/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright (C) 2004 Patrik Kluba,
* University of Szeged, Hungary
*
* For licensing information, see the file 'LICENCE' in the
* jffs2 directory.
*
* $Id: compr_lzo.c,v 1.3 2004/06/23 16:34:39 havasi Exp $
*
*/
/*
LZO1X-1 (and -999) compression module for jffs2
based on the original LZO sources
*/
/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
/*
Original copyright notice follows:
lzo1x_9x.c -- implementation of the LZO1X-999 compression algorithm
lzo_ptr.h -- low-level pointer constructs
lzo_swd.ch -- sliding window dictionary
lzoconf.h -- configuration for the LZO real-time data compression library
lzo_mchw.ch -- matching functions using a window
minilzo.c -- mini subset of the LZO real-time data compression library
config1x.h -- configuration for the LZO1X algorithm
lzo1x.h -- public interface of the LZO1X compression algorithm
These files are part of the LZO real-time data compression library.
Copyright (C) 1996-2002 Markus Franz Xaver Johannes Oberhumer
All Rights Reserved.
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.,
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Markus F.X.J. Oberhumer
<markus@oberhumer.com>
*/
/*
2004-02-16 pajko <pajko(AT)halom(DOT)u-szeged(DOT)hu>
Initial release
-removed all 16 bit code
-all sensitive data will be on 4 byte boundary
-removed check parts for library use
-removed all but LZO1X-* compression
*/
#include <config.h>
#include <linux/stddef.h>
#include <jffs2/jffs2.h>
#include <jffs2/compr_rubin.h>
/* Integral types that have *exactly* the same number of bits as a lzo_voidp */
typedef unsigned long lzo_ptr_t;
typedef long lzo_sptr_t;
/* data type definitions */
#define U32 unsigned long
#define S32 signed long
#define I32 long
#define U16 unsigned short
#define S16 signed short
#define I16 short
#define U8 unsigned char
#define S8 signed char
#define I8 char
#define M1_MAX_OFFSET 0x0400
#define M2_MAX_OFFSET 0x0800
#define M3_MAX_OFFSET 0x4000
#define M4_MAX_OFFSET 0xbfff
#define __COPY4(dst,src) * (lzo_uint32p)(dst) = * (const lzo_uint32p)(src)
#define COPY4(dst,src) __COPY4((lzo_ptr_t)(dst),(lzo_ptr_t)(src))
#define TEST_IP (ip < ip_end)
#define TEST_OP (op <= op_end)
#define NEED_IP(x) \
if ((lzo_uint)(ip_end - ip) < (lzo_uint)(x)) goto input_overrun
#define NEED_OP(x) \
if ((lzo_uint)(op_end - op) < (lzo_uint)(x)) goto output_overrun
#define TEST_LOOKBEHIND(m_pos,out) if (m_pos < out) goto lookbehind_overrun
typedef U32 lzo_uint32;
typedef I32 lzo_int32;
typedef U32 lzo_uint;
typedef I32 lzo_int;
typedef int lzo_bool;
#define lzo_byte U8
#define lzo_bytep U8 *
#define lzo_charp char *
#define lzo_voidp void *
#define lzo_shortp short *
#define lzo_ushortp unsigned short *
#define lzo_uint32p lzo_uint32 *
#define lzo_int32p lzo_int32 *
#define lzo_uintp lzo_uint *
#define lzo_intp lzo_int *
#define lzo_voidpp lzo_voidp *
#define lzo_bytepp lzo_bytep *
#define lzo_sizeof_dict_t sizeof(lzo_bytep)
#define LZO_E_OK 0
#define LZO_E_ERROR (-1)
#define LZO_E_OUT_OF_MEMORY (-2) /* not used right now */
#define LZO_E_NOT_COMPRESSIBLE (-3) /* not used right now */
#define LZO_E_INPUT_OVERRUN (-4)
#define LZO_E_OUTPUT_OVERRUN (-5)
#define LZO_E_LOOKBEHIND_OVERRUN (-6)
#define LZO_E_EOF_NOT_FOUND (-7)
#define LZO_E_INPUT_NOT_CONSUMED (-8)
