- Better parsing of multiple branching constructs.

TODO: No handling of loops yet.

scripts/if2spdl/Spdl.py

@@ -5,40 +5,12 @@
 import If
 from misc import *
 
-def action(protocol, actiontype, rule, fact):
+def action(actiontype, fact):
 	res = actiontype + "_"
 	res += str(fact.step)
 	res += fact.spdl()
-	res += ";\n"
 	return res
 
-def processRole(protocol, role):
-
-	res = ""
-	print "Role", role
-	# initial knowledge
-	for rule in protocol:
-		if role in rule.getActors():
-			for fact in rule.left:
-				if type(fact) == If.PrincipalFact:
-					print fact
-
-
-	# derive message sequence
-	for rule in protocol:
-		if role in rule.getActors():
-			for fact in rule.left:
-				if type(fact) == If.MessageFact:
-					res += action(protocol, "read", rule, fact)
-
-			for fact in rule.right:
-				if type(fact) == If.MessageFact:
-					res += action(protocol, "send", rule, fact)
-
-
-	print res
-	return ""
-
 
 def getRoles(protocol):
 	roles = []
@@ -46,12 +18,142 @@ def getRoles(protocol):
 		roles += rule.getActors()
 	return uniq(roles)
 
+class Role(object):
+	""" Containts a list of rules, to be executed sequentially """
+	def __init__(self,name,actor):
+		self.name = name
+		self.rules = []
+		self.actor = actor
+	
+	def prependRule(self,rule):
+		self.rules = [rule] + self.rules
+
+	def getLength(self):
+		return len(self.rules)
+
+	def getFirst(self):
+		if self.getLength() > 0:
+			return self.rules[0]
+		else:
+			return None
+
+	def getFirstStep(self):
+		return self.getFirst().getStepFrom()
+
+	def getActor(self):
+		return self.actor
+
+	def __str__(self):
+		res = "Role " + self.name + "\n\n"
+		for rule in self.rules:
+			res += str(rule)
+			res += "\n\n"
+		return res
+
+	def spdl(self):
+		res = ""
+		if len(self.rules) == 0:
+			return res
+		res += "role " + self.name + " ("
+		# TODO Insert parameter agents
+		res += ")\n"
+		res += "{\n"
+		# TODO declare constants, variables
+		res += "\n"
+		# Message sequence
+		res += "\t// Knowledge before: " + str(self.rules[0].before.knowledge) + "\n"
+		for rule in self.rules:
+			# Read
+			if rule.readFact != None:
+				res += "\t" + action("read",rule.readFact) + ";\n"
+			# Show knowledge extending for this read
+			res += "\t// Knowledge delta: " + str(rule.before.runknowledge) + " -> " + str(rule.after.runknowledge) + "\n"
+
+
+
+			# Send
+			if rule.sendFact != None:
+				res += "\t" + action("send",rule.sendFact) + ";\n"
+		# TODO claims
+		# Close up
+		res += "}\n\n"
+		return res
+
+	def __cmp__(self,other):
+		return cmp(self.name, other.name)
+
+def extractRoles(protocol):
+	""" Extract the roles of a protocol description. This yields a
+	list of Role objects """
+
+	# Construct full list of rules to do
+	rulestodo = []
+	for rule in protocol:
+		if type(rule) == If.MessageRule:
+			rulestodo.append(rule)
+	
+	# Now process them until none are left
+	# First, we have no rolenames yet
+	rolenames = []
+	roles = []
+	while len(rulestodo) > 0:
+		# Pick one hrule (with the highest step number, maybe)
+		highest = rulestodo[0].getStepFrom()
+		hrule = rulestodo[0]
+		for rule in rulestodo:
+			step = rule.getStepFrom()
+			step = max(step,rule.getStepTo())
+			if step >= highest:
+				highest = step
+				hrule = rule
+		# hrule has been picked. Work back from here
+		# first make up a name
+		if len(hrule.getActors()) != 1:
+			print "Warning: weird actor list for hrule:", hrule.getActors()
+			name = "X"
+			actor = None
+		else:
+			actor = hrule.getActors()[0]
+			name = str(actor)
+			# Remove variable x prefix
+			if len(name) > 1 and name[0] == 'x':
+				name = name[1:]
+
+		# This name is maybe already taken
+		if name in rolenames:
+			# Append counter
+			counter = 2
+			while name + str(counter) in rolenames:
+				counter = counter+1
+			name = name + str(counter)
+
+		rolenames.append(name)
+		role = Role(name,actor)
+		roles.append(role)
+
+		# Transfer to rule
+		role.prependRule(hrule)
+		rulestodo.remove(hrule)
+
+		# Scan for preceding events until none is found
+		scan = True
+		while scan and role.getFirstStep() != -1:
+			scan = False
+			for rule in rulestodo:
+				if actor in rule.getActors() and rule.getStepTo() == role.getFirstStep():
+					# This one works
+					role.prependRule(rule)
+					rulestodo.remove(rule)
+					scan = True
+
+	return roles
+
 def generator(protocol):
-	roles = getRoles(protocol)
-	print "Found",len(protocol),"rules."
-	print "Roles:", roles
+	roles = extractRoles(protocol)
+	roles.sort()
 	res = ""
+	print "Found",len(roles),"roles."
 	for role in roles:
-		res += processRole(protocol,role)
+		res += role.spdl()
 	return res