From 9bcf1e97960c0da7322a868efdbc07e2650716fe Mon Sep 17 00:00:00 2001 From: "Juan J. Martinez" Date: Sat, 9 Jan 2021 09:01:05 +0000 Subject: Extra libs: ap.lib aPLib support with apultra. --- tools/apultra/src/matchfinder.h | 94 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+) create mode 100644 tools/apultra/src/matchfinder.h (limited to 'tools/apultra/src/matchfinder.h') diff --git a/tools/apultra/src/matchfinder.h b/tools/apultra/src/matchfinder.h new file mode 100644 index 0000000..7d68eaf --- /dev/null +++ b/tools/apultra/src/matchfinder.h @@ -0,0 +1,94 @@ +/* + * matchfinder.h - LZ match finder definitions + * + * Copyright (C) 2019 Emmanuel Marty + * + * This software is provided 'as-is', without any express or implied + * warranty. In no event will the authors be held liable for any damages + * arising from the use of this software. + * + * Permission is granted to anyone to use this software for any purpose, + * including commercial applications, and to alter it and redistribute it + * freely, subject to the following restrictions: + * + * 1. The origin of this software must not be misrepresented; you must not + * claim that you wrote the original software. If you use this software + * in a product, an acknowledgment in the product documentation would be + * appreciated but is not required. + * 2. Altered source versions must be plainly marked as such, and must not be + * misrepresented as being the original software. + * 3. This notice may not be removed or altered from any source distribution. + */ + +/* + * Uses the libdivsufsort library Copyright (c) 2003-2008 Yuta Mori + * + * Inspired by cap by Sven-Åke Dahl. https://github.com/svendahl/cap + * Also inspired by Charles Bloom's compression blog. http://cbloomrants.blogspot.com/ + * With ideas from LZ4 by Yann Collet. https://github.com/lz4/lz4 + * With help and support from spke + * + */ + +#ifndef _MATCHFINDER_H +#define _MATCHFINDER_H + +#ifdef __cplusplus +extern "C" { +#endif + +/* Forward declarations */ +typedef struct _apultra_match apultra_match; +typedef struct _apultra_compressor apultra_compressor; + +/** + * Parse input data, build suffix array and overlaid data structures to speed up match finding + * + * @param pCompressor compression context + * @param pInWindow pointer to input data window (previously compressed bytes + bytes to compress) + * @param nInWindowSize total input size in bytes (previously compressed bytes + bytes to compress) + * + * @return 0 for success, non-zero for failure + */ +int apultra_build_suffix_array(apultra_compressor *pCompressor, const unsigned char *pInWindow, const int nInWindowSize); + +/** + * Find matches at the specified offset in the input window + * + * @param pCompressor compression context + * @param nOffset offset to find matches at, in the input window + * @param pMatches pointer to returned matches + * @param pMatchDepth pointer to returned match depths + * @param pMatch1 pointer to 1-byte length, 4 bit offset match + * @param nMaxMatches maximum number of matches to return (0 for none) + * @param nBlockFlags bit 0: 1 for first block, 0 otherwise; bit 1: 1 for last block, 0 otherwise + * + * @return number of matches + */ +int apultra_find_matches_at(apultra_compressor *pCompressor, const int nOffset, apultra_match *pMatches, unsigned short *pMatchDepth, unsigned char *pMatch1, const int nMaxMatches, const int nBlockFlags); + +/** + * Skip previously compressed bytes + * + * @param pCompressor compression context + * @param nStartOffset current offset in input window (typically 0) + * @param nEndOffset offset to skip to in input window (typically the number of previously compressed bytes) + */ +void apultra_skip_matches(apultra_compressor *pCompressor, const int nStartOffset, const int nEndOffset); + +/** + * Find all matches for the data to be compressed + * + * @param pCompressor compression context + * @param nMatchesPerOffset maximum number of matches to store for each offset + * @param nStartOffset current offset in input window (typically the number of previously compressed bytes) + * @param nEndOffset offset to end finding matches at (typically the size of the total input window in bytes + * @param nBlockFlags bit 0: 1 for first block, 0 otherwise; bit 1: 1 for last block, 0 otherwise + */ +void apultra_find_all_matches(apultra_compressor *pCompressor, const int nMatchesPerOffset, const int nStartOffset, const int nEndOffset, const int nBlockFlags); + +#ifdef __cplusplus +} +#endif + +#endif /* _MATCHFINDER_H */ -- cgit v1.2.3