ppapi/proxy/ppb_message_loop_proxy.h

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