "liblzo_interface.h"

/* lzo-2.03/src/lzo_ptr.h */
#define pd(a,b)	 ((unsigned)((a)-(b)))

#define lzo_version()			LZO_VERSION
#define lzo_sizeof_dict_t		(sizeof(uint8_t*))

/* lzo-2.03/include/lzo/lzo1x.h */
#define LZO1X_1_MEM_COMPRESS	(16384 * lzo_sizeof_dict_t)
#define LZO1X_1_15_MEM_COMPRESS (32768 * lzo_sizeof_dict_t)
#define LZO1X_999_MEM_COMPRESS	(14 * 16384 * sizeof(short))

/* lzo-2.03/src/lzo1x_oo.c */
#define NO_LIT UINT_MAX

/**********************************************************************/
static void copy2(uint8_t* ip, const uint8_t* m_pos, unsigned off)
{
	ip[0] = m_pos[0];
	if (off == 1)
		ip[1] = m_pos[0];
	else
		ip[1] = m_pos[1];
}

static void copy3(uint8_t* ip, const uint8_t* m_pos, unsigned off)
{
	ip[0] = m_pos[0];
	if (off == 1) {
		ip[2] = ip[1] = m_pos[0];
	}
	else if (off == 2) {
		ip[1] = m_pos[1];
		ip[2] = m_pos[0];
	}
	else {
		ip[1] = m_pos[1];
		ip[2] = m_pos[2];
	}
}

/**********************************************************************/
// optimize a block of data.
/**********************************************************************/
#define TEST_IP		(ip < ip_end)
#define TEST_OP		(op <= op_end)

static NOINLINE int lzo1x_optimize(uint8_t *in, unsigned in_len,
		uint8_t *out, unsigned *out_len,
		void* wrkmem UNUSED_PARAM)
{
	uint8_t* op;
	uint8_t* ip;
	unsigned t;
	uint8_t* m_pos;
	uint8_t* const ip_end = in + in_len;
	uint8_t* const op_end = out + *out_len;
	uint8_t* litp = NULL;
	unsigned lit = 0;
	unsigned next_lit = NO_LIT;
	unsigned nl;
	unsigned long o_m1_a = 0, o_m1_b = 0, o_m2 = 0, o_m3_a = 0, o_m3_b = 0;

//	  LZO_UNUSED(wrkmem);

	*out_len = 0;

	op = out;
	ip = in;

	if (*ip > 17) {
		t = *ip++ - 17;
		if (t < 4)
			goto match_next;
		goto first_literal_run;
	}

	while (TEST_IP && TEST_OP) {
		t = *ip++;
		if (t >= 16)
			goto match;
		/* a literal run */
		litp = ip - 1;
		if (t == 0) {
			t = 15;
			while (*ip == 0)
				t += 255, ip++;
			t += *ip++;
		}
		lit = t + 3;
		/* copy literals */
 copy_literal_run:
		*op++ = *ip++;
		*op++ = *ip++;
		*op++ = *ip++;
 first_literal_run:
		do *op++ = *ip++; while (--t > 0);

		t = *ip++;

		if (t >= 16)
			goto match;
#if defined(LZO1X)
		m_pos = op - 1 - 0x800;
#elif defined(LZO1Y)
		m_pos = op - 1 - 0x400;
#endif
		m_pos -= t >> 2;
		m_pos -= *ip++ << 2;
		*op++ = *m_pos++;
		*op++ = *m_pos++;
		*op++ = *m_pos++;
		lit = 0;
		goto match_done;


