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/* |
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* Copyright (c) 2000-2008 Marc Alexander Lehmann <schmorp@schmorp.de> |
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* |
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* Redistribution and use in source and binary forms, with or without modifica- |
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* tion, are permitted provided that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright notice, |
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* this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- |
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* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
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* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- |
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* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
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* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
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* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- |
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* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
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* OF THE POSSIBILITY OF SUCH DAMAGE. |
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* |
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* Alternatively, the contents of this file may be used under the terms of |
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* the GNU General Public License ("GPL") version 2 or any later version, |
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* in which case the provisions of the GPL are applicable instead of |
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* the above. If you wish to allow the use of your version of this file |
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* only under the terms of the GPL and not to allow others to use your |
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* version of this file under the BSD license, indicate your decision |
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* by deleting the provisions above and replace them with the notice |
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* and other provisions required by the GPL. If you do not delete the |
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* provisions above, a recipient may use your version of this file under |
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* either the BSD or the GPL. |
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*/ |
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|
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#ifndef LZF_H |
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#define LZF_H |
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|
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/*********************************************************************** |
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** |
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** lzf -- an extremely fast/free compression/decompression-method |
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** http://liblzf.plan9.de/ |
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** |
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** This algorithm is believed to be patent-free. |
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** |
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***********************************************************************/ |
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|
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/* API version (major * 256 + minor) |
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* major API version gets bumped on incompatible changes. |
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* minor API version gets bumped on compatible changes. |
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* 1.5 => 1.6: add LZF_MAX_COMPRESSED_SIZE |
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*/ |
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#define LZF_VERSION 0x0106 |
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|
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/* |
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* Compress in_len bytes stored at the memory block starting at |
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* in_data and write the result to out_data, up to a maximum length |
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* of out_len bytes. |
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* |
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* If the output buffer is not large enough or any error occurs return 0, |
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* otherwise return the number of bytes used, which might be considerably |
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* more than in_len (but less than 1 + 104% of the original size), so it |
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* makes sense to always use out_len == in_len - 1), to ensure _some_ |
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* compression, and store the data uncompressed otherwise (with a flag, of |
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* course. |
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* |
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* lzf_compress might use different algorithms on different systems and |
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* even different runs, thus might result in different compressed strings |
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* depending on the phase of the moon or similar factors. However, all |
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* these strings are architecture-independent and will result in the |
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* original data when decompressed using lzf_decompress. |
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* |
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* The buffers must not be overlapping. |
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* |
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* If the option LZF_STATE_ARG is enabled, an extra argument must be |
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* supplied which is not reflected in this header file. Refer to lzfP.h |
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* and lzf_c.c. |
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* |
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*/ |
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unsigned int |
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lzf_compress (const void *const in_data, unsigned int in_len, |
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void *out_data, unsigned int out_len); |
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|
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/* |
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* The maximum out_len that needs to be allocated to make sure |
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* any input data can be compressed without overflowing the output |
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* buffer, i.e. maximum out_len = LZF_MAX_COMPRESSED_SIZE (in_len). |
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* This is useful if you don't want to bother with the case of |
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* incompressible data and just want to provide a buffer that is |
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* guaranteeed to be big enough. |
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* This macro can be used at preprocessing time. |
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*/ |
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#define LZF_MAX_COMPRESSED_SIZE(n) ((((n) * 33) >> 5 ) + 1) |
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|
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/* |
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* Decompress data compressed with some version of the lzf_compress |
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* function and stored at location in_data and length in_len. The result |
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* will be stored at out_data up to a maximum of out_len characters. |
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* |
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* If the output buffer is not large enough to hold the decompressed |
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* data, a 0 is returned and errno is set to E2BIG. Otherwise the number |
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* of decompressed bytes (i.e. the original length of the data) is |
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* returned. |
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* |
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* If an error in the compressed data is detected, a zero is returned and |
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* errno is set to EINVAL. |
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* |
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* This function is very fast, about as fast as a copying loop. |
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*/ |
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unsigned int |
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lzf_decompress (const void *const in_data, unsigned int in_len, |
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void *out_data, unsigned int out_len); |
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|
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#endif |
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|