mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-15 09:47:20 +00:00
835 lines
32 KiB
EmacsLisp
835 lines
32 KiB
EmacsLisp
;;; dbus.el --- Elisp bindings for D-Bus.
|
||
|
||
;; Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc.
|
||
|
||
;; Author: Michael Albinus <michael.albinus@gmx.de>
|
||
;; Keywords: comm, hardware
|
||
|
||
;; This file is part of GNU Emacs.
|
||
|
||
;; GNU Emacs is free software: you can redistribute it and/or modify
|
||
;; it under the terms of the GNU General Public License as published by
|
||
;; the Free Software Foundation, either version 3 of the License, or
|
||
;; (at your option) any later version.
|
||
|
||
;; GNU Emacs is distributed in the hope that it will be useful,
|
||
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
;; GNU General Public License for more details.
|
||
|
||
;; You should have received a copy of the GNU General Public License
|
||
;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
|
||
|
||
;;; Commentary:
|
||
|
||
;; This package provides language bindings for the D-Bus API. D-Bus
|
||
;; is a message bus system, a simple way for applications to talk to
|
||
;; one another. See <http://dbus.freedesktop.org/> for details.
|
||
|
||
;; Low-level language bindings are implemented in src/dbusbind.c.
|
||
|
||
;;; Code:
|
||
|
||
;; D-Bus support in the Emacs core can be disabled with configuration
|
||
;; option "--without-dbus". Declare used subroutines and variables.
|
||
(declare-function dbus-call-method "dbusbind.c")
|
||
(declare-function dbus-call-method-asynchronously "dbusbind.c")
|
||
(declare-function dbus-method-return-internal "dbusbind.c")
|
||
(declare-function dbus-method-error-internal "dbusbind.c")
|
||
(declare-function dbus-register-signal "dbusbind.c")
|
||
(defvar dbus-debug)
|
||
(defvar dbus-registered-functions-table)
|
||
|
||
;; Pacify byte compiler.
|
||
(eval-when-compile
|
||
(require 'cl))
|
||
|
||
(require 'xml)
|
||
|
||
(defconst dbus-service-dbus "org.freedesktop.DBus"
|
||
"The bus name used to talk to the bus itself.")
|
||
|
||
(defconst dbus-path-dbus "/org/freedesktop/DBus"
|
||
"The object path used to talk to the bus itself.")
|
||
|
||
(defconst dbus-interface-dbus "org.freedesktop.DBus"
|
||
"The interface exported by the object with `dbus-service-dbus' and `dbus-path-dbus'.")
|
||
|
||
(defconst dbus-interface-peer (concat dbus-interface-dbus ".Peer")
|
||
"The interface for peer objects.")
|
||
|
||
(defconst dbus-interface-introspectable
|
||
(concat dbus-interface-dbus ".Introspectable")
|
||
"The interface supported by introspectable objects.")
|
||
|
||
(defconst dbus-interface-properties (concat dbus-interface-dbus ".Properties")
|
||
"The interface for property objects.")
|
||
|
||
(defconst dbus-service-emacs "org.gnu.Emacs"
|
||
"The well known service name of Emacs.")
|
||
|
||
(defconst dbus-path-emacs "/org/gnu/Emacs"
|
||
"The object path head used by Emacs.")
|
||
|
||
(defconst dbus-message-type-invalid 0
|
||
"This value is never a valid message type.")
|
||
|
||
(defconst dbus-message-type-method-call 1
|
||
"Message type of a method call message.")
|
||
|
||
(defconst dbus-message-type-method-return 2
|
||
"Message type of a method return message.")
|
||
|
||
(defconst dbus-message-type-error 3
|
||
"Message type of an error reply message.")
|
||
|
||
(defconst dbus-message-type-signal 4
|
||
"Message type of a signal message.")
|
||
|
||
(defmacro dbus-ignore-errors (&rest body)
|
||
"Execute BODY; signal D-Bus error when `dbus-debug' is non-nil.
|
||
Otherwise, return result of last form in BODY, or all other errors."
|
||
`(condition-case err
|
||
(progn ,@body)
|
||
(dbus-error (when dbus-debug (signal (car err) (cdr err))))))
|
||
|
||
(put 'dbus-ignore-errors 'lisp-indent-function 0)
|
||
(put 'dbus-ignore-errors 'edebug-form-spec '(form body))
|
||
(font-lock-add-keywords 'emacs-lisp-mode '("\\<dbus-ignore-errors\\>"))
|
||
|
||
(defvar dbus-event-error-hooks nil
|
||
"Functions to be called when a D-Bus error happens in the event handler.
