|
1 | | -/* |
2 | | - LZ4 HC - High Compression Mode of LZ4 |
3 | | - Header File |
4 | | - Copyright (C) 2011-2012, Yann Collet. |
5 | | - BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) |
6 | | -
|
7 | | - Redistribution and use in source and binary forms, with or without |
8 | | - modification, are permitted provided that the following conditions are |
9 | | - met: |
10 | | -
|
11 | | - * Redistributions of source code must retain the above copyright |
12 | | - notice, this list of conditions and the following disclaimer. |
13 | | - * Redistributions in binary form must reproduce the above |
14 | | - copyright notice, this list of conditions and the following disclaimer |
15 | | - in the documentation and/or other materials provided with the |
16 | | - distribution. |
17 | | -
|
18 | | - THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
19 | | - "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
20 | | - LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
21 | | - A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
22 | | - OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
23 | | - SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
24 | | - LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
25 | | - DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
26 | | - THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
27 | | - (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
28 | | - OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
29 | | -
|
30 | | - You can contact the author at : |
31 | | - - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html |
32 | | - - LZ4 source repository : http://code.google.com/p/lz4/ |
33 | | -*/ |
34 | | -#pragma once |
35 | | - |
36 | | - |
37 | | -#if defined (__cplusplus) |
38 | | -extern "C" { |
39 | | -#endif |
40 | | - |
41 | | - |
42 | | -int LZ4_compressHC (const char* source, char* dest, int isize); |
43 | | - |
44 | | -/* |
45 | | -LZ4_compressHC : |
46 | | - return : the number of bytes in compressed buffer dest |
47 | | - note : destination buffer must be already allocated. |
48 | | - To avoid any problem, size it to handle worst cases situations (input data not compressible) |
49 | | - Worst case size evaluation is provided by function LZ4_compressBound() (see "lz4.h") |
50 | | -*/ |
51 | | - |
52 | | - |
53 | | -/* Note : |
54 | | -Decompression functions are provided within regular LZ4 source code (see "lz4.h") (BSD license) |
55 | | -*/ |
56 | | - |
57 | | - |
58 | | -#if defined (__cplusplus) |
59 | | -} |
60 | | -#endif |
| 1 | +/* |
| 2 | + LZ4 HC - High Compression Mode of LZ4 |
| 3 | + Header File |
| 4 | + Copyright (C) 2011-2014, Yann Collet. |
| 5 | + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) |
| 6 | +
|
| 7 | + Redistribution and use in source and binary forms, with or without |
| 8 | + modification, are permitted provided that the following conditions are |
| 9 | + met: |
| 10 | +
|
| 11 | + * Redistributions of source code must retain the above copyright |
| 12 | + notice, this list of conditions and the following disclaimer. |
| 13 | + * Redistributions in binary form must reproduce the above |
| 14 | + copyright notice, this list of conditions and the following disclaimer |
| 15 | + in the documentation and/or other materials provided with the |
| 16 | + distribution. |
| 17 | +
|
| 18 | + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 19 | + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 20 | + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 21 | + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 22 | + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 23 | + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 24 | + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 25 | + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 26 | + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 27 | + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 28 | + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 29 | +
|
| 30 | + You can contact the author at : |
| 31 | + - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html |
