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/* LzFind.c -- Match finder for LZ algorithms↩
2017-06-10 : Igor Pavlov : Public domain */↩
↩
#include "Precomp.h"↩
↩
#include <string.h>↩
↩
#include "LzFind.h"↩
#include "LzHash.h"↩
↩
#define kEmptyHashValue 0↩
#define kMaxValForNormalize ((UInt32)0xFFFFFFFF)↩
#define kNormalizeStepMin (1 << 10) /* it must be power of 2 */↩
#define kNormalizeMask (~(UInt32)(kNormalizeStepMin - 1))↩
#define kMaxHistorySize ((UInt32)7 << 29)↩
↩
#define kStartMaxLen 3↩
↩
static void LzInWindow_Free(CMatchFinder *p, ISzAllocPtr alloc)↩
{↩
if (!p->directInput)↩
{↩
ISzAlloc_Free(alloc, p->bufferBase);↩
p->bufferBase = NULL;↩
}↩
}↩
↩
/* keepSizeBefore + keepSizeAfter + keepSizeReserv must be < 4G) */↩
↩
static int LzInWindow_Create(CMatchFinder *p, UInt32 keepSizeReserv, ISzAllocPtr alloc)↩
{↩
UInt32 blockSize = p->keepSizeBefore + p->keepSizeAfter + keepSizeReserv;↩
if (p->directInput)↩
{↩
p->blockSize = blockSize;↩
return 1;↩
}↩
if (!p->bufferBase || p->blockSize != blockSize)↩
{↩
LzInWindow_Free(p, alloc);↩
p->blockSize = blockSize;↩
p->bufferBase = (Byte *)ISzAlloc_Alloc(alloc, (size_t)blockSize);↩
}↩
return (p->bufferBase != NULL);↩
}↩
↩
Byte *MatchFinder_GetPointerToCurrentPos(CMatchFinder *p) { return p->buffer; }↩
↩
UInt32 MatchFinder_GetNumAvailableBytes(CMatchFinder *p) { return p->streamPos - p->pos; }↩
↩
void MatchFinder_ReduceOffsets(CMatchFinder *p, UInt32 subValue)↩
{↩
p->posLimit -= subValue;↩
p->pos -= subValue;↩
p->streamPos -= subValue;↩
}↩
↩
static void MatchFinder_ReadBlock(CMatchFinder *p)↩
{↩
if (p->streamEndWasReached || p->result != SZ_OK)↩
return;↩
↩
/* We use (p->streamPos - p->pos) value. (p->streamPos < p->pos) is allowed. */↩
↩
if (p->directInput)↩
{↩
UInt32 curSize = 0xFFFFFFFF - (p->streamPos - p->pos);↩
if (curSize > p->directInputRem)↩
curSize = (UInt32)p->directInputRem;↩
p->directInputRem -= curSize;↩
p->streamPos += curSize;↩
if (p->directInputRem == 0)↩
p->streamEndWasReached = 1;↩
return;↩
}↩
↩
for (;;)↩
{↩
Byte *dest = p->buffer + (p->streamPos - p->pos);↩
size_t size = (p->bufferBase + p->blockSize - dest);↩
if (size == 0)↩
return;↩
↩
p->result = ISeqInStream_Read(p->stream, dest, &size);↩
if (p->result != SZ_OK)↩
return;↩
if (size == 0)↩
{↩
p->streamEndWasReached = 1;↩
return;↩
}↩
p->streamPos += (UInt32)size;↩
if (p->streamPos - p->pos > p->keepSizeAfter)↩
return;↩
}↩
}↩
↩
void MatchFinder_MoveBlock(CMatchFinder *p)↩
{↩
memmove(p->bufferBase,↩
p->buffer - p->keepSizeBefore,↩
(size_t)(p->streamPos - p->pos) + p->keepSizeBefore);↩
p->buffer = p->bufferBase + p->keepSizeBefore;↩
}↩
↩
int MatchFinder_NeedMove(CMatchFinder *p)↩
{↩
if (p->directInput)↩
return 0;↩
/* if (p->streamEndWasReached) return 0; */↩
return ((size_t)(p->bufferBase + p->blockSize - p->buffer) <= p->keepSizeAfter);↩
}↩
↩
