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mobile-query-three-vendor-three.js-loaders-ctm-lzma.js / js



  
  var LZMA = LZMA || {};
  
  LZMA.OutWindow = function(){
    this._windowSize = 0;
  };
  
  LZMA.OutWindow.prototype.create = function(windowSize){
    if ( (!this._buffer) || (this._windowSize !== windowSize) ){
      this._buffer = [];
    }
    this._windowSize = windowSize;
    this._pos = 0;
    this._streamPos = 0;
  };
  
  LZMA.OutWindow.prototype.flush = function(){
    var size = this._pos - this._streamPos;
    if (size !== 0){
      while(size --){
        this._stream.writeByte(this._buffer[this._streamPos ++]);
      }
      if (this._pos >= this._windowSize){
        this._pos = 0;
      }
      this._streamPos = this._pos;
    }
  };
  
  LZMA.OutWindow.prototype.releaseStream = function(){
    this.flush();
    this._stream = null;
  };
  
  LZMA.OutWindow.prototype.setStream = function(stream){
    this.releaseStream();
    this._stream = stream;
  };
  
  LZMA.OutWindow.prototype.init = function(solid){
    if (!solid){
      this._streamPos = 0;
      this._pos = 0;
    }
  };
  
  LZMA.OutWindow.prototype.copyBlock = function(distance, len){
    var pos = this._pos - distance - 1;
    if (pos < 0){
      pos += this._windowSize;
    }
    while(len --){
      if (pos >= this._windowSize){
        pos = 0;
      }
      this._buffer[this._pos ++] = this._buffer[pos ++];
      if (this._pos >= this._windowSize){
        this.flush();
      }
    }
  };
  
  LZMA.OutWindow.prototype.putByte = function(b){
    this._buffer[this._pos ++] = b;
    if (this._pos >= this._windowSize){
      this.flush();
    }
  };
  
  LZMA.OutWindow.prototype.getByte = function(distance){
    var pos = this._pos - distance - 1;
    if (pos < 0){
      pos += this._windowSize;
    }
    return this._buffer[pos];
  };
  
  LZMA.RangeDecoder = function(){
  };
  
  LZMA.RangeDecoder.prototype.setStream = function(stream){
    this._stream = stream;
  };
  
  LZMA.RangeDecoder.prototype.releaseStream = function(){
    this._stream = null;
  };
  
  LZMA.RangeDecoder.prototype.init = function(){
    var i = 5;
  
    this._code = 0;
    this._range = -1;
    
    while(i --){
      this._code = (this._code << 8) | this._stream.readByte();
    }
  };
  
  LZMA.RangeDecoder.prototype.decodeDirectBits = function(numTotalBits){
    var result = 0, i = numTotalBits, t;
  
    while(i --){
      this._range >>>= 1;
      t = (this._code - this._range) >>> 31;
      this._code -= this._range & (t - 1);
      result = (result << 1) | (1 - t);
  
      if ( (this._range & 0xff000000) === 0){
        this._code = (this._code << 8) | this._stream.readByte();
        this._range <<= 8;
      }
    }
  
    return result;
  };
  
  LZMA.RangeDecoder.prototype.decodeBit = function(probs, index){
    var prob = probs[index],
        newBound = (this._range >>> 11) * prob;
  
    if ( (this._code ^ 0x80000000) < (newBound ^ 0x80000000) ){
      this._range = newBound;
      probs[index] += (2048 - prob) >>> 5;
      if ( (this._range & 0xff000000) === 0){
        this._code = (this._code << 8) | this._stream.readByte();
        this._range <<= 8;
      }
      return 0;
    }
  
    this._range -= newBound;
    this._code -= newBound;
    probs[index] -= prob >>> 5;
    if ( (this._range & 0xff000000) === 0){
      this._code = (this._code << 8) | this._stream.readByte();
      this._range <<= 8;
    }
    return 1;
  };
  
  LZMA.initBitModels = function(probs, len){
    while(len --){
      probs[len] = 1024;
    }
  };
  
  LZMA.BitTreeDecoder = function(numBitLevels){
    this._models = [];
    this._numBitLevels = numBitLevels;
  };
  
