aboutsummaryrefslogtreecommitdiff
path: root/src/liblzma/common/string_conversion.c
blob: 0bc459bc3878ddf0389a898cd31e3495119c80da (plain) (blame)
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
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
///////////////////////////////////////////////////////////////////////////////
//
/// \file       string_conversion.c
/// \brief      Conversion of strings to filter chain and vice versa
//
//  Author:     Lasse Collin
//
//  This file has been put into the public domain.
//  You can do whatever you want with this file.
//
///////////////////////////////////////////////////////////////////////////////

#include "filter_common.h"


/////////////////////
// String building //
/////////////////////

/// How much memory to allocate for strings. For now, no realloc is used
/// so this needs to be big enough even though there of course is
/// an overflow check still.
///
/// FIXME? Using a fixed size is wasteful if the application doesn't free
/// the string fairly quickly but this can be improved later if needed.
#define STR_ALLOC_SIZE 800


typedef struct {
	char *buf;
	size_t pos;
} lzma_str;


static lzma_ret
str_init(lzma_str *str, const lzma_allocator *allocator)
{
	str->buf = lzma_alloc(STR_ALLOC_SIZE, allocator);
	if (str->buf == NULL)
		return LZMA_MEM_ERROR;

	str->pos = 0;
	return LZMA_OK;
}


static void
str_free(lzma_str *str, const lzma_allocator *allocator)
{
	lzma_free(str->buf, allocator);
	return;
}


static bool
str_is_full(const lzma_str *str)
{
	return str->pos == STR_ALLOC_SIZE - 1;
}


static lzma_ret
str_finish(char **dest, lzma_str *str, const lzma_allocator *allocator)
{
	if (str_is_full(str)) {
		// The preallocated buffer was too small.
		// This shouldn't happen as STR_ALLOC_SIZE should
		// be adjusted if new filters are added.
		lzma_free(str->buf, allocator);
		*dest = NULL;
		assert(0);
		return LZMA_PROG_ERROR;
	}

	str->buf[str->pos] = '\0';
	*dest = str->buf;
	return LZMA_OK;
}


static void
str_append_str(lzma_str *str, const char *s)
{
	const size_t len = strlen(s);
	const size_t limit = STR_ALLOC_SIZE - 1 - str->pos;
	const size_t copy_size = my_min(len, limit);

	memcpy(str->buf + str->pos, s, copy_size);
	str->pos += copy_size;
	return;
}


static void
str_append_u32(lzma_str *str, uint32_t v, bool use_byte_suffix)
{
	if (v == 0) {
		str_append_str(str, "0");
	} else {
		// NOTE: Don't use plain "B" because xz and the parser in this
		// file don't support it and at glance it may look like 8
		// (there cannot be a space before the suffix).
		static const char suffixes[4][4] = { "", "KiB", "MiB", "GiB" };

		size_t suf = 0;
		if (use_byte_suffix) {
			while ((v & 1023) == 0
					&& suf < ARRAY_SIZE(suffixes) - 1) {
				v >>= 10;
				++suf;
			}
		}

		// UINT32_MAX in base 10 would need 10 + 1 bytes. Remember
		// that initializing to "" initializes all elements to
		// zero so '\0'-termination gets handled by this.
		char buf[16] = "";
		size_t pos = sizeof(buf) - 1;

		do {
			buf[--pos] = '0' + (v % 10);
			v /= 10;
		} while (v != 0);

		str_append_str(str, buf + pos);
		str_append_str(str, suffixes[suf]);
	}

	return;
}


//////////////////////////////////////////////
// Parsing and stringification declarations //
//////////////////////////////////////////////

/// Maximum length for filter and option names.
/// 11 chars + terminating '\0' + sizeof(uint32_t) = 16 bytes
#define NAME_LEN_MAX 11


/// For option_map.flags: Use .u.map to do convert the input value
/// to an integer. Without this flag, .u.range.{min,max} are used
/// as the allowed range for the integer.
#define OPTMAP_USE_NAME_VALUE_MAP 0x01

/// For option_map.flags: Allow KiB/MiB/GiB in input string and use them in
/// the stringified output if the value is an exact multiple of these.
/// This is used e.g. for LZMA1/2 dictionary size.
#define OPTMAP_USE_BYTE_SUFFIX 0x02

/// For option_map.flags: If the integer value is zero then this option
/// won't be included in the stringified output. It's used e.g. for
/// BCJ filter start offset which usually is zero.
#define OPTMAP_NO_STRFY_ZERO 0x04

/// Possible values for option_map.type. Since OPTMAP_TYPE_UINT32 is 0,
/// it doesn't need to be specified in the initializers as it is
/// the implicit value.
enum {
	OPTMAP_TYPE_UINT32,
	OPTMAP_TYPE_LZMA_MODE,
	OPTMAP_TYPE_LZMA_MATCH_FINDER,
	OPTMAP_TYPE_LZMA_PRESET,
};


/// This is for mapping string values in options to integers.
/// The last element of an array must have "" as the name.
/// It's used e.g. for match finder names in LZMA1/2.
typedef struct {
	const char name[NAME_LEN_MAX + 1];
	const uint32_t value;
} name_value_map;


