mirror of
https://github.com/sheumann/hush.git
synced 2024-12-27 16:31:24 +00:00
421 lines
9.1 KiB
C
421 lines
9.1 KiB
C
/* implementation of the LZO1X decompression algorithm
|
|
|
|
This file is part of the LZO real-time data compression library.
|
|
|
|
Copyright (C) 1996..2008 Markus Franz Xaver Johannes Oberhumer
|
|
All Rights Reserved.
|
|
|
|
Markus F.X.J. Oberhumer <markus@oberhumer.com>
|
|
http://www.oberhumer.com/opensource/lzo/
|
|
|
|
The LZO library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU General Public License as
|
|
published by the Free Software Foundation; either version 2 of
|
|
the License, or (at your option) any later version.
|
|
|
|
The LZO library 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with the LZO library; see the file COPYING.
|
|
If not, write to the Free Software Foundation, Inc.,
|
|
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*/
|
|
#include "libbb.h"
|
|
#include "liblzo.h"
|
|
|
|
/***********************************************************************
|
|
// decompress a block of data.
|
|
************************************************************************/
|
|
/* safe decompression with overrun testing */
|
|
int lzo1x_decompress_safe(const uint8_t* in, unsigned in_len,
|
|
uint8_t* out, unsigned* out_len,
|
|
void* wrkmem UNUSED_PARAM)
|
|
{
|
|
register uint8_t* op;
|
|
register const uint8_t* ip;
|
|
register unsigned t;
|
|
#if defined(COPY_DICT)
|
|
unsigned m_off;
|
|
const uint8_t* dict_end;
|
|
#else
|
|
register const uint8_t* m_pos = NULL; /* possibly not needed */
|
|
#endif
|
|
const uint8_t* const ip_end = in + in_len;
|
|
#if defined(HAVE_ANY_OP)
|
|
uint8_t* const op_end = out + *out_len;
|
|
#endif
|
|
#if defined(LZO1Z)
|
|
unsigned last_m_off = 0;
|
|
#endif
|
|
|
|
// LZO_UNUSED(wrkmem);
|
|
|
|
#if defined(COPY_DICT)
|
|
if (dict) {
|
|
if (dict_len > M4_MAX_OFFSET) {
|
|
dict += dict_len - M4_MAX_OFFSET;
|
|
dict_len = M4_MAX_OFFSET;
|
|
}
|
|
dict_end = dict + dict_len;
|
|
} else {
|
|
dict_len = 0;
|
|
dict_end = NULL;
|
|
}
|
|
#endif /* COPY_DICT */
|
|
|
|
*out_len = 0;
|
|
|
|
op = out;
|
|
ip = in;
|
|
|
|
if (*ip > 17) {
|
|
t = *ip++ - 17;
|
|
if (t < 4)
|
|
goto match_next;
|
|
assert(t > 0); NEED_OP(t); NEED_IP(t+1);
|
|
do *op++ = *ip++; while (--t > 0);
|
|
goto first_literal_run;
|
|
}
|
|
|
|
while (TEST_IP && TEST_OP) {
|
|
t = *ip++;
|
|
if (t >= 16)
|
|
goto match;
|
|
/* a literal run */
|
