sbsv2/raptor/python/raptor_xml.py
changeset 13 c327db0664bb
parent 2 39c28ec933dd
child 18 de5b887c98f7
--- a/sbsv2/raptor/python/raptor_xml.py	Sun May 16 13:06:27 2010 +0100
+++ b/sbsv2/raptor/python/raptor_xml.py	Mon May 17 20:20:32 2010 +0100
@@ -1,363 +1,399 @@
-#
-# Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
-# All rights reserved.
-# This component and the accompanying materials are made available
-# under the terms of the License "Eclipse Public License v1.0"
-# which accompanies this distribution, and is available
-# at the URL "http://www.eclipse.org/legal/epl-v10.html".
-#
-# Initial Contributors:
-# Nokia Corporation - initial contribution.
-#
-# Contributors:
-#
-# Description: 
-# raptor_xml module
-#
-
-import os
-import raptor_data
-import raptor_utilities
-import xml.dom.minidom
-import re
-import generic_path
-
-# raptor_xml module attributes
-
-namespace = "http://symbian.com/xml/build"
-xsdVersion = "build/2_0.xsd"
-xsdIgnore = "build/666.xsd"
-
-_constructors = {"alias":raptor_data.Alias,
-				 "aliasRef":raptor_data.AliasRef,
-				 "append":raptor_data.Append,
-				 "env":raptor_data.Env,
-				 "group":raptor_data.Group,
-				 "groupRef":raptor_data.GroupRef,
-				 "interface":raptor_data.Interface,
-				 "interfaceRef":raptor_data.InterfaceRef,
-				 "param":raptor_data.Parameter,
-				 "paramgroup":raptor_data.ParameterGroup,
-				 "prepend":raptor_data.Prepend,
-				 "set":raptor_data.Set,
-				 "spec":raptor_data.Specification,
-				 "var":raptor_data.Variant,
-				 "varRef":raptor_data.VariantRef}
-
-
-# raptor_xml module classes
-
-class XMLError(Exception):
-	pass
-
-# raptor_xml module functions
-
-def Read(Raptor, filename):
-	"Read in a Raptor XML document"
-
-	# try to read and parse the XML file
-	try:
-		dom = xml.dom.minidom.parse(filename)
-
-	except: # a whole bag of exceptions can be raised here
-		raise XMLError
-
-	# <build> is always the root element
-	build = dom.documentElement
-	objects = []
-
-	fileVersion = build.getAttribute("xsi:schemaLocation")
-	
-	# ignore the file it matches the "invalid" schema
-	if fileVersion.endswith(xsdIgnore):
-		return objects
-		
-	# check that the file matches the expected schema
-	if not fileVersion.endswith(xsdVersion):
-		Raptor.Warn("file '%s' uses schema '%s' which does not end with the expected version '%s'", filename, fileVersion, xsdVersion)
-		
-	# create a Data Model object from each sub-element
-	for child in build.childNodes:
-		if child.namespaceURI == namespace \
-		and child.nodeType == child.ELEMENT_NODE:
-			try:
-				o = XMLtoDataModel(Raptor, child)
-				if o is not None:
-					objects.append(o)
-			except raptor_data.InvalidChildError:
-				Raptor.Warn("Invalid element %s in %s", child.localName, filename)
-
-	# discard the XML
-	dom.unlink()
-	return objects
-
-
-def XMLtoDataModel(Raptor, node):
-	"Create a data-model object from an XML element"
-
-	# look-up a function to create an object from the node name
-	try:
-		constructor = _constructors[node.localName]
-
-	except KeyError:
-		Raptor.Warn("Unknown element %s", node.localName)
-		return
-
-	model = constructor()
-
-	# deal with the attributes first
-	if node.hasAttributes():
-		for i in range(node.attributes.length):
-			attribute = node.attributes.item(i)
-			try:
-
-				model.SetProperty(attribute.localName, attribute.value)
-
-			except raptor_data.InvalidPropertyError:
-				Raptor.Warn("Can't set attribute %s for element %s",
-							 attribute.localName, node.localName)
-
-	# add the sub-elements
-	for child in node.childNodes:
-		if child.namespaceURI == namespace \
-		and child.nodeType == child.ELEMENT_NODE:
-			try:
-				gc = XMLtoDataModel(Raptor, child)
-				if gc is not None:
-					model.AddChild(gc)
-
-			except raptor_data.InvalidChildError:
-				Raptor.Warn("Can't add child %s to element %s",
-							 child.localName, node.localName)
-
-	# only return a valid object (or raise error)
-	if model.Valid():
-		if model.IsApplicable():
-			return model
-		else:
-			return None
-	else:
-		raise raptor_data.InvalidChildError
-
-
-class SystemModelComponent(generic_path.Path):
-	"""Path sub-class that wraps up a component bld.inf file with
-	system_definition.xml context information."""