#define PTR(a) ((lzo_ptr_t) (a))
#define PTR_LINEAR(a) PTR(a)
#define PTR_ALIGNED_4(a) ((PTR_LINEAR(a) & 3) == 0)
#define PTR_ALIGNED_8(a) ((PTR_LINEAR(a) & 7) == 0)
#define PTR_ALIGNED2_4(a,b) (((PTR_LINEAR(a) | PTR_LINEAR(b)) & 3) == 0)
#define PTR_ALIGNED2_8(a,b) (((PTR_LINEAR(a) | PTR_LINEAR(b)) & 7) == 0)
#define PTR_LT(a,b) (PTR(a) < PTR(b))
#define PTR_GE(a,b) (PTR(a) >= PTR(b))
#define PTR_DIFF(a,b) ((lzo_ptrdiff_t) (PTR(a) - PTR(b)))
#define pd(a,b) ((lzo_uint) ((a)-(b)))
typedef ptrdiff_t lzo_ptrdiff_t;
static int
lzo1x_decompress (const lzo_byte * in, lzo_uint in_len,
lzo_byte * out, lzo_uintp out_len, lzo_voidp wrkmem)
{
register lzo_byte *op;
register const lzo_byte *ip;
register lzo_uint t;
register const lzo_byte *m_pos;
const lzo_byte *const ip_end = in + in_len;
lzo_byte *const op_end = out + *out_len;
*out_len = 0;
op = out;
ip = in;
if (*ip > 17)
{
t = *ip++ - 17;
if (t < 4)
goto match_next;
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;
if (t == 0)
{
NEED_IP (1);
while (*ip == 0)
{
t += 255;
ip++;
NEED_IP (1);
}
t += 15 + *ip++;
}
NEED_OP (t + 3);
NEED_IP (t + 4);
if (PTR_ALIGNED2_4 (op, ip))
{
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);
}
}
else
{
*op++ = *ip++;
*op++ = *ip++;
*op++ = *ip++;
do
*op++ = *ip++;
while (--t > 0);
}
first_literal_run:
t = *ip++;
if (t >= 16)
goto match;
m_pos = op - (1 + M2_MAX_OFFSET);
m_pos -= t >> 2;
m_pos -= *ip++ << 2;
TEST_LOOKBEHIND (m_pos, out);
NEED_OP (3);
*op++ = *m_pos++;
*op++ = *m_pos++;
*op++ = *m_pos;
goto match_done;
while (TEST_IP && TEST_OP)
{
match:
if (t >= 64)
{
m_pos = op - 1;
m_pos -= (t >> 2) & 7;
m_pos -= *ip++ << 3;
t = (t >> 5) - 1;
TEST_LOOKBEHIND (m_pos, out);
NEED_OP (t + 3 - 1);
goto copy_match;
}
else if (t >= 32)
{
t &= 31;
if (t == 0)
{
NEED_IP (1);
while (*ip == 0)
{
t += 255;
ip++;
NEED_IP (1);
}
t += 31 + *ip++;
}
m_pos = op - 1;
m_pos -= (ip[0] >> 2) + (ip[1] << 6);
ip += 2;
}
else if (t >= 16)
{
m_pos = op;
m_pos -= (t & 8) << 11;
t &= 7;
if (t == 0)
{
NEED_IP (1);
while (*ip == 0)
{
t += 255;
ip++;
NEED_IP (1);
}
t += 7 + *ip++;
}
m_pos -= (ip[0] >> 2) + (ip[1] << 6);
ip += 2;
if (m_pos == op)
goto eof_found;
m_pos -= 0x4000;
}
else
{
m_pos = op - 1;
m_pos -= t >> 2;
m_pos -= *ip++ << 2;
TEST_LOOKBEHIND (m_pos, out);
NEED_OP (2);
*op++ = *m_pos++;
*op++ = *m_pos;
goto match_done;
}
TEST_LOOKBEHIND (m_pos, out);
NEED_OP (t + 3 - 1);
if (t >= 2 * 4 - (3 - 1)
&& PTR_ALIGNED2_4 (op, m_pos))
{
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
{
copy_match:
*op++ = *m_pos++;
*op++ = *m_pos++;
do
*op++ = *m_pos++;
while (--t > 0);
}
match_done:
t = ip[-2] & 3;
if (t == 0)
break;
match_next:
NEED_OP (t);
NEED_IP (t + 1);
do
*op++ = *ip++;
while (--t > 0);
t = *ip++;
}
}
*out_len = op - out;
return LZO_E_EOF_NOT_FOUND;
eof_found:
*out_len = op - out;
return (ip == ip_end ? LZO_E_OK :
(ip <
ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
input_overrun:
*out_len = op - out;
return LZO_E_INPUT_OVERRUN;
output_overrun:
*out_len = op - out;
return LZO_E_OUTPUT_OVERRUN;
lookbehind_overrun:
*out_len = op - out;
return LZO_E_LOOKBEHIND_OVERRUN;
}
int lzo_decompress(unsigned char *data_in, unsigned char *cpage_out,
u32 srclen, u32 destlen)
{
lzo_uint outlen = destlen;
return lzo1x_decompress (data_in, srclen, cpage_out, &outlen, NULL);
}