archival/libunarchive/decompress_unlzma.c

/* vi: set sw=4 ts=4: */
/*
 * Small lzma deflate implementation.
 * Copyright (C) 2006  Aurelien Jacobs <aurel@gnuage.org>
 *
 * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
 * Copyright (C) 1999-2005  Igor Pavlov
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

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

#if ENABLE_FEATURE_LZMA_FAST
#  define speed_inline ALWAYS_INLINE
#else
#  define speed_inline
#endif


typedef struct {
	int fd;
	uint8_t *ptr;

/* Was keeping rc on stack in unlzma and separately allocating buffer,
 * but with "buffer 'attached to' allocated rc" code is smaller: */
	/* uint8_t *buffer; */
#define RC_BUFFER ((uint8_t*)(rc+1))

	uint8_t *buffer_end;

/* Had provisions for variable buffer, but we don't need it here */
	/* int buffer_size; */
#define RC_BUFFER_SIZE 0x10000

	uint32_t code;
	uint32_t range;
	uint32_t bound;
} rc_t;

#define RC_TOP_BITS 24
#define RC_MOVE_BITS 5
#define RC_MODEL_TOTAL_BITS 11


/* Called twice: once at startup and once in rc_normalize() */
static void rc_read(rc_t *rc)
{
	int buffer_size = safe_read(rc->fd, RC_BUFFER, RC_BUFFER_SIZE);
	if (buffer_size <= 0)
		bb_error_msg_and_die("unexpected EOF");
	rc->ptr = RC_BUFFER;
	rc->buffer_end = RC_BUFFER + buffer_size;
}

/* Called once */
static rc_t* rc_init(int fd) /*, int buffer_size) */
{
	int i;
	rc_t *rc;

	rc = xmalloc(sizeof(*rc) + RC_BUFFER_SIZE);

	rc->fd = fd;
	/* rc->buffer_size = buffer_size; */
	rc->buffer_end = RC_BUFFER + RC_BUFFER_SIZE;
	rc->ptr = rc->buffer_end;

	rc->code = 0;
	rc->range = 0xFFFFFFFF;
	for (i = 0; i < 5; i++) {
		if (rc->ptr >= rc->buffer_end)
			rc_read(rc);
		rc->code = (rc->code << 8) | *rc->ptr++;
	}
	return rc;
}

/* Called once  */
static ALWAYS_INLINE void rc_free(rc_t *rc)
{
	free(rc);
}

/* Called twice, but one callsite is in speed_inline'd rc_is_bit_0_helper() */
static void rc_do_normalize(rc_t *rc)
{
	if (rc->ptr >= rc->buffer_end)
		rc_read(rc);
	rc->range <<= 8;
	rc->code = (rc->code << 8) | *rc->ptr++;
}
static ALWAYS_INLINE void rc_normalize(rc_t *rc)
{
	if (rc->range < (1 << RC_TOP_BITS)) {
		rc_do_normalize(rc);
	}
}

/* rc_is_bit_0 is called 9 times */
/* Why rc_is_bit_0_helper exists?
 * Because we want to always expose (rc->code < rc->bound) to optimizer.
 * Thus rc_is_bit_0 is always inlined, and rc_is_bit_0_helper is inlined
 * only if we compile for speed.
 */
static speed_inline uint32_t rc_is_bit_0_helper(rc_t *rc, uint16_t *p)
{
	rc_normalize(rc);
	rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
	return rc->bound;
}
static ALWAYS_INLINE int rc_is_bit_0(rc_t *rc, uint16_t *p)
{
	uint32_t t = rc_is_bit_0_helper(rc, p);
	return rc->code < t;
}

/* Called ~10 times, but very small, thus inlined */
static speed_inline void rc_update_bit_0(rc_t *rc, uint16_t *p)
{
	rc->range = rc->bound;
	*p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
}
static speed_inline void rc_update_bit_1(rc_t *rc, uint16_t *p)
{
	rc->range -= rc->bound;
	rc->code -= rc->bound;
	*p -= *p >> RC_MOVE_BITS;
}

/* Called 4 times in unlzma loop */
static int rc_get_bit(rc_t *rc, uint16_t *p, int *symbol)
{
	if (rc_is_bit_0(rc, p)) {
		rc_update_bit_0(rc, p);
		*symbol *= 2;
		return 0;
	} else {
		rc_update_bit_1(rc, p);
		*symbol = *symbol * 2 + 1;
		return 1;
	}
}

