48 lines
1.7 KiB
JavaScript
48 lines
1.7 KiB
JavaScript
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module.exports = BinaryReader;
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function BinaryReader(buffer, isBigEndian) {
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this.buffer = buffer;
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this.position = 0;
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this.isBigEndian = isBigEndian || false;
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}
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function _read(readLE, readBE, size) {
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return function () {
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var value;
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if (this.isBigEndian)
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value = readBE.call(this.buffer, this.position);
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else
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value = readLE.call(this.buffer, this.position);
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this.position += size;
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return value;
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};
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}
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BinaryReader.prototype.readUInt8 = _read(Buffer.prototype.readUInt8, Buffer.prototype.readUInt8, 1);
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BinaryReader.prototype.readUInt16 = _read(Buffer.prototype.readUInt16LE, Buffer.prototype.readUInt16BE, 2);
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BinaryReader.prototype.readUInt32 = _read(Buffer.prototype.readUInt32LE, Buffer.prototype.readUInt32BE, 4);
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BinaryReader.prototype.readInt8 = _read(Buffer.prototype.readInt8, Buffer.prototype.readInt8, 1);
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BinaryReader.prototype.readInt16 = _read(Buffer.prototype.readInt16LE, Buffer.prototype.readInt16BE, 2);
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BinaryReader.prototype.readInt32 = _read(Buffer.prototype.readInt32LE, Buffer.prototype.readInt32BE, 4);
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BinaryReader.prototype.readFloat = _read(Buffer.prototype.readFloatLE, Buffer.prototype.readFloatBE, 4);
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BinaryReader.prototype.readDouble = _read(Buffer.prototype.readDoubleLE, Buffer.prototype.readDoubleBE, 8);
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BinaryReader.prototype.readVarInt = function () {
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var nextByte,
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result = 0,
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bytesRead = 0;
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do {
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nextByte = this.buffer[this.position + bytesRead];
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result += (nextByte & 0x7F) << (7 * bytesRead);
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bytesRead++;
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} while (nextByte >= 0x80);
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this.position += bytesRead;
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return result;
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};
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