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	niro	532	/* 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	niro	816	#if ENABLE_FEATURE_LZMA_FAST
16			# define speed_inline ALWAYS_INLINE
17	niro	532	#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	niro	816	static void rc_read(rc_t *rc)
49	niro	532	{
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	niro	816	rc_t *rc;
62	niro	532
63	niro	816	rc = xmalloc(sizeof(*rc) + RC_BUFFER_SIZE);
64	niro	532
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	niro	816	static ALWAYS_INLINE void rc_free(rc_t *rc)
82	niro	532	{
83	niro	816	free(rc);
84	niro	532	}
85
86			/* Called twice, but one callsite is in speed_inline'd rc_is_bit_0_helper() */
87	niro	816	static void rc_do_normalize(rc_t *rc)
88	niro	532	{
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	niro	816	static ALWAYS_INLINE void rc_normalize(rc_t *rc)
95	niro	532	{
96			if (rc->range < (1 << RC_TOP_BITS)) {
97			rc_do_normalize(rc);
98			}
99			}
100
101	niro	816	/* rc_is_bit_0 is called 9 times */
102	niro	532	/* Why rc_is_bit_0_helper exists?
103	niro	816	* 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	niro	532	*/
107	niro	816	static speed_inline uint32_t rc_is_bit_0_helper(rc_t rc, uint16_t p)
108	niro	532	{
109			rc_normalize(rc);
110			rc->bound = p (rc->range >> RC_MODEL_TOTAL_BITS);
111			return rc->bound;
112			}
113	niro	816	static ALWAYS_INLINE int rc_is_bit_0(rc_t rc, uint16_t p)
114	niro	532	{
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	niro	816	static speed_inline void rc_update_bit_0(rc_t rc, uint16_t p)
121	niro	532	{
122			rc->range = rc->bound;
123			p += ((1 << RC_MODEL_TOTAL_BITS) - p) >> RC_MOVE_BITS;
124			}
125	niro	816	static speed_inline void rc_update_bit_1(rc_t rc, uint16_t p)
126	niro	532	{
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	niro	816	static int rc_get_bit(rc_t rc, uint16_t p, int *symbol)
134	niro	532	{
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	niro	816	static ALWAYS_INLINE int rc_direct_bit(rc_t *rc)
148	niro	532	{
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	niro	816	rc_bit_tree_decode(rc_t rc, uint16_t p, int num_levels, int *symbol)
161	niro	532	{
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	niro	816	USE_DESKTOP(long long) int FAST_FUNC
232			unpack_lzma_stream(int src_fd, int dst_fd)
233	niro	532	{
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	niro	816	prob = p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
285	niro	532	if (rc_is_bit_0(rc, prob)) {
286			mi = 1;
287			rc_update_bit_0(rc, prob);
288	niro	816	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	niro	532
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	niro	816	bit ^= (rc_get_bit(rc, prob_lit, &mi) << 8); /* 0x100 or 0 */
309			if (bit)
310			break;
311	niro	532	} while (mi < 0x100);
312			}
313			while (mi < 0x100) {
314			prob_lit = prob + mi;
315			rc_get_bit(rc, prob_lit, &mi);
316			}
317	niro	816
318			state -= 3;
319			if (state < 4-3)
320			state = 0;
321			if (state >= 10-3)
322			state -= 6-3;
323
324	niro	532	previous_byte = (uint8_t) mi;
325	niro	816	#if ENABLE_FEATURE_LZMA_FAST
326			one_byte1:
327	niro	532	buffer[buffer_pos++] = previous_byte;
328			if (buffer_pos == header.dict_size) {
329			buffer_pos = 0;
330			global_pos += header.dict_size;
331	niro	816	if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
332	niro	532	goto bad;
333			USE_DESKTOP(total_written += header.dict_size;)
334			}
335	niro	816	#else
336			len = 1;
337			goto one_byte2;
338			#endif
339	niro	532	} 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	niro	816	+ (state << LZMA_NUM_POS_BITS_MAX)
359			+ pos_state
360			);
361	niro	532	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	niro	816	#if ENABLE_FEATURE_LZMA_FAST
366	niro	532	pos = buffer_pos - rep0;
367			while (pos >= header.dict_size)
368			pos += header.dict_size;
369			previous_byte = buffer[pos];
370	niro	816	goto one_byte1;
371			#else
372			len = 1;
373			goto string;
374			#endif
375	niro	532	} 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	niro	816	+ (pos_state << LZMA_LEN_NUM_LOW_BITS));
411	niro	532	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	niro	816	+ (pos_state << LZMA_LEN_NUM_MID_BITS));
420	niro	532	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	niro	816	+ (1 << LZMA_LEN_NUM_MID_BITS));
427	niro	532	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	niro	816	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	niro	532	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	niro	816	SKIP_FEATURE_LZMA_FAST(string:)
472	niro	532	do {
473			pos = buffer_pos - rep0;
474			while (pos >= header.dict_size)
475			pos += header.dict_size;
476			previous_byte = buffer[pos];
477	niro	816	SKIP_FEATURE_LZMA_FAST(one_byte2:)
478	niro	532	buffer[buffer_pos++] = previous_byte;
479			if (buffer_pos == header.dict_size) {
480			buffer_pos = 0;
481			global_pos += header.dict_size;
482	niro	816	if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
483	niro	532	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	niro	816	{
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	niro	532	bad:
496	niro	816	total_written = -1; /* failure */
497			}
498	niro	532	rc_free(rc);
499	niro	816	free(p);
500			free(buffer);
501			return total_written;
502	niro	532	}
503			}