mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-24 08:32:02 +00:00
561 lines
22 KiB
C
561 lines
22 KiB
C
/* ******************************************************************
|
|
Huffman encoder, part of New Generation Entropy library
|
|
Copyright (C) 2013-2016, 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
|
|
****************************************************************** */
|
|
|
|
/* **************************************************************
|
|
* Compiler specifics
|
|
****************************************************************/
|
|
#if defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
|
|
/* inline is defined */
|
|
#elif defined(_MSC_VER)
|
|
# define inline __inline
|
|
#else
|
|
# define inline /* disable inline */
|
|
#endif
|
|
|
|
|
|
#ifdef _MSC_VER /* Visual Studio */
|
|
# define FORCE_INLINE static __forceinline
|
|
# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
|
|
#else
|
|
# ifdef __GNUC__
|
|
# define FORCE_INLINE static inline __attribute__((always_inline))
|
|
# else
|
|
# define FORCE_INLINE static inline
|
|
# endif
|
|
#endif
|
|
|
|
|
|
/* **************************************************************
|
|
* Includes
|
|
****************************************************************/
|
|
#include <stdlib.h> /* malloc, free, qsort */
|
|
#include <string.h> /* memcpy, memset */
|
|
#include <stdio.h> /* printf (debug) */
|
|
#include "huf_static.h"
|
|
#include "bitstream.h"
|
|
#include "fse.h" /* header compression */
|
|
|
|
|
|
/* **************************************************************
|
|
* Error Management
|
|
****************************************************************/
|
|
#define HUF_STATIC_ASSERT(c) { enum { HUF_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
|
|
|
|
|
|
/* *******************************************************
|
|
* HUF : Huffman block compression
|
|
*********************************************************/
|
|
struct HUF_CElt_s {
|
|
U16 val;
|
|
BYTE nbBits;
|
|
}; /* typedef'd to HUF_CElt within huf_static.h */
|
|
|
|
typedef struct nodeElt_s {
|
|
U32 count;
|
|
U16 parent;
|
|
BYTE byte;
|
|
BYTE nbBits;
|
|
} nodeElt;
|
|
|
|
/*! HUF_writeCTable() :
|
|
`CTable` : huffman tree to save, using huf representation.
|
|
@return : size of saved CTable */
|
|
size_t HUF_writeCTable (void* dst, size_t maxDstSize,
|
|
const HUF_CElt* CTable, U32 maxSymbolValue, U32 huffLog)
|
|
{
|
|
BYTE bitsToWeight[HUF_MAX_TABLELOG + 1];
|
|
BYTE huffWeight[HUF_MAX_SYMBOL_VALUE + 1];
|
|
U32 n;
|
|
BYTE* op = (BYTE*)dst;
|
|
size_t size;
|
|
|
|
/* check conditions */
|
|
if (maxSymbolValue > HUF_MAX_SYMBOL_VALUE + 1)
|
|
return ERROR(GENERIC);
|
|
|
|
/* convert to weight */
|
|
bitsToWeight[0] = 0;
|
|
for (n=1; n<=huffLog; n++)
|
|
bitsToWeight[n] = (BYTE)(huffLog + 1 - n);
|
|
for (n=0; n<maxSymbolValue; n++)
|
|
huffWeight[n] = bitsToWeight[CTable[n].nbBits];
|
|
|
|
size = FSE_compress(op+1, maxDstSize-1, huffWeight, maxSymbolValue); /* don't need last symbol stat : implied */
|
|
if (HUF_isError(size)) return size;
|
|
if (size >= 128) return ERROR(GENERIC); /* should never happen, since maxSymbolValue <= 255 */
|
|
if ((size <= 1) || (size >= maxSymbolValue/2)) {
|
|
