buffer-reader.ts•1.44 kB
const emptyBuffer = Buffer.allocUnsafe(0)
export class BufferReader {
private buffer: Buffer = emptyBuffer
// TODO(bmc): support non-utf8 encoding?
private encoding: string = 'utf-8'
constructor(private offset: number = 0) {}
public setBuffer(offset: number, buffer: Buffer): void {
this.offset = offset
this.buffer = buffer
}
public int16(): number {
const result = this.buffer.readInt16BE(this.offset)
this.offset += 2
return result
}
public byte(): number {
const result = this.buffer[this.offset]
this.offset++
return result
}
public int32(): number {
const result = this.buffer.readInt32BE(this.offset)
this.offset += 4
return result
}
public uint32(): number {
const result = this.buffer.readUInt32BE(this.offset)
this.offset += 4
return result
}
public string(length: number): string {
const result = this.buffer.toString(this.encoding, this.offset, this.offset + length)
this.offset += length
return result
}
public cstring(): string {
const start = this.offset
let end = start
// eslint-disable-next-line no-empty
while (this.buffer[end++] !== 0) {}
this.offset = end
return this.buffer.toString(this.encoding, start, end - 1)
}
public bytes(length: number): Buffer {
const result = this.buffer.slice(this.offset, this.offset + length)
this.offset += length
return result
}
}