GP-4703 - MDMang - retry on demangleType

Ghidra/Features/MicrosoftDmang/src/main/java/mdemangler/MDMang.java

@@ -162,22 +162,10 @@ public class MDMang {
 	 * @throws MDException upon parsing error
 	 */
 	public MDDataType demangleType(boolean errorOnRemainingChars) throws MDException {
-		if (mangled == null) {
-			throw new MDException("MDMang: Mangled string is null.");
-		}
 		initState();
-		pushContext();
-		if (peek() != '.') {
-			throw new MDException("MDMang: Mangled string is not that of a type.");
-		}
-		increment();
-		MDDataType mdDataType = MDDataTypeParser.parseDataType(this, false);
+		MDDataType mdDataType = MDDataTypeParser.determineAndParseDataType(this, false);
 		item = mdDataType;
-		if (mdDataType != null) {
-			mdDataType.parse();
-		}
 		int numCharsRemaining = getNumCharsRemaining();
-		popContext();
 		if (errorOnRemainingChars && (numCharsRemaining > 0)) {
 			throw new MDException(
 				"MDMang: characters remain after demangling: " + numCharsRemaining + ".");

Ghidra/Features/MicrosoftDmang/src/main/java/mdemangler/datatype/MDDataTypeParser.java

@@ -17,6 +17,7 @@ package mdemangler.datatype;
 
 import mdemangler.MDException;
 import mdemangler.MDMang;
+import mdemangler.MDMang.ProcessingMode;
 import mdemangler.datatype.complex.*;
 import mdemangler.datatype.extended.*;
 import mdemangler.datatype.modifier.*;
@@ -31,6 +32,52 @@ import mdemangler.object.MDObjectCPP;
  *  by calling the appropriate parser at the appropriate place in the code.
  */
 public class MDDataTypeParser {
+	/**
+	 * This method is only to be used by MDMang itself for the highest level type parsing where
+	 * there is not already a multi-retry. This method checks for the '.' starting character,
+	 * determines the type by calling the {@link #parseDataType(MDMang, boolean)}, parses the type,
+	 * and does the multi-mode retry if there is an exception on the first pass as
+	 * MDMangObjectParser does for generic mangled objects
+	 * @param dmang - the MDMang driver
+	 * @param isHighest - boolean indicating whether something else modifies or names the data
+	 *  type to be parsed, which impacts when certain overloaded CV modifiers can be applied.
+	 * @return - a type derived from MDDataType
+	 * @throws MDException on parsing error
+	 */
+	public static MDDataType determineAndParseDataType(MDMang dmang, boolean isHighest)
+			throws MDException {
+
+		MDDataType dt = null;
+		if (dmang.peek() != '.') {
+			throw new MDException("MDMang: Mangled string is not that of a type.");
+		}
+
+		dmang.setProcessingMode(ProcessingMode.DEFAULT_STANDARD);
+		try {
+			dmang.pushContext();
+			dmang.increment(); // skip the '.'
+			dt = parseDataType(dmang, isHighest);
+			dt.parse();
+			dmang.popContext();
+		}
+		catch (MDException e1) {
+			dmang.resetState();
+			dmang.setProcessingMode(ProcessingMode.LLVM);
+			try {
+				dmang.pushContext();
+				dmang.increment(); // skip the '.'
+				dt = parseDataType(dmang, isHighest);
+				dt.parse();
+				dmang.popContext();
+			}
+			catch (MDException e2) {
+				throw new MDException(
+					"Reason1: " + e1.getMessage().trim() + "; Reason2: " + e2.getMessage().trim());
+			}
+		}
+		return dt;
+	}
+
 	/**
 	 * This method parses all data types.  Specifically, it parses void, data indirect types,
 	 * function indirect types, and all types parsed by parsePrimaryDataType().

Ghidra/Features/MicrosoftDmang/src/test/java/mdemangler/MDMangBaseTest.java

@@ -14992,6 +14992,19 @@ public class MDMangBaseTest extends AbstractGenericTest {
 		demangleAndTest();
 	}
 
+	// Note the suffix seems like an already or partially demangled name.  Note that name0
+	// seems like a plain tag (no closing '@'), there is a regular namespace delimiter "::",
+	// the suffix "3@" is almost like a backreference tag with the '@' closing the full
+	// qualified name... except... we've seen numbers that are beyond the backref range as
+	// here, but also have seen numbers like 18.
+	@Ignore
+	public void testMangledTypeWithNamespaceSuffix() throws Exception {
+		mangled = ".?AT<unnamed-tag>@name0::3@";
+		msTruth = "";
+		mdTruth = msTruth;
+		demangleAndTest();
+	}
+
 	//=====================
 
 	@Test

Ghidra/Features/MicrosoftDmang/src/test/java/mdemangler/MDMangExtraTest.java

@@ -80,4 +80,18 @@ public class MDMangExtraTest extends AbstractGenericTest {
 		assertEquals("k::j::i", qualifications.get(2).toString());
 	}
 
+	// Need to test the demangleType() method to make sure it does the retry with LLVM mode
+	@Test
+	public void testDemangleTypeWithRetry() throws Exception {
+		// Test string taken from MDMangBaseTest
+		String mangled = ".?AW4name0@?name1@name2@@YAX_N@Z@";
+		String truth = "enum `void __cdecl name2::name1(bool)'::name0";
+
+		MDMangGhidra demangler = new MDMangGhidra();
+		MDParsableItem item = demangler.demangleType(mangled, true); // note demangleType()
+
+		String demangled = item.toString();
+		assertEquals(truth, demangled);
+	}
+
 }