From 7c75524e72f5cc43f6dcb9a46b08108c3c6f4f71 Mon Sep 17 00:00:00 2001
From: Michael Albinus <albinus@detlef>
Date: Tue, 16 Mar 2010 00:27:31 +0100
Subject: [PATCH] * net/secrets.el (top): Register the D-Bus signals only when
 the service "org.freedesktop.secrets" can be pinged.  Provide subfeature
 'enabled.

---
 lisp/ChangeLog      |  6 +++++
 lisp/net/secrets.el | 57 ++++++++++++++++++++++++++++-----------------
 2 files changed, 42 insertions(+), 21 deletions(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index d80d987972a..54e427eeda5 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2010-03-15  Michael Albinus  <michael.albinus@gmx.de>
+
+	* net/secrets.el (top): Register the D-Bus signals only when the
+	service "org.freedesktop.secrets" can be pinged.  Provide
+	subfeature 'enabled.
+
 2010-03-14  Juri Linkov  <juri@jurta.org>
 
 	Add finder unknown keywords.
diff --git a/lisp/net/secrets.el b/lisp/net/secrets.el
index dbf3d03be0b..07062810b80 100644
--- a/lisp/net/secrets.el
+++ b/lisp/net/secrets.el
@@ -32,9 +32,14 @@
 
 ;; In order to activate this package, you must add the following code
 ;; into your .emacs:
-
+;;
 ;;   (require 'secrets)
 
+;; It can be checked afterwards, whether there is a daemon providing
+;; this interface:
+;;
+;;   (featurep 'secrets 'enabled)
+
 ;; The atomic objects to be managed by the Secret Service API are
 ;; secret items, which are something an application wishes to store
 ;; securely.  A good example is a password that an application needs
@@ -383,14 +388,6 @@ returned, and it will be stored in `secrets-session-path'."
     (setq secrets-collection-paths
 	  (delete (car args) secrets-collection-paths)))))
 
-(dbus-register-signal
- :session secrets-service secrets-path
- secrets-interface-service "CollectionCreated" 'secrets-collection-handler)
-
-(dbus-register-signal
- :session secrets-service secrets-path
- secrets-interface-service "CollectionDeleted" 'secrets-collection-handler)
-
 (defun secrets-get-collections ()
   "Return the object paths of all available collections."
   (setq secrets-collection-paths
@@ -667,20 +664,38 @@ If there is no such item, or the item doesn't own this attribute, return nil."
 	:session secrets-service item-path
 	secrets-interface-item "Delete")))))
 
-;; We must reset all variables, when there is a new instance of the
-;; "org.freedesktop.secrets" service.
+(if (dbus-ping :session secrets-service 100)
+
+    (progn
+      ;; We must reset all variables, when there is a new instance of
+      ;; the "org.freedesktop.secrets" service.
+      (dbus-register-signal
+       :session dbus-service-dbus dbus-path-dbus
+       dbus-interface-dbus "NameOwnerChanged"
+       (lambda (&rest args)
+	 (when secrets-debug (message "Secret Service has changed: %S" args))
+	 (setq secrets-session-path secrets-empty-path
+	       secrets-prompt-signal nil
+	       secrets-collection-paths nil))
+       secrets-service)
+
+      ;; We want to refresh our cache, when there is a change in
+      ;; collections.
+      (dbus-register-signal
+       :session secrets-service secrets-path
+       secrets-interface-service "CollectionCreated"
+       'secrets-collection-handler)
+
+      (dbus-register-signal
+       :session secrets-service secrets-path
+       secrets-interface-service "CollectionDeleted"
+       'secrets-collection-handler)
 
-(dbus-register-signal
- :session dbus-service-dbus dbus-path-dbus
- dbus-interface-dbus "NameOwnerChanged"
- (lambda (&rest args)
-   (when secrets-debug (message "Secret Service has changed: %S" args))
-   (setq secrets-session-path secrets-empty-path
-	 secrets-prompt-signal nil
-	 secrets-collection-paths nil))
- secrets-service)
+      ;; We shall inform, whether the secret service is enabled on
+      ;; this machine.
+      (provide 'secrets '(enabled)))
 
-(provide 'secrets)
+  (provide 'secrets))
 
 ;;; TODO:
 
-- 
2.39.2