void MatchFinder_ReadIfRequired(CMatchFinder *p)↩
{↩
if (p->streamEndWasReached)↩
return;↩
if (p->keepSizeAfter >= p->streamPos - p->pos)↩
MatchFinder_ReadBlock(p);↩
}↩
↩
static void MatchFinder_CheckAndMoveAndRead(CMatchFinder *p)↩
{↩
if (MatchFinder_NeedMove(p))↩
MatchFinder_MoveBlock(p);↩
MatchFinder_ReadBlock(p);↩
}↩
↩
static void MatchFinder_SetDefaultSettings(CMatchFinder *p)↩
{↩
p->cutValue = 32;↩
p->btMode = 1;↩
p->numHashBytes = 4;↩
p->bigHash = 0;↩
}↩
↩
#define kCrcPoly 0xEDB88320↩
↩
void MatchFinder_Construct(CMatchFinder *p)↩
{↩
UInt32 i;↩
p->bufferBase = NULL;↩
p->directInput = 0;↩
p->hash = NULL;↩
p->expectedDataSize = (UInt64)(Int64)-1;↩
MatchFinder_SetDefaultSettings(p);↩
↩
for (i = 0; i < 256; i++)↩
{↩
UInt32 r = i;↩
unsigned j;↩
for (j = 0; j < 8; j++)↩
r = (r >> 1) ^ (kCrcPoly & ((UInt32)0 - (r & 1)));↩
p->crc[i] = r;↩
}↩
}↩
↩
static void MatchFinder_FreeThisClassMemory(CMatchFinder *p, ISzAllocPtr alloc)↩
{↩
ISzAlloc_Free(alloc, p->hash);↩
p->hash = NULL;↩
}↩
↩
void MatchFinder_Free(CMatchFinder *p, ISzAllocPtr alloc)↩
{↩
MatchFinder_FreeThisClassMemory(p, alloc);↩
LzInWindow_Free(p, alloc);↩
}↩
↩
static CLzRef* AllocRefs(size_t num, ISzAllocPtr alloc)↩
{↩
size_t sizeInBytes = (size_t)num * sizeof(CLzRef);↩
if (sizeInBytes / sizeof(CLzRef) != num)↩
return NULL;↩
return (CLzRef *)ISzAlloc_Alloc(alloc, sizeInBytes);↩
}↩
↩
int MatchFinder_Create(CMatchFinder *p, UInt32 historySize,↩
UInt32 keepAddBufferBefore, UInt32 matchMaxLen, UInt32 keepAddBufferAfter,↩
ISzAllocPtr alloc)↩
{↩
UInt32 sizeReserv;↩
↩
if (historySize > kMaxHistorySize)↩
{↩
MatchFinder_Free(p, alloc);↩
return 0;↩
}↩
↩
sizeReserv = historySize >> 1;↩
if (historySize >= ((UInt32)3 << 30)) sizeReserv = historySize >> 3;↩
else if (historySize >= ((UInt32)2 << 30)) sizeReserv = historySize >> 2;↩
↩
sizeReserv += (keepAddBufferBefore + matchMaxLen + keepAddBufferAfter) / 2 + (1 << 19);↩
↩
p->keepSizeBefore = historySize + keepAddBufferBefore + 1;↩
p->keepSizeAfter = matchMaxLen + keepAddBufferAfter;↩
↩
/* we need one additional byte, since we use MoveBlock after pos++ and before dictionary using */↩
↩
if (LzInWindow_Create(p, sizeReserv, alloc))↩
{↩
UInt32 newCyclicBufferSize = historySize + 1;↩
UInt32 hs;↩
p->matchMaxLen = matchMaxLen;↩
{↩
p->fixedHashSize = 0;↩
if (p->numHashBytes == 2)↩
hs = (1 << 16) - 1;↩
else↩
{↩
hs = historySize;↩
if (hs > p->expectedDataSize)↩
hs = (UInt32)p->expectedDataSize;↩
if (hs != 0)↩
hs--;↩
hs |= (hs >> 1);↩
hs |= (hs >> 2);↩
hs |= (hs >> 4);↩
hs |= (hs >> 8);↩
hs >>= 1;↩
hs |= 0xFFFF; /* don't change it! It's required for Deflate */↩
if (hs > (1 << 24))↩
{↩
if (p->numHashBytes == 3)↩
hs = (1 << 24) - 1;↩
else↩
hs >>= 1;↩
/* if (bigHash) mode, GetHeads4b() in LzFindMt.c needs (hs >= ((1 << 24) - 1))) */↩
}↩
}↩
p->hashMask = hs;↩
hs++;↩
