buffer = new Buffer(1024 * 1024);
buffer_size = 0;
 
client = new net.Socket();
client.on('data', function(data){
	data.copy(buffer, buffer_size, 0, data.length);
	buffer_size += data.length;
	while (packet = getPacket()){
		//process packet
	}
});
 
function getPacket(){
	if (buffer_size >= 4 && buffer_size >= buffer.readUint32LE(0)){
		const packet_size = buffer.readUint32LE(0);
		const packet = new Buffer(packet_size);
		buffer.copy(packet, 0, 0, packet_size);
		buffer.copy(buffer, 0, packet_size, buffer_size); // cut off a full packet
		buffer_size -= packet_size;
		return packet;
	}
}

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