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physfs/lzma/C/Compress/Lz/MatchFinder.c

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/* MatchFinder.c */
/* Please call InitCrcTable before */
#include <string.h>
#include "MatchFinder.h"
#include "LzHash.h"
#include "../../7zCrc.h"
#define kEmptyHashValue 0
#define kMaxValForNormalize ((UInt32)0xFFFFFFFF)
#define kNormalizeStepMin (1 << 10) /* it must be power of 2 */
#define kNormalizeMask (~(kNormalizeStepMin - 1))
#define kMaxHistorySize ((UInt32)3 << 30)
#define kStartMaxLen 3
void LzInWindow_Free(CMatchFinder *p, ISzAlloc *alloc)
{
if (!p->directInput)
{
alloc->Free(p->bufferBase);
p->bufferBase = 0;
}
}
/* keepSizeBefore + keepSizeAfter + keepSizeReserv must be < 4G) */
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 == 0 || p->blockSize != blockSize)
{
LzInWindow_Free(p, alloc);
p->blockSize = blockSize;
p->bufferBase = (Byte *)alloc->Alloc(blockSize);
}
return (p->bufferBase != 0);
}
Byte *MatchFinder_GetPointerToCurrentPos(CMatchFinder *p) { return p->buffer; }
Byte MatchFinder_GetIndexByte(CMatchFinder *p, Int32 index) { return p->buffer[index]; }
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;
}
void MatchFinder_ReadBlock(CMatchFinder *p)
{
if (p->streamEndWasReached || p->result != SZ_OK)
return;
for (;;)
{
Byte *dest = p->buffer + (p->streamPos - p->pos);
UInt32 numReadBytes;
UInt32 size = (UInt32)(p->bufferBase + p->blockSize - dest);
if (size == 0)
return;
p->result = p->stream->Read(p->stream, dest, size, &numReadBytes);
if (p->result != SZ_OK)
return;
if (numReadBytes == 0)
{
p->streamEndWasReached = 1;
return;
}
p->streamPos += numReadBytes;
if (p->streamPos - p->pos > p->keepSizeAfter)
return;
}
}
void MatchFinder_MoveBlock(CMatchFinder *p)
{
memmove(p->bufferBase,
p->buffer - p->keepSizeBefore,
p->streamPos - p->pos + p->keepSizeBefore);
p->buffer = p->bufferBase + p->keepSizeBefore;
}
int MatchFinder_NeedMove(CMatchFinder *p)
{
/* 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);
}
void MatchFinder_CheckAndMoveAndRead(CMatchFinder *p)
{
if (MatchFinder_NeedMove(p))
MatchFinder_MoveBlock(p);
MatchFinder_ReadBlock(p);
}
void MatchFinder_SetDefaultSettings(CMatchFinder *p)
{
p->cutValue = 32;
p->btMode = 1;
p->numHashBytes = 4;
/* p->skipModeBits = 0; */
p->directInput = 0;
p->bigHash = 0;
}
void MatchFinder_Construct(CMatchFinder *p)
{
p->bufferBase = 0;
p->directInput = 0;
p->hash = 0;
MatchFinder_SetDefaultSettings(p);
}
void MatchFinder_FreeThisClassMemory(CMatchFinder *p, ISzAlloc *alloc)
{
alloc->Free(p->hash);
p->hash = 0;
}
void MatchFinder_Free(CMatchFinder *p, ISzAlloc *alloc)
{
MatchFinder_FreeThisClassMemory(p, alloc);
LzInWindow_Free(p, alloc);
}
CLzRef* AllocRefs(UInt32 num, ISzAlloc *alloc)
{
size_t sizeInBytes = (size_t)num * sizeof(CLzRef);
if (sizeInBytes / sizeof(CLzRef) != num)
return 0;
return (CLzRef *)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)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 /* >> p->skipModeBits */) + 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 >>= p->skipModeBits; */
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;
}
}
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;
}
{
UInt32 prevSize = p->hashSizeSum + p->numSons;
UInt32 newSize;
p->historySize = historySize;
p->hashSizeSum = hs;