if (p->numHashBytes > 2) p->fixedHashSize += kHash2Size;↩
if (p->numHashBytes > 3) p->fixedHashSize += kHash3Size;↩
if (p->numHashBytes > 4) p->fixedHashSize += kHash4Size;↩
hs += p->fixedHashSize;↩
}↩
↩
{↩
size_t newSize;↩
size_t numSons;↩
p->historySize = historySize;↩
p->hashSizeSum = hs;↩
p->cyclicBufferSize = newCyclicBufferSize;↩
↩
numSons = newCyclicBufferSize;↩
if (p->btMode)↩
numSons <<= 1;↩
newSize = hs + numSons;↩
↩
if (p->hash && p->numRefs == newSize)↩
return 1;↩
↩
MatchFinder_FreeThisClassMemory(p, alloc);↩
p->numRefs = newSize;↩
p->hash = AllocRefs(newSize, alloc);↩
↩
if (p->hash)↩
{↩
p->son = p->hash + p->hashSizeSum;↩
return 1;↩
}↩
}↩
}↩
↩
MatchFinder_Free(p, alloc);↩
return 0;↩
}↩
↩
static void MatchFinder_SetLimits(CMatchFinder *p)↩
{↩
UInt32 limit = kMaxValForNormalize - p->pos;↩
UInt32 limit2 = p->cyclicBufferSize - p->cyclicBufferPos;↩
↩
if (limit2 < limit)↩
limit = limit2;↩
limit2 = p->streamPos - p->pos;↩
↩
if (limit2 <= p->keepSizeAfter)↩
{↩
if (limit2 > 0)↩
limit2 = 1;↩
}↩
else↩
limit2 -= p->keepSizeAfter;↩
↩
if (limit2 < limit)↩
limit = limit2;↩
↩
{↩
UInt32 lenLimit = p->streamPos - p->pos;↩
if (lenLimit > p->matchMaxLen)↩
lenLimit = p->matchMaxLen;↩
p->lenLimit = lenLimit;↩
}↩
p->posLimit = p->pos + limit;↩
}↩
↩
↩
void MatchFinder_Init_LowHash(CMatchFinder *p)↩
{↩
size_t i;↩
CLzRef *items = p->hash;↩
size_t numItems = p->fixedHashSize;↩
for (i = 0; i < numItems; i++)↩
items[i] = kEmptyHashValue;↩
}↩
↩
↩
void MatchFinder_Init_HighHash(CMatchFinder *p)↩
{↩
size_t i;↩
CLzRef *items = p->hash + p->fixedHashSize;↩
size_t numItems = (size_t)p->hashMask + 1;↩
for (i = 0; i < numItems; i++)↩
items[i] = kEmptyHashValue;↩
}↩
↩
↩
void MatchFinder_Init_3(CMatchFinder *p, int readData)↩
{↩
p->cyclicBufferPos = 0;↩
p->buffer = p->bufferBase;↩
p->pos =↩
p->streamPos = p->cyclicBufferSize;↩
p->result = SZ_OK;↩
p->streamEndWasReached = 0;↩
↩
if (readData)↩
MatchFinder_ReadBlock(p);↩
↩
MatchFinder_SetLimits(p);↩
}↩
↩
↩
void MatchFinder_Init(CMatchFinder *p)↩
{↩
MatchFinder_Init_HighHash(p);↩
MatchFinder_Init_LowHash(p);↩
MatchFinder_Init_3(p, True);↩
}↩
↩
↩
static UInt32 MatchFinder_GetSubValue(CMatchFinder *p)↩
{↩
return (p->pos - p->historySize - 1) & kNormalizeMask;↩
}↩
↩
void MatchFinder_Normalize3(UInt32 subValue, CLzRef *items, size_t numItems)↩
{↩
size_t i;↩
for (i = 0; i < numItems; i++)↩
{↩
UInt32 value = items[i];↩
if (value <= subValue)↩
value = kEmptyHashValue;↩
else↩
value -= subValue;↩
items[i] = value;↩
}↩
}↩
↩
static void MatchFinder_Normalize(CMatchFinder *p)↩
{↩
UInt32 subValue = MatchFinder_GetSubValue(p);↩
MatchFinder_Normalize3(subValue, p->hash, p->numRefs);↩
MatchFinder_ReduceOffsets(p, subValue);↩
}↩
↩
static void MatchFinder_CheckLimits(CMatchFinder *p)↩
{↩
if (p->pos == kMaxValForNormalize)↩
MatchFinder_Normalize(p);↩
if (!p->streamEndWasReached && p->keepSizeAfter == p->streamPos - p->pos)↩
