[mirror_edk2.git] / IntelFrameworkModulePkg / Library / LzmaCustomDecompressLib / Sdk / C / LzFind.c

/* LzFind.c -- Match finder for LZ algorithms\r
2015-10-15 : Igor Pavlov : Public domain */\r
\r
#include "Precomp.h"\r
\r
#ifndef EFIAPI\r
#include <string.h>\r
#endif\r
\r
#include "LzFind.h"\r
#include "LzHash.h"\r
\r
#define kEmptyHashValue 0\r
#define kMaxValForNormalize ((UInt32)0xFFFFFFFF)\r
#define kNormalizeStepMin (1 << 10) /* it must be power of 2 */\r
#define kNormalizeMask (~(UInt32)(kNormalizeStepMin - 1))\r
#define kMaxHistorySize ((UInt32)7 << 29)\r
\r
#define kStartMaxLen 3\r
\r
static void LzInWindow_Free(CMatchFinder *p, ISzAlloc *alloc)\r
{\r
  if (!p->directInput)\r
  {\r
    alloc->Free(alloc, p->bufferBase);\r
    p->bufferBase = NULL;\r
  }\r
}\r
\r
/* keepSizeBefore + keepSizeAfter + keepSizeReserv must be < 4G) */\r
\r
static int LzInWindow_Create(CMatchFinder *p, UInt32 keepSizeReserv, ISzAlloc *alloc)\r
{\r
  UInt32 blockSize = p->keepSizeBefore + p->keepSizeAfter + keepSizeReserv;\r
  if (p->directInput)\r
  {\r
    p->blockSize = blockSize;\r
    return 1;\r
  }\r
  if (!p->bufferBase || p->blockSize != blockSize)\r
  {\r
    LzInWindow_Free(p, alloc);\r
    p->blockSize = blockSize;\r
    p->bufferBase = (Byte *)alloc->Alloc(alloc, (size_t)blockSize);\r
  }\r
  return (p->bufferBase != NULL);\r
}\r
\r
Byte *MatchFinder_GetPointerToCurrentPos(CMatchFinder *p) { return p->buffer; }\r
\r
UInt32 MatchFinder_GetNumAvailableBytes(CMatchFinder *p) { return p->streamPos - p->pos; }\r
\r
void MatchFinder_ReduceOffsets(CMatchFinder *p, UInt32 subValue)\r
{\r
  p->posLimit -= subValue;\r
  p->pos -= subValue;\r
  p->streamPos -= subValue;\r
}\r
\r
static void MatchFinder_ReadBlock(CMatchFinder *p)\r
{\r
  if (p->streamEndWasReached || p->result != SZ_OK)\r
    return;\r
\r
  /* We use (p->streamPos - p->pos) value. (p->streamPos < p->pos) is allowed. */\r
\r
  if (p->directInput)\r
  {\r
    UInt32 curSize = 0xFFFFFFFF - (p->streamPos - p->pos);\r
    if (curSize > p->directInputRem)\r
      curSize = (UInt32)p->directInputRem;\r
    p->directInputRem -= curSize;\r
    p->streamPos += curSize;\r
    if (p->directInputRem == 0)\r
      p->streamEndWasReached = 1;\r
    return;\r
  }\r
  \r
  for (;;)\r
  {\r
    Byte *dest = p->buffer + (p->streamPos - p->pos);\r
    size_t size = (p->bufferBase + p->blockSize - dest);\r
    if (size == 0)\r
      return;\r
\r
    p->result = p->stream->Read(p->stream, dest, &size);\r
    if (p->result != SZ_OK)\r
      return;\r
    if (size == 0)\r
    {\r
      p->streamEndWasReached = 1;\r
      return;\r
    }\r
    p->streamPos += (UInt32)size;\r
    if (p->streamPos - p->pos > p->keepSizeAfter)\r
      return;\r
  }\r
}\r
\r
void MatchFinder_MoveBlock(CMatchFinder *p)\r
{\r
  memmove(p->bufferBase,\r
      p->buffer - p->keepSizeBefore,\r
      (size_t)(p->streamPos - p->pos) + p->keepSizeBefore);\r
  p->buffer = p->bufferBase + p->keepSizeBefore;\r
}\r
\r
int MatchFinder_NeedMove(CMatchFinder *p)\r
{\r
  if (p->directInput)\r
    return 0;\r
  /* if (p->streamEndWasReached) return 0; */\r
  return ((size_t)(p->bufferBase + p->blockSize - p->buffer) <= p->keepSizeAfter);\r
}\r
\r
void MatchFinder_ReadIfRequired(CMatchFinder *p)\r
{\r
