1 files changed, 109 insertions, 0 deletions
diff --git a/xpcom/ds/nsIObserverService.idl b/xpcom/ds/nsIObserverService.idl
new file mode 100644
index 0000000000..5ca51d5d44
--- /dev/null
+++ b/xpcom/ds/nsIObserverService.idl
@@ -0,0 +1,109 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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 "nsISupports.idl"
+
+interface nsIObserver;
+interface nsISimpleEnumerator;
+
+/**
+ * nsIObserverService
+ *
+ * Service allows a client listener (nsIObserver) to register and unregister for
+ * notifications of specific string referenced topic. Service also provides a
+ * way to notify registered listeners and a way to enumerate registered client
+ * listeners.
+ */
+
+[scriptable, builtinclass, uuid(D07F5192-E3D1-11d2-8ACD-00105A1B8860)]
+interface nsIObserverService : nsISupports
+{
+
+    /**
+     * AddObserver
+     *
+     * Registers a given listener for a notifications regarding the specified
+     * topic.
+     *
+     * @param anObserve : The interface pointer which will receive notifications.
+     * @param aTopic    : The notification topic or subject.
+     * @param ownsWeak  : If set to false, the nsIObserverService will hold a
+     *                    strong reference to |anObserver|.  If set to true and
+     *                    |anObserver| supports the nsIWeakReference interface,
+     *                    a weak reference will be held.  Otherwise an error will be
+     *                    returned.
+     */
+    void addObserver( in nsIObserver anObserver, in string aTopic,
+                      [optional] in boolean ownsWeak);
+
+    /**
+     * removeObserver
+     *
+     * Unregisters a given listener from notifications regarding the specified
+     * topic.
+     *
+     * @param anObserver : The interface pointer which will stop recieving
+     *                     notifications.
+     * @param aTopic     : The notification topic or subject.
+     */
+    void removeObserver( in nsIObserver anObserver, in string aTopic );
+
+    /**
+     * notifyObservers
+     *
+     * Notifies all registered listeners of the given topic.
+     * Must not be used with shutdown topics (will assert
+     * on the parent process).
+     *
+     * @param aSubject : Notification specific interface pointer.
+     * @param aTopic   : The notification topic or subject.
+     * @param someData : Notification specific wide string.
+     */
+    void notifyObservers( in nsISupports aSubject,
+                          in string aTopic,
+                          [optional] in wstring someData );
+
+    /**
+     * hasObservers
+     *
+     * Checks to see if there are registered listeners for the given topic.
+     *
+     * Implemented in "nsObserverService.cpp".
+     *
+     * @param aTopic   : The notification topic or subject.
+     * @param aFound : An out parameter; True if there are registered observers,
+     * False otherwise.
+     */
+    [noscript, notxpcom, nostdcall] boolean hasObservers(in string aTopic);
+
+    %{C++
+    /**
+     * notifyWhenScriptSafe
+     *
+     * Notifies all registered listeners of the given topic once it is safe to
+     * run script.
+     *
+     * Implemented in "nsObserverService.cpp".
+     *
+     * @param aSubject : Notification specific interface pointer.
+     * @param aTopic   : The notification topic or subject.
+     * @param someData : Notification specific wide string.
+     */
+    nsresult NotifyWhenScriptSafe(nsISupports* aSubject,
+                                  const char* aTopic,
+                                  const char16_t* aData = nullptr);
+    %}
+
+    /**
+     * enumerateObservers
+     *
+     * Returns an enumeration of all registered listeners.
+     *
+     * @param aTopic   : The notification topic or subject.
+     */
+    nsISimpleEnumerator enumerateObservers( in string aTopic );
+
+
+};