MatchFinder_CheckAndMoveAndRead(p);↩
if (p->cyclicBufferPos == p->cyclicBufferSize)↩
p->cyclicBufferPos = 0;↩
MatchFinder_SetLimits(p);↩
}↩
↩
static UInt32 * Hc_GetMatchesSpec(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *cur, CLzRef *son,↩
UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 cutValue,↩
UInt32 *distances, UInt32 maxLen)↩
{↩
son[_cyclicBufferPos] = curMatch;↩
for (;;)↩
{↩
UInt32 delta = pos - curMatch;↩
if (cutValue-- == 0 || delta >= _cyclicBufferSize)↩
return distances;↩
{↩
const Byte *pb = cur - delta;↩
curMatch = son[_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)];↩
if (pb[maxLen] == cur[maxLen] && *pb == *cur)↩
{↩
UInt32 len = 0;↩
while (++len != lenLimit)↩
if (pb[len] != cur[len])↩
break;↩
if (maxLen < len)↩
{↩
*distances++ = maxLen = len;↩
*distances++ = delta - 1;↩
if (len == lenLimit)↩
return distances;↩
}↩
}↩
}↩
}↩
}↩
↩
UInt32 * GetMatchesSpec1(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *cur, CLzRef *son,↩
UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 cutValue,↩
UInt32 *distances, UInt32 maxLen)↩
{↩
CLzRef *ptr0 = son + (_cyclicBufferPos << 1) + 1;↩
CLzRef *ptr1 = son + (_cyclicBufferPos << 1);↩
UInt32 len0 = 0, len1 = 0;↩
for (;;)↩
{↩
UInt32 delta = pos - curMatch;↩
if (cutValue-- == 0 || delta >= _cyclicBufferSize)↩
{↩
*ptr0 = *ptr1 = kEmptyHashValue;↩
return distances;↩
}↩
{↩
CLzRef *pair = son + ((_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)) << 1);↩
const Byte *pb = cur - delta;↩
UInt32 len = (len0 < len1 ? len0 : len1);↩
if (pb[len] == cur[len])↩
{↩
if (++len != lenLimit && pb[len] == cur[len])↩
while (++len != lenLimit)↩
if (pb[len] != cur[len])↩
break;↩
if (maxLen < len)↩
{↩
*distances++ = maxLen = len;↩
*distances++ = delta - 1;↩
if (len == lenLimit)↩
{↩
*ptr1 = pair[0];↩
*ptr0 = pair[1];↩
return distances;↩
}↩
}↩
}↩
if (pb[len] < cur[len])↩
{↩
*ptr1 = curMatch;↩
ptr1 = pair + 1;↩
curMatch = *ptr1;↩
len1 = len;↩
}↩
else↩
{↩
*ptr0 = curMatch;↩
ptr0 = pair;↩
curMatch = *ptr0;↩
len0 = len;↩
}↩
}↩
}↩
}↩
↩
static void SkipMatchesSpec(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *cur, CLzRef *son,↩
UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 cutValue)↩
{↩
CLzRef *ptr0 = son + (_cyclicBufferPos << 1) + 1;↩
CLzRef *ptr1 = son + (_cyclicBufferPos << 1);↩
UInt32 len0 = 0, len1 = 0;↩
for (;;)↩
{↩
UInt32 delta = pos - curMatch;↩
if (cutValue-- == 0 || delta >= _cyclicBufferSize)↩
{↩
*ptr0 = *ptr1 = kEmptyHashValue;↩
return;↩
}↩
{↩
CLzRef *pair = son + ((_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)) << 1);↩
const Byte *pb = cur - delta;↩
UInt32 len = (len0 < len1 ? len0 : len1);↩
if (pb[len] == cur[len])↩
{↩
while (++len != lenLimit)↩
if (pb[len] != cur[len])↩
break;↩
{↩
if (len == lenLimit)↩
{↩
*ptr1 = pair[0];↩
*ptr0 = pair[1];↩