  if (p->streamEndWasReached)\r
    return;\r
  if (p->keepSizeAfter >= p->streamPos - p->pos)\r
    MatchFinder_ReadBlock(p);\r
}\r
\r
static void MatchFinder_CheckAndMoveAndRead(CMatchFinder *p)\r
{\r
  if (MatchFinder_NeedMove(p))\r
    MatchFinder_MoveBlock(p);\r
  MatchFinder_ReadBlock(p);\r
}\r
\r
static void MatchFinder_SetDefaultSettings(CMatchFinder *p)\r
{\r
  p->cutValue = 32;\r
  p->btMode = 1;\r
  p->numHashBytes = 4;\r
  p->bigHash = 0;\r
}\r
\r
#define kCrcPoly 0xEDB88320\r
\r
void MatchFinder_Construct(CMatchFinder *p)\r
{\r
  UInt32 i;\r
  p->bufferBase = NULL;\r
  p->directInput = 0;\r
  p->hash = NULL;\r
  MatchFinder_SetDefaultSettings(p);\r
\r
  for (i = 0; i < 256; i++)\r
  {\r
    UInt32 r = i;\r
    unsigned j;\r
    for (j = 0; j < 8; j++)\r
      r = (r >> 1) ^ (kCrcPoly & ~((r & 1) - 1));\r
    p->crc[i] = r;\r
  }\r
}\r
\r
static void MatchFinder_FreeThisClassMemory(CMatchFinder *p, ISzAlloc *alloc)\r
{\r
  alloc->Free(alloc, p->hash);\r
  p->hash = NULL;\r
}\r
\r
void MatchFinder_Free(CMatchFinder *p, ISzAlloc *alloc)\r
{\r
  MatchFinder_FreeThisClassMemory(p, alloc);\r
  LzInWindow_Free(p, alloc);\r
}\r
\r
static CLzRef* AllocRefs(size_t num, ISzAlloc *alloc)\r
{\r
  size_t sizeInBytes = (size_t)num * sizeof(CLzRef);\r
  if (sizeInBytes / sizeof(CLzRef) != num)\r
    return NULL;\r
  return (CLzRef *)alloc->Alloc(alloc, sizeInBytes);\r
}\r
\r
int MatchFinder_Create(CMatchFinder *p, UInt32 historySize,\r
    UInt32 keepAddBufferBefore, UInt32 matchMaxLen, UInt32 keepAddBufferAfter,\r
    ISzAlloc *alloc)\r
{\r
  UInt32 sizeReserv;\r
  \r
  if (historySize > kMaxHistorySize)\r
  {\r
    MatchFinder_Free(p, alloc);\r
    return 0;\r
  }\r
  \r
  sizeReserv = historySize >> 1;\r
       if (historySize >= ((UInt32)3 << 30)) sizeReserv = historySize >> 3;\r
  else if (historySize >= ((UInt32)2 << 30)) sizeReserv = historySize >> 2;\r
  \r
  sizeReserv += (keepAddBufferBefore + matchMaxLen + keepAddBufferAfter) / 2 + (1 << 19);\r
\r
  p->keepSizeBefore = historySize + keepAddBufferBefore + 1;\r
  p->keepSizeAfter = matchMaxLen + keepAddBufferAfter;\r
  \r
  /* we need one additional byte, since we use MoveBlock after pos++ and before dictionary using */\r
  \r
  if (LzInWindow_Create(p, sizeReserv, alloc))\r
  {\r
    UInt32 newCyclicBufferSize = historySize + 1;\r
    UInt32 hs;\r
    p->matchMaxLen = matchMaxLen;\r
    {\r
      p->fixedHashSize = 0;\r
      if (p->numHashBytes == 2)\r
        hs = (1 << 16) - 1;\r
      else\r
      {\r
        hs = historySize - 1;\r
        hs |= (hs >> 1);\r
        hs |= (hs >> 2);\r
        hs |= (hs >> 4);\r
        hs |= (hs >> 8);\r
        hs >>= 1;\r
        hs |= 0xFFFF; /* don't change it! It's required for Deflate */\r
        if (hs > (1 << 24))\r
        {\r
          if (p->numHashBytes == 3)\r
            hs = (1 << 24) - 1;\r
          else\r
            hs >>= 1;\r
          /* if (bigHash) mode, GetHeads4b() in LzFindMt.c needs (hs >= ((1 << 24) - 1))) */\r
        }\r
      }\r
      p->hashMask = hs;\r
      hs++;\r
      if (p->numHashBytes > 2) p->fixedHashSize += kHash2Size;\r
      if (p->numHashBytes > 3) p->fixedHashSize += kHash3Size;\r
      if (p->numHashBytes > 4) p->fixedHashSize += kHash4Size;\r
      hs += p->fixedHashSize;\r