/* Called once */
static ALWAYS_INLINE int rc_direct_bit(rc_t *rc)
{
	rc_normalize(rc);
	rc->range >>= 1;
	if (rc->code >= rc->range) {
		rc->code -= rc->range;
		return 1;
	}
	return 0;
}

/* Called twice */
static speed_inline void
rc_bit_tree_decode(rc_t *rc, uint16_t *p, int num_levels, int *symbol)
{
	int i = num_levels;

	*symbol = 1;
	while (i--)
		rc_get_bit(rc, p + *symbol, symbol);
	*symbol -= 1 << num_levels;
}


typedef struct {
	uint8_t pos;
	uint32_t dict_size;
	uint64_t dst_size;
} __attribute__ ((packed)) lzma_header_t;


/* #defines will force compiler to compute/optimize each one with each usage.
 * Have heart and use enum instead. */
enum {
	LZMA_BASE_SIZE = 1846,
	LZMA_LIT_SIZE  = 768,

	LZMA_NUM_POS_BITS_MAX = 4,

	LZMA_LEN_NUM_LOW_BITS  = 3,
	LZMA_LEN_NUM_MID_BITS  = 3,
	LZMA_LEN_NUM_HIGH_BITS = 8,

	LZMA_LEN_CHOICE     = 0,
	LZMA_LEN_CHOICE_2   = (LZMA_LEN_CHOICE + 1),
	LZMA_LEN_LOW        = (LZMA_LEN_CHOICE_2 + 1),
	LZMA_LEN_MID        = (LZMA_LEN_LOW \
	                      + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS))),
	LZMA_LEN_HIGH       = (LZMA_LEN_MID \
	                      + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS))),
	LZMA_NUM_LEN_PROBS  = (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS)),

	LZMA_NUM_STATES     = 12,
	LZMA_NUM_LIT_STATES = 7,

	LZMA_START_POS_MODEL_INDEX = 4,
	LZMA_END_POS_MODEL_INDEX   = 14,
	LZMA_NUM_FULL_DISTANCES    = (1 << (LZMA_END_POS_MODEL_INDEX >> 1)),

	LZMA_NUM_POS_SLOT_BITS = 6,
	LZMA_NUM_LEN_TO_POS_STATES = 4,

	LZMA_NUM_ALIGN_BITS = 4,

	LZMA_MATCH_MIN_LEN  = 2,

	LZMA_IS_MATCH       = 0,
	LZMA_IS_REP         = (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX)),
	LZMA_IS_REP_G0      = (LZMA_IS_REP + LZMA_NUM_STATES),
	LZMA_IS_REP_G1      = (LZMA_IS_REP_G0 + LZMA_NUM_STATES),
	LZMA_IS_REP_G2      = (LZMA_IS_REP_G1 + LZMA_NUM_STATES),
	LZMA_IS_REP_0_LONG  = (LZMA_IS_REP_G2 + LZMA_NUM_STATES),
	LZMA_POS_SLOT       = (LZMA_IS_REP_0_LONG \
	                      + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX)),
	LZMA_SPEC_POS       = (LZMA_POS_SLOT \
	                      + (LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS)),
	LZMA_ALIGN          = (LZMA_SPEC_POS \
	                      + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX),
	LZMA_LEN_CODER      = (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS)),
	LZMA_REP_LEN_CODER  = (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS),
	LZMA_LITERAL        = (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS),
};


USE_DESKTOP(long long) int FAST_FUNC
unpack_lzma_stream(int src_fd, int dst_fd)
{
	USE_DESKTOP(long long total_written = 0;)
	lzma_header_t header;
	int lc, pb, lp;
	uint32_t pos_state_mask;
	uint32_t literal_pos_mask;
	uint32_t pos;
	uint16_t *p;
	uint16_t *prob;
	uint16_t *prob_lit;
	int num_bits;
	int num_probs;
	rc_t *rc;
	int i, mi;
	uint8_t *buffer;
	uint8_t previous_byte = 0;
	size_t buffer_pos = 0, global_pos = 0;
	int len = 0;
	int state = 0;
	uint32_t rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;

	xread(src_fd, &header, sizeof(header));

	if (header.pos >= (9 * 5 * 5))
		bb_error_msg_and_die("bad header");
	mi = header.pos / 9;
	lc = header.pos % 9;
	pb = mi / 5;
	lp = mi % 5;
	pos_state_mask = (1 << pb) - 1;
	literal_pos_mask = (1 << lp) - 1;

