Add a unified resource tracker shared between the proxy and the impl.

ppapi/shared_impl/resource.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef PPAPI_SHARED_IMPL_RESOURCE_H_
+#define PPAPI_SHARED_IMPL_RESOURCE_H_
+
+#include <stddef.h>  // For NULL.
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "ppapi/c/pp_instance.h"
+#include "ppapi/c/pp_resource.h"
+#include "ppapi/shared_impl/host_resource.h"
+
+// All resource types should be added here. This implements our hand-rolled
+// RTTI system since we don't compile with "real" RTTI.
+#define FOR_ALL_PPAPI_RESOURCE_APIS(F) \
+  F(PPB_AudioConfig_API) \
+  F(PPB_AudioTrusted_API) \
+  F(PPB_Audio_API) \
+  F(PPB_Broker_API) \
+  F(PPB_Buffer_API) \
+  F(PPB_BufferTrusted_API) \
+  F(PPB_Context3D_API) \
+  F(PPB_DirectoryReader_API) \
+  F(PPB_FileChooser_API) \
+  F(PPB_FileIO_API) \
+  F(PPB_FileRef_API) \
+  F(PPB_FileSystem_API) \
+  F(PPB_Find_API) \
+  F(PPB_Flash_Menu_API) \
+  F(PPB_Flash_NetConnector_API) \
+  F(PPB_Flash_TCPSocket_API) \
+  F(PPB_Font_API) \
+  F(PPB_Graphics2D_API) \
+  F(PPB_Graphics3D_API) \
+  F(PPB_ImageData_API) \
+  F(PPB_InputEvent_API) \
+  F(PPB_LayerCompositor_API) \
+  F(PPB_PDFFont_API) \
+  F(PPB_Scrollbar_API) \
+  F(PPB_Surface3D_API) \
+  F(PPB_Transport_API) \
+  F(PPB_URLLoader_API) \
+  F(PPB_URLRequestInfo_API) \
+  F(PPB_URLResponseInfo_API) \
+  F(PPB_VideoCapture_API) \
+  F(PPB_VideoDecoder_API) \
+  F(PPB_VideoLayer_API) \
+  F(PPB_Widget_API)
+
+namespace ppapi {
+
+// Forward declare all the resource APIs.
+namespace thunk {
+#define DECLARE_RESOURCE_CLASS(RESOURCE) class RESOURCE;
+FOR_ALL_PPAPI_RESOURCE_APIS(DECLARE_RESOURCE_CLASS)
+#undef DECLARE_RESOURCE_CLASS
+}  // namespace thunk
+
+class Resource : public base::RefCounted<Resource> {
+ public:
+  // For constructing non-proxied objects. This just takes the associated
+  // instance, and generates a new resource ID. The host resource will be the
+  // same as the newly-generated resource ID.
+  explicit Resource(PP_Instance instance);
+
+  // For constructing proxied objects. This takes the resource generated in
+  // the host side, stores it, and allocates a "local" resource ID for use in
+  // the current process.
+  explicit Resource(const HostResource& host_resource);
+
+  virtual ~Resource();
+
+  PP_Instance pp_instance() const { return host_resource_.instance(); }
+
+  // Returns the resource ID for this object in the current process without
+  // adjusting the refcount. See also GetReference().
+  PP_Resource pp_resource() const { return pp_resource_; }
+
+  // Returns the host resource which identifies the resource in the host side
+  // of the process in the case of proxied objects. For in-process objects,
+  // this just identifies the in-process resource ID & instance.
+  const HostResource& host_resource() { return host_resource_; }
+
+  // Adds a ref on behalf of the plugin and returns the resource ID. This is
+  // normally used when returning a resource to the plugin, where it's
+  // expecting the returned resource to have ownership of a ref passed.
+  // See also pp_resource() to avoid the AddRef.
+  PP_Resource GetReference();
+
+  // Called by the resource tracker when the last reference from the plugin
+  // was released. For a few types of resources, the resource could still
+  // stay alive if there are other references held by the PPAPI implementation
+  // (possibly for callbacks and things).
+  virtual void LastPluginRefWasDeleted();
+
+  // Called by the resource tracker when the instance is going away but the
+  // object is still alive (this is not the common case, since it requires
+  // something in the implementation to be keeping a ref that keeps the
+  // resource alive.
+  //
+  // You will want to override this if your resource does some kind of
+  // background processing (like maybe network loads) on behalf of the plugin
+  // and you want to stop that when the plugin is deleted.
+  //
+  // Be sure to call this version which clears the instance ID.
+  virtual void InstanceWasDeleted();
+
+  // Dynamic casting for this object. Returns the pointer to the given type if
+  // it's supported. Derived classes override the functions they support to
+  // return the interface.
+  #define DEFINE_TYPE_GETTER(RESOURCE) \
+    virtual thunk::RESOURCE* As##RESOURCE();
+  FOR_ALL_PPAPI_RESOURCE_APIS(DEFINE_TYPE_GETTER)
+  #undef DEFINE_TYPE_GETTER
+
+  // Template-based dynamic casting. See specializations below.
+  template <typename T> T* GetAs() { return NULL; }
+
+ private:
+  // See the getters above.
+  PP_Resource pp_resource_;
+  HostResource host_resource_;
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(Resource);
+};
+
+// Template-based dynamic casting. These specializations forward to the
+// AsXXX virtual functions to return whether the given type is supported.
+#define DEFINE_RESOURCE_CAST(RESOURCE) \
+  template<> inline thunk::RESOURCE* Resource::GetAs() { \
+    return As##RESOURCE(); \
+  }
+FOR_ALL_PPAPI_RESOURCE_APIS(DEFINE_RESOURCE_CAST)
+#undef DEFINE_RESOURCE_CAST
+
+}  // namespace ppapi
+
+#endif  // PPAPI_SHARED_IMPL_RESOURCE_H_