    }\r
\r
    {\r
      size_t newSize;\r
      size_t numSons;\r
      p->historySize = historySize;\r
      p->hashSizeSum = hs;\r
      p->cyclicBufferSize = newCyclicBufferSize;\r
      \r
      numSons = newCyclicBufferSize;\r
      if (p->btMode)\r
        numSons <<= 1;\r
      newSize = hs + numSons;\r
\r
      if (p->hash && p->numRefs == newSize)\r
        return 1;\r
      \r
      MatchFinder_FreeThisClassMemory(p, alloc);\r
      p->numRefs = newSize;\r
      p->hash = AllocRefs(newSize, alloc);\r
      \r
      if (p->hash)\r
      {\r
        p->son = p->hash + p->hashSizeSum;\r
        return 1;\r
      }\r
    }\r
  }\r
\r
  MatchFinder_Free(p, alloc);\r
  return 0;\r
}\r
\r
static void MatchFinder_SetLimits(CMatchFinder *p)\r
{\r
  UInt32 limit = kMaxValForNormalize - p->pos;\r
  UInt32 limit2 = p->cyclicBufferSize - p->cyclicBufferPos;\r
  \r
  if (limit2 < limit)\r
    limit = limit2;\r
  limit2 = p->streamPos - p->pos;\r
  \r
  if (limit2 <= p->keepSizeAfter)\r
  {\r
    if (limit2 > 0)\r
      limit2 = 1;\r
  }\r
  else\r
    limit2 -= p->keepSizeAfter;\r
  \r
  if (limit2 < limit)\r
    limit = limit2;\r
  \r
  {\r
    UInt32 lenLimit = p->streamPos - p->pos;\r
    if (lenLimit > p->matchMaxLen)\r
      lenLimit = p->matchMaxLen;\r
    p->lenLimit = lenLimit;\r
  }\r
  p->posLimit = p->pos + limit;\r
}\r
\r
void MatchFinder_Init_2(CMatchFinder *p, int readData)\r
{\r
  UInt32 i;\r
  UInt32 *hash = p->hash;\r
  UInt32 num = p->hashSizeSum;\r
  for (i = 0; i < num; i++)\r
    hash[i] = kEmptyHashValue;\r
  \r
  p->cyclicBufferPos = 0;\r
  p->buffer = p->bufferBase;\r
  p->pos = p->streamPos = p->cyclicBufferSize;\r
  p->result = SZ_OK;\r
  p->streamEndWasReached = 0;\r
  \r
  if (readData)\r
    MatchFinder_ReadBlock(p);\r
  \r
  MatchFinder_SetLimits(p);\r
}\r
\r
void MatchFinder_Init(CMatchFinder *p)\r
{\r
  MatchFinder_Init_2(p, True);\r
}\r
  \r
static UInt32 MatchFinder_GetSubValue(CMatchFinder *p)\r
{\r
  return (p->pos - p->historySize - 1) & kNormalizeMask;\r
}\r
\r
void MatchFinder_Normalize3(UInt32 subValue, CLzRef *items, size_t numItems)\r
{\r
  size_t i;\r
  for (i = 0; i < numItems; i++)\r
  {\r
    UInt32 value = items[i];\r
    if (value <= subValue)\r
      value = kEmptyHashValue;\r
    else\r
      value -= subValue;\r
    items[i] = value;\r
  }\r
}\r
\r
static void MatchFinder_Normalize(CMatchFinder *p)\r
{\r
  UInt32 subValue = MatchFinder_GetSubValue(p);\r
  MatchFinder_Normalize3(subValue, p->hash, p->numRefs);\r
  MatchFinder_ReduceOffsets(p, subValue);\r
}\r
\r
static void MatchFinder_CheckLimits(CMatchFinder *p)\r
{\r
  if (p->pos == kMaxValForNormalize)\r
    MatchFinder_Normalize(p);\r
  if (!p->streamEndWasReached && p->keepSizeAfter == p->streamPos - p->pos)\r
    MatchFinder_CheckAndMoveAndRead(p);\r
  if (p->cyclicBufferPos == p->cyclicBufferSize)\r
    p->cyclicBufferPos = 0;\r
  MatchFinder_SetLimits(p);\r
}\r
\r
static UInt32 * Hc_GetMatchesSpec(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *cur, CLzRef *son,\r
    UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 cutValue,\r
    UInt32 *distances, UInt32 maxLen)\r
{\r
  son[_cyclicBufferPos] = curMatch;\r
  for (;;)\r
  {\r
    UInt32 delta = pos - curMatch;\r
    if (cutValue-- == 0 || delta >= _cyclicBufferSize)\r