|
||
Every function must accept two arguments, the event and the error variable
|
||
catched in `condition-case' by `dbus-error'.")
|
||
|
||
|
||
;;; Hash table of registered functions.
|
||
|
||
;; We create it here. So we have a simple test in dbusbind.c, whether
|
||
;; the Lisp code has been loaded.
|
||
(setq dbus-registered-functions-table (make-hash-table :test 'equal))
|
||
|
||
(defvar dbus-return-values-table (make-hash-table :test 'equal)
|
||
"Hash table for temporary storing arguments of reply messages.
|
||
A key in this hash table is a list (BUS SERIAL). BUS is either the
|
||
symbol `:system' or the symbol `:session'. SERIAL is the serial number
|
||
of the reply message. See `dbus-call-method-non-blocking-handler' and
|
||
`dbus-call-method-non-blocking'.")
|
||
|
||
(defun dbus-list-hash-table ()
|
||
"Returns all registered member registrations to D-Bus.
|
||
The return value is a list, with elements of kind (KEY . VALUE).
|
||
See `dbus-registered-functions-table' for a description of the
|
||
hash table."
|
||
(let (result)
|
||
(maphash
|
||
'(lambda (key value) (add-to-list 'result (cons key value) 'append))
|
||
dbus-registered-functions-table)
|
||
result))
|
||
|
||
(defun dbus-unregister-object (object)
|
||
"Unregister OBJECT from D-Bus.
|
||
OBJECT must be the result of a preceding `dbus-register-method'
|
||
or `dbus-register-signal' call. It returns `t' if OBJECT has
|
||
been unregistered, `nil' otherwise."
|
||
;; Check parameter.
|
||
(unless (and (consp object) (not (null (car object))) (consp (cdr object)))
|
||
(signal 'wrong-type-argument (list 'D-Bus object)))
|
||
|
||
;; Find the corresponding entry in the hash table.
|
||
(let* ((key (car object))
|
||
(value (gethash key dbus-registered-functions-table)))
|
||
;; Loop over the registered functions.
|
||
(while (consp value)
|
||
;; (car value) has the structure (UNAME SERVICE PATH HANDLER).
|
||
;; (cdr object) has the structure ((SERVICE PATH HANDLER) ...).
|
||
(if (not (equal (cdr (car value)) (car (cdr object))))
|
||
(setq value (cdr value))
|
||
;; Compute new hash value. If it is empty, remove it from
|
||
;; hash table.
|
||
(unless
|
||
(puthash
|
||
key
|
||
(delete (car value) (gethash key dbus-registered-functions-table))
|
||
dbus-registered-functions-table)
|
||
(remhash key dbus-registered-functions-table))
|
||
(setq value t)))
|
||
value))
|
||
|
||
(defun dbus-call-method-non-blocking-handler (&rest args)
|
||
"Handler for reply messages of asynchronous D-Bus message calls.
|
||
It calls the function stored in `dbus-registered-functions-table'.
|
||
The result will be made available in `dbus-return-values-table'."
|
||
(puthash (list (dbus-event-bus-name last-input-event)
|
||
(dbus-event-serial-number last-input-event))
|
||
(if (= (length args) 1) (car args) args)
|
||
dbus-return-values-table))
|
||
|
||
(defun dbus-call-method-non-blocking
|
||
(bus service path interface method &rest args)
|
||
"Call METHOD on the D-Bus BUS, but don't block the event queue.
|
||
This is necessary for communicating to registered D-Bus methods,
|
||
which are running in the same Emacs process.
|
||
|
||
The arguments are the same as in `dbus-call-method'.
|
||
|
||
usage: (dbus-call-method-non-blocking
|
||
BUS SERVICE PATH INTERFACE METHOD
|
||
&optional :timeout TIMEOUT &rest ARGS)"
|
||
|
||
(let ((key
|
||
(apply
|
||
'dbus-call-method-asynchronously
|
||
bus service path interface method
|
||
'dbus-call-method-non-blocking-handler args)))
|
||
;; Wait until `dbus-call-method-non-blocking-handler' has put the
|
||
;; result into `dbus-return-values-table'.
|
||
(while (not (gethash key dbus-return-values-table nil))
|
||
(read-event nil nil 0.1))
|
||
|
||
;; Cleanup `dbus-return-values-table'. Return the result.
|
||
(prog1
|
||
(gethash key dbus-return-values-table nil)
|
||
(remhash key dbus-return-values-table))))
|
||
|
||
(defun dbus-name-owner-changed-handler (&rest args)
|
||
"Reapplies all member registrations to D-Bus.
