348 lines
9.5 KiB
C
348 lines
9.5 KiB
C
/*
|
|
* 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
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
#include <unistd.h>
|
|
#include <stdio.h>
|
|
#include <byteswap.h>
|
|
|
|
#include "libbb.h"
|
|
|
|
#include "rangecoder.h"
|
|
|
|
|
|
typedef struct {
|
|
uint8_t pos;
|
|
uint32_t dict_size;
|
|
uint64_t dst_size;
|
|
} __attribute__ ((packed)) lzma_header_t;
|
|
|
|
|
|
#define LZMA_BASE_SIZE 1846
|
|
#define LZMA_LIT_SIZE 768
|
|
|
|
#define LZMA_NUM_POS_BITS_MAX 4
|
|
|
|
#define LZMA_LEN_NUM_LOW_BITS 3
|
|
#define LZMA_LEN_NUM_MID_BITS 3
|
|
#define LZMA_LEN_NUM_HIGH_BITS 8
|
|
|
|
#define LZMA_LEN_CHOICE 0
|
|
#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
|
|
#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
|
|
#define LZMA_LEN_MID (LZMA_LEN_LOW \
|
|
+ (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
|
|
#define LZMA_LEN_HIGH (LZMA_LEN_MID \
|
|
+(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
|
|
#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
|
|
|
|
#define LZMA_NUM_STATES 12
|
|
#define LZMA_NUM_LIT_STATES 7
|
|
|
|
#define LZMA_START_POS_MODEL_INDEX 4
|
|
#define LZMA_END_POS_MODEL_INDEX 14
|
|
#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
|
|
|
|
#define LZMA_NUM_POS_SLOT_BITS 6
|
|
#define LZMA_NUM_LEN_TO_POS_STATES 4
|
|
|
|
#define LZMA_NUM_ALIGN_BITS 4
|
|
|
|
#define LZMA_MATCH_MIN_LEN 2
|
|
|
|
#define LZMA_IS_MATCH 0
|
|
#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES <<LZMA_NUM_POS_BITS_MAX))
|
|
#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
|
|
#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
|
|
#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
|
|
#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
|
|
#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
|
|
+ (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
|
|
#define LZMA_SPEC_POS (LZMA_POS_SLOT \
|
|
+(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
|
|
#define LZMA_ALIGN (LZMA_SPEC_POS \
|
|
+ LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
|
|
#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
|
|
#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
|
|
#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
|
|
|
|
|
|
int unlzma(int src_fd, int dst_fd)
|
|
{
|
|
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;
|
|
|
|
if (read(src_fd, &header, sizeof(header)) != sizeof(header))
|
|
bb_error_msg_and_die("can't read 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;
|
|
|
|
#if __BYTE_ORDER == __BIG_ENDIAN
|
|
header.dict_size = bswap_32(header.dict_size);
|
|
header.dst_size = bswap_64(header.dst_size);
|
|
#endif /* __BYTE_ORDER */
|
|
|
|
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_init(&rc, src_fd, 0x10000);
|
|
|
|
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;
|
|
if (rc_get_bit(&rc, prob_lit, &mi)) {
|
|
if (!bit)
|
|
break;
|
|
} else {
|
|
if (bit)
|
|
break;
|
|
}
|
|
} while (mi < 0x100);
|
|
}
|
|
while (mi < 0x100) {
|
|
prob_lit = prob + mi;
|
|
rc_get_bit(&rc, prob_lit, &mi);
|
|
}
|
|
previous_byte = (uint8_t) mi;
|
|
|
|
buffer[buffer_pos++] = previous_byte;
|
|
if (buffer_pos == header.dict_size) {
|
|
buffer_pos = 0;
|
|
global_pos += header.dict_size;
|
|
write(dst_fd, buffer, header.dict_size);
|
|
}
|
|
if (state < 4)
|
|
state = 0;
|
|
else if (state < 10)
|
|
state -= 3;
|
|
else
|
|
state -= 6;
|
|
} 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;
|
|
pos = buffer_pos - rep0;
|
|
while (pos >= header.dict_size)
|
|
pos += header.dict_size;
|
|
previous_byte = buffer[pos];
|
|
buffer[buffer_pos++] = previous_byte;
|
|
if (buffer_pos == header.dict_size) {
|
|
buffer_pos = 0;
|
|
global_pos += header.dict_size;
|
|
write(dst_fd, buffer, header.dict_size);
|
|
}
|
|
continue;
|
|
} 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;
|
|
|
|
do {
|
|
pos = buffer_pos - rep0;
|
|
while (pos >= header.dict_size)
|
|
pos += header.dict_size;
|
|
previous_byte = buffer[pos];
|
|
buffer[buffer_pos++] = previous_byte;
|
|
if (buffer_pos == header.dict_size) {
|
|
buffer_pos = 0;
|
|
global_pos += header.dict_size;
|
|
write(dst_fd, buffer, header.dict_size);
|
|
}
|
|
len--;
|
|
} while (len != 0 && buffer_pos < header.dst_size);
|
|
}
|
|
}
|
|
|
|
write(dst_fd, buffer, buffer_pos);
|
|
rc_free(&rc);
|
|
return 0;
|
|
}
|
|
|
|
/* vi:set ts=4: */
|