string_conversion.c

Last change on this file was 98730, checked in by vboxsync, 21 months ago
libs/liblzma-5.4.1: Export to OSE, bugref:10254
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1	///////////////////////////////////////////////////////////////////////////////
2	//
3	/// \file string_conversion.c
4	/// \brief Conversion of strings to filter chain and vice versa
5	//
6	// Author: Lasse Collin
7	//
8	// This file has been put into the public domain.
9	// You can do whatever you want with this file.
10	//
11	///////////////////////////////////////////////////////////////////////////////
12
13	#include "filter_common.h"
14
15
16	/////////////////////
17	// String building //
18	/////////////////////
19
20	/// How much memory to allocate for strings. For now, no realloc is used
21	/// so this needs to be big enough even though there of course is
22	/// an overflow check still.
23	///
24	/// FIXME? Using a fixed size is wasteful if the application doesn't free
25	/// the string fairly quickly but this can be improved later if needed.
26	#define STR_ALLOC_SIZE 800
27
28
29	typedef struct {
30	char *buf;
31	size_t pos;
32	} lzma_str;
33
34
35	static lzma_ret
36	str_init(lzma_str str, const lzma_allocator allocator)
37	{
38	str->buf = lzma_alloc(STR_ALLOC_SIZE, allocator);
39	if (str->buf == NULL)
40	return LZMA_MEM_ERROR;
41
42	str->pos = 0;
43	return LZMA_OK;
44	}
45
46
47	static void
48	str_free(lzma_str str, const lzma_allocator allocator)
49	{
50	lzma_free(str->buf, allocator);
51	return;
52	}
53
54
55	static bool
56	str_is_full(const lzma_str *str)
57	{
58	return str->pos == STR_ALLOC_SIZE - 1;
59	}
60
61
62	static lzma_ret
63	str_finish(char *dest, lzma_str str, const lzma_allocator *allocator)
64	{
65	if (str_is_full(str)) {
66	// The preallocated buffer was too small.
67	// This shouldn't happen as STR_ALLOC_SIZE should
68	// be adjusted if new filters are added.
69	lzma_free(str->buf, allocator);
70	*dest = NULL;
71	assert(0);
72	return LZMA_PROG_ERROR;
73	}
74
75	str->buf[str->pos] = '\0';
76	*dest = str->buf;
77	return LZMA_OK;
78	}
79
80
81	static void
82	str_append_str(lzma_str str, const char s)
83	{
84	const size_t len = strlen(s);
85	const size_t limit = STR_ALLOC_SIZE - 1 - str->pos;
86	const size_t copy_size = my_min(len, limit);
87
88	memcpy(str->buf + str->pos, s, copy_size);
89	str->pos += copy_size;
90	return;
91	}
92
93
94	static void
95	str_append_u32(lzma_str *str, uint32_t v, bool use_byte_suffix)
96	{
97	if (v == 0) {
98	str_append_str(str, "0");
99	} else {
100	// NOTE: Don't use plain "B" because xz and the parser in this
101	// file don't support it and at glance it may look like 8
102	// (there cannot be a space before the suffix).
103	static const char suffixes[4][4] = { "", "KiB", "MiB", "GiB" };
104
105	size_t suf = 0;
106	if (use_byte_suffix) {
107	while ((v & 1023) == 0
108	&& suf < ARRAY_SIZE(suffixes) - 1) {
109	v >>= 10;
110	++suf;
111	}
112	}
113
114	// UINT32_MAX in base 10 would need 10 + 1 bytes. Remember
115	// that initializing to "" initializes all elements to
116	// zero so '\0'-termination gets handled by this.
117	char buf[16] = "";
118	size_t pos = sizeof(buf) - 1;
119
120	do {
121	buf[--pos] = '0' + (v % 10);
122	v /= 10;
123	} while (v != 0);
124
125	str_append_str(str, buf + pos);
126	str_append_str(str, suffixes[suf]);
127	}
128
129	return;
130	}
131
132
133	//////////////////////////////////////////////
134	// Parsing and stringification declarations //
135	//////////////////////////////////////////////
136
137	/// Maximum length for filter and option names.
138	/// 11 chars + terminating '\0' + sizeof(uint32_t) = 16 bytes
139	#define NAME_LEN_MAX 11
140
141
142	/// For option_map.flags: Use .u.map to do convert the input value
143	/// to an integer. Without this flag, .u.range.{min,max} are used
144	/// as the allowed range for the integer.
145	#define OPTMAP_USE_NAME_VALUE_MAP 0x01
146
147	/// For option_map.flags: Allow KiB/MiB/GiB in input string and use them in
148	/// the stringified output if the value is an exact multiple of these.
149	/// This is used e.g. for LZMA1/2 dictionary size.
150	#define OPTMAP_USE_BYTE_SUFFIX 0x02
151
152	/// For option_map.flags: If the integer value is zero then this option
153	/// won't be included in the stringified output. It's used e.g. for
154	/// BCJ filter start offset which usually is zero.
155	#define OPTMAP_NO_STRFY_ZERO 0x04
156
157	/// Possible values for option_map.type. Since OPTMAP_TYPE_UINT32 is 0,
158	/// it doesn't need to be specified in the initializers as it is
159	/// the implicit value.
160	enum {
161	OPTMAP_TYPE_UINT32,
162	OPTMAP_TYPE_LZMA_MODE,
163	OPTMAP_TYPE_LZMA_MATCH_FINDER,
164	OPTMAP_TYPE_LZMA_PRESET,
165	};
166
167
168	/// This is for mapping string values in options to integers.
169	/// The last element of an array must have "" as the name.
170	/// It's used e.g. for match finder names in LZMA1/2.
171	typedef struct {
172	const char name[NAME_LEN_MAX + 1];
173	const uint32_t value;
174	} name_value_map;
175
176
177	/// Each filter that has options needs an array of option_map structures.
178	/// The array doesn't need to be terminated as the functions take the
179	/// length of the array as an argument.
