54 lines
1.2 KiB
TypeScript
54 lines
1.2 KiB
TypeScript
const emptyBuffer = Buffer.allocUnsafe(0)
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export class BufferReader {
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private buffer: Buffer = emptyBuffer
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// TODO(bmc): support non-utf8 encoding?
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private encoding: string = 'utf-8'
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constructor(private offset: number = 0) {}
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public setBuffer(offset: number, buffer: Buffer): void {
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this.offset = offset
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this.buffer = buffer
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}
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public int16(): number {
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const result = this.buffer.readInt16BE(this.offset)
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this.offset += 2
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return result
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}
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public byte(): number {
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const result = this.buffer[this.offset]
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this.offset++
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return result
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}
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public int32(): number {
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const result = this.buffer.readInt32BE(this.offset)
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this.offset += 4
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return result
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}
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public string(length: number): string {
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const result = this.buffer.toString(this.encoding, this.offset, this.offset + length)
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this.offset += length
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return result
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}
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public cstring(): string {
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const start = this.offset
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let end = start
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while (this.buffer[end++] !== 0) {}
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this.offset = end
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return this.buffer.toString(this.encoding, start, end - 1)
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}
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public bytes(length: number): Buffer {
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const result = this.buffer.slice(this.offset, this.offset + length)
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this.offset += length
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return result
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}
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}
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