lz4/lz4.h
yann.collet.73@gmail.com 420248cff4 CLI : added test mode
CLI : corrected writing to NULL within Linux
Minor : several comments were updated

git-svn-id: https://lz4.googlecode.com/svn/trunk@29 650e7d94-2a16-8b24-b05c-7c0b3f6821cd
2011-09-25 21:34:35 +00:00

94 lines
3.9 KiB
C

/*
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 slower than LZ4_uncompress, and is therefore not recommended for general use
*/
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.
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 when repetitively calling the compression algorithm on many small segments.
*/
#if defined (__cplusplus)
}
#endif