|
||
This handler is applied when a \"NameOwnerChanged\" signal has
|
||
arrived. SERVICE is the object name for which the name owner has
|
||
been changed. OLD-OWNER is the previous owner of SERVICE, or the
|
||
empty string if SERVICE was not owned yet. NEW-OWNER is the new
|
||
owner of SERVICE, or the empty string if SERVICE looses any name owner.
|
||
|
||
usage: (dbus-name-owner-changed-handler service old-owner new-owner)"
|
||
(save-match-data
|
||
;; Check the arguments. We should silently ignore it when they
|
||
;; are wrong.
|
||
(if (and (= (length args) 3)
|
||
(stringp (car args))
|
||
(stringp (cadr args))
|
||
(stringp (caddr args)))
|
||
(let ((service (car args))
|
||
(old-owner (cadr args))
|
||
(new-owner (caddr args)))
|
||
;; Check whether SERVICE is a known name.
|
||
(when (not (string-match "^:" service))
|
||
(maphash
|
||
'(lambda (key value)
|
||
(dolist (elt value)
|
||
;; key has the structure (BUS INTERFACE MEMBER).
|
||
;; elt has the structure (UNAME SERVICE PATH HANDLER).
|
||
(when (string-equal old-owner (car elt))
|
||
;; Remove old key, and add new entry with changed name.
|
||
(dbus-unregister-object (list key (cdr elt)))
|
||
;; Maybe we could arrange the lists a little bit better
|
||
;; that we don't need to extract every single element?
|
||
(dbus-register-signal
|
||
;; BUS SERVICE PATH
|
||
(nth 0 key) (nth 1 elt) (nth 2 elt)
|
||
;; INTERFACE MEMBER HANDLER
|
||
(nth 1 key) (nth 2 key) (nth 3 elt)))))
|
||
(copy-hash-table dbus-registered-functions-table))))
|
||
;; The error is reported only in debug mode.
|
||
(when dbus-debug
|
||
(signal
|
||
'dbus-error
|
||
(cons
|
||
(format "Wrong arguments of %s.NameOwnerChanged" dbus-interface-dbus)
|
||
args))))))
|
||
|
||
;; Register the handler.
|
||
(when nil ;ignore-errors
|
||
(dbus-register-signal
|
||
:system dbus-service-dbus dbus-path-dbus dbus-interface-dbus
|
||
"NameOwnerChanged" 'dbus-name-owner-changed-handler)
|
||
(dbus-register-signal
|
||
:session dbus-service-dbus dbus-path-dbus dbus-interface-dbus
|
||
"NameOwnerChanged" 'dbus-name-owner-changed-handler))
|
||
|
||
|
||
;;; D-Bus type conversion.
|
||
|
||
(defun dbus-string-to-byte-array (string)
|
||
"Transforms STRING to list (:array :byte c1 :byte c2 ...).
|
||
STRING shall be UTF8 coded."
|
||
(if (zerop (length string))
|
||
'(:array :signature "y")
|
||
(let (result)
|
||
(dolist (elt (string-to-list string) (append '(:array) result))
|
||
(setq result (append result (list :byte elt)))))))
|
||
|
||
(defun dbus-byte-array-to-string (byte-array)
|
||
"Transforms BYTE-ARRAY into UTF8 coded string.
|
||
BYTE-ARRAY must be a list of structure (c1 c2 ...)."
|
||
(apply 'string byte-array))
|
||
|
||
(defun dbus-escape-as-identifier (string)
|
||
"Escape an arbitrary STRING so it follows the rules for a C identifier.
|
||
The escaped string can be used as object path component, interface element
|
||
component, bus name component or member name in D-Bus.
|
||
|
||
The escaping consists of replacing all non-alphanumerics, and the
|
||
first character if it's a digit, with an underscore and two
|
||
lower-case hex digits:
|
||
|
||
\"0123abc_xyz\\x01\\xff\" -> \"_30123abc_5fxyz_01_ff\"
|
||
|
||
i.e. similar to URI encoding, but with \"_\" taking the role of \"%\",
|
||
and a smaller allowed set. As a special case, \"\" is escaped to
|
||
\"_\".
|
||
|
||
Returns the escaped string. Algorithm taken from
|
||
telepathy-glib's `tp-escape-as-identifier'."
|
||
(if (zerop (length string))
|
||
"_"
|
||
(replace-regexp-in-string
|
||
"^[0-9]\\|[^A-Za-z0-9]"
|
||
(lambda (x) (format "_%2x" (aref x 0)))
|
||
string)))
|
||
|
||
(defun dbus-unescape-from-identifier (string)
|
||
"Retrieve the original string from the encoded STRING.