| 32 | + - LZ4 source repository : http://code.google.com/p/lz4/ |
| 33 | +*/ |
| 34 | +#pragma once |
| 35 | + |
| 36 | + |
| 37 | +#if defined (__cplusplus) |
| 38 | +extern "C" { |
| 39 | +#endif |
| 40 | + |
| 41 | + |
| 42 | +int LZ4_compressHC (const char* source, char* dest, int inputSize); |
| 43 | +/* |
| 44 | +LZ4_compressHC : |
| 45 | + return : the number of bytes in compressed buffer dest |
| 46 | + or 0 if compression fails. |
| 47 | + note : destination buffer must be already allocated. |
| 48 | + To avoid any problem, size it to handle worst cases situations (input data not compressible) |
| 49 | + Worst case size evaluation is provided by function LZ4_compressBound() (see "lz4.h") |
| 50 | +*/ |
| 51 | + |
| 52 | +int LZ4_compressHC_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize); |
| 53 | +/* |
| 54 | +LZ4_compress_limitedOutput() : |
| 55 | + Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'. |
| 56 | + If it cannot achieve it, compression will stop, and result of the function will be zero. |
| 57 | + This function never writes outside of provided output buffer. |
| 58 | +
|
| 59 | + inputSize : Max supported value is 1 GB |
| 60 | + maxOutputSize : is maximum allowed size into the destination buffer (which must be already allocated) |
| 61 | + return : the number of output bytes written in buffer 'dest' |
| 62 | + or 0 if compression fails. |
| 63 | +*/ |
| 64 | + |
| 65 | + |
| 66 | +int LZ4_compressHC2 (const char* source, char* dest, int inputSize, int compressionLevel); |
| 67 | +int LZ4_compressHC2_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel); |
| 68 | +/* |
| 69 | + Same functions as above, but with programmable 'compressionLevel'. |
| 70 | + Recommended values are between 4 and 9, although any value between 0 and 16 will work. |
| 71 | + 'compressionLevel'==0 means use default 'compressionLevel' value. |
| 72 | + Values above 16 behave the same as 16. |
| 73 | + Equivalent variants exist for all other compression functions below. |
| 74 | +*/ |
| 75 | + |
| 76 | +/* Note : |
| 77 | +Decompression functions are provided within LZ4 source code (see "lz4.h") (BSD license) |
| 78 | +*/ |
| 79 | + |
| 80 | + |
| 81 | +/************************************** |
| 82 | + Using an external allocation |
| 83 | +**************************************/ |
| 84 | +int LZ4_sizeofStateHC(void); |
| 85 | +int LZ4_compressHC_withStateHC (void* state, const char* source, char* dest, int inputSize); |
| 86 | +int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize); |
| 87 | + |
| 88 | +int LZ4_compressHC2_withStateHC (void* state, const char* source, char* dest, int inputSize, int compressionLevel); |
| 89 | +int LZ4_compressHC2_limitedOutput_withStateHC(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel); |
| 90 | + |
| 91 | +/* |
| 92 | +These functions are provided should you prefer to allocate memory for compression tables with your own allocation methods. |
| 93 | +To know how much memory must be allocated for the compression tables, use : |
| 94 | +int LZ4_sizeofStateHC(); |
| 95 | +
|
| 96 | +Note that tables must be aligned for pointer (32 or 64 bits), otherwise compression will fail (return code 0). |
| 97 | +
|
| 98 | +The allocated memory can be provided to the compressions functions using 'void* state' parameter. |
| 99 | +LZ4_compress_withStateHC() and LZ4_compress_limitedOutput_withStateHC() are equivalent to previously described functions. |
| 100 | +They just use the externally allocated memory area instead of allocating their own (on stack, or on heap). |
| 101 | +*/ |
| 102 | + |
| 103 | + |
| 104 | +/************************************** |
| 105 | + Streaming Functions |
| 106 | +**************************************/ |
| 107 | +/* Note : these streaming functions still follows the older model */ |
| 108 | +void* LZ4_createHC (const char* inputBuffer); |
| 109 | +int LZ4_compressHC_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize); |
| 110 | +int LZ4_compressHC_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize); |
| 111 | +char* LZ4_slideInputBufferHC (void* LZ4HC_Data); |
