/* | |
LZ4 - Fast LZ compression algorithm | |
Header File | |
Copyright (C) 2011, Yann Collet. | |
BSD License | |
Redistribution and use in source and binary forms, with or without | |
modification, are permitted provided that the following conditions are | |
met: | |
* Redistributions of source code must retain the above copyright | |
notice, this list of conditions and the following disclaimer. | |
* 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 COPYRIGHT HOLDERS AND CONTRIBUTORS | |
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | |
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | |
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | |
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | |
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
*/ | |
#if defined (__cplusplus) | |
extern "C" { | |
#endif | |
//**************************** | |
// Simple Functions | |
//**************************** | |
int LZ4_compress (char* source, char* dest, int isize); | |
int LZ4_uncompress (char* source, char* dest, int osize); | |
/* | |
LZ4_compress() : | |
return : the number of bytes in compressed buffer dest | |
note : destination buffer must be already allocated. | |
To avoid any problem, size it to handle worst cases situations (input data not compressible) | |
Worst case size is : "inputsize + 0.4%", with "0.4%" being at least 8 bytes. | |
LZ4_uncompress() : | |
osize : is the output size, therefore the original size | |
return : the number of bytes read in the source buffer | |
If the source stream is malformed, the function will stop decoding and return a negative result, indicating the byte position of the faulty instruction | |
This version never writes beyond dest + osize, and is therefore protected against malicious data packets | |
note 2 : destination buffer must be already allocated | |
*/ | |
//**************************** | |
// Advanced Functions | |
//**************************** | |
int LZ4_uncompress_unknownOutputSize (char* source, char* dest, int isize, int maxOutputSize); | |
/* | |
LZ4_uncompress_unknownOutputSize() : | |
isize : is the input size, therefore the compressed size | |
maxOutputSize : is the size of the destination buffer (which must be already allocated) | |
return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize) | |
If the source stream is malformed, the function will stop decoding and return a negative result, indicating the byte position of the faulty instruction | |
This version never writes beyond dest + maxOutputSize, and is therefore protected against malicious data packets | |
note : This version is a bit slower than LZ4_uncompress | |
*/ | |
int LZ4_compressCtx(void** ctx, char* source, char* dest, int isize); | |
/* | |
LZ4_compressCtx() : | |
This function explicitly handles the CTX memory structure. | |
It avoids allocating/deallocating memory between each call, improving performance when malloc is time-consuming. | |
Note : when memory is allocated into the stack (default mode), there is no "malloc" penalty. | |
Therefore, this function is mostly useful when memory is allocated into the heap (it requires increasing HASH_LOG value beyond STACK_LIMIT) | |
On first call : provide a *ctx=NULL; It will be automatically allocated. | |
On next calls : reuse the same ctx pointer. | |
Use different pointers for different threads when doing multi-threading. | |
note : performance difference is small, mostly noticeable in HeapMode when repetitively calling the compression function over many small segments. | |
*/ | |
#if defined (__cplusplus) | |
} | |
#endif |