180	///
181	/// When converting a string to filter options structure, option values
182	/// will be handled in a few different ways:
183	///
184	/// (1) If .type equals OPTMAP_TYPE_LZMA_PRESET then LZMA1/2 preset string
185	/// is handled specially.
186	///
187	/// (2) If .flags has OPTMAP_USE_NAME_VALUE_MAP set then the string is
188	/// converted to an integer using the name_value_map pointed by .u.map.
189	/// The last element in .u.map must have .name = "" as the terminator.
190	///
191	/// (3) Otherwise the string is treated as a non-negative unsigned decimal
192	/// integer which must be in the range set in .u.range. If .flags has
193	/// OPTMAP_USE_BYTE_SUFFIX then KiB, MiB, and GiB suffixes are allowed.
194	///
195	/// The integer value from (2) or (3) is then stored to filter_options
196	/// at the offset specified in .offset using the type specified in .type
197	/// (default is uint32_t).
198	///
199	/// Stringifying a filter is done by processing a given number of options
200	/// in oder from the beginning of an option_map array. The integer is
201	/// read from filter_options at .offset using the type from .type.
202	///
203	/// If the integer is zero and .flags has OPTMAP_NO_STRFY_ZERO then the
204	/// option is skipped.
205	///
206	/// If .flags has OPTMAP_USE_NAME_VALUE_MAP set then .u.map will be used
207	/// to convert the option to a string. If the map doesn't contain a string
208	/// for the integer value then "UNKNOWN" is used.
209	///
210	/// If .flags doesn't have OPTMAP_USE_NAME_VALUE_MAP set then the integer is
211	/// converted to a decimal value. If OPTMAP_USE_BYTE_SUFFIX is used then KiB,
212	/// MiB, or GiB suffix is used if the value is an exact multiple of these.
213	/// Plain "B" suffix is never used.
214	typedef struct {
215	char name[NAME_LEN_MAX + 1];
216	uint8_t type;
217	uint8_t flags;
218	uint16_t offset;
219
220	union {
221	struct {
222	uint32_t min;
223	uint32_t max;
224	} range;
225
226	const name_value_map *map;
227	} u;
228	} option_map;
229
230
231	static const char parse_options(const char const str, const char str_end,
232	void *filter_options,
233	const option_map *const optmap, const size_t optmap_size);
234
235
236	/////////
237	// BCJ //
238	/////////
239
240	#if defined(HAVE_ENCODER_X86) \
241	\|\| defined(HAVE_DECODER_X86) \
242	\|\| defined(HAVE_ENCODER_ARM) \
243	\|\| defined(HAVE_DECODER_ARM) \
244	\|\| defined(HAVE_ENCODER_ARMTHUMB) \
245	\|\| defined(HAVE_DECODER_ARMTHUMB) \
246	\|\| defined(HAVE_ENCODER_ARM64) \
247	\|\| defined(HAVE_DECODER_ARM64) \
248	\|\| defined(HAVE_ENCODER_POWERPC) \
249	\|\| defined(HAVE_DECODER_POWERPC) \
250	\|\| defined(HAVE_ENCODER_IA64) \
251	\|\| defined(HAVE_DECODER_IA64) \
252	\|\| defined(HAVE_ENCODER_SPARC) \
253	\|\| defined(HAVE_DECODER_SPARC)
254	static const option_map bcj_optmap[] = {
255	{
256	.name = "start",
257	.flags = OPTMAP_NO_STRFY_ZERO \| OPTMAP_USE_BYTE_SUFFIX,
258	.offset = offsetof(lzma_options_bcj, start_offset),
259	.u.range.min = 0,
260	.u.range.max = UINT32_MAX,
261	}
262	};
263
264
265	static const char *
266	parse_bcj(const char *const str, const char str_end, void *filter_options)
267	{
268	// filter_options was zeroed on allocation and that is enough
269	// for the default value.
270	return parse_options(str, str_end, filter_options,
271	bcj_optmap, ARRAY_SIZE(bcj_optmap));
272	}
273	#endif
274
275
276	///////////
277	// Delta //
278	///////////
279
280	#if defined(HAVE_ENCODER_DELTA) \|\| defined(HAVE_DECODER_DELTA)
281	static const option_map delta_optmap[] = {
282	{
283	.name = "dist",
284	.offset = offsetof(lzma_options_delta, dist),
285	.u.range.min = LZMA_DELTA_DIST_MIN,
286	.u.range.max = LZMA_DELTA_DIST_MAX,
287	}
288	};
289
290
291	static const char *
292	parse_delta(const char *const str, const char str_end, void *filter_options)
293	{
294	lzma_options_delta *opts = filter_options;
295	opts->type = LZMA_DELTA_TYPE_BYTE;
296	opts->dist = LZMA_DELTA_DIST_MIN;
297
298	return parse_options(str, str_end, filter_options,
299	delta_optmap, ARRAY_SIZE(delta_optmap));
300	}
301	#endif
302
303
304	///////////////////
305	// LZMA1 & LZMA2 //
306	///////////////////
307
308	/// Help string for presets
309	#define LZMA12_PRESET_STR "0-9[e]"
310
311
312	static const char *
313	parse_lzma12_preset(const char *const str, const char str_end,
314	uint32_t *preset)
315	{
316	assert(*str < str_end);
317	preset = (uint32_t)(*str - '0');
318
319	// NOTE: Remember to update LZMA_PRESET_STR if this is modified!