	header.dict_size = SWAP_LE32(header.dict_size);
	header.dst_size = SWAP_LE64(header.dst_size);

	if (header.dict_size == 0)
		header.dict_size = 1;

	buffer = xmalloc(MIN(header.dst_size, header.dict_size));

	num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
	p = xmalloc(num_probs * sizeof(*p));
	num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
	for (i = 0; i < num_probs; i++)
		p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;

	rc = rc_init(src_fd); /*, RC_BUFFER_SIZE); */

	while (global_pos + buffer_pos < header.dst_size) {
		int pos_state = (buffer_pos + global_pos) & pos_state_mask;

		prob = p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
		if (rc_is_bit_0(rc, prob)) {
			mi = 1;
			rc_update_bit_0(rc, prob);
			prob = (p + LZMA_LITERAL
			        + (LZMA_LIT_SIZE * ((((buffer_pos + global_pos) & literal_pos_mask) << lc)
			                            + (previous_byte >> (8 - lc))
			                           )
			          )
			);

			if (state >= LZMA_NUM_LIT_STATES) {
				int match_byte;

				pos = buffer_pos - rep0;
				while (pos >= header.dict_size)
					pos += header.dict_size;
				match_byte = buffer[pos];
				do {
					int bit;

					match_byte <<= 1;
					bit = match_byte & 0x100;
					prob_lit = prob + 0x100 + bit + mi;
					bit ^= (rc_get_bit(rc, prob_lit, &mi) << 8); /* 0x100 or 0 */
					if (bit)
						break;
				} while (mi < 0x100);
			}
			while (mi < 0x100) {
				prob_lit = prob + mi;
				rc_get_bit(rc, prob_lit, &mi);
			}

			state -= 3;
			if (state < 4-3)
				state = 0;
			if (state >= 10-3)
				state -= 6-3;

			previous_byte = (uint8_t) mi;
#if ENABLE_FEATURE_LZMA_FAST
 one_byte1:
			buffer[buffer_pos++] = previous_byte;
			if (buffer_pos == header.dict_size) {
				buffer_pos = 0;
				global_pos += header.dict_size;
				if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
					goto bad;
				USE_DESKTOP(total_written += header.dict_size;)
			}
#else
			len = 1;
			goto one_byte2;
#endif
		} else {
			int offset;
			uint16_t *prob_len;

			rc_update_bit_1(rc, prob);
			prob = p + LZMA_IS_REP + state;
			if (rc_is_bit_0(rc, prob)) {
				rc_update_bit_0(rc, prob);
				rep3 = rep2;
				rep2 = rep1;
				rep1 = rep0;
				state = state < LZMA_NUM_LIT_STATES ? 0 : 3;
				prob = p + LZMA_LEN_CODER;
			} else {
				rc_update_bit_1(rc, prob);
				prob = p + LZMA_IS_REP_G0 + state;
				if (rc_is_bit_0(rc, prob)) {
					rc_update_bit_0(rc, prob);
					prob = (p + LZMA_IS_REP_0_LONG
					        + (state << LZMA_NUM_POS_BITS_MAX)
					        + pos_state
					);
					if (rc_is_bit_0(rc, prob)) {
						rc_update_bit_0(rc, prob);

						state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
#if ENABLE_FEATURE_LZMA_FAST
						pos = buffer_pos - rep0;
						while (pos >= header.dict_size)
							pos += header.dict_size;
						previous_byte = buffer[pos];
						goto one_byte1;
#else
						len = 1;
						goto string;
#endif
					} else {
						rc_update_bit_1(rc, prob);
					}
				} else {
					uint32_t distance;

					rc_update_bit_1(rc, prob);
					prob = p + LZMA_IS_REP_G1 + state;
					if (rc_is_bit_0(rc, prob)) {
						rc_update_bit_0(rc, prob);
						distance = rep1;
					} else {
						rc_update_bit_1(rc, prob);
						prob = p + LZMA_IS_REP_G2 + state;
						if (rc_is_bit_0(rc, prob)) {
							rc_update_bit_0(rc, prob);
							distance = rep2;
						} else {
							rc_update_bit_1(rc, prob);
							distance = rep3;
							rep3 = rep2;
						}
						rep2 = rep1;
					}
					rep1 = rep0;
					rep0 = distance;
				}
				state = state < LZMA_NUM_LIT_STATES ? 8 : 11;
				prob = p + LZMA_REP_LEN_CODER;
			}