return;↩
}↩
}↩
}↩
if (pb[len] < cur[len])↩
{↩
*ptr1 = curMatch;↩
ptr1 = pair + 1;↩
curMatch = *ptr1;↩
len1 = len;↩
}↩
else↩
{↩
*ptr0 = curMatch;↩
ptr0 = pair;↩
curMatch = *ptr0;↩
len0 = len;↩
}↩
}↩
}↩
}↩
↩
#define MOVE_POS \↩
++p->cyclicBufferPos; \↩
p->buffer++; \↩
if (++p->pos == p->posLimit) MatchFinder_CheckLimits(p);↩
↩
#define MOVE_POS_RET MOVE_POS return offset;↩
↩
static void MatchFinder_MovePos(CMatchFinder *p) { MOVE_POS; }↩
↩
#define GET_MATCHES_HEADER2(minLen, ret_op) \↩
UInt32 lenLimit; UInt32 hv; const Byte *cur; UInt32 curMatch; \↩
lenLimit = p->lenLimit; { if (lenLimit < minLen) { MatchFinder_MovePos(p); ret_op; }} \↩
cur = p->buffer;↩
↩
#define GET_MATCHES_HEADER(minLen) GET_MATCHES_HEADER2(minLen, return 0)↩
#define SKIP_HEADER(minLen) GET_MATCHES_HEADER2(minLen, continue)↩
↩
#define MF_PARAMS(p) p->pos, p->buffer, p->son, p->cyclicBufferPos, p->cyclicBufferSize, p->cutValue↩
↩
#define GET_MATCHES_FOOTER(offset, maxLen) \↩
offset = (UInt32)(GetMatchesSpec1(lenLimit, curMatch, MF_PARAMS(p), \↩
distances + offset, maxLen) - distances); MOVE_POS_RET;↩
↩
#define SKIP_FOOTER \↩
SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p)); MOVE_POS;↩
↩
#define UPDATE_maxLen { \↩
ptrdiff_t diff = (ptrdiff_t)0 - d2; \↩
const Byte *c = cur + maxLen; \↩
const Byte *lim = cur + lenLimit; \↩
for (; c != lim; c++) if (*(c + diff) != *c) break; \↩
maxLen = (UInt32)(c - cur); }↩
↩
static UInt32 Bt2_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 offset;↩
GET_MATCHES_HEADER(2)↩
HASH2_CALC;↩
curMatch = p->hash[hv];↩
p->hash[hv] = p->pos;↩
offset = 0;↩
GET_MATCHES_FOOTER(offset, 1)↩
}↩
↩
UInt32 Bt3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 offset;↩
GET_MATCHES_HEADER(3)↩
HASH_ZIP_CALC;↩
curMatch = p->hash[hv];↩
p->hash[hv] = p->pos;↩
offset = 0;↩
GET_MATCHES_FOOTER(offset, 2)↩
}↩
↩
static UInt32 Bt3_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 h2, d2, maxLen, offset, pos;↩
UInt32 *hash;↩
GET_MATCHES_HEADER(3)↩
↩
HASH3_CALC;↩
↩
hash = p->hash;↩
pos = p->pos;↩
↩
d2 = pos - hash[h2];↩
↩
curMatch = (hash + kFix3HashSize)[hv];↩
↩
hash[h2] = pos;↩
(hash + kFix3HashSize)[hv] = pos;↩
↩
maxLen = 2;↩
offset = 0;↩
↩
if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)↩
{↩
UPDATE_maxLen↩
distances[0] = maxLen;↩
distances[1] = d2 - 1;↩
offset = 2;↩
if (maxLen == lenLimit)↩
{↩
SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p));↩
MOVE_POS_RET;↩
}↩
}↩
↩
GET_MATCHES_FOOTER(offset, maxLen)↩
}↩
↩
static UInt32 Bt4_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 h2, h3, d2, d3, maxLen, offset, pos;↩
UInt32 *hash;↩
GET_MATCHES_HEADER(4)↩
↩
HASH4_CALC;↩
↩
hash = p->hash;↩
pos = p->pos;↩
↩
d2 = pos - hash[ h2];↩
d3 = pos - (hash + kFix3HashSize)[h3];↩
↩
curMatch = (hash + kFix4HashSize)[hv];↩
↩
hash[ h2] = pos;↩
(hash + kFix3HashSize)[h3] = pos;↩