      return distances;\r
    {\r
      const Byte *pb = cur - delta;\r
      curMatch = son[_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)];\r
      if (pb[maxLen] == cur[maxLen] && *pb == *cur)\r
      {\r
        UInt32 len = 0;\r
        while (++len != lenLimit)\r
          if (pb[len] != cur[len])\r
            break;\r
        if (maxLen < len)\r
        {\r
          *distances++ = maxLen = len;\r
          *distances++ = delta - 1;\r
          if (len == lenLimit)\r
            return distances;\r
        }\r
      }\r
    }\r
  }\r
}\r
\r
UInt32 * GetMatchesSpec1(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *cur, CLzRef *son,\r
    UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 cutValue,\r
    UInt32 *distances, UInt32 maxLen)\r
{\r
  CLzRef *ptr0 = son + (_cyclicBufferPos << 1) + 1;\r
  CLzRef *ptr1 = son + (_cyclicBufferPos << 1);\r
  UInt32 len0 = 0, len1 = 0;\r
  for (;;)\r
  {\r
    UInt32 delta = pos - curMatch;\r
    if (cutValue-- == 0 || delta >= _cyclicBufferSize)\r
    {\r
      *ptr0 = *ptr1 = kEmptyHashValue;\r
      return distances;\r
    }\r
    {\r
      CLzRef *pair = son + ((_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)) << 1);\r
      const Byte *pb = cur - delta;\r
      UInt32 len = (len0 < len1 ? len0 : len1);\r
      if (pb[len] == cur[len])\r
      {\r
        if (++len != lenLimit && pb[len] == cur[len])\r
          while (++len != lenLimit)\r
            if (pb[len] != cur[len])\r
              break;\r
        if (maxLen < len)\r
        {\r
          *distances++ = maxLen = len;\r
          *distances++ = delta - 1;\r
          if (len == lenLimit)\r
          {\r
            *ptr1 = pair[0];\r
            *ptr0 = pair[1];\r
            return distances;\r
          }\r
        }\r
      }\r
      if (pb[len] < cur[len])\r
      {\r
        *ptr1 = curMatch;\r
        ptr1 = pair + 1;\r
        curMatch = *ptr1;\r
        len1 = len;\r
      }\r
      else\r
      {\r
        *ptr0 = curMatch;\r
        ptr0 = pair;\r
        curMatch = *ptr0;\r
        len0 = len;\r
      }\r
    }\r
  }\r
}\r
\r
static void SkipMatchesSpec(UInt32 lenLimit, UInt32 curMatch, UInt32 pos, const Byte *cur, CLzRef *son,\r
    UInt32 _cyclicBufferPos, UInt32 _cyclicBufferSize, UInt32 cutValue)\r
{\r
  CLzRef *ptr0 = son + (_cyclicBufferPos << 1) + 1;\r
  CLzRef *ptr1 = son + (_cyclicBufferPos << 1);\r
  UInt32 len0 = 0, len1 = 0;\r
  for (;;)\r
  {\r
    UInt32 delta = pos - curMatch;\r
    if (cutValue-- == 0 || delta >= _cyclicBufferSize)\r
    {\r
      *ptr0 = *ptr1 = kEmptyHashValue;\r
      return;\r
    }\r
    {\r
      CLzRef *pair = son + ((_cyclicBufferPos - delta + ((delta > _cyclicBufferPos) ? _cyclicBufferSize : 0)) << 1);\r
      const Byte *pb = cur - delta;\r
      UInt32 len = (len0 < len1 ? len0 : len1);\r
      if (pb[len] == cur[len])\r
      {\r
        while (++len != lenLimit)\r
          if (pb[len] != cur[len])\r
            break;\r
        {\r
          if (len == lenLimit)\r
          {\r
            *ptr1 = pair[0];\r
            *ptr0 = pair[1];\r
            return;\r
          }\r
        }\r
      }\r
      if (pb[len] < cur[len])\r
      {\r
        *ptr1 = curMatch;\r
        ptr1 = pair + 1;\r
