1// Copyright (c) 2012 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 CONTENT_RENDERER_PEPPER_NPOBJECT_VAR_H_
6#define CONTENT_RENDERER_PEPPER_NPOBJECT_VAR_H_
7
8#include <string>
9
10#include "base/compiler_specific.h"
11#include "ppapi/c/pp_instance.h"
12#include "ppapi/shared_impl/var.h"
13#include "content/common/content_export.h"
14
15typedef struct NPObject NPObject;
16typedef struct _NPVariant NPVariant;
17typedef void* NPIdentifier;
18
19namespace ppapi {
20
21// NPObjectVar -----------------------------------------------------------------
22
23// Represents a JavaScript object Var. By itself, this represents random
24// NPObjects that a given plugin (identified by the resource's module) wants to
25// reference. If two different modules reference the same NPObject (like the
26// "window" object), then there will be different NPObjectVar's (and hence
27// PP_Var IDs) for each module. This allows us to track all references owned by
28// a given module and free them when the plugin exits independently of other
29// plugins that may be running at the same time.
30class NPObjectVar : public Var {
31 public:
32  // You should always use FromNPObject to create an NPObjectVar. This function
33  // guarantees that we maintain the 1:1 mapping between NPObject and
34  // NPObjectVar.
35  NPObjectVar(PP_Instance instance, NPObject* np_object);
36
37  // Var overrides.
38  virtual NPObjectVar* AsNPObjectVar() OVERRIDE;
39  virtual PP_VarType GetType() const OVERRIDE;
40
41  // Returns the underlying NPObject corresponding to this NPObjectVar.
42  // Guaranteed non-NULL.
43  NPObject* np_object() const { return np_object_; }
44
45  // Notification that the instance was deleted, the internal reference will be
46  // zeroed out.
47  void InstanceDeleted();
48
49  // Possibly 0 if the object has outlived its instance.
50  PP_Instance pp_instance() const { return pp_instance_; }
51
52  // Helper function that converts a PP_Var to an object. This will return NULL
53  // if the PP_Var is not of object type or the object is invalid.
54  CONTENT_EXPORT static scoped_refptr<NPObjectVar> FromPPVar(PP_Var var);
55
56 private:
57  virtual ~NPObjectVar();
58
59  // Possibly 0 if the object has outlived its instance.
60  PP_Instance pp_instance_;
61
62  // Guaranteed non-NULL, this is the underlying object used by WebKit. We
63  // hold a reference to this object.
64  NPObject* np_object_;
65
66  DISALLOW_COPY_AND_ASSIGN(NPObjectVar);
67};
68
69}  // ppapi
70
71#endif  // CONTENT_RENDERER_PEPPER_NPOBJECT_VAR_H_
72