		/* handle matches */
		do {
			if (t < 16) { /* a M1 match */
				m_pos = op - 1;
				m_pos -= t >> 2;
				m_pos -= *ip++ << 2;

				if (litp == NULL)
					goto copy_m1;

				nl = ip[-2] & 3;
				/* test if a match follows */
				if (nl == 0 && lit == 1 && ip[0] >= 16) {
					next_lit = nl;
					/* adjust length of previous short run */
					lit += 2;
					*litp = (unsigned char)((*litp & ~3) | lit);
					/* copy over the 2 literals that replace the match */
					copy2(ip-2, m_pos, pd(op, m_pos));
					o_m1_a++;
				}
				/* test if a literal run follows */
				else if (nl == 0 && ip[0] < 16 && ip[0] != 0 &&
						 (lit + 2 + ip[0] < 16))
				{
					t = *ip++;
					/* remove short run */
					*litp &= ~3;
					/* copy over the 2 literals that replace the match */
					copy2(ip-3+1,m_pos,pd(op,m_pos));
					/* move literals 1 byte ahead */
					litp += 2;
					if (lit > 0)
						memmove(litp+1, litp, lit);
					/* insert new length of long literal run */
					lit += 2 + t + 3;
					*litp = (unsigned char)(lit - 3);

					o_m1_b++;
					*op++ = *m_pos++; *op++ = *m_pos++;
					goto copy_literal_run;
				}
 copy_m1:
				*op++ = *m_pos++;
				*op++ = *m_pos++;
			} else {
 match:
				if (t >= 64) {				/* a M2 match */
					m_pos = op - 1;
#if defined(LZO1X)
					m_pos -= (t >> 2) & 7;
					m_pos -= *ip++ << 3;
					t = (t >> 5) - 1;
#elif defined(LZO1Y)
					m_pos -= (t >> 2) & 3;
					m_pos -= *ip++ << 2;
					t = (t >> 4) - 3;
#endif
					if (litp == NULL)
						goto copy_m;

					nl = ip[-2] & 3;
					/* test if in beetween two long literal runs */
					if (t == 1 && lit > 3 && nl == 0
					 && ip[0] < 16 && ip[0] != 0 && (lit + 3 + ip[0] < 16)
					) {
						t = *ip++;
						/* copy over the 3 literals that replace the match */
						copy3(ip-1-2,m_pos,pd(op,m_pos));
						/* set new length of previous literal run */
						lit += 3 + t + 3;
						*litp = (unsigned char)(lit - 3);
						o_m2++;
						*op++ = *m_pos++;
						*op++ = *m_pos++;
						*op++ = *m_pos++;
						goto copy_literal_run;
					}
				} else {
					if (t >= 32) {			/* a M3 match */
						t &= 31;
						if (t == 0) {
							t = 31;
							while (*ip == 0)
								t += 255, ip++;
							t += *ip++;
						}
						m_pos = op - 1;
						m_pos -= *ip++ >> 2;
						m_pos -= *ip++ << 6;
					} else {					/* a M4 match */
						m_pos = op;
						m_pos -= (t & 8) << 11;
						t &= 7;
						if (t == 0) {
							t = 7;
							while (*ip == 0)
								t += 255, ip++;
							t += *ip++;
						}
						m_pos -= *ip++ >> 2;
						m_pos -= *ip++ << 6;
						if (m_pos == op)
							goto eof_found;
						m_pos -= 0x4000;
					}
					if (litp == NULL)
						goto copy_m;

					nl = ip[-2] & 3;
					/* test if in beetween two matches */
					if (t == 1 && lit == 0 && nl == 0 && ip[0] >= 16) {
						next_lit = nl;
						/* make a previous short run */
						lit += 3;
						*litp = (unsigned char)((*litp & ~3) | lit);
						/* copy over the 3 literals that replace the match */
						copy3(ip-3,m_pos,pd(op,m_pos));
						o_m3_a++;
					}
					/* test if a literal run follows */
					else if (t == 1 && lit <= 3 && nl == 0
					 && ip[0] < 16 && ip[0] != 0 && (lit + 3 + ip[0] < 16)
					) {
						t = *ip++;
						/* remove short run */
						*litp &= ~3;
						/* copy over the 3 literals that replace the match */
						copy3(ip-4+1,m_pos,pd(op,m_pos));
						/* move literals 1 byte ahead */
						litp += 2;
						if (lit > 0)
							memmove(litp+1,litp,lit);
						/* insert new length of long literal run */
						lit += 3 + t + 3;
						*litp = (unsigned char)(lit - 3);

