Line data    Source code

       1             : /* This Source Code Form is subject to the terms of the Mozilla Public
       2             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       3             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
       4             : 
       5             : #ifndef THREADSAFEREFCOUNTINGWITHMAINTHREADDESTRUCTION_H_
       6             : #define THREADSAFEREFCOUNTINGWITHMAINTHREADDESTRUCTION_H_
       7             : 
       8             : #include "base/message_loop.h"
       9             : #include "MainThreadUtils.h"
      10             : #include "nsThreadUtils.h"
      11             : 
      12             : namespace mozilla {
      13             : namespace layers {
      14             : 
      15           1 : inline MessageLoop* GetMainLoopAssertingMainThread()
      16             : {
      17           1 :   MOZ_ASSERT(NS_IsMainThread());
      18           1 :   return MessageLoop::current();
      19             : }
      20             : 
      21           1 : inline MessageLoop* GetMainLoop()
      22             : {
      23           1 :   static MessageLoop* sMainLoop = GetMainLoopAssertingMainThread();
      24           1 :   return sMainLoop;
      25             : }
      26             : 
      27             : struct HelperForMainThreadDestruction
      28             : {
      29           1 :   HelperForMainThreadDestruction()
      30             :   {
      31           1 :     MOZ_ASSERT(NS_IsMainThread());
      32           1 :     GetMainLoop();
      33           1 :   }
      34             : 
      35           0 :   ~HelperForMainThreadDestruction()
      36             :   {
      37           0 :     MOZ_ASSERT(NS_IsMainThread());
      38           0 :   }
      39             : };
      40             : 
      41             : template<typename T>
      42           0 : struct DeleteOnMainThreadTask : public Runnable
      43             : {
      44             :   T* mToDelete;
      45           0 :   explicit DeleteOnMainThreadTask(T* aToDelete)
      46             :     : Runnable("layers::DeleteOnMainThreadTask")
      47           0 :     , mToDelete(aToDelete)
      48             :   {
      49           0 :   }
      50           0 :   NS_IMETHOD Run() override {
      51           0 :     MOZ_ASSERT(NS_IsMainThread());
      52           0 :     mToDelete->DeleteToBeCalledOnMainThread();
      53           0 :     return NS_OK;
      54             :   }
      55             : };
      56             : 
      57             : } // namespace layers
      58             : } // namespace mozilla
      59             : 
      60             : #define NS_INLINE_DECL_THREADSAFE_REFCOUNTING_WITH_MAIN_THREAD_DESTRUCTION(_class) \
      61             : public:                                                                       \
      62             :   NS_METHOD_(MozExternalRefCountType) AddRef(void) {                          \
      63             :     MOZ_ASSERT_TYPE_OK_FOR_REFCOUNTING(_class)                                \
      64             :     MOZ_ASSERT(int32_t(mRefCnt) >= 0, "illegal refcnt");                      \
      65             :     nsrefcnt count = ++mRefCnt;                                               \
      66             :     NS_LOG_ADDREF(this, count, #_class, sizeof(*this));                       \
      67             :     return (nsrefcnt) count;                                                  \
      68             :   }                                                                           \
      69             :   void DeleteToBeCalledOnMainThread() {                                       \
      70             :     MOZ_ASSERT(NS_IsMainThread());                                            \
      71             :     NS_LOG_RELEASE(this, 0, #_class);                                         \
      72             :     delete this;                                                              \
      73             :   }                                                                           \
      74             :   NS_METHOD_(MozExternalRefCountType) Release(void) {                         \
      75             :     MOZ_ASSERT(int32_t(mRefCnt) > 0, "dup release");                          \
      76             :     nsrefcnt count = --mRefCnt;                                               \
      77             :     if (count == 0) {                                                         \
      78             :       if (NS_IsMainThread()) {                                                \
      79             :         DeleteToBeCalledOnMainThread();                                       \
      80             :       } else {                                                                \
      81             :         NS_DispatchToMainThread(                                              \
      82             :           new mozilla::layers::DeleteOnMainThreadTask<_class>(this));         \
      83             :       }                                                                       \
      84             :     } else {                                                                  \
      85             :       NS_LOG_RELEASE(this, count, #_class);                                   \
      86             :     }                                                                         \
      87             :     return count;                                                             \
      88             :   }                                                                           \
      89             : protected:                                                                    \
      90             :   ::mozilla::ThreadSafeAutoRefCnt mRefCnt;                                    \
      91             : private:                                                                      \
      92             :   ::mozilla::layers::HelperForMainThreadDestruction mHelperForMainThreadDestruction; \
      93             : public:
      94             : 
      95             : #endif