if (size==1) { /* RLE */
|
|
/* only possible case : serie of 1 (because there are at least 2) */
|
|
/* can only be 2^n or (2^n-1), otherwise not an huffman tree */
|
|
BYTE code;
|
|
switch(maxSymbolValue)
|
|
{
|
|
case 1: code = 0; break;
|
|
case 2: code = 1; break;
|
|
case 3: code = 2; break;
|
|
case 4: code = 3; break;
|
|
case 7: code = 4; break;
|
|
case 8: code = 5; break;
|
|
case 15: code = 6; break;
|
|
case 16: code = 7; break;
|
|
case 31: code = 8; break;
|
|
case 32: code = 9; break;
|
|
case 63: code = 10; break;
|
|
case 64: code = 11; break;
|
|
case 127: code = 12; break;
|
|
case 128: code = 13; break;
|
|
default : return ERROR(corruption_detected);
|
|
}
|
|
op[0] = (BYTE)(255-13 + code);
|
|
return 1;
|
|
}
|
|
/* Not compressible */
|
|
if (maxSymbolValue > (241-128)) return ERROR(GENERIC); /* not implemented (not possible with current format) */
|
|
if (((maxSymbolValue+1)/2) + 1 > maxDstSize) return ERROR(dstSize_tooSmall); /* not enough space within dst buffer */
|
|
op[0] = (BYTE)(128 /*special case*/ + 0 /* Not Compressible */ + (maxSymbolValue-1));
|
|
huffWeight[maxSymbolValue] = 0; /* to be sure it doesn't cause issue in final combination */
|
|
for (n=0; n<maxSymbolValue; n+=2)
|
|
op[(n/2)+1] = (BYTE)((huffWeight[n] << 4) + huffWeight[n+1]);
|
|
return ((maxSymbolValue+1)/2) + 1;
|
|
}
|
|
|
|
/* normal header case */
|
|
op[0] = (BYTE)size;
|
|
return size+1;
|
|
}
|
|
|
|
|
|
|
|
size_t HUF_readCTable (HUF_CElt* CTable, U32 maxSymbolValue, const void* src, size_t srcSize)
|
|
{
|
|
BYTE huffWeight[HUF_MAX_SYMBOL_VALUE + 1];
|
|
U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1]; /* large enough for values from 0 to 16 */
|
|
U32 tableLog = 0;
|
|
size_t readSize;
|
|
U32 nbSymbols = 0;
|
|
//memset(huffWeight, 0, sizeof(huffWeight)); /* is not necessary, even though some analyzer complain ... */
|
|
|
|
/* get symbol weights */
|
|
readSize = HUF_readStats(huffWeight, HUF_MAX_SYMBOL_VALUE+1, rankVal, &nbSymbols, &tableLog, src, srcSize);
|
|
if (HUF_isError(readSize)) return readSize;
|
|
|
|
/* check result */
|
|
if (tableLog > HUF_MAX_TABLELOG) return ERROR(tableLog_tooLarge);
|
|
if (nbSymbols > maxSymbolValue+1) return ERROR(maxSymbolValue_tooSmall);
|
|
|
|
/* Prepare base value per rank */
|
|
{ U32 n, nextRankStart = 0;
|
|
for (n=1; n<=tableLog; n++) {
|
|
U32 current = nextRankStart;
|
|
nextRankStart += (rankVal[n] << (n-1));
|
|
rankVal[n] = current;
|
|
} }
|
|
|
|
/* fill nbBits */
|
|
{ U32 n; for (n=0; n<nbSymbols; n++) {
|
|
const U32 w = huffWeight[n];
|
|
CTable[n].nbBits = (BYTE)(tableLog + 1 - w);
|
|
}}
|
|
|
|
/* fill val */
|
|
{ U16 nbPerRank[HUF_MAX_TABLELOG+1] = {0};
|
|
U16 valPerRank[HUF_MAX_TABLELOG+1] = {0};
|
|
{ U32 n; for (n=0; n<nbSymbols; n++) nbPerRank[CTable[n].nbBits]++; }
|
|
/* determine stating value per rank */
|
|
{ U16 min = 0;
|
|
U32 n; for (n=HUF_MAX_TABLELOG; n>0; n--) {
|
|
valPerRank[n] = min; /* get starting value within each rank */
|
|
min += nbPerRank[n];
|
|
min >>= 1;
|
|
} }
|
|
/* assign value within rank, symbol order */
|
|
{ U32 n; for (n=0; n<=maxSymbolValue; n++) CTable[n].val = valPerRank[CTable[n].nbBits]++; }
|
|
}
|
|
|
|
return readSize;
|
|
}
|
|
|
|
|
|