			prob_len = prob + LZMA_LEN_CHOICE;
			if (rc_is_bit_0(rc, prob_len)) {
				rc_update_bit_0(rc, prob_len);
				prob_len = (prob + LZMA_LEN_LOW
				            + (pos_state << LZMA_LEN_NUM_LOW_BITS));
				offset = 0;
				num_bits = LZMA_LEN_NUM_LOW_BITS;
			} else {
				rc_update_bit_1(rc, prob_len);
				prob_len = prob + LZMA_LEN_CHOICE_2;
				if (rc_is_bit_0(rc, prob_len)) {
					rc_update_bit_0(rc, prob_len);
					prob_len = (prob + LZMA_LEN_MID
					            + (pos_state << LZMA_LEN_NUM_MID_BITS));
					offset = 1 << LZMA_LEN_NUM_LOW_BITS;
					num_bits = LZMA_LEN_NUM_MID_BITS;
				} else {
					rc_update_bit_1(rc, prob_len);
					prob_len = prob + LZMA_LEN_HIGH;
					offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
					          + (1 << LZMA_LEN_NUM_MID_BITS));
					num_bits = LZMA_LEN_NUM_HIGH_BITS;
				}
			}
			rc_bit_tree_decode(rc, prob_len, num_bits, &len);
			len += offset;

			if (state < 4) {
				int pos_slot;

				state += LZMA_NUM_LIT_STATES;
				prob = p + LZMA_POS_SLOT +
				       ((len < LZMA_NUM_LEN_TO_POS_STATES ? len :
				         LZMA_NUM_LEN_TO_POS_STATES - 1)
				         << LZMA_NUM_POS_SLOT_BITS);
				rc_bit_tree_decode(rc, prob, LZMA_NUM_POS_SLOT_BITS,
								   &pos_slot);
				if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
					num_bits = (pos_slot >> 1) - 1;
					rep0 = 2 | (pos_slot & 1);
					if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
						rep0 <<= num_bits;
						prob = p + LZMA_SPEC_POS + rep0 - pos_slot - 1;
					} else {
						num_bits -= LZMA_NUM_ALIGN_BITS;
						while (num_bits--)
							rep0 = (rep0 << 1) | rc_direct_bit(rc);
						prob = p + LZMA_ALIGN;
						rep0 <<= LZMA_NUM_ALIGN_BITS;
						num_bits = LZMA_NUM_ALIGN_BITS;
					}
					i = 1;
					mi = 1;
					while (num_bits--) {
						if (rc_get_bit(rc, prob + mi, &mi))
							rep0 |= i;
						i <<= 1;
					}
				} else
					rep0 = pos_slot;
				if (++rep0 == 0)
					break;
			}

			len += LZMA_MATCH_MIN_LEN;
 SKIP_FEATURE_LZMA_FAST(string:)
			do {
				pos = buffer_pos - rep0;
				while (pos >= header.dict_size)
					pos += header.dict_size;
				previous_byte = buffer[pos];
 SKIP_FEATURE_LZMA_FAST(one_byte2:)
				buffer[buffer_pos++] = previous_byte;
				if (buffer_pos == header.dict_size) {
					buffer_pos = 0;
					global_pos += header.dict_size;
					if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
						goto bad;
					USE_DESKTOP(total_written += header.dict_size;)
				}
				len--;
			} while (len != 0 && buffer_pos < header.dst_size);
		}
	}