-
-	def __init__(self, aBldInfFile, aContainerNames, aSystemDefinitionFile, aSystemDefinitionBase, aSystemDefinitionVersion):
-		generic_path.Path.__init__(self, aBldInfFile.Absolute().path)
-		self.__ContainerNames = aContainerNames
-		self.__SystemDefinitionFile = aSystemDefinitionFile
+#
+# Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies).
+# All rights reserved.
+# This component and the accompanying materials are made available
+# under the terms of the License "Eclipse Public License v1.0"
+# which accompanies this distribution, and is available
+# at the URL "http://www.eclipse.org/legal/epl-v10.html".
+#
+# Initial Contributors:
+# Nokia Corporation - initial contribution.
+#
+# Contributors:
+#
+# Description: 
+# raptor_xml module
+#
+
+import os
+import raptor_data
+import raptor_utilities
+import xml.dom.minidom
+import re
+import generic_path
+
+# raptor_xml module attributes
+
+namespace = "http://symbian.com/xml/build"
+xsdVersion = "build/2_0.xsd"
+xsdIgnore = "build/666.xsd"
+
+_constructors = {"alias":raptor_data.Alias,
+				 "aliasRef":raptor_data.AliasRef,
+				 "append":raptor_data.Append,
+				 "env":raptor_data.Env,
+				 "group":raptor_data.Group,
+				 "groupRef":raptor_data.GroupRef,
+				 "interface":raptor_data.Interface,
+				 "interfaceRef":raptor_data.InterfaceRef,
+				 "param":raptor_data.Parameter,
+				 "paramgroup":raptor_data.ParameterGroup,
+				 "prepend":raptor_data.Prepend,
+				 "set":raptor_data.Set,
+				 "spec":raptor_data.Specification,
+				 "var":raptor_data.Variant,
+				 "varRef":raptor_data.VariantRef}
+
+
+# raptor_xml module classes
+
+class XMLError(Exception):
+	pass
+
+# raptor_xml module functions
+
+def Read(Raptor, filename):
+	"Read in a Raptor XML document"
+
+	# try to read and parse the XML file
+	try:
+		dom = xml.dom.minidom.parse(filename)
+
+	except: # a whole bag of exceptions can be raised here
+		raise XMLError
+
+	# <build> is always the root element
+	build = dom.documentElement
+	objects = []
+
+	fileVersion = build.getAttribute("xsi:schemaLocation")
+	
+	# ignore the file it matches the "invalid" schema
+	if fileVersion.endswith(xsdIgnore):
+		return objects
+		
+	# check that the file matches the expected schema
+	if not fileVersion.endswith(xsdVersion):
+		Raptor.Warn("file '%s' uses schema '%s' which does not end with the expected version '%s'", filename, fileVersion, xsdVersion)
+		
+	# create a Data Model object from each sub-element
+	for child in build.childNodes:
+		if child.namespaceURI == namespace \
+		and child.nodeType == child.ELEMENT_NODE:
+			try:
+				o = XMLtoDataModel(Raptor, child)
+				if o is not None:
+					objects.append(o)
+			except raptor_data.InvalidChildError:
+				Raptor.Warn("Invalid element %s in %s", child.localName, filename)
+
+	# discard the XML
+	dom.unlink()
+	return objects
+
+
+def XMLtoDataModel(Raptor, node):
+	"Create a data-model object from an XML element"
+
+	# look-up a function to create an object from the node name
+	try:
+		constructor = _constructors[node.localName]
+
+	except KeyError:
+		Raptor.Warn("Unknown element %s", node.localName)
+		return
+
+	model = constructor()
+
+	# deal with the attributes first
+	if node.hasAttributes():
+		for i in range(node.attributes.length):
+			attribute = node.attributes.item(i)
+			try:
+
+				model.SetProperty(attribute.localName, attribute.value)
+
+			except raptor_data.InvalidPropertyError:
+				Raptor.Warn("Can't set attribute %s for element %s",
+							 attribute.localName, node.localName)
+
+	# add the sub-elements
+	for child in node.childNodes:
+		if child.namespaceURI == namespace \
+		and child.nodeType == child.ELEMENT_NODE:
+			try:
+				gc = XMLtoDataModel(Raptor, child)
+				if gc is not None:
+					model.AddChild(gc)
+
+			except raptor_data.InvalidChildError:
+				Raptor.Warn("Can't add child %s to element %s",
+							 child.localName, node.localName)
+
+	# only return a valid object (or raise error)
+	if model.Valid():
+		if model.IsApplicable():
+			return model
+		else:
+			return None
+	else:
+		raise raptor_data.InvalidChildError
+
+
+class SystemModelComponent(generic_path.Path):
+	"""Path sub-class that wraps up a component bld.inf file with
+	system_definition.xml context information."""