static U32 HUF_setMaxHeight(nodeElt* huffNode, U32 lastNonNull, U32 maxNbBits)
|
|
{
|
|
const U32 largestBits = huffNode[lastNonNull].nbBits;
|
|
if (largestBits <= maxNbBits) return largestBits; /* early exit : no elt > maxNbBits */
|
|
|
|
/* there are several too large elements (at least >= 2) */
|
|
{ int totalCost = 0;
|
|
const U32 baseCost = 1 << (largestBits - maxNbBits);
|
|
U32 n = lastNonNull;
|
|
|
|
while (huffNode[n].nbBits > maxNbBits) {
|
|
totalCost += baseCost - (1 << (largestBits - huffNode[n].nbBits));
|
|
huffNode[n].nbBits = (BYTE)maxNbBits;
|
|
n --;
|
|
} /* n stops at huffNode[n].nbBits <= maxNbBits */
|
|
while (huffNode[n].nbBits == maxNbBits) n--; /* n end at index of smallest symbol using < maxNbBits */
|
|
|
|
/* renorm totalCost */
|
|
totalCost >>= (largestBits - maxNbBits); /* note : totalCost is necessarily a multiple of baseCost */
|
|
|
|
/* repay normalized cost */
|
|
{ U32 const noSymbol = 0xF0F0F0F0;
|
|
U32 rankLast[HUF_MAX_TABLELOG+1];
|
|
int pos;
|
|
|
|
/* Get pos of last (smallest) symbol per rank */
|
|
memset(rankLast, 0xF0, sizeof(rankLast));
|
|
{ U32 currentNbBits = maxNbBits;
|
|
for (pos=n ; pos >= 0; pos--) {
|
|
if (huffNode[pos].nbBits >= currentNbBits) continue;
|
|
currentNbBits = huffNode[pos].nbBits; /* < maxNbBits */
|
|
rankLast[maxNbBits-currentNbBits] = pos;
|
|
} }
|
|
|
|
while (totalCost > 0) {
|
|
U32 nBitsToDecrease = BIT_highbit32(totalCost) + 1;
|
|
for ( ; nBitsToDecrease > 1; nBitsToDecrease--) {
|
|
U32 highPos = rankLast[nBitsToDecrease];
|
|
U32 lowPos = rankLast[nBitsToDecrease-1];
|
|
if (highPos == noSymbol) continue;
|
|
if (lowPos == noSymbol) break;
|
|
{ U32 const highTotal = huffNode[highPos].count;
|
|
U32 const lowTotal = 2 * huffNode[lowPos].count;
|
|
if (highTotal <= lowTotal) break;
|
|
} }
|
|
/* only triggered when no more rank 1 symbol left => find closest one (note : there is necessarily at least one !) */
|
|
while ((nBitsToDecrease<=HUF_MAX_TABLELOG) && (rankLast[nBitsToDecrease] == noSymbol)) /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */
|
|
nBitsToDecrease ++;
|
|
totalCost -= 1 << (nBitsToDecrease-1);
|
|
if (rankLast[nBitsToDecrease-1] == noSymbol)
|
|
rankLast[nBitsToDecrease-1] = rankLast[nBitsToDecrease]; /* this rank is no longer empty */
|
|
huffNode[rankLast[nBitsToDecrease]].nbBits ++;
|
|
if (rankLast[nBitsToDecrease] == 0) /* special case, reached largest symbol */
|
|
rankLast[nBitsToDecrease] = noSymbol;
|
|
else {
|
|
rankLast[nBitsToDecrease]--;
|
|
if (huffNode[rankLast[nBitsToDecrease]].nbBits != maxNbBits-nBitsToDecrease)
|
|
rankLast[nBitsToDecrease] = noSymbol; /* this rank is now empty */
|
|
} } /* while (totalCost > 0) */
|
|
|
|
while (totalCost < 0) { /* Sometimes, cost correction overshoot */
|
|
if (rankLast[1] == noSymbol) { /* special case : no rank 1 symbol (using maxNbBits-1); let's create one from largest rank 0 (using maxNbBits) */
|
|
while (huffNode[n].nbBits == maxNbBits) n--;
|
|
huffNode[n+1].nbBits--;
|
|
rankLast[1] = n+1;
|
|
totalCost++;
|
|
continue;
|
|
}
|
|
huffNode[ rankLast[1] + 1 ].nbBits--;
|
|
rankLast[1]++;
|
|
totalCost ++;
|
|
} } } /* there are several too large elements (at least >= 2) */
|
|
|
|
return maxNbBits;
|
|
}
|
|
