Web MIDI: MidiManager crashes if a session is ended while initializing

media/midi/midi_manager.h

 // Copyright (c) 2013 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_MIDI_MIDI_MANAGER_H_
 #define MEDIA_MIDI_MIDI_MANAGER_H_
 
 #include <map>
 #include <set>
 #include <vector>
@@ skipping 123 matching lines @@
   void ReceiveMidiData(uint32 port_index,
                        const uint8* data,
                        size_t length,
                        base::TimeTicks time) {
     ReceiveMidiData(port_index, data, length,
                     (time - base::TimeTicks()).InSecondsF());
   }
 
   size_t clients_size_for_testing() const { return clients_.size(); }
   size_t pending_clients_size_for_testing() const {
-    return pending_clients_.size();
+    return pending_clients_size_;
   }
 
  private:
   void CompleteInitializationInternal(MidiResult result);
 
   // Keeps track of all clients who wish to receive MIDI data.
   typedef std::set<MidiManagerClient*> ClientList;
   ClientList clients_;
 
   // Keeps track of all clients who are waiting for CompleteStartSession().
-  typedef std::map<int, MidiManagerClient*> PendingClientMap;
+  typedef std::map<MidiManagerClient*, std::vector<int> > PendingClientMap;

[yhirano, 2014/06/11 12:11:57]

[opt] You can use std::multimap<K, V> instead of std::map<K, std::vector<V>>. If
you do so, you can remove pending_clients_size_.

[Takashi Toyoshima, 2014/06/12 04:41:02]

Done.

   PendingClientMap pending_clients_;
+  size_t pending_clients_size_;
 
   // Keeps a SingleThreadTaskRunner of the thread that calls StartSession in
   // order to invoke CompleteStartSession() on the thread.
   scoped_refptr<base::SingleThreadTaskRunner> session_thread_runner_;
 
   // Keeps true if platform dependent initialization is already completed.
   bool initialized_;
 
   // Keeps the platform dependent initialization result if initialization is
   // completed. Otherwise keeps MIDI_NOT_SUPPORTED.
   MidiResult result_;
 
   // Protects access to |clients_|, |pending_clients_|, |initialized_|, and
   // |result_|.
   base::Lock lock_;
 
   MidiPortInfoList input_ports_;
   MidiPortInfoList output_ports_;
 
   DISALLOW_COPY_AND_ASSIGN(MidiManager);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_MIDI_MIDI_MANAGER_H_