320	while (++*str < str_end) {
321	switch (**str) {
322	case 'e':
323	*preset \|= LZMA_PRESET_EXTREME;
324	break;
325
326	default:
327	return "Unsupported preset flag";
328	}
329	}
330
331	return NULL;
332	}
333
334
335	static const char *
336	set_lzma12_preset(const char *const str, const char str_end,
337	void *filter_options)
338	{
339	uint32_t preset;
340	const char *errmsg = parse_lzma12_preset(str, str_end, &preset);
341	if (errmsg != NULL)
342	return errmsg;
343
344	lzma_options_lzma *opts = filter_options;
345	if (lzma_lzma_preset(opts, preset))
346	return "Unsupported preset";
347
348	return NULL;
349	}
350
351
352	static const name_value_map lzma12_mode_map[] = {
353	{ "fast", LZMA_MODE_FAST },
354	{ "normal", LZMA_MODE_NORMAL },
355	{ "", 0 }
356	};
357
358
359	static const name_value_map lzma12_mf_map[] = {
360	{ "hc3", LZMA_MF_HC3 },
361	{ "hc4", LZMA_MF_HC4 },
362	{ "bt2", LZMA_MF_BT2 },
363	{ "bt3", LZMA_MF_BT3 },
364	{ "bt4", LZMA_MF_BT4 },
365	{ "", 0 }
366	};
367
368
369	static const option_map lzma12_optmap[] = {
370	{
371	.name = "preset",
372	.type = OPTMAP_TYPE_LZMA_PRESET,
373	}, {
374	.name = "dict",
375	.flags = OPTMAP_USE_BYTE_SUFFIX,
376	.offset = offsetof(lzma_options_lzma, dict_size),
377	.u.range.min = LZMA_DICT_SIZE_MIN,
378	// FIXME? The max is really max for encoding but decoding
379	// would allow 4 GiB - 1 B.
380	.u.range.max = (UINT32_C(1) << 30) + (UINT32_C(1) << 29),
381	}, {
382	.name = "lc",
383	.offset = offsetof(lzma_options_lzma, lc),
384	.u.range.min = LZMA_LCLP_MIN,
385	.u.range.max = LZMA_LCLP_MAX,
386	}, {
387	.name = "lp",
388	.offset = offsetof(lzma_options_lzma, lp),
389	.u.range.min = LZMA_LCLP_MIN,
390	.u.range.max = LZMA_LCLP_MAX,
391	}, {
392	.name = "pb",
393	.offset = offsetof(lzma_options_lzma, pb),
394	.u.range.min = LZMA_PB_MIN,
395	.u.range.max = LZMA_PB_MAX,
396	}, {
397	.name = "mode",
398	.type = OPTMAP_TYPE_LZMA_MODE,
399	.flags = OPTMAP_USE_NAME_VALUE_MAP,
400	.offset = offsetof(lzma_options_lzma, mode),
401	.u.map = lzma12_mode_map,
402	}, {
403	.name = "nice",
404	.offset = offsetof(lzma_options_lzma, nice_len),
405	.u.range.min = 2,
406	.u.range.max = 273,
407	}, {
408	.name = "mf",
409	.type = OPTMAP_TYPE_LZMA_MATCH_FINDER,
410	.flags = OPTMAP_USE_NAME_VALUE_MAP,
411	.offset = offsetof(lzma_options_lzma, mf),
412	.u.map = lzma12_mf_map,
413	}, {
414	.name = "depth",
415	.offset = offsetof(lzma_options_lzma, depth),
416	.u.range.min = 0,
417	.u.range.max = UINT32_MAX,
418	}
419	};
420
421
422	static const char *
423	parse_lzma12(const char *const str, const char str_end, void *filter_options)
424	{
425	lzma_options_lzma *opts = filter_options;
426
427	// It cannot fail.
428	const bool preset_ret = lzma_lzma_preset(opts, LZMA_PRESET_DEFAULT);
429	assert(!preset_ret);
430	(void)preset_ret;
431
432	const char *errmsg = parse_options(str, str_end, filter_options,
433	lzma12_optmap, ARRAY_SIZE(lzma12_optmap));
434	if (errmsg != NULL)
435	return errmsg;
436
437	if (opts->lc + opts->lp > LZMA_LCLP_MAX)
438	return "The sum of lc and lp must not exceed 4";
439
440	return NULL;
441	}
442
443
444	/////////////////////////////////////////
445	// Generic parsing and stringification //
446	/////////////////////////////////////////
447
448	static const struct {
449	/// Name of the filter
450	char name[NAME_LEN_MAX + 1];
451
452	/// For lzma_str_to_filters:
453	/// Size of the filter-specific options structure.
454	uint32_t opts_size;
455
456	/// Filter ID
457	lzma_vli id;
458
459	/// For lzma_str_to_filters:
460	/// Function to parse the filter-specific options. The filter_options
461	/// will already have been allocated using lzma_alloc_zero().
462	const char (parse)(const char *str, const char str_end,
463	void *filter_options);
464
465	/// For lzma_str_from_filters:
466	/// If the flag LZMA_STR_ENCODER is used then the first
467	/// strfy_encoder elements of optmap are stringified.
468	/// With LZMA_STR_DECODER strfy_decoder is used.
469	/// Currently encoders use all flags that decoders do but if
470	/// that changes then this needs to be changed too, for example,
471	/// add a new OPTMAP flag to skip printing some decoder-only flags.
472	const option_map *optmap;
473	uint8_t strfy_encoder;
474	uint8_t strfy_decoder;
475
476	/// For lzma_str_from_filters:
477	/// If true, lzma_filter.options is allowed to be NULL. In that case,
478	/// only the filter name is printed without any options.
