summaryrefslogtreecommitdiff
path: root/src/config2a.h
blob: 17c8281d62cc3a614806b3b3abab58b8e44e8805 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
/* config2a.h -- configuration for the LZO2A algorithm

   This file is part of the LZO real-time data compression library.

   Copyright (C) 1996-2015 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/
 */


/* WARNING: this file should *not* be used by applications. It is
   part of the implementation of the library and is subject
   to change.
 */


#ifndef __LZO_CONFIG2A_H
#define __LZO_CONFIG2A_H 1

#include "lzo_conf.h"
#include <lzo/lzo2a.h>


/***********************************************************************
// algorithm configuration
************************************************************************/

/* dictionary depth (0 - 6) - this only affects the compressor.
 * 0 is fastest, 6 is best compression ratio */
#if !defined(DDBITS)
#  define DDBITS    0
#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 (DDBITS < 0 || DDBITS > 6)
#  error "invalid DDBITS"
#endif
#if (CLEVEL < 1 || CLEVEL > 9)
#  error "invalid CLEVEL"
#endif


/***********************************************************************
// internal configuration
************************************************************************/

#if 1
#define SWD_N        8191           /* size of ring buffer */
#else
#define SWD_N       16383           /* size of ring buffer */
#endif

#define M1_MIN_LEN  2
#define M1_MAX_LEN  5
#define M2_MIN_LEN  3
#define M3_MIN_LEN  3


/* add a special code so that the decompressor can detect the
 * end of the compressed data block (overhead is 3 bytes per block) */
#define LZO_EOF_CODE 1

#undef LZO_DETERMINISTIC


/***********************************************************************
// algorithm internal configuration
************************************************************************/

/* choose the hashing strategy */
#ifndef LZO_HASH
#define LZO_HASH        LZO_HASH_LZO_INCREMENTAL_A
#endif

/* config */
#define DD_BITS         DDBITS
#ifndef D_BITS
#define D_BITS          14
#endif



/***********************************************************************
// optimization and debugging
************************************************************************/

/* Collect statistics */
#if 0 && !defined(LZO_COLLECT_STATS)
#  define LZO_COLLECT_STATS 1
#endif


/***********************************************************************
//
************************************************************************/

/* get bits */
#define _NEEDBITS \
    { _NEEDBYTE; b |= ((lzo_uint32_t) _NEXTBYTE) << k; k += 8; assert(k <= 32); }
#define NEEDBITS(j)     { assert((j) < 8); if (k < (j)) _NEEDBITS }

/* set bits */
#define SETBITS(j,x)    { b |= ((lzo_uint32_t)(x)) << k; k += (j); assert(k <= 32); }

/* access bits */
#define MASKBITS(j)     (b & ((((lzo_uint32_t)1 << (j)) - 1)))

/* drop bits */
#define DUMPBITS(j)     { assert(k >= j); b >>= (j); k -= (j); }



#endif /* already included */


/* vim:set ts=4 sw=4 et: */