        curMatch = *ptr1;\r
        len1 = len;\r
      }\r
      else\r
      {\r
        *ptr0 = curMatch;\r
        ptr0 = pair;\r
        curMatch = *ptr0;\r
        len0 = len;\r
      }\r
    }\r
  }\r
}\r
\r
#define MOVE_POS \\r
  ++p->cyclicBufferPos; \\r
  p->buffer++; \\r
  if (++p->pos == p->posLimit) MatchFinder_CheckLimits(p);\r
\r
#define MOVE_POS_RET MOVE_POS return offset;\r
\r
static void MatchFinder_MovePos(CMatchFinder *p) { MOVE_POS; }\r
\r
#define GET_MATCHES_HEADER2(minLen, ret_op) \\r
  UInt32 lenLimit; UInt32 hv; const Byte *cur; UInt32 curMatch; \\r
  lenLimit = p->lenLimit; { if (lenLimit < minLen) { MatchFinder_MovePos(p); ret_op; }} \\r
  cur = p->buffer;\r
\r
#define GET_MATCHES_HEADER(minLen) GET_MATCHES_HEADER2(minLen, return 0)\r
#define SKIP_HEADER(minLen)        GET_MATCHES_HEADER2(minLen, continue)\r
\r
#define MF_PARAMS(p) p->pos, p->buffer, p->son, p->cyclicBufferPos, p->cyclicBufferSize, p->cutValue\r
\r
#define GET_MATCHES_FOOTER(offset, maxLen) \\r
  offset = (UInt32)(GetMatchesSpec1(lenLimit, curMatch, MF_PARAMS(p), \\r
  distances + offset, maxLen) - distances); MOVE_POS_RET;\r
\r
#define SKIP_FOOTER \\r
  SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p)); MOVE_POS;\r
\r
#define UPDATE_maxLen { \\r
    ptrdiff_t diff = (ptrdiff_t)0 - d2; \\r
    const Byte *c = cur + maxLen; \\r
    const Byte *lim = cur + lenLimit; \\r
    for (; c != lim; c++) if (*(c + diff) != *c) break; \\r
    maxLen = (UInt32)(c - cur); }\r
\r
static UInt32 Bt2_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 offset;\r
  GET_MATCHES_HEADER(2)\r
  HASH2_CALC;\r
  curMatch = p->hash[hv];\r
  p->hash[hv] = p->pos;\r
  offset = 0;\r
  GET_MATCHES_FOOTER(offset, 1)\r
}\r
\r
UInt32 Bt3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 offset;\r
  GET_MATCHES_HEADER(3)\r
  HASH_ZIP_CALC;\r
  curMatch = p->hash[hv];\r
  p->hash[hv] = p->pos;\r
  offset = 0;\r
  GET_MATCHES_FOOTER(offset, 2)\r
}\r
\r
static UInt32 Bt3_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 h2, d2, maxLen, offset, pos;\r
  UInt32 *hash;\r
  GET_MATCHES_HEADER(3)\r
\r
  HASH3_CALC;\r
\r
  hash = p->hash;\r
  pos = p->pos;\r
\r
  d2 = pos - hash[h2];\r
\r
  curMatch = hash[kFix3HashSize + hv];\r
  \r
  hash[h2] = pos;\r
  hash[kFix3HashSize + hv] = pos;\r
\r
  maxLen = 2;\r
  offset = 0;\r
\r
  if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)\r
  {\r
    UPDATE_maxLen\r
    distances[0] = maxLen;\r
    distances[1] = d2 - 1;\r
    offset = 2;\r
    if (maxLen == lenLimit)\r
    {\r
      SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p));\r
      MOVE_POS_RET;\r
    }\r
  }\r
  \r
  GET_MATCHES_FOOTER(offset, maxLen)\r
}\r
\r
static UInt32 Bt4_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 h2, h3, d2, d3, maxLen, offset, pos;\r
  UInt32 *hash;\r
  GET_MATCHES_HEADER(4)\r
\r
  HASH4_CALC;\r
\r
  hash = p->hash;\r
  pos = p->pos;\r
\r
  d2 = pos - hash[                h2];\r
  d3 = pos - hash[kFix3HashSize + h3];\r
\r
  curMatch = hash[kFix4HashSize + hv];\r
\r
  hash[                h2] = pos;\r
  hash[kFix3HashSize + h3] = pos;\r
  hash[kFix4HashSize + hv] = pos;\r
\r
  maxLen = 0;\r
  offset = 0;\r
  \r
  if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)\r
  {\r
    distances[0] = maxLen = 2;\r
