Discover a B2G simulator port in NodeJS

b2g_discovery.js

var discoverPorts = function (callback) {
	
	var ports = [];

	if (os == 'darwin') {
		var output = exec(LSOF_CMD, {silent: true}).output;
		var regex = /^b2g[-bin]?.*[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+:([0-9]*)/;
		var lines = output.split('\n');
		for (var line=0; line < lines.length; line++) {
			var matches = regex.exec(lines[line]);
			
			if (matches && +matches[1] != 2828)
				ports.push(+matches[1])
		}

	} else
	if (os == 'linux') {
		var output = exec(NETSTAT_CMD, {silent: true}).output;
		var regex = /tcp.*[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+:([0-9]+).*LISTEN.*\/b2g[-bin]?/
		var lines = output.split('\n');
		for (var line=0; line < lines.length; line++) {
			var matches = regex.exec(lines[line]);
			
			if (matches && +matches[1] != 2828)
				ports.push(+matches[1])
		}

	} else {
		return callback(new Error("OS not supported for running"))
	}

	callback(null, ports)

}