|
||
STRING must have been coded with `dbus-escape-as-identifier'"
|
||
(if (string-equal string "_")
|
||
""
|
||
(replace-regexp-in-string
|
||
"_.."
|
||
(lambda (x) (format "%c" (string-to-number (substring x 1) 16)))
|
||
string)))
|
||
|
||
|
||
;;; D-Bus events.
|
||
|
||
(defun dbus-check-event (event)
|
||
"Checks whether EVENT is a well formed D-Bus event.
|
||
EVENT is a list which starts with symbol `dbus-event':
|
||
|
||
(dbus-event BUS TYPE SERIAL SERVICE PATH INTERFACE MEMBER HANDLER &rest ARGS)
|
||
|
||
BUS identifies the D-Bus the message is coming from. It is
|
||
either the symbol `:system' or the symbol `:session'. TYPE is
|
||
the D-Bus message type which has caused the event, SERIAL is the
|
||
serial number of the received D-Bus message. SERVICE and PATH
|
||
are the unique name and the object path of the D-Bus object
|
||
emitting the message. INTERFACE and MEMBER denote the message
|
||
which has been sent. HANDLER is the function which has been
|
||
registered for this message. ARGS are the arguments passed to
|
||
HANDLER, when it is called during event handling in
|
||
`dbus-handle-event'.
|
||
|
||
This function raises a `dbus-error' signal in case the event is
|
||
not well formed."
|
||
(when dbus-debug (message "DBus-Event %s" event))
|
||
(unless (and (listp event)
|
||
(eq (car event) 'dbus-event)
|
||
;; Bus symbol.
|
||
(symbolp (nth 1 event))
|
||
;; Type.
|
||
(and (natnump (nth 2 event))
|
||
(< dbus-message-type-invalid (nth 2 event)))
|
||
;; Serial.
|
||
(natnump (nth 3 event))
|
||
;; Service.
|
||
(or (= dbus-message-type-method-return (nth 2 event))
|
||
(= dbus-message-type-error (nth 2 event))
|
||
(stringp (nth 4 event)))
|
||
;; Object path.
|
||
(or (= dbus-message-type-method-return (nth 2 event))
|
||
(= dbus-message-type-error (nth 2 event))
|
||
(stringp (nth 5 event)))
|
||
;; Interface.
|
||
(or (= dbus-message-type-method-return (nth 2 event))
|
||
(= dbus-message-type-error (nth 2 event))
|
||
(stringp (nth 6 event)))
|
||
;; Member.
|
||
(or (= dbus-message-type-method-return (nth 2 event))
|
||
(= dbus-message-type-error (nth 2 event))
|
||
(stringp (nth 7 event)))
|
||
;; Handler.
|
||
(functionp (nth 8 event)))
|
||
(signal 'dbus-error (list "Not a valid D-Bus event" event))))
|
||
|
||
;;;###autoload
|
||
(defun dbus-handle-event (event)
|
||
"Handle events from the D-Bus.
|
||
EVENT is a D-Bus event, see `dbus-check-event'. HANDLER, being
|
||
part of the event, is called with arguments ARGS.
|
||
If the HANDLER returns an `dbus-error', it is propagated as return message."
|
||
(interactive "e")
|
||
(condition-case err
|
||
(let (result)
|
||
;; We ignore not well-formed events.
|
||
(dbus-check-event event)
|
||
;; Error messages must be propagated.
|
||
(when (= dbus-message-type-error (nth 2 event))
|
||
(signal 'dbus-error (nthcdr 9 event)))
|
||
;; Apply the handler.
|
||
(setq result (apply (nth 8 event) (nthcdr 9 event)))
|
||
;; Return a message when it is a message call.
|
||
(when (= dbus-message-type-method-call (nth 2 event))
|
||
(dbus-ignore-errors
|
||
(apply 'dbus-method-return-internal
|
||
(nth 1 event) (nth 3 event) (nth 4 event)
|
||
(if (consp result) result (list result))))))
|
||
;; Error handling.
|
||
(dbus-error
|
||
;; Return an error message when it is a message call.
|
||
(when (= dbus-message-type-method-call (nth 2 event))
|
||
(dbus-ignore-errors
|
||
(dbus-method-error-internal
|
||
(nth 1 event) (nth 3 event) (nth 4 event) (cadr err))))
|
||
;; Propagate D-Bus error messages.
|
||
(run-hook-with-args 'dbus-event-error-hooks event err)
|
||
(when (or dbus-debug (= dbus-message-type-error (nth 2 event)))
|
||
(signal (car err) (cdr err))))))
|
||
|
||
(defun dbus-event-bus-name (event)
|
||
"Return the bus name the event is coming from.