479	bool allow_null;
480
481	} filter_name_map[] = {
482	#if defined (HAVE_ENCODER_LZMA1) \|\| defined(HAVE_DECODER_LZMA1)
483	{ "lzma1", sizeof(lzma_options_lzma), LZMA_FILTER_LZMA1,
484	&parse_lzma12, lzma12_optmap, 9, 5, false },
485	#endif
486
487	#if defined(HAVE_ENCODER_LZMA2) \|\| defined(HAVE_DECODER_LZMA2)
488	{ "lzma2", sizeof(lzma_options_lzma), LZMA_FILTER_LZMA2,
489	&parse_lzma12, lzma12_optmap, 9, 2, false },
490	#endif
491
492	#if defined(HAVE_ENCODER_X86) \|\| defined(HAVE_DECODER_X86)
493	{ "x86", sizeof(lzma_options_bcj), LZMA_FILTER_X86,
494	&parse_bcj, bcj_optmap, 1, 1, true },
495	#endif
496
497	#if defined(HAVE_ENCODER_ARM) \|\| defined(HAVE_DECODER_ARM)
498	{ "arm", sizeof(lzma_options_bcj), LZMA_FILTER_ARM,
499	&parse_bcj, bcj_optmap, 1, 1, true },
500	#endif
501
502	#if defined(HAVE_ENCODER_ARMTHUMB) \|\| defined(HAVE_DECODER_ARMTHUMB)
503	{ "armthumb", sizeof(lzma_options_bcj), LZMA_FILTER_ARMTHUMB,
504	&parse_bcj, bcj_optmap, 1, 1, true },
505	#endif
506
507	#if defined(HAVE_ENCODER_ARM64) \|\| defined(HAVE_DECODER_ARM64)
508	{ "arm64", sizeof(lzma_options_bcj), LZMA_FILTER_ARM64,
509	&parse_bcj, bcj_optmap, 1, 1, true },
510	#endif
511
512	#if defined(HAVE_ENCODER_POWERPC) \|\| defined(HAVE_DECODER_POWERPC)
513	{ "powerpc", sizeof(lzma_options_bcj), LZMA_FILTER_POWERPC,
514	&parse_bcj, bcj_optmap, 1, 1, true },
515	#endif
516
517	#if defined(HAVE_ENCODER_IA64) \|\| defined(HAVE_DECODER_IA64)
518	{ "ia64", sizeof(lzma_options_bcj), LZMA_FILTER_IA64,
519	&parse_bcj, bcj_optmap, 1, 1, true },
520	#endif
521
522	#if defined(HAVE_ENCODER_SPARC) \|\| defined(HAVE_DECODER_SPARC)
523	{ "sparc", sizeof(lzma_options_bcj), LZMA_FILTER_SPARC,
524	&parse_bcj, bcj_optmap, 1, 1, true },
525	#endif
526
527	#if defined(HAVE_ENCODER_DELTA) \|\| defined(HAVE_DECODER_DELTA)
528	{ "delta", sizeof(lzma_options_delta), LZMA_FILTER_DELTA,
529	&parse_delta, delta_optmap, 1, 1, false },
530	#endif
531	};
532
533
534	/// Decodes options from a string for one filter (name1=value1,name2=value2).
535	/// Caller must have allocated memory for filter_options already and set
536	/// the initial default values. This is called from the filter-specific
537	/// parse_* functions.
538	///
539	/// The input string starts at *str and the address in str_end is the first
540	/// char that is not part of the string anymore. So no '\0' terminator is
541	/// used. *str is advanced everytime something has been decoded successfully.
542	static const char *
543	parse_options(const char *const str, const char str_end,
544	void *filter_options,
545	const option_map *const optmap, const size_t optmap_size)
546	{
547	while (str < str_end && *str != '\0') {
548	// Each option is of the form name=value.
549	// Commas (',') separate options. Extra commas are ignored.
550	// Ignoring extra commas makes it simpler if an optional
551	// option stored in a shell variable which can be empty.
552	if (**str == ',') {
553	++*str;
554	continue;
555	}
556
557	// Find where the next name=value ends.
558	const size_t str_len = (size_t)(str_end - *str);
559	const char name_eq_value_end = memchr(str, ',', str_len);
560	if (name_eq_value_end == NULL)
561	name_eq_value_end = str_end;
562
563	const char equals_sign = memchr(str, '=',
564	(size_t)(name_eq_value_end - *str));
565
566	// Fail if the '=' wasn't found or the option name is missing
567	// (the first char is '=').
568	if (equals_sign == NULL \|\| **str == '=')
569	return "Options must be 'name=value' pairs separated "
570	"with commas";
571
572	// Reject a too long option name so that the memcmp()
573	// in the loop below won't read past the end of the
574	// string in optmap[i].name.
575	const size_t name_len = (size_t)(equals_sign - *str);
576	if (name_len > NAME_LEN_MAX)
577	return "Unknown option name";
578
579	// Find the option name from optmap[].
580	size_t i = 0;
581	while (true) {
582	if (i == optmap_size)
583	return "Unknown option name";
584
585	if (memcmp(*str, optmap[i].name, name_len) == 0
586	&& optmap[i].name[name_len] == '\0')
587	break;
588
589	++i;
590	}
591
592	// The input string is good at least until the start of
593	// the option value.
594	*str = equals_sign + 1;
595
596	// The code assumes that the option value isn't an empty
597	// string so check it here.
598	const size_t value_len = (size_t)(name_eq_value_end - *str);
599	if (value_len == 0)
600	return "Option value cannot be empty";
601
602	// LZMA1/2 preset has its own parsing function.
603	if (optmap[i].type == OPTMAP_TYPE_LZMA_PRESET) {
604	const char *errmsg = set_lzma12_preset(str,
605	name_eq_value_end, filter_options);
606	if (errmsg != NULL)
607	return errmsg;
608
609	continue;
610	}
611
612	// It's an integer value.
613	uint32_t v;
614	if (optmap[i].flags & OPTMAP_USE_NAME_VALUE_MAP) {
615	// The integer is picked from a string-to-integer map.
616	//
617	// Reject a too long value string so that the memcmp()
618	// in the loop below won't read past the end of the
619	// string in optmap[i].u.map[j].name.
620	if (value_len > NAME_LEN_MAX)
621	return "Invalid option value";
622
623	const name_value_map *map = optmap[i].u.map;
624	size_t j = 0;
625	while (true) {
626	// The array is terminated with an empty name.
627	if (map[j].name[0] == '\0')
628	return "Invalid option value";
629
630	if (memcmp(*str, map[j].name, value_len) == 0
631	&& map[j].name[value_len]
632	== '\0') {
633	v = map[j].value;
634	break;
635	}
636
637	++j;
638	}
639	} else if (str < '0' \|\| str > '9') {
640	// Note that "max" isn't supported while it is
641	// supported in xz. It's not useful here.
