streaming detection based on SEEK_END, tested and working in MediaPlayer for ogg streams from SoundPlay live encoder (oggenc)

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@6614 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/media/plugins/ogg/OggReaderPlugin.cpp

@@ -184,6 +184,15 @@ get_seekable(BDataIO * data)
 		// really screwed
 		return 0;
 	}
+	// next try to seek to the end of the stream (absolutely)
+	if (seekable->Seek(0, SEEK_END) < 0) {
+		return 0;
+	}
+	// then seek back to where we started
+	if (seekable->Seek(current, SEEK_SET) < 0) {
+		// really screwed
+		return 0;
+	}
 	return seekable;
 }