diff -r 000000000000 -r 6474c204b198 dom/src/storage/DOMStorageObserver.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/src/storage/DOMStorageObserver.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,345 @@
+/* -*- 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/. */
+
+#include "DOMStorageObserver.h"
+
+#include "DOMStorageDBThread.h"
+#include "DOMStorageCache.h"
+
+#include "nsIObserverService.h"
+#include "nsIURI.h"
+#include "nsIURL.h"
+#include "nsIScriptSecurityManager.h"
+#include "nsIPermission.h"
+#include "nsIIDNService.h"
+#include "mozIApplicationClearPrivateDataParams.h"
+#include "nsICookiePermission.h"
+
+#include "nsPrintfCString.h"
+#include "nsXULAppAPI.h"
+#include "nsEscape.h"
+#include "nsNetCID.h"
+#include "mozilla/Services.h"
+#include "nsServiceManagerUtils.h"
+
+namespace mozilla {
+namespace dom {
+
+static const char kStartupTopic[] = "sessionstore-windows-restored";
+static const uint32_t kStartupDelay = 0;
+
+NS_IMPL_ISUPPORTS(DOMStorageObserver,
+                  nsIObserver,
+                  nsISupportsWeakReference)
+
+DOMStorageObserver* DOMStorageObserver::sSelf = nullptr;
+
+extern nsresult
+CreateReversedDomain(const nsACString& aAsciiDomain, nsACString& aKey);
+
+// static
+nsresult
+DOMStorageObserver::Init()
+{
+  if (sSelf) {
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
+  if (!obs) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  sSelf = new DOMStorageObserver();
+  NS_ADDREF(sSelf);
+
+  // Chrome clear operations.
+  obs->AddObserver(sSelf, kStartupTopic, true);
+  obs->AddObserver(sSelf, "cookie-changed", true);
+  obs->AddObserver(sSelf, "perm-changed", true);
+  obs->AddObserver(sSelf, "browser:purge-domain-data", true);
+  obs->AddObserver(sSelf, "last-pb-context-exited", true);
+  obs->AddObserver(sSelf, "webapps-clear-data", true);
+
+  // Shutdown
+  obs->AddObserver(sSelf, "profile-after-change", true);
+  obs->AddObserver(sSelf, "profile-before-change", true);
+  obs->AddObserver(sSelf, "xpcom-shutdown", true);
+
+  // Observe low device storage notifications.
+  obs->AddObserver(sSelf, "disk-space-watcher", true);
+
+#ifdef DOM_STORAGE_TESTS
+  // Testing
+  obs->AddObserver(sSelf, "domstorage-test-flush-force", true);
+  if (XRE_GetProcessType() == GeckoProcessType_Default) {
+    // Only to forward to child process.
+    obs->AddObserver(sSelf, "domstorage-test-flushed", true);
+  }
+
+  obs->AddObserver(sSelf, "domstorage-test-reload", true);
+#endif
+
+  return NS_OK;
+}
+
+// static
+nsresult
+DOMStorageObserver::Shutdown()
+{
+  if (!sSelf) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  NS_RELEASE(sSelf);
+  return NS_OK;
+}
+
+void
+DOMStorageObserver::AddSink(DOMStorageObserverSink* aObs)
+{
+  mSinks.AppendElement(aObs);
+}
+
+void
+DOMStorageObserver::RemoveSink(DOMStorageObserverSink* aObs)
+{
+  mSinks.RemoveElement(aObs);
+}
+
+void
+DOMStorageObserver::Notify(const char* aTopic, const nsACString& aData)
+{
+  for (uint32_t i = 0; i < mSinks.Length(); ++i) {
+    DOMStorageObserverSink* sink = mSinks[i];
+    sink->Observe(aTopic, aData);
+  }
+}
+
+NS_IMETHODIMP
+DOMStorageObserver::Observe(nsISupports* aSubject,
+                            const char* aTopic,
+                            const char16_t* aData)
+{
+  nsresult rv;
+
+  // Start the thread that opens the database.
+  if (!strcmp(aTopic, kStartupTopic)) {
+    nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
+    obs->RemoveObserver(this, kStartupTopic);
+
+    mDBThreadStartDelayTimer = do_CreateInstance(NS_TIMER_CONTRACTID);
+    if (!mDBThreadStartDelayTimer) {
+      return NS_ERROR_UNEXPECTED;
+    }
+
+    mDBThreadStartDelayTimer->Init(this, nsITimer::TYPE_ONE_SHOT, kStartupDelay);
+
+    return NS_OK;
+  }
+
+  // Timer callback used to start the database a short timer after startup
+  if (!strcmp(aTopic, NS_TIMER_CALLBACK_TOPIC)) {
+    nsCOMPtr<nsITimer> timer = do_QueryInterface(aSubject);
+    if (!timer) {
+      return NS_ERROR_UNEXPECTED;
+    }
+
+    if (timer == mDBThreadStartDelayTimer) {
+      mDBThreadStartDelayTimer = nullptr;
+
+      DOMStorageDBBridge* db = DOMStorageCache::StartDatabase();
+      NS_ENSURE_TRUE(db, NS_ERROR_FAILURE);
+    }
+
+    return NS_OK;
+  }
+
+  // Clear everything, caches + database
+  if (!strcmp(aTopic, "cookie-changed")) {
+    if (!NS_LITERAL_STRING("cleared").Equals(aData)) {
+      return NS_OK;
+    }
+
+    DOMStorageDBBridge* db = DOMStorageCache::StartDatabase();
+    NS_ENSURE_TRUE(db, NS_ERROR_FAILURE);
+
+    db->AsyncClearAll();
+
+    Notify("cookie-cleared");
+
+    return NS_OK;
+  }
+
+  // Clear from caches everything that has been stored
+  // while in session-only mode
+  if (!strcmp(aTopic, "perm-changed")) {
+    // Check for cookie permission change
+    nsCOMPtr<nsIPermission> perm(do_QueryInterface(aSubject));
+    if (!perm) {
+      return NS_OK;
+    }
+
+    nsAutoCString type;
+    perm->GetType(type);
+    if (type != NS_LITERAL_CSTRING("cookie")) {
+      return NS_OK;
+    }
+
+    uint32_t cap = 0;
+    perm->GetCapability(&cap);
+    if (!(cap & nsICookiePermission::ACCESS_SESSION) ||
+        !NS_LITERAL_STRING("deleted").Equals(nsDependentString(aData))) {
+      return NS_OK;
+    }
+
+    nsAutoCString host;
+    perm->GetHost(host);
+    if (host.IsEmpty()) {
+      return NS_OK;
+    }
+
+    nsAutoCString scope;
+    rv = CreateReversedDomain(host, scope);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    Notify("session-only-cleared", scope);
+
+    return NS_OK;
+  }
+
+  // Clear everything (including so and pb data) from caches and database
+  // for the gived domain and subdomains.
