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-rw-r--r--vendor/github.com/DataDog/zstd/entropy_common.c236
1 files changed, 0 insertions, 236 deletions
diff --git a/vendor/github.com/DataDog/zstd/entropy_common.c b/vendor/github.com/DataDog/zstd/entropy_common.c
deleted file mode 100644
index b12944e1d..000000000
--- a/vendor/github.com/DataDog/zstd/entropy_common.c
+++ /dev/null
@@ -1,236 +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.
-
- You can contact the author at :
- - FSE+HUF source repository : https://github.com/Cyan4973/FiniteStateEntropy
- - Public forum : https://groups.google.com/forum/#!forum/lz4c
-*************************************************************************** */
-
-/* *************************************
-* Dependencies
-***************************************/
-#include "mem.h"
-#include "error_private.h" /* ERR_*, ERROR */
-#define FSE_STATIC_LINKING_ONLY /* FSE_MIN_TABLELOG */
-#include "fse.h"
-#define HUF_STATIC_LINKING_ONLY /* HUF_TABLELOG_ABSOLUTEMAX */
-#include "huf.h"
-
-
-/*=== Version ===*/
-unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; }
-
-
-/*=== Error Management ===*/
-unsigned FSE_isError(size_t code) { return ERR_isError(code); }
-const char* FSE_getErrorName(size_t code) { return ERR_getErrorName(code); }
-
-unsigned HUF_isError(size_t code) { return ERR_isError(code); }
-const char* HUF_getErrorName(size_t code) { return ERR_getErrorName(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) {
- /* This function only works when hbSize >= 4 */
- char buffer[4];
- memset(buffer, 0, sizeof(buffer));
- memcpy(buffer, headerBuffer, hbSize);
- { size_t const countSize = FSE_readNCount(normalizedCounter, maxSVPtr, tableLogPtr,
- buffer, sizeof(buffer));
- if (FSE_isError(countSize)) return countSize;
- if (countSize > hbSize) return ERROR(corruption_detected);
- return countSize;
- } }
- assert(hbSize >= 4);
-
- /* init */
- memset(normalizedCounter, 0, (*maxSVPtr+1) * sizeof(normalizedCounter[0])); /* all symbols not present in NCount have a frequency of 0 */
- bitStream = MEM_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 = MEM_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)) {
- assert((bitCount >> 3) <= 3); /* For first condition to work */
- ip += bitCount>>3;
- bitCount &= 7;
- bitStream = MEM_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 = MEM_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(BYTE* huffWeight, size_t hwSize, U32* rankStats,
- U32* nbSymbolsPtr, U32* tableLogPtr,
- const void* src, size_t srcSize)
-{
- 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) */
- FSE_DTable fseWorkspace[FSE_DTABLE_SIZE_U32(6)]; /* 6 is max possible tableLog for HUF header (maybe even 5, to be tested) */
- if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
- oSize = FSE_decompress_wksp(huffWeight, hwSize-1, ip+1, iSize, fseWorkspace, 6); /* 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;
-}
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