						o_m3_b++;
						*op++ = *m_pos++;
						*op++ = *m_pos++;
						*op++ = *m_pos++;
						goto copy_literal_run;
					}
				}
 copy_m:
				*op++ = *m_pos++;
				*op++ = *m_pos++;
				do *op++ = *m_pos++; while (--t > 0);
			}

 match_done:
			if (next_lit == NO_LIT) {
				t = ip[-2] & 3;
				lit = t;
				litp = ip - 2;
			}
			else
				t = next_lit;
			next_lit = NO_LIT;
			if (t == 0)
				break;
			/* copy literals */
 match_next:
			do *op++ = *ip++; while (--t > 0);
			t = *ip++;
		} while (TEST_IP && TEST_OP);
	}

	/* no EOF code was found */
	*out_len = pd(op, out);
	return LZO_E_EOF_NOT_FOUND;

 eof_found:
//	  LZO_UNUSED(o_m1_a); LZO_UNUSED(o_m1_b); LZO_UNUSED(o_m2);
//	  LZO_UNUSED(o_m3_a); LZO_UNUSED(o_m3_b);
	*out_len = pd(op, out);
	return (ip == ip_end ? LZO_E_OK :
		   (ip < ip_end	 ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
}

/**********************************************************************/
#define F_OS F_OS_UNIX
#define F_CS F_CS_NATIVE

/**********************************************************************/
#define ADLER32_INIT_VALUE 1
#define CRC32_INIT_VALUE   0

/**********************************************************************/
enum {
	M_LZO1X_1    = 1,
	M_LZO1X_1_15 = 2,
	M_LZO1X_999  = 3,
};

/**********************************************************************/
/* header flags */
#define F_ADLER32_D     0x00000001L
#define F_ADLER32_C     0x00000002L
#define F_H_EXTRA_FIELD 0x00000040L
#define F_H_GMTDIFF     0x00000080L
#define F_CRC32_D       0x00000100L
#define F_CRC32_C       0x00000200L
#define F_H_FILTER      0x00000800L
#define F_H_CRC32       0x00001000L
#define F_MASK          0x00003FFFL

/* operating system & file system that created the file [mostly unused] */
#define F_OS_UNIX       0x03000000L
#define F_OS_SHIFT      24
#define F_OS_MASK       0xff000000L

/* character set for file name encoding [mostly unused] */
#define F_CS_NATIVE     0x00000000L
#define F_CS_SHIFT      20
#define F_CS_MASK       0x00f00000L

/* these bits must be zero */
#define F_RESERVED      ((F_MASK | F_OS_MASK | F_CS_MASK) ^ 0xffffffffL)

typedef struct chksum_t {
	uint32_t f_adler32;
	uint32_t f_crc32;
} chksum_t;

typedef struct header_t {
	unsigned version;
	unsigned lib_version;
	unsigned version_needed_to_extract;
	uint32_t flags;
	uint32_t mode;
	uint32_t mtime;
	uint32_t gmtdiff;
	uint32_t header_checksum;

	uint32_t extra_field_len;
	uint32_t extra_field_checksum;

	unsigned char method;
	unsigned char level;

	/* info */
	char name[255+1];
} header_t;

struct globals {
	const uint32_t *lzo_crc32_table;
	chksum_t chksum_in;
	chksum_t chksum_out;
};
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)
//#define G (*ptr_to_globals)
//#define INIT_G() do {
//        SET_PTR_TO_GLOBALS(xzalloc(sizeof(G)));
//} while (0)


/**********************************************************************/
#define LZOP_VERSION            0x1010
//#define LZOP_VERSION_STRING     "1.01"
//#define LZOP_VERSION_DATE       "Apr 27th 2003"

#define OPTION_STRING "cfvdt123456789CF"

enum {
	OPT_STDOUT      = (1 << 0),
	OPT_FORCE       = (1 << 1),
	OPT_VERBOSE     = (1 << 2),
	OPT_DECOMPRESS  = (1 << 3),
	OPT_TEST        = (1 << 4),
	OPT_1           = (1 << 5),
	OPT_2           = (1 << 6),
	OPT_3           = (1 << 7),
	OPT_4           = (1 << 8),
	OPT_5           = (1 << 9),
	OPT_6           = (1 << 10),
	OPT_789         = (7 << 11),
	OPT_7           = (1 << 11),
	OPT_8           = (1 << 12),
	OPT_C           = (1 << 14),
	OPT_F           = (1 << 15),
};