|
|
|
|
typedef struct {
|
|
U32 base;
|
|
U32 current;
|
|
} rankPos;
|
|
|
|
static void HUF_sort(nodeElt* huffNode, const U32* count, U32 maxSymbolValue)
|
|
{
|
|
rankPos rank[32];
|
|
U32 n;
|
|
|
|
memset(rank, 0, sizeof(rank));
|
|
for (n=0; n<=maxSymbolValue; n++) {
|
|
U32 r = BIT_highbit32(count[n] + 1);
|
|
rank[r].base ++;
|
|
}
|
|
for (n=30; n>0; n--) rank[n-1].base += rank[n].base;
|
|
for (n=0; n<32; n++) rank[n].current = rank[n].base;
|
|
for (n=0; n<=maxSymbolValue; n++) {
|
|
U32 const c = count[n];
|
|
U32 const r = BIT_highbit32(c+1) + 1;
|
|
U32 pos = rank[r].current++;
|
|
while ((pos > rank[r].base) && (c > huffNode[pos-1].count)) huffNode[pos]=huffNode[pos-1], pos--;
|
|
huffNode[pos].count = c;
|
|
huffNode[pos].byte = (BYTE)n;
|
|
}
|
|
}
|
|
|
|
|
|
#define STARTNODE (HUF_MAX_SYMBOL_VALUE+1)
|
|
size_t HUF_buildCTable (HUF_CElt* tree, const U32* count, U32 maxSymbolValue, U32 maxNbBits)
|
|
{
|
|
nodeElt huffNode0[2*HUF_MAX_SYMBOL_VALUE+1 +1];
|
|
nodeElt* huffNode = huffNode0 + 1;
|
|
U32 n, nonNullRank;
|
|
int lowS, lowN;
|
|
U16 nodeNb = STARTNODE;
|
|
U32 nodeRoot;
|
|
|
|
/* safety checks */
|
|
if (maxNbBits == 0) maxNbBits = HUF_DEFAULT_TABLELOG;
|
|
if (maxSymbolValue > HUF_MAX_SYMBOL_VALUE) return ERROR(GENERIC);
|
|
memset(huffNode0, 0, sizeof(huffNode0));
|
|
|
|
/* sort, decreasing order */
|
|
HUF_sort(huffNode, count, maxSymbolValue);
|
|
|
|
/* init for parents */
|
|
nonNullRank = maxSymbolValue;
|
|
while(huffNode[nonNullRank].count == 0) nonNullRank--;
|
|
lowS = nonNullRank; nodeRoot = nodeNb + lowS - 1; lowN = nodeNb;
|
|
huffNode[nodeNb].count = huffNode[lowS].count + huffNode[lowS-1].count;
|
|
huffNode[lowS].parent = huffNode[lowS-1].parent = nodeNb;
|
|
nodeNb++; lowS-=2;
|
|
for (n=nodeNb; n<=nodeRoot; n++) huffNode[n].count = (U32)(1U<<30);
|
|
huffNode0[0].count = (U32)(1U<<31);
|
|
|
|
/* create parents */
|
|
while (nodeNb <= nodeRoot) {
|
|
U32 n1 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++;
|
|
U32 n2 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++;
|
|
huffNode[nodeNb].count = huffNode[n1].count + huffNode[n2].count;
|
|
huffNode[n1].parent = huffNode[n2].parent = nodeNb;
|
|
nodeNb++;
|
|
}
|
|
|
|
/* distribute weights (unlimited tree height) */
|
|
huffNode[nodeRoot].nbBits = 0;
|
|
for (n=nodeRoot-1; n>=STARTNODE; n--)
|
|
huffNode[n].nbBits = huffNode[ huffNode[n].parent ].nbBits + 1;
|
|
for (n=0; n<=nonNullRank; n++)
|
|
huffNode[n].nbBits = huffNode[ huffNode[n].parent ].nbBits + 1;
|
|
|
|
/* enforce maxTableLog */
|
|
maxNbBits = HUF_setMaxHeight(huffNode, nonNullRank, maxNbBits);
|
|
|
|
/* fill result into tree (val, nbBits) */
|
|
{ U16 nbPerRank[HUF_MAX_TABLELOG+1] = {0};
|
|
U16 valPerRank[HUF_MAX_TABLELOG+1] = {0};
|
|
if (maxNbBits > HUF_MAX_TABLELOG) return ERROR(GENERIC); /* check fit into table */
|
|
for (n=0; n<=nonNullRank; n++)
|
|
nbPerRank[huffNode[n].nbBits]++;
|
|
/* determine stating value per rank */
|
|
{ U16 min = 0;
|
|
for (n=maxNbBits; n>0; n--) {
|
|
valPerRank[n] = min; /* get starting value within each rank */
|
|
min += nbPerRank[n];
|
|
min >>= 1;
|
|
} }
|
|
for (n=0; n<=maxSymbolValue; n++)
|
|
tree[huffNode[n].byte].nbBits = huffNode[n].nbBits; /* push nbBits per symbol, symbol order */
