1 files changed, 104 insertions, 0 deletions
diff --git a/gfx/layers/apz/util/APZThreadUtils.h b/gfx/layers/apz/util/APZThreadUtils.h
new file mode 100644
index 000000000..4b9b2c0d0
--- /dev/null
+++ b/gfx/layers/apz/util/APZThreadUtils.h
@@ -0,0 +1,104 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 mozilla_layers_APZThreadUtils_h
+#define mozilla_layers_APZThreadUtils_h
+
+#include "base/message_loop.h"
+#include "nsITimer.h"
+
+namespace mozilla {
+
+class Runnable;
+
+namespace layers {
+
+class APZThreadUtils
+{
+public:
+  /**
+   * In the gtest environment everything runs on one thread, so we
+   * shouldn't assert that we're on a particular thread. This enables
+   * that behaviour.
+   */
+  static void SetThreadAssertionsEnabled(bool aEnabled);
+  static bool GetThreadAssertionsEnabled();
+
+  /**
+   * Set the controller thread.
+   */
+  static void SetControllerThread(MessageLoop* aLoop);
+
+  /**
+   * This can be used to assert that the current thread is the
+   * controller/UI thread (on which input events are received).
+   * This does nothing if thread assertions are disabled.
+   */
+  static void AssertOnControllerThread();
+
+  /**
+   * This can be used to assert that the current thread is the
+   * compositor thread (which applies the async transform).
+   * This does nothing if thread assertions are disabled.
+   */
+  static void AssertOnCompositorThread();
+
+  /**
+   * Run the given task on the APZ "controller thread" for this platform. If
+   * this function is called from the controller thread itself then the task is
+   * run immediately without getting queued.
+   */
+  static void RunOnControllerThread(already_AddRefed<Runnable> aTask);
+
+  /**
+   * Returns true if currently on APZ "controller thread".
+   */
+  static bool IsControllerThread();
+};
+
+// A base class for GenericTimerCallback<Function>.
+// This is necessary because NS_IMPL_ISUPPORTS doesn't work for a class
+// template.
+class GenericTimerCallbackBase : public nsITimerCallback
+{
+public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+
+protected:
+  virtual ~GenericTimerCallbackBase() {}
+};
+
+// An nsITimerCallback implementation that can be used with any function
+// object that's callable with no arguments.
+template <typename Function>
+class GenericTimerCallback final : public GenericTimerCallbackBase
+{
+public:
+  explicit GenericTimerCallback(const Function& aFunction) : mFunction(aFunction) {}
+
+  NS_IMETHOD Notify(nsITimer*) override
+  {
+    mFunction();
+    return NS_OK;
+  }
+private:
+  Function mFunction;
+};
+
+// Convenience function for constructing a GenericTimerCallback.
+// Returns a raw pointer, suitable for passing directly as an argument to
+// nsITimer::InitWithCallback(). The intention is to enable the following
+// terse inline usage:
+//    timer->InitWithCallback(NewTimerCallback([](){ ... }), delay);
+template <typename Function>
+GenericTimerCallback<Function>* NewTimerCallback(const Function& aFunction)
+{
+  return new GenericTimerCallback<Function>(aFunction);
+}
+
+} // namespace layers
+} // namespace mozilla
+
+#endif /* mozilla_layers_APZThreadUtils_h */