/**********************************************************************/
// adler32 checksum
// adapted from free code by Mark Adler <madler@alumni.caltech.edu>
// see http://www.zlib.org/
/**********************************************************************/
static FAST_FUNC uint32_t
lzo_adler32(uint32_t adler, const uint8_t* buf, unsigned len)
{
	enum {
		LZO_BASE = 65521, /* largest prime smaller than 65536 */
		/* NMAX is the largest n such that
		 * 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
		LZO_NMAX = 5552,
	};
	uint32_t s1 = adler & 0xffff;
	uint32_t s2 = (adler >> 16) & 0xffff;
	unsigned k;

	if (buf == NULL)
		return 1;

	while (len > 0) {
		k = len < LZO_NMAX ? (unsigned) len : LZO_NMAX;
		len -= k;
		if (k != 0) do {
			s1 += *buf++;
			s2 += s1;
		} while (--k > 0);
		s1 %= LZO_BASE;
		s2 %= LZO_BASE;
	}
	return (s2 << 16) | s1;
}

static FAST_FUNC uint32_t
lzo_crc32(uint32_t c, const uint8_t* buf, unsigned len)
{
	uint32_t crc;

	if (buf == NULL)
		return 0;

	crc = ~c;
	if (len != 0) do {
	crc = G.lzo_crc32_table[((int)crc ^ *buf) & 0xff] ^ (crc >> 8);
		buf += 1;
		len -= 1;
	} while (len > 0);

	return ~crc;
}

/**********************************************************************/
static void init_chksum(chksum_t *ct)
{
	ct->f_adler32 = ADLER32_INIT_VALUE;
	ct->f_crc32 = CRC32_INIT_VALUE;
}

static void add_bytes_to_chksum(chksum_t *ct, const void* buf, int cnt)
{
	/* We need to handle the two checksums at once, because at the
	 * beginning of the header, we don't know yet which one we'll
	 * eventually need */
	ct->f_adler32 = lzo_adler32(ct->f_adler32, (const uint8_t*)buf, cnt);
	ct->f_crc32 = lzo_crc32(ct->f_crc32, (const uint8_t*)buf, cnt);
}

static uint32_t chksum_getresult(chksum_t *ct, const header_t *h)
{
	return (h->flags & F_H_CRC32) ? ct->f_crc32 : ct->f_adler32;
}

/**********************************************************************/
static uint32_t read32(void)
{
	uint32_t v;
	xread(0, &v, 4);
	return ntohl(v);
}

static void write32(uint32_t v)
{
	v = htonl(v);
	xwrite(1, &v, 4);
}

static void f_write(const void* buf, int cnt)
{
	xwrite(1, buf, cnt);
	add_bytes_to_chksum(&G.chksum_out, buf, cnt);
}

static void f_read(void* buf, int cnt)
{
	xread(0, buf, cnt);
	add_bytes_to_chksum(&G.chksum_in, buf, cnt);
}

static int f_read8(void)
{
	uint8_t v;
	f_read(&v, 1);
	return v;
}

static void f_write8(uint8_t v)
{
	f_write(&v, 1);
}

static unsigned f_read16(void)
{
	uint16_t v;
	f_read(&v, 2);
	return ntohs(v);
}

static void f_write16(uint16_t v)
{
	v = htons(v);
	f_write(&v, 2);
}

static uint32_t f_read32(void)
{
	uint32_t v;
	f_read(&v, 4);
	return ntohl(v);
}

static void f_write32(uint32_t v)
{
	v = htonl(v);
	f_write(&v, 4);
}

/**********************************************************************/
static int lzo_get_method(header_t *h)
{
	/* check method */
	if (h->method == M_LZO1X_1) {
		if (h->level == 0)
			h->level = 3;
	} else if (h->method == M_LZO1X_1_15) {
		if (h->level == 0)
			h->level = 1;
	} else if (h->method == M_LZO1X_999) {
		if (h->level == 0)
			h->level = 9;
	} else
		return -1;		/* not a LZO method */