+
+	def __init__(self, aBldInfFile, aLayerName, aContainerNames, aSystemDefinitionFile, aSystemDefinitionBase, aSystemDefinitionVersion):
+		generic_path.Path.__init__(self, aBldInfFile.Absolute().path)
+		self.__ContainerNames = aContainerNames
+		self.__LayerName = aLayerName
+		self.__SystemDefinitionFile = aSystemDefinitionFile
 		self.__SystemDefinitionBase = aSystemDefinitionBase
 		self.__SystemDefinitionVersion = aSystemDefinitionVersion
-
-	def GetSystemDefinitionFile(self):
-		return self.__SystemDefinitionFile
+
+	def GetSystemDefinitionFile(self):
+		return self.__SystemDefinitionFile
+
+	def GetSystemDefinitionBase(self):
+		return self.__SystemDefinitionBase
 
-	def GetSystemDefinitionBase(self):
-		return self.__SystemDefinitionBase
-
-	def GetSystemDefinitionFile(self):
+	def GetSystemDefinitionVersion(self):
 		return self.__SystemDefinitionVersion
 
-	def GetContainerName(self, aContainerType):
-		if self.__ContainerNames.has_key(aContainerType):
-		  return self.__ContainerNames[aContainerType]
-		return ""
-
-
-class SystemModel(object):
-	"""A representation of the SystemModel section of a Symbian system_definition.xml file."""
-
-	def __init__(self, aLogger, aSystemDefinitionFile, aSystemDefinitionBase):
-		self.__Logger = aLogger
-		self.__SystemDefinitionFile = aSystemDefinitionFile.GetLocalString()
-		self.__SystemDefinitionBase = aSystemDefinitionBase.GetLocalString()
+	def GetLayerName(self):
+		return self.__LayerName
+
+	def GetContainerName(self, aContainerType):
+		if self.__ContainerNames.has_key(aContainerType):
+			return self.__ContainerNames[aContainerType]
+		return ""
+
+
+class SystemModel(object):
+	"""A representation of the SystemModel section of a Symbian system_definition.xml file."""