|
||
The result is either the symbol `:system' or the symbol `:session'.
|
||
EVENT is a D-Bus event, see `dbus-check-event'. This function
|
||
raises a `dbus-error' signal in case the event is not well
|
||
formed."
|
||
(dbus-check-event event)
|
||
(nth 1 event))
|
||
|
||
(defun dbus-event-message-type (event)
|
||
"Return the message type of the corresponding D-Bus message.
|
||
The result is a number. EVENT is a D-Bus event, see
|
||
`dbus-check-event'. This function raises a `dbus-error' signal
|
||
in case the event is not well formed."
|
||
(dbus-check-event event)
|
||
(nth 2 event))
|
||
|
||
(defun dbus-event-serial-number (event)
|
||
"Return the serial number of the corresponding D-Bus message.
|
||
The result is a number. The serial number is needed for
|
||
generating a reply message. EVENT is a D-Bus event, see
|
||
`dbus-check-event'. This function raises a `dbus-error' signal
|
||
in case the event is not well formed."
|
||
(dbus-check-event event)
|
||
(nth 3 event))
|
||
|
||
(defun dbus-event-service-name (event)
|
||
"Return the name of the D-Bus object the event is coming from.
|
||
The result is a string. EVENT is a D-Bus event, see `dbus-check-event'.
|
||
This function raises a `dbus-error' signal in case the event is
|
||
not well formed."
|
||
(dbus-check-event event)
|
||
(nth 4 event))
|
||
|
||
(defun dbus-event-path-name (event)
|
||
"Return the object path of the D-Bus object the event is coming from.
|
||
The result is a string. EVENT is a D-Bus event, see `dbus-check-event'.
|
||
This function raises a `dbus-error' signal in case the event is
|
||
not well formed."
|
||
(dbus-check-event event)
|
||
(nth 5 event))
|
||
|
||
(defun dbus-event-interface-name (event)
|
||
"Return the interface name of the D-Bus object the event is coming from.
|
||
The result is a string. EVENT is a D-Bus event, see `dbus-check-event'.
|
||
This function raises a `dbus-error' signal in case the event is
|
||
not well formed."
|
||
(dbus-check-event event)
|
||
(nth 6 event))
|
||
|
||
(defun dbus-event-member-name (event)
|
||
"Return the member name the event is coming from.
|
||
It is either a signal name or a method name. The result is is a
|
||
string. EVENT is a D-Bus event, see `dbus-check-event'. This
|
||
function raises a `dbus-error' signal in case the event is not
|
||
well formed."
|
||
(dbus-check-event event)
|
||
(nth 7 event))
|
||
|
||
|
||
;;; D-Bus registered names.
|
||
|
||
(defun dbus-list-activatable-names ()
|
||
"Return the D-Bus service names which can be activated as list.
|
||
The result is a list of strings, which is `nil' when there are no
|
||
activatable service names at all."
|
||
(dbus-ignore-errors
|
||
(dbus-call-method
|
||
:system dbus-service-dbus
|
||
dbus-path-dbus dbus-interface-dbus "ListActivatableNames")))
|
||
|
||
(defun dbus-list-names (bus)
|
||
"Return the service names registered at D-Bus BUS.
|
||
The result is a list of strings, which is `nil' when there are no
|
||
registered service names at all. Well known names are strings
|
||
like \"org.freedesktop.DBus\". Names starting with \":\" are
|
||
unique names for services."
|
||
(dbus-ignore-errors
|
||
(dbus-call-method
|
||
bus dbus-service-dbus dbus-path-dbus dbus-interface-dbus "ListNames")))
|
||
|
||
(defun dbus-list-known-names (bus)
|
||
"Retrieve all services which correspond to a known name in BUS.
|
||
A service has a known name if it doesn't start with \":\"."
|
||
(let (result)
|
||
(dolist (name (dbus-list-names bus) result)
|
||
(unless (string-equal ":" (substring name 0 1))
|
||
(add-to-list 'result name 'append)))))
|
||
|
||
(defun dbus-list-queued-owners (bus service)
|
||
"Return the unique names registered at D-Bus BUS and queued for SERVICE.
|
||
The result is a list of strings, or `nil' when there are no
|
||
queued name owners service names at all."
|
||
(dbus-ignore-errors
|
||
(dbus-call-method
|
||
bus dbus-service-dbus dbus-path-dbus
|
||
dbus-interface-dbus "ListQueuedOwners" service)))
|
||
|
||
(defun dbus-get-name-owner (bus service)
|
||
"Return the name owner of SERVICE registered at D-Bus BUS.
|
||
The result is either a string, or `nil' if there is no name owner."