(hash + kFix4HashSize)[hv] = pos;↩
↩
maxLen = 0;↩
offset = 0;↩
↩
if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)↩
{↩
distances[0] = maxLen = 2;↩
distances[1] = d2 - 1;↩
offset = 2;↩
}↩
↩
if (d2 != d3 && d3 < p->cyclicBufferSize && *(cur - d3) == *cur)↩
{↩
maxLen = 3;↩
distances[(size_t)offset + 1] = d3 - 1;↩
offset += 2;↩
d2 = d3;↩
}↩
↩
if (offset != 0)↩
{↩
UPDATE_maxLen↩
distances[(size_t)offset - 2] = maxLen;↩
if (maxLen == lenLimit)↩
{↩
SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p));↩
MOVE_POS_RET;↩
}↩
}↩
↩
if (maxLen < 3)↩
maxLen = 3;↩
↩
GET_MATCHES_FOOTER(offset, maxLen)↩
}↩
↩
/*↩
static UInt32 Bt5_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 h2, h3, h4, d2, d3, d4, maxLen, offset, pos;↩
UInt32 *hash;↩
GET_MATCHES_HEADER(5)↩
↩
HASH5_CALC;↩
↩
hash = p->hash;↩
pos = p->pos;↩
↩
d2 = pos - hash[ h2];↩
d3 = pos - (hash + kFix3HashSize)[h3];↩
d4 = pos - (hash + kFix4HashSize)[h4];↩
↩
curMatch = (hash + kFix5HashSize)[hv];↩
↩
hash[ h2] = pos;↩
(hash + kFix3HashSize)[h3] = pos;↩
(hash + kFix4HashSize)[h4] = pos;↩
(hash + kFix5HashSize)[hv] = pos;↩
↩
maxLen = 0;↩
offset = 0;↩
↩
if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)↩
{↩
distances[0] = maxLen = 2;↩
distances[1] = d2 - 1;↩
offset = 2;↩
if (*(cur - d2 + 2) == cur[2])↩
distances[0] = maxLen = 3;↩
else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)↩
{↩
distances[2] = maxLen = 3;↩
distances[3] = d3 - 1;↩
offset = 4;↩
d2 = d3;↩
}↩
}↩
else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)↩
{↩
distances[0] = maxLen = 3;↩
distances[1] = d3 - 1;↩
offset = 2;↩
d2 = d3;↩
}↩
↩
if (d2 != d4 && d4 < p->cyclicBufferSize↩
&& *(cur - d4) == *cur↩
&& *(cur - d4 + 3) == *(cur + 3))↩
{↩
maxLen = 4;↩
distances[(size_t)offset + 1] = d4 - 1;↩
offset += 2;↩
d2 = d4;↩
}↩
↩
if (offset != 0)↩
{↩
UPDATE_maxLen↩
distances[(size_t)offset - 2] = maxLen;↩
if (maxLen == lenLimit)↩
{↩
SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p));↩
MOVE_POS_RET;↩
}↩
}↩
↩
if (maxLen < 4)↩
maxLen = 4;↩
↩
GET_MATCHES_FOOTER(offset, maxLen)↩
}↩
*/↩
↩
static UInt32 Hc4_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 h2, h3, d2, d3, maxLen, offset, pos;↩
UInt32 *hash;↩
GET_MATCHES_HEADER(4)↩
↩
HASH4_CALC;↩
↩
hash = p->hash;↩
pos = p->pos;↩
↩
d2 = pos - hash[ h2];↩
d3 = pos - (hash + kFix3HashSize)[h3];↩
↩
curMatch = (hash + kFix4HashSize)[hv];↩
↩
hash[ h2] = pos;↩
(hash + kFix3HashSize)[h3] = pos;↩
(hash + kFix4HashSize)[hv] = pos;↩
↩
maxLen = 0;↩
offset = 0;↩
↩
if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)↩
{↩
distances[0] = maxLen = 2;↩
distances[1] = d2 - 1;↩
offset = 2;↩
}↩
↩
if (d2 != d3 && d3 < p->cyclicBufferSize && *(cur - d3) == *cur)↩
{↩
maxLen = 3;↩
distances[(size_t)offset + 1] = d3 - 1;↩
offset += 2;↩
d2 = d3;↩
}↩
↩
if (offset != 0)↩
{↩
UPDATE_maxLen↩
distances[(size_t)offset - 2] = maxLen;↩
