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Diffstat (limited to 'lzo/src/lzo1.c')
| -rw-r--r-- | lzo/src/lzo1.c | 638 |
1 files changed, 0 insertions, 638 deletions
diff --git a/lzo/src/lzo1.c b/lzo/src/lzo1.c deleted file mode 100644 index edf1c3af..00000000 --- a/lzo/src/lzo1.c +++ /dev/null @@ -1,638 +0,0 @@ -/* lzo1.c -- implementation of the LZO1 algorithm - - This file is part of the LZO real-time data compression library. - - Copyright (C) 2011 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2010 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2009 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer - Copyright (C) 1996 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., - 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. - - Markus F.X.J. Oberhumer - <markus@oberhumer.com> - http://www.oberhumer.com/opensource/lzo/ - */ - - -#include "lzo_conf.h" -#include "lzo/lzo1.h" - - -/*********************************************************************** -// The next two defines can be changed to customize LZO1. -// The default version is LZO1-5/1. -************************************************************************/ - -/* run bits (3 - 5) - the compressor and the decompressor - * must use the same value. */ -#if !defined(RBITS) -# define RBITS 5 -#endif - -/* compression level (1 - 9) - this only affects the compressor. - * 1 is fastest, 9 is best compression ratio */ -#if !defined(CLEVEL) -# define CLEVEL 1 /* fastest by default */ -#endif - - -/* check configuration */ -#if (RBITS < 3 || RBITS > 5) -# error "invalid RBITS" -#endif -#if (CLEVEL < 1 || CLEVEL > 9) -# error "invalid CLEVEL" -#endif - - -/*********************************************************************** -// You should not have to change anything below this line. -************************************************************************/ - -/* - Format of the marker byte - - - 76543210 - -------- - 00000000 a long run (a 'R0' run) - there are short and long R0 runs - 000rrrrr a short run with len r - mmmooooo a short match (len = 2+m, o = offset low bits) - 111ooooo a long match (o = offset low bits) -*/ - - -#define RSIZE (1 << RBITS) -#define RMASK (RSIZE - 1) - -#define OBITS RBITS /* offset and run-length use same bits */ -#define OSIZE (1 << OBITS) -#define OMASK (OSIZE - 1) - -#define MBITS (8 - OBITS) -#define MSIZE (1 << MBITS) -#define MMASK (MSIZE - 1) - - -/* sanity checks */ -#if (OBITS < 3 || OBITS > 5) -# error "invalid OBITS" -#endif -#if (MBITS < 3 || MBITS > 5) -# error "invalid MBITS" -#endif - - -/*********************************************************************** -// some macros to improve readability -************************************************************************/ - -/* Minimum len of a match */ -#define MIN_MATCH 3 -#define THRESHOLD (MIN_MATCH - 1) - -/* Minimum len of match coded in 2 bytes */ -#define MIN_MATCH_SHORT MIN_MATCH - -/* Maximum len of match coded in 2 bytes */ -#define MAX_MATCH_SHORT (THRESHOLD + (MSIZE - 2)) -/* MSIZE - 2: 0 is used to indicate runs, - * MSIZE-1 is