|
||
(dbus-ignore-errors
|
||
(dbus-call-method
|
||
bus dbus-service-dbus dbus-path-dbus
|
||
dbus-interface-dbus "GetNameOwner" service)))
|
||
|
||
(defun dbus-ping (bus service)
|
||
"Check whether SERVICE is registered for D-Bus BUS."
|
||
;; "Ping" raises a D-Bus error if SERVICE does not exist.
|
||
;; Otherwise, it returns silently with `nil'.
|
||
(condition-case nil
|
||
(not
|
||
(dbus-call-method bus service dbus-path-dbus dbus-interface-peer "Ping"))
|
||
(dbus-error nil)))
|
||
|
||
|
||
;;; D-Bus introspection.
|
||
|
||
(defun dbus-introspect (bus service path)
|
||
"This function returns all interfaces and sub-nodes of SERVICE,
|
||
registered at object path PATH at bus BUS.
|
||
|
||
BUS must be either the symbol `:system' or the symbol `:session'.
|
||
SERVICE must be a known service name, and PATH must be a valid
|
||
object path. The last two parameters are strings. The result,
|
||
the introspection data, is a string in XML format."
|
||
;; We don't want to raise errors. `dbus-call-method-non-blocking'
|
||
;; is used, because the handler can be registered in our Emacs
|
||
;; instance; caller an callee would block each other.
|
||
(dbus-ignore-errors
|
||
(dbus-call-method-non-blocking
|
||
bus service path dbus-interface-introspectable "Introspect")))
|
||
|
||
(defun dbus-introspect-xml (bus service path)
|
||
"Return the introspection data of SERVICE in D-Bus BUS at object path PATH.
|
||
The data are a parsed list. The root object is a \"node\",
|
||
representing the object path PATH. The root object can contain
|
||
\"interface\" and further \"node\" objects."
|
||
;; We don't want to raise errors.
|
||
(xml-node-name
|
||
(ignore-errors
|
||
(with-temp-buffer
|
||
(insert (dbus-introspect bus service path))
|
||
(xml-parse-region (point-min) (point-max))))))
|
||
|
||
(defun dbus-introspect-get-attribute (object attribute)
|
||
"Return the ATTRIBUTE value of D-Bus introspection OBJECT.
|
||
ATTRIBUTE must be a string according to the attribute names in
|
||
the D-Bus specification."
|
||
(xml-get-attribute-or-nil object (intern attribute)))
|
||
|
||
(defun dbus-introspect-get-node-names (bus service path)
|
||
"Return all node names of SERVICE in D-Bus BUS at object path PATH.
|
||
It returns a list of strings. The node names stand for further
|
||
object paths of the D-Bus service."
|
||
(let ((object (dbus-introspect-xml bus service path))
|
||
result)
|
||
(dolist (elt (xml-get-children object 'node) result)
|
||
(add-to-list
|
||
'result (dbus-introspect-get-attribute elt "name") 'append))))
|
||
|
||
(defun dbus-introspect-get-all-nodes (bus service path)
|
||
"Return all node names of SERVICE in D-Bus BUS at object path PATH.
|
||
It returns a list of strings, which are further object paths of SERVICE."
|
||
(let ((result (list path)))
|
||
(dolist (elt
|
||
(dbus-introspect-get-node-names bus service path)
|
||
result)
|
||
(setq elt (expand-file-name elt path))
|
||
(setq result
|
||
(append result (dbus-introspect-get-all-nodes bus service elt))))))
|
||
|
||
(defun dbus-introspect-get-interface-names (bus service path)
|
||
"Return all interface names of SERVICE in D-Bus BUS at object path PATH.
|
||
It returns a list of strings.
|
||
|
||
There will be always the default interface
|
||
\"org.freedesktop.DBus.Introspectable\". Another default
|
||
interface is \"org.freedesktop.DBus.Properties\". If present,
|
||
\"interface\" objects can also have \"property\" objects as
|
||
children, beside \"method\" and \"signal\" objects."
|
||
(let ((object (dbus-introspect-xml bus service path))
|
||
result)
|
||
(dolist (elt (xml-get-children object 'interface) result)
|
||
(add-to-list
|
||
'result (dbus-introspect-get-attribute elt "name") 'append))))
|
||
|
||
(defun dbus-introspect-get-interface (bus service path interface)
|
||
"Return the INTERFACE of SERVICE in D-Bus BUS at object path PATH.
|
||
The return value is an XML object. INTERFACE must be a string,
|
||
element of the list returned by
|
||
`dbus-introspect-get-interface-names'. The resulting
|
||
\"interface\" object can contain \"method\", \"signal\",
|
||
\"property\" and \"annotation\" children."
