Support parsing of sgpd and sbgp boxes

media/formats/mp4/box_reader.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_FORMATS_MP4_BOX_READER_H_
 #define MEDIA_FORMATS_MP4_BOX_READER_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 90 matching lines @@
   // Returns true if |type| is recognized to be a top-level box, false
   // otherwise. This returns true for some boxes which we do not parse.
   // Helpful in debugging misaligned appends.
   static bool IsValidTopLevelBox(const FourCC& type,
                                  const LogCB& log_cb);
 
   // Scan through all boxes within the current box, starting at the current
   // buffer position. Must be called before any of the *Child functions work.
   bool ScanChildren() WARN_UNUSED_RESULT;
 
+  // Return true if child with type |child.BoxType()| exists.
+  bool HasChild(Box* child) WARN_UNUSED_RESULT;
+
   // Read exactly one child box from the set of children. The type of the child
   // will be determined by the BoxType() method of |child|.
   bool ReadChild(Box* child) WARN_UNUSED_RESULT;
 
   // Read one child if available. Returns false on error, true on successful
   // read or on child absent.
   bool MaybeReadChild(Box* child) WARN_UNUSED_RESULT;
 
   // Read at least one child. False means error or no such child present.
   template<typename T> bool ReadChildren(
@@ skipping 87 matching lines @@
     pos_ += child_reader.size();
   }
 
   return !err;
 }
 
 }  // namespace mp4
 }  // namespace media
 
 #endif  // MEDIA_FORMATS_MP4_BOX_READER_H_