diff --git a/media/ndk/NdkMediaDataSourcePriv.h b/media/ndk/NdkMediaDataSourcePriv.h
index 8a5423c..16ff974 100644
--- a/media/ndk/NdkMediaDataSourcePriv.h
+++ b/media/ndk/NdkMediaDataSourcePriv.h
@@ -50,6 +50,7 @@
     virtual String8 toString();
     virtual String8 getMIMEType() const;
     virtual void close();
+    virtual status_t getAvailableSize(off64_t offset, off64_t *size);
 
 protected:
     virtual ~NdkDataSource();