if (maxLen == lenLimit)↩
{↩
p->son[p->cyclicBufferPos] = curMatch;↩
MOVE_POS_RET;↩
}↩
}↩
↩
if (maxLen < 3)↩
maxLen = 3;↩
↩
offset = (UInt32)(Hc_GetMatchesSpec(lenLimit, curMatch, MF_PARAMS(p),↩
distances + offset, maxLen) - (distances));↩
MOVE_POS_RET↩
}↩
↩
/*↩
static UInt32 Hc5_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 h2, h3, h4, d2, d3, d4, maxLen, offset, pos↩
UInt32 *hash;↩
GET_MATCHES_HEADER(5)↩
↩
HASH5_CALC;↩
↩
hash = p->hash;↩
pos = p->pos;↩
↩
d2 = pos - hash[ h2];↩
d3 = pos - (hash + kFix3HashSize)[h3];↩
d4 = pos - (hash + kFix4HashSize)[h4];↩
↩
curMatch = (hash + kFix5HashSize)[hv];↩
↩
hash[ h2] = pos;↩
(hash + kFix3HashSize)[h3] = pos;↩
(hash + kFix4HashSize)[h4] = pos;↩
(hash + kFix5HashSize)[hv] = pos;↩
↩
maxLen = 0;↩
offset = 0;↩
↩
if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)↩
{↩
distances[0] = maxLen = 2;↩
distances[1] = d2 - 1;↩
offset = 2;↩
if (*(cur - d2 + 2) == cur[2])↩
distances[0] = maxLen = 3;↩
else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)↩
{↩
distances[2] = maxLen = 3;↩
distances[3] = d3 - 1;↩
offset = 4;↩
d2 = d3;↩
}↩
}↩
else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)↩
{↩
distances[0] = maxLen = 3;↩
distances[1] = d3 - 1;↩
offset = 2;↩
d2 = d3;↩
}↩
↩
if (d2 != d4 && d4 < p->cyclicBufferSize↩
&& *(cur - d4) == *cur↩
&& *(cur - d4 + 3) == *(cur + 3))↩
{↩
maxLen = 4;↩
distances[(size_t)offset + 1] = d4 - 1;↩
offset += 2;↩
d2 = d4;↩
}↩
↩
if (offset != 0)↩
{↩
UPDATE_maxLen↩
distances[(size_t)offset - 2] = maxLen;↩
if (maxLen == lenLimit)↩
{↩
p->son[p->cyclicBufferPos] = curMatch;↩
MOVE_POS_RET;↩
}↩
}↩
↩
if (maxLen < 4)↩
maxLen = 4;↩
↩
offset = (UInt32)(Hc_GetMatchesSpec(lenLimit, curMatch, MF_PARAMS(p),↩
distances + offset, maxLen) - (distances));↩
MOVE_POS_RET↩
}↩
*/↩
↩
UInt32 Hc3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)↩
{↩
UInt32 offset;↩
GET_MATCHES_HEADER(3)↩
HASH_ZIP_CALC;↩
curMatch = p->hash[hv];↩
p->hash[hv] = p->pos;↩
offset = (UInt32)(Hc_GetMatchesSpec(lenLimit, curMatch, MF_PARAMS(p),↩
distances, 2) - (distances));↩
MOVE_POS_RET↩
}↩
↩
static void Bt2_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
SKIP_HEADER(2)↩
HASH2_CALC;↩
curMatch = p->hash[hv];↩
p->hash[hv] = p->pos;↩
SKIP_FOOTER↩
}↩
while (--num != 0);↩
}↩
↩
void Bt3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
SKIP_HEADER(3)↩
HASH_ZIP_CALC;↩
curMatch = p->hash[hv];↩
p->hash[hv] = p->pos;↩
SKIP_FOOTER↩
}↩
while (--num != 0);↩
}↩
↩
static void Bt3_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
UInt32 h2;↩
UInt32 *hash;↩
SKIP_HEADER(3)↩
HASH3_CALC;↩
hash = p->hash;↩
curMatch = (hash + kFix3HashSize)[hv];↩
hash[h2] =↩
(hash + kFix3HashSize)[hv] = p->pos;↩
SKIP_FOOTER↩
}↩
while (--num != 0);↩
}↩
↩
static void Bt4_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
UInt32 h2, h3;↩