|
|
for (n=0; n<=maxSymbolValue; n++)
|
|
tree[n].val = valPerRank[tree[n].nbBits]++; /* assign value within rank, symbol order */
|
|
}
|
|
|
|
return maxNbBits;
|
|
}
|
|
|
|
static void HUF_encodeSymbol(BIT_CStream_t* bitCPtr, U32 symbol, const HUF_CElt* CTable)
|
|
{
|
|
BIT_addBitsFast(bitCPtr, CTable[symbol].val, CTable[symbol].nbBits);
|
|
}
|
|
|
|
size_t HUF_compressBound(size_t size) { return HUF_COMPRESSBOUND(size); }
|
|
|
|
#define HUF_FLUSHBITS(s) (fast ? BIT_flushBitsFast(s) : BIT_flushBits(s))
|
|
|
|
#define HUF_FLUSHBITS_1(stream) \
|
|
if (sizeof((stream)->bitContainer)*8 < HUF_MAX_TABLELOG*2+7) HUF_FLUSHBITS(stream)
|
|
|
|
#define HUF_FLUSHBITS_2(stream) \
|
|
if (sizeof((stream)->bitContainer)*8 < HUF_MAX_TABLELOG*4+7) HUF_FLUSHBITS(stream)
|
|
|
|
size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable)
|
|
{
|
|
const BYTE* ip = (const BYTE*) src;
|
|
BYTE* const ostart = (BYTE*)dst;
|
|
BYTE* const oend = ostart + dstSize;
|
|
BYTE* op = ostart;
|
|
size_t n;
|
|
const unsigned fast = (dstSize >= HUF_BLOCKBOUND(srcSize));
|
|
BIT_CStream_t bitC;
|
|
|
|
/* init */
|
|
if (dstSize < 8) return 0; /* not enough space to compress */
|
|
{ size_t const errorCode = BIT_initCStream(&bitC, op, oend-op);
|
|
if (HUF_isError(errorCode)) return 0; }
|
|
|
|
n = srcSize & ~3; /* join to mod 4 */
|
|
switch (srcSize & 3)
|
|
{
|
|
case 3 : HUF_encodeSymbol(&bitC, ip[n+ 2], CTable);
|
|
HUF_FLUSHBITS_2(&bitC);
|
|
case 2 : HUF_encodeSymbol(&bitC, ip[n+ 1], CTable);
|
|
HUF_FLUSHBITS_1(&bitC);
|
|
case 1 : HUF_encodeSymbol(&bitC, ip[n+ 0], CTable);
|
|
HUF_FLUSHBITS(&bitC);
|
|
case 0 :
|
|
default: ;
|
|
}
|
|
|
|
for (; n>0; n-=4) { /* note : n&3==0 at this stage */
|
|
HUF_encodeSymbol(&bitC, ip[n- 1], CTable);
|
|
HUF_FLUSHBITS_1(&bitC);
|
|
HUF_encodeSymbol(&bitC, ip[n- 2], CTable);
|
|
HUF_FLUSHBITS_2(&bitC);
|
|
HUF_encodeSymbol(&bitC, ip[n- 3], CTable);
|
|
HUF_FLUSHBITS_1(&bitC);
|
|
HUF_encodeSymbol(&bitC, ip[n- 4], CTable);
|
|
HUF_FLUSHBITS(&bitC);
|
|
}
|
|
|
|
return BIT_closeCStream(&bitC);
|
|
}
|
|
|
|
|
|
size_t HUF_compress4X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable)
|
|
{
|
|
size_t segmentSize = (srcSize+3)/4; /* first 3 segments */
|
|
const BYTE* ip = (const BYTE*) src;
|
|
const BYTE* const iend = ip + srcSize;
|
|
BYTE* const ostart = (BYTE*) dst;
|
|
BYTE* const oend = ostart + dstSize;
|
|
BYTE* op = ostart;
|
|
size_t errorCode;
|
|
|
|
if (dstSize < 6 + 1 + 1 + 1 + 8) return 0; /* minimum space to compress successfully */
|
|
if (srcSize < 12) return 0; /* no saving possible : too small input */
|
|
op += 6; /* jumpTable */
|
|
|
|
errorCode = HUF_compress1X_usingCTable(op, oend-op, ip, segmentSize, CTable);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
if (errorCode==0) return 0;
|
|
MEM_writeLE16(ostart, (U16)errorCode);
|
|
|
|
ip += segmentSize;
|
|
op += errorCode;
|
|
errorCode = HUF_compress1X_usingCTable(op, oend-op, ip, segmentSize, CTable);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
if (errorCode==0) return 0;
|
|
MEM_writeLE16(ostart+2, (U16)errorCode);
|
|
|
|
ip += segmentSize;
|
|
op += errorCode;
|
|