642	return "Value is not a non-negative decimal integer";
643	} else {
644	// strtoul() has locale-specific behavior so it cannot
645	// be relied on to get reproducible results since we
646	// cannot change the locate in a thread-safe library.
647	// It also needs '\0'-termination.
648	//
649	// Use a temporary pointer so that *str will point
650	// to the beginning of the value string in case
651	// an error occurs.
652	const char p = str;
653	v = 0;
654	do {
655	if (v > UINT32_MAX / 10)
656	return "Value out of range";
657
658	v *= 10;
659
660	const uint32_t add = (uint32_t)(*p - '0');
661	if (UINT32_MAX - add < v)
662	return "Value out of range";
663
664	v += add;
665	++p;
666	} while (p < name_eq_value_end
667	&& p >= '0' && p <= '9');
668
669	if (p < name_eq_value_end) {
670	// Remember this position so that it an be
671	// used for error messages that are
672	// specifically about the suffix. (Out of
673	// range values are about the whole value
674	// and those error messages point to the
675	// beginning of the number part,
676	// not to the suffix.)
677	const char *multiplier_start = p;
678
679	// If multiplier suffix shouldn't be used
680	// then don't allow them even if the value
681	// would stay within limits. This is a somewhat
682	// unnecessary check but it rejects silly
683	// things like lzma2:pb=0MiB which xz allows.
684	if ((optmap[i].flags & OPTMAP_USE_BYTE_SUFFIX)
685	== 0) {
686	*str = multiplier_start;
687	return "This option does not support "
688	"any integer suffixes";
689	}
690
691	uint32_t shift;
692
693	switch (*p) {
694	case 'k':
695	case 'K':
696	shift = 10;
697	break;
698
699	case 'm':
700	case 'M':
701	shift = 20;
702	break;
703
704	case 'g':
705	case 'G':
706	shift = 30;
707	break;
708
709	default:
710	*str = multiplier_start;
711	return "Invalid multiplier suffix "
712	"(KiB, MiB, or GiB)";
713	}
714
715	++p;
716
717	// Allow "M", "Mi", "MB", "MiB" and the same
718	// for the other five characters from the
719	// switch-statement above. All are handled
720	// as base-2 (perhaps a mistake, perhaps not).
721	// Note that 'i' and 'B' are case sensitive.
722	if (p < name_eq_value_end && *p == 'i')
723	++p;
724
725	if (p < name_eq_value_end && *p == 'B')
726	++p;
727
728	// Now we must have no chars remaining.
729	if (p < name_eq_value_end) {
730	*str = multiplier_start;
731	return "Invalid multiplier suffix "
732	"(KiB, MiB, or GiB)";
733	}
734
735	if (v > (UINT32_MAX >> shift))
736	return "Value out of range";
737
738	v <<= shift;
739	}
740
741	if (v < optmap[i].u.range.min
742	\|\| v > optmap[i].u.range.max)
743	return "Value out of range";
744	}
745
746	// Set the value in filter_options. Enums are handled
747	// specially since the underlying type isn't the same
748	// as uint32_t on all systems.
749	void ptr = (char )filter_options + optmap[i].offset;
750	switch (optmap[i].type) {
751	case OPTMAP_TYPE_LZMA_MODE:
752	(lzma_mode )ptr = (lzma_mode)v;
753	break;
754
755	case OPTMAP_TYPE_LZMA_MATCH_FINDER:
756	(lzma_match_finder )ptr = (lzma_match_finder)v;
757	break;
758
759	default:
760	(uint32_t )ptr = v;
761	break;
762	}
763
764	// This option has been successfully handled.
765	*str = name_eq_value_end;
766	}
767
768	// No errors.
769	return NULL;
770	}
771
772
773	/// Finds the name of the filter at the beginning of the string and
774	/// calls filter_name_map[i].parse() to decode the filter-specific options.
775	/// The caller must have set str_end so that exactly one filter and its
776	/// options are present without any trailing characters.
777	static const char *
778	parse_filter(const char *const str, const char str_end, lzma_filter *filter,
779	const lzma_allocator *allocator, bool only_xz)
780	{
781	// Search for a colon or equals sign that would separate the filter
782	// name from filter options. If neither is found, then the input
783	// string only contains a filter name and there are no options.
784	//
785	// First assume that a colon or equals sign won't be found:
786	const char *name_end = str_end;
787	const char *opts_start = str_end;
788
789	for (const char p = str; p < str_end; ++p) {
790	if (p == ':' \|\| p == '=') {
791	name_end = p;
792
793	// Filter options (name1=value1,name2=value2,...)
794	// begin after the colon or equals sign.
795	opts_start = p + 1;
796	break;
797	}
798	}
799
800	// Reject a too long filter name so that the memcmp()
801	// in the loop below won't read past the end of the
802	// string in filter_name_map[i].name.
803	const size_t name_len = (size_t)(name_end - *str);
804	if (name_len > NAME_LEN_MAX)
805	return "Unknown filter name";
806
807	for (size_t i = 0; i < ARRAY_SIZE(filter_name_map); ++i) {
808	if (memcmp(*str, filter_name_map[i].name, name_len) == 0
809	&& filter_name_map[i].name[name_len] == '\0') {
810	if (only_xz && filter_name_map[i].id
811	>= LZMA_FILTER_RESERVED_START)
812	return "This filter cannot be used in "
813	"the .xz format";
814
815	// Allocate the filter-specific options and
816	// initialize the memory with zeros.
817	void *options = lzma_alloc_zero(
818	filter_name_map[i].opts_size,
819	allocator);
820	if (options == NULL)
821	return "Memory allocation failed";
822
823	// Filter name was found so the input string is good
824	// at least this far.