p->cyclicBufferSize = newCyclicBufferSize;
p->numSons = (p->btMode ? newCyclicBufferSize * 2 : newCyclicBufferSize);
newSize = p->hashSizeSum + p->numSons;
if (p->hash != 0 && prevSize == newSize)
return 1;
MatchFinder_FreeThisClassMemory(p, alloc);
p->hash = AllocRefs(newSize, alloc);
if (p->hash != 0)
{
p->son = p->hash + p->hashSizeSum;
return 1;
}
}
}
MatchFinder_Free(p, alloc);
return 0;
}
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(CMatchFinder *p)
{
UInt32 i;
for(i = 0; i < p->hashSizeSum; i++)
p->hash[i] = kEmptyHashValue;
p->cyclicBufferPos = 0;
p->buffer = p->bufferBase;
p->pos = p->streamPos = p->cyclicBufferSize;
p->result = SZ_OK;
p->streamEndWasReached = 0;
MatchFinder_ReadBlock(p);
MatchFinder_SetLimits(p);
}
UInt32 MatchFinder_GetSubValue(CMatchFinder *p)
{
return (p->pos - p->historySize - 1) & kNormalizeMask;
}
void MatchFinder_Normalize3(UInt32 subValue, CLzRef *items, UInt32 numItems)
{
UInt32 i;
for (i = 0; i < numItems; i++)
{
UInt32 value = items[i];
if (value <= subValue)
value = kEmptyHashValue;
else
value -= subValue;
items[i] = value;
}
}
void MatchFinder_Normalize(CMatchFinder *p)
{
UInt32 subValue = MatchFinder_GetSubValue(p);
MatchFinder_Normalize3(subValue, p->hash, p->hashSizeSum + p->numSons);
MatchFinder_ReduceOffsets(p, subValue);
}
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);
}
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;
}
}
}
}
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;
void MatchFinder_MovePos(CMatchFinder *p) { MOVE_POS; }
#define GET_MATCHES_HEADER2(minLen, ret_op) \
UInt32 lenLimit; UInt32 hashValue; 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;
UInt32 Bt2_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)
{
UInt32 offset;
GET_MATCHES_HEADER(2)
HASH2_CALC;
curMatch = p->hash[hashValue];
p->hash[hashValue] = 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[hashValue];
p->hash[hashValue] = p->pos;
offset = 0;
GET_MATCHES_FOOTER(offset, 2)
}
UInt32 Bt3_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)
{
UInt32 hash2Value, delta2, maxLen, offset;
GET_MATCHES_HEADER(3)
HASH3_CALC;
delta2 = p->pos - p->hash[hash2Value];
curMatch = p->hash[kFix3HashSize + hashValue];
p->hash[hash2Value] =
p->hash[kFix3HashSize + hashValue] = p->pos;
maxLen = 2;
offset = 0;
if (delta2 < p->cyclicBufferSize && *(cur - delta2) == *cur)
{
for (; maxLen != lenLimit; maxLen++)
if (cur[(ptrdiff_t)maxLen - delta2] != cur[maxLen])
break;
distances[0] = maxLen;
distances[1] = delta2 - 1;
offset = 2;
if (maxLen == lenLimit)
{
SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p));
MOVE_POS_RET;
}
}
GET_MATCHES_FOOTER(offset, maxLen)
}
UInt32 Bt4_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)
{
UInt32 hash2Value, hash3Value, delta2, delta3, maxLen, offset;
GET_MATCHES_HEADER(4)
HASH4_CALC;
delta2 = p->pos - p->hash[ hash2Value];
delta3 = p->pos - p->hash[kFix3HashSize + hash3Value];
curMatch = p->hash[kFix4HashSize + hashValue];
p->hash[ hash2Value] =
p->hash[kFix3HashSize + hash3Value] =
p->hash[kFix4HashSize + hashValue] = p->pos;
maxLen = 1;
offset = 0;
if (delta2 < p->cyclicBufferSize && *(cur - delta2) == *cur)
{
distances[0] = maxLen = 2;
distances[1] = delta2 - 1;
offset = 2;
}
if (delta2 != delta3 && delta3 < p->cyclicBufferSize && *(cur - delta3) == *cur)
{
