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Diffstat (limited to 'lib/zstd/entropy_common.c')
| -rw-r--r-- | lib/zstd/entropy_common.c | 243 |
1 files changed, 0 insertions, 243 deletions
diff --git a/lib/zstd/entropy_common.c b/lib/zstd/entropy_common.c deleted file mode 100644 index 2b0a643c32c4..000000000000 --- a/lib/zstd/entropy_common.c +++ /dev/null @@ -1,243 +0,0 @@ -/* - * Common functions of New Generation Entropy library - * Copyright (C) 2016, 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. - * - * This program is free software; you can redistribute it and/or modify it under - * the terms of the GNU General Public License version 2 as published by the - * Free Software Foundation. This program is dual-licensed; you may select - * either version 2 of the GNU General Public License ("GPL") or BSD license - * ("BSD"). - * - * You can contact the author at : - * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy - */ - -/* ************************************* -* Dependencies -***************************************/ -#include "error_private.h" /* ERR_*, ERROR */ -#include "fse.h" -#include "huf.h" -#include "mem.h" - -/*=== Version ===*/ -unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; } - -/*=== Error Management ===*/ -unsigned FSE_isError(size_t code) { return ERR_isError(code); } - -unsigned HUF_isError(size_t code) { return ERR_isError(code); } - -/*-************************************************************** -* FSE NCount encoding-decoding -****************************************************************/ -size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSVPtr, unsigned *tableLogPtr, const void *headerBuffer, size_t hbSize) -{ - const BYTE *const istart = (const BYTE *)headerBuffer; - const BYTE *const iend = istart + hbSize; - const BYTE *ip = istart; - int nbBits; - int remaining; - int threshold; - U32 bitStream; - int bitCount; - unsigned charnum = 0; - int previous0 = 0; - - if (hbSize < 4) - return ERROR(srcSize_wrong); - bitStream = ZSTD_readLE32(ip); - nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */ - if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) - return ERROR(tableLog_tooLarge); - bitStream >>= 4; - bitCount = 4; - *tableLogPtr = nbBits; - remaining = (1 << nbBits) + 1; - threshold = 1 << nbBits; - nbBits++; - - while ((remaining > 1) & (charnum <= *maxSVPtr)) { - if (previous0) { - unsigned n0 = charnum; - while ((bitStream & 0xFFFF) == 0xFFFF) { - n0 += 24; - if (ip < iend - 5) { - ip += 2; - bitStream = ZSTD_readLE32(ip) >> bitCount; - } else { - bitStream >>= 16; - bitCount += 16; - } - } - while ((bitStream & 3) == 3) { - n0 += 3; - bitStream >>= 2; - bitCount += 2; - } - n0 += bitStream & 3; - bitCount += 2; - if (n0 > *maxSVPtr) - return ERROR(maxSymbolValue_tooSmall); - while (charnum < n0) - normalizedCounter[charnum++] = 0; - if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) { - ip += bitCount >> 3; - bitCount &= 7; - bitStream = ZSTD_readLE32(ip) >> bitCount; - } else { - bitStream >>= 2; - } - } - { - int const max = (2 * threshold - 1) - remaining; - int count; - - if ((bitStream & (threshold - 1)) < (U32)max) { - count = bitStream & (threshold - 1); - bitCount += nbBits - 1; - } else { - count = bitStream & (2 * threshold - 1); - if (count >= threshold) - count -= max; - bitCount += nbBits; - } - - count--; /* extra accuracy */ - remaining -= count < 0 ? -count : count; /* -1 means +1 */ - normalizedCounter[charnum++] = (short)count; - previous0 = !count; - while (remaining < threshold) { - nbBits--; - threshold >>= 1; - } - - if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) { - ip += bitCount >> 3; - bitCount &= 7; - } else { - bitCount -= (int)(8 * (iend - 4 - ip)); - ip = iend - 4; - } - bitStream = ZSTD_readLE32(ip) >> (bitCount & 31); - } - } /* while ((remaining>1) & (charnum<=*maxSVPtr)) */ - if (remaining != 1) - return ERROR(corruption_detected); - if (bitCount > 32) - return ERROR(corruption_detected); - *maxSVPtr = charnum - 1; - - ip += (bitCount + 7) >> 3; - return ip - istart; -} - -/*! HUF_readStats() : - Read compact Huffman tree, saved by HUF_writeCTable(). - `huffWeight` is destination buffer. - `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32. - @return : size read from `src` , or an error Code . - Note : Needed by HUF_readCTable() and HUF_readDTableX?() . -*/ -size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) -{ - U32 weightTotal; - const BYTE *ip = (const BYTE *)src; - size_t iSize; - size_t oSize; - - if (!srcSize) - return ERROR(srcSize_wrong); - iSize = ip[0]; - /* memset(huffWeight, 0, hwSize); */ /* is not necessary, even though some analyzer complain ... */ - - if (iSize >= 128) { /* special header */ - oSize = iSize - 127; - iSize = ((oSize + 1) / 2); - if (iSize + 1 > srcSize) - return ERROR(srcSize_wrong); - if (oSize >= hwSize) - return ERROR(corruption_detected); - ip += 1; - { - U32 n; - for (n = 0; n < oSize; n += 2) { - huffWeight[n] = ip[n / 2] >> 4; - huffWeight[n + 1] = ip[n / 2] & 15; - } - } - } else { /* header compressed with FSE (normal case) */ - if (iSize + 1 > srcSize) - return ERROR(srcSize_wrong); - oSize = FSE_decompress_wksp(huffWeight, hwSize - 1, ip + 1, iSize, 6, workspace, workspaceSize); /* max (hwSize-1) values decoded, as last one is implied */ - if (FSE_isError(oSize)) - return oSize; - } - - /* collect weight stats */ - memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32)); - weightTotal = 0; - { - U32 n; - for (n = 0; n < oSize; n++) { - if (huffWeight[n] >= HUF_TABLELOG_MAX) - return ERROR(corruption_detected); - rankStats[huffWeight[n]]++; - weightTotal += (1 << huffWeight[n]) >> 1; - } - } - if (weightTotal == 0) - return ERROR(corruption_detected); - - /* get last non-null symbol weight (implied, total must be 2^n) */ - { - U32 const tableLog = BIT_highbit32(weightTotal) + 1; - if (tableLog > HUF_TABLELOG_MAX) - return ERROR(corruption_detected); - *tableLogPtr = tableLog; - /* determine last weight */ - { - U32 const total = 1 << tableLog; - U32 const rest = total - weightTotal; - U32 const verif = 1 << BIT_highbit32(rest); - U32 const lastWeight = BIT_highbit32(rest) + 1; - if (verif != rest) - return ERROR(corruption_detected); /* last value must be a clean power of 2 */ - huffWeight[oSize] = (BYTE)lastWeight; - rankStats[lastWeight]++; - } - } - - /* check tree construction validity */ - if ((rankStats[1] < 2) || (rankStats[1] & 1)) - return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */ - - /* results */ - *nbSymbolsPtr = (U32)(oSize + 1); - return iSize + 1; -} |