|
if (t == 0) {
|
|
NEED_IP(1);
|
|
while (*ip == 0) {
|
|
t += 255;
|
|
ip++;
|
|
NEED_IP(1);
|
|
}
|
|
t += 15 + *ip++;
|
|
}
|
|
/* copy literals */
|
|
assert(t > 0);
|
|
NEED_OP(t+3);
|
|
NEED_IP(t+4);
|
|
#if defined(LZO_UNALIGNED_OK_4) || defined(LZO_ALIGNED_OK_4)
|
|
# if !defined(LZO_UNALIGNED_OK_4)
|
|
if (PTR_ALIGNED2_4(op, ip))
|
|
# endif
|
|
{
|
|
COPY4(op, ip);
|
|
op += 4;
|
|
ip += 4;
|
|
if (--t > 0) {
|
|
if (t >= 4) {
|
|
do {
|
|
COPY4(op, ip);
|
|
op += 4;
|
|
ip += 4;
|
|
t -= 4;
|
|
} while (t >= 4);
|
|
if (t > 0)
|
|
do *op++ = *ip++; while (--t > 0);
|
|
} else {
|
|
do *op++ = *ip++; while (--t > 0);
|
|
}
|
|
}
|
|
}
|
|
# if !defined(LZO_UNALIGNED_OK_4)
|
|
else
|
|
# endif
|
|
#endif
|
|
#if !defined(LZO_UNALIGNED_OK_4)
|
|
{
|
|
*op++ = *ip++;
|
|
*op++ = *ip++;
|
|
*op++ = *ip++;
|
|
do *op++ = *ip++; while (--t > 0);
|
|
}
|
|
#endif
|
|
|
|
first_literal_run:
|
|
t = *ip++;
|
|
if (t >= 16)
|
|
goto match;
|
|
#if defined(COPY_DICT)
|
|
#if defined(LZO1Z)
|
|
m_off = (1 + M2_MAX_OFFSET) + (t << 6) + (*ip++ >> 2);
|
|
last_m_off = m_off;
|
|
#else
|
|
m_off = (1 + M2_MAX_OFFSET) + (t >> 2) + (*ip++ << 2);
|
|
#endif
|
|
NEED_OP(3);
|
|
t = 3; COPY_DICT(t,m_off)
|
|
#else /* !COPY_DICT */
|
|
#if defined(LZO1Z)
|
|
t = (1 + M2_MAX_OFFSET) + (t << 6) + (*ip++ >> 2);
|
|
m_pos = op - t;
|
|
last_m_off = t;
|
|
#else
|
|
m_pos = op - (1 + M2_MAX_OFFSET);
|
|
m_pos -= t >> 2;
|
|
m_pos -= *ip++ << 2;
|
|
#endif
|
|
TEST_LB(m_pos); NEED_OP(3);
|
|
*op++ = *m_pos++;
|
|
*op++ = *m_pos++;
|
|
*op++ = *m_pos;
|
|
#endif /* COPY_DICT */
|
|
goto match_done;
|
|
|
|
/* handle matches */
|
|
do {
|
|
match:
|
|
if (t >= 64) { /* a M2 match */
|
|
#if defined(COPY_DICT)
|
|
#if defined(LZO1X)
|
|
m_off = 1 + ((t >> 2) & 7) + (*ip++ << 3);
|
|
t = (t >> 5) - 1;
|
|
#elif defined(LZO1Y)
|
|
m_off = 1 + ((t >> 2) & 3) + (*ip++ << 2);
|
|
t = (t >> 4) - 3;
|
|
#elif defined(LZO1Z)
|
|
m_off = t & 0x1f;
|
|
if (m_off >= 0x1c)
|
|
m_off = last_m_off;
|
|
else {
|
|
m_off = 1 + (m_off << 6) + (*ip++ >> 2);
|
|
last_m_off = m_off;
|
|
}
|
|
t = (t >> 5) - 1;
|
|
#endif
|
|
#else /* !COPY_DICT */
|
|
#if defined(LZO1X)
|
|
m_pos = op - 1;
|
|
m_pos -= (t >> 2) & 7;
|
|
m_pos -= *ip++ << 3;
|
|
t = (t >> 5) - 1;
|
|
#elif defined(LZO1Y)
|
|
m_pos = op - 1;
|
|
m_pos -= (t >> 2) & 3;
|
|
m_pos -= *ip++ << 2;
|
|
t = (t >> 4) - 3;
|
|
#elif defined(LZO1Z)
|
|
{
|
|
unsigned off = t & 0x1f;
|
|