/// Each filter that has options needs an array of option_map structures.
/// The array doesn't need to be terminated as the functions take the
/// length of the array as an argument.
///
/// When converting a string to filter options structure, option values
/// will be handled in a few different ways:
///
/// (1) If .type equals OPTMAP_TYPE_LZMA_PRESET then LZMA1/2 preset string
///     is handled specially.
///
/// (2) If .flags has OPTMAP_USE_NAME_VALUE_MAP set then the string is
///     converted to an integer using the name_value_map pointed by .u.map.
///     The last element in .u.map must have .name = "" as the terminator.
///
/// (3) Otherwise the string is treated as a non-negative unsigned decimal
///     integer which must be in the range set in .u.range. If .flags has
///     OPTMAP_USE_BYTE_SUFFIX then KiB, MiB, and GiB suffixes are allowed.
///
/// The integer value from (2) or (3) is then stored to filter_options
/// at the offset specified in .offset using the type specified in .type
/// (default is uint32_t).
///
/// Stringifying a filter is done by processing a given number of options
/// in order from the beginning of an option_map array. The integer is
/// read from filter_options at .offset using the type from .type.
///
/// If the integer is zero and .flags has OPTMAP_NO_STRFY_ZERO then the
/// option is skipped.
///
/// If .flags has OPTMAP_USE_NAME_VALUE_MAP set then .u.map will be used
/// to convert the option to a string. If the map doesn't contain a string
/// for the integer value then "UNKNOWN" is used.
///
/// If .flags doesn't have OPTMAP_USE_NAME_VALUE_MAP set then the integer is
/// converted to a decimal value. If OPTMAP_USE_BYTE_SUFFIX is used then KiB,
/// MiB, or GiB suffix is used if the value is an exact multiple of these.
/// Plain "B" suffix is never used.
typedef struct {
	char name[NAME_LEN_MAX + 1];
	uint8_t type;
	uint8_t flags;
	uint16_t offset;

	union {
		struct {
			uint32_t min;
			uint32_t max;
		} range;

		const name_value_map *map;
	} u;
} option_map;


static const char *parse_options(const char **const str, const char *str_end,
		void *filter_options,
		const option_map *const optmap, const size_t optmap_size);


/////////
// BCJ //
/////////

#if defined(HAVE_ENCODER_X86) \
		|| defined(HAVE_DECODER_X86) \
		|| defined(HAVE_ENCODER_ARM) \
		|| defined(HAVE_DECODER_ARM) \
		|| defined(HAVE_ENCODER_ARMTHUMB) \
		|| defined(HAVE_DECODER_ARMTHUMB) \
		|| defined(HAVE_ENCODER_ARM64) \
		|| defined(HAVE_DECODER_ARM64) \
		|| defined(HAVE_ENCODER_POWERPC) \
		|| defined(HAVE_DECODER_POWERPC) \
		|| defined(HAVE_ENCODER_IA64) \
		|| defined(HAVE_DECODER_IA64) \
		|| defined(HAVE_ENCODER_SPARC) \
		|| defined(HAVE_DECODER_SPARC) \
		|| defined(HAVE_ENCODER_RISCV) \
		|| defined(HAVE_DECODER_RISCV)
static const option_map bcj_optmap[] = {
	{
		.name = "start",
		.flags = OPTMAP_NO_STRFY_ZERO | OPTMAP_USE_BYTE_SUFFIX,
		.offset = offsetof(lzma_options_bcj, start_offset),
		.u.range.min = 0,
		.u.range.max = UINT32_MAX,
	}
};


static const char *
parse_bcj(const char **const str, const char *str_end, void *filter_options)
{
	// filter_options was zeroed on allocation and that is enough
	// for the default value.
	return parse_options(str, str_end, filter_options,
			bcj_optmap, ARRAY_SIZE(bcj_optmap));
}
#endif


///////////
// Delta //
///////////

#if defined(HAVE_ENCODER_DELTA) || defined(HAVE_DECODER_DELTA)
static const option_map delta_optmap[] = {
	{
		.name = "dist",
		.offset = offsetof(lzma_options_delta, dist),
		.u.range.min = LZMA_DELTA_DIST_MIN,
		.u.range.max = LZMA_DELTA_DIST_MAX,
	}
};


static const char *
parse_delta(const char **const str, const char *str_end, void *filter_options)
{
	lzma_options_delta *opts = filter_options;
	opts->type = LZMA_DELTA_TYPE_BYTE;
	opts->dist = LZMA_DELTA_DIST_MIN;

	return parse_options(str, str_end, filter_options,
			delta_optmap, ARRAY_SIZE(delta_optmap));
}
#endif


///////////////////
// LZMA1 & LZMA2 //
///////////////////

/// Help string for presets
#define LZMA12_PRESET_STR "0-9[e]"


static const char *
parse_lzma12_preset(const char **const str, const char *str_end,
		uint32_t *preset)
{
	assert(*str < str_end);
	*preset = (uint32_t)(**str - '0');

