1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4  * License, v. 2.0. If a copy of the MPL was not distributed with this
5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 
7 #include "mozilla/mscom/EnsureMTA.h"
8 
9 #include "mozilla/ClearOnShutdown.h"
10 #include "mozilla/StaticPtr.h"
11 #include "nsThreadUtils.h"
12 
13 #include "private/pprthred.h"
14 
15 namespace {
16 
17 class EnterMTARunnable : public mozilla::Runnable {
18  public:
EnterMTARunnable()19   EnterMTARunnable() : mozilla::Runnable("EnterMTARunnable") {}
Run()20   NS_IMETHOD Run() override {
21     mozilla::DebugOnly<HRESULT> hr =
22         ::CoInitializeEx(nullptr, COINIT_MULTITHREADED);
23     MOZ_ASSERT(SUCCEEDED(hr));
24     return NS_OK;
25   }
26 };
27 
28 class BackgroundMTAData {
29  public:
BackgroundMTAData()30   BackgroundMTAData() {
31     nsCOMPtr<nsIRunnable> runnable = new EnterMTARunnable();
32     mozilla::DebugOnly<nsresult> rv =
33         NS_NewNamedThread("COM MTA", getter_AddRefs(mThread), runnable);
34     NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "NS_NewNamedThread failed");
35     MOZ_ASSERT(NS_SUCCEEDED(rv));
36   }
37 
~BackgroundMTAData()38   ~BackgroundMTAData() {
39     if (mThread) {
40       mThread->Dispatch(
41           NS_NewRunnableFunction("BackgroundMTAData::~BackgroundMTAData",
42                                  &::CoUninitialize),
43           NS_DISPATCH_NORMAL);
44       mThread->Shutdown();
45     }
46   }
47 
GetThread() const48   nsCOMPtr<nsIThread> GetThread() const { return mThread; }
49 
50  private:
51   nsCOMPtr<nsIThread> mThread;
52 };
53 
54 }  // anonymous namespace
55 
56 static mozilla::StaticAutoPtr<BackgroundMTAData> sMTAData;
57 
58 namespace mozilla {
59 namespace mscom {
60 
GetMTAThread()61 /* static */ nsCOMPtr<nsIThread> EnsureMTA::GetMTAThread() {
62   if (!sMTAData) {
63     sMTAData = new BackgroundMTAData();
64     ClearOnShutdown(&sMTAData, ShutdownPhase::ShutdownThreads);
65   }
66   return sMTAData->GetThread();
67 }
68 
69 }  // namespace mscom
70 }  // namespace mozilla
71