--- liblzf/lzfP.h 2007/11/02 12:39:20 1.16 +++ liblzf/lzfP.h 2015/06/29 23:34:41 1.31 @@ -1,16 +1,16 @@ /* * Copyright (c) 2000-2007 Marc Alexander Lehmann - * + * * Redistribution and use in source and binary forms, with or without modifica- * tion, are permitted provided that the following conditions are met: - * + * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. - * + * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. - * + * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO @@ -23,14 +23,15 @@ * OF THE POSSIBILITY OF SUCH DAMAGE. * * Alternatively, the contents of this file may be used under the terms of - * the GNU General Public License version 2 (the "GPL"), in which case the - * provisions of the GPL are applicable instead of the above. If you wish to - * allow the use of your version of this file only under the terms of the - * GPL and not to allow others to use your version of this file under the - * BSD license, indicate your decision by deleting the provisions above and - * replace them with the notice and other provisions required by the GPL. If - * you do not delete the provisions above, a recipient may use your version - * of this file under either the BSD or the GPL. + * the GNU General Public License ("GPL") version 2 or any later version, + * in which case the provisions of the GPL are applicable instead of + * the above. If you wish to allow the use of your version of this file + * only under the terms of the GPL and not to allow others to use your + * version of this file under the BSD license, indicate your decision + * by deleting the provisions above and replace them with the notice + * and other provisions required by the GPL. If you do not delete the + * provisions above, a recipient may use your version of this file under + * either the BSD or the GPL. */ #ifndef LZFP_h @@ -48,18 +49,17 @@ * the difference between 15 and 14 is very small * for small blocks (and 14 is usually a bit faster). * For a low-memory/faster configuration, use HLOG == 13; - * For best compression, use 15 or 16 (or more). + * For best compression, use 15 or 16 (or more, up to 22). */ #ifndef HLOG -# define HLOG 15 +# define HLOG 16 #endif /* * Sacrifice very little compression quality in favour of compression speed. * This gives almost the same compression as the default code, and is - * (very roughly) 15% faster. This is the preferable mode of operation. + * (very roughly) 15% faster. This is the preferred mode of operation. */ - #ifndef VERY_FAST # define VERY_FAST 1 #endif @@ -88,20 +88,20 @@ * deterministic/repeatable when the configuration otherwise is the same). */ #ifndef INIT_HTAB -# define INIT_HTAB 0 +# define INIT_HTAB 1 #endif /* * Avoid assigning values to errno variable? for some embedding purposes - * (linux kernel for example), this is neccessary. NOTE: this breaks - * the documentation in lzf.h. + * (linux kernel for example), this is necessary. NOTE: this breaks + * the documentation in lzf.h. Avoiding errno has no speed impact. */ #ifndef AVOID_ERRNO # define AVOID_ERRNO 0 #endif /* - * Wether to pass the LZF_STATE variable as argument, or allocate it + * Whether to pass the LZF_STATE variable as argument, or allocate it * on the stack. For small-stack environments, define this to 1. * NOTE: this breaks the prototype in lzf.h. */ @@ -110,50 +110,118 @@ #endif /* - * Wether to add extra checks for input validity in lzf_decompress + * Whether to add extra checks for input validity in lzf_decompress * and return EINVAL if the input stream has been corrupted. This * only shields against overflowing the input buffer and will not * detect most corrupted streams. - * This check is not normally noticable on modern hardware + * This check is not normally noticeable on modern hardware * (<1% slowdown), but might slow down older cpus considerably. */ #ifndef CHECK_INPUT # define CHECK_INPUT 1 #endif -/*****************************************************************************/ -/* nothing should be changed below */ +/* + * Whether the target CPU has a slow multiplication. This affects + * the default hash function for the compressor, and enables a slightly + * worse hash function that needs only shifts. + */ +#ifndef MULTIPLICATION_IS_SLOW +# define MULTIPLICATION_IS_SLOW 0 +#endif -typedef unsigned char u8; +/* + * If defined, then this data type will be used for storing offsets. + * This can be useful if you want to use a huge hashtable, want to + * conserve memory, or both, and your data fits into e.g. 64kb. + * If instead you want to compress data > 4GB, then it's better to + * to "#define LZF_USE_OFFSETS 0" instead. + */ +/*#define LZF_HSLOT unsigned short*/ -typedef const u8 *LZF_STATE[1 << (HLOG)]; +/* + * Whether to store pointers or offsets inside the hash table. On + * 64 bit architetcures, pointers take up twice as much space, + * and might also be slower. Default is to autodetect. + */ +/*#define LZF_USE_OFFSETS autodetect */ -#if !STRICT_ALIGN -/* for unaligned accesses we need a 16 bit datatype. */ -# include -# if USHRT_MAX == 65535 - typedef unsigned short u16; -# elif UINT_MAX == 65535 - typedef unsigned int u16; +/* + * Whether to optimise code for size, at the expense of speed. Use + * this when you are extremely tight on memory, perhaps in combination + * with AVOID_ERRNO 1 and CHECK_INPUT 0. + */ +#ifndef OPTIMISE_SIZE +# ifdef __OPTIMIZE_SIZE__ +# define OPTIMISE_SIZE 1 # else -# undef STRICT_ALIGN -# define STRICT_ALIGN 1 +# define OPTIMISE_SIZE 0 # endif #endif +/*****************************************************************************/ +/* nothing should be changed below */ + +#ifdef __cplusplus +# include +# include +using namespace std; +#else +# include +# include +#endif + #if ULTRA_FAST -# if defined(VERY_FAST) -# undef VERY_FAST +# undef VERY_FAST +#endif + +#ifndef LZF_USE_OFFSETS +# ifdef _WIN32 +# define LZF_USE_OFFSETS defined(_M_X64) +# else +# if __cplusplus > 199711L +# include +# else +# include +# endif +# define LZF_USE_OFFSETS (UINTPTR_MAX > 0xffffffffU) # endif #endif -#if INIT_HTAB -# ifdef __cplusplus -# include +typedef unsigned char u8; + +#ifdef LZF_HSLOT +# define LZF_HSLOT_BIAS ((const u8 *)in_data) +#else +# if LZF_USE_OFFSETS +# define LZF_HSLOT_BIAS ((const u8 *)in_data) + typedef unsigned int LZF_HSLOT; # else -# include +# define LZF_HSLOT_BIAS 0 + typedef const u8 *LZF_HSLOT; # endif #endif +#if USHRT_MAX == 65535 + typedef unsigned short u16; +#elif UINT_MAX == 65535 + typedef unsigned int u16; +#else +# undef STRICT_ALIGN +# define STRICT_ALIGN 1 +#endif + +#define LZF_MAX_LIT (1 << 5) +#define LZF_MAX_OFF (1 << 13) +#define LZF_MAX_REF ((1 << 8) + (1 << 3)) + +typedef LZF_HSLOT LZF_STATE[1 << (HLOG)]; + +typedef struct +{ + const u8 *first [1 << (6+8)]; /* most recent occurance of a match */ + u16 prev [LZF_MAX_OFF]; /* how many bytes to go backwards for the next match */ +} LZF_STATE_BEST[1]; + #endif