m_pos = op;
|
|
if (off >= 0x1c) {
|
|
assert(last_m_off > 0);
|
|
m_pos -= last_m_off;
|
|
} else {
|
|
off = 1 + (off << 6) + (*ip++ >> 2);
|
|
m_pos -= off;
|
|
last_m_off = off;
|
|
}
|
|
}
|
|
t = (t >> 5) - 1;
|
|
#endif
|
|
TEST_LB(m_pos); assert(t > 0); NEED_OP(t+3-1);
|
|
goto copy_match;
|
|
#endif /* COPY_DICT */
|
|
}
|
|
else if (t >= 32) { /* a M3 match */
|
|
t &= 31;
|
|
if (t == 0) {
|
|
NEED_IP(1);
|
|
while (*ip == 0) {
|
|
t += 255;
|
|
ip++;
|
|
NEED_IP(1);
|
|
}
|
|
t += 31 + *ip++;
|
|
}
|
|
#if defined(COPY_DICT)
|
|
#if defined(LZO1Z)
|
|
m_off = 1 + (ip[0] << 6) + (ip[1] >> 2);
|
|
last_m_off = m_off;
|
|
#else
|
|
m_off = 1 + (ip[0] >> 2) + (ip[1] << 6);
|
|
#endif
|
|
#else /* !COPY_DICT */
|
|
#if defined(LZO1Z)
|
|
{
|
|
unsigned off = 1 + (ip[0] << 6) + (ip[1] >> 2);
|
|
m_pos = op - off;
|
|
last_m_off = off;
|
|
}
|
|
#elif defined(LZO_UNALIGNED_OK_2) && defined(LZO_ABI_LITTLE_ENDIAN)
|
|
m_pos = op - 1;
|
|
m_pos -= (* (const lzo_ushortp) ip) >> 2;
|
|
#else
|
|
m_pos = op - 1;
|
|
m_pos -= (ip[0] >> 2) + (ip[1] << 6);
|
|
#endif
|
|
#endif /* COPY_DICT */
|
|
ip += 2;
|
|
}
|
|
else if (t >= 16) { /* a M4 match */
|
|
#if defined(COPY_DICT)
|
|
m_off = (t & 8) << 11;
|
|
#else /* !COPY_DICT */
|
|
m_pos = op;
|
|
m_pos -= (t & 8) << 11;
|
|
#endif /* COPY_DICT */
|
|
t &= 7;
|
|
if (t == 0) {
|
|
NEED_IP(1);
|
|
while (*ip == 0) {
|
|
t += 255;
|
|
ip++;
|
|
NEED_IP(1);
|
|
}
|
|
t += 7 + *ip++;
|
|
}
|
|
#if defined(COPY_DICT)
|
|
#if defined(LZO1Z)
|
|
m_off += (ip[0] << 6) + (ip[1] >> 2);
|
|
#else
|
|
m_off += (ip[0] >> 2) + (ip[1] << 6);
|
|
#endif
|
|
ip += 2;
|
|
if (m_off == 0)
|
|
goto eof_found;
|
|
m_off += 0x4000;
|
|
#if defined(LZO1Z)
|
|
last_m_off = m_off;
|
|
#endif
|
|
#else /* !COPY_DICT */
|
|
#if defined(LZO1Z)
|
|
m_pos -= (ip[0] << 6) + (ip[1] >> 2);
|
|
#elif defined(LZO_UNALIGNED_OK_2) && defined(LZO_ABI_LITTLE_ENDIAN)
|
|
m_pos -= (* (const lzo_ushortp) ip) >> 2;
|
|
#else
|
|
m_pos -= (ip[0] >> 2) + (ip[1] << 6);
|
|
#endif
|
|
ip += 2;
|
|
if (m_pos == op)
|
|
goto eof_found;
|
|
m_pos -= 0x4000;
|
|
#if defined(LZO1Z)
|
|
last_m_off = pd((const uint8_t*)op, m_pos);
|
|
#endif
|
|
#endif /* COPY_DICT */
|
|
}
|
|
else { /* a M1 match */
|
|
#if defined(COPY_DICT)
|
|
#if defined(LZO1Z)
|
|
m_off = 1 + (t << 6) + (*ip++ >> 2);
|
|
last_m_off = m_off;
|
|
#else
|
|
m_off = 1 + (t >> 2) + (*ip++ << 2);
|
|
#endif
|
|
NEED_OP(2);
|
|
t = 2; COPY_DICT(t,m_off)
