1 files changed, 129 insertions, 0 deletions
diff --git a/dom/storage/StorageNotifierService.cpp b/dom/storage/StorageNotifierService.cpp
new file mode 100644
index 0000000000..57b1ef6bc3
--- /dev/null
+++ b/dom/storage/StorageNotifierService.cpp
@@ -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/. */
+
+#include "StorageNotifierService.h"
+#include "StorageUtils.h"
+#include "mozilla/dom/StorageEvent.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/StaticPtr.h"
+#include "nsThreadUtils.h"
+
+namespace mozilla::dom {
+
+namespace {
+
+// This boolean is used to avoid the creation of the service after been
+// distroyed on shutdown.
+bool gStorageShuttingDown = false;
+
+StaticRefPtr<StorageNotifierService> gStorageNotifierService;
+
+}  // namespace
+
+/* static */
+StorageNotifierService* StorageNotifierService::GetOrCreate() {
+  MOZ_ASSERT(NS_IsMainThread());
+  if (!gStorageNotifierService && !gStorageShuttingDown) {
+    gStorageNotifierService = new StorageNotifierService();
+    ClearOnShutdown(&gStorageNotifierService);
+  }
+
+  return gStorageNotifierService;
+}
+
+StorageNotifierService::StorageNotifierService() {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(!gStorageNotifierService);
+}
+
+StorageNotifierService::~StorageNotifierService() {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(!gStorageNotifierService);
+  gStorageShuttingDown = true;
+}
+
+/* static */
+void StorageNotifierService::Broadcast(StorageEvent* aEvent,
+                                       const char16_t* aStorageType,
+                                       bool aPrivateBrowsing,
+                                       bool aImmediateDispatch) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  RefPtr<StorageNotifierService> service = gStorageNotifierService;
+  if (!service) {
+    return;
+  }
+
+  RefPtr<StorageEvent> event = aEvent;
+
+  for (const auto& observer : service->mObservers.ForwardRange()) {
+    // Enforce that the source storage area's private browsing state matches
+    // this window's state.  These flag checks and their maintenance independent
+    // from the principal's OriginAttributes matter because chrome docshells
+    // that are part of private browsing windows can be private browsing without
+    // having their OriginAttributes set (because they have the system
+    // principal).
+    if (aPrivateBrowsing != observer->IsPrivateBrowsing()) {
+      continue;
+    }
+
+    // No reasons to continue if the principal of the event doesn't match with
+    // the window's one.
+    if (!StorageUtils::PrincipalsEqual(
+            aEvent->GetPrincipal(), observer->GetEffectiveStoragePrincipal())) {
+      continue;
+    }
+
+    const auto pinnedObserver = observer;
+
+    RefPtr<Runnable> r = NS_NewRunnableFunction(
+        "StorageNotifierService::Broadcast",
+        [pinnedObserver, event, aStorageType, aPrivateBrowsing,
+         aImmediateDispatch]() {
+          // Check principals again. EffectiveStoragePrincipal may be changed
+          // when relaxed.
+          if (!aImmediateDispatch &&
+              !StorageUtils::PrincipalsEqual(
+                  event->GetPrincipal(),
+                  pinnedObserver->GetEffectiveStoragePrincipal())) {
+            return;
+          }
+
+          pinnedObserver->ObserveStorageNotification(event, aStorageType,
+                                                     aPrivateBrowsing);
+        });
+
+    if (aImmediateDispatch) {
+      r->Run();
+    } else {
+      nsCOMPtr<nsIEventTarget> et = pinnedObserver->GetEventTarget();
+      if (et) {
+        et->Dispatch(r.forget());
+      }
+    }
+  }
+}
+
+void StorageNotifierService::Register(StorageNotificationObserver* aObserver) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aObserver);
+  MOZ_ASSERT(!mObservers.Contains(aObserver));
+
+  mObservers.AppendElement(aObserver);
+}
+
+void StorageNotifierService::Unregister(
+    StorageNotificationObserver* aObserver) {
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aObserver);
+
+  // No assertion about mObservers containing aObserver because window calls
+  // this method multiple times.
+
+  mObservers.RemoveElement(aObserver);
+}
+
+}  // namespace mozilla::dom