1 files changed, 129 insertions, 0 deletions
diff --git a/xpcom/threads/TimerThread.h b/xpcom/threads/TimerThread.h
new file mode 100644
index 0000000000..1faa24d318
--- /dev/null
+++ b/xpcom/threads/TimerThread.h
@@ -0,0 +1,129 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef TimerThread_h___
+#define TimerThread_h___
+
+#include "nsIObserver.h"
+#include "nsIRunnable.h"
+#include "nsIThread.h"
+
+#include "nsTimerImpl.h"
+#include "nsThreadUtils.h"
+
+#include "nsTArray.h"
+
+#include "mozilla/Atomics.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/Monitor.h"
+#include "mozilla/ProfilerUtils.h"
+#include "mozilla/UniquePtr.h"
+
+#include <algorithm>
+
+namespace mozilla {
+class TimeStamp;
+}  // namespace mozilla
+
+class TimerThread final : public mozilla::Runnable, public nsIObserver {
+ public:
+  typedef mozilla::Monitor Monitor;
+  typedef mozilla::MutexAutoLock MutexAutoLock;
+  typedef mozilla::TimeStamp TimeStamp;
+  typedef mozilla::TimeDuration TimeDuration;
+
+  TimerThread();
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_NSIRUNNABLE
+  NS_DECL_NSIOBSERVER
+
+  nsresult Shutdown();
+
+  nsresult AddTimer(nsTimerImpl* aTimer, const MutexAutoLock& aProofOfLock)
+      MOZ_REQUIRES(aTimer->mMutex);
+  nsresult RemoveTimer(nsTimerImpl* aTimer, const MutexAutoLock& aProofOfLock)
+      MOZ_REQUIRES(aTimer->mMutex);
+  TimeStamp FindNextFireTimeForCurrentThread(TimeStamp aDefault,
+                                             uint32_t aSearchBound);
+
+  void DoBeforeSleep();
+  void DoAfterSleep();
+
+  bool IsOnTimerThread() const {
+    return mThread->SerialEventTarget()->IsOnCurrentThread();
+  }
+
+  uint32_t AllowedEarlyFiringMicroseconds();
+
+ private:
+  ~TimerThread();
+
+  bool mInitialized;
+
+  // These internal helper methods must be called while mMonitor is held.
+  // AddTimerInternal returns false if the insertion failed.
+  bool AddTimerInternal(nsTimerImpl* aTimer) MOZ_REQUIRES(mMonitor);
+  bool RemoveTimerInternal(nsTimerImpl* aTimer)
+      MOZ_REQUIRES(mMonitor, aTimer->mMutex);
+  void RemoveLeadingCanceledTimersInternal() MOZ_REQUIRES(mMonitor);
+  void RemoveFirstTimerInternal() MOZ_REQUIRES(mMonitor);
+  nsresult Init() MOZ_REQUIRES(mMonitor);
+
+  void PostTimerEvent(already_AddRefed<nsTimerImpl> aTimerRef)
+      MOZ_REQUIRES(mMonitor);
+
+  nsCOMPtr<nsIThread> mThread;
+  // Lock ordering requirements:
+  // (optional) ThreadWrapper::sMutex ->
+  // (optional) nsTimerImpl::mMutex   ->
+  // TimerThread::mMonitor
+  Monitor mMonitor;
+
+  bool mShutdown MOZ_GUARDED_BY(mMonitor);
+  bool mWaiting MOZ_GUARDED_BY(mMonitor);
+  bool mNotified MOZ_GUARDED_BY(mMonitor);
+  bool mSleeping MOZ_GUARDED_BY(mMonitor);
+
+  class Entry final : public nsTimerImplHolder {
+    const TimeStamp mTimeout;
+
+   public:
+    // Entries are created with the TimerImpl's mutex held.
+    // nsTimerImplHolder() will call SetHolder()
+    Entry(const TimeStamp& aMinTimeout, const TimeStamp& aTimeout,
+          nsTimerImpl* aTimerImpl)
+        : nsTimerImplHolder(aTimerImpl),
+          mTimeout(std::max(aMinTimeout, aTimeout)) {}
+
+    nsTimerImpl* Value() const { return mTimerImpl; }
+
+    // Called with the Monitor held, but not the TimerImpl's mutex
+    already_AddRefed<nsTimerImpl> Take() {
+      if (mTimerImpl) {
+        MOZ_ASSERT(mTimerImpl->mHolder == this);
+        mTimerImpl->SetHolder(nullptr);
+      }
+      return mTimerImpl.forget();
+    }
+
+    static bool UniquePtrLessThan(mozilla::UniquePtr<Entry>& aLeft,
+                                  mozilla::UniquePtr<Entry>& aRight) {
+      // This is reversed because std::push_heap() sorts the "largest" to
+      // the front of the heap.  We want that to be the earliest timer.
+      return aRight->mTimeout < aLeft->mTimeout;
+    }
+
+    TimeStamp Timeout() const { return mTimeout; }
+  };
+
+  nsTArray<mozilla::UniquePtr<Entry>> mTimers MOZ_GUARDED_BY(mMonitor);
+  // Set only at the start of the thread's Run():
+  uint32_t mAllowedEarlyFiringMicroseconds MOZ_GUARDED_BY(mMonitor);
+  ProfilerThreadId mProfilerThreadId MOZ_GUARDED_BY(mMonitor);
+};
+
+#endif /* TimerThread_h___ */