	/* check compression level */
	if (h->level < 1 || h->level > 9)
		return 15;

	return 0;
}

/**********************************************************************/
#define LZO_BLOCK_SIZE	(256 * 1024l)
#define MAX_BLOCK_SIZE	(64 * 1024l * 1024l)	/* DO NOT CHANGE */

/* LZO may expand uncompressible data by a small amount */
#define MAX_COMPRESSED_SIZE(x)	((x) + (x) / 16 + 64 + 3)

/**********************************************************************/
// compress a file
/**********************************************************************/
static smallint lzo_compress(const header_t *h)
{
	unsigned block_size = LZO_BLOCK_SIZE;
	int r = 0; /* LZO_E_OK */
	uint8_t *const b1 = xzalloc(block_size);
	uint8_t *const b2 = xzalloc(MAX_COMPRESSED_SIZE(block_size));
	unsigned src_len = 0, dst_len = 0;
	uint32_t d_adler32 = ADLER32_INIT_VALUE;
	uint32_t d_crc32 = CRC32_INIT_VALUE;
	int l;
	smallint ok = 1;
	uint8_t *wrk_mem = NULL;

	if (h->method == M_LZO1X_1)
		wrk_mem = xzalloc(LZO1X_1_MEM_COMPRESS);
	else if (h->method == M_LZO1X_1_15)
		wrk_mem = xzalloc(LZO1X_1_15_MEM_COMPRESS);
	else if (h->method == M_LZO1X_999)
		wrk_mem = xzalloc(LZO1X_999_MEM_COMPRESS);

	for (;;) {
		/* read a block */
		l = full_read(0, b1, block_size);
		src_len = (l > 0 ? l : 0);

		/* write uncompressed block size */
		write32(src_len);

		/* exit if last block */
		if (src_len == 0)
			break;

		/* compute checksum of uncompressed block */
		if (h->flags & F_ADLER32_D)
			d_adler32 = lzo_adler32(ADLER32_INIT_VALUE, b1, src_len);
		if (h->flags & F_CRC32_D)
			d_crc32 = lzo_crc32(CRC32_INIT_VALUE, b1, src_len);

		/* compress */
		if (h->method == M_LZO1X_1)
			r = lzo1x_1_compress(b1, src_len, b2, &dst_len, wrk_mem);
		else if (h->method == M_LZO1X_1_15)
			r = lzo1x_1_15_compress(b1, src_len, b2, &dst_len, wrk_mem);
#if ENABLE_LZOP_COMPR_HIGH
		else if (h->method == M_LZO1X_999)
			r = lzo1x_999_compress_level(b1, src_len, b2, &dst_len,
						wrk_mem, h->level);
#endif
		else
			bb_error_msg_and_die("internal error");

		if (r != 0) /* not LZO_E_OK */
			bb_error_msg_and_die("internal error - compression failed");

		/* write compressed block size */
		if (dst_len < src_len) {
			/* optimize */
			if (h->method == M_LZO1X_999) {
				unsigned new_len = src_len;
				r = lzo1x_optimize(b2, dst_len, b1, &new_len, NULL);
				if (r != 0 /*LZO_E_OK*/ || new_len != src_len)
					bb_error_msg_and_die("internal error - optimization failed");
			}
			write32(dst_len);
		} else {
			/* data actually expanded => store data uncompressed */
			write32(src_len);
		}