+
+	def __init__(self, aLogger, aSystemDefinitionFile, aSystemDefinitionBase):
+		self.__Logger = aLogger
+		self.__SystemDefinitionFile = aSystemDefinitionFile.GetLocalString()
+		self.__SystemDefinitionBase = aSystemDefinitionBase.GetLocalString()
 		self.__Version = {'MAJOR':0,'MID':0,'MINOR':0}
-		self.__ComponentRoot = ""
-		self.__TotalComponents = 0
-		self.__LayerList = []
-		self.__LayerDetails = {}
-
-		self.__DOM = None
-		self.__SystemDefinitionElement = None
-
-		if self.__Read():
-			if self.__Validate():
-				self.__Parse()
-
-		if self.__DOM:
-			self.__DOM.unlink()
-
-	def HasLayer(self, aLayer):
-		return aLayer in self.__LayerList
-
-	def GetLayerNames(self):
-		return self.__LayerList
-
-	def GetLayerComponents(self, aLayer):
-		if not self.HasLayer(aLayer):
-			self.__Logger.Error("System Definition layer \"%s\" does not exist in %s", aLayer, self.__SystemDefinitionFile)
-			return []
-
-		return self.__LayerDetails[aLayer]
-
-	def IsLayerBuildable(self, aLayer):
-		if len(self.GetLayerComponents(aLayer)):
-			return True
-		return False
-
-	def GetAllComponents(self):
-		components = []
-
-		for layer in self.GetLayerNames():
-			components.extend(self.GetLayerComponents(layer))
-
-		return components
-
-	def DumpLayerInfo(self, aLayer):
-		if self.HasLayer(aLayer):
-			self.__Logger.Info("Found %d bld.inf references in layer \"%s\"", len(self.GetLayerComponents(aLayer)), aLayer)
-
-	def DumpInfo(self):
-		self.__Logger.Info("Found %d bld.inf references in %s within %d layers:", len(self.GetAllComponents()), self.__SystemDefinitionFile, len(self.GetLayerNames()))
-		self.__Logger.Info("\t%s", ", ".join(self.GetLayerNames()))
-
-	def __Read(self):
-		if not os.path.exists(self.__SystemDefinitionFile):
-			self.__Logger.Error("System Definition file %s does not exist", self.__SystemDefinitionFile)
-			return False
-
-		self.__Logger.Info("System Definition file %s", self.__SystemDefinitionFile)
-
-		# try to read the XML file
-		try:
-			self.__DOM = xml.dom.minidom.parse(self.__SystemDefinitionFile)
-
-		except: # a whole bag of exceptions can be raised here
-			self.__Logger.Error("Failed to parse XML file %s", self.__SystemDefinitionFile)
-			return False
-
-		# <SystemDefinition> is always the root element
-		self.__SystemDefinitionElement = self.__DOM.documentElement
-
-		return True
-
-	def __Validate(self):
-		# account for different schema versions in processing
-		# old format : version >= 1.3.0
-		# new format : version >= 2.0.0 (assume later versions are compatible...at least for now)
-		version = re.match(r'(?P<MAJOR>\d)\.(?P<MID>\d)(\.(?P<MINOR>\d))?', self.__SystemDefinitionElement.getAttribute("schema"))
-
-		if not version:
-			self.__Logger.Error("Cannot determine schema version of XML file %s", self.__SystemDefinitionFile)
-			return False
-
-		self.__Version['MAJOR'] = int(version.group('MAJOR'))
-		self.__Version['MID'] = int(version.group('MID'))
-		self.__Version['MINOR'] = int(version.group('MINOR'))
-
-		if self.__Version['MAJOR'] == 1 and self.__Version['MID'] > 2:
-			self.__ComponentRoot = self.__SystemDefinitionBase
-		elif self.__Version['MAJOR'] == 2:
-			# 2.0.0 format supports SOURCEROOT as an environment specified base - we respect this, unless
+		self.__IdAttribute = "name"
+		self.__ComponentRoot = ""
+		self.__TotalComponents = 0
+		self.__LayerList = []
+		self.__LayerDetails = {}
+
+		self.__DOM = None
+		self.__SystemDefinitionElement = None
+
+		if self.__Read():
+			if self.__Validate():
+				self.__Parse()
+
+		if self.__DOM:
+			self.__DOM.unlink()
+
+	def HasLayer(self, aLayer):
+		return aLayer in self.__LayerList
+
+	def GetLayerNames(self):
+		return self.__LayerList
+
+	def GetLayerComponents(self, aLayer):
+		if not self.HasLayer(aLayer):
+			self.__Logger.Error("System Definition layer \"%s\" does not exist in %s", aLayer, self.__SystemDefinitionFile)
+			return []
+
+		return self.__LayerDetails[aLayer]
+
