core: rename classes for case-insensitive systems (fix #24)

jadx-core/src/main/java/jadx/core/deobf/Deobfuscator.java

@@ -198,11 +198,18 @@ public class Deobfuscator {
 			return;
 		}
 		if (shouldRename(classInfo.getShortName())) {
-			alias = makeClsAlias(cls);
-			clsMap.put(classInfo, new DeobfClsInfo(this, cls, pkg, alias));
+			makeClsAlias(cls);
 		}
 	}
 
+	public String getClsAlias(ClassNode cls) {
+		DeobfClsInfo deobfClsInfo = clsMap.get(cls.getClassInfo());
+		if (deobfClsInfo != null) {
+			return deobfClsInfo.getAlias();
+		}
+		return makeClsAlias(cls);
+	}
+
 	private String makeClsAlias(ClassNode cls) {
 		SourceFileAttr sourceFileAttr = cls.get(AType.SOURCE_FILE);
 		if (sourceFileAttr != null) {
@@ -217,8 +224,13 @@ public class Deobfuscator {
 				return name;
 			}
 		}
-		String clsName = cls.getClassInfo().getShortName();
-		return String.format("C%04d%s", clsIndex++, makeName(clsName));
+		ClassInfo classInfo = cls.getClassInfo();
+		String clsName = classInfo.getShortName();
+		String alias = String.format("C%04d%s", clsIndex++, makeName(clsName));
+
+		PackageNode pkg = getPackageNode(classInfo.getPackage(), true);
+		clsMap.put(classInfo, new DeobfClsInfo(this, cls, pkg, alias));
+		return alias;
 	}
 
 	@Nullable

jadx-core/src/main/java/jadx/core/dex/visitors/RenameVisitor.java

@@ -19,8 +19,12 @@ import java.io.File;
 import java.util.HashSet;
 import java.util.Set;
 
+import org.apache.commons.io.IOCase;
+
 public class RenameVisitor extends AbstractVisitor {
 
+	private static final boolean CASE_SENSITIVE_FS = IOCase.SYSTEM.isCaseSensitive();
+
 	private Deobfuscator deobfuscator;
 
 	@Override
@@ -30,12 +34,9 @@ public class RenameVisitor extends AbstractVisitor {
 		deobfuscator = new Deobfuscator(args, root.getDexNodes(), deobfMapFile);
 		boolean deobfuscationOn = args.isDeobfuscationOn();
 		if (deobfuscationOn) {
-			// TODO: check classes for case sensitive names (issue #24)
 			deobfuscator.execute();
 		}
-		for (ClassNode classNode : root.getClasses(true)) {
-			checkClassName(classNode);
-		}
+		checkClasses(root);
 	}
 
 	@Override
@@ -48,6 +49,23 @@ public class RenameVisitor extends AbstractVisitor {
 		return false;
 	}
 
+	private void checkClasses(RootNode root) {
+		Set<String> clsNames = new HashSet<String>();
+		for (ClassNode cls : root.getClasses(true)) {
+			checkClassName(cls);
+			if (!CASE_SENSITIVE_FS) {
+				ClassInfo classInfo = cls.getClassInfo();
+				String clsFileName = classInfo.getAlias().getFullPath();
+				if (!clsNames.add(clsFileName.toLowerCase())) {
+					String newShortName = deobfuscator.getClsAlias(cls);
+					String newFullName = classInfo.makeFullClsName(newShortName, true);
+					classInfo.rename(cls.dex(), newFullName);
+					clsNames.add(classInfo.getAlias().getFullPath().toLowerCase());
+				}
+			}
+		}
+	}
+
 	private void checkClassName(ClassNode cls) {
 		ClassInfo classInfo = cls.getClassInfo();
 		String clsName = classInfo.getAlias().getShortName();