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Rev 55994 Rev 63230
Line 24... Line 24...
24 
		SEQ_UNCOMPRESSED_SIZE,
 24 
		SEQ_UNCOMPRESSED_SIZE,
25 
		SEQ_CODER_INIT,
 25 
		SEQ_CODER_INIT,
26 
		SEQ_CODE,
 26 
		SEQ_CODE,
27 
	} sequence;
 27 
	} sequence;
28 
 
 28 
 
- 
 
 29 
	/// If true, reject files that are unlikely to be .lzma files.
- 
 
 30 
	/// If false, more non-.lzma files get accepted and will give
- 
 
 31 
	/// LZMA_DATA_ERROR either immediately or after a few output bytes.
- 
 
 32 
	bool picky;
- 
 
 33 
 
29 
	/// Position in the header fields
 34 
	/// Position in the header fields
30 
	size_t pos;
 35 
	size_t pos;
31 
 
 36 
 
32 
	/// Uncompressed size decoded from the header
 37 
	/// Uncompressed size decoded from the header
33 
	lzma_vli uncompressed_size;
 38 
	lzma_vli uncompressed_size;
Line 66... Line 71...
66 
	case SEQ_DICTIONARY_SIZE:
 71 
	case SEQ_DICTIONARY_SIZE:
67 
		coder->options.dict_size
 72 
		coder->options.dict_size
68 
				|= (size_t)(in[*in_pos]) << (coder->pos * 8);
 73 
				|= (size_t)(in[*in_pos]) << (coder->pos * 8);
69 
 
 74 
 
70 
		if (++coder->pos == 4) {
 75 
		if (++coder->pos == 4) {
71 
			if (coder->options.dict_size != UINT32_MAX) {
 76 
			if (coder->picky && coder->options.dict_size
- 
 
 77 
					!= UINT32_MAX) {
72 
				// A hack to ditch tons of false positives:
 78 
				// A hack to ditch tons of false positives:
73 
				// We allow only dictionary sizes that are
 79 
				// We allow only dictionary sizes that are
74 
				// 2^n or 2^n + 2^(n-1). LZMA_Alone created
 80 
				// 2^n or 2^n + 2^(n-1). LZMA_Alone created
75 
				// only files with 2^n, but accepts any
 81 
				// only files with 2^n, but accepts any
76 
				// dictionary size. If someone complains, this
 - 
 
77 
				// will be reconsidered.
 82 
				// dictionary size.
78 
				uint32_t d = coder->options.dict_size - 1;
 83 
				uint32_t d = coder->options.dict_size - 1;
79 
				d |= d >> 2;
 84 
				d |= d >> 2;
80 
				d |= d >> 3;
 85 
				d |= d >> 3;
81 
				d |= d >> 4;
 86 
				d |= d >> 4;
82 
				d |= d >> 8;
 87 
				d |= d >> 8;
Line 101... Line 106...
101 
		if (++coder->pos < 8)
 106 
		if (++coder->pos < 8)
102 
			break;
 107 
			break;
103 
 
 108 
 
104 
		// Another hack to ditch false positives: Assume that
 109 
		// Another hack to ditch false positives: Assume that
105 
		// if the uncompressed size is known, it must be less
 110 
		// if the uncompressed size is known, it must be less
106 
		// than 256 GiB. Again, if someone complains, this
 111 
		// than 256 GiB.
107 
		// will be reconsidered.
 112 
		if (coder->picky
108 
		if (coder->uncompressed_size != LZMA_VLI_UNKNOWN
 113 
				&& coder->uncompressed_size != LZMA_VLI_UNKNOWN
109 
				&& coder->uncompressed_size
 114 
				&& coder->uncompressed_size
110 
					>= (LZMA_VLI_C(1) << 38))
 115 
					>= (LZMA_VLI_C(1) << 38))
111 
			return LZMA_FORMAT_ERROR;
 116 
			return LZMA_FORMAT_ERROR;
112 
 
 117 
 
113 
		// Calculate the memory usage so that it is ready
 118 
		// Calculate the memory usage so that it is ready
Line 187... Line 192...
187 
}
 192 
}
188 
 
 193 
 
189 
 
 194 
 
190 
extern lzma_ret
 195 
extern lzma_ret
191 
lzma_alone_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
 196 
lzma_alone_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
192 
		uint64_t memlimit)
 197 
		uint64_t memlimit, bool picky)
193 
{
 198 
{
194 
	lzma_next_coder_init(&lzma_alone_decoder_init, next, allocator);
 199 
	lzma_next_coder_init(&lzma_alone_decoder_init, next, allocator);
195 
 
 200 
 
196 
	if (memlimit == 0)
 201 
	if (memlimit == 0)
197 
		return LZMA_PROG_ERROR;
 202 
		return LZMA_PROG_ERROR;
Line 206... Line 211...
206 
		next->memconfig = &alone_decoder_memconfig;
 211 
		next->memconfig = &alone_decoder_memconfig;
207 
		next->coder->next = LZMA_NEXT_CODER_INIT;
 212 
		next->coder->next = LZMA_NEXT_CODER_INIT;
208 
	}
 213 
	}
209 
 
 214 
 
210 
	next->coder->sequence = SEQ_PROPERTIES;
 215 
	next->coder->sequence = SEQ_PROPERTIES;
- 
 
 216 
	next->coder->picky = picky;
211 
	next->coder->pos = 0;
 217 
	next->coder->pos = 0;
212 
	next->coder->options.dict_size = 0;
 218 
	next->coder->options.dict_size = 0;
213 
	next->coder->options.preset_dict = NULL;
 219 
	next->coder->options.preset_dict = NULL;
214 
	next->coder->options.preset_dict_size = 0;
 220 
	next->coder->options.preset_dict_size = 0;
215 
	next->coder->uncompressed_size = 0;
 221 
	next->coder->uncompressed_size = 0;
Line 221... Line 227...
221 
 
 227 
 
222 
 
 228 
 
223 
extern LZMA_API(lzma_ret)
 229 
extern LZMA_API(lzma_ret)
224 
lzma_alone_decoder(lzma_stream *strm, uint64_t memlimit)
 230 
lzma_alone_decoder(lzma_stream *strm, uint64_t memlimit)
225 
{
 231 
{
226 
	lzma_next_strm_init(lzma_alone_decoder_init, strm, memlimit);
 232 
	lzma_next_strm_init(lzma_alone_decoder_init, strm, memlimit, false);
227 
 
 233 
 
228 
	strm->internal->supported_actions[LZMA_RUN] = true;
 234 
	strm->internal->supported_actions[LZMA_RUN] = true;
229 
	strm->internal->supported_actions[LZMA_FINISH] = true;
 235 
	strm->internal->supported_actions[LZMA_FINISH] = true;
230 
 
 236 
 
231 
	return LZMA_OK;
 237 
	return LZMA_OK;