Initial import of Dillo

lout/identity.cc

@@ -0,0 +1,131 @@
+/*
+ * Dillo Widget
+ *
+ * Copyright 2005-2007 Sebastian Geerken <sgeerken@dillo.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "identity.hh"
+
+#include <stdio.h>
+
+namespace lout {
+namespace identity {
+
+// ------------------------
+//    IdentifiableObject
+// ------------------------
+
+using namespace object;
+using namespace container::typed;
+
+IdentifiableObject::Class::Class (IdentifiableObject::Class *parent, int id,
+                                  const char *className)
+{
+   this->parent = parent;
+   this->id = id;
+   this->className = className;
+}
+
+void IdentifiableObject::Class::intoStringBuffer(misc::StringBuffer *sb)
+{
+   sb->append ("<class ");
+   sb->append (className);
+   sb->append (" (");
+   sb->appendInt (id);
+   sb->append (")");
+
+   if (parent) {
+      sb->append (", parent: ");
+      parent->intoStringBuffer (sb);
+   }
+
+   sb->append (">");
+}
+
+HashTable <ConstString, IdentifiableObject::Class>
+   *IdentifiableObject::classesByName =
+      new HashTable<ConstString, IdentifiableObject::Class> (true, true);
+Vector <IdentifiableObject::Class> *IdentifiableObject::classesById =
+   new Vector <IdentifiableObject::Class> (16, false);
+IdentifiableObject::Class *IdentifiableObject::currentlyConstructedClass;
+
+IdentifiableObject::IdentifiableObject ()
+{
+   currentlyConstructedClass = NULL;
+}
+
+void IdentifiableObject::intoStringBuffer(misc::StringBuffer *sb)
+{
+   sb->append("<instance ");
+   sb->appendPointer(this);
+   sb->append(" of ");
+   sb->append(getClassName());
+   sb->append(">");
+}
+
+/**
+ * \brief This method must be called in the constructor for the sub class.
+ *    See class comment for details.
+ */
+void IdentifiableObject::registerName (const char *className, int *classId)
+{
+   ConstString str (className);
+   Class *klass = classesByName->get (&str);
+   if (klass == NULL) {
+      klass = new Class (currentlyConstructedClass, classesById->size (),
+                         className);
+      ConstString *key = new ConstString (className);
+      classesByName->put (key, klass);
+      classesById->put (klass);
+      *classId = klass->id;
+   }
+
+   this->classId = klass->id;
+   *classId = klass->id;
+   currentlyConstructedClass = klass;
+}
+
+/**
+ * \brief Returns, whether this class is an instance of the class, given by
+ *    \em otherClassId, or of a sub class of this class.
+ */
+bool IdentifiableObject::instanceOf (int otherClassId)
+{
+   if (otherClassId == -1)
+      // Other class has not been registered yet, while it should have been,
+      // if this class is an instance of it or of a sub-class.
+      return false;
+
+   Class *otherClass = classesById->get (otherClassId);
+
+   if (otherClass == NULL) {
+      fprintf (stderr,
+               "WARNING: Something got wrong here, it seems that a "
+               "CLASS_ID was not initialized properly.\n");
+      return false;
+   }
+
+   for (Class *klass = classesById->get (classId); klass != NULL;
+        klass = klass->parent) {
+      if (klass == otherClass)
+         return true;
+   }
+
+   return false;
+}
+
+} // namespace identity
+} // namespace lout