cpukit/libdl/fastlz.h

0001 /*
0002   FastLZ - lightning-fast lossless compression library
0003
0004   Copyright (C) 2007 Ariya Hidayat (ariya@kde.org)
0005   Copyright (C) 2006 Ariya Hidayat (ariya@kde.org)
0006   Copyright (C) 2005 Ariya Hidayat (ariya@kde.org)
0007
0008   Permission is hereby granted, free of charge, to any person obtaining a copy
0009   of this software and associated documentation files (the "Software"), to deal
0010   in the Software without restriction, including without limitation the rights
0011   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
0012   copies of the Software, and to permit persons to whom the Software is
0013   furnished to do so, subject to the following conditions:
0014
0015   The above copyright notice and this permission notice shall be included in
0016   all copies or substantial portions of the Software.
0017
0018   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
0019   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
0020   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
0021   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
0022   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
0023   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
0024   THE SOFTWARE.
0025 */
0026
0027 #ifndef FASTLZ_H
0028 #define FASTLZ_H
0029
0030 #define FASTLZ_VERSION 0x000100
0031
0032 #define FASTLZ_VERSION_MAJOR     0
0033 #define FASTLZ_VERSION_MINOR     0
0034 #define FASTLZ_VERSION_REVISION  0
0035
0036 #define FASTLZ_VERSION_STRING "0.1.0"
0037
0038 #if defined (__cplusplus)
0039 extern "C" {
0040 #endif
0041
0042 /**
0043   Compress a block of data in the input buffer and returns the size of
0044   compressed block. The size of input buffer is specified by length. The
0045   minimum input buffer size is 16.
0046
0047   The output buffer must be at least 5% larger than the input buffer
0048   and can not be smaller than 66 bytes.
0049
0050   If the input is not compressible, the return value might be larger than
0051   length (input buffer size).
0052
0053   The input buffer and the output buffer can not overlap.
0054 */
0055
0056 int fastlz_compress(const void* input, int length, void* output);
0057
0058 /**
0059   Decompress a block of compressed data and returns the size of the
0060   decompressed block. If error occurs, e.g. the compressed data is
0061   corrupted or the output buffer is not large enough, then 0 (zero)
0062   will be returned instead.
0063
0064   The input buffer and the output buffer can not overlap.
0065
0066   Decompression is memory safe and guaranteed not to write the output buffer
0067   more than what is specified in maxout.
0068  */
0069
0070 int fastlz_decompress(const void* input, int length, void* output, int maxout);
0071
0072 /**
0073   Compress a block of data in the input buffer and returns the size of
0074   compressed block. The size of input buffer is specified by length. The
0075   minimum input buffer size is 16.
0076
0077   The output buffer must be at least 5% larger than the input buffer
0078   and can not be smaller than 66 bytes.
0079
0080   If the input is not compressible, the return value might be larger than
0081   length (input buffer size).
0082
0083   The input buffer and the output buffer can not overlap.
0084
0085   Compression level can be specified in parameter level. At the moment,
0086   only level 1 and level 2 are supported.
0087   Level 1 is the fastest compression and generally useful for short data.
0088   Level 2 is slightly slower but it gives better compression ratio.
0089
0090   Note that the compressed data, regardless of the level, can always be
0091   decompressed using the function fastlz_decompress above.
0092 */
0093
0094 int fastlz_compress_level(int level, const void* input, int length, void* output);
0095
0096 #if defined (__cplusplus)
0097 }
0098 #endif
0099
0100 #endif /* FASTLZ_H */