    distances[1] = d2 - 1;\r
    offset = 2;\r
  }\r
  \r
  if (d2 != d3 && d3 < p->cyclicBufferSize && *(cur - d3) == *cur)\r
  {\r
    maxLen = 3;\r
    distances[offset + 1] = d3 - 1;\r
    offset += 2;\r
    d2 = d3;\r
  }\r
  \r
  if (offset != 0)\r
  {\r
    UPDATE_maxLen\r
    distances[offset - 2] = maxLen;\r
    if (maxLen == lenLimit)\r
    {\r
      SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p));\r
      MOVE_POS_RET;\r
    }\r
  }\r
  \r
  if (maxLen < 3)\r
    maxLen = 3;\r
  \r
  GET_MATCHES_FOOTER(offset, maxLen)\r
}\r
\r
/*\r
static UInt32 Bt5_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 h2, h3, h4, d2, d3, d4, maxLen, offset, pos;\r
  UInt32 *hash;\r
  GET_MATCHES_HEADER(5)\r
\r
  HASH5_CALC;\r
\r
  hash = p->hash;\r
  pos = p->pos;\r
\r
  d2 = pos - hash[                h2];\r
  d3 = pos - hash[kFix3HashSize + h3];\r
  d4 = pos - hash[kFix4HashSize + h4];\r
\r
  curMatch = hash[kFix5HashSize + hv];\r
\r
  hash[                h2] = pos;\r
  hash[kFix3HashSize + h3] = pos;\r
  hash[kFix4HashSize + h4] = pos;\r
  hash[kFix5HashSize + hv] = pos;\r
\r
  maxLen = 0;\r
  offset = 0;\r
\r
  if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)\r
  {\r
    distances[0] = maxLen = 2;\r
    distances[1] = d2 - 1;\r
    offset = 2;\r
    if (*(cur - d2 + 2) == cur[2])\r
      distances[0] = maxLen = 3;\r
    else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)\r
    {\r
      distances[2] = maxLen = 3;\r
      distances[3] = d3 - 1;\r
      offset = 4;\r
      d2 = d3;\r
    }\r
  }\r
  else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)\r
  {\r
    distances[0] = maxLen = 3;\r
    distances[1] = d3 - 1;\r
    offset = 2;\r
    d2 = d3;\r
  }\r
  \r
  if (d2 != d4 && d4 < p->cyclicBufferSize\r
      && *(cur - d4) == *cur\r
      && *(cur - d4 + 3) == *(cur + 3))\r
  {\r
    maxLen = 4;\r
    distances[offset + 1] = d4 - 1;\r
    offset += 2;\r
    d2 = d4;\r
  }\r
  \r
  if (offset != 0)\r
  {\r
    UPDATE_maxLen\r
    distances[offset - 2] = maxLen;\r
    if (maxLen == lenLimit)\r
    {\r
      SkipMatchesSpec(lenLimit, curMatch, MF_PARAMS(p));\r
      MOVE_POS_RET;\r
    }\r
  }\r
\r
  if (maxLen < 4)\r
    maxLen = 4;\r
  \r
  GET_MATCHES_FOOTER(offset, maxLen)\r
}\r
*/\r
\r
static UInt32 Hc4_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 h2, h3, d2, d3, maxLen, offset, pos;\r
  UInt32 *hash;\r
  GET_MATCHES_HEADER(4)\r
\r
  HASH4_CALC;\r
\r
  hash = p->hash;\r
  pos = p->pos;\r
  \r
  d2 = pos - hash[                h2];\r
  d3 = pos - hash[kFix3HashSize + h3];\r
  \r
  curMatch = hash[kFix4HashSize + hv];\r
\r
  hash[                h2] = pos;\r
  hash[kFix3HashSize + h3] = pos;\r
  hash[kFix4HashSize + hv] = pos;\r
\r
  maxLen = 0;\r
  offset = 0;\r
\r
  if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)\r
  {\r
    distances[0] = maxLen = 2;\r
    distances[1] = d2 - 1;\r
    offset = 2;\r
  }\r
  \r
  if (d2 != d3 && d3 < p->cyclicBufferSize && *(cur - d3) == *cur)\r
  {\r
    maxLen = 3;\r
    distances[offset + 1] = d3 - 1;\r
    offset += 2;\r
    d2 = d3;\r
  }\r
  \r
  if (offset != 0)\r
  {\r
    UPDATE_maxLen\r
    distances[offset - 2] = maxLen;\r
    if (maxLen == lenLimit)\r
    {\r
      p->son[p->cyclicBufferPos] = curMatch;\r