	// NOTE: Remember to update LZMA12_PRESET_STR if this is modified!
	while (++*str < str_end) {
		switch (**str) {
		case 'e':
			*preset |= LZMA_PRESET_EXTREME;
			break;

		default:
			return "Unsupported preset flag";
		}
	}

	return NULL;
}


static const char *
set_lzma12_preset(const char **const str, const char *str_end,
		void *filter_options)
{
	uint32_t preset;
	const char *errmsg = parse_lzma12_preset(str, str_end, &preset);
	if (errmsg != NULL)
		return errmsg;

	lzma_options_lzma *opts = filter_options;
	if (lzma_lzma_preset(opts, preset))
		return "Unsupported preset";

	return NULL;
}


static const name_value_map lzma12_mode_map[] = {
	{ "fast",   LZMA_MODE_FAST },
	{ "normal", LZMA_MODE_NORMAL },
	{ "",       0 }
};


static const name_value_map lzma12_mf_map[] = {
	{ "hc3", LZMA_MF_HC3 },
	{ "hc4", LZMA_MF_HC4 },
	{ "bt2", LZMA_MF_BT2 },
	{ "bt3", LZMA_MF_BT3 },
	{ "bt4", LZMA_MF_BT4 },
	{ "",    0 }
};


static const option_map lzma12_optmap[] = {
	{
		.name = "preset",
		.type = OPTMAP_TYPE_LZMA_PRESET,
	}, {
		.name = "dict",
		.flags = OPTMAP_USE_BYTE_SUFFIX,
		.offset = offsetof(lzma_options_lzma, dict_size),
		.u.range.min = LZMA_DICT_SIZE_MIN,
		// FIXME? The max is really max for encoding but decoding
		// would allow 4 GiB - 1 B.
		.u.range.max = (UINT32_C(1) << 30) + (UINT32_C(1) << 29),
	}, {
		.name = "lc",
		.offset = offsetof(lzma_options_lzma, lc),
		.u.range.min = LZMA_LCLP_MIN,
		.u.range.max = LZMA_LCLP_MAX,
	}, {
		.name = "lp",
		.offset = offsetof(lzma_options_lzma, lp),
		.u.range.min = LZMA_LCLP_MIN,
		.u.range.max = LZMA_LCLP_MAX,
	}, {
		.name = "pb",
		.offset = offsetof(lzma_options_lzma, pb),
		.u.range.min = LZMA_PB_MIN,
		.u.range.max = LZMA_PB_MAX,
	}, {
		.name = "mode",
		.type = OPTMAP_TYPE_LZMA_MODE,
		.flags = OPTMAP_USE_NAME_VALUE_MAP,
		.offset = offsetof(lzma_options_lzma, mode),
		.u.map = lzma12_mode_map,
	}, {
		.name = "nice",
		.offset = offsetof(lzma_options_lzma, nice_len),
		.u.range.min = 2,
		.u.range.max = 273,
	}, {
		.name = "mf",
		.type = OPTMAP_TYPE_LZMA_MATCH_FINDER,
		.flags = OPTMAP_USE_NAME_VALUE_MAP,
		.offset = offsetof(lzma_options_lzma, mf),
		.u.map = lzma12_mf_map,
	}, {
		.name = "depth",
		.offset = offsetof(lzma_options_lzma, depth),
		.u.range.min = 0,
		.u.range.max = UINT32_MAX,
	}
};


static const char *
parse_lzma12(const char **const str, const char *str_end, void *filter_options)
{
	lzma_options_lzma *opts = filter_options;

	// It cannot fail.
	const bool preset_ret = lzma_lzma_preset(opts, LZMA_PRESET_DEFAULT);
	assert(!preset_ret);
	(void)preset_ret;

	const char *errmsg = parse_options(str, str_end, filter_options,
			lzma12_optmap, ARRAY_SIZE(lzma12_optmap));
	if (errmsg != NULL)
		return errmsg;

	if (opts->lc + opts->lp > LZMA_LCLP_MAX)
		return "The sum of lc and lp must not exceed 4";

	return NULL;
}


/////////////////////////////////////////
// Generic parsing and stringification //
/////////////////////////////////////////

static const struct {
	/// Name of the filter
	char name[NAME_LEN_MAX + 1];

	/// For lzma_str_to_filters:
	/// Size of the filter-specific options structure.
	uint32_t opts_size;

	/// Filter ID
	lzma_vli id;

	/// For lzma_str_to_filters:
	/// Function to parse the filter-specific options. The filter_options
	/// will already have been allocated using lzma_alloc_zero().
	const char *(*parse)(const char **str, const char *str_end,
			void *filter_options);

	/// For lzma_str_from_filters:
	/// If the flag LZMA_STR_ENCODER is used then the first
	/// strfy_encoder elements of optmap are stringified.
	/// With LZMA_STR_DECODER strfy_decoder is used.
	/// Currently encoders use all options that decoders do but if
	/// that changes then this needs to be changed too, for example,
	/// add a new OPTMAP flag to skip printing some decoder-only options.
	const option_map *optmap;
	uint8_t strfy_encoder;
	uint8_t strfy_decoder;

	/// For lzma_str_from_filters:
	/// If true, lzma_filter.options is allowed to be NULL. In that case,
	/// only the filter name is printed without any options.
	bool allow_null;

} filter_name_map[] = {
#if defined (HAVE_ENCODER_LZMA1) || defined(HAVE_DECODER_LZMA1)
	{ "lzma1",        sizeof(lzma_options_lzma),  LZMA_FILTER_LZMA1,
	  &parse_lzma12,  lzma12_optmap, 9, 5, false },
#endif