used to indicate a long match */ - -/* Minimum len of match coded in 3 bytes */ -#define MIN_MATCH_LONG (MAX_MATCH_SHORT + 1) - -/* Maximum len of match coded in 3 bytes */ -#define MAX_MATCH_LONG (MIN_MATCH_LONG + 255) - -/* Maximum offset of a match */ -#define MAX_OFFSET (1 << (8 + OBITS)) - - -/* - -RBITS | MBITS MIN THR. MSIZE MAXS MINL MAXL MAXO R0MAX R0FAST -======+=============================================================== - 3 | 5 3 2 32 32 33 288 2048 263 256 - 4 | 4 3 2 16 16 17 272 4096 271 264 - 5 | 3 3 2 8 8 9 264 8192 287 280 - - */ - - -/*********************************************************************** -// internal configuration -// all of these affect compression only -************************************************************************/ - -/* choose the hashing strategy */ -#ifndef LZO_HASH -#define LZO_HASH LZO_HASH_LZO_INCREMENTAL_A -#endif -#define D_INDEX1(d,p) d = DM(DMUL(0x21,DX2(p,5,5)) >> 5) -#define D_INDEX2(d,p) d = d ^ D_MASK - -#define DBITS (8 + RBITS) -#include "lzo_dict.h" -#define DVAL_LEN DVAL_LOOKAHEAD - - -/*********************************************************************** -// get algorithm info, return memory required for compression -************************************************************************/ - -LZO_EXTERN(lzo_uint) lzo1_info ( int *rbits, int *clevel ); - -LZO_PUBLIC(lzo_uint) -lzo1_info ( int *rbits, int *clevel ) -{ - if (rbits) - *rbits = RBITS; - if (clevel) - *clevel = CLEVEL; - return D_SIZE * lzo_sizeof(lzo_bytep); -} - - -/*********************************************************************** -// decode a R0 literal run (a long run) -************************************************************************/ - -#define R0MIN (RSIZE) /* Minimum len of R0 run of literals */ -#define R0MAX (R0MIN + 255) /* Maximum len of R0 run of literals */ -#define R0FAST (R0MAX & ~7u) /* R0MAX aligned to 8 byte boundary */ - -#if (R0MAX - R0FAST != 7) || ((R0FAST & 7) != 0) -# error "something went wrong" -#endif - -/* 7 special codes from R0FAST+1 .. R0MAX - * these codes mean long R0 runs with lengths - * 512, 1024, 2048, 4096, 8192, 16384, 32768 */ - - -/*********************************************************************** -// LZO1 decompress a block of data. -// -// Could be easily translated into assembly code. -************************************************************************/ - -LZO_PUBLIC(int) -lzo1_decompress ( const lzo_bytep in , lzo_uint in_len, - lzo_bytep out, lzo_uintp out_len, - lzo_voidp wrkmem ) -{ - lzo_bytep op; - const lzo_bytep ip; - const lzo_bytep const ip_end = in + in_len; - lzo_uint t; - - LZO_UNUSED(wrkmem); - - op = out; - ip = in; - while (ip < ip_end) - { - t = *ip++; /* get marker */ - - if (t < R0MIN) /* a literal run */ - { - if (t == 0) /* a R0 literal run */ - { - t = *ip++; - if (t >= R0FAST - R0MIN) /* a long R0 run */ - { - t -= R0FAST - R0MIN; - if (t == 0) - t = R0FAST; - else - { -#if 0 - t = 256u << ((unsigned) t); -#else - /* help the optimizer */ - lzo_uint tt = 256; - do tt <<= 1; while (--t > 0); - t = tt; -#endif - } - MEMCPY8_DS(op,ip,t); - continue; - } - t += R0MIN; - } - MEMCPY_DS(op,ip,t); - } - else /* a match */ - { - lzo_uint tt; - /* get match offset */ - const lzo_bytep m_pos = op - 1; - m_pos -= (lzo_uint)(t & OMASK) | (((lzo_uint) *ip++) << OBITS); - - /* get match len */ - if (t >= ((MSIZE - 1) << OBITS)) /* all m-bits set */ - tt = (MIN_MATCH_LONG - THRESHOLD) + *ip++; /* a long match */ - else - tt = t >> OBITS; /* a short match */ - - assert(m_pos >= out); - assert(m_pos < op); - /* a half unrolled loop */ - *op++ = *m_pos++; - *op++ = *m_pos++; - MEMCPY_DS(op,m_pos,tt); - } - } - - *out_len = pd(op, out); - - /* the next line is the only check in the decompressor ! */ - return (ip == ip_end ? LZO_E_OK : - (ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN)); -} - - -/*********************************************************************** -// code a literal run -************************************************************************/ - -static -#if LZO_ARCH_AVR -__lzo_noinline -#endif -lzo_bytep -store_run(lzo_bytep op, const lzo_bytep ii, lzo_uint r_len) -{ - assert(r_len > 0); - - /* code a long R0 run */ - if (r_len >= 512) - { - unsigned r_bits = 7; /* 256 << 7 == 32768 */ - do { - while (r_len >= (256u << r_bits)) - { - r_len -= (256u << r_bits); - *op++ = 0; *op++ = LZO_BYTE((R0FAST - R0MIN) + r_bits); - MEMCPY8_DS(op, ii, (256u << r_bits)); - } - } while (--r_bits > 0); - } - while (r_len >= R0FAST) - { - r_len -= R0FAST; - *op++ = 0; *op++ = R0FAST - R0MIN; - MEMCPY8_DS(op, ii, R0FAST); - } - - if (r_len >= R0MIN) - { - /* code a short R0 run */ - *op++ = 0; *op++ = LZO_BYTE(r_len - R0MIN); - MEMCPY_DS(op, ii, r_len); - } - else if (r_len > 0) - { - /* code a 'normal' run */ - *op++ = LZO_BYTE(r_len); - MEMCPY_DS(op, ii, r_len); - } - - assert(r_len == 0); - return op; -} - - - -/*********************************************************************** -// LZO1 compress a block of data. -// -// Could be translated into assembly code without too much effort. -// -// I apologize for the spaghetti code, but it really helps the optimizer. -************************************************************************/ - -static int -do_compress ( const lzo_bytep in , lzo_uint in_len, - lzo_bytep out, lzo_uintp out_len, - lzo_voidp wrkmem ) -{ - const lzo_bytep ip; -#if defined(__LZO_HASH_INCREMENTAL) - lzo_xint dv; -#endif - lzo_bytep op; - const lzo_bytep m_pos; - const lzo_bytep const ip_end = in+in_len - DVAL_LEN - MIN_MATCH_LONG; - const lzo_bytep const in_end = in+in_len - DVAL_LEN; - const lzo_bytep ii; - lzo_dict_p const dict = (lzo_dict_p) wrkmem; - -#if !defined(NDEBUG) - const lzo_bytep m_pos_sav; -#endif - - op = out; - ip = in; - ii = ip; /* point to start of literal run */ - if (in_len <= MIN_MATCH_LONG + DVAL_LEN + 1) - goto the_end; - - /* init dictionary */ -#if (LZO_DETERMINISTIC) - BZERO8_PTR(wrkmem,sizeof(lzo_dict_t),D_SIZE); -#endif - - DVAL_FIRST(dv,ip); - UPDATE_D(dict,0,dv,ip,in); - ip++; - DVAL_NEXT(dv,ip); - - do { - LZO_DEFINE_UNINITIALIZED_VAR(lzo_uint, m_off, 0); - lzo_uint