/* | |
LZ4 - Fast LZ compression algorithm | |
Header File | |
Copyright (C) 2011-2013, Yann Collet. | |
BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) | |
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. | |
You can contact the author at : | |
- LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html | |
- LZ4 source repository : http://code.google.com/p/lz4/ | |
*/ | |
#pragma once | |
#if defined (__cplusplus) | |
extern "C" { | |
#endif | |
//************************************** | |
// Compiler Options | |
//************************************** | |
#if defined(_MSC_VER) && !defined(__cplusplus) // Visual Studio | |
# define inline __inline // Visual C is not C99, but supports some kind of inline | |
#endif | |
//**************************** | |
// Simple Functions | |
//**************************** | |
int LZ4_compress (const char* source, char* dest, int inputSize); | |
int LZ4_decompress_safe (const char* source, char* dest, int inputSize, int maxOutputSize); | |
/* | |
LZ4_compress() : | |
Compresses 'inputSize' bytes from 'source' into 'dest'. | |
Destination buffer must be already allocated, | |
and must be sized to handle worst cases situations (input data not compressible) | |
Worst case size evaluation is provided by function LZ4_compressBound() | |
inputSize : Max supported value is ~1.9GB | |
return : the number of bytes written in buffer dest | |
or 0 if the compression fails | |
LZ4_decompress_safe() : | |
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 detected malformed, the function will stop decoding and return a negative result. | |
This function is protected against buffer overflow exploits (never writes outside of output buffer, and never reads outside of input buffer). Therefore, it is protected against malicious data packets | |
*/ | |
//**************************** | |
// Advanced Functions | |
//**************************** | |
static inline int LZ4_compressBound(int isize) { return ((isize) + ((isize)/255) + 16); } | |
#define LZ4_COMPRESSBOUND( isize) ((isize) + ((isize)/255) + 16) | |
/* | |
LZ4_compressBound() : | |
Provides the maximum size that LZ4 may output in a "worst case" scenario (input data not compressible) | |
primarily useful for memory allocation of output buffer. | |
inline function is recommended for the general case, | |
macro is also provided when result needs to be evaluated at compilation (such as table size allocation). | |
isize : is the input size. Max supported value is ~1.9GB | |
return : maximum output size in a "worst case" scenario | |
note : this function is limited by "int" range (2^31-1) | |
*/ | |
int LZ4_compress_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize); | |
/* | |
LZ4_compress_limitedOutput() : | |
Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'. | |
If it cannot achieve it, compression will stop, and result of the function will be zero. | |
This function never writes outside of provided output buffer. | |
inputSize : Max supported value is ~1.9GB | |
maxOutputSize : is the size of the destination buffer (which must be already allocated) | |
return : the number of bytes written in buffer 'dest' | |
or 0 if the compression fails | |
*/ | |
int LZ4_decompress_fast (const char* source, char* dest, int outputSize); | |
/* | |
LZ4_decompress_fast() : | |
outputSize : is the original (uncompressed) size | |
return : the number of bytes read from the source buffer (in other words, the compressed size) | |
If the source stream is malformed, the function will stop decoding and return a negative result. | |
note : This function is a bit faster than LZ4_decompress_safe() | |
This function never writes outside of output buffers, but may read beyond input buffer in case of malicious data packet. | |
Use this function preferably into a trusted environment (data to decode comes from a trusted source). | |
Destination buffer must be already allocated. Its size must be a minimum of 'outputSize' bytes. | |
*/ | |
int LZ4_decompress_safe_partial (const char* source, char* dest, int inputSize, int targetOutputSize, int maxOutputSize); | |
/* | |
LZ4_decompress_safe_partial() : | |
This function decompress a compressed block of size 'inputSize' at position 'source' | |
into output buffer 'dest' of size 'maxOutputSize'. | |
The function stops decompressing operation as soon as 'targetOutputSize' has been reached, | |
reducing decompression time. | |
return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize) | |
Note : this number can be < 'targetOutputSize' should the compressed block to decode be smaller. | |
Always control how many bytes were decoded. | |
If the source stream is malformed, the function will stop decoding and return a negative result. | |
This function never writes outside of output buffer, and never reads outside of input buffer. It is therefore protected against malicious data packets | |
*/ | |
int LZ4_decompress_safe_withPrefix64k (const char* source, char* dest, int inputSize, int maxOutputSize); | |
int LZ4_decompress_fast_withPrefix64k (const char* source, char* dest, int outputSize); | |
/* | |
*_withPrefix64k() : | |
These decoding functions work the same as their "normal name" versions, | |
but will potentially use up to 64KB of data in front of 'char* dest'. | |
These functions are used for decoding inter-dependant blocks. | |
*/ | |
//**************************** | |
// Obsolete Functions | |
//**************************** | |
static inline int LZ4_uncompress (const char* source, char* dest, int outputSize) { return LZ4_decompress_fast(source, dest, outputSize); } | |
static inline int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) { return LZ4_decompress_safe(source, dest, isize, maxOutputSize); } | |
/* | |
These functions are deprecated and should no longer be used. | |
They are provided here for compatibility with existing user programs. | |
*/ | |
#if defined (__cplusplus) | |
} | |
#endif |