|
||
(let ((elt (xml-get-children
|
||
(dbus-introspect-xml bus service path) 'interface)))
|
||
(while (and elt
|
||
(not (string-equal
|
||
interface
|
||
(dbus-introspect-get-attribute (car elt) "name"))))
|
||
(setq elt (cdr elt)))
|
||
(car elt)))
|
||
|
||
(defun dbus-introspect-get-method-names (bus service path interface)
|
||
"Return a list of strings of all method names of INTERFACE.
|
||
SERVICE is a service of D-Bus BUS at object path PATH."
|
||
(let ((object (dbus-introspect-get-interface bus service path interface))
|
||
result)
|
||
(dolist (elt (xml-get-children object 'method) result)
|
||
(add-to-list
|
||
'result (dbus-introspect-get-attribute elt "name") 'append))))
|
||
|
||
(defun dbus-introspect-get-method (bus service path interface method)
|
||
"Return method METHOD of interface INTERFACE as XML object.
|
||
It must be located at SERVICE in D-Bus BUS at object path PATH.
|
||
METHOD must be a string, element of the list returned by
|
||
`dbus-introspect-get-method-names'. The resulting \"method\"
|
||
object can contain \"arg\" and \"annotation\" children."
|
||
(let ((elt (xml-get-children
|
||
(dbus-introspect-get-interface bus service path interface)
|
||
'method)))
|
||
(while (and elt
|
||
(not (string-equal
|
||
method (dbus-introspect-get-attribute (car elt) "name"))))
|
||
(setq elt (cdr elt)))
|
||
(car elt)))
|
||
|
||
(defun dbus-introspect-get-signal-names (bus service path interface)
|
||
"Return a list of strings of all signal names of INTERFACE.
|
||
SERVICE is a service of D-Bus BUS at object path PATH."
|
||
(let ((object (dbus-introspect-get-interface bus service path interface))
|
||
result)
|
||
(dolist (elt (xml-get-children object 'signal) result)
|
||
(add-to-list
|
||
'result (dbus-introspect-get-attribute elt "name") 'append))))
|
||
|
||
(defun dbus-introspect-get-signal (bus service path interface signal)
|
||
"Return signal SIGNAL of interface INTERFACE as XML object.
|
||
It must be located at SERVICE in D-Bus BUS at object path PATH.
|
||
SIGNAL must be a string, element of the list returned by
|
||
`dbus-introspect-get-signal-names'. The resulting \"signal\"
|
||
object can contain \"arg\" and \"annotation\" children."
|
||
(let ((elt (xml-get-children
|
||
(dbus-introspect-get-interface bus service path interface)
|
||
'signal)))
|
||
(while (and elt
|
||
(not (string-equal
|
||
signal (dbus-introspect-get-attribute (car elt) "name"))))
|
||
(setq elt (cdr elt)))
|
||
(car elt)))
|
||
|
||
(defun dbus-introspect-get-property-names (bus service path interface)
|
||
"Return a list of strings of all property names of INTERFACE.
|
||
SERVICE is a service of D-Bus BUS at object path PATH."
|
||
(let ((object (dbus-introspect-get-interface bus service path interface))
|
||
result)
|
||
(dolist (elt (xml-get-children object 'property) result)
|
||
(add-to-list
|
||
'result (dbus-introspect-get-attribute elt "name") 'append))))
|
||
|
||
(defun dbus-introspect-get-property (bus service path interface property)
|
||
"This function returns PROPERTY of INTERFACE as XML object.
|
||
It must be located at SERVICE in D-Bus BUS at object path PATH.
|
||
PROPERTY must be a string, element of the list returned by
|
||
`dbus-introspect-get-property-names'. The resulting PROPERTY
|
||
object can contain \"annotation\" children."
|
||
(let ((elt (xml-get-children
|
||
(dbus-introspect-get-interface bus service path interface)
|
||
'property)))
|
||
(while (and elt
|
||
(not (string-equal
|
||
property
|
||
(dbus-introspect-get-attribute (car elt) "name"))))
|
||
(setq elt (cdr elt)))
|
||
(car elt)))
|
||
|
||
(defun dbus-introspect-get-annotation-names
|
||
(bus service path interface &optional name)
|
||
"Return all annotation names as list of strings.
|
||
If NAME is `nil', the annotations are children of INTERFACE,
|
||
otherwise NAME must be a \"method\", \"signal\", or \"property\"
|
||
object, where the annotations belong to."