#if defined(HAVE_ENCODER_LZMA2) || defined(HAVE_DECODER_LZMA2)
	{ "lzma2",        sizeof(lzma_options_lzma),  LZMA_FILTER_LZMA2,
	  &parse_lzma12,  lzma12_optmap, 9, 2, false },
#endif

#if defined(HAVE_ENCODER_X86) || defined(HAVE_DECODER_X86)
	{ "x86",          sizeof(lzma_options_bcj),   LZMA_FILTER_X86,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_ARM) || defined(HAVE_DECODER_ARM)
	{ "arm",          sizeof(lzma_options_bcj),   LZMA_FILTER_ARM,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_ARMTHUMB) || defined(HAVE_DECODER_ARMTHUMB)
	{ "armthumb",     sizeof(lzma_options_bcj),   LZMA_FILTER_ARMTHUMB,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_ARM64) || defined(HAVE_DECODER_ARM64)
	{ "arm64",        sizeof(lzma_options_bcj),   LZMA_FILTER_ARM64,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_RISCV) || defined(HAVE_DECODER_RISCV)
	{ "riscv",        sizeof(lzma_options_bcj),   LZMA_FILTER_RISCV,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_POWERPC) || defined(HAVE_DECODER_POWERPC)
	{ "powerpc",      sizeof(lzma_options_bcj),   LZMA_FILTER_POWERPC,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_IA64) || defined(HAVE_DECODER_IA64)
	{ "ia64",         sizeof(lzma_options_bcj),   LZMA_FILTER_IA64,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_SPARC) || defined(HAVE_DECODER_SPARC)
	{ "sparc",        sizeof(lzma_options_bcj),   LZMA_FILTER_SPARC,
	  &parse_bcj,     bcj_optmap, 1, 1, true },
#endif

#if defined(HAVE_ENCODER_DELTA) || defined(HAVE_DECODER_DELTA)
	{ "delta",        sizeof(lzma_options_delta), LZMA_FILTER_DELTA,
	  &parse_delta,   delta_optmap, 1, 1, false },
#endif
};


/// Decodes options from a string for one filter (name1=value1,name2=value2).
/// Caller must have allocated memory for filter_options already and set
/// the initial default values. This is called from the filter-specific
/// parse_* functions.
///
/// The input string starts at *str and the address in str_end is the first
/// char that is not part of the string anymore. So no '\0' terminator is
/// used. *str is advanced every time something has been decoded successfully.
static const char *
parse_options(const char **const str, const char *str_end,
		void *filter_options,
		const option_map *const optmap, const size_t optmap_size)
{
	while (*str < str_end && **str != '\0') {
		// Each option is of the form name=value.
		// Commas (',') separate options. Extra commas are ignored.
		// Ignoring extra commas makes it simpler if an optional
		// option stored in a shell variable which can be empty.
		if (**str == ',') {
			++*str;
			continue;
		}

		// Find where the next name=value ends.
		const size_t str_len = (size_t)(str_end - *str);
		const char *name_eq_value_end = memchr(*str, ',', str_len);
		if (name_eq_value_end == NULL)
			name_eq_value_end = str_end;

		const char *equals_sign = memchr(*str, '=',
				(size_t)(name_eq_value_end - *str));

		// Fail if the '=' wasn't found or the option name is missing
		// (the first char is '=').
		if (equals_sign == NULL || **str == '=')
			return "Options must be 'name=value' pairs separated "
					"with commas";

		// Reject a too long option name so that the memcmp()
		// in the loop below won't read past the end of the
		// string in optmap[i].name.
		const size_t name_len = (size_t)(equals_sign - *str);
		if (name_len > NAME_LEN_MAX)
			return "Unknown option name";

		// Find the option name from optmap[].
		size_t i = 0;
		while (true) {
			if (i == optmap_size)
				return "Unknown option name";

			if (memcmp(*str, optmap[i].name, name_len) == 0
					&& optmap[i].name[name_len] == '\0')
				break;

			++i;
		}

		// The input string is good at least until the start of
		// the option value.
		*str = equals_sign + 1;

		// The code assumes that the option value isn't an empty
		// string so check it here.
		const size_t value_len = (size_t)(name_eq_value_end - *str);
		if (value_len == 0)
			return "Option value cannot be empty";

		// LZMA1/2 preset has its own parsing function.
		if (optmap[i].type == OPTMAP_TYPE_LZMA_PRESET) {
			const char *errmsg = set_lzma12_preset(str,
					name_eq_value_end, filter_options);
			if (errmsg != NULL)
				return errmsg;

			continue;
		}

		// It's an integer value.
		uint32_t v;
		if (optmap[i].flags & OPTMAP_USE_NAME_VALUE_MAP) {
			// The integer is picked from a string-to-integer map.
			//
			// Reject a too long value string so that the memcmp()
			// in the loop below won't read past the end of the
			// string in optmap[i].u.map[j].name.
			if (value_len > NAME_LEN_MAX)
				return "Invalid option value";

			const name_value_map *map = optmap[i].u.map;
			size_t j = 0;
			while (true) {
				// The array is terminated with an empty name.
				if (map[j].name[0] == '\0')
					return "Invalid option value";

				if (memcmp(*str, map[j].name, value_len) == 0
						&& map[j].name[value_len]
							== '\0') {
					v = map[j].value;
					break;
				}