	{
		SKIP_DESKTOP(int total_written = 0; /* success */)
		USE_DESKTOP(total_written += buffer_pos;)
		if (full_write(dst_fd, buffer, buffer_pos) != (ssize_t)buffer_pos) {
 bad:
			total_written = -1; /* failure */
		}
		rc_free(rc);
		free(p);
		free(buffer);
		return total_written;
	}
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Small lzma deflate implementation.
4	* Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
5	*
6	* Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
7	* Copyright (C) 1999-2005 Igor Pavlov
8	*
9	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
10	*/
11
12	#include "libbb.h"
13	#include "unarchive.h"
14
15	#if ENABLE_FEATURE_LZMA_FAST
16	# define speed_inline ALWAYS_INLINE
17	#else
18	# define speed_inline
19	#endif
20
21
22	typedef struct {
23	int fd;
24	uint8_t *ptr;
25
26	/* Was keeping rc on stack in unlzma and separately allocating buffer,
27	* but with "buffer 'attached to' allocated rc" code is smaller: */
28	/* uint8_t buffer; /
29	#define RC_BUFFER ((uint8_t*)(rc+1))
30
31	uint8_t *buffer_end;
32
33	/* Had provisions for variable buffer, but we don't need it here */
34	/* int buffer_size; */
35	#define RC_BUFFER_SIZE 0x10000
36
37	uint32_t code;
38	uint32_t range;
39	uint32_t bound;
40	} rc_t;
41
42	#define RC_TOP_BITS 24
43	#define RC_MOVE_BITS 5
44	#define RC_MODEL_TOTAL_BITS 11
45
46
47	/* Called twice: once at startup and once in rc_normalize() */
48	static void rc_read(rc_t *rc)
49	{
50	int buffer_size = safe_read(rc->fd, RC_BUFFER, RC_BUFFER_SIZE);
51	if (buffer_size <= 0)
52	bb_error_msg_and_die("unexpected EOF");
53	rc->ptr = RC_BUFFER;
54	rc->buffer_end = RC_BUFFER + buffer_size;
55	}
56
57	/* Called once */
58	static rc_t* rc_init(int fd) /, int buffer_size) /
59	{
60	int i;
61	rc_t *rc;
62
63	rc = xmalloc(sizeof(*rc) + RC_BUFFER_SIZE);
64
65	rc->fd = fd;
66	/* rc->buffer_size = buffer_size; */
67	rc->buffer_end = RC_BUFFER + RC_BUFFER_SIZE;
68	rc->ptr = rc->buffer_end;
69
70	rc->code = 0;
71	rc->range = 0xFFFFFFFF;
72	for (i = 0; i < 5; i++) {
73	if (rc->ptr >= rc->buffer_end)
74	rc_read(rc);
75	rc->code = (rc->code << 8) \| *rc->ptr++;
76	}
77	return rc;
78	}
79
80	/* Called once */
81	static ALWAYS_INLINE void rc_free(rc_t *rc)
82	{
83	free(rc);
84	}
85
86	/* Called twice, but one callsite is in speed_inline'd rc_is_bit_0_helper() */
87	static void rc_do_normalize(rc_t *rc)
88	{
89	if (rc->ptr >= rc->buffer_end)
90	rc_read(rc);
91	rc->range <<= 8;
92	rc->code = (rc->code << 8) \| *rc->ptr++;
93	}
94	static ALWAYS_INLINE void rc_normalize(rc_t *rc)
95	{
96	if (rc->range < (1 << RC_TOP_BITS)) {
97	rc_do_normalize(rc);
98	}
99	}
100
101	/* rc_is_bit_0 is called 9 times */
102	/* Why rc_is_bit_0_helper exists?
103	* Because we want to always expose (rc->code < rc->bound) to optimizer.
104	* Thus rc_is_bit_0 is always inlined, and rc_is_bit_0_helper is inlined
105	* only if we compile for speed.
106	*/
107	static speed_inline uint32_t rc_is_bit_0_helper(rc_t rc, uint16_t p)
108	{
109	rc_normalize(rc);
110	rc->bound = p (rc->range >> RC_MODEL_TOTAL_BITS);
111	return rc->bound;
112	}
113	static ALWAYS_INLINE int rc_is_bit_0(rc_t rc, uint16_t p)
114	{
115	uint32_t t = rc_is_bit_0_helper(rc, p);
116	return rc->code < t;
117	}
118
119	/* Called ~10 times, but very small, thus inlined */
120	static speed_inline void rc_update_bit_0(rc_t rc, uint16_t p)
121	{
122	rc->range = rc->bound;
123	p += ((1 << RC_MODEL_TOTAL_BITS) - p) >> RC_MOVE_BITS;
