message_handler.h revision 1320f92c476a1ad9d19dba2a48c72b75566198e9 
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 PPAPI_PROXY_MESSAGE_HANDLER_H_
6#define PPAPI_PROXY_MESSAGE_HANDLER_H_
7
8#include "base/memory/ref_counted.h"
9#include "base/memory/scoped_ptr.h"
10#include "ppapi/c/dev/ppb_messaging_deprecated.h"
11#include "ppapi/c/pp_resource.h"
12#include "ppapi/c/ppp_message_handler.h"
13#include "ppapi/proxy/ppapi_proxy_export.h"
14
15namespace IPC {
16class Message;
17}
18
19namespace ppapi {
20
21class ScopedPPVar;
22
23namespace proxy {
24
25class MessageLoopResource;
26
27// MessageHandler wraps a PPP_MessageHandler to encapsulate calling methods
28// on the right thread and calling the Destroy function when this
29// MessageHandler is destroyed.
30class PPAPI_PROXY_EXPORT MessageHandler {
31 public:
32  // Create a MessageHandler. If any parameters are invalid, it will return a
33  // null scoped_ptr and set |*error| appropriately.
34  // |handler_if| is the struct of function pointers we will invoke. All of
35  //              the function pointers within must be valid, or we fail
36  //              with PP_ERROR_BADARGUMENT.
37  // |user_data| is a pointer provided by the plugin that we pass back when we
38  //             call functions in |handler_if|.
39  // |message_loop| is the message loop where we will invoke functions in
40  //                |handler_if|. Must not be the main thread message loop,
41  //                to try to force the plugin to not over-subscribe the main
42  //                thread. If it's the main thread loop, |error| will be set
43  //                to PP_ERROR_WRONGTHREAD.
44  // |error| is an out-param that will be set on failure.
45  static scoped_ptr<MessageHandler> Create(
46      PP_Instance instance,
47      const PPP_MessageHandler_0_2* handler_if,
48      void* user_data,
49      PP_Resource message_loop,
50      int32_t* error);
51  // Provide temporary backwards compatibility. TODO(dmichael): Remove all
52  // references to PPB_Messaging_1_1 and PPP_MessageHandler_0_1.
53  // crbug.com/414398
54  static scoped_ptr<MessageHandler> CreateDeprecated(
55      PP_Instance instance,
56      const PPP_MessageHandler_0_1_Deprecated* handler_if,
57      void* user_data,
58      PP_Resource message_loop,
59      int32_t* error);
60  ~MessageHandler();
61
62  bool LoopIsValid() const;
63
64  void HandleMessage(ScopedPPVar var);
65  void HandleBlockingMessage(ScopedPPVar var,
66                             scoped_ptr<IPC::Message> reply_msg);
67
68 private:
69  MessageHandler(PP_Instance instance,
70                 const PPP_MessageHandler_0_2* handler_if,
71                 void* user_data,
72                 scoped_refptr<MessageLoopResource> message_loop);
73  MessageHandler(PP_Instance instance,
74                 const PPP_MessageHandler_0_1_Deprecated* handler_if,
75                 void* user_data,
76                 scoped_refptr<MessageLoopResource> message_loop);
77
78
79  PP_Instance instance_;
80  const PPP_MessageHandler_0_2* handler_if_;
81  const PPP_MessageHandler_0_1_Deprecated* handler_if_0_1_;
82  void* user_data_;
83  scoped_refptr<MessageLoopResource> message_loop_;
84
85  DISALLOW_COPY_AND_ASSIGN(MessageHandler);
86};
87
88}  // namespace proxy
89}  // namespace ppapi
90
91#endif  // PPAPI_PROXY_MESSAGE_HANDLER_H_
92