dindex; - - DINDEX1(dindex,ip); - GINDEX(m_pos,m_off,dict,dindex,in); - if (LZO_CHECK_MPOS(m_pos,m_off,in,ip,MAX_OFFSET)) - goto literal; - if (m_pos[0] == ip[0] && m_pos[1] == ip[1] && m_pos[2] == ip[2]) - goto match; - DINDEX2(dindex,ip); - GINDEX(m_pos,m_off,dict,dindex,in); - if (LZO_CHECK_MPOS(m_pos,m_off,in,ip,MAX_OFFSET)) - goto literal; - if (m_pos[0] == ip[0] && m_pos[1] == ip[1] && m_pos[2] == ip[2]) - goto match; - goto literal; - - -literal: - UPDATE_I(dict,0,dindex,ip,in); - if (++ip >= ip_end) - break; - continue; - -match: - UPDATE_I(dict,0,dindex,ip,in); -#if !defined(NDEBUG) && (LZO_DICT_USE_PTR) - m_pos_sav = m_pos; -#endif - m_pos += 3; - { - /* we have found a match (of at least length 3) */ -#if !defined(NDEBUG) && !(LZO_DICT_USE_PTR) - assert((m_pos_sav = ip - m_off) == (m_pos - 3)); -#endif - /* 1) store the current literal run */ - if (pd(ip,ii) > 0) - { - lzo_uint t = pd(ip,ii); -#if 1 - /* OPTIMIZED: inline the copying of a short run */ - if (t < R0MIN) - { - *op++ = LZO_BYTE(t); - MEMCPY_DS(op, ii, t); - } - else -#endif - op = store_run(op,ii,t); - } - - /* 2a) compute match len */ - ii = ip; /* point to start of current match */ - - /* we already matched MIN_MATCH bytes, - * m_pos also already advanced MIN_MATCH bytes */ - ip += MIN_MATCH; - assert(m_pos < ip); - - /* try to match another MIN_MATCH_LONG - MIN_MATCH bytes - * to see if we get a long match */ - -#define PS *m_pos++ != *ip++ - -#if (MIN_MATCH_LONG - MIN_MATCH == 2) /* MBITS == 2 */ - if (PS || PS) -#elif (MIN_MATCH_LONG - MIN_MATCH == 6) /* MBITS == 3 */ - if (PS || PS || PS || PS || PS || PS) -#elif (MIN_MATCH_LONG - MIN_MATCH == 14) /* MBITS == 4 */ - if (PS || PS || PS || PS || PS || PS || PS || - PS || PS || PS || PS || PS || PS || PS) -#elif (MIN_MATCH_LONG - MIN_MATCH == 30) /* MBITS == 5 */ - if (PS || PS || PS || PS || PS || PS || PS || PS || - PS || PS || PS || PS || PS || PS || PS || PS || - PS || PS || PS || PS || PS || PS || PS || PS || - PS || PS || PS || PS || PS || PS) -#else -# error "MBITS not yet implemented" -#endif - { - lzo_uint m_len; - - /* 2b) code a short match */ - assert(pd(ip,m_pos) == m_off); - --ip; /* ran one too far, point back to non-match */ - m_len = pd(ip, ii); - assert(m_len >= MIN_MATCH_SHORT); - assert(m_len <= MAX_MATCH_SHORT); - assert(m_off > 0); - assert(m_off <= MAX_OFFSET); - assert(ii-m_off == m_pos_sav); - assert(lzo_memcmp(m_pos_sav,ii,m_len) == 0); - --m_off; - /* code short match len + low offset bits */ - *op++ = LZO_BYTE(((m_len - THRESHOLD) << OBITS) | - (m_off & OMASK)); - /* code high offset bits */ - *op++ = LZO_BYTE(m_off >> OBITS); - - - /* 2c) Insert phrases (beginning with ii+1) into the dictionary. */ - -#define SI /* nothing */ -#define DI ++ii; DVAL_NEXT(dv,ii); UPDATE_D(dict,0,dv,ii,in); -#define XI assert(ii < ip); ii = ip; DVAL_FIRST(dv,(ip)); - -#if (CLEVEL == 9) || (CLEVEL >= 7 && MBITS <= 4) || (CLEVEL >= 5 && MBITS <= 3) - /* Insert the whole match (ii+1)..