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Classes for convenient work with binary data
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class BinaryWriter { | |
constructor(buffer = [], offset = 0, littleEndian = true) { | |
this.view = new DataView(new ArrayBuffer(8)); | |
this._buffer = []; | |
this.littleEndian = false; | |
if (Array.isArray(buffer)) { | |
this._buffer = buffer; | |
} | |
else if (buffer instanceof ArrayBuffer) { | |
this._buffer = Array.from(new Uint8Array(buffer)); | |
} | |
else if (buffer instanceof DataView || | |
buffer instanceof Writer || | |
buffer instanceof Uint8Array) { | |
this._buffer = Array.from(new Uint8Array(buffer.buffer)); | |
} | |
else { | |
throw new Error('Buffer type is neither Array, nor Uint8Array, nor ArrayBuffer, nor DataView, nor Writer'); | |
} | |
if (!offset || isNaN(offset)) | |
this.offset = 0; | |
else | |
this.offset = offset; | |
this.view = new DataView(new ArrayBuffer(8)); | |
this.littleEndian = littleEndian; | |
} | |
skip(offset = 1) { | |
this.offset += offset; | |
return this; | |
} | |
move(offset = 1) { | |
for (let i = 0; i < offset; i++) { | |
const byte = this.view.getUint8(i); | |
this._buffer[this.offset] = byte; | |
this.skip(); | |
} | |
return this; | |
} | |
writeUint8(val) { | |
this.view.setUint8(0, val); | |
this.move(); | |
return this; | |
} | |
writeInt8(val) { | |
this.view.setInt8(0, val); | |
this.move(); | |
return this; | |
} | |
writeUint16(val) { | |
this.view.setUint16(0, val, this.littleEndian); | |
this.move(2); | |
return this; | |
} | |
writeInt16(val) { | |
this.view.setInt16(0, val, this.littleEndian); | |
this.move(2); | |
return this; | |
} | |
writeUint32(val) { | |
this.view.setUint32(0, val, this.littleEndian); | |
this.move(4); | |
return this; | |
} | |
writeInt32(val) { | |
this.view.setInt32(0, val, this.littleEndian); | |
this.move(4); | |
return this; | |
} | |
writeBigUint64(val) { | |
this.view.setBigUint64(0, BigInt(val), this.littleEndian); | |
this.move(8); | |
return this; | |
} | |
writeBigInt64(val) { | |
this.view.setBigInt64(0, BigInt(val), this.littleEndian); | |
this.move(8); | |
return this; | |
} | |
writeFloat32(val) { | |
this.view.setFloat32(0, val, this.littleEndian); | |
this.move(4); | |
return this; | |
} | |
writeFloat64(val) { | |
this.view.setFloat64(0, val, this.littleEndian); | |
this.move(8); | |
return this; | |
} | |
writeString(val) { | |
for (let i = 0; i < val.length; i++) { | |
const charCode = val.charCodeAt(i); | |
this.writeUint16(charCode); | |
} | |
this.writeUint16(0); | |
} | |
get buffer() { | |
return new Uint8Array(this._buffer).buffer; | |
} | |
get byteLength() { | |
return this._buffer.length; | |
} | |
} | |
class BinaryReader { | |
constructor(data, offset = 0, littleEndian = true) { | |
this.offset = 0; | |
this.littleEndian = true; | |
if (data instanceof DataView || data instanceof BinaryWriter) { | |
this.buffer = data.buffer; | |
} | |
else if (data instanceof ArrayBuffer) { | |
this.buffer = data; | |
} | |
else { | |
throw new Error('Given data is neither DataView, nor ArrayBuffer, nor Writer'); | |
} | |
if (!offset || isNaN(offset)) | |
this.offset = 0; | |
else | |
this.offset = offset; | |
this.littleEndian = Boolean(littleEndian); | |
} | |
skip(offset = 1) { | |
this.offset += offset; | |
return this; | |
} | |
skipString() { | |
while (true) { | |
const char = this.readUint16(); | |
if (char === 0) | |
break; | |
} | |
return this; | |
} | |
readUint8() { | |
const result = this.view.getUint8(this.offset); | |
this.skip(); | |
return result; | |
} | |
readInt8() { | |
const result = this.view.getInt8(this.offset); | |
this.skip(); | |
return result; | |
} | |
readUint16() { | |
const result = this.view.getUint16(this.offset, this.littleEndian); | |
this.skip(2); | |
return result; | |
} | |
readInt16() { | |
const result = this.view.getInt16(this.offset, this.littleEndian); | |
this.skip(2); | |
return result; | |
} | |
readUint32() { | |
const result = this.view.getUint32(this.offset, this.littleEndian); | |
this.skip(4); | |
return result; | |
} | |
readInt32() { | |
const result = this.view.getInt32(this.offset, this.littleEndian); | |
this.skip(4); | |
return result; | |
} | |
readBigUint64() { | |
const result = this.view.getBigUint64(this.offset, this.littleEndian); | |
this.skip(8); | |
return result; | |
} | |
readBigInt64() { | |
const result = this.view.getBigInt64(this.offset, this.littleEndian); | |
this.skip(8); | |
return result; | |
} | |
readFloat32() { | |
const result = this.view.getFloat32(this.offset, this.littleEndian); | |
this.skip(4); | |
return result; | |
} | |
readFloat64() { | |
const result = this.view.getFloat64(this.offset, this.littleEndian); | |
this.skip(8); | |
return result; | |
} | |
readString() { | |
let result = ''; | |
while (true) { | |
const charCode = this.readUint16(); | |
if (charCode === 0) | |
break; | |
result += String.fromCharCode(charCode); | |
} | |
return result; | |
} | |
get buffer() { | |
return this.view.buffer; | |
} | |
set buffer(val) { | |
this.view = new DataView(val); | |
} | |
get byteLength() { | |
return this.view.byteLength; | |
} | |
} | |
window.BinaryReader = BinaryReader; | |
window.BinaryWriter = BinaryWriter; |
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