UInt32 *hash;↩
SKIP_HEADER(4)↩
HASH4_CALC;↩
hash = p->hash;↩
curMatch = (hash + kFix4HashSize)[hv];↩
hash[ h2] =↩
(hash + kFix3HashSize)[h3] =↩
(hash + kFix4HashSize)[hv] = p->pos;↩
SKIP_FOOTER↩
}↩
while (--num != 0);↩
}↩
↩
/*↩
static void Bt5_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
UInt32 h2, h3, h4;↩
UInt32 *hash;↩
SKIP_HEADER(5)↩
HASH5_CALC;↩
hash = p->hash;↩
curMatch = (hash + kFix5HashSize)[hv];↩
hash[ h2] =↩
(hash + kFix3HashSize)[h3] =↩
(hash + kFix4HashSize)[h4] =↩
(hash + kFix5HashSize)[hv] = p->pos;↩
SKIP_FOOTER↩
}↩
while (--num != 0);↩
}↩
*/↩
↩
static void Hc4_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
UInt32 h2, h3;↩
UInt32 *hash;↩
SKIP_HEADER(4)↩
HASH4_CALC;↩
hash = p->hash;↩
curMatch = (hash + kFix4HashSize)[hv];↩
hash[ h2] =↩
(hash + kFix3HashSize)[h3] =↩
(hash + kFix4HashSize)[hv] = p->pos;↩
p->son[p->cyclicBufferPos] = curMatch;↩
MOVE_POS↩
}↩
while (--num != 0);↩
}↩
↩
/*↩
static void Hc5_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
UInt32 h2, h3, h4;↩
UInt32 *hash;↩
SKIP_HEADER(5)↩
HASH5_CALC;↩
hash = p->hash;↩
curMatch = hash + kFix5HashSize)[hv];↩
hash[ h2] =↩
(hash + kFix3HashSize)[h3] =↩
(hash + kFix4HashSize)[h4] =↩
(hash + kFix5HashSize)[hv] = p->pos;↩
p->son[p->cyclicBufferPos] = curMatch;↩
MOVE_POS↩
}↩
while (--num != 0);↩
}↩
*/↩
↩
void Hc3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num)↩
{↩
do↩
{↩
SKIP_HEADER(3)↩
HASH_ZIP_CALC;↩
curMatch = p->hash[hv];↩
p->hash[hv] = p->pos;↩
p->son[p->cyclicBufferPos] = curMatch;↩
MOVE_POS↩
}↩
while (--num != 0);↩
}↩
↩
void MatchFinder_CreateVTable(CMatchFinder *p, IMatchFinder *vTable)↩
{↩
vTable->Init = (Mf_Init_Func)MatchFinder_Init;↩
vTable->GetNumAvailableBytes = (Mf_GetNumAvailableBytes_Func)MatchFinder_GetNumAvailableBytes;↩
vTable->GetPointerToCurrentPos = (Mf_GetPointerToCurrentPos_Func)MatchFinder_GetPointerToCurrentPos;↩
if (!p->btMode)↩
{↩
/* if (p->numHashBytes <= 4) */↩
{↩
vTable->GetMatches = (Mf_GetMatches_Func)Hc4_MatchFinder_GetMatches;↩
vTable->Skip = (Mf_Skip_Func)Hc4_MatchFinder_Skip;↩
}↩
/*↩
else↩
{↩
vTable->GetMatches = (Mf_GetMatches_Func)Hc5_MatchFinder_GetMatches;↩
vTable->Skip = (Mf_Skip_Func)Hc5_MatchFinder_Skip;↩
}↩
*/↩
}↩
else if (p->numHashBytes == 2)↩
{↩
vTable->GetMatches = (Mf_GetMatches_Func)Bt2_MatchFinder_GetMatches;↩
vTable->Skip = (Mf_Skip_Func)Bt2_MatchFinder_Skip;↩
}↩
else if (p->numHashBytes == 3)↩
{↩
vTable->GetMatches = (Mf_GetMatches_Func)Bt3_MatchFinder_GetMatches;↩
vTable->Skip = (Mf_Skip_Func)Bt3_MatchFinder_Skip;↩
}↩
else /* if (p->numHashBytes == 4) */↩
{↩
vTable->GetMatches = (Mf_GetMatches_Func)Bt4_MatchFinder_GetMatches;↩
vTable->Skip = (Mf_Skip_Func)Bt4_MatchFinder_Skip;↩
}↩
/*↩
else↩
{↩
vTable->GetMatches = (Mf_GetMatches_Func)Bt5_MatchFinder_GetMatches;↩
vTable->Skip = (Mf_Skip_Func)Bt5_MatchFinder_Skip;↩
}↩
*/↩
}↩