GP-5408 - C++ and PDB - rework hierarchical class layout and VxTable understanding

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/gclass/ClassUtils.java

@@ -0,0 +1,95 @@
+/* ###
+ * IP: GHIDRA
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package ghidra.program.model.gclass;
+
+import ghidra.program.model.data.*;
+
+/**
+ * Utility class for Class-related software modeling.
+ */
+public class ClassUtils {
+
+	// Prototype values for now.  Need to come to agreement on what these should be.  Might want
+	//  a separate one for a generic virtual table (not "base" or "function") for gcc/Itanium
+	//  standard
+	/**
+	 * Standard field name for a virtual base table pointer found within a class
+	 */
+	public static final String VBPTR = "{vbptr}";
+
+	/**
+	 * Standard field name for a virtual function table pointer found within a class
+	 */
+	public static final String VFPTR = "{vfptr}";
+
+	/**
+	 * Type used for {@link #VBPTR} and {@link #VFPTR} fields in a class
+	 */
+	public static final PointerDataType VXPTR_TYPE = new PointerDataType();
+
+	/**
+	 * private constructor -- no instances
+	 */
+	private ClassUtils() {
+		// no instances
+	}
+
+	/**
+	 * Returns the category for class internals
+	 * @param composite the class composite
+	 * @return the category path
+	 */
+	public static CategoryPath getClassInternalsPath(Composite composite) {
+		DataTypePath dtp = composite.getDataTypePath();
+		return new CategoryPath(new CategoryPath(dtp.getCategoryPath(), dtp.getDataTypeName()),
+			"!internal");
+	}
+
+	/**
+	 * Returns the data type path for a suitable base class
+	 * @param composite the class composite
+	 * @return the base class data type path
+	 */
+	public static DataTypePath getBaseClassDataTypePath(Composite composite) {
+		return new DataTypePath(getClassInternalsPath(composite), composite.getName());
+	}
+
+	/**
+	 * Returns the "self-base" composite for the specified class composite.  This could be
+	 * the composite argument itself of could be a component of it
+	 * @param composite the main class type
+	 * @return the self-base composite
+	 */
+	public static Composite getSelfBaseType(Composite composite) {
+		DataTypeManager dtm = composite.getDataTypeManager();
+		DataTypePath dtp = ClassUtils.getBaseClassDataTypePath(composite);
+		DataType dt = dtm.getDataType(dtp);
+		if (dt instanceof Composite base) {
+			return base;
+		}
+		if (composite.getNumComponents() > 0) {
+			DataTypeComponent component = composite.getComponent(0);
+			DataType componentType = component.getDataType();
+			if (componentType instanceof Structure struct) {
+				if (struct.getDataTypePath().equals(dtp)) {
+					return struct;
+				}
+			}
+		}
+		return composite;
+	}
+
+}