core: skip decoding for plain text xml (fix #82)

jadx-core/src/main/java/jadx/api/ResourcesLoader.java

@@ -53,6 +53,7 @@ public final class ResourcesLoader {
 		}
 		ZipFile zipFile = null;
 		InputStream inputStream = null;
+		Object result = null;
 		try {
 			zipFile = new ZipFile(zipRef.getZipFile());
 			ZipEntry entry = zipFile.getEntry(zipRef.getEntryName());
@@ -60,7 +61,7 @@ public final class ResourcesLoader {
 				throw new IOException("Zip entry not found: " + zipRef);
 			}
 			inputStream = new BufferedInputStream(zipFile.getInputStream(entry));
-			return decoder.decode(entry.getSize(), inputStream);
+			result = decoder.decode(entry.getSize(), inputStream);
 		} catch (Exception e) {
 			throw new JadxException("Error decode: " + zipRef.getEntryName(), e);
 		} finally {
@@ -75,6 +76,7 @@ public final class ResourcesLoader {
 				LOG.debug("Error close zip file: {}", zipRef, e);
 			}
 		}
+		return result;
 	}
 
 	static CodeWriter loadContent(final JadxDecompiler jadxRef, final ResourceFile rf) {
@@ -148,7 +150,7 @@ public final class ResourcesLoader {
 		// LOG.debug("Add resource entry: {}, size: {}", name, entry.getSize());
 	}
 
-	private static CodeWriter loadToCodeWriter(InputStream is) throws IOException {
+	public static CodeWriter loadToCodeWriter(InputStream is) throws IOException {
 		CodeWriter cw = new CodeWriter();
 		ByteArrayOutputStream baos = new ByteArrayOutputStream(READ_BUFFER_SIZE);
 		byte[] buffer = new byte[READ_BUFFER_SIZE];

jadx-core/src/main/java/jadx/core/xmlgen/BinaryXMLParser.java

 package jadx.core.xmlgen;
 
+import jadx.api.ResourcesLoader;
 import jadx.core.codegen.CodeWriter;
 import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.nodes.DexNode;
@@ -81,22 +82,30 @@ public class BinaryXMLParser extends CommonBinaryParser {
 	}
 
 	public synchronized CodeWriter parse(InputStream inputStream) throws IOException {
+		is = new ParserStream(inputStream);
+		if (!isBinaryXml()) {
+			return ResourcesLoader.loadToCodeWriter(inputStream);
+		}
 		writer = new CodeWriter();
 		writer.add("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
-		is = new ParserStream(inputStream);
 		firstElement = true;
 		decode();
 		writer.finish();
 		return writer;
 	}
 
-	void decode() throws IOException {
-		if (is.readInt16() != 0x0003) {
-			die("Version is not 3");
-		}
-		if (is.readInt16() != 0x0008) {
-			die("Size of header is not 8");
+	private boolean isBinaryXml() throws IOException {
+		is.mark(4);
+		int v = is.readInt16(); // version
+		int h = is.readInt16(); // header size
+		if (v == 0x0003 && h == 0x0008) {
+			return true;
 		}
+		is.reset();
+		return false;
+	}
+
+	void decode() throws IOException {
 		int size = is.readInt32();
 		while (is.getPos() < size) {
 			int type = is.readInt16();

jadx-core/src/main/java/jadx/core/xmlgen/ParserStream.java

@@ -132,6 +132,17 @@ public class ParserStream {
 		checkPos(expectedOffset, error);
 	}
 
+	public void mark(int len) throws IOException {
+		if (!input.markSupported()) {
+			throw new IOException("Mark not supported for input stream " + input.getClass());
+		}
+		input.mark(len);
+	}
+
+	public void reset() throws IOException {
+		input.reset();
+	}
+
 	@Override
 	public String toString() {
 		return "pos: 0x" + Long.toHexString(readPos);