Better handling of misnamed MP3/OGG files. (part of #120)

This also catches more MP3 loading errors that could occur and properly cleans up resources.

Signed-off-by: Jeffrey Han <itdelatrisu@gmail.com>

src/org/newdawn/slick/openal/Mp3InputStream.java

@@ -76,15 +76,20 @@ public class Mp3InputStream extends InputStream implements AudioInputStream {
 	/**
 	 * Create a new stream to decode MP3 data.
 	 * @param input the input stream from which to read the MP3 file
+	 * @throws IOException failure to read the header from the input stream
 	 */
-	public Mp3InputStream(InputStream input) {
+	public Mp3InputStream(InputStream input) throws IOException {
 		decoder = new Decoder();
 		bitstream = new Bitstream(input);
 		try {
 			header = bitstream.readFrame();
 		} catch (BitstreamException e) {
 			Log.error(e);
 		}
+		if (header == null) {
+			close();
+			throw new IOException("Failed to read header from MP3 input stream.");
+		}
 
 		channels = (header.mode() == Header.SINGLE_CHANNEL) ? 1 : 2;
 		sampleRate = header.frequency();

src/org/newdawn/slick/openal/OpenALStreamPlayer.java

@@ -152,16 +152,30 @@ private void initStreams() throws IOException {
 		if (url != null) {
 			audio = new OggInputStream(url.openStream());
 		} else {
-			if (ref.toLowerCase().endsWith(".mp3"))
-				audio = new Mp3InputStream(ResourceLoader.getResourceAsStream(ref));
-			else
-				audio = new OggInputStream(ResourceLoader.getResourceAsStream(ref));
-
-			if (audio.getRate() == 0 && audio.getChannels() == 0) {
-				if (ref.toLowerCase().endsWith(".mp3"))
-					audio = new OggInputStream(ResourceLoader.getResourceAsStream(ref));
-				else
+			if (ref.toLowerCase().endsWith(".mp3")) {
+				try {
 					audio = new Mp3InputStream(ResourceLoader.getResourceAsStream(ref));
+				} catch (IOException e) {
+					// invalid MP3: check if file is actually OGG
+					try {
+						audio = new OggInputStream(ResourceLoader.getResourceAsStream(ref));
+					} catch (IOException e1) {
+						throw e;  // invalid OGG: re-throw original MP3 exception
+					}
+					if (audio.getRate() == 0 && audio.getChannels() == 0)
+						throw e;  // likely not OGG: re-throw original MP3 exception
+				}
+			} else {
+				audio = new OggInputStream(ResourceLoader.getResourceAsStream(ref));
+				if (audio.getRate() == 0 && audio.getChannels() == 0) {
+					// invalid OGG: check if file is actually MP3
+					AudioInputStream audioOGG = audio;
+					try {
+						audio = new Mp3InputStream(ResourceLoader.getResourceAsStream(ref));
+					} catch (IOException e) {
+						audio = audioOGG;  // invalid MP3: keep OGG stream
+					}
+				}
 			}
 		}