binaryreader.js
1.63 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
module.exports = BinaryReader;
function BinaryReader(buffer, isBigEndian) {
this.buffer = buffer;
this.position = 0;
this.isBigEndian = isBigEndian || false;
}
function _read(readLE, readBE, size) {
return function () {
var value;
if (this.isBigEndian)
value = readBE.call(this.buffer, this.position);
else
value = readLE.call(this.buffer, this.position);
this.position += size;
return value;
};
}
BinaryReader.prototype.readUInt8 = _read(Buffer.prototype.readUInt8, Buffer.prototype.readUInt8, 1);
BinaryReader.prototype.readUInt16 = _read(Buffer.prototype.readUInt16LE, Buffer.prototype.readUInt16BE, 2);
BinaryReader.prototype.readUInt32 = _read(Buffer.prototype.readUInt32LE, Buffer.prototype.readUInt32BE, 4);
BinaryReader.prototype.readInt8 = _read(Buffer.prototype.readInt8, Buffer.prototype.readInt8, 1);
BinaryReader.prototype.readInt16 = _read(Buffer.prototype.readInt16LE, Buffer.prototype.readInt16BE, 2);
BinaryReader.prototype.readInt32 = _read(Buffer.prototype.readInt32LE, Buffer.prototype.readInt32BE, 4);
BinaryReader.prototype.readFloat = _read(Buffer.prototype.readFloatLE, Buffer.prototype.readFloatBE, 4);
BinaryReader.prototype.readDouble = _read(Buffer.prototype.readDoubleLE, Buffer.prototype.readDoubleBE, 8);
BinaryReader.prototype.readVarInt = function () {
var nextByte,
result = 0,
bytesRead = 0;
do {
nextByte = this.buffer[this.position + bytesRead];
result += (nextByte & 0x7F) << (7 * bytesRead);
bytesRead++;
} while (nextByte >= 0x80);
this.position += bytesRead;
return result;
};