lzo-2.03/src/config2a.h

/* config2a.h -- configuration for the LZO2A algorithm

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

   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/
 */


/* 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

#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 N            8191           /* size of ring buffer */
#else
#define 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

#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
#endif


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

/* get bits */
#define _NEEDBITS \
    { _NEEDBYTE; b |= ((lzo_uint32) _NEXTBYTE) << k; k += 8; assert(k <= 32); }
#define NEEDBITS(j)     { assert((j) < 8); if (k < (j)) _NEEDBITS }

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

/* access bits */
#define MASKBITS(j)     (b & ((((lzo_uint32)1 << (j)) - 1)))

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



#endif /* already included */

/*
vi:ts=4:et
*/