  LZMA.BitTreeDecoder.prototype.init = function(){
    LZMA.initBitModels(this._models, 1 << this._numBitLevels);
  };
  
  LZMA.BitTreeDecoder.prototype.decode = function(rangeDecoder){
    var m = 1, i = this._numBitLevels;
  
    while(i --){
      m = (m << 1) | rangeDecoder.decodeBit(this._models, m);
    }
    return m - (1 << this._numBitLevels);
  };
  
  LZMA.BitTreeDecoder.prototype.reverseDecode = function(rangeDecoder){
    var m = 1, symbol = 0, i = 0, bit;
  
    for (; i < this._numBitLevels; ++ i){
      bit = rangeDecoder.decodeBit(this._models, m);
      m = (m << 1) | bit;
      symbol |= bit << i;
    }
    return symbol;
  };
  
  LZMA.reverseDecode2 = function(models, startIndex, rangeDecoder, numBitLevels){
    var m = 1, symbol = 0, i = 0, bit;
  
    for (; i < numBitLevels; ++ i){
      bit = rangeDecoder.decodeBit(models, startIndex + m);
      m = (m << 1) | bit;
      symbol |= bit << i;
    }
    return symbol;
  };
  
  LZMA.LenDecoder = function(){
    this._choice = [];
    this._lowCoder = [];
    this._midCoder = [];
    this._highCoder = new LZMA.BitTreeDecoder(8);
    this._numPosStates = 0;
  };
  
  LZMA.LenDecoder.prototype.create = function(numPosStates){
    for (; this._numPosStates < numPosStates; ++ this._numPosStates){
      this._lowCoder[this._numPosStates] = new LZMA.BitTreeDecoder(3);
      this._midCoder[this._numPosStates] = new LZMA.BitTreeDecoder(3);
    }
  };
  
  LZMA.LenDecoder.prototype.init = function(){
    var i = this._numPosStates;
    LZMA.initBitModels(this._choice, 2);
    while(i --){
      this._lowCoder[i].init();
      this._midCoder[i].init();
    }
    this._highCoder.init();
  };
  
  LZMA.LenDecoder.prototype.decode = function(rangeDecoder, posState){
    if (rangeDecoder.decodeBit(this._choice, 0) === 0){
      return this._lowCoder[posState].decode(rangeDecoder);
    }
    if (rangeDecoder.decodeBit(this._choice, 1) === 0){
      return 8 + this._midCoder[posState].decode(rangeDecoder);
    }
    return 16 + this._highCoder.decode(rangeDecoder);
  };
  
  LZMA.Decoder2 = function(){
    this._decoders = [];
  };
  
  LZMA.Decoder2.prototype.init = function(){
    LZMA.initBitModels(this._decoders, 0x300);
  };
  
  LZMA.Decoder2.prototype.decodeNormal = function(rangeDecoder){
    var symbol = 1;
  
    do{
      symbol = (symbol << 1) | rangeDecoder.decodeBit(this._decoders, symbol);
    }while(symbol < 0x100);
  
    return symbol & 0xff;
  };
  
  LZMA.Decoder2.prototype.decodeWithMatchByte = function(rangeDecoder, matchByte){
    var symbol = 1, matchBit, bit;
  
    do{
      matchBit = (matchByte >> 7) & 1;
      matchByte <<= 1;
      bit = rangeDecoder.decodeBit(this._decoders, ( (1 + matchBit) << 8) + symbol);
      symbol = (symbol << 1) | bit;
      if (matchBit !== bit){
        while(symbol < 0x100){
          symbol = (symbol << 1) | rangeDecoder.decodeBit(this._decoders, symbol);
        }
        break;
      }
    }while(symbol < 0x100);
  
    return symbol & 0xff;
  };
  
  LZMA.LiteralDecoder = function(){
  };
  
  LZMA.LiteralDecoder.prototype.create = function(numPosBits, numPrevBits){
    var i;
  
    if (this._coders
      && (this._numPrevBits === numPrevBits)
      && (this._numPosBits === numPosBits) ){
      return;
    }
    this._numPosBits = numPosBits;
    this._posMask = (1 << numPosBits) - 1;
    this._numPrevBits = numPrevBits;
  
    this._coders = [];
  
    i = 1 << (this._numPrevBits + this._numPosBits);
    while(i --){
      this._coders[i] = new LZMA.Decoder2();
    }
  };
  