| 112 | +int LZ4_freeHC (void* LZ4HC_Data); |
| 113 | + |
| 114 | +int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel); |
| 115 | +int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel); |
| 116 | + |
| 117 | +/* |
| 118 | +These functions allow the compression of dependent blocks, where each block benefits from prior 64 KB within preceding blocks. |
| 119 | +In order to achieve this, it is necessary to start creating the LZ4HC Data Structure, thanks to the function : |
| 120 | +
|
| 121 | +void* LZ4_createHC (const char* inputBuffer); |
| 122 | +The result of the function is the (void*) pointer on the LZ4HC Data Structure. |
| 123 | +This pointer will be needed in all other functions. |
| 124 | +If the pointer returned is NULL, then the allocation has failed, and compression must be aborted. |
| 125 | +The only parameter 'const char* inputBuffer' must, obviously, point at the beginning of input buffer. |
| 126 | +The input buffer must be already allocated, and size at least 192KB. |
| 127 | +'inputBuffer' will also be the 'const char* source' of the first block. |
| 128 | +
|
| 129 | +All blocks are expected to lay next to each other within the input buffer, starting from 'inputBuffer'. |
| 130 | +To compress each block, use either LZ4_compressHC_continue() or LZ4_compressHC_limitedOutput_continue(). |
| 131 | +Their behavior are identical to LZ4_compressHC() or LZ4_compressHC_limitedOutput(), |
| 132 | +but require the LZ4HC Data Structure as their first argument, and check that each block starts right after the previous one. |
| 133 | +If next block does not begin immediately after the previous one, the compression will fail (return 0). |
| 134 | +
|
| 135 | +When it's no longer possible to lay the next block after the previous one (not enough space left into input buffer), a call to : |
| 136 | +char* LZ4_slideInputBufferHC(void* LZ4HC_Data); |
| 137 | +must be performed. It will typically copy the latest 64KB of input at the beginning of input buffer. |
| 138 | +Note that, for this function to work properly, minimum size of an input buffer must be 192KB. |
| 139 | +==> The memory position where the next input data block must start is provided as the result of the function. |
| 140 | +
|
| 141 | +Compression can then resume, using LZ4_compressHC_continue() or LZ4_compressHC_limitedOutput_continue(), as usual. |
| 142 | +
|
| 143 | +When compression is completed, a call to LZ4_freeHC() will release the memory used by the LZ4HC Data Structure. |
| 144 | +*/ |
| 145 | + |
| 146 | +int LZ4_sizeofStreamStateHC(void); |
| 147 | +int LZ4_resetStreamStateHC(void* state, const char* inputBuffer); |
| 148 | + |
| 149 | +/* |
| 150 | +These functions achieve the same result as : |
| 151 | +void* LZ4_createHC (const char* inputBuffer); |
| 152 | +
|
| 153 | +They are provided here to allow the user program to allocate memory using its own routines. |
| 154 | +
|
| 155 | +To know how much space must be allocated, use LZ4_sizeofStreamStateHC(); |
| 156 | +Note also that space must be aligned for pointers (32 or 64 bits). |
| 157 | +
|
| 158 | +Once space is allocated, you must initialize it using : LZ4_resetStreamStateHC(void* state, const char* inputBuffer); |
| 159 | +void* state is a pointer to the space allocated. |
| 160 | +It must be aligned for pointers (32 or 64 bits), and be large enough. |
| 161 | +The parameter 'const char* inputBuffer' must, obviously, point at the beginning of input buffer. |
| 162 | +The input buffer must be already allocated, and size at least 192KB. |
| 163 | +'inputBuffer' will also be the 'const char* source' of the first block. |
| 164 | +
|
| 165 | +The same space can be re-used multiple times, just by initializing it each time with LZ4_resetStreamState(). |
| 166 | +return value of LZ4_resetStreamStateHC() must be 0 is OK. |
| 167 | +Any other value means there was an error (typically, state is not aligned for pointers (32 or 64 bits)). |
| 168 | +*/ |
| 169 | + |
| 170 | + |
| 171 | +#if defined (__cplusplus) |
| 172 | +} |
| 173 | +#endif |
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