diff options
Diffstat (limited to 'lisp')
| -rw-r--r-- | lisp/net/dbus.el | 75 |
1 files changed, 58 insertions, 17 deletions
diff --git a/lisp/net/dbus.el b/lisp/net/dbus.el index 0c748e76fcf..3a5cf48b92f 100644 --- a/lisp/net/dbus.el +++ b/lisp/net/dbus.el @@ -445,8 +445,17 @@ object path SERVICE is registered at. INTERFACE is an interface offered by SERVICE. It must provide METHOD. HANDLER is a Lisp function, which is called when the corresponding -return message has arrived. If HANDLER is nil, no return message -will be expected. +return message has arrived. It uses the returned values from the METHOD +call as arguments. These are the same arguments which are returned when +`dbus-call-method' is invoked instead. If HANDLER is nil, no return +message will be expected. + +HANDLER can also be the cons cell `(HANDLER . ERROR-HANDLER)'. In this +case, ERROR-HANDLER will be called in case an error is returned from +D-Bus. It uses the returned D-Bus error as argument. + +Neither the return value of HANDLER nor the return value of +ERROR-HANDLER is used. If the parameter `:timeout' is given, the following integer TIMEOUT specifies the maximum number of milliseconds before the @@ -477,18 +486,37 @@ about type keywords, see Info node `(dbus)Type Conversion'. If HANDLER is a Lisp function, the function returns a key into the hash table `dbus-registered-objects-table'. The corresponding entry in the hash table is removed, when the return message arrives, -and HANDLER is called. +and HANDLER is called. Examples: -Example: +The return value of \"org.freedesktop.portal.Settings.ReadOne\" is a variant. \(dbus-call-method-asynchronously - :system \"org.freedesktop.Hal\" \"/org/freedesktop/Hal/devices/computer\" - \"org.freedesktop.Hal.Device\" \"GetPropertyString\" #\\='message - \"system.kernel.machine\") + :session \"org.freedesktop.portal.Desktop\" + \"/org/freedesktop/portal/desktop\" + \"org.freedesktop.portal.Settings\" \"ReadOne\" + \\='((lambda (msg) (message \"Method handler %s\" msg)) . + (lambda (err) (message \"Error handler %s\" err))) + \"org.freedesktop.appearance\" \"color-scheme\") + + -| Method handler (0) - -| i686 + => (:serial :session 4) - => (:serial :system 2)" +There does not exist a method \"org.freedesktop.portal.Settings.ReadTwo\". + +\(dbus-call-method-asynchronously + :session \"org.freedesktop.portal.Desktop\" + \"/org/freedesktop/portal/desktop\" + \"org.freedesktop.portal.Settings\" \"ReadTwo\" + \\='((lambda (msg) (message \"Method handler %s\" msg)) . + (lambda (err) (message \"Error handler %s\" err))) + \"org.freedesktop.appearance\" \"color-scheme\") + + -| Error handler + (dbus-error org.freedesktop.DBus.Error.UnknownMethod + No such method \"ReadTwo\") + + => (:serial :session 5)" (or (featurep 'dbusbind) (signal 'dbus-error (list "Emacs not compiled with dbus support"))) @@ -504,6 +532,7 @@ Example: (or (stringp method) (signal 'wrong-type-argument (list 'stringp method))) (or (null handler) (functionp handler) + (and (listp handler) (functionp (car handler)) (functionp (cdr handler))) (signal 'wrong-type-argument (list 'functionp handler))) (apply #'dbus-message-internal dbus-message-type-method-call @@ -1111,9 +1140,11 @@ INTERFACE and MEMBER denote the message which has been sent. When TYPE is `dbus-message-type-error', MEMBER is the error name. HANDLER is the function which has been registered for this -message. ARGS are the typed arguments as returned from the -message. They are passed to HANDLER without type information, -when it is called during event handling in `dbus-handle-event'. +message. It can also be a cons cell (HANDLER . ERROR-HANDLER). + +ARGS are the typed arguments as returned from the message. They are +passed to HANDLER without type information, when it is called during +event handling in `dbus-handle-event'. This function signals a `dbus-error' if the event is not well formed." @@ -1150,7 +1181,10 @@ formed." (or (= dbus-message-type-method-return (nth 2 event)) (stringp (nth 8 event))) ;; Handler. - (functionp (nth 9 event)) + (or (functionp (nth 9 event)) + (and (consp (nth 9 event)) + (functionp (car (nth 9 event))) + (functionp (cdr (nth 9 event))))) ;; Arguments. (listp (nthcdr 10 event))) (signal 'dbus-error (list "Not a valid D-Bus event" event)))) @@ -1207,10 +1241,17 @@ If the HANDLER returns a `dbus-error', it is propagated as return message." (setq result (dbus-ignore-errors (apply (nth 9 event) args))) ;; Error messages must be propagated. The error name is in ;; the member slot. - (when (= dbus-message-type-error (nth 2 event)) - (signal 'dbus-error (cons (nth 8 event) args))) - ;; Apply the handler. - (setq result (apply (nth 9 event) args)) + (let* ((handler (nth 9 event)) + (error-handler (if (functionp handler) #'signal + (prog1 (cdr handler) + (setq handler (car handler)))))) + (setq result + (if (= dbus-message-type-error (nth 2 event)) + (funcall + error-handler + (cons 'dbus-error (cons (nth 8 event) args))) + ;; Apply the handler. + (apply handler args)))) ;; Return an (error) message when it is a message call. (when (= dbus-message-type-method-call (nth 2 event)) (dbus-ignore-errors |