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 PPAPI_PROXY_PPB_MESSAGE_LOOP_PROXY_H_
6#define PPAPI_PROXY_PPB_MESSAGE_LOOP_PROXY_H_
7
8#include "base/basictypes.h"
9#include "base/bind.h"
10#include "base/memory/ref_counted.h"
11#include "base/memory/scoped_ptr.h"
12#include "base/message_loop/message_loop.h"
13#include "ppapi/proxy/interface_proxy.h"
14#include "ppapi/proxy/ppapi_proxy_export.h"
15#include "ppapi/shared_impl/ppb_message_loop_shared.h"
16#include "ppapi/thunk/ppb_message_loop_api.h"
17
18struct PPB_MessageLoop_1_0;
19
20namespace ppapi {
21namespace proxy {
22
23class PPAPI_PROXY_EXPORT MessageLoopResource : public MessageLoopShared {
24 public:
25  explicit MessageLoopResource(PP_Instance instance);
26  // Construct the one MessageLoopResource for the main thread. This must be
27  // invoked on the main thread.
28  explicit MessageLoopResource(ForMainThread);
29  virtual ~MessageLoopResource();
30
31  // Resource overrides.
32  virtual thunk::PPB_MessageLoop_API* AsPPB_MessageLoop_API() OVERRIDE;
33
34  // PPB_MessageLoop_API implementation.
35  virtual int32_t AttachToCurrentThread() OVERRIDE;
36  virtual int32_t Run() OVERRIDE;
37  virtual int32_t PostWork(PP_CompletionCallback callback,
38                           int64_t delay_ms) OVERRIDE;
39  virtual int32_t PostQuit(PP_Bool should_destroy) OVERRIDE;
40
41  static MessageLoopResource* GetCurrent();
42  void DetachFromThread();
43  bool is_main_thread_loop() const {
44    return is_main_thread_loop_;
45  }
46
47  const scoped_refptr<base::MessageLoopProxy>& message_loop_proxy() {
48    return loop_proxy_;
49  }
50
51  void set_currently_handling_blocking_message(bool handling_blocking_message) {
52    currently_handling_blocking_message_ = handling_blocking_message;
53  }
54
55 private:
56  struct TaskInfo {
57    tracked_objects::Location from_here;
58    base::Closure closure;
59    int64 delay_ms;
60  };
61
62  // Returns true if the object is associated with the current thread.
63  bool IsCurrent() const;
64
65  // MessageLoopShared implementation.
66  //
67  // Handles posting to the message loop if there is one, or the pending queue
68  // if there isn't.
69  // NOTE: The given closure will be run *WITHOUT* acquiring the Proxy lock.
70  //       This only makes sense for user code and completely thread-safe
71  //       proxy operations (e.g., MessageLoop::QuitClosure).
72  virtual void PostClosure(const tracked_objects::Location& from_here,
73                           const base::Closure& closure,
74                           int64 delay_ms) OVERRIDE;
75  virtual base::MessageLoopProxy* GetMessageLoopProxy() OVERRIDE;
76  virtual bool CurrentlyHandlingBlockingMessage() OVERRIDE;
77
78  // TLS destructor function.
79  static void ReleaseMessageLoop(void* value);
80
81  // Created when we attach to the current thread, since MessageLoop assumes
82  // that it's created on the thread it will run on. NULL for the main thread
83  // loop, since that's owned by somebody else. This is needed for Run and Quit.
84  // Any time we post tasks, we should post them using loop_proxy_.
85  scoped_ptr<base::MessageLoop> loop_;
86  scoped_refptr<base::MessageLoopProxy> loop_proxy_;
87
88  // Number of invocations of Run currently on the stack.
89  int nested_invocations_;
90
91  // Set to true when the message loop is destroyed to prevent forther
92  // posting of work.
93  bool destroyed_;
94
95  // Set to true if all message loop invocations should exit and that the
96  // loop should be destroyed once it reaches the outermost Run invocation.
97  bool should_destroy_;
98
99  bool is_main_thread_loop_;
100
101  bool currently_handling_blocking_message_;
102
103  // Since we allow tasks to be posted before the message loop is actually
104  // created (when it's associated with a thread), we keep tasks posted here
105  // until that happens. Once the loop_ is created, this is unused.
106  std::vector<TaskInfo> pending_tasks_;
107
108  DISALLOW_COPY_AND_ASSIGN(MessageLoopResource);
109};
110
111class PPB_MessageLoop_Proxy : public InterfaceProxy {
112 public:
113  explicit PPB_MessageLoop_Proxy(Dispatcher* dispatcher);
114  virtual ~PPB_MessageLoop_Proxy();
115
116  static const PPB_MessageLoop_1_0* GetInterface();
117
118 private:
119  DISALLOW_COPY_AND_ASSIGN(PPB_MessageLoop_Proxy);
120};
121
122}  // namespace proxy
123}  // namespace ppapi
124
125#endif  // PPAPI_PROXY_PPB_MESSAGE_LOOP_PROXY_H_
126