      MOVE_POS_RET;\r
    }\r
  }\r
  \r
  if (maxLen < 3)\r
    maxLen = 3;\r
\r
  offset = (UInt32)(Hc_GetMatchesSpec(lenLimit, curMatch, MF_PARAMS(p),\r
      distances + offset, maxLen) - (distances));\r
  MOVE_POS_RET\r
}\r
\r
/*\r
static UInt32 Hc5_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 h2, h3, h4, d2, d3, d4, maxLen, offset, pos\r
  UInt32 *hash;\r
  GET_MATCHES_HEADER(5)\r
\r
  HASH5_CALC;\r
\r
  hash = p->hash;\r
  pos = p->pos;\r
  \r
  d2 = pos - hash[                h2];\r
  d3 = pos - hash[kFix3HashSize + h3];\r
  d4 = pos - hash[kFix4HashSize + h4];\r
\r
  curMatch = hash[kFix5HashSize + hv];\r
\r
  hash[                h2] = pos;\r
  hash[kFix3HashSize + h3] = pos;\r
  hash[kFix4HashSize + h4] = pos;\r
  hash[kFix5HashSize + hv] = pos;\r
\r
  maxLen = 0;\r
  offset = 0;\r
\r
  if (d2 < p->cyclicBufferSize && *(cur - d2) == *cur)\r
  {\r
    distances[0] = maxLen = 2;\r
    distances[1] = d2 - 1;\r
    offset = 2;\r
    if (*(cur - d2 + 2) == cur[2])\r
      distances[0] = maxLen = 3;\r
    else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)\r
    {\r
      distances[2] = maxLen = 3;\r
      distances[3] = d3 - 1;\r
      offset = 4;\r
      d2 = d3;\r
    }\r
  }\r
  else if (d3 < p->cyclicBufferSize && *(cur - d3) == *cur)\r
  {\r
    distances[0] = maxLen = 3;\r
    distances[1] = d3 - 1;\r
    offset = 2;\r
    d2 = d3;\r
  }\r
  \r
  if (d2 != d4 && d4 < p->cyclicBufferSize\r
      && *(cur - d4) == *cur\r
      && *(cur - d4 + 3) == *(cur + 3))\r
  {\r
    maxLen = 4;\r
    distances[offset + 1] = d4 - 1;\r
    offset += 2;\r
    d2 = d4;\r
  }\r
  \r
  if (offset != 0)\r
  {\r
    UPDATE_maxLen\r
    distances[offset - 2] = maxLen;\r
    if (maxLen == lenLimit)\r
    {\r
      p->son[p->cyclicBufferPos] = curMatch;\r
      MOVE_POS_RET;\r
    }\r
  }\r
  \r
  if (maxLen < 4)\r
    maxLen = 4;\r
\r
  offset = (UInt32)(Hc_GetMatchesSpec(lenLimit, curMatch, MF_PARAMS(p),\r
      distances + offset, maxLen) - (distances));\r
  MOVE_POS_RET\r
}\r
*/\r
\r
UInt32 Hc3Zip_MatchFinder_GetMatches(CMatchFinder *p, UInt32 *distances)\r
{\r
  UInt32 offset;\r
  GET_MATCHES_HEADER(3)\r
  HASH_ZIP_CALC;\r
  curMatch = p->hash[hv];\r
  p->hash[hv] = p->pos;\r
  offset = (UInt32)(Hc_GetMatchesSpec(lenLimit, curMatch, MF_PARAMS(p),\r
      distances, 2) - (distances));\r
  MOVE_POS_RET\r
}\r
\r
static void Bt2_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    SKIP_HEADER(2)\r
    HASH2_CALC;\r
    curMatch = p->hash[hv];\r
    p->hash[hv] = p->pos;\r
    SKIP_FOOTER\r
  }\r
  while (--num != 0);\r
}\r
\r
void Bt3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    SKIP_HEADER(3)\r
    HASH_ZIP_CALC;\r
    curMatch = p->hash[hv];\r
    p->hash[hv] = p->pos;\r
    SKIP_FOOTER\r
  }\r
  while (--num != 0);\r
}\r
\r
static void Bt3_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    UInt32 h2;\r
    UInt32 *hash;\r
    SKIP_HEADER(3)\r
    HASH3_CALC;\r
    hash = p->hash;\r
    curMatch = hash[kFix3HashSize + hv];\r
    hash[h2] =\r
    hash[kFix3HashSize + hv] = p->pos;\r
    SKIP_FOOTER\r
  }\r
  while (--num != 0);\r
}\r
\r
static void Bt4_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    UInt32 h2, h3;\r
    UInt32 *hash;\r
    SKIP_HEADER(4)\r
