release/src/router/lzo/src/config2a.h

   1 /* config2a.h -- configuration for the LZO2A algorithm
   2
   3    This file is part of the LZO real-time data compression library.
   4
   5    Copyright (C) 2011 Markus Franz Xaver Johannes Oberhumer
   6    Copyright (C) 2010 Markus Franz Xaver Johannes Oberhumer
   7    Copyright (C) 2009 Markus Franz Xaver Johannes Oberhumer
   8    Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
   9    Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
  10    Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
  11    Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
  12    Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
  13    Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
  14    Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
  15    Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
  16    Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
  17    Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
  18    Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
  19    Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
  20    Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
  21    All Rights Reserved.
  22
  23    The LZO library is free software; you can redistribute it and/or
  24    modify it under the terms of the GNU General Public License as
  25    published by the Free Software Foundation; either version 2 of
  26    the License, or (at your option) any later version.
  27
  28    The LZO library is distributed in the hope that it will be useful,
  29    but WITHOUT ANY WARRANTY; without even the implied warranty of
  30    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  31    GNU General Public License for more details.
  32
  33    You should have received a copy of the GNU General Public License
  34    along with the LZO library; see the file COPYING.
  35    If not, write to the Free Software Foundation, Inc.,
  36    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  37
  38    Markus F.X.J. Oberhumer
  39    <markus@oberhumer.com>
  40    http://www.oberhumer.com/opensource/lzo/
  41  */
  42
  43
  44 /* WARNING: this file should *not* be used by applications. It is
  45    part of the implementation of the library and is subject
  46    to change.
  47  */
  48
  49
  50 #ifndef __LZO_CONFIG2A_H
  51 #define __LZO_CONFIG2A_H 1
  52
  53 #include "lzo_conf.h"
  54 #include "lzo/lzo2a.h"
  55
  56
  57 /***********************************************************************
  58 // algorithm configuration
  59 ************************************************************************/
  60
  61 /* dictionary depth (0 - 6) - this only affects the compressor.
  62  * 0 is fastest, 6 is best compression ratio */
  63 #if !defined(DDBITS)
  64 #  define DDBITS    0
  65 #endif
  66
  67 /* compression level (1 - 9) - this only affects the compressor.
  68  * 1 is fastest, 9 is best compression ratio */
  69 #if !defined(CLEVEL)
  70 #  define CLEVEL    1           /* fastest by default */
  71 #endif
  72
  73
  74 /* check configuration */
  75 #if (DDBITS < 0 || DDBITS > 6)
  76 #  error "invalid DDBITS"
  77 #endif
  78 #if (CLEVEL < 1 || CLEVEL > 9)
  79 #  error "invalid CLEVEL"
  80 #endif
  81
  82
  83 /***********************************************************************
  84 // internal configuration
  85 ************************************************************************/
  86
  87 #if 1
  88 #define SWD_N        8191           /* size of ring buffer */
  89 #else
  90 #define SWD_N       16383           /* size of ring buffer */
  91 #endif
  92
  93 #define M1_MIN_LEN  2
  94 #define M1_MAX_LEN  5
  95 #define M2_MIN_LEN  3
  96 #define M3_MIN_LEN  3
  97
  98
  99 /* add a special code so that the decompressor can detect the
 100  * end of the compressed data block (overhead is 3 bytes per block) */
 101 #define LZO_EOF_CODE 1
 102
 103 #undef LZO_DETERMINISTIC
 104
 105
 106 /***********************************************************************
 107 // algorithm internal configuration
 108 ************************************************************************/
 109
 110 /* choose the hashing strategy */
 111 #ifndef LZO_HASH
 112 #define LZO_HASH        LZO_HASH_LZO_INCREMENTAL_A
 113 #endif
 114
 115 /* config */
 116 #define DD_BITS         DDBITS
 117 #ifndef D_BITS
 118 #define D_BITS          14
 119 #endif
 120
 121
 122
 123 /***********************************************************************
 124 // optimization and debugging
 125 ************************************************************************/
 126
 127 /* Collect statistics */
 128 #if 0 && !defined(LZO_COLLECT_STATS)
 129 #  define LZO_COLLECT_STATS 1
 130 #endif
 131
 132
 133 /***********************************************************************
 134 //
 135 ************************************************************************/
 136
 137 /* get bits */
 138 #define _NEEDBITS \
 139     { _NEEDBYTE; b |= ((lzo_uint32) _NEXTBYTE) << k; k += 8; assert(k <= 32); }
 140 #define NEEDBITS(j)     { assert((j) < 8); if (k < (j)) _NEEDBITS }
 141
 142 /* set bits */
 143 #define SETBITS(j,x)    { b |= (x) << k; k += (j); assert(k <= 32); }
 144
 145 /* access bits */
 146 #define MASKBITS(j)     (b & ((((lzo_uint32)1 << (j)) - 1)))
 147
 148 /* drop bits */
 149 #define DUMPBITS(j)     { assert(k >= j); b >>= (j); k -= (j); }
 150
 151
 152
 153 #endif /* already included */
 154
 155 /*
 156 vi:ts=4:et
 157 */
 158