		/* write checksum of uncompressed block */
		if (h->flags & F_ADLER32_D)
			write32(d_adler32);
		if (h->flags & F_CRC32_D)
			write32(d_crc32);

		if (dst_len < src_len) {
			/* write checksum of compressed block */
			if (h->flags & F_ADLER32_C)
				write32(lzo_adler32(ADLER32_INIT_VALUE, b2,
							dst_len));
			if (h->flags & F_CRC32_C)
				write32(lzo_crc32(CRC32_INIT_VALUE, b2, dst_len));
			/* write compressed block data */
			xwrite(1, b2, dst_len);
		} else {
			/* write uncompressed block data */
			xwrite(1, b1, src_len);
		}
	}

	free(wrk_mem);
	free(b1);
	free(b2);
	return ok;
}

static void lzo_check(uint32_t FAST_FUNC (*fn)(uint32_t, const uint8_t*, unsigned),
		uint32_t ref, uint32_t init,
		uint8_t* buf, unsigned len)
{
	uint32_t c = fn(init, buf, len);
	if (c != ref)
		bb_error_msg_and_die("checksum error");
}

/**********************************************************************/
// decompress a file
/**********************************************************************/
static smallint lzo_decompress(const header_t *h)
{
	unsigned block_size = LZO_BLOCK_SIZE;
	int r;
	uint32_t src_len, dst_len;
	uint32_t c_adler32 = ADLER32_INIT_VALUE;
	uint32_t d_adler32 = ADLER32_INIT_VALUE;
	uint32_t c_crc32 = CRC32_INIT_VALUE, d_crc32 = CRC32_INIT_VALUE;
	smallint ok = 1;
	uint8_t *b1;
	uint32_t mcs_block_size = MAX_COMPRESSED_SIZE(block_size);
	uint8_t *b2 = NULL;

	for (;;) {
		uint8_t *dst;

		/* read uncompressed block size */
		dst_len = read32();

		/* exit if last block */
		if (dst_len == 0)
			break;

		/* error if split file */
		if (dst_len == 0xffffffffL)
			/* should not happen - not yet implemented */
			bb_error_msg_and_die("this file is a split lzop file");

		if (dst_len > MAX_BLOCK_SIZE)
			bb_error_msg_and_die("lzop file corrupted");

		/* read compressed block size */
		src_len = read32();
		if (src_len <= 0 || src_len > dst_len)
			bb_error_msg_and_die("lzop file corrupted");

		if (dst_len > block_size) {
			if (b2) {
//FIXME!
				b2 = NULL;
				free(b2);
			}
			block_size = dst_len;
			mcs_block_size = MAX_COMPRESSED_SIZE(block_size);
		}

		/* read checksum of uncompressed block */
		if (h->flags & F_ADLER32_D)
			d_adler32 = read32();
		if (h->flags & F_CRC32_D)
			d_crc32 = read32();

		/* read checksum of compressed block */
		if (src_len < dst_len) {
			if (h->flags & F_ADLER32_C)
				c_adler32 = read32();
			if (h->flags & F_CRC32_C)
				c_crc32 = read32();
		}

		if (b2 == NULL)
			b2 = xzalloc(mcs_block_size);
		/* read the block into the end of our buffer */
		b1 = b2 + mcs_block_size - src_len;
		xread(0, b1, src_len);

		if (src_len < dst_len) {
			unsigned d = dst_len;

			if (!(option_mask32 & OPT_F)) {
				/* verify checksum of compressed block */
				if (h->flags & F_ADLER32_C)
					lzo_check(lzo_adler32, c_adler32,
							ADLER32_INIT_VALUE,
							b1, src_len);
				if (h->flags & F_CRC32_C)
					lzo_check(lzo_crc32, c_crc32,
							CRC32_INIT_VALUE,
							b1, src_len);
			}

			/* decompress */
//			if (option_mask32 & OPT_F)
//				r = lzo1x_decompress(b1, src_len, b2, &d, NULL);
//			else
				r = lzo1x_decompress_safe(b1, src_len, b2, &d, NULL);

			if (r != 0 /*LZO_E_OK*/ || dst_len != d) {
				bb_error_msg_and_die("corrupted compressed data");
			}
			dst = b2;
		} else {
			/* "stored" block => no decompression */
			dst = b1;
		}

		if (!(option_mask32 & OPT_F)) {
			/* verify checksum of uncompressed block */
			if (h->flags & F_ADLER32_D)
				lzo_check(lzo_adler32, d_adler32, ADLER32_INIT_VALUE,
					  dst, dst_len);
			if (h->flags & F_CRC32_D)
				lzo_check(lzo_crc32, d_crc32, CRC32_INIT_VALUE,
					  dst, dst_len);
		}