124	}
125	static speed_inline void rc_update_bit_1(rc_t rc, uint16_t p)
126	{
127	rc->range -= rc->bound;
128	rc->code -= rc->bound;
129	p -= p >> RC_MOVE_BITS;
130	}
131
132	/* Called 4 times in unlzma loop */
133	static int rc_get_bit(rc_t rc, uint16_t p, int *symbol)
134	{
135	if (rc_is_bit_0(rc, p)) {
136	rc_update_bit_0(rc, p);
137	symbol = 2;
138	return 0;
139	} else {
140	rc_update_bit_1(rc, p);
141	symbol = symbol * 2 + 1;
142	return 1;
143	}
144	}
145
146	/* Called once */
147	static ALWAYS_INLINE int rc_direct_bit(rc_t *rc)
148	{
149	rc_normalize(rc);
150	rc->range >>= 1;
151	if (rc->code >= rc->range) {
152	rc->code -= rc->range;
153	return 1;
154	}
155	return 0;
156	}
157
158	/* Called twice */
159	static speed_inline void
160	rc_bit_tree_decode(rc_t rc, uint16_t p, int num_levels, int *symbol)
161	{
162	int i = num_levels;
163
164	*symbol = 1;
165	while (i--)
166	rc_get_bit(rc, p + *symbol, symbol);
167	*symbol -= 1 << num_levels;
168	}
169
170
171	typedef struct {
172	uint8_t pos;
173	uint32_t dict_size;
174	uint64_t dst_size;
175	} __attribute__ ((packed)) lzma_header_t;
176
177
178	/* #defines will force compiler to compute/optimize each one with each usage.
179	* Have heart and use enum instead. */
180	enum {
181	LZMA_BASE_SIZE = 1846,
182	LZMA_LIT_SIZE = 768,
183
184	LZMA_NUM_POS_BITS_MAX = 4,
185
186	LZMA_LEN_NUM_LOW_BITS = 3,
187	LZMA_LEN_NUM_MID_BITS = 3,
188	LZMA_LEN_NUM_HIGH_BITS = 8,
189
190	LZMA_LEN_CHOICE = 0,
191	LZMA_LEN_CHOICE_2 = (LZMA_LEN_CHOICE + 1),
192	LZMA_LEN_LOW = (LZMA_LEN_CHOICE_2 + 1),
193	LZMA_LEN_MID = (LZMA_LEN_LOW \
194	+ (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS))),
195	LZMA_LEN_HIGH = (LZMA_LEN_MID \
196	+ (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS))),
197	LZMA_NUM_LEN_PROBS = (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS)),
198
199	LZMA_NUM_STATES = 12,
200	LZMA_NUM_LIT_STATES = 7,
201
202	LZMA_START_POS_MODEL_INDEX = 4,
203	LZMA_END_POS_MODEL_INDEX = 14,
204	LZMA_NUM_FULL_DISTANCES = (1 << (LZMA_END_POS_MODEL_INDEX >> 1)),
205
206	LZMA_NUM_POS_SLOT_BITS = 6,
207	LZMA_NUM_LEN_TO_POS_STATES = 4,
208
209	LZMA_NUM_ALIGN_BITS = 4,
210
211	LZMA_MATCH_MIN_LEN = 2,
212
213	LZMA_IS_MATCH = 0,
214	LZMA_IS_REP = (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX)),
215	LZMA_IS_REP_G0 = (LZMA_IS_REP + LZMA_NUM_STATES),
216	LZMA_IS_REP_G1 = (LZMA_IS_REP_G0 + LZMA_NUM_STATES),
217	LZMA_IS_REP_G2 = (LZMA_IS_REP_G1 + LZMA_NUM_STATES),
218	LZMA_IS_REP_0_LONG = (LZMA_IS_REP_G2 + LZMA_NUM_STATES),
219	LZMA_POS_SLOT = (LZMA_IS_REP_0_LONG \
220	+ (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX)),
221	LZMA_SPEC_POS = (LZMA_POS_SLOT \
222	+ (LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS)),
223	LZMA_ALIGN = (LZMA_SPEC_POS \
224	+ LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX),
225	LZMA_LEN_CODER = (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS)),
226	LZMA_REP_LEN_CODER = (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS),
227	LZMA_LITERAL = (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS),
228	};
229
230
231	USE_DESKTOP(long long) int FAST_FUNC
232	unpack_lzma_stream(int src_fd, int dst_fd)
233	{
234	USE_DESKTOP(long long total_written = 0;)
235	lzma_header_t header;
236	int lc, pb, lp;
237	uint32_t pos_state_mask;
238	uint32_t literal_pos_mask;
239	uint32_t pos;
240	uint16_t *p;
241	uint16_t *prob;
242	uint16_t *prob_lit;
243	int num_bits;
244	int num_probs;