				++j;
			}
		} else if (**str < '0' || **str > '9') {
			// Note that "max" isn't supported while it is
			// supported in xz. It's not useful here.
			return "Value is not a non-negative decimal integer";
		} else {
			// strtoul() has locale-specific behavior so it cannot
			// be relied on to get reproducible results since we
			// cannot change the locate in a thread-safe library.
			// It also needs '\0'-termination.
			//
			// Use a temporary pointer so that *str will point
			// to the beginning of the value string in case
			// an error occurs.
			const char *p = *str;
			v = 0;
			do {
				if (v > UINT32_MAX / 10)
					return "Value out of range";

				v *= 10;

				const uint32_t add = (uint32_t)(*p - '0');
				if (UINT32_MAX - add < v)
					return "Value out of range";

				v += add;
				++p;
			} while (p < name_eq_value_end
					&& *p >= '0' && *p <= '9');

			if (p < name_eq_value_end) {
				// Remember this position so that it can be
				// used for error messages that are
				// specifically about the suffix. (Out of
				// range values are about the whole value
				// and those error messages point to the
				// beginning of the number part,
				// not to the suffix.)
				const char *multiplier_start = p;

				// If multiplier suffix shouldn't be used
				// then don't allow them even if the value
				// would stay within limits. This is a somewhat
				// unnecessary check but it rejects silly
				// things like lzma2:pb=0MiB which xz allows.
				if ((optmap[i].flags & OPTMAP_USE_BYTE_SUFFIX)
						== 0) {
					*str = multiplier_start;
					return "This option does not support "
						"any integer suffixes";
				}

				uint32_t shift;

				switch (*p) {
				case 'k':
				case 'K':
					shift = 10;
					break;

				case 'm':
				case 'M':
					shift = 20;
					break;

				case 'g':
				case 'G':
					shift = 30;
					break;

				default:
					*str = multiplier_start;
					return "Invalid multiplier suffix "
							"(KiB, MiB, or GiB)";
				}

				++p;

				// Allow "M", "Mi", "MB", "MiB" and the same
				// for the other five characters from the
				// switch-statement above. All are handled
				// as base-2 (perhaps a mistake, perhaps not).
				// Note that 'i' and 'B' are case sensitive.
				if (p < name_eq_value_end && *p == 'i')
					++p;

				if (p < name_eq_value_end && *p == 'B')
					++p;

				// Now we must have no chars remaining.
				if (p < name_eq_value_end) {
					*str = multiplier_start;
					return "Invalid multiplier suffix "
							"(KiB, MiB, or GiB)";
				}

				if (v > (UINT32_MAX >> shift))
					return "Value out of range";

				v <<= shift;
			}

			if (v < optmap[i].u.range.min
					|| v > optmap[i].u.range.max)
				return "Value out of range";
		}

		// Set the value in filter_options. Enums are handled
		// specially since the underlying type isn't the same
		// as uint32_t on all systems.
		void *ptr = (char *)filter_options + optmap[i].offset;
		switch (optmap[i].type) {
		case OPTMAP_TYPE_LZMA_MODE:
			*(lzma_mode *)ptr = (lzma_mode)v;
			break;

		case OPTMAP_TYPE_LZMA_MATCH_FINDER:
			*(lzma_match_finder *)ptr = (lzma_match_finder)v;
			break;

		default:
			*(uint32_t *)ptr = v;
			break;
		}

		// This option has been successfully handled.
		*str = name_eq_value_end;
	}

	// No errors.
	return NULL;
}


/// Finds the name of the filter at the beginning of the string and
/// calls filter_name_map[i].parse() to decode the filter-specific options.
/// The caller must have set str_end so that exactly one filter and its
/// options are present without any trailing characters.
static const char *
parse_filter(const char **const str, const char *str_end, lzma_filter *filter,
		const lzma_allocator *allocator, bool only_xz)
{
	// Search for a colon or equals sign that would separate the filter
	// name from filter options. If neither is found, then the input
	// string only contains a filter name and there are no options.
	//
	// First assume that a colon or equals sign won't be found:
	const char *name_end = str_end;
	const char *opts_start = str_end;

	for (const char *p = *str; p < str_end; ++p) {
		if (*p == ':' || *p == '=') {
			name_end = p;

			// Filter options (name1=value1,name2=value2,...)
			// begin after the colon or equals sign.
			opts_start = p + 1;
			break;
		}
	}

	// Reject a too long filter name so that the memcmp()
	// in the loop below won't read past the end of the
	// string in filter_name_map[i].name.
	const size_t name_len = (size_t)(name_end - *str);
	if (name_len > NAME_LEN_MAX)
		return "Unknown filter name";

	for (size_t i = 0; i < ARRAY_SIZE(filter_name_map); ++i) {
		if (memcmp(*str, filter_name_map[i].name, name_len) == 0
				&& filter_name_map[i].name[name_len] == '\0') {
			if (only_xz && filter_name_map[i].id
					>= LZMA_FILTER_RESERVED_START)
				return "This filter cannot be used in "
						"the .xz format";

			// Allocate the filter-specific options and
			// initialize the memory with zeros.
			void *options = lzma_alloc_zero(
					filter_name_map[i].opts_size,
					allocator);
			if (options == NULL)
				return "Memory allocation failed";