		/* write uncompressed block data */
		xwrite(1, dst, dst_len);
	}

	free(b2);
	return ok;
}

/**********************************************************************/
// lzop file signature (shamelessly borrowed from PNG)
/**********************************************************************/
/*
 * The first nine bytes of a lzop file always contain the following values:
 *
 *                                 0   1   2   3   4   5   6   7   8
 *                               --- --- --- --- --- --- --- --- ---
 * (hex)                          89  4c  5a  4f  00  0d  0a  1a  0a
 * (decimal)                     137  76  90  79   0  13  10  26  10
 * (C notation - ASCII)         \211   L   Z   O  \0  \r  \n \032 \n
 */

/* (vda) comparison with lzop v1.02rc1 ("lzop -1 <FILE" cmd):
 * Only slight differences in header:
 * -00000000  89 4c 5a 4f 00 0d 0a 1a 0a 10 20 20 20 09 40 02
 * +00000000  89 4c 5a 4f 00 0d 0a 1a 0a 10 10 20 30 09 40 02
 *                                       ^^^^^ ^^^^^
 *                                     version lib_version
 * -00000010  01 03 00 00 0d 00 00 81 a4 49 f7 a6 3f 00 00 00
 * +00000010  01 03 00 00 01 00 00 00 00 00 00 00 00 00 00 00
 *               ^^^^^^^^^^^ ^^^^^^^^^^^ ^^^^^^^^^^^
 *               flags       mode        mtime
 * -00000020  00 00 2d 67 04 17 00 04 00 00 00 03 ed ec 9d 6d
 * +00000020  00 00 10 5f 00 c1 00 04 00 00 00 03 ed ec 9d 6d
 *                  ^^^^^^^^^^^
 *                  chksum_out
 * The rest is identical.
*/
static const unsigned char lzop_magic[9] = {
	0x89, 0x4c, 0x5a, 0x4f, 0x00, 0x0d, 0x0a, 0x1a, 0x0a
};

/* This coding is derived from Alexander Lehmann's pngcheck code. */
static void check_magic(void)
{
	unsigned char magic[sizeof(lzop_magic)];
	xread(0, magic, sizeof(magic));
	if (memcmp(magic, lzop_magic, sizeof(lzop_magic)) != 0)
		bb_error_msg_and_die("bad magic number");
}

/**********************************************************************/
// lzop file header
/**********************************************************************/
static void write_header(const header_t *h)
{
	int l;

	xwrite(1, lzop_magic, sizeof(lzop_magic));

	init_chksum(&G.chksum_out);

	f_write16(h->version);
	f_write16(h->lib_version);
	f_write16(h->version_needed_to_extract);
	f_write8(h->method);
	f_write8(h->level);
	f_write32(h->flags);
	f_write32(h->mode);
	f_write32(h->mtime);
	f_write32(h->gmtdiff);

	l = (int) strlen(h->name);
	f_write8(l);
	if (l)
		f_write(h->name, l);

	f_write32(chksum_getresult(&G.chksum_out, h));
}

static int read_header(header_t *h)
{
	int r;
	int l;
	uint32_t checksum;

	memset(h, 0, sizeof(*h));
	h->version_needed_to_extract = 0x0900;	/* first lzop version */
	h->level = 0;

	init_chksum(&G.chksum_in);

	h->version = f_read16();
	if (h->version < 0x0900)
		return 3;
	h->lib_version = f_read16();
	if (h->version >= 0x0940) {
		h->version_needed_to_extract = f_read16();
		if (h->version_needed_to_extract > LZOP_VERSION)
			return 16;
		if (h->version_needed_to_extract < 0x0900)
			return 3;
	}
	h->method = f_read8();
	if (h->version >= 0x0940)
		h->level = f_read8();
	h->flags = f_read32();
	if (h->flags & F_H_FILTER)
		return 16; /* filter not supported */
	h->mode = f_read32();
	h->mtime = f_read32();
	if (h->version >= 0x0940)
		h->gmtdiff = f_read32();

	l = f_read8();
	if (l > 0)
		f_read(h->name, l);
	h->name[l] = 0;

	checksum = chksum_getresult(&G.chksum_in, h);
	h->header_checksum = f_read32();
	if (h->header_checksum != checksum)
		return 2;

	if (h->method <= 0)
		return 14;
	r = lzo_get_method(h);
	if (r != 0)
		return r;