245	rc_t *rc;
246	int i, mi;
247	uint8_t *buffer;
248	uint8_t previous_byte = 0;
249	size_t buffer_pos = 0, global_pos = 0;
250	int len = 0;
251	int state = 0;
252	uint32_t rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
253
254	xread(src_fd, &header, sizeof(header));
255
256	if (header.pos >= (9 * 5 * 5))
257	bb_error_msg_and_die("bad header");
258	mi = header.pos / 9;
259	lc = header.pos % 9;
260	pb = mi / 5;
261	lp = mi % 5;
262	pos_state_mask = (1 << pb) - 1;
263	literal_pos_mask = (1 << lp) - 1;
264
265	header.dict_size = SWAP_LE32(header.dict_size);
266	header.dst_size = SWAP_LE64(header.dst_size);
267
268	if (header.dict_size == 0)
269	header.dict_size = 1;
270
271	buffer = xmalloc(MIN(header.dst_size, header.dict_size));
272
273	num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
274	p = xmalloc(num_probs * sizeof(*p));
275	num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
276	for (i = 0; i < num_probs; i++)
277	p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
278
279	rc = rc_init(src_fd); /, RC_BUFFER_SIZE); /
280
281	while (global_pos + buffer_pos < header.dst_size) {
282	int pos_state = (buffer_pos + global_pos) & pos_state_mask;
283
284	prob = p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
285	if (rc_is_bit_0(rc, prob)) {
286	mi = 1;
287	rc_update_bit_0(rc, prob);
288	prob = (p + LZMA_LITERAL
289	+ (LZMA_LIT_SIZE * ((((buffer_pos + global_pos) & literal_pos_mask) << lc)
290	+ (previous_byte >> (8 - lc))
291	)
292	)
293	);
294
295	if (state >= LZMA_NUM_LIT_STATES) {
296	int match_byte;
297
298	pos = buffer_pos - rep0;
299	while (pos >= header.dict_size)
300	pos += header.dict_size;
301	match_byte = buffer[pos];
302	do {
303	int bit;
304
305	match_byte <<= 1;
306	bit = match_byte & 0x100;
307	prob_lit = prob + 0x100 + bit + mi;
308	bit ^= (rc_get_bit(rc, prob_lit, &mi) << 8); /* 0x100 or 0 */
309	if (bit)
310	break;
311	} while (mi < 0x100);
312	}
313	while (mi < 0x100) {
314	prob_lit = prob + mi;
315	rc_get_bit(rc, prob_lit, &mi);
316	}
317
318	state -= 3;
319	if (state < 4-3)
320	state = 0;
321	if (state >= 10-3)
322	state -= 6-3;
323
324	previous_byte = (uint8_t) mi;
325	#if ENABLE_FEATURE_LZMA_FAST
326	one_byte1:
327	buffer[buffer_pos++] = previous_byte;
328	if (buffer_pos == header.dict_size) {
329	buffer_pos = 0;
330	global_pos += header.dict_size;
331	if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
332	goto bad;
333	USE_DESKTOP(total_written += header.dict_size;)
334	}
335	#else
336	len = 1;
337	goto one_byte2;
338	#endif
339	} else {
340	int offset;
341	uint16_t *prob_len;
342
343	rc_update_bit_1(rc, prob);
344	prob = p + LZMA_IS_REP + state;
345	if (rc_is_bit_0(rc, prob)) {
346	rc_update_bit_0(rc, prob);
347	rep3 = rep2;
348	rep2 = rep1;
349	rep1 = rep0;
350	state = state < LZMA_NUM_LIT_STATES ? 0 : 3;
351	prob = p + LZMA_LEN_CODER;
352	} else {
353	rc_update_bit_1(rc, prob);
354	prob = p + LZMA_IS_REP_G0 + state;
355	if (rc_is_bit_0(rc, prob)) {
356	rc_update_bit_0(rc, prob);
357	prob = (p + LZMA_IS_REP_0_LONG
358	+ (state << LZMA_NUM_POS_BITS_MAX)
359	+ pos_state
360	);
361	if (rc_is_bit_0(rc, prob)) {
362	rc_update_bit_0(rc, prob);
363
364	state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
365	#if ENABLE_FEATURE_LZMA_FAST
366	pos = buffer_pos - rep0;
367	while (pos >= header.dict_size)
368	pos += header.dict_size;
369	previous_byte = buffer[pos];
370	goto one_byte1;
371	#else
372	len = 1;
373	goto string;
