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   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  private:
  52   struct TaskInfo {
  53     tracked_objects::Location from_here;
  54     base::Closure closure;
  55     int64 delay_ms;
  56   };
  57
  58   // Returns true if the object is associated with the current thread.
  59   bool IsCurrent() const;
  60
  61   // Handles posting to the message loop if there is one, or the pending queue
  62   // if there isn't.
  63   // NOTE: The given closure will be run *WITHOUT* acquiring the Proxy lock.
  64   //       This only makes sense for user code and completely thread-safe
  65   //       proxy operations (e.g., MessageLoop::QuitClosure).
  66   virtual void PostClosure(const tracked_objects::Location& from_here,
  67                            const base::Closure& closure,
  68                            int64 delay_ms) OVERRIDE;
  69
  70   virtual base::MessageLoopProxy* GetMessageLoopProxy() OVERRIDE;
  71
  72   // TLS destructor function.
  73   static void ReleaseMessageLoop(void* value);
  74
  75   // Created when we attach to the current thread, since MessageLoop assumes
  76   // that it's created on the thread it will run on. NULL for the main thread
  77   // loop, since that's owned by somebody else. This is needed for Run and Quit.
  78   // Any time we post tasks, we should post them using loop_proxy_.
  79   scoped_ptr<base::MessageLoop> loop_;
  80   scoped_refptr<base::MessageLoopProxy> loop_proxy_;
  81
  82   // Number of invocations of Run currently on the stack.
  83   int nested_invocations_;
  84
  85   // Set to true when the message loop is destroyed to prevent forther
  86   // posting of work.
  87   bool destroyed_;
  88
  89   // Set to true if all message loop invocations should exit and that the
  90   // loop should be destroyed once it reaches the outermost Run invocation.
  91   bool should_destroy_;
  92
  93   bool is_main_thread_loop_;
  94
  95   // Since we allow tasks to be posted before the message loop is actually
  96   // created (when it's associated with a thread), we keep tasks posted here
  97   // until that happens. Once the loop_ is created, this is unused.
  98   std::vector<TaskInfo> pending_tasks_;
  99
 100   DISALLOW_COPY_AND_ASSIGN(MessageLoopResource);
 101 };
 102
 103 class PPB_MessageLoop_Proxy : public InterfaceProxy {
 104  public:
 105   explicit PPB_MessageLoop_Proxy(Dispatcher* dispatcher);
 106   virtual ~PPB_MessageLoop_Proxy();
 107
 108   static const PPB_MessageLoop_1_0* GetInterface();
 109
 110  private:
 111   DISALLOW_COPY_AND_ASSIGN(PPB_MessageLoop_Proxy);
 112 };
 113
 114 }  // namespace proxy
 115 }  // namespace ppapi
 116
 117 #endif  // PPAPI_PROXY_PPB_MESSAGE_LOOP_PROXY_H_