Bug 786419 - Part 1 - Provide way to "set network offline" per app r=jduell

Author: valenting

netwerk/base/public/nsIIOService.idl

@@ -88,6 +88,24 @@ interface nsIIOService : nsISupports
      */
     attribute boolean offline;
 
+    /**
+     * Set whether network appears to be offline for network connections from
+     * a given appID.
+     *
+     * Calling this function may fire the "network:app-offline-status-changed"
+     * notification, which is also sent to child processes containing this appId.
+     * 'state' must one of nsIAppOfflineInfo::{ONLINE|OFFLINE|WIFI_ONLY}.
+     */
+    void setAppOffline(in uint32_t appId, in long state);
+
+    /**
+     * Returns true if given appId is currently not allowed to make network
+     * connections. It will return true if the app is in the wifi-only state
+     * and we are currently on a 3G connection.
+     */
+    boolean isAppOffline(in uint32_t appId);
+
+
     /**
      * Checks if a port number is banned. This involves consulting a list of
      * unsafe ports, corresponding to network services that may be easily
@@ -117,6 +135,18 @@ interface nsIIOService : nsISupports
     ACString extractScheme(in AUTF8String urlString);
 };
 
+[scriptable, uuid(4ac296a0-ca1b-44f4-8787-117a88cb70fb)]
+interface nsIAppOfflineInfo : nsISupports
+{
+    readonly attribute unsigned long appId;
+
+    const long ONLINE = 1;
+    const long OFFLINE = 2;
+    const long WIFI_ONLY = 3;
+
+    readonly attribute long mode;
+};
+
 %{C++
 /**
  * We send notifications through nsIObserverService with topic
@@ -136,4 +166,10 @@ interface nsIIOService : nsISupports
 #define NS_IOSERVICE_OFFLINE_STATUS_TOPIC "network:offline-status-changed"
 #define NS_IOSERVICE_OFFLINE              "offline"
 #define NS_IOSERVICE_ONLINE               "online"
+
+/**
+ * When network:app-offline-status-changed is fired,
+ * the 'Subject' argument is a nsIOfflineAppInfo.
+ */
+#define NS_IOSERVICE_APP_OFFLINE_STATUS_TOPIC "network:app-offline-status-changed"
 %}

netwerk/base/src/OfflineObserver.cpp

@@ -0,0 +1,124 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set sw=2 ts=8 et 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 "OfflineObserver.h"
+#include "nsNetUtil.h"
+#include "nsIOService.h"
+#include "mozilla/net/NeckoCommon.h"
+#include "nsIObserverService.h"
+#include "nsThreadUtils.h"
+namespace mozilla {
+namespace net {
+
+NS_IMPL_ISUPPORTS(OfflineObserver, nsIObserver)
+
+void
+OfflineObserver::RegisterOfflineObserver()
+{
+  if (NS_IsMainThread()) {
+    RegisterOfflineObserverMainThread();
+  } else {
+    nsRefPtr<nsIRunnable> event =
+      NS_NewRunnableMethod(this, &OfflineObserver::RegisterOfflineObserverMainThread);
+    NS_DispatchToMainThread(event);
+  }
+}
+
+void
+OfflineObserver::RemoveOfflineObserver()
+{
+  if (NS_IsMainThread()) {
+    RemoveOfflineObserverMainThread();
+  } else {
+    nsRefPtr<nsIRunnable> event =
+      NS_NewRunnableMethod(this, &OfflineObserver::RemoveOfflineObserverMainThread);
+    NS_DispatchToMainThread(event);
+  }
+}
+
+void
+OfflineObserver::RegisterOfflineObserverMainThread()
+{
+  nsCOMPtr<nsIObserverService> observerService =
+    mozilla::services::GetObserverService();
+  if (!observerService) {
+    return;
+  }
+  nsresult rv = observerService->AddObserver(this,
+    NS_IOSERVICE_APP_OFFLINE_STATUS_TOPIC, false);
+  if (NS_FAILED(rv)) {
+    NS_WARNING("Failed to register observer");
+  }
+}
+
+void
+OfflineObserver::RemoveOfflineObserverMainThread()
+{
+  nsCOMPtr<nsIObserverService> observerService =
+    mozilla::services::GetObserverService();
+  if (observerService) {
+    observerService->RemoveObserver(this, NS_IOSERVICE_APP_OFFLINE_STATUS_TOPIC);
+  }
+}
+
+OfflineObserver::OfflineObserver(DisconnectableParent * parent)
+{
+  mParent = parent;
+  RegisterOfflineObserver();
+}
+
+void
+OfflineObserver::RemoveObserver()
+{
+  RemoveOfflineObserver();
+  mParent = nullptr;
+}
+
+NS_IMETHODIMP
+OfflineObserver::Observe(nsISupports *aSubject,
+                         const char *aTopic,
+                         const char16_t *aData)
+{
+  if (mParent &&
+      !strcmp(aTopic, NS_IOSERVICE_APP_OFFLINE_STATUS_TOPIC)) {
+    mParent->OfflineNotification(aSubject);
+  }
+  return NS_OK;
+}
+
+uint32_t
+DisconnectableParent::GetAppId()
+{
+  return NECKO_UNKNOWN_APP_ID;
+}
+
+nsresult
+DisconnectableParent::OfflineNotification(nsISupports *aSubject)
+{
+  nsCOMPtr<nsIAppOfflineInfo> info(do_QueryInterface(aSubject));
+  if (!info) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+
+  uint32_t targetAppId = NECKO_UNKNOWN_APP_ID;
+  info->GetAppId(&targetAppId);
+
+  // Obtain App ID
+  uint32_t appId = GetAppId();
+  if (appId != targetAppId) {
+    return NS_OK;
+  }
+
+  // If the app is offline, close the socket
+  if (NS_IsAppOffline(appId)) {
+    OfflineDisconnect();
+  }
+
+  return NS_OK;
+}
+
+} // net namespace
+} // mozilla namespace

