knxultimate/src/protocol/cEMI/TLVInfo.ts

KNX IP protocol implementation for Node. This is the ENGINE of Node-Red KNX-Ultimate node.

/**
 * Parses TLV info blocks in KNX cEMI frames.
 *
 * Written in Italy with love, sun and passion, by Massimo Saccani.
 *
 * Released under the MIT License.
 * Use at your own risk; the author assumes no liability for damages.
 */

export default class TLVInfo {
	type: number

	length: number

	info: Buffer

	constructor(type: number, length: number, info: Buffer) {
		this.type = type
		this.length = length
		this.info = info
	}

	static createFromBuffer(buffer: Buffer, offset: number = 0): TLVInfo {
		const type: number = buffer.readUInt8(offset++)
		const length: number = buffer.readUInt8(offset++)
		const info: Buffer = Buffer.alloc(length)
		for (let i: number = 0; i < length; i++) {
			info.writeUInt8(buffer.readUInt8(offset++), i)
		}
		return new TLVInfo(type, length, info)
	}

	toBuffer(): Buffer {
		const buffer: Buffer = Buffer.alloc(2)
		buffer.writeUInt8(this.type, 0)
		buffer.writeUInt8(this.length, 1)
		return Buffer.concat([buffer, this.info])
	}
}