    HASH4_CALC;\r
    hash = p->hash;\r
    curMatch = hash[kFix4HashSize + hv];\r
    hash[                h2] =\r
    hash[kFix3HashSize + h3] =\r
    hash[kFix4HashSize + hv] = p->pos;\r
    SKIP_FOOTER\r
  }\r
  while (--num != 0);\r
}\r
\r
/*\r
static void Bt5_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    UInt32 h2, h3, h4;\r
    UInt32 *hash;\r
    SKIP_HEADER(5)\r
    HASH5_CALC;\r
    hash = p->hash;\r
    curMatch = hash[kFix5HashSize + hv];\r
    hash[                h2] =\r
    hash[kFix3HashSize + h3] =\r
    hash[kFix4HashSize + h4] =\r
    hash[kFix5HashSize + hv] = p->pos;\r
    SKIP_FOOTER\r
  }\r
  while (--num != 0);\r
}\r
*/\r
\r
static void Hc4_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    UInt32 h2, h3;\r
    UInt32 *hash;\r
    SKIP_HEADER(4)\r
    HASH4_CALC;\r
    hash = p->hash;\r
    curMatch = hash[kFix4HashSize + hv];\r
    hash[                h2] =\r
    hash[kFix3HashSize + h3] =\r
    hash[kFix4HashSize + hv] = p->pos;\r
    p->son[p->cyclicBufferPos] = curMatch;\r
    MOVE_POS\r
  }\r
  while (--num != 0);\r
}\r
\r
/*\r
static void Hc5_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    UInt32 h2, h3, h4;\r
    UInt32 *hash;\r
    SKIP_HEADER(5)\r
    HASH5_CALC;\r
    hash = p->hash;\r
    curMatch = p->hash[kFix5HashSize + hv];\r
    hash[                h2] =\r
    hash[kFix3HashSize + h3] =\r
    hash[kFix4HashSize + h4] =\r
    hash[kFix5HashSize + hv] = p->pos;\r
    p->son[p->cyclicBufferPos] = curMatch;\r
    MOVE_POS\r
  }\r
  while (--num != 0);\r
}\r
*/\r
\r
void Hc3Zip_MatchFinder_Skip(CMatchFinder *p, UInt32 num)\r
{\r
  do\r
  {\r
    SKIP_HEADER(3)\r
    HASH_ZIP_CALC;\r
    curMatch = p->hash[hv];\r
    p->hash[hv] = p->pos;\r
    p->son[p->cyclicBufferPos] = curMatch;\r
    MOVE_POS\r
  }\r
  while (--num != 0);\r
}\r
\r
void MatchFinder_CreateVTable(CMatchFinder *p, IMatchFinder *vTable)\r
{\r
  vTable->Init = (Mf_Init_Func)MatchFinder_Init;\r
  vTable->GetNumAvailableBytes = (Mf_GetNumAvailableBytes_Func)MatchFinder_GetNumAvailableBytes;\r
  vTable->GetPointerToCurrentPos = (Mf_GetPointerToCurrentPos_Func)MatchFinder_GetPointerToCurrentPos;\r
  if (!p->btMode)\r
  {\r
    /* if (p->numHashBytes <= 4) */\r
    {\r
      vTable->GetMatches = (Mf_GetMatches_Func)Hc4_MatchFinder_GetMatches;\r
      vTable->Skip = (Mf_Skip_Func)Hc4_MatchFinder_Skip;\r
    }\r
    /*\r
    else\r
    {\r
      vTable->GetMatches = (Mf_GetMatches_Func)Hc5_MatchFinder_GetMatches;\r
      vTable->Skip = (Mf_Skip_Func)Hc5_MatchFinder_Skip;\r
    }\r
    */\r
  }\r
  else if (p->numHashBytes == 2)\r
  {\r
    vTable->GetMatches = (Mf_GetMatches_Func)Bt2_MatchFinder_GetMatches;\r
    vTable->Skip = (Mf_Skip_Func)Bt2_MatchFinder_Skip;\r
  }\r
  else if (p->numHashBytes == 3)\r
  {\r
    vTable->GetMatches = (Mf_GetMatches_Func)Bt3_MatchFinder_GetMatches;\r
    vTable->Skip = (Mf_Skip_Func)Bt3_MatchFinder_Skip;\r
  }\r
  else /* if (p->numHashBytes == 4) */\r
  {\r
    vTable->GetMatches = (Mf_GetMatches_Func)Bt4_MatchFinder_GetMatches;\r
    vTable->Skip = (Mf_Skip_Func)Bt4_MatchFinder_Skip;\r
  }\r
  /*\r
  else\r
  {\r
    vTable->GetMatches = (Mf_GetMatches_Func)Bt5_MatchFinder_GetMatches;\r
    vTable->Skip = (Mf_Skip_Func)Bt5_MatchFinder_Skip;\r
  }\r
  */\r
}\r