+	def IsLayerBuildable(self, aLayer):
+		if len(self.GetLayerComponents(aLayer)):
+			return True
+		return False
+
+	def GetAllComponents(self):
+		components = []
+
+		for layer in self.GetLayerNames():
+			components.extend(self.GetLayerComponents(layer))
+
+		return components
+
+	def DumpLayerInfo(self, aLayer):
+		if self.HasLayer(aLayer):
+			self.__Logger.Info("Found %d bld.inf references in layer \"%s\"", len(self.GetLayerComponents(aLayer)), aLayer)
+
+	def DumpInfo(self):
+		self.__Logger.Info("Found %d bld.inf references in %s within %d layers:", len(self.GetAllComponents()), self.__SystemDefinitionFile, len(self.GetLayerNames()))
+		self.__Logger.Info("\t%s", ", ".join(self.GetLayerNames()))
+		self.__Logger.InfoDiscovery(object_type = "layers",
+				count = len(self.GetLayerNames()))
+		self.__Logger.InfoDiscovery(object_type = "bld.inf references",
+				count = len(self.GetAllComponents()))
+
+	def __Read(self):
+		if not os.path.exists(self.__SystemDefinitionFile):
+			self.__Logger.Error("System Definition file %s does not exist", self.__SystemDefinitionFile)
+			return False
+
+		self.__Logger.Info("System Definition file %s", self.__SystemDefinitionFile)
+
+		# try to read the XML file
+		try:
+			self.__DOM = xml.dom.minidom.parse(self.__SystemDefinitionFile)
+
+		except: # a whole bag of exceptions can be raised here
+			self.__Logger.Error("Failed to parse XML file %s", self.__SystemDefinitionFile)
+			return False
+
+		# <SystemDefinition> is always the root element
+		self.__SystemDefinitionElement = self.__DOM.documentElement
+
+		return True
+
+	def __Validate(self):
+		# account for different schema versions in processing
+		# old format : version >= 1.3.0
+		# new format : version >= 2.0.0 (assume later versions are compatible...at least for now)
+		version = re.match(r'(?P<MAJOR>\d)\.(?P<MID>\d)(\.(?P<MINOR>\d))?', self.__SystemDefinitionElement.getAttribute("schema"))
+
+		if not version:
+			self.__Logger.Error("Cannot determine schema version of XML file %s", self.__SystemDefinitionFile)
+			return False
+
+		self.__Version['MAJOR'] = int(version.group('MAJOR'))
+		self.__Version['MID'] = int(version.group('MID'))
+		self.__Version['MINOR'] = int(version.group('MINOR'))
+
+		if self.__Version['MAJOR'] == 1 and self.__Version['MID'] > 2:
+			self.__ComponentRoot = self.__SystemDefinitionBase
+		elif self.__Version['MAJOR'] == 2 or self.__Version['MAJOR'] == 3:
+			# 2.0.x and 3.0.0 formats support SOURCEROOT or SRCROOT as an environment specified base - we respect this, unless
 			# explicitly overridden on the command line
-			if os.environ.has_key('SOURCEROOT'):
-				self.__ComponentRoot = generic_path.Path(os.environ['SOURCEROOT'])
+			if os.environ.has_key('SRCROOT'):
+				self.__ComponentRoot = generic_path.Path(os.environ['SRCROOT'])
+			elif os.environ.has_key('SOURCEROOT'):
+				self.__ComponentRoot = generic_path.Path(os.environ['SOURCEROOT'])
+				
 			if self.__SystemDefinitionBase and self.__SystemDefinitionBase != ".":
 				self.__ComponentRoot = self.__SystemDefinitionBase
-				if os.environ.has_key('SOURCEROOT'):
+				if os.environ.has_key('SRCROOT'):
+					self.__Logger.Info("Command line specified System Definition file base \'%s\' overriding environment SRCROOT \'%s\'", self.__SystemDefinitionBase, os.environ['SRCROOT'])
+				elif os.environ.has_key('SOURCEROOT'):
 					self.__Logger.Info("Command line specified System Definition file base \'%s\' overriding environment SOURCEROOT \'%s\'", self.__SystemDefinitionBase, os.environ['SOURCEROOT'])
-		else:
-			self.__Logger.Error("Cannot process schema version %s of file %s", version.string, self.__SystemDefinitionFile)
-			return False
-
-		return True
-
-	def __Parse(self):
-		# find the <systemModel> element (there can be 0 or 1) and search any <layer> elements for <unit> elements with "bldFile" attributes
-		# the <layer> context of captured "bldFile" attributes is recorded as we go
