/* LzFind.c -- Match finder for LZ algorithms | |
2015-10-15 : 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, ISzAlloc *alloc) | |
{ | |
if (!p->directInput) | |
{ | |
alloc->Free(alloc, p->bufferBase); | |
p->bufferBase = NULL; | |
} | |
} | |
/* keepSizeBefore + keepSizeAfter + keepSizeReserv must be < 4G) */ | |
static int LzInWindow_Create(CMatchFinder *p, UInt32 keepSizeReserv, ISzAlloc *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 *)alloc->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 = p->stream->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; | |
MatchFinder_SetDefaultSettings(p); | |
for (i = 0; i < 256; i++) | |
{ | |
UInt32 r = i; | |
unsigned j; | |
for (j = 0; j < 8; j++) | |
r = (r >> 1) ^ (kCrcPoly & ~((r & 1) - 1)); | |
p->crc[i] = r; | |
} | |
} | |
static void MatchFinder_FreeThisClassMemory(CMatchFinder *p, ISzAlloc *alloc) | |
{ | |
alloc->Free(alloc, p->hash); | |
p->hash = NULL; | |
} | |
void MatchFinder_Free(CMatchFinder *p, ISzAlloc *alloc) | |
{ | |
MatchFinder_FreeThisClassMemory(p, alloc); | |
LzInWindow_Free(p, alloc); | |
} | |
static CLzRef* AllocRefs(size_t num, ISzAlloc *alloc) | |
{ | |
size_t sizeInBytes = (size_t)num * sizeof(CLzRef); | |
if (sizeInBytes / sizeof(CLzRef) != num) | |
return NULL; | |
return (CLzRef *)alloc->Alloc(alloc, sizeInBytes); | |
} | |
int MatchFinder_Create(CMatchFinder *p, UInt32 historySize, | |
UInt32 keepAddBufferBefore, UInt32 matchMaxLen, UInt32 keepAddBufferAfter, | |
ISzAlloc *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 - 1; | |
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_2(CMatchFinder *p, int readData) | |
{ | |
UInt32 i; | |
UInt32 *hash = p->hash; | |
UInt32 num = p->hashSizeSum; | |
for (i = 0; i < num; i++) | |
hash[i] = kEmptyHashValue; | |
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_2(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[offset + 1] = d3 - 1; | |
offset += 2; | |
d2 = d3; | |
} | |
if (offset != 0) | |
{ | |
UPDATE_maxLen | |
distances[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[offset + 1] = d4 - 1; | |
offset += 2; | |
d2 = d4; | |
} | |
if (offset != 0) | |
{ | |
UPDATE_maxLen | |
distances[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[offset + 1] = d3 - 1; | |
offset += 2; | |
d2 = d3; | |
} | |
if (offset != 0) | |
{ | |
UPDATE_maxLen | |
distances[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[offset + 1] = d4 - 1; | |
offset += 2; | |
d2 = d4; | |
} | |
if (offset != 0) | |
{ | |
UPDATE_maxLen | |
distances[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 = p->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; | |
} | |
*/ | |
} |