Fix incorrect types in TypedData_Get_Struct for node_type accessors.

attr_decl used xmlAttr instead of xmlAttribute, document used xmlNode
instead of xmlDoc. Both worked by accident because libxml2 places the
type field at the same offset in all node-like structs.

Author: cfis

ext/libxml/ruby_xml_attr_decl.c

@@ -88,8 +88,8 @@ static VALUE rxml_attr_decl_next_get(VALUE self)
  */
 static VALUE rxml_attr_decl_node_type(VALUE self)
 {
-  xmlAttrPtr xattr;
-  TypedData_Get_Struct(self, xmlAttr, &rxml_attr_decl_type, xattr);
+  xmlAttributePtr xattr;
+  TypedData_Get_Struct(self, xmlAttribute, &rxml_attr_decl_type, xattr);
   return INT2NUM(xattr->type);
 }
 

ext/libxml/ruby_xml_document.c

@@ -632,9 +632,9 @@ static VALUE rxml_document_next_q(VALUE self)
  */
 static VALUE rxml_document_node_type(VALUE self)
 {
-  xmlNodePtr xnode;
-  TypedData_Get_Struct(self, xmlNode, &rxml_document_data_type, xnode);
-  return (INT2NUM(xnode->type));
+  xmlDocPtr xdoc;
+  TypedData_Get_Struct(self, xmlDoc, &rxml_document_data_type, xdoc);
+  return (INT2NUM(xdoc->type));
 }
 
 /*