-		for child in self.__SystemDefinitionElement.childNodes:
-			if child.localName == "systemModel":
-				self.__ProcessSystemModelElement(child)
-
-	def __CreateComponent(self, aBldInfFile, aUnitElement):
-		# take a resolved bld.inf file and associated <unit/> element and returns a populated Component object
-		containers = {}
-		self.__GetElementContainers(aUnitElement, containers)
-		component = SystemModelComponent(aBldInfFile, containers, self.__SystemDefinitionFile, self.__SystemDefinitionBase, self.__Version)
-
-		return component
+		else:
+			self.__Logger.Error("Cannot process schema version %s of file %s", version.string, self.__SystemDefinitionFile)
+			return False
 
-	def __GetElementContainers(self, aElement, aContainers):
-		# take a <unit/> element and creates a type->name dictionary of all of its parent containers
-		# We're only interested in parent nodes if they're not the top-most node
-		if aElement.parentNode.parentNode:
-			parent = aElement.parentNode
-			name = parent.getAttribute("name")
-
-			if name:
-				aContainers[parent.tagName] = name
-
-			self.__GetElementContainers(parent, aContainers)
+		if self.__Version['MAJOR'] >= 3:
+			# id is the unique identifier for 3.0 and later schema
+			self.__IdAttribute = "id"
+
+		return True
+
+	def __Parse(self):
+		# For 2.0 and earlier: find the <systemModel> element (there can be 0 or 1) and search any <layer> elements for <unit> elements with "bldFile" attributes
+		# the <layer> context of captured "bldFile" attributes is recorded as we go
+		# For 3.0 and later, process any architectural topmost element, use the topmost element with an id as the "layer"
+		for child in self.__SystemDefinitionElement.childNodes:
+			if child.localName in ["systemModel", "layer", "package", "collection", "component"]:
+				self.__ProcessSystemModelElement(child)
+
+	def __CreateComponent(self, aBldInfFile, aUnitElement):
+		# take a resolved bld.inf file and associated <unit/> element and returns a populated Component object
+		containers = {}
+		self.__GetElementContainers(aUnitElement, containers)
+		layer = self.__GetEffectiveLayer(aUnitElement)
+		component = SystemModelComponent(aBldInfFile, layer, containers, self.__SystemDefinitionFile, self.__SystemDefinitionBase, self.__Version)
+
+		return component
 
-	def __ProcessSystemModelElement(self, aElement):
-		"""Search for XML <unit/> elements with 'bldFile' attributes and resolve concrete bld.inf locations
-		with an appreciation of different schema versions."""
-
-		if aElement.tagName == "layer":
-			currentLayer = aElement.getAttribute("name")
-
-			if not self.__LayerDetails.has_key(currentLayer):
-				self.__LayerDetails[currentLayer] = []
-
-			if not currentLayer in self.__LayerList:
-				self.__LayerList.append(currentLayer)
+	def __GetEffectiveLayer(self, aElement):
+		#' return the ID of the topmost item which has an ID. For 1.x and 2.x, this will always be layer, for 3.x, it will be the topmost ID'd element in the file
+		# never call this on the root element
+		if aElement.parentNode.hasAttribute(self.__IdAttribute):
+			return self.__GetEffectiveLayer(aElement.parentNode)
+		elif aElement.hasAttribute(self.__IdAttribute):
+			return aElement.getAttribute(self.__IdAttribute)
+		return ""
+
+	def __GetElementContainers(self, aElement, aContainers):
+		# take a <unit/> element and creates a type->name dictionary of all of its parent containers
+		# We're only interested in parent nodes if they're not the top-most node
+		if aElement.parentNode.parentNode:
+			parent = aElement.parentNode
+			name = parent.getAttribute(self.__IdAttribute)
+
+			if name:
+				aContainers[parent.tagName] = name
+
+			self.__GetElementContainers(parent, aContainers)
+
+	def __ProcessSystemModelElement(self, aElement):
+		"""Search for XML <unit/> elements with 'bldFile' attributes and resolve concrete bld.inf locations
+		with an appreciation of different schema versions."""