			// Filter name was found so the input string is good
			// at least this far.
			*str = opts_start;

			const char *errmsg = filter_name_map[i].parse(
					str, str_end, options);
			if (errmsg != NULL) {
				lzma_free(options, allocator);
				return errmsg;
			}

			// *filter is modified only when parsing is successful.
			filter->id = filter_name_map[i].id;
			filter->options = options;
			return NULL;
		}
	}

	return "Unknown filter name";
}


/// Converts the string to a filter chain (array of lzma_filter structures).
///
/// *str is advanced every time something has been decoded successfully.
/// This way the caller knows where in the string a possible error occurred.
static const char *
str_to_filters(const char **const str, lzma_filter *filters, uint32_t flags,
		const lzma_allocator *allocator)
{
	const char *errmsg;

	// Skip leading spaces.
	while (**str == ' ')
		++*str;

	if (**str == '\0')
		return "Empty string is not allowed, "
				"try \"6\" if a default value is needed";

	// Detect the type of the string.
	//
	// A string beginning with a digit or a string beginning with
	// one dash and a digit are treated as presets. Trailing spaces
	// will be ignored too (leading spaces were already ignored above).
	//
	// For example, "6", "7  ", "-9e", or "  -3  " are treated as presets.
	// Strings like "-" or "- " aren't preset.
#define MY_IS_DIGIT(c) ((c) >= '0' && (c) <= '9')
	if (MY_IS_DIGIT(**str) || (**str == '-' && MY_IS_DIGIT((*str)[1]))) {
		if (**str == '-')
			++*str;

		// Ignore trailing spaces.
		const size_t str_len = strlen(*str);
		const char *str_end = memchr(*str, ' ', str_len);
		if (str_end != NULL) {
			// There is at least one trailing space. Check that
			// there are no chars other than spaces.
			for (size_t i = 1; str_end[i] != '\0'; ++i)
				if (str_end[i] != ' ')
					return "Unsupported preset";
		} else {
			// There are no trailing spaces. Use the whole string.
			str_end = *str + str_len;
		}

		uint32_t preset;
		errmsg = parse_lzma12_preset(str, str_end, &preset);
		if (errmsg != NULL)
			return errmsg;

		lzma_options_lzma *opts = lzma_alloc(sizeof(*opts), allocator);
		if (opts == NULL)
			return "Memory allocation failed";

		if (lzma_lzma_preset(opts, preset)) {
			lzma_free(opts, allocator);
			return "Unsupported preset";
		}

		filters[0].id = LZMA_FILTER_LZMA2;
		filters[0].options = opts;
		filters[1].id = LZMA_VLI_UNKNOWN;
		filters[1].options = NULL;

		return NULL;
	}

	// Not a preset so it must be a filter chain.
	//
	// If LZMA_STR_ALL_FILTERS isn't used we allow only filters that
	// can be used in .xz.
	const bool only_xz = (flags & LZMA_STR_ALL_FILTERS) == 0;

	// Use a temporary array so that we don't modify the caller-supplied
	// one until we know that no errors occurred.
	lzma_filter temp_filters[LZMA_FILTERS_MAX + 1];

	size_t i = 0;
	do {
		if (i == LZMA_FILTERS_MAX) {
			errmsg = "The maximum number of filters is four";
			goto error;
		}

		// Skip "--" if present.
		if ((*str)[0] == '-' && (*str)[1] == '-')
			*str += 2;

		// Locate the end of "filter:name1=value1,name2=value2",
		// stopping at the first "--" or a single space.
		const char *filter_end = *str;
		while (filter_end[0] != '\0') {
			if ((filter_end[0] == '-' && filter_end[1] == '-')
					|| filter_end[0] == ' ')
				break;

			++filter_end;
		}

		// Inputs that have "--" at the end or "-- " in the middle
		// will result in an empty filter name.
		if (filter_end == *str) {
			errmsg = "Filter name is missing";
			goto error;
		}

		errmsg = parse_filter(str, filter_end, &temp_filters[i],
				allocator, only_xz);
		if (errmsg != NULL)
			goto error;

		// Skip trailing spaces.
		while (**str == ' ')
			++*str;

		++i;
	} while (**str != '\0');

	// Seems to be good, terminate the array so that
	// basic validation can be done.
	temp_filters[i].id = LZMA_VLI_UNKNOWN;
	temp_filters[i].options = NULL;

	// Do basic validation if the application didn't prohibit it.
	if ((flags & LZMA_STR_NO_VALIDATION) == 0) {
		size_t dummy;
		const lzma_ret ret = lzma_validate_chain(temp_filters, &dummy);
		assert(ret == LZMA_OK || ret == LZMA_OPTIONS_ERROR);
		if (ret != LZMA_OK) {
			errmsg = "Invalid filter chain "
					"('lzma2' missing at the end?)";
			goto error;
		}
	}

	// All good. Copy the filters to the application supplied array.
	memcpy(filters, temp_filters, (i + 1) * sizeof(lzma_filter));
	return NULL;

error:
	// Free the filter options that were successfully decoded.
	while (i-- > 0)
		lzma_free(temp_filters[i].options, allocator);

	return errmsg;
}


extern LZMA_API(const char *)
lzma_str_to_filters(const char *str, int *error_pos, lzma_filter *filters,
		uint32_t flags, const lzma_allocator *allocator)
{
	if (str == NULL || filters == NULL)
		return "Unexpected NULL pointer argument(s) "
				"to lzma_str_to_filters()";