825	*str = opts_start;
826
827	const char *errmsg = filter_name_map[i].parse(
828	str, str_end, options);
829	if (errmsg != NULL) {
830	lzma_free(options, allocator);
831	return errmsg;
832	}
833
834	// *filter is modified only when parsing is successful.
835	filter->id = filter_name_map[i].id;
836	filter->options = options;
837	return NULL;
838	}
839	}
840
841	return "Unknown filter name";
842	}
843
844
845	/// Converts the string to a filter chain (array of lzma_filter structures).
846	///
847	/// *str is advanced everytime something has been decoded successfully.
848	/// This way the caller knows where in the string a possible error occurred.
849	static const char *
850	str_to_filters(const char *const str, lzma_filter filters, uint32_t flags,
851	const lzma_allocator *allocator)
852	{
853	const char *errmsg;
854
855	// Skip leading spaces.
856	while (**str == ' ')
857	++*str;
858
859	if (**str == '\0')
860	return "Empty string is not allowed, "
861	"try \"6\" if a default value is needed";
862
863	// Detect the type of the string.
864	//
865	// A string beginning with a digit or a string beginning with
866	// one dash and a digit are treated as presets. Trailing spaces
867	// will be ignored too (leading spaces were already ignored above).
868	//
869	// For example, "6", "7 ", "-9e", or " -3 " are treated as presets.
870	// Strings like "-" or "- " aren't preset.
871	#define MY_IS_DIGIT(c) ((c) >= '0' && (c) <= '9')
872	if (MY_IS_DIGIT(str) \|\| (str == '-' && MY_IS_DIGIT((*str)[1]))) {
873	if (**str == '-')
874	++*str;
875
876	// Ignore trailing spaces.
877	const size_t str_len = strlen(*str);
878	const char str_end = memchr(str, ' ', str_len);
879	if (str_end != NULL) {
880	// There is at least one trailing space. Check that
881	// there are no chars other than spaces.
882	for (size_t i = 1; str_end[i] != '\0'; ++i)
883	if (str_end[i] != ' ')
884	return "Unsupported preset";
885	} else {
886	// There are no trailing spaces. Use the whole string.
887	str_end = *str + str_len;
888	}
889
890	uint32_t preset;
891	errmsg = parse_lzma12_preset(str, str_end, &preset);
892	if (errmsg != NULL)
893	return errmsg;
894
895	lzma_options_lzma opts = lzma_alloc(sizeof(opts), allocator);
896	if (opts == NULL)
897	return "Memory allocation failed";
898
899	if (lzma_lzma_preset(opts, preset)) {
900	lzma_free(opts, allocator);
901	return "Unsupported preset";
902	}
903
904	filters[0].id = LZMA_FILTER_LZMA2;
905	filters[0].options = opts;
906	filters[1].id = LZMA_VLI_UNKNOWN;
907	filters[1].options = NULL;
908
909	return NULL;
910	}
911
912	// Not a preset so it must be a filter chain.
913	//
914	// If LZMA_STR_ALL_FILTERS isn't used we allow only filters that
915	// can be used in .xz.
916	const bool only_xz = (flags & LZMA_STR_ALL_FILTERS) == 0;
917
918	// Use a temporary array so that we don't modify the caller-supplied
919	// one until we know that no errors occurred.
920	lzma_filter temp_filters[LZMA_FILTERS_MAX + 1];
921
922	size_t i = 0;
923	do {
924	if (i == LZMA_FILTERS_MAX) {
925	errmsg = "The maximum number of filters is four";
926	goto error;
927	}
928
929	// Skip "--" if present.
930	if ((str)[0] == '-' && (str)[1] == '-')
931	*str += 2;
932
933	// Locate the end of "filter:name1=value1,name2=value2",
934	// stopping at the first "--" or a single space.
935	const char filter_end = str;
936	while (filter_end[0] != '\0') {
937	if ((filter_end[0] == '-' && filter_end[1] == '-')
938	\|\| filter_end[0] == ' ')
939	break;
940
941	++filter_end;
942	}
943
944	// Inputs that have "--" at the end or "-- " in the middle
945	// will result in an empty filter name.
946	if (filter_end == *str) {
947	errmsg = "Filter name is missing";
948	goto error;
949	}
950
951	errmsg = parse_filter(str, filter_end, &temp_filters[i],
952	allocator, only_xz);
953	if (errmsg != NULL)
954	goto error;
955
956	// Skip trailing spaces.
957	while (**str == ' ')
958	++*str;
959
960	++i;
961	} while (**str != '\0');
962
963	// Seems to be good, terminate the array so that
964	// basic validation can be done.
965	temp_filters[i].id = LZMA_VLI_UNKNOWN;
966	temp_filters[i].options = NULL;
967
968	// Do basic validation if the application didn't prohibit it.
969	if ((flags & LZMA_STR_NO_VALIDATION) == 0) {
970	size_t dummy;
971	const lzma_ret ret = lzma_validate_chain(temp_filters, &dummy);
972	assert(ret == LZMA_OK \|\| ret == LZMA_OPTIONS_ERROR);
973	if (ret != LZMA_OK) {
974	errmsg = "Invalid filter chain "
975	"('lzma2' missing at the end?)";
976	goto error;
977	}
978	}
979
980	// All good. Copy the filters to the application supplied array.
981	memcpy(filters, temp_filters, (i + 1) * sizeof(lzma_filter));
982	return NULL;
983
984	error:
985	// Free the filter options that were successfully decoded.
986	while (i-- > 0)
987	lzma_free(temp_filters[i].options, allocator);
988
989	return errmsg;
990	}
991
992
993	extern LZMA_API(const char *)
994	lzma_str_to_filters(const char str, int error_pos, lzma_filter *filters,
995	uint32_t flags, const lzma_allocator *allocator)
996	{
997	if (str == NULL \|\| filters == NULL)
998	return "Unexpected NULL pointer argument(s) "
999	"to lzma_str_to_filters()";
1000
1001	// Validate the flags.
