1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* vim: set ts=8 sts=2 et sw=2 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 "LayersTypes.h" // for LayersId 12 #include "mozilla/Mutex.h" // for mozilla::Mutex 13 14 #include <functional> 15 #include <map> 16 17 namespace mozilla { 18 19 namespace dom { 20 class ContentParent; 21 } 22 23 namespace layers { 24 25 /** 26 * A utility class for tracking which content processes should be allowed 27 * to access which layer trees. 28 * 29 * ProcessId's are used to track which content process can access the layer 30 * tree, and in the case of nested browser's we use the top level content 31 * processes' ProcessId. 32 * 33 * This class is only available in the main process and gpu process. Mappings 34 * are synced from main process to the gpu process. The actual syncing happens 35 * in GPUProcessManager, and so this class should not be used directly. 36 */ 37 class LayerTreeOwnerTracker final { 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(LayersId aLayersId, base::ProcessId aProcessId); 48 49 /** 50 * Remove an existing mapping. 51 */ 52 void Unmap(LayersId aLayersId, base::ProcessId aProcessId); 53 54 /** 55 * Checks whether it is okay for aProcessId to access aLayersId. 56 */ 57 bool IsMapped(LayersId aLayersId, base::ProcessId aProcessId); 58 59 void Iterate( 60 const std::function<void(LayersId aLayersId, base::ProcessId aProcessId)>& 61 aCallback); 62 63 private: 64 LayerTreeOwnerTracker(); 65 66 mozilla::Mutex mLayerIdsLock; 67 std::map<LayersId, base::ProcessId> mLayerIds; 68 }; 69 70 } // namespace layers 71 } // namespace mozilla 72 73 #endif // mozilla_layers_LayerTreeOwnerTracker_h 74