Add functions to check if schema id, key names, etc. are valid

They always return true for now, and that's needed for the gconf
migration, but it can be changed later.

gio/gsettings-schema-convert

@@ -20,7 +20,8 @@
 #
 # Authors: Vincent Untz <vuntz@gnome.org>
 
-# TODO: support alias for choice
+# TODO: add alias support for choices
+#       choices: 'this-is-an-alias' = 'real', 'other', 'real'
 
 import os
 import sys
@@ -44,6 +45,34 @@ TYPES_FOR_RANGE = [ 'y', 'n', 'q', 'i', 'u', 'x', 't', 'h', 'd' ]
 ######################################
 
 
+def is_schema_id_valid(id):
+    # FIXME: there's currently no restriction on what an id should contain,
+    # but there might be some later on
+    return True
+
+
+def is_key_name_valid(name):
+    # FIXME: we could check that name is valid ([-a-z0-9], no leading/trailing
+    # -, no leading digit, 32 char max). Note that we don't want to validate
+    # the key when converting from gconf, though, since gconf keys use
+    # underscores.
+    return True
+
+
+def are_choices_valid(choices):
+    # FIXME: we could check that all values have the same type with GVariant
+    return True
+
+
+def is_range_valid(minmax):
+    # FIXME: we'll be able to easily check min < max once we can convert the
+    # values with GVariant
+    return True
+
+
+######################################
+
+
 class GSettingsSchemaConvertException(Exception):
     pass
 
@@ -502,12 +531,14 @@ class SimpleSchemaParser:
     def _token_allow_separator(self):
         return self.current_token in [ 'gettext-domain', 'path', 'l10n', 'summary', 'description', 'choices', 'range' ]
 
-    def _parse_name_without_separator(self):
+    def _parse_id_without_separator(self):
         line = self.unparsed_line
         if line[-1] in self.allowed_separators:
             line = line[:-1].strip()
+        if not is_schema_id_valid(line):
+            raise GSettingsSchemaConvertException('\'%s\' is not a valid schema id.' % line)
+
         self.unparsed_line = ''
-        # FIXME: we could check there's no space
         return line
 
     def _parse_key(self):
@@ -523,8 +554,10 @@ class SimpleSchemaParser:
         if not split:
             raise GSettingsSchemaConvertException('Key \'%s\' cannot be parsed.' % line)
 
-        # FIXME: we could check there's no space
         name = items[0].strip()
+        if not is_key_name_valid(name):
+            raise GSettingsSchemaConvertException('\'%s\' is not a valid key name.' % name)
+
         type = ''
         value = items[1].strip()
         if value[0] == '@':
@@ -562,28 +595,32 @@ class SimpleSchemaParser:
         raise GSettingsSchemaConvertException('Localization \'%s\' cannot be parsed.' % line)
 
     def _parse_choices(self, object):
-        if object.type in TYPES_FOR_CHOICES:
-            line = self.unparsed_line
-            result = [ item.strip() for item in line.split(',') ]
-            self.unparsed_line = ''
-            return result
-        else:
+        if object.type not in TYPES_FOR_CHOICES:
             raise GSettingsSchemaConvertException('Key \'%s\' of type \'%s\' cannot have choices.' % (object.name, object.type))
 
+        line = self.unparsed_line
+        choices = [ item.strip() for item in line.split(',') ]
+        if not are_choices_valid(choices):
+            raise GSettingsSchemaConvertException('\'%s\' is not a valid choice.' % line)
+
+        self.unparsed_line = ''
+        return choices
+
     def _parse_range(self, object):
-        minmax = None
-        if object.type in TYPES_FOR_RANGE:
-            line = self.unparsed_line
-            minmax = [ item.strip() for item in line.split('..') ]
-            if len(minmax) != 2:
-                raise GSettingsSchemaConvertException('Range \'%s\' cannot be parsed.' % line)
-            # FIXME: we'll be able to check min < max once we can convert the
-            # values with GVariant
-            self.unparsed_line = ''
-            return tuple(minmax)
-        else:
+        if object.type not in TYPES_FOR_RANGE:
             raise GSettingsSchemaConvertException('Key \'%s\' of type \'%s\' cannot have a range.' % (object.name, object.type))
 
+        line = self.unparsed_line
+        minmax = [ item.strip() for item in line.split('..') ]
+
+        if len(minmax) != 2:
+            raise GSettingsSchemaConvertException('Range \'%s\' cannot be parsed.' % line)
+        if not is_range_valid(minmax):
+            raise GSettingsSchemaConvertException('\'%s\' is not a valid range.' % line)
+
+        self.unparsed_line = ''
+        return tuple(minmax)
+
     def parse_line(self, line):
         # make sure that lines with only spaces are ignored and considered as
         # empty lines
@@ -648,14 +685,14 @@ class SimpleSchemaParser:
         if self.current_token == 'gettext-domain':
             current_object.gettext_domain = self.unparsed_line
         elif self.current_token == 'schema':
-            name = self._parse_name_without_separator()
+            name = self._parse_id_without_separator()
             new_object = GSettingsSchema()
             new_object.id = name
             current_object.schemas.append(new_object)
         elif self.current_token == 'path':
             current_object.path = self.unparsed_line
         elif self.current_token == 'child':
-            name = self._parse_name_without_separator()
+            name = self._parse_id_without_separator()
             new_object = GSettingsSchemaDir()
             new_object.name = name
             current_object.dirs.append(new_object)