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/* |
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* Copyright (c) 2000-2007 Marc Alexander Lehmann <schmorp@schmorp.de> |
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* |
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* Redistribution and use in source and binary forms, with or without modifica- |
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* tion, are permitted provided that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright notice, |
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* this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- |
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* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
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* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- |
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* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
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* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
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* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- |
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* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
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* OF THE POSSIBILITY OF SUCH DAMAGE. |
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* |
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* Alternatively, the contents of this file may be used under the terms of |
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* the GNU General Public License ("GPL") version 2 or any later version, |
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* in which case the provisions of the GPL are applicable instead of |
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* the above. If you wish to allow the use of your version of this file |
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* only under the terms of the GPL and not to allow others to use your |
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* version of this file under the BSD license, indicate your decision |
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* by deleting the provisions above and replace them with the notice |
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* and other provisions required by the GPL. If you do not delete the |
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* provisions above, a recipient may use your version of this file under |
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* either the BSD or the GPL. |
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*/ |
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|
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#ifndef LZFP_h |
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#define LZFP_h |
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|
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#define STANDALONE 1 /* at the moment, this is ok. */ |
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|
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#ifndef STANDALONE |
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# include "lzf.h" |
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#endif |
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|
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/* |
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* Size of hashtable is (1 << HLOG) * sizeof (char *) |
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* decompression is independent of the hash table size |
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* the difference between 15 and 14 is very small |
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* for small blocks (and 14 is usually a bit faster). |
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* For a low-memory/faster configuration, use HLOG == 13; |
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* For best compression, use 15 or 16 (or more, up to 22). |
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*/ |
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#ifndef HLOG |
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# define HLOG 16 |
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#endif |
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|
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/* |
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* Sacrifice very little compression quality in favour of compression speed. |
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* This gives almost the same compression as the default code, and is |
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* (very roughly) 15% faster. This is the preferred mode of operation. |
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*/ |
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#ifndef VERY_FAST |
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# define VERY_FAST 1 |
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#endif |
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|
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/* |
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* Sacrifice some more compression quality in favour of compression speed. |
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* (roughly 1-2% worse compression for large blocks and |
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* 9-10% for small, redundant, blocks and >>20% better speed in both cases) |
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* In short: when in need for speed, enable this for binary data, |
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* possibly disable this for text data. |
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*/ |
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#ifndef ULTRA_FAST |
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# define ULTRA_FAST 0 |
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#endif |
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|
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/* |
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* Unconditionally aligning does not cost very much, so do it if unsure. |
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* Unaligned accesses are not safe even on x86, so disable by default. |
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*/ |
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#ifndef STRICT_ALIGN |
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# define STRICT_ALIGN 0 /* was: # !(defined(__i386) || defined (__amd64)) */ |
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#endif |
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|
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/* |
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* You may choose to pre-set the hash table (might be faster on some |
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* modern cpus and large (>>64k) blocks, and also makes compression |
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* deterministic/repeatable when the configuration otherwise is the same). |
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*/ |
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#ifndef INIT_HTAB |
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# define INIT_HTAB 1 |
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#endif |
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|
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/* |
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* Avoid assigning values to errno variable? for some embedding purposes |
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* (linux kernel for example), this is necessary. NOTE: this breaks |
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* the documentation in lzf.h. Avoiding errno has no speed impact. |
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*/ |
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#ifndef AVOID_ERRNO |
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# define AVOID_ERRNO 0 |
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#endif |
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|
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/* |
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* Whether to pass the LZF_STATE variable as argument, or allocate it |
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* on the stack. For small-stack environments, define this to 1. |
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* NOTE: this breaks the prototype in lzf.h. |
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*/ |
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#ifndef LZF_STATE_ARG |
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# define LZF_STATE_ARG 0 |
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#endif |
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|
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/* |
