Combine 'pssh' parsing routines.

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 83 matching lines @@
   // true. The semantics of |*err| are the same as above.
   //
   // |buf| is not retained.
   static bool StartTopLevelBox(const uint8* buf,
                                const int buf_size,
                                const LogCB& log_cb,
                                FourCC* type,
                                int* box_size,
                                bool* err) WARN_UNUSED_RESULT;
 
+  // Create a BoxReader from a buffer. |buf| must be the complete buffer, as
+  // errors are returned when sufficient data is not available. |buf| can start
+  // with any type of box -- it does not have to be IsValidTopLevelBox().
+  //
+  // |buf| is retained but not owned, and must outlive the BoxReader instance.
+  static BoxReader* ReadConcatentatedBoxes(const uint8* buf,
+                                           const int buf_size);
+
   // 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;
 
@@ skipping 27 matching lines @@
   // the box has been initialized, and does not re-read the main box header.
   bool ReadFullBoxHeader() WARN_UNUSED_RESULT;
 
   FourCC type() const   { return type_; }
   uint8 version() const { return version_; }
   uint32 flags() const  { return flags_; }
 
   const LogCB& log_cb() const { return log_cb_; }
 
  private:
-  BoxReader(const uint8* buf, const int size, const LogCB& log_cb);
+  BoxReader(const uint8* buf, const int size, const LogCB& log_cb, bool is_EOS);

[ddorwin, 2015/06/04 18:08:45]

Should probably explain is_EOS here.

[jrummell, 2015/06/04 21:47:10]

Done.

 
   // Must be called immediately after init. If the return is false, this
   // indicates that the box header and its contents were not available in the
   // stream or were nonsensical, and that the box must not be used further. In
   // this case, if |*err| is false, the problem was simply a lack of data, and
   // should only be an error condition if some higher-level component knows that
   // no more data is coming (i.e. EOS or end of containing box). If |*err| is
   // true, the error is unrecoverable and the stream should be aborted.
   bool ReadHeader(bool* err);
 
   LogCB log_cb_;
   FourCC type_;
   uint8 version_;
   uint32 flags_;
 
   typedef std::multimap<FourCC, BoxReader> ChildMap;
 
   // The set of child box FourCCs and their corresponding buffer readers. Only
   // valid if scanned_ is true.
   ChildMap children_;
   bool scanned_;
+
+  // Set to true if the buffer provided to the reader is the complete stream.

[ddorwin, 2015/06/04 18:08:45]

Drop "Set to " since we don't intend for it to be set other than during
construction.

[jrummell, 2015/06/04 21:47:11]

Done.

+  bool is_EOS_;

[ddorwin, 2015/06/04 18:08:45]

const?

[jrummell, 2015/06/04 21:47:10]

Done.

 };
 
 // Template definitions
 template<typename T> bool BoxReader::ReadChildren(std::vector<T>* children) {
   RCHECK(MaybeReadChildren(children) && !children->empty());
   return true;
 }
 
 template<typename T>
 bool BoxReader::MaybeReadChildren(std::vector<T>* children) {
@@ skipping 17 matching lines @@
            << FourCCToString(child_type) << " boxes.";
   return true;
 }
 
 template<typename T>
 bool BoxReader::ReadAllChildren(std::vector<T>* children) {
   DCHECK(!scanned_);
   scanned_ = true;
 
   bool err = false;
-  while (pos() < size()) {
-    BoxReader child_reader(&buf_[pos_], size_ - pos_, log_cb_);
+  while (pos_ < size_) {
+    BoxReader child_reader(&buf_[pos_], size_ - pos_, log_cb_, is_EOS_);
     if (!child_reader.ReadHeader(&err)) break;
     T child;
     RCHECK(child.Parse(&child_reader));
     children->push_back(child);
     pos_ += child_reader.size();
   }
 
   return !err;
 }
 
 }  // namespace mp4
 }  // namespace media
 
 #endif  // MEDIA_FORMATS_MP4_BOX_READER_H_