1 files changed, 151 insertions, 0 deletions
diff --git a/dom/abort/AbortSignal.cpp b/dom/abort/AbortSignal.cpp
new file mode 100644
index 000000000..38b0a2492
--- /dev/null
+++ b/dom/abort/AbortSignal.cpp
@@ -0,0 +1,151 @@
+/* -*- 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 "AbortSignal.h"
+#include "AbortController.h"
+#include "mozilla/dom/Event.h"
+#include "mozilla/dom/AbortSignalBinding.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(AbortSignal)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(AbortSignal,
+                                                  DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mController)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(AbortSignal,
+                                                DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mController)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(AbortSignal)
+NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
+
+NS_IMPL_ADDREF_INHERITED(AbortSignal, DOMEventTargetHelper)
+NS_IMPL_RELEASE_INHERITED(AbortSignal, DOMEventTargetHelper)
+
+AbortSignal::AbortSignal(AbortController* aController,
+                         bool aAborted)
+  : DOMEventTargetHelper(aController->GetParentObject())
+  , mController(aController)
+  , mAborted(aAborted)
+{}
+
+AbortSignal::AbortSignal(bool aAborted)
+  : mAborted(aAborted)
+{}
+
+JSObject*
+AbortSignal::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
+{
+  return AbortSignalBinding::Wrap(aCx, this, aGivenProto);
+}
+
+bool
+AbortSignal::Aborted() const
+{
+  return mAborted;
+}
+
+void
+AbortSignal::Abort()
+{
+  MOZ_ASSERT(!mAborted);
+  mAborted = true;
+
+  // Let's inform the followers.
+  for (uint32_t i = 0; i < mFollowers.Length(); ++i) {
+    mFollowers[i]->Aborted();
+  }
+
+  EventInit init;
+  init.mBubbles = false;
+  init.mCancelable = false;
+
+  // TODO which kind of event should we dispatch here?
+
+  RefPtr<Event> event =
+    Event::Constructor(this, NS_LITERAL_STRING("abort"), init);
+  event->SetTrusted(true);
+
+  bool dummy;
+  DispatchEvent(event, &dummy);
+}
+
+void
+AbortSignal::AddFollower(AbortSignal::Follower* aFollower)
+{
+  MOZ_DIAGNOSTIC_ASSERT(aFollower);
+  if (!mFollowers.Contains(aFollower)) {
+    mFollowers.AppendElement(aFollower);
+  }
+}
+
+void
+AbortSignal::RemoveFollower(AbortSignal::Follower* aFollower)
+{
+  MOZ_DIAGNOSTIC_ASSERT(aFollower);
+  mFollowers.RemoveElement(aFollower);
+}
+
+bool
+AbortSignal::CanAcceptFollower(AbortSignal::Follower* aFollower) const
+{
+  MOZ_DIAGNOSTIC_ASSERT(aFollower);
+
+  if (!mController) {
+    return true;
+  }
+
+  if (aFollower == mController) {
+    return false;
+  }
+
+  AbortSignal* following = mController->Following();
+  if (!following) {
+    return true;
+  }
+
+  return following->CanAcceptFollower(aFollower);
+}
+
+// AbortSignal::Follower
+// ----------------------------------------------------------------------------
+
+AbortSignal::Follower::~Follower()
+{
+  Unfollow();
+}
+
+void
+AbortSignal::Follower::Follow(AbortSignal* aSignal)
+{
+  MOZ_DIAGNOSTIC_ASSERT(aSignal);
+
+  if (!aSignal->CanAcceptFollower(this)) {
+    return;
+  }
+
+  Unfollow();
+
+  mFollowingSignal = aSignal;
+  aSignal->AddFollower(this);
+}
+
+void
+AbortSignal::Follower::Unfollow()
+{
+  if (mFollowingSignal) {
+    mFollowingSignal->RemoveFollower(this);
+    mFollowingSignal = nullptr;
+  }
+}
+
+} // dom namespace
+} // mozilla namespace