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