374	#endif
375	} else {
376	rc_update_bit_1(rc, prob);
377	}
378	} else {
379	uint32_t distance;
380
381	rc_update_bit_1(rc, prob);
382	prob = p + LZMA_IS_REP_G1 + state;
383	if (rc_is_bit_0(rc, prob)) {
384	rc_update_bit_0(rc, prob);
385	distance = rep1;
386	} else {
387	rc_update_bit_1(rc, prob);
388	prob = p + LZMA_IS_REP_G2 + state;
389	if (rc_is_bit_0(rc, prob)) {
390	rc_update_bit_0(rc, prob);
391	distance = rep2;
392	} else {
393	rc_update_bit_1(rc, prob);
394	distance = rep3;
395	rep3 = rep2;
396	}
397	rep2 = rep1;
398	}
399	rep1 = rep0;
400	rep0 = distance;
401	}
402	state = state < LZMA_NUM_LIT_STATES ? 8 : 11;
403	prob = p + LZMA_REP_LEN_CODER;
404	}
405
406	prob_len = prob + LZMA_LEN_CHOICE;
407	if (rc_is_bit_0(rc, prob_len)) {
408	rc_update_bit_0(rc, prob_len);
409	prob_len = (prob + LZMA_LEN_LOW
410	+ (pos_state << LZMA_LEN_NUM_LOW_BITS));
411	offset = 0;
412	num_bits = LZMA_LEN_NUM_LOW_BITS;
413	} else {
414	rc_update_bit_1(rc, prob_len);
415	prob_len = prob + LZMA_LEN_CHOICE_2;
416	if (rc_is_bit_0(rc, prob_len)) {
417	rc_update_bit_0(rc, prob_len);
418	prob_len = (prob + LZMA_LEN_MID
419	+ (pos_state << LZMA_LEN_NUM_MID_BITS));
420	offset = 1 << LZMA_LEN_NUM_LOW_BITS;
421	num_bits = LZMA_LEN_NUM_MID_BITS;
422	} else {
423	rc_update_bit_1(rc, prob_len);
424	prob_len = prob + LZMA_LEN_HIGH;
425	offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
426	+ (1 << LZMA_LEN_NUM_MID_BITS));
427	num_bits = LZMA_LEN_NUM_HIGH_BITS;
428	}
429	}
430	rc_bit_tree_decode(rc, prob_len, num_bits, &len);
431	len += offset;
432
433	if (state < 4) {
434	int pos_slot;
435
436	state += LZMA_NUM_LIT_STATES;
437	prob = p + LZMA_POS_SLOT +
438	((len < LZMA_NUM_LEN_TO_POS_STATES ? len :
439	LZMA_NUM_LEN_TO_POS_STATES - 1)
440	<< LZMA_NUM_POS_SLOT_BITS);
441	rc_bit_tree_decode(rc, prob, LZMA_NUM_POS_SLOT_BITS,
442	&pos_slot);
443	if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
444	num_bits = (pos_slot >> 1) - 1;
445	rep0 = 2 \| (pos_slot & 1);
446	if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
447	rep0 <<= num_bits;
448	prob = p + LZMA_SPEC_POS + rep0 - pos_slot - 1;
449	} else {
450	num_bits -= LZMA_NUM_ALIGN_BITS;
451	while (num_bits--)
452	rep0 = (rep0 << 1) \| rc_direct_bit(rc);
453	prob = p + LZMA_ALIGN;
454	rep0 <<= LZMA_NUM_ALIGN_BITS;
455	num_bits = LZMA_NUM_ALIGN_BITS;
456	}
457	i = 1;
458	mi = 1;
459	while (num_bits--) {
460	if (rc_get_bit(rc, prob + mi, &mi))
461	rep0 \|= i;
462	i <<= 1;
463	}
464	} else
465	rep0 = pos_slot;
466	if (++rep0 == 0)
467	break;
468	}
469
470	len += LZMA_MATCH_MIN_LEN;
471	SKIP_FEATURE_LZMA_FAST(string:)
472	do {
473	pos = buffer_pos - rep0;
474	while (pos >= header.dict_size)
475	pos += header.dict_size;
476	previous_byte = buffer[pos];
477	SKIP_FEATURE_LZMA_FAST(one_byte2:)
478	buffer[buffer_pos++] = previous_byte;
479	if (buffer_pos == header.dict_size) {
480	buffer_pos = 0;
481	global_pos += header.dict_size;
482	if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
483	goto bad;
484	USE_DESKTOP(total_written += header.dict_size;)
485	}
486	len--;
487	} while (len != 0 && buffer_pos < header.dst_size);
488	}
489	}
490
491	{
492	SKIP_DESKTOP(int total_written = 0; /* success */)
493	USE_DESKTOP(total_written += buffer_pos;)
494	if (full_write(dst_fd, buffer, buffer_pos) != (ssize_t)buffer_pos) {
495	bad:
496	total_written = -1; /* failure */
497	}
498	rc_free(rc);
499	free(p);
500	free(buffer);
501	return total_written;
502	}
503	}