maxLen = 3;
distances[offset + 1] = delta3 - 1;
offset += 2;
delta2 = delta3;
}
if (offset != 0)
{
for (; maxLen != lenLimit; maxLen++)
if (cur[(ptrdiff_t)maxLen - delta2] != cur[maxLen])
break;
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)
}
UInt32 Hc4_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)
{
UInt32 hash2Value, hash3Value, delta2, delta3, maxLen, offset;
GET_MATCHES_HEADER(4)
HASH4_CALC;
delta2 = p->pos - p->hash[ hash2Value];
delta3 = p->pos - p->hash[kFix3HashSize + hash3Value];
curMatch = p->hash[kFix4HashSize + hashValue];
p->hash[ hash2Value] =
p->hash[kFix3HashSize + hash3Value] =
p->hash[kFix4HashSize + hashValue] = p->pos;
maxLen = 1;
offset = 0;
if (delta2 < p->cyclicBufferSize && *(cur - delta2) == *cur)
{
distances[0] = maxLen = 2;
distances[1] = delta2 - 1;
offset = 2;
}
if (delta2 != delta3 && delta3 < p->cyclicBufferSize && *(cur - delta3) == *cur)
{
maxLen = 3;
distances[offset + 1] = delta3 - 1;
offset += 2;
delta2 = delta3;
}
if (offset != 0)
{
for (; maxLen != lenLimit; maxLen++)
if (cur[(ptrdiff_t)maxLen - delta2] != cur[maxLen])
break;
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
}
UInt32 Hc3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)
{
UInt32 offset;
GET_MATCHES_HEADER(3)
HASH_ZIP_CALC;
curMatch = p->hash[hashValue];
p->hash[hashValue] = p->pos;
offset = (UInt32)(Hc_GetMatchesSpec(lenLimit, curMatch, MF_PARAMS(p),
distances, 2) - (distances));
MOVE_POS_RET
}
void Bt2_MatchFinder_Skip(CMatchFinder *p, UInt32 num)
{
do
{
SKIP_HEADER(2)
HASH2_CALC;
curMatch = p->hash[hashValue];
p->hash[hashValue] = 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[hashValue];
p->hash[hashValue] = p->pos;
SKIP_FOOTER
}
while (--num != 0);
}
void Bt3_MatchFinder_Skip(CMatchFinder *p, UInt32 num)
{
do
{
UInt32 hash2Value;
SKIP_HEADER(3)
HASH3_CALC;
curMatch = p->hash[kFix3HashSize + hashValue];
p->hash[hash2Value] =
p->hash[kFix3HashSize + hashValue] = p->pos;
SKIP_FOOTER
}
while (--num != 0);
}
void Bt4_MatchFinder_Skip(CMatchFinder *p, UInt32 num)
{
do
{
UInt32 hash2Value, hash3Value;
SKIP_HEADER(4)
HASH4_CALC;
curMatch = p->hash[kFix4HashSize + hashValue];
p->hash[ hash2Value] =
p->hash[kFix3HashSize + hash3Value] = p->pos;
p->hash[kFix4HashSize + hashValue] = p->pos;
SKIP_FOOTER
}
while (--num != 0);
}
void Hc4_MatchFinder_Skip(CMatchFinder *p, UInt32 num)
{
do
{
UInt32 hash2Value, hash3Value;
SKIP_HEADER(4)
HASH4_CALC;
curMatch = p->hash[kFix4HashSize + hashValue];
p->hash[ hash2Value] =
p->hash[kFix3HashSize + hash3Value] =
p->hash[kFix4HashSize + hashValue] = 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[hashValue];
p->hash[hashValue] = 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->GetIndexByte = (Mf_GetIndexByte_Func)MatchFinder_GetIndexByte;
vTable->GetNumAvailableBytes = (Mf_GetNumAvailableBytes_Func)MatchFinder_GetNumAvailableBytes;
vTable->GetPointerToCurrentPos = (Mf_GetPointerToCurrentPos_Func)MatchFinder_GetPointerToCurrentPos;
if (!p->btMode)
{
vTable->GetMatches = (Mf_GetMatches_Func)Hc4_MatchFinder_GetMatches;
vTable->Skip = (Mf_Skip_Func)Hc4_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
{
vTable->GetMatches = (Mf_GetMatches_Func)Bt4_MatchFinder_GetMatches;
vTable->Skip = (Mf_Skip_Func)Bt4_MatchFinder_Skip;
}
}
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