Name sanitizing for entity names for Protocol Buffers entities.

* If entity names conflicts with ObjectiveC reserved words or some method name (e.g., hash, description), it is renamed.
diff --git a/prefixize.py b/prefixize.py
index 28a5769..affb73f 100644
--- a/prefixize.py
+++ b/prefixize.py
@@ -17,9 +17,17 @@
 class MyVisitor(m.Visitor):
     content=""
     offset=0
+    doNameSanitization=False
     statementsChanged=0
     prefix=""
 
+    reserved = ['auto','else','long','switch','break','enum','register','typedef','case','extern','return',
+                'union','char','float','short','unsigned','const','for','signed','void','continue','goto',
+                'sizeof','volatile','default','if','static','while','do','int','struct','_Packed','double',
+                'protocol','interface','implementation','NSObject','NSInteger','NSNumber','CGFloat','property',
+                'nonatomic', 'retain','strong', 'weak', 'unsafe_unretained', 'readwrite' 'readonly',
+                'hash', 'description', 'id']
+
     def prefixize(self, lu, oldId):
         '''
         Simple frefixization - with constant prefix to all identifiers (flat).
@@ -53,6 +61,37 @@
         self.offset += newCodeLen - oldCodeLen
         self.statementsChanged+=1
 
+    def isNameInvalid(self, name):
+        '''
+        Returns true if name conflicts with objectiveC. It cannot be from the list of a reserved words
+        or starts with init or new.
+        :param name:
+        :return:
+        '''
+        return name in self.reserved or name.startswith('init') or name.startswith('new')
+
+    def sanitizeName(self, obj):
+        '''
+        Replaces entity name if it is considered conflicting.
+        :param obj:
+        :return:
+        '''
+        if not self.doNameSanitization:
+            return
+
+        if isinstance(obj, m.Name):
+            n = str(obj.value)
+            if self.isNameInvalid(n):
+                if self.verbose>1:
+                    print "!!Invalid name: %s, %s" % (n, obj)
+                self.replace(obj.value, 'x'+n)
+
+        elif isinstance(obj, m.LU):
+            return
+
+        else:
+            return
+
     def __init__(self):
         super(MyVisitor, self).__init__()
 
@@ -71,8 +110,17 @@
         '''Ignore'''
         return True
 
+    def visit_LU(self, obj):
+        return True
+
+    def visit_default(self, obj):
+        return True
+
     def visit_FieldDirective(self, obj):
         '''Ignore, Field directive, e.g., default value.'''
+        n = str(obj.name)
+        if n == 'default':
+            self.sanitizeName(obj.value)
         return True
 
     def visit_FieldType(self, obj):
@@ -81,18 +129,21 @@
 
     def visit_FieldDefinition(self, obj):
         '''New field defined in a message, check type, if is name, prefixize.'''
-        if self.verbose > 3:
-            print "\tField: name=%s, lex=%s" % (obj.name, obj.lexspan)
+        if self.verbose > 4:
+            print "\tField: name=%s, lex=%s parent=%s" % (obj.name, obj.lexspan, obj.parent!=None)
 
         if isinstance(obj.ftype, m.Name):
             self.prefixize(obj.ftype, obj.ftype.value)
+            self.sanitizeName(obj.ftype)
 
+        self.sanitizeName(obj.name)
         return True
 
     def visit_EnumFieldDefinition(self, obj):
-        if self.verbose > 3:
+        if self.verbose > 4:
             print "\tEnumField: name=%s, %s" % (obj.name, obj)
 
+        self.sanitizeName(obj.name)
         return True
 
     def visit_EnumDefinition(self, obj):
@@ -109,6 +160,7 @@
             print "Message, [%s] lex=%s body=|%s|\n" % (obj.name, obj.lexspan, obj.body)
 
         self.prefixize(obj.name, str(obj.name.value))
+        self.sanitizeName(obj.name)
         return True
 
     def visit_MessageExtension(self, obj):
@@ -117,12 +169,15 @@
             print "MessageEXT, [%s] body=%s\n\n" % (obj.name, obj.body)
 
         self.prefixize(obj.name, obj.name.value)
+        self.sanitizeName(obj.name)
         return True
 
     def visit_MethodDefinition(self, obj):
+        self.sanitizeName(obj.name)
         return True
 
     def visit_ServiceDefinition(self, obj):
+        self.sanitizeName(obj.name)
         return True
 
     def visit_ExtensionsDirective(self, obj):
@@ -134,6 +189,9 @@
     def visit_Name(self, obj):
         return True
 
+    def visit_DotName(self, obj):
+        return True
+
     def visit_Proto(self, obj):
         return True
        
@@ -145,6 +203,7 @@
     parser.add_argument('-o','--outdir',    help='Output directory', required=False, default="", dest='outdir')
     parser.add_argument('-e','--echo',      help='Writes output to the standard output', required=False, default=False)
     parser.add_argument('-v','--verbose',   help='Writes output to the standard output', required=False, default=0, type=int)
+    parser.add_argument('-s','--sanitize',  help='If set, performs entity name sanitization - renames conflicting names', required=False, default=0, type=int)
     parser.add_argument('file')
     args = parser.parse_args()
     
@@ -158,6 +217,8 @@
         v = MyVisitor()
         v.offset = 0
         v.prefix = args.prefix
+        v.verbose = args.verbose
+        v.doNameSanitization = args.sanitize > 0
         with open(args.file, 'r') as content_file:
             v.content = content_file.read()