netwerk/base/src/OfflineObserver.h

@@ -0,0 +1,73 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set sw=2 ts=8 et 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/. */
+
+#ifndef nsOfflineObserver_h__
+#define nsOfflineObserver_h__
+
+#include "nsIObserver.h"
+
+namespace mozilla {
+namespace net {
+
+/**
+ * Parents should extend this class and have a nsRefPtr<OfflineObserver> member.
+ * The constructor should initialize the member to new OfflineObserver(this)
+ * and the destructor should call RemoveObserver on the member.
+ *
+ * GetAppId and OfflineDisconnect are called from the default implementation
+ * of OfflineNotification. These should be overridden by classes that don't
+ * provide an implementation of OfflineNotification.
+ */
+class DisconnectableParent
+{
+public:
+  // This is called on the main thread, by the OfflineObserver.
+  // aSubject is of type nsAppOfflineInfo and contains appId and offline mode.
+  virtual nsresult OfflineNotification(nsISupports *aSubject);
+
+  // GetAppId returns the appId for the app associated with the parent
+  virtual uint32_t GetAppId();
+
+  // OfflineDisconnect cancels all existing connections in the parent when
+  // the app becomes offline.
+  virtual void     OfflineDisconnect() { }
+};
+
+/**
+ * This class observes the "network:app-offline-status-changed" topic and calls
+ * OfflineNotification on the DisconnectableParent with the subject.
+ */
+class OfflineObserver
+  : public nsIObserver
+{
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+public:
+  // A nsRefPtr to this object should be kept by the disconnectable parent.
+
+  OfflineObserver(DisconnectableParent * parent);
+  // This method needs to be called in the destructor of the parent
+  // It removes the observer from the nsObserverService list, and it clears
+  // the pointer it holds to the disconnectable parent.
+  void RemoveObserver();
+private:
+
+  // These methods are called to register and unregister the observer.
+  // If they are called on the main thread they register the observer right
+  // away, otherwise they dispatch and event to the main thread
+  void RegisterOfflineObserver();
+  void RemoveOfflineObserver();
+  void RegisterOfflineObserverMainThread();
+  void RemoveOfflineObserverMainThread();
+private:
+  virtual ~OfflineObserver() { }
+  DisconnectableParent * mParent;
+};
+
+} // net namespace
+} // mozilla namespace
+
+#endif // nsOfflineObserver_h__

netwerk/base/src/moz.build

@@ -17,6 +17,7 @@ EXPORTS.mozilla.net += [
     'ChannelDiverterParent.h',
     'Dashboard.h',
     'DashboardTypes.h',
+    'OfflineObserver.h',
 ]
 
 UNIFIED_SOURCES += [
@@ -85,6 +86,7 @@ SOURCES += [
     'nsAsyncRedirectVerifyHelper.cpp',
     'nsSocketTransport2.cpp',
     'nsSocketTransportService2.cpp',
+    'OfflineObserver.cpp',
 ]
 
 if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'windows':