cc/surfaces/surface_resource_holder.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_SURFACES_SURFACE_RESOURCE_HOLDER_H_
   6 #define CC_SURFACES_SURFACE_RESOURCE_HOLDER_H_
   7
   8 #include "base/containers/hash_tables.h"
   9 #include "base/macros.h"
  10 #include "cc/resources/resource_provider.h"
  11 #include "cc/resources/returned_resource.h"
  12 #include "cc/surfaces/surfaces_export.h"
  13
  14 namespace cc {
  15 class SurfaceFactoryClient;
  16
  17 // A SurfaceResourceHolder manages the lifetime of resources submitted by a
  18 // particular SurfaceFactory. Each resource is held by the service until
  19 // it is no longer referenced by any pending frames or by any
  20 // resource providers.
  21 class CC_SURFACES_EXPORT SurfaceResourceHolder {
  22  public:
  23   explicit SurfaceResourceHolder(SurfaceFactoryClient* client);
  24   ~SurfaceResourceHolder();
  25
  26   void ReceiveFromChild(const TransferableResourceArray& resources);
  27   void RefResources(const TransferableResourceArray& resources);
  28   void UnrefResources(const ReturnedResourceArray& resources);
  29
  30  private:
  31   SurfaceFactoryClient* client_;
  32
  33   struct ResourceRefs {
  34     ResourceRefs();
  35
  36     int refs_received_from_child;
  37     int refs_holding_resource_alive;
  38   };
  39   // Keeps track of the number of users currently in flight for each resource
  40   // ID we've received from the client. When this counter hits zero for a
  41   // particular resource, that ID is available to return to the client.
  42   typedef base::hash_map<ResourceProvider::ResourceId, ResourceRefs>
  43       ResourceIdCountMap;
  44   ResourceIdCountMap resource_id_use_count_map_;
  45
  46   DISALLOW_COPY_AND_ASSIGN(SurfaceResourceHolder);
  47 };
  48
  49 }  // namespace cc
  50
  51 #endif  // CC_SURFACES_SURFACE_RESOURCE_HOLDER_H_