	// Validate the flags.
	const uint32_t supported_flags
			= LZMA_STR_ALL_FILTERS
			| LZMA_STR_NO_VALIDATION;

	if (flags & ~supported_flags)
		return "Unsupported flags to lzma_str_to_filters()";

	const char *used = str;
	const char *errmsg = str_to_filters(&used, filters, flags, allocator);

	if (error_pos != NULL) {
		const size_t n = (size_t)(used - str);
		*error_pos = n > INT_MAX ? INT_MAX : (int)n;
	}

	return errmsg;
}


/// Converts options of one filter to a string.
///
/// The caller must have already put the filter name in the destination
/// string. Since it is possible that no options will be needed, the caller
/// won't have put a delimiter character (':' or '=') in the string yet.
/// We will add it if at least one option will be added to the string.
static void
strfy_filter(lzma_str *dest, const char *delimiter,
		const option_map *optmap, size_t optmap_count,
		const void *filter_options)
{
	for (size_t i = 0; i < optmap_count; ++i) {
		// No attempt is made to reverse LZMA1/2 preset.
		if (optmap[i].type == OPTMAP_TYPE_LZMA_PRESET)
			continue;

		// All options have integer values, some just are mapped
		// to a string with a name_value_map. LZMA1/2 preset
		// isn't reversed back to preset=PRESET form.
		uint32_t v;
		const void *ptr
			= (const char *)filter_options + optmap[i].offset;
		switch (optmap[i].type) {
			case OPTMAP_TYPE_LZMA_MODE:
				v = *(const lzma_mode *)ptr;
				break;

			case OPTMAP_TYPE_LZMA_MATCH_FINDER:
				v = *(const lzma_match_finder *)ptr;
				break;

			default:
				v = *(const uint32_t *)ptr;
				break;
		}

		// Skip this if this option should be omitted from
		// the string when the value is zero.
		if (v == 0 && (optmap[i].flags & OPTMAP_NO_STRFY_ZERO))
			continue;

		// Before the first option we add whatever delimiter
		// the caller gave us. For later options a comma is used.
		str_append_str(dest, delimiter);
		delimiter = ",";

		// Add the option name and equals sign.
		str_append_str(dest, optmap[i].name);
		str_append_str(dest, "=");

		if (optmap[i].flags & OPTMAP_USE_NAME_VALUE_MAP) {
			const name_value_map *map = optmap[i].u.map;
			size_t j = 0;
			while (true) {
				if (map[j].name[0] == '\0') {
					str_append_str(dest, "UNKNOWN");
					break;
				}

				if (map[j].value == v) {
					str_append_str(dest, map[j].name);
					break;
				}

				++j;
			}
		} else {
			str_append_u32(dest, v,
				optmap[i].flags & OPTMAP_USE_BYTE_SUFFIX);
		}
	}

	return;
}


extern LZMA_API(lzma_ret)
lzma_str_from_filters(char **output_str, const lzma_filter *filters,
		uint32_t flags, const lzma_allocator *allocator)
{
	// On error *output_str is always set to NULL.
	// Do it as the very first step.
	if (output_str == NULL)
		return LZMA_PROG_ERROR;

	*output_str = NULL;

	if (filters == NULL)
		return LZMA_PROG_ERROR;

	// Validate the flags.
	const uint32_t supported_flags
			= LZMA_STR_ENCODER
			| LZMA_STR_DECODER
			| LZMA_STR_GETOPT_LONG
			| LZMA_STR_NO_SPACES;

	if (flags & ~supported_flags)
		return LZMA_OPTIONS_ERROR;

	// There must be at least one filter.
	if (filters[0].id == LZMA_VLI_UNKNOWN)
		return LZMA_OPTIONS_ERROR;

	// Allocate memory for the output string.
	lzma_str dest;
	return_if_error(str_init(&dest, allocator));

	const bool show_opts = (flags & (LZMA_STR_ENCODER | LZMA_STR_DECODER));

	const char *opt_delim = (flags & LZMA_STR_GETOPT_LONG) ? "=" : ":";

	for (size_t i = 0; filters[i].id != LZMA_VLI_UNKNOWN; ++i) {
		// If we reach LZMA_FILTERS_MAX, then the filters array
		// is too large since the ID cannot be LZMA_VLI_UNKNOWN here.
		if (i == LZMA_FILTERS_MAX) {
			str_free(&dest, allocator);
			return LZMA_OPTIONS_ERROR;
		}

		// Don't add a space between filters if the caller
		// doesn't want them.
		if (i > 0 && !(flags & LZMA_STR_NO_SPACES))
			str_append_str(&dest, " ");

		// Use dashes for xz getopt_long() compatible syntax but also
		// use dashes to separate filters when spaces weren't wanted.
		if ((flags & LZMA_STR_GETOPT_LONG)
				|| (i > 0 && (flags & LZMA_STR_NO_SPACES)))
			str_append_str(&dest, "--");

		size_t j = 0;
		while (true) {
			if (j == ARRAY_SIZE(filter_name_map)) {
				// Filter ID in filters[i].id isn't supported.
				str_free(&dest, allocator);
				return LZMA_OPTIONS_ERROR;
			}

			if (filter_name_map[j].id == filters[i].id) {
				// Add the filter name.
				str_append_str(&dest, filter_name_map[j].name);