errorCode = HUF_compress1X_usingCTable(op, oend-op, ip, segmentSize, CTable);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
if (errorCode==0) return 0;
|
|
MEM_writeLE16(ostart+4, (U16)errorCode);
|
|
|
|
ip += segmentSize;
|
|
op += errorCode;
|
|
errorCode = HUF_compress1X_usingCTable(op, oend-op, ip, iend-ip, CTable);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
if (errorCode==0) return 0;
|
|
|
|
op += errorCode;
|
|
return op-ostart;
|
|
}
|
|
|
|
|
|
static size_t HUF_compress_internal (
|
|
void* dst, size_t dstSize,
|
|
const void* src, size_t srcSize,
|
|
unsigned maxSymbolValue, unsigned huffLog,
|
|
unsigned singleStream)
|
|
{
|
|
BYTE* const ostart = (BYTE*)dst;
|
|
BYTE* const oend = ostart + dstSize;
|
|
BYTE* op = ostart;
|
|
|
|
U32 count[HUF_MAX_SYMBOL_VALUE+1];
|
|
HUF_CElt CTable[HUF_MAX_SYMBOL_VALUE+1];
|
|
size_t errorCode;
|
|
|
|
/* checks & inits */
|
|
if (srcSize < 1) return 0; /* Uncompressed - note : 1 means rle, so first byte must be correct */
|
|
if (dstSize < 1) return 0; /* not compressible within dst budget */
|
|
if (srcSize > 128 * 1024) return ERROR(srcSize_wrong); /* current block size limit */
|
|
if (huffLog > HUF_MAX_TABLELOG) return ERROR(tableLog_tooLarge);
|
|
if (!maxSymbolValue) maxSymbolValue = HUF_MAX_SYMBOL_VALUE;
|
|
if (!huffLog) huffLog = HUF_DEFAULT_TABLELOG;
|
|
|
|
/* Scan input and build symbol stats */
|
|
errorCode = FSE_count (count, &maxSymbolValue, (const BYTE*)src, srcSize);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
if (errorCode == srcSize) { *ostart = ((const BYTE*)src)[0]; return 1; }
|
|
if (errorCode <= (srcSize >> 7)+1) return 0; /* Heuristic : not compressible enough */
|
|
|
|
/* Build Huffman Tree */
|
|
errorCode = HUF_buildCTable (CTable, count, maxSymbolValue, huffLog);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
huffLog = (U32)errorCode;
|
|
|
|
/* Write table description header */
|
|
errorCode = HUF_writeCTable (op, dstSize, CTable, maxSymbolValue, huffLog);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
if (errorCode + 12 >= srcSize) return 0; /* not useful to try compression */
|
|
op += errorCode;
|
|
|
|
/* Compress */
|
|
if (singleStream)
|
|
errorCode = HUF_compress1X_usingCTable(op, oend - op, src, srcSize, CTable); /* single segment */
|
|
else
|
|
errorCode = HUF_compress4X_usingCTable(op, oend - op, src, srcSize, CTable);
|
|
if (HUF_isError(errorCode)) return errorCode;
|
|
if (errorCode==0) return 0;
|
|
op += errorCode;
|
|
|
|
/* check compressibility */
|
|
if ((size_t)(op-ostart) >= srcSize-1)
|
|
return 0;
|
|
|
|
return op-ostart;
|
|
}
|
|
|
|
|
|
size_t HUF_compress1X (void* dst, size_t dstSize,
|
|
const void* src, size_t srcSize,
|
|
unsigned maxSymbolValue, unsigned huffLog)
|
|
{
|
|
return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 1);
|
|
}
|
|
|
|
size_t HUF_compress2 (void* dst, size_t dstSize,
|
|
const void* src, size_t srcSize,
|
|
unsigned maxSymbolValue, unsigned huffLog)
|
|
{
|
|
return HUF_compress_internal(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, 0);
|
|
}
|
|
|
|
|
|
size_t HUF_compress (void* dst, size_t maxDstSize, const void* src, size_t srcSize)
|
|
{
|
|
return HUF_compress2(dst, maxDstSize, src, (U32)srcSize, 255, HUF_DEFAULT_TABLELOG);
|
|
}
|