  LZMA.LiteralDecoder.prototype.init = function(){
    var i = 1 << (this._numPrevBits + this._numPosBits);
    while(i --){
      this._coders[i].init();
    }
  };
  
  LZMA.LiteralDecoder.prototype.getDecoder = function(pos, prevByte){
    return this._coders[( (pos & this._posMask) << this._numPrevBits)
      + ( (prevByte & 0xff) >>> (8 - this._numPrevBits) )];
  };
  
  LZMA.Decoder = function(){
    this._outWindow = new LZMA.OutWindow();
    this._rangeDecoder = new LZMA.RangeDecoder();
    this._isMatchDecoders = [];
    this._isRepDecoders = [];
    this._isRepG0Decoders = [];
    this._isRepG1Decoders = [];
    this._isRepG2Decoders = [];
    this._isRep0LongDecoders = [];
    this._posSlotDecoder = [];
    this._posDecoders = [];
    this._posAlignDecoder = new LZMA.BitTreeDecoder(4);
    this._lenDecoder = new LZMA.LenDecoder();
    this._repLenDecoder = new LZMA.LenDecoder();
    this._literalDecoder = new LZMA.LiteralDecoder();
    this._dictionarySize = -1;
    this._dictionarySizeCheck = -1;
  
    this._posSlotDecoder[0] = new LZMA.BitTreeDecoder(6);
    this._posSlotDecoder[1] = new LZMA.BitTreeDecoder(6);
    this._posSlotDecoder[2] = new LZMA.BitTreeDecoder(6);
    this._posSlotDecoder[3] = new LZMA.BitTreeDecoder(6);
  };
  
  LZMA.Decoder.prototype.setDictionarySize = function(dictionarySize){
    if (dictionarySize < 0){
      return false;
    }
    if (this._dictionarySize !== dictionarySize){
      this._dictionarySize = dictionarySize;
      this._dictionarySizeCheck = Math.max(this._dictionarySize, 1);
      this._outWindow.create( Math.max(this._dictionarySizeCheck, 4096) );
    }
    return true;
  };
  
  LZMA.Decoder.prototype.setLcLpPb = function(lc, lp, pb){
    var numPosStates = 1 << pb;
  
    if (lc > 8 || lp > 4 || pb > 4){
      return false;
    }
  
    this._literalDecoder.create(lp, lc);
  
    this._lenDecoder.create(numPosStates);
    this._repLenDecoder.create(numPosStates);
    this._posStateMask = numPosStates - 1;
  
    return true;
  };
  
  LZMA.Decoder.prototype.init = function(){
    var i = 4;
  
    this._outWindow.init(false);
  
    LZMA.initBitModels(this._isMatchDecoders, 192);
    LZMA.initBitModels(this._isRep0LongDecoders, 192);
    LZMA.initBitModels(this._isRepDecoders, 12);
    LZMA.initBitModels(this._isRepG0Decoders, 12);
    LZMA.initBitModels(this._isRepG1Decoders, 12);
    LZMA.initBitModels(this._isRepG2Decoders, 12);
    LZMA.initBitModels(this._posDecoders, 114);
  
    this._literalDecoder.init();
  
    while(i --){
      this._posSlotDecoder[i].init();
    }
  
    this._lenDecoder.init();
    this._repLenDecoder.init();
    this._posAlignDecoder.init();
    this._rangeDecoder.init();
  };
  
