Allow updating of the granule position while writing packets

This allows you to have the granule position updated as you go,
helpful when transcoding/repacking files.

Based on bb78fc8 from @andrm

Author: Gagravarr

core/src/main/java/org/gagravarr/ogg/OggPacketWriter.java

@@ -71,9 +71,22 @@ private OggPage getCurrentPage(boolean forceNew) {
     /**
      * Buffers the given packet up ready for
      *  writing to the stream, but doesn't
-     *  write it to disk yet.
+     *  write it to disk yet. The granule
+     *  position is unchanged.
      */
     public void bufferPacket(OggPacket packet) {
+        bufferPacket(packet, currentGranulePosition);
+    }
+    /**
+     * Buffers the given packet up ready for
+     *  writing to the stream, but doesn't
+     *  write it to disk yet. The granule position
+     *  is updated on the page.
+     * If writing the packet requires a new page,
+     *  then the updated granule position only
+     *  applies to the new page
+     */
+    public void bufferPacket(OggPacket packet, long granulePosition) {
         if(closed) {
             throw new IllegalStateException("Can't buffer packets on a closed stream!");
         }
@@ -93,9 +106,11 @@ public void bufferPacket(OggPacket packet) {
             if(pos < size) {
                 page = getCurrentPage(true);
                 page.setIsContinuation();
+                page.setGranulePosition(granulePosition);
             }
             emptyPacket = false;
         }
+        page.setGranulePosition(granulePosition);
         packet.setParent(page);
     }
 

core/src/test/java/org/gagravarr/ogg/TestBasicWrite.java

@@ -23,6 +23,7 @@
 /**
  * Test that we can do basic writing without error
  */
+@SuppressWarnings("resource")
 public class TestBasicWrite extends TestCase {
 	public void testOpen() throws IOException {
 		ByteArrayOutputStream baos = new ByteArrayOutputStream();
@@ -92,9 +93,10 @@ public void testEmptyPages() throws IOException {
 		w.bufferPacket(p);
 		w.flush();
 
-		// And a packet with something in it
+		// And a packet with something in it,
+		//  and with a granule position
 		p = new OggPacket(new byte[] {22});
-		w.bufferPacket(p);
+		w.bufferPacket(p, 54321l);
 		w.close();
 
 		// Check again
@@ -106,6 +108,7 @@ public void testEmptyPages() throws IOException {
 		assertEquals(true, p.isBeginningOfStream());
 		assertEquals(true, p.isEndOfStream());
 		assertEquals(1234, p.getSid());
+                assertEquals(0, p.getGranulePosition());
 		assertEquals(0, p.getSequenceNumber());
 		assertEquals(0, p.getData().length);
 
@@ -114,6 +117,7 @@ public void testEmptyPages() throws IOException {
 		assertEquals(true, p.isBeginningOfStream());
 		assertEquals(false, p.isEndOfStream());
 		assertEquals(54321, p.getSid());
+                assertEquals(0, p.getGranulePosition());
 		assertEquals(0, p.getSequenceNumber());
 		assertEquals(0, p.getData().length);
 
@@ -122,6 +126,7 @@ public void testEmptyPages() throws IOException {
 		assertEquals(false, p.isBeginningOfStream());
 		assertEquals(true, p.isEndOfStream());
 		assertEquals(54321, p.getSid());
+                assertEquals(54321l, p.getGranulePosition());
 		assertEquals(1, p.getSequenceNumber());
 		assertEquals(1, p.getData().length);