 
-		elif aElement.tagName == "unit" and aElement.hasAttributes():
-			bldFileValue = aElement.getAttribute("bldFile")
-
-			if bldFileValue:
-				bldInfRoot = self.__ComponentRoot
-
-				if self.__Version['MAJOR'] == 1 and self.__Version['MID'] == 4:
-					# version 1.4.x schema paths can use DOS slashes
-					bldFileValue = raptor_utilities.convertToUnixSlash(bldFileValue)
-				elif self.__Version['MAJOR'] == 2:
-					# version 2.x.x schema paths are subject to a "root" attribute off-set, if it exists
-					rootValue = aElement.getAttribute("root")
-
-					if rootValue:
-						if os.environ.has_key(rootValue):
-							bldInfRoot = generic_path.Path(os.environ[rootValue])
-						else:
-							# Assume that this is an error i.e. don't attempt to resolve in relation to SOURCEROOT
-							bldInfRoot = None
-							self.__Logger.Error("Cannot resolve \'root\' attribute value \"%s\" in %s", rootValue, self.__SystemDefinitionFile)
-							return
-
-				group = generic_path.Path(bldFileValue)
-
-				if not group.isAbsolute() and bldInfRoot:
-					group = generic_path.Join(bldInfRoot, group)
-
-				bldinf = generic_path.Join(group, "bld.inf").FindCaseless()
-
-				if bldinf == None:
-					self.__Logger.Error("No bld.inf found at %s in %s", group.GetLocalString(), self.__SystemDefinitionFile)
+		# The effective "layer" is the item whose parent does not have an id (or name in 2.x and earlier)
+		if not aElement.parentNode.hasAttribute(self.__IdAttribute) :
+			currentLayer = aElement.getAttribute(self.__IdAttribute)
+
+			if not self.__LayerDetails.has_key(currentLayer):
+				self.__LayerDetails[currentLayer] = []
+
+			if not currentLayer in self.__LayerList:
+				self.__LayerList.append(currentLayer)
+
+		elif aElement.tagName == "unit" and aElement.hasAttributes():
+			bldFileValue = aElement.getAttribute("bldFile")
+
+			if bldFileValue:
+				bldInfRoot = self.__ComponentRoot
+
+				if self.__Version['MAJOR'] == 1:
+					# version 1.x schema paths can use DOS slashes
+					bldFileValue = raptor_utilities.convertToUnixSlash(bldFileValue)
+				elif self.__Version['MAJOR'] >= 2:
+					# version 2.x.x schema paths are subject to a "root" attribute off-set, if it exists
+					rootValue = aElement.getAttribute("root")
+
+					if rootValue:
+						if os.environ.has_key(rootValue):
+							bldInfRoot = generic_path.Path(os.environ[rootValue])
+						else:
+							# Assume that this is an error i.e. don't attempt to resolve in relation to SOURCEROOT
+							bldInfRoot = None
+							self.__Logger.Error("Cannot resolve \'root\' attribute value \"%s\" in %s", rootValue, self.__SystemDefinitionFile)
+							return
+
+				group = generic_path.Path(bldFileValue)
+
+				if self.__Version['MAJOR'] < 3:
+					# absolute paths are not changed by root var in 1.x and 2.x
+					if not group.isAbsolute() and bldInfRoot:
+						group = generic_path.Join(bldInfRoot, group)
 				else:
-					component = self.__CreateComponent(bldinf, aElement)
-					layer = component.GetContainerName("layer")
-					if layer:
-						self.__LayerDetails[layer].append(component)
-						self.__TotalComponents += 1
-					else:
-						self.__Logger.Error("No containing layer found for %s in %s", str(bldinf), self.__SystemDefinitionFile)
-
-		# search the sub-elements
-		for child in aElement.childNodes:
-			if child.nodeType == child.ELEMENT_NODE:
-				self.__ProcessSystemModelElement(child)
-
-
-# end of the raptor_xml module
+					# only absolute paths are changed by root var in 3.x
+					if group.isAbsolute() and bldInfRoot:
+						group = generic_path.Join(bldInfRoot, group)
+
+				bldinf = generic_path.Join(group, "bld.inf").FindCaseless()
+
+				if bldinf == None:
+					self.__Logger.Error("No bld.inf found at %s in %s", group.GetLocalString(), self.__SystemDefinitionFile)
+				else:
+					component = self.__CreateComponent(bldinf, aElement)
+					layer = component.GetLayerName()
+					if layer:
+						self.__LayerDetails[layer].append(component)
+						self.__TotalComponents += 1
+					else:
+						self.__Logger.Error("No containing layer found for %s in %s", str(bldinf), self.__SystemDefinitionFile)
+
+		# search the sub-elements
+		for child in aElement.childNodes:
+			if child.nodeType == child.ELEMENT_NODE:
+				self.__ProcessSystemModelElement(child)
+
+
+# end of the raptor_xml module