1002	const uint32_t supported_flags
1003	= LZMA_STR_ALL_FILTERS
1004	\| LZMA_STR_NO_VALIDATION;
1005
1006	if (flags & ~supported_flags)
1007	return "Unsupported flags to lzma_str_to_filters()";
1008
1009	const char *used = str;
1010	const char *errmsg = str_to_filters(&used, filters, flags, allocator);
1011
1012	if (error_pos != NULL) {
1013	const size_t n = (size_t)(used - str);
1014	*error_pos = n > INT_MAX ? INT_MAX : (int)n;
1015	}
1016
1017	return errmsg;
1018	}
1019
1020
1021	/// Converts options of one filter to a string.
1022	///
1023	/// The caller must have already put the filter name in the destination
1024	/// string. Since it is possible that no options will be needed, the caller
1025	/// won't have put a delimiter character (':' or '=') in the string yet.
1026	/// We will add it if at least one option will be added to the string.
1027	static void
1028	strfy_filter(lzma_str dest, const char delimiter,
1029	const option_map *optmap, size_t optmap_count,
1030	const void *filter_options)
1031	{
1032	for (size_t i = 0; i < optmap_count; ++i) {
1033	// No attempt is made to reverse LZMA1/2 preset.
1034	if (optmap[i].type == OPTMAP_TYPE_LZMA_PRESET)
1035	continue;
1036
1037	// All options have integer values, some just are mapped
1038	// to a string with a name_value_map. LZMA1/2 preset
1039	// isn't reversed back to preset=PRESET form.
1040	uint32_t v;
1041	const void *ptr
1042	= (const char *)filter_options + optmap[i].offset;
1043	switch (optmap[i].type) {
1044	case OPTMAP_TYPE_LZMA_MODE:
1045	v = (const lzma_mode )ptr;
1046	break;
1047
1048	case OPTMAP_TYPE_LZMA_MATCH_FINDER:
1049	v = (const lzma_match_finder )ptr;
1050	break;
1051
1052	default:
1053	v = (const uint32_t )ptr;
1054	break;
1055	}
1056
1057	// Skip this if this option should be omitted from
1058	// the string when the value is zero.
1059	if (v == 0 && (optmap[i].flags & OPTMAP_NO_STRFY_ZERO))
1060	continue;
1061
1062	// Before the first option we add whatever delimiter
1063	// the caller gave us. For later options a comma is used.
1064	str_append_str(dest, delimiter);
1065	delimiter = ",";
1066
1067	// Add the option name and equals sign.
1068	str_append_str(dest, optmap[i].name);
1069	str_append_str(dest, "=");
1070
1071	if (optmap[i].flags & OPTMAP_USE_NAME_VALUE_MAP) {
1072	const name_value_map *map = optmap[i].u.map;
1073	size_t j = 0;
1074	while (true) {
1075	if (map[j].name[0] == '\0') {
1076	str_append_str(dest, "UNKNOWN");
1077	break;
1078	}
1079
1080	if (map[j].value == v) {
1081	str_append_str(dest, map[j].name);
1082	break;
1083	}
1084
1085	++j;
1086	}
1087	} else {
1088	str_append_u32(dest, v,
1089	optmap[i].flags & OPTMAP_USE_BYTE_SUFFIX);
1090	}
1091	}
1092
1093	return;
1094	}
1095
1096
1097	extern LZMA_API(lzma_ret)
1098	lzma_str_from_filters(char *output_str, const lzma_filter filters,
1099	uint32_t flags, const lzma_allocator *allocator)
1100	{
1101	// On error *output_str is always set to NULL.
1102	// Do it as the very first step.
1103	if (output_str == NULL)
1104	return LZMA_PROG_ERROR;
1105
1106	*output_str = NULL;
1107
1108	if (filters == NULL)
1109	return LZMA_PROG_ERROR;
1110
1111	// Validate the flags.
1112	const uint32_t supported_flags
1113	= LZMA_STR_ENCODER
1114	\| LZMA_STR_DECODER
1115	\| LZMA_STR_GETOPT_LONG
1116	\| LZMA_STR_NO_SPACES;
1117
1118	if (flags & ~supported_flags)
1119	return LZMA_OPTIONS_ERROR;
1120
1121	// There must be at least one filter.
1122	if (filters[0].id == LZMA_VLI_UNKNOWN)
1123	return LZMA_OPTIONS_ERROR;
1124
1125	// Allocate memory for the output string.
1126	lzma_str dest;
1127	return_if_error(str_init(&dest, allocator));
1128
1129	const bool show_opts = (flags & (LZMA_STR_ENCODER \| LZMA_STR_DECODER));
1130
1131	const char *opt_delim = (flags & LZMA_STR_GETOPT_LONG) ? "=" : ":";
1132
1133	for (size_t i = 0; filters[i].id != LZMA_VLI_UNKNOWN; ++i) {
1134	// Don't add a space between filters if the caller
1135	// doesn't want them.
1136	if (i > 0 && !(flags & LZMA_STR_NO_SPACES))
1137	str_append_str(&dest, " ");
1138
1139	// Use dashes for xz getopt_long() compatible syntax but also
1140	// use dashes to separate filters when spaces weren't wanted.
1141	if ((flags & LZMA_STR_GETOPT_LONG)
1142	\|\| (i > 0 && (flags & LZMA_STR_NO_SPACES)))
1143	str_append_str(&dest, "--");
1144
1145	size_t j = 0;
1146	while (true) {
1147	if (j == ARRAY_SIZE(filter_name_map)) {
1148	// Filter ID in filters[i].id isn't supported.
1149	str_free(&dest, allocator);
1150	return LZMA_OPTIONS_ERROR;
1151	}
1152
1153	if (filter_name_map[j].id == filters[i].id) {
1154	// Add the filter name.
1155	str_append_str(&dest, filter_name_map[j].name);
1156
1157	// If only the filter names were wanted then
1158	// skip to the next filter. In this case
1159	// .options is ignored and may be NULL even
1160	// when the filter doesn't allow NULL options.