				// If only the filter names were wanted then
				// skip to the next filter. In this case
				// .options is ignored and may be NULL even
				// when the filter doesn't allow NULL options.
				if (!show_opts)
					break;

				if (filters[i].options == NULL) {
					if (!filter_name_map[j].allow_null) {
						// Filter-specific options
						// are missing but with
						// this filter the options
						// structure is mandatory.
						str_free(&dest, allocator);
						return LZMA_OPTIONS_ERROR;
					}

					// .options is allowed to be NULL.
					// There is no need to add any
					// options to the string.
					break;
				}

				// Options structure is available. Add
				// the filter options to the string.
				const size_t optmap_count
					= (flags & LZMA_STR_ENCODER)
					? filter_name_map[j].strfy_encoder
					: filter_name_map[j].strfy_decoder;
				strfy_filter(&dest, opt_delim,
						filter_name_map[j].optmap,
						optmap_count,
						filters[i].options);
				break;
			}

			++j;
		}
	}

	return str_finish(output_str, &dest, allocator);
}


extern LZMA_API(lzma_ret)
lzma_str_list_filters(char **output_str, lzma_vli filter_id, uint32_t flags,
		const lzma_allocator *allocator)
{
	// On error *output_str is always set to NULL.
	// Do it as the very first step.
	if (output_str == NULL)
		return LZMA_PROG_ERROR;

	*output_str = NULL;

	// Validate the flags.
	const uint32_t supported_flags
			= LZMA_STR_ALL_FILTERS
			| LZMA_STR_ENCODER
			| LZMA_STR_DECODER
			| LZMA_STR_GETOPT_LONG;

	if (flags & ~supported_flags)
		return LZMA_OPTIONS_ERROR;

	// Allocate memory for the output string.
	lzma_str dest;
	return_if_error(str_init(&dest, allocator));

	// If only listing the filter names then separate them with spaces.
	// Otherwise use newlines.
	const bool show_opts = (flags & (LZMA_STR_ENCODER | LZMA_STR_DECODER));
	const char *filter_delim = show_opts ? "\n" : " ";

	const char *opt_delim = (flags & LZMA_STR_GETOPT_LONG) ? "=" : ":";
	bool first_filter_printed = false;

	for (size_t i = 0; i < ARRAY_SIZE(filter_name_map); ++i) {
		// If we are printing only one filter then skip others.
		if (filter_id != LZMA_VLI_UNKNOWN
				&& filter_id != filter_name_map[i].id)
			continue;

		// If we are printing only .xz filters then skip the others.
		if (filter_name_map[i].id >= LZMA_FILTER_RESERVED_START
				&& (flags & LZMA_STR_ALL_FILTERS) == 0
				&& filter_id == LZMA_VLI_UNKNOWN)
			continue;

		// Add a new line if this isn't the first filter being
		// written to the string.
		if (first_filter_printed)
			str_append_str(&dest, filter_delim);

		first_filter_printed = true;

		if (flags & LZMA_STR_GETOPT_LONG)
			str_append_str(&dest, "--");

		str_append_str(&dest, filter_name_map[i].name);

		// If only the filter names were wanted then continue
		// to the next filter.
		if (!show_opts)
			continue;

		const option_map *optmap = filter_name_map[i].optmap;
		const char *d = opt_delim;

		const size_t end = (flags & LZMA_STR_ENCODER)
				? filter_name_map[i].strfy_encoder
				: filter_name_map[i].strfy_decoder;

		for (size_t j = 0; j < end; ++j) {
			// The first option is delimited from the filter
			// name using "=" or ":" and the rest of the options
			// are separated with ",".
			str_append_str(&dest, d);
			d = ",";

			// optname=<possible_values>
			str_append_str(&dest, optmap[j].name);
			str_append_str(&dest, "=<");

			if (optmap[j].type == OPTMAP_TYPE_LZMA_PRESET) {
				// LZMA1/2 preset has its custom help string.
				str_append_str(&dest, LZMA12_PRESET_STR);
			} else if (optmap[j].flags
					& OPTMAP_USE_NAME_VALUE_MAP) {
				// Separate the possible option values by "|".
				const name_value_map *m = optmap[j].u.map;
				for (size_t k = 0; m[k].name[0] != '\0'; ++k) {
					if (k > 0)
						str_append_str(&dest, "|");

					str_append_str(&dest, m[k].name);
				}
			} else {
				// Integer range is shown as min-max.
				const bool use_byte_suffix = optmap[j].flags
						& OPTMAP_USE_BYTE_SUFFIX;
				str_append_u32(&dest, optmap[j].u.range.min,
						use_byte_suffix);
				str_append_str(&dest, "-");
				str_append_u32(&dest, optmap[j].u.range.max,
						use_byte_suffix);
			}

			str_append_str(&dest, ">");
		}
	}

	// If no filters were added to the string then it must be because
	// the caller provided an unsupported Filter ID.
	if (!first_filter_printed) {
		str_free(&dest, allocator);
		return LZMA_OPTIONS_ERROR;
	}

	return str_finish(output_str, &dest, allocator);
}