  LZMA.Decoder.prototype.decode = function(inStream, outStream, outSize){
    var state = 0, rep0 = 0, rep1 = 0, rep2 = 0, rep3 = 0, nowPos64 = 0, prevByte = 0,
        posState, decoder2, len, distance, posSlot, numDirectBits;
  
    this._rangeDecoder.setStream(inStream);
    this._outWindow.setStream(outStream);
  
    this.init();
  
    while(outSize < 0 || nowPos64 < outSize){
      posState = nowPos64 & this._posStateMask;
  
      if (this._rangeDecoder.decodeBit(this._isMatchDecoders, (state << 4) + posState) === 0){
        decoder2 = this._literalDecoder.getDecoder(nowPos64 ++, prevByte);
  
        if (state >= 7){
          prevByte = decoder2.decodeWithMatchByte(this._rangeDecoder, this._outWindow.getByte(rep0) );
        }else{
          prevByte = decoder2.decodeNormal(this._rangeDecoder);
        }
        this._outWindow.putByte(prevByte);
  
        state = state < 4? 0: state - (state < 10? 3: 6);
  
      }else{
  
        if (this._rangeDecoder.decodeBit(this._isRepDecoders, state) === 1){
          len = 0;
          if (this._rangeDecoder.decodeBit(this._isRepG0Decoders, state) === 0){
            if (this._rangeDecoder.decodeBit(this._isRep0LongDecoders, (state << 4) + posState) === 0){
              state = state < 7? 9: 11;
              len = 1;
            }
          }else{
            if (this._rangeDecoder.decodeBit(this._isRepG1Decoders, state) === 0){
              distance = rep1;
            }else{
              if (this._rangeDecoder.decodeBit(this._isRepG2Decoders, state) === 0){
                distance = rep2;
              }else{
                distance = rep3;
                rep3 = rep2;
              }
              rep2 = rep1;
            }
            rep1 = rep0;
            rep0 = distance;
          }
          if (len === 0){
            len = 2 + this._repLenDecoder.decode(this._rangeDecoder, posState);
            state = state < 7? 8: 11;
          }
        }else{
          rep3 = rep2;
          rep2 = rep1;
          rep1 = rep0;
  
          len = 2 + this._lenDecoder.decode(this._rangeDecoder, posState);
          state = state < 7? 7: 10;
  
          posSlot = this._posSlotDecoder[len <= 5? len - 2: 3].decode(this._rangeDecoder);
          if (posSlot >= 4){
  
            numDirectBits = (posSlot >> 1) - 1;
            rep0 = (2 | (posSlot & 1) ) << numDirectBits;
  
            if (posSlot < 14){
              rep0 += LZMA.reverseDecode2(this._posDecoders,
                  rep0 - posSlot - 1, this._rangeDecoder, numDirectBits);
            }else{
              rep0 += this._rangeDecoder.decodeDirectBits(numDirectBits - 4) << 4;
              rep0 += this._posAlignDecoder.reverseDecode(this._rangeDecoder);
              if (rep0 < 0){
                if (rep0 === -1){
                  break;
                }
                return false;
              }
            }
          }else{
            rep0 = posSlot;
          }
        }
  
        if (rep0 >= nowPos64 || rep0 >= this._dictionarySizeCheck){
          return false;
        }
  
        this._outWindow.copyBlock(rep0, len);
        nowPos64 += len;
        prevByte = this._outWindow.getByte(0);
      }
    }
  
    this._outWindow.flush();
    this._outWindow.releaseStream();
    this._rangeDecoder.releaseStream();
  
    return true;
  };
  
  LZMA.Decoder.prototype.setDecoderProperties = function(properties){
    var value, lc, lp, pb, dictionarySize;
  
    if (properties.size < 5){
      return false;
    }
  
    value = properties.readByte();
    lc = value % 9;
    value = ~~(value / 9);
    lp = value % 5;
    pb = ~~(value / 5);
  
    if ( !this.setLcLpPb(lc, lp, pb) ){
      return false;
    }
  
    dictionarySize = properties.readByte();
    dictionarySize |= properties.readByte() << 8;
    dictionarySize |= properties.readByte() << 16;
    dictionarySize += properties.readByte() * 16777216;
  
    return this.setDictionarySize(dictionarySize);
  };
  
  LZMA.decompress = function(properties, inStream, outStream, outSize){
    var decoder = new LZMA.Decoder();
  
    if ( !decoder.setDecoderProperties(properties) ){
      throw "Incorrect stream properties";
    }
  
    if ( !decoder.decode(inStream, outStream, outSize) ){
      throw "Error in data stream";
    }
  
    return true;
  };
  


(C) Æliens 04/09/2009

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