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* Whether to add extra checks for input validity in lzf_decompress |
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* and return EINVAL if the input stream has been corrupted. This |
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* only shields against overflowing the input buffer and will not |
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* detect most corrupted streams. |
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* This check is not normally noticeable on modern hardware |
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* (<1% slowdown), but might slow down older cpus considerably. |
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*/ |
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#ifndef CHECK_INPUT |
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# define CHECK_INPUT 1 |
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#endif |
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|
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/* |
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* Whether the target CPU has a slow multiplication. This affects |
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* the default hash function for the compressor, and enables a slightly |
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* worse hash function that needs only shifts. |
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*/ |
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#ifndef MULTIPLICATION_IS_SLOW |
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# define MULTIPLICATION_IS_SLOW 0 |
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#endif |
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|
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/* |
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* If defined, then this data type will be used for storing offsets. |
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* This can be useful if you want to use a huge hashtable, want to |
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* conserve memory, or both, and your data fits into e.g. 64kb. |
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* If instead you want to compress data > 4GB, then it's better to |
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* to "#define LZF_USE_OFFSETS 0" instead. |
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*/ |
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/*#define LZF_HSLOT unsigned short*/ |
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|
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/* |
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* Whether to store pointers or offsets inside the hash table. On |
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* 64 bit architetcures, pointers take up twice as much space, |
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* and might also be slower. Default is to autodetect. |
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*/ |
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/*#define LZF_USE_OFFSETS autodetect */ |
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|
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/* |
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* Whether to optimise code for size, at the expense of speed. Use |
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* this when you are extremely tight on memory, perhaps in combination |
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* with AVOID_ERRNO 1 and CHECK_INPUT 0. |
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*/ |
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#ifndef OPTIMISE_SIZE |
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# ifdef __OPTIMIZE_SIZE__ |
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# define OPTIMISE_SIZE 1 |
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# else |
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# define OPTIMISE_SIZE 0 |
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# endif |
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#endif |
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|
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/*****************************************************************************/ |
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/* nothing should be changed below */ |
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|
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#ifdef __cplusplus |
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# include <cstring> |
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# include <climits> |
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using namespace std; |
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#else |
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# include <string.h> |
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# include <limits.h> |
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#endif |
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|
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#if ULTRA_FAST |
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# undef VERY_FAST |
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#endif |
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|
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#ifndef LZF_USE_OFFSETS |
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# ifdef _WIN32 |
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# define LZF_USE_OFFSETS defined(_M_X64) |
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# else |
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# if __cplusplus > 199711L |
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# include <cstdint> |
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# else |
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# include <stdint.h> |
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# endif |
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# define LZF_USE_OFFSETS (UINTPTR_MAX > 0xffffffffU) |
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# endif |
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#endif |
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|
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typedef unsigned char u8; |
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|
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#ifdef LZF_HSLOT |
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# define LZF_HSLOT_BIAS ((const u8 *)in_data) |
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#else |
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# if LZF_USE_OFFSETS |
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# define LZF_HSLOT_BIAS ((const u8 *)in_data) |
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typedef unsigned int LZF_HSLOT; |
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# else |
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# define LZF_HSLOT_BIAS 0 |
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typedef const u8 *LZF_HSLOT; |
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# endif |
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#endif |
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|
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#if USHRT_MAX == 65535 |
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typedef unsigned short u16; |
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#elif UINT_MAX == 65535 |
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typedef unsigned int u16; |
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#else |
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# undef STRICT_ALIGN |
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# define STRICT_ALIGN 1 |
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#endif |
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|
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#define LZF_MAX_LIT (1 << 5) |
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#define LZF_MAX_OFF (1 << 13) |
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#define LZF_MAX_REF ((1 << 8) + (1 << 3)) |
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|
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typedef LZF_HSLOT LZF_STATE[1 << (HLOG)]; |
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|
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typedef struct |
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{ |
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const u8 *first [1 << (6+8)]; /* most recent occurance of a match */ |
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u16 prev [LZF_MAX_OFF]; /* how many bytes to go backwards for the next match */ |
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} LZF_STATE_BEST[1]; |
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|
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#endif |
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|