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/base/resource_id.h"
  11 #include "cc/resources/returned_resource.h"
  12 #include "cc/resources/transferable_resource.h"
  13 #include "cc/surfaces/surfaces_export.h"
  14
  15 namespace cc {
  16 class SurfaceFactoryClient;
  17
  18 // A SurfaceResourceHolder manages the lifetime of resources submitted by a
  19 // particular SurfaceFactory. Each resource is held by the service until
  20 // it is no longer referenced by any pending frames or by any
  21 // resource providers.
  22 class CC_SURFACES_EXPORT SurfaceResourceHolder {
  23  public:
  24   explicit SurfaceResourceHolder(SurfaceFactoryClient* client);
  25   ~SurfaceResourceHolder();
  26
  27   void ReceiveFromChild(const TransferableResourceArray& resources);
  28   void RefResources(const TransferableResourceArray& resources);
  29   void UnrefResources(const ReturnedResourceArray& resources);
  30
  31  private:
  32   SurfaceFactoryClient* client_;
  33
  34   struct ResourceRefs {
  35     ResourceRefs();
  36
  37     int refs_received_from_child;
  38     int refs_holding_resource_alive;
  39   };
  40   // Keeps track of the number of users currently in flight for each resource
  41   // ID we've received from the client. When this counter hits zero for a
  42   // particular resource, that ID is available to return to the client.
  43   typedef base::hash_map<ResourceId, ResourceRefs> 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_