initial commit

protocols/core.js

@@ -0,0 +1,136 @@
+var EventEmitter = require('events').EventEmitter,
+	dns = require('dns'),
+	async = require('async'),
+	Class = require('../Class'),
+	Bignum = require('bignum'),
+	Reader = require('../reader');
+
+module.exports = Class.extend(EventEmitter,{
+	init: function() {
+		this._super();
+		this.options = {};
+		this.maxAttempts = 1;
+		this.attempt = 1;
+		this.finished = false;
+		this.encoding = 'utf8';
+		this.byteorder = 'le';
+		this.delimiter = '\0';
+
+		var self = this;
+		this.globalTimeoutTimer = setTimeout(function() {
+			self.fatal('timeout');
+		},10000);
+	},
+
+	fatal: function(err) {
+		this.error(err,true);
+	},
+	error: function(err,fatal) {
+		if(!fatal && this.attempt < this.maxAttempts) {
+			this.attempt++;
+			this.start();
+			return;
+		}
+
+		this.done({error: err.toString()});
+	},
+	finish: function(result) {
+		this.done(result);
+	},
+	done: function(result) {
+		if(this.finished) return;
+
+		clearTimeout(this.globalTimeoutTimer);
+
+		if(this.options.notes)
+			result.notes = this.options.notes;
+
+		this.reset();
+		this.finished = true;
+		this.emit('finished',result);
+	},
+
+	reset: function() {
+		if(this.timers) {
+			this.timers.forEach(function(timer) {
+				clearTimeout(timer);
+			});
+		}
+		this.timers = [];
+
+		this.udpTimeoutTimer = false;
+		this.udpCallback = false;
+	},
+	start: function() {
+		var self = this;
+		this.reset();
+
+		async.series([
+			function(c) {
+				// resolve host names
+				if(!('host' in self.options)) return c();
+				if(self.options.host.match(/\d+\.\d+\.\d+\.\d+/)) {
+					self.options.address = self.options.host;
+					c();
+				} else {
+					dns.lookup(self.options.host, function(err,address,family) {
+						if(err) return self.error(err);
+						self.options.address = address;
+						c();
+					});
+				}
+			}, function(c) {
+				self.run();
+			}
+
+		]);
+	},
+
+	reader: function(buffer) {
+		return new Reader(this,buffer);
+	},
+
+	setTimeout: function(c,t) {
+		if(this.finished) return 0;
+		var id = setTimeout(c,t);
+		this.timers.push(id);
+		return id;
+	},
+
+	udpSend: function(buffer,onpacket,ontimeout) {
+		var self = this;
+		process.nextTick(function() {
+			if(self.udpCallback) return self.fatal('Attempted to send UDP packet while still waiting on a managed response');
+			self._udpSendNow(buffer);
+			if(!onpacket) return;
+
+			self.udpTimeoutTimer = self.setTimeout(function() {
+				self.udpCallback = false;
+				var timeout = false;
+				if(!ontimeout || ontimeout() !== true) timeout = true;
+				if(timeout) self.error('timeout');
+			},1000);
+			self.udpCallback = onpacket;
+		});
+	},
+	_udpSendNow: function(buffer) {
+		if(!('port' in this.options)) return this.fatal('Attempted to send without setting a port');
+		if(!('address' in this.options)) return this.fatal('Attempted to send without setting an address');
+
+		if(typeof buffer == 'string') buffer = new Buffer(buffer,'binary');
+		this.udpSocket.send(buffer,0,buffer.length,this.options.port,this.options.address);
+	},
+	_udpResponse: function(buffer) {
+		if(this.udpCallback) {
+			var result = this.udpCallback(buffer);
+			if(result === true) {
+				// we're done with this udp session
+				clearTimeout(this.udpTimeoutTimer);
+				this.udpCallback = false;
+			}
+		} else {
+			this.udpResponse(buffer);
+		}
+	},
+	udpResponse: function() {}
+});