/* lzo1a_de.h -- definitions for the the LZO1A algorithm This file is part of the LZO real-time data compression library. Copyright (C) 1996-2014 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 http://www.oberhumer.com/opensource/lzo/ */ /* WARNING: this file should *not* be used by applications. It is part of the implementation of the LZO package and is subject to change. */ #ifndef __LZO_DEFS_H #define __LZO_DEFS_H 1 #ifdef __cplusplus extern "C" { #endif /*********************************************************************** // ************************************************************************/ /* Format of the marker byte 76543210 -------- 00000000 a long literal run ('R0' run) - there are short and long R0 runs 000rrrrr a short literal 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 MBITS (8 - OBITS) #define MSIZE (1 << MBITS) #define MMASK (MSIZE - 1) #define OBITS RBITS /* offset and run-length use same bits */ #define OSIZE (1 << OBITS) #define OMASK (OSIZE - 1) /* additional bits for coding the length in a long match */ #define LBITS 8 #define LSIZE (1 << LBITS) #define LMASK (LSIZE - 1) /*********************************************************************** // some macros to improve readability ************************************************************************/ /* Minimum len of a match */ #define MIN_MATCH 3 #define THRESHOLD (MIN_MATCH - 1) /* Min-/Maximum len of a match coded in 2 bytes */ #define MIN_MATCH_SHORT (MIN_MATCH) #define MAX_MATCH_SHORT (MIN_MATCH_SHORT + (MSIZE - 2) - 1) /* why (MSIZE - 2) ? because 0 is used to mark runs, * and MSIZE-1 is used to mark a long match */ /* Min-/Maximum len of a match coded in 3 bytes */ #define MIN_MATCH_LONG (MAX_MATCH_SHORT + 1) #define MAX_MATCH_LONG (MIN_MATCH_LONG + LSIZE - 1) /* Min-/Maximum offset of a match */ #define MIN_OFFSET 1 #define MAX_OFFSET (1 << (CHAR_BIT + OBITS)) /* 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 & ~7) /* 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 */ /* 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 */ /*********************************************************************** // ************************************************************************/ #define DBITS 13 #include "lzo_dict.h" #define DVAL_LEN DVAL_LOOKAHEAD #ifdef __cplusplus } /* extern "C" */ #endif #endif /* already included */ /* vi:ts=4:et */