chromecast/base/cast_resource.h

   1 // Copyright 2015 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 CHROMECAST_BASE_CAST_RESOURCE_H_
   6 #define CHROMECAST_BASE_CAST_RESOURCE_H_
   7
   8 #include "base/macros.h"
   9
  10 namespace chromecast {
  11
  12 // Interface for resources needed to run application.
  13 class CastResource {
  14  public:
  15   // Resources necessary to run cast apps. CastResource may contain union of the
  16   // following types.
  17   // TODO(yucliu): Split video resources and graphic resources.
  18   enum Resource {
  19     kResourceNone = 0,
  20     // All resources necessary to render sounds, for example, audio pipeline,
  21     // speaker, etc.
  22     kResourceAudio = 1 << 0,
  23     // All resources necessary to render videos or images, for example, video
  24     // pipeline, primary graphics plane, display, etc.
  25     kResourceScreenPrimary = 1 << 1,
  26     // All resources necessary to render overlaid images, for example, secondary
  27     // graphics plane, LCD, etc.
  28     kResourceScreenSecondary = 1 << 2,
  29     // Collection of resources used for display only combined with bitwise or.
  30     kResourceDisplayOnly = (kResourceScreenPrimary | kResourceScreenSecondary),
  31     // Collection of all resources combined with bitwise or.
  32     kResourceAll =
  33         (kResourceAudio | kResourceScreenPrimary | kResourceScreenSecondary),
  34   };
  35
  36   class Client {
  37    public:
  38     // Called when resource is created. CastResource should not be owned by
  39     // Client. It can be called from any thread.
  40     virtual void OnResourceAcquired(CastResource* cast_resource) = 0;
  41     // Called when part or all resources are released. It can be called from any
  42     // thread.
  43     //   |cast_resource| the CastResource that is released. The pointer may be
  44     //                   invalid. Client can't call functions with that pointer.
  45     //   |remain| the unreleased resource of CastResource. If kResourceNone is
  46     //            returned, Client will remove the resource from its watching
  47     //            list.
  48     virtual void OnResourceReleased(CastResource* cast_resource,
  49                                     Resource remain) = 0;
  50
  51    protected:
  52     virtual ~Client() {}
  53   };
  54
  55   CastResource() {}
  56
  57   virtual void SetCastResourceClient(Client* client) = 0;
  58   // Called to release resources. Implementation should call
  59   // Client::OnResourceReleased when resource is released on its side.
  60   virtual void ReleaseResource(Resource resource) = 0;
  61
  62  protected:
  63   virtual ~CastResource() {}
  64
  65  private:
  66   DISALLOW_COPY_AND_ASSIGN(CastResource);
  67 };
  68
  69 }  // namespace chromecast
  70
  71 #endif