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