|
|
#else /* !COPY_DICT */
|
|
#if defined(LZO1Z)
|
|
t = 1 + (t << 6) + (*ip++ >> 2);
|
|
m_pos = op - t;
|
|
last_m_off = t;
|
|
#else
|
|
m_pos = op - 1;
|
|
m_pos -= t >> 2;
|
|
m_pos -= *ip++ << 2;
|
|
#endif
|
|
TEST_LB(m_pos); NEED_OP(2);
|
|
*op++ = *m_pos++;
|
|
*op++ = *m_pos;
|
|
#endif /* COPY_DICT */
|
|
goto match_done;
|
|
}
|
|
|
|
/* copy match */
|
|
#if defined(COPY_DICT)
|
|
|
|
NEED_OP(t+3-1);
|
|
t += 3-1; COPY_DICT(t,m_off)
|
|
|
|
#else /* !COPY_DICT */
|
|
|
|
TEST_LB(m_pos); assert(t > 0); NEED_OP(t+3-1);
|
|
#if defined(LZO_UNALIGNED_OK_4) || defined(LZO_ALIGNED_OK_4)
|
|
# if !defined(LZO_UNALIGNED_OK_4)
|
|
if (t >= 2 * 4 - (3 - 1) && PTR_ALIGNED2_4(op,m_pos)) {
|
|
assert((op - m_pos) >= 4); /* both pointers are aligned */
|
|
# else
|
|
if (t >= 2 * 4 - (3 - 1) && (op - m_pos) >= 4) {
|
|
# endif
|
|
COPY4(op,m_pos);
|
|
op += 4; m_pos += 4; t -= 4 - (3 - 1);
|
|
do {
|
|
COPY4(op,m_pos);
|
|
op += 4; m_pos += 4; t -= 4;
|
|
} while (t >= 4);
|
|
if (t > 0)
|
|
do *op++ = *m_pos++; while (--t > 0);
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
copy_match:
|
|
*op++ = *m_pos++; *op++ = *m_pos++;
|
|
do *op++ = *m_pos++; while (--t > 0);
|
|
}
|
|
|
|
#endif /* COPY_DICT */
|
|
|
|
match_done:
|
|
#if defined(LZO1Z)
|
|
t = ip[-1] & 3;
|
|
#else
|
|
t = ip[-2] & 3;
|
|
#endif
|
|
if (t == 0)
|
|
break;
|
|
|
|
/* copy literals */
|
|
match_next:
|
|
assert(t > 0);
|
|
assert(t < 4);
|
|
NEED_OP(t);
|
|
NEED_IP(t+1);
|
|
#if 0
|
|
do *op++ = *ip++; while (--t > 0);
|
|
#else
|
|
*op++ = *ip++;
|
|
if (t > 1) {
|
|
*op++ = *ip++;
|
|
if (t > 2)
|
|
*op++ = *ip++;
|
|
}
|
|
#endif
|
|
t = *ip++;
|
|
} while (TEST_IP && TEST_OP);
|
|
}
|
|
|
|
//#if defined(HAVE_TEST_IP) || defined(HAVE_TEST_OP)
|
|
/* no EOF code was found */
|
|
*out_len = pd(op, out);
|
|
return LZO_E_EOF_NOT_FOUND;
|
|
//#endif
|
|
|
|
eof_found:
|
|
assert(t == 1);
|
|
*out_len = pd(op, out);
|
|
return (ip == ip_end ? LZO_E_OK :
|
|
(ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
|
|
|
|
//#if defined(HAVE_NEED_IP)
|
|
input_overrun:
|
|
*out_len = pd(op, out);
|
|
return LZO_E_INPUT_OVERRUN;
|
|
//#endif
|
|
|
|
//#if defined(HAVE_NEED_OP)
|
|
output_overrun:
|
|
*out_len = pd(op, out);
|
|
return LZO_E_OUTPUT_OVERRUN;
|
|
//#endif
|
|
|
|
//#if defined(LZO_TEST_OVERRUN_LOOKBEHIND)
|
|
lookbehind_overrun:
|
|
*out_len = pd(op, out);
|
|
return LZO_E_LOOKBEHIND_OVERRUN;
|
|
//#endif
|
|
}
|