(ip-1) into dictionary. */ - ++ii; - do { - DVAL_NEXT(dv,ii); - UPDATE_D(dict,0,dv,ii,in); - } while (++ii < ip); - DVAL_NEXT(dv,ii); - assert(ii == ip); - DVAL_ASSERT(dv,ip); -#elif (CLEVEL >= 3) - SI DI DI XI -#elif (CLEVEL >= 2) - SI DI XI -#else - XI -#endif - - } - else - { - /* we've found a long match - see how far we can still go */ - const lzo_bytep end; - lzo_uint m_len; - - assert(ip <= in_end); - assert(ii == ip - MIN_MATCH_LONG); - - if (pd(in_end,ip) <= (MAX_MATCH_LONG - MIN_MATCH_LONG)) - end = in_end; - else - { - end = ip + (MAX_MATCH_LONG - MIN_MATCH_LONG); - assert(end < in_end); - } - - while (ip < end && *m_pos == *ip) - m_pos++, ip++; - assert(ip <= in_end); - - /* 2b) code the long match */ - m_len = pd(ip, ii); - assert(m_len >= MIN_MATCH_LONG); - assert(m_len <= MAX_MATCH_LONG); - assert(m_off > 0); - assert(m_off <= MAX_OFFSET); - assert(ii-m_off == m_pos_sav); - assert(lzo_memcmp(m_pos_sav,ii,m_len) == 0); - assert(pd(ip,m_pos) == m_off); - --m_off; - /* code long match flag + low offset bits */ - *op++ = LZO_BYTE(((MSIZE - 1) << OBITS) | (m_off & OMASK)); - /* code high offset bits */ - *op++ = LZO_BYTE(m_off >> OBITS); - /* code match len */ - *op++ = LZO_BYTE(m_len - MIN_MATCH_LONG); - - - /* 2c) Insert phrases (beginning with ii+1) into the dictionary. */ -#if (CLEVEL == 9) - /* Insert the whole match (ii+1)..(ip-1) into dictionary. */ - /* This is not recommended because it is slow. */ - ++ii; - do { - DVAL_NEXT(dv,ii); - UPDATE_D(dict,0,dv,ii,in); - } while (++ii < ip); - DVAL_NEXT(dv,ii); - assert(ii == ip); - DVAL_ASSERT(dv,ip); -#elif (CLEVEL >= 8) - SI DI DI DI DI DI DI DI DI XI -#elif (CLEVEL >= 7) - SI DI DI DI DI DI DI DI XI -#elif (CLEVEL >= 6) - SI DI DI DI DI DI DI XI -#elif (CLEVEL >= 5) - SI DI DI DI DI XI -#elif (CLEVEL >= 4) - SI DI DI DI XI -#elif (CLEVEL >= 3) - SI DI DI XI -#elif (CLEVEL >= 2) - SI DI XI -#else - XI -#endif - } - - /* ii now points to the start of next literal run */ - assert(ii == ip); - } - } while (ip < ip_end); - - - -the_end: - assert(ip <= in_end); - - -#if defined(LZO_RETURN_IF_NOT_COMPRESSIBLE) - /* return -1 if op == out to indicate that we - * couldn't compress and didn't copy anything. - */ - if (op == out) - { - *out_len = 0; - return LZO_E_NOT_COMPRESSIBLE; - } -#endif - - - /* store the final literal run */ - if (pd(in_end+DVAL_LEN,ii) > 0) - op = store_run(op,ii,pd(in_end+DVAL_LEN,ii)); - - *out_len = pd(op, out); - return 0; /* compression went ok */ -} - - -/*********************************************************************** -// compress public entry point. -************************************************************************/ - -LZO_PUBLIC(int) -lzo1_compress ( const lzo_bytep in , lzo_uint in_len, - lzo_bytep out, lzo_uintp out_len, - lzo_voidp wrkmem ) -{ - int r = LZO_E_OK; - - /* don't try to compress a block that's too short */ - if (in_len == 0) - *out_len = 0; - else if (in_len <= MIN_MATCH_LONG + DVAL_LEN + 1) - { -#if defined(LZO_RETURN_IF_NOT_COMPRESSIBLE) - r = LZO_E_NOT_COMPRESSIBLE; -#else - *out_len = pd(store_run(out,in,in_len), out); -#endif - } - else - r = do_compress(in,in_len,out,out_len,wrkmem); - - return r; -} - - -/* -vi:ts=4:et -*/ |