Line data    Source code

       1             : /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
       2             : /* vim: set sw=4 ts=8 et tw=80 : */
       3             : /* This Source Code Form is subject to the terms of the Mozilla Public
       4             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       5             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
       6             : 
       7             : #ifndef mozilla_layers_LayerTreeOwnerTracker_h
       8             : #define mozilla_layers_LayerTreeOwnerTracker_h
       9             : 
      10             : #include "base/process.h"  // for base::ProcessId
      11             : #include "mozilla/Mutex.h" // for mozilla::Mutex
      12             : 
      13             : #include <functional>
      14             : #include <map>
      15             : 
      16             : namespace mozilla {
      17             : 
      18             : namespace dom {
      19             :   class ContentParent;
      20             : }
      21             : 
      22             : namespace layers {
      23             : 
      24             : /**
      25             :  * A utility class for tracking which content processes should be allowed
      26             :  * to access which layer trees.
      27             :  *
      28             :  * ProcessId's are used to track which content process can access the layer
      29             :  * tree, and in the case of nested browser's we use the top level content
      30             :  * processes' ProcessId.
      31             :  *
      32             :  * This class is only available in the main process and gpu process. Mappings
      33             :  * are synced from main process to the gpu process. The actual syncing happens
      34             :  * in GPUProcessManager, and so this class should not be used directly.
      35             :  */
      36           0 : class LayerTreeOwnerTracker final
      37             : {
      38             : public:
      39             :   static void Initialize();
      40             :   static void Shutdown();
      41             :   static LayerTreeOwnerTracker* Get();
      42             : 
      43             :   /**
      44             :    * Map aLayersId and aProcessId together so that that process
      45             :    * can access that layer tree.
      46             :    */
      47             :   void Map(uint64_t aLayersId, base::ProcessId aProcessId);
      48             : 
      49             :   /**
      50             :   * Remove an existing mapping.
      51             :   */
      52             :   void Unmap(uint64_t aLayersId, base::ProcessId aProcessId);
      53             : 
      54             :   /**
      55             :    * Checks whether it is okay for aProcessId to access aLayersId.
      56             :    */
      57             :   bool IsMapped(uint64_t aLayersId, base::ProcessId aProcessId);
      58             : 
      59             :   void Iterate(const std::function<void(uint64_t aLayersId, base::ProcessId aProcessId)>& aCallback);
      60             : 
      61             : private:
      62             :   LayerTreeOwnerTracker();
      63             : 
      64             :   mozilla::Mutex mLayerIdsLock;
      65             :   std::map<uint64_t, base::ProcessId> mLayerIds;
      66             : };
      67             : 
      68             : } // namespace layers
      69             : } // namespace mozilla
      70             : 
      71             : #endif // mozilla_layers_LayerTreeOwnerTracker_h