	/* check reserved flags */
	if (h->flags & F_RESERVED)
		return -13;

	/* skip extra field [not used yet] */
	if (h->flags & F_H_EXTRA_FIELD) {
		uint32_t k;

		/* note: the checksum also covers the length */
		init_chksum(&G.chksum_in);
		h->extra_field_len = f_read32();
		for (k = 0; k < h->extra_field_len; k++)
			f_read8();
		checksum = chksum_getresult(&G.chksum_in, h);
		h->extra_field_checksum = f_read32();
		if (h->extra_field_checksum != checksum)
			return 3;
	}

	return 0;
}

static void p_header(header_t *h)
{
	int r;

	r = read_header(h);
	if (r == 0)
		return;
	bb_error_msg_and_die("header_error %d", r);
}

/**********************************************************************/
// compress
/**********************************************************************/
static void lzo_set_method(header_t *h)
{
	int level = 1;

	if (option_mask32 & OPT_1) {
		h->method = M_LZO1X_1_15;
	} else if (option_mask32 & OPT_789) {
#if ENABLE_LZOP_COMPR_HIGH
		h->method = M_LZO1X_999;
		if (option_mask32 & OPT_7)
			level = 7;
		else if (option_mask32 & OPT_8)
			level = 8;
		else
			level = 9;
#else
		bb_error_msg_and_die("high compression not compiled in");
#endif
	} else { /* levels 2..6 or none (defaults to level 3) */
		h->method = M_LZO1X_1;
		level = 5; /* levels 2-6 are actually the same */
	}

	h->level = level;
}

static smallint do_lzo_compress(void)
{
	header_t header;

#define h (&header)
	memset(h, 0, sizeof(*h));

	lzo_set_method(h);

	h->version = (LZOP_VERSION & 0xffff);
	h->version_needed_to_extract = 0x0940;
	h->lib_version = lzo_version() & 0xffff;

	h->flags = (F_OS & F_OS_MASK) | (F_CS & F_CS_MASK);

	if (!(option_mask32 & OPT_F) || h->method == M_LZO1X_999) {
		h->flags |= F_ADLER32_D;
		if (option_mask32 & OPT_C)
			h->flags |= F_ADLER32_C;
	}
	write_header(h);
	return lzo_compress(h);
#undef h
}

/**********************************************************************/
// decompress
/**********************************************************************/
static smallint do_lzo_decompress(void)
{
	header_t header;

	check_magic();
	p_header(&header);
	return lzo_decompress(&header);
}

static char* make_new_name_lzop(char *filename)
{
	if (option_mask32 & OPT_DECOMPRESS) {
		char *extension = strrchr(filename, '.');
		if (!extension || strcmp(extension + 1, "lzo") != 0)
			return xasprintf("%s.out", filename);
		*extension = '\0';
		return filename;
	}
	return xasprintf("%s.lzo", filename);
}

static IF_DESKTOP(long long) int pack_lzop(unpack_info_t *info UNUSED_PARAM)
{
	if (option_mask32 & OPT_DECOMPRESS)
		return do_lzo_decompress();
	return do_lzo_compress();
}

int lzop_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int lzop_main(int argc UNUSED_PARAM, char **argv)
{
	getopt32(argv, OPTION_STRING);
	argv += optind;
	/* lzopcat? */
	if (applet_name[4] == 'c')
		option_mask32 |= (OPT_STDOUT | OPT_DECOMPRESS);
	/* unlzop? */
	if (applet_name[0] == 'u')
		option_mask32 |= OPT_DECOMPRESS;

	G.lzo_crc32_table = crc32_filltable(NULL, 0);
	return bbunpack(argv, make_new_name_lzop, pack_lzop);
}