1 files changed, 76 insertions, 0 deletions
diff --git a/dom/base/IdleDeadline.cpp b/dom/base/IdleDeadline.cpp
new file mode 100644
index 0000000000..ac9cbdbe03
--- /dev/null
+++ b/dom/base/IdleDeadline.cpp
@@ -0,0 +1,76 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/IdleDeadline.h"
+
+#include <algorithm>
+
+#include "mozilla/dom/Document.h"
+#include "mozilla/dom/IdleDeadlineBinding.h"
+#include "mozilla/dom/Performance.h"
+#include "nsCOMPtr.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsDOMNavigationTiming.h"
+#include "nsPIDOMWindow.h"
+
+namespace mozilla::dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(IdleDeadline, mWindow, mGlobal)
+NS_IMPL_CYCLE_COLLECTING_ADDREF(IdleDeadline)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(IdleDeadline)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(IdleDeadline)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+NS_INTERFACE_MAP_END
+
+IdleDeadline::IdleDeadline(nsPIDOMWindowInner* aWindow, bool aDidTimeout,
+                           DOMHighResTimeStamp aDeadline)
+    : mWindow(aWindow), mDidTimeout(aDidTimeout), mDeadline(aDeadline) {
+  bool hasHadSHO;
+  mGlobal = aWindow->GetDoc()->GetScriptHandlingObject(hasHadSHO);
+}
+
+IdleDeadline::IdleDeadline(nsIGlobalObject* aGlobal, bool aDidTimeout,
+                           DOMHighResTimeStamp aDeadline)
+    : mWindow(nullptr),
+      mGlobal(aGlobal),
+      mDidTimeout(aDidTimeout),
+      mDeadline(aDeadline) {}
+
+IdleDeadline::~IdleDeadline() = default;
+
+JSObject* IdleDeadline::WrapObject(JSContext* aCx,
+                                   JS::Handle<JSObject*> aGivenProto) {
+  return IdleDeadline_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+DOMHighResTimeStamp IdleDeadline::TimeRemaining() {
+  if (mDidTimeout) {
+    return 0.0;
+  }
+
+  if (mWindow) {
+    RefPtr<Performance> performance = mWindow->GetPerformance();
+    if (!performance) {
+      // If there is no performance object the window is partially torn
+      // down, so we can safely say that there is no time remaining.
+      return 0.0;
+    }
+
+    // The web API doesn't expect deadlines > 50ms, but conversion from the
+    // internal API may lead to some rounding errors.
+    return std::min(std::max(mDeadline - performance->Now(), 0.0), 50.0);
+  }
+
+  // If there's no window, we're in a system scope, and can just use
+  // a high-resolution TimeStamp::Now();
+  auto timestamp = TimeStamp::Now() - TimeStamp::ProcessCreation();
+  return std::max(mDeadline - timestamp.ToMilliseconds(), 0.0);
+}
+
+bool IdleDeadline::DidTimeout() const { return mDidTimeout; }
+
+}  // namespace mozilla::dom