Index: MythTV/MythDB.py
===================================================================
--- MythTV/MythDB.py	(revision 23116)
+++ MythTV/MythDB.py	(working copy)
@@ -5,10 +5,12 @@
 """
 import os
 import sys
-import xml.dom.minidom as minidom
+import xml.etree.cElementTree as etree
 import code
 import getopt
+import re
 from datetime import datetime
+from urllib import urlopen
 
 from MythLog import *
 
@@ -28,7 +30,7 @@
 	"""
 	A connection to the mythtv database.
 	"""
-	def __init__(self, args=None):
+	def __init__(self, args=None, **kwargs):
 		# Setup connection variables
 		dbconn = {
 				'host' : None,
@@ -47,7 +49,7 @@
 		found_config = False
 		for config_file in config_files:
 			try:
-				config = minidom.parse(config_file)
+				config = etree.parse(config_file).getroot()
 			except:
 				continue
 
@@ -55,22 +57,20 @@
 			dbconn['name'] = None
 			dbconn['user'] = None
 			dbconn['pass'] = None
-			for token in config.getElementsByTagName('Configuration')[0].getElementsByTagName('UPnP')[0].getElementsByTagName('MythFrontend')[0].getElementsByTagName('DefaultBackend')[0].childNodes:
-				if token.nodeType == token.TEXT_NODE:
-					continue
+			for child in config.find('UPnP').find('MythFrontend').find('DefaultBackend').getchildren():
 				try:
-					if token.tagName == "DBHostName":
-						dbconn['host'] = token.childNodes[0].data
-					elif token.tagName == "DBName":
-						dbconn['name'] = token.childNodes[0].data
-					elif token.tagName == "DBUserName":
-						dbconn['user'] = token.childNodes[0].data
-					elif token.tagName == "DBPassword":
-						dbconn['pass'] = token.childNodes[0].data
-					elif token.tagName == "USN":
-						dbconn['USN'] = token.childNodes[0].data
-					elif token.tagName == "SecurityPin":
-						dbconn['PIN'] = token.childNodes[0].data
+					if child.tag == "DBHostName":
+						dbconn['host'] = child.text
+					elif child.tag == "DBName":
+						dbconn['name'] = child.text
+					elif child.tag == "DBUserName":
+						dbconn['user'] = child.text
+					elif child.tag == "DBPassword":
+						dbconn['pass'] = child.text
+					elif child.tag == "USN":
+						dbconn['USN'] = child.text
+					elif child.tag == "SecurityPin":
+						dbconn['PIN'] = child.text
 				except:
 					pass
 
@@ -94,9 +94,19 @@
 		except:
 			pass
 
-		if not dbconn['host'] and not found_config:
-			raise MythError('Unable to find MythTV configuration file')
+		# Overrides from keyword parameters
+		for o, a in kwargs.items():
+			dbconn[o] = a
 
+		if not self._check_dbconn(dbconn):
+			# try to pull the information over upnp
+			if 'SecurityPin' not in dbconn:
+				dbconn['SecurityPin'] = 0
+			dbconn = self._listenUPNP(dhconn['SecurityPin'], 5.0)
+			if not self._check_dbconn(dbconn):
+				# no database credentials available
+				raise MythError('Unable to find MythTV configuration file')
+
 		try:
 			self.db = MySQLdb.connect(user=dbconn['user'], host=dbconn['host'],
 					passwd=dbconn['pass'], db=dbconn['name'], use_unicode=True,
@@ -114,6 +124,95 @@
 					sver, SCHEMA_VERSION)
 			raise MythError('Mismatched schema version')
 
+	def _check_dbconn(self, dbconn):
+		reqs = ['host','name','user','pass']
+		for req in reqs:
+			if req not in dbconn:
+				return False
+			if dbconn[req] is None:
+				return False
+		return True
+
+	def _listenUPNP(self, pin, timeout):
+		# open socket
+		upnpport = 1900
+		upnptup  = ('239.255.255.250', upnpport)
+		sreq = '\r\n'.join(['M-SEARCH * HTTP/1.1',
+							'HOST: %s:%s' % upnptup,
+							'MAN: "ssdp:discover"',
+							'MX: 5',
+							'ST: ssdp:all',''])
+
+		sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM,
+							socket.IPPROTO_UDP)
+		sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+		try:
+			sock.bind(('', upnpport))
+		except:
+			# socket already in use, exiting upnp attmept
+			return
+		sock.setblocking(0)
+
+		# spam the request a couple times
+		sock.sendto(sreq, upnptup)
+		sock.sendto(sreq, upnptup)
+		sock.sendto(sreq, upnptup)
+
+		reLOC = re.compile('http://(?P<ip>[0-9\.]+):(?P<port>[0-9]+)/.*')
+		# listen for <timeout>
+		atime = time()+timeout
+		while time() < atime:
+			sleep(0.1)
+			try:
+				sdata, saddr = sock.recvfrom(2048)
+			except socket.error:
+				continue # on fault from nonblocking recv
+
+			lines = sdata.split('\n')
+			sdict = {'request':lines[0].strip()}
+			for line in lines[1:]:
+				fields = line.split(':',1)
+				if len(fields) == 2:
+					sdict[fields[0].strip().lower()] = fields[1].strip()
+
+			if 'st' not in sdict:
+				continue
+			if sdict['st'] not in \
+						('urn:schemas-mythtv-org:device:MasterMediaServer:1',
+						'urn:schemas-mythtv-org:device:SlaveMediaServer:1',
+						'urn:schemas-upnp-org:device:MediaServer:1'):
+				continue
+			ip, port = reLOC.match(sdict['location']).group(1,2)
+			try:
+				dbconn = self._processPage(ip, port, pin)
+				break
+			except:
+				continue
+
+		else:
+			sock.close()
+			return {}
+
+		sock.close()
+		return dbconn
+
+	def _processPage(self, ip, port, pin):
+		dbconn = {'SecurityPin':pin}
+		# try opening settings page with SecurityPin
+		up = urlopen('http://%s:%s/Myth/GetConnectionInfo?Pin=%s' \
+										% (ip, port, pin))
+		config = etree.fromstring(up.read())
+		up.close()
+
+		# load data from webpage
+		conv = {'Host':'host', 'UserName':'user', 'Password':'pass', 'Name':'name'}
+		for child in config.find('Info').find('Database').getchildren():
+			if child.tag in conv:
+				dbconn[conv[child.tag]] = child.text
+		if not self._check_dbconn(dbconn):
+			return {}
+		return dbconn
+
 	def __del__(self):
 		self.db.close()