1161	if (!show_opts)
1162	break;
1163
1164	if (filters[i].options == NULL) {
1165	if (!filter_name_map[j].allow_null) {
1166	// Filter-specific options
1167	// are missing but with
1168	// this filter the options
1169	// structure is mandatory.
1170	str_free(&dest, allocator);
1171	return LZMA_OPTIONS_ERROR;
1172	}
1173
1174	// .options is allowed to be NULL.
1175	// There is no need to add any
1176	// options to the string.
1177	break;
1178	}
1179
1180	// Options structure is available. Add
1181	// the filter options to the string.
1182	const size_t optmap_count
1183	= (flags & LZMA_STR_ENCODER)
1184	? filter_name_map[j].strfy_encoder
1185	: filter_name_map[j].strfy_decoder;
1186	strfy_filter(&dest, opt_delim,
1187	filter_name_map[j].optmap,
1188	optmap_count,
1189	filters[i].options);
1190	break;
1191	}
1192
1193	++j;
1194	}
1195	}
1196
1197	return str_finish(output_str, &dest, allocator);
1198	}
1199
1200
1201	extern LZMA_API(lzma_ret)
1202	lzma_str_list_filters(char **output_str, lzma_vli filter_id, uint32_t flags,
1203	const lzma_allocator *allocator)
1204	{
1205	// On error *output_str is always set to NULL.
1206	// Do it as the very first step.
1207	if (output_str == NULL)
1208	return LZMA_PROG_ERROR;
1209
1210	*output_str = NULL;
1211
1212	// Validate the flags.
1213	const uint32_t supported_flags
1214	= LZMA_STR_ALL_FILTERS
1215	\| LZMA_STR_ENCODER
1216	\| LZMA_STR_DECODER
1217	\| LZMA_STR_GETOPT_LONG;
1218
1219	if (flags & ~supported_flags)
1220	return LZMA_OPTIONS_ERROR;
1221
1222	// Allocate memory for the output string.
1223	lzma_str dest;
1224	return_if_error(str_init(&dest, allocator));
1225
1226	// If only listing the filter names then separate them with spaces.
1227	// Otherwise use newlines.
1228	const bool show_opts = (flags & (LZMA_STR_ENCODER \| LZMA_STR_DECODER));
1229	const char *filter_delim = show_opts ? "\n" : " ";
1230
1231	const char *opt_delim = (flags & LZMA_STR_GETOPT_LONG) ? "=" : ":";
1232	bool first_filter_printed = false;
1233
1234	for (size_t i = 0; i < ARRAY_SIZE(filter_name_map); ++i) {
1235	// If we are printing only one filter then skip others.
1236	if (filter_id != LZMA_VLI_UNKNOWN
1237	&& filter_id != filter_name_map[i].id)
1238	continue;
1239
1240	// If we are printing only .xz filters then skip the others.
1241	if (filter_name_map[i].id >= LZMA_FILTER_RESERVED_START
1242	&& (flags & LZMA_STR_ALL_FILTERS) == 0
1243	&& filter_id == LZMA_VLI_UNKNOWN)
1244	continue;
1245
1246	// Add a new line if this isn't the first filter being
1247	// written to the string.
1248	if (first_filter_printed)
1249	str_append_str(&dest, filter_delim);
1250
1251	first_filter_printed = true;
1252
1253	if (flags & LZMA_STR_GETOPT_LONG)
1254	str_append_str(&dest, "--");
1255
1256	str_append_str(&dest, filter_name_map[i].name);
1257
1258	// If only the filter names were wanted then continue
1259	// to the next filter.
1260	if (!show_opts)
1261	continue;
1262
1263	const option_map *optmap = filter_name_map[i].optmap;
1264	const char *d = opt_delim;
1265
1266	const size_t end = (flags & LZMA_STR_ENCODER)
1267	? filter_name_map[i].strfy_encoder
1268	: filter_name_map[i].strfy_decoder;
1269
1270	for (size_t j = 0; j < end; ++j) {
1271	// The first option is delimited from the filter
1272	// name using "=" or ":" and the rest of the options
1273	// are separated with ",".
1274	str_append_str(&dest, d);
1275	d = ",";
1276
1277	// optname=<possible_values>
1278	str_append_str(&dest, optmap[j].name);
1279	str_append_str(&dest, "=<");
1280
1281	if (optmap[j].type == OPTMAP_TYPE_LZMA_PRESET) {
1282	// LZMA1/2 preset has its custom help string.
1283	str_append_str(&dest, LZMA12_PRESET_STR);
1284	} else if (optmap[j].flags
1285	& OPTMAP_USE_NAME_VALUE_MAP) {
1286	// Separate the possible option values by "\|".
1287	const name_value_map *m = optmap[j].u.map;
1288	for (size_t k = 0; m[k].name[0] != '\0'; ++k) {
1289	if (k > 0)
1290	str_append_str(&dest, "\|");
1291
1292	str_append_str(&dest, m[k].name);
1293	}
1294	} else {
1295	// Integer range is shown as min-max.
1296	const bool use_byte_suffix = optmap[j].flags
1297	& OPTMAP_USE_BYTE_SUFFIX;
1298	str_append_u32(&dest, optmap[j].u.range.min,
1299	use_byte_suffix);
1300	str_append_str(&dest, "-");
1301	str_append_u32(&dest, optmap[j].u.range.max,
1302	use_byte_suffix);
1303	}
1304
1305	str_append_str(&dest, ">");
1306	}
1307	}
1308
1309	// If no filters were added to the string then it must be because
1310	// the caller provided an unsupported Filter ID.
1311	if (!first_filter_printed) {
1312	str_free(&dest, allocator);
1313	return LZMA_OPTIONS_ERROR;
1314	}
1315
1316	return str_finish(output_str, &dest, allocator);
1317	}

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source: vbox/trunk/src/libs/liblzma-5.4.1/common/string_conversion.c

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