+  if (!strcmp(aTopic, "browser:purge-domain-data")) {
+    // Convert the domain name to the ACE format
+    nsAutoCString aceDomain;
+    nsCOMPtr<nsIIDNService> converter = do_GetService(NS_IDNSERVICE_CONTRACTID);
+    if (converter) {
+      rv = converter->ConvertUTF8toACE(NS_ConvertUTF16toUTF8(aData), aceDomain);
+      NS_ENSURE_SUCCESS(rv, rv);
+    } else {
+      // In case the IDN service is not available, this is the best we can come up with!
+      NS_EscapeURL(NS_ConvertUTF16toUTF8(aData),
+                   esc_OnlyNonASCII | esc_AlwaysCopy,
+                   aceDomain);
+    }
+
+    nsAutoCString scopePrefix;
+    rv = CreateReversedDomain(aceDomain, scopePrefix);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    DOMStorageDBBridge* db = DOMStorageCache::StartDatabase();
+    NS_ENSURE_TRUE(db, NS_ERROR_FAILURE);
+
+    db->AsyncClearMatchingScope(scopePrefix);
+
+    Notify("domain-data-cleared", scopePrefix);
+
+    return NS_OK;
+  }
+
+  // Clear all private-browsing caches
+  if (!strcmp(aTopic, "last-pb-context-exited")) {
+    Notify("private-browsing-data-cleared");
+
+    return NS_OK;
+  }
+
+  // Clear data beloging to an app.
+  if (!strcmp(aTopic, "webapps-clear-data")) {
+    nsCOMPtr<mozIApplicationClearPrivateDataParams> params =
+      do_QueryInterface(aSubject);
+    if (!params) {
+      NS_ERROR("'webapps-clear-data' notification's subject should be a mozIApplicationClearPrivateDataParams");
+      return NS_ERROR_UNEXPECTED;
+    }
+
+    uint32_t appId;
+    bool browserOnly;
+
+    rv = params->GetAppId(&appId);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = params->GetBrowserOnly(&browserOnly);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    MOZ_ASSERT(appId != nsIScriptSecurityManager::UNKNOWN_APP_ID);
+
+    DOMStorageDBBridge* db = DOMStorageCache::StartDatabase();
+    NS_ENSURE_TRUE(db, NS_ERROR_FAILURE);
+
+    nsAutoCString scope;
+    scope.AppendInt(appId);
+    scope.Append(NS_LITERAL_CSTRING(":t:"));
+    db->AsyncClearMatchingScope(scope);
+    Notify("app-data-cleared", scope);
+
+    if (!browserOnly) {
+      scope.Truncate();
+      scope.AppendInt(appId);
+      scope.Append(NS_LITERAL_CSTRING(":f:"));
+      db->AsyncClearMatchingScope(scope);
+      Notify("app-data-cleared", scope);
+    }
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, "profile-after-change")) {
+    Notify("profile-change");
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, "profile-before-change") ||
+      !strcmp(aTopic, "xpcom-shutdown")) {
+    rv = DOMStorageCache::StopDatabase();
+    if (NS_FAILED(rv)) {
+      NS_WARNING("Error while stopping DOMStorage DB background thread");
+    }
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, "disk-space-watcher")) {
+    if (NS_LITERAL_STRING("full").Equals(aData)) {
+      Notify("low-disk-space");
+    } else if (NS_LITERAL_STRING("free").Equals(aData)) {
+      Notify("no-low-disk-space");
+    }
+
+    return NS_OK;
+  }
+
+#ifdef DOM_STORAGE_TESTS
+  if (!strcmp(aTopic, "domstorage-test-flush-force")) {
+    DOMStorageDBBridge* db = DOMStorageCache::GetDatabase();
+    if (db) {
+      db->AsyncFlush();
+    }
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, "domstorage-test-flushed")) {
+    // Only used to propagate to IPC children
+    Notify("test-flushed");
+
+    return NS_OK;
+  }
+
+  if (!strcmp(aTopic, "domstorage-test-reload")) {
+    Notify("test-reload");
+
+    return NS_OK;
+  }
+#endif
+
+  NS_ERROR("Unexpected topic");
+  return NS_ERROR_UNEXPECTED;
+}
+
+} // ::dom
+} // ::mozilla