|
||
(let ((object
|
||
(if name
|
||
(or (dbus-introspect-get-method bus service path interface name)
|
||
(dbus-introspect-get-signal bus service path interface name)
|
||
(dbus-introspect-get-property bus service path interface name))
|
||
(dbus-introspect-get-interface bus service path interface)))
|
||
result)
|
||
(dolist (elt (xml-get-children object 'annotation) result)
|
||
(add-to-list
|
||
'result (dbus-introspect-get-attribute elt "name") 'append))))
|
||
|
||
(defun dbus-introspect-get-annotation
|
||
(bus service path interface name annotation)
|
||
"Return ANNOTATION as XML object.
|
||
If NAME is `nil', ANNOTATION is a child of INTERFACE, otherwise
|
||
NAME must be the name of a \"method\", \"signal\", or
|
||
\"property\" object, where the ANNOTATION belongs to."
|
||
(let ((elt (xml-get-children
|
||
(if name
|
||
(or (dbus-introspect-get-method
|
||
bus service path interface name)
|
||
(dbus-introspect-get-signal
|
||
bus service path interface name)
|
||
(dbus-introspect-get-property
|
||
bus service path interface name))
|
||
(dbus-introspect-get-interface bus service path interface))
|
||
'annotation)))
|
||
(while (and elt
|
||
(not (string-equal
|
||
annotation
|
||
(dbus-introspect-get-attribute (car elt) "name"))))
|
||
(setq elt (cdr elt)))
|
||
(car elt)))
|
||
|
||
(defun dbus-introspect-get-argument-names (bus service path interface name)
|
||
"Return a list of all argument names as list of strings.
|
||
NAME must be a \"method\" or \"signal\" object.
|
||
|
||
Argument names are optional, the function can return `nil'
|
||
therefore, even if the method or signal has arguments."
|
||
(let ((object
|
||
(or (dbus-introspect-get-method bus service path interface name)
|
||
(dbus-introspect-get-signal bus service path interface name)))
|
||
result)
|
||
(dolist (elt (xml-get-children object 'arg) result)
|
||
(add-to-list
|
||
'result (dbus-introspect-get-attribute elt "name") 'append))))
|
||
|
||
(defun dbus-introspect-get-argument (bus service path interface name arg)
|
||
"Return argument ARG as XML object.
|
||
NAME must be a \"method\" or \"signal\" object. ARG must be a
|
||
string, element of the list returned by `dbus-introspect-get-argument-names'."
|
||
(let ((elt (xml-get-children
|
||
(or (dbus-introspect-get-method bus service path interface name)
|
||
(dbus-introspect-get-signal bus service path interface name))
|
||
'arg)))
|
||
(while (and elt
|
||
(not (string-equal
|
||
arg (dbus-introspect-get-attribute (car elt) "name"))))
|
||
(setq elt (cdr elt)))
|
||
(car elt)))
|
||
|
||
(defun dbus-introspect-get-signature
|
||
(bus service path interface name &optional direction)
|
||
"Return signature of a `method' or `signal', represented by NAME, as string.
|
||
If NAME is a `method', DIRECTION can be either \"in\" or \"out\".
|
||
If DIRECTION is `nil', \"in\" is assumed.
|
||
|
||
If NAME is a `signal', and DIRECTION is non-`nil', DIRECTION must
|
||
be \"out\"."
|
||
;; For methods, we use "in" as default direction.
|
||
(let ((object (or (dbus-introspect-get-method
|
||
bus service path interface name)
|
||
(dbus-introspect-get-signal
|
||
bus service path interface name))))
|
||
(when (and (string-equal
|
||
"method" (dbus-introspect-get-attribute object "name"))
|
||
(not (stringp direction)))
|
||
(setq direction "in"))
|
||
;; In signals, no direction is given.
|
||
(when (string-equal "signal" (dbus-introspect-get-attribute object "name"))
|
||
(setq direction nil))
|
||
;; Collect the signatures.
|
||
(mapconcat
|
||
'(lambda (x)
|
||
(let ((arg (dbus-introspect-get-argument
|
||
bus service path interface name x)))
|
||
(if (or (not (stringp direction))
|
||
(string-equal
|
||
direction
|
||
(dbus-introspect-get-attribute arg "direction")))
|
||
(dbus-introspect-get-attribute arg "type")
|
||
"")))
|
||
(dbus-introspect-get-argument-names bus service path interface name)
|
||
"")))
|
||
|
||
|
||
;;; D-Bus properties.
|
||
|
||
(defun dbus-get-property (bus service path interface property)
|
||
"Return the value of PROPERTY of INTERFACE.
|
||
It will be checked at BUS, SERVICE, PATH. The result can be any
|
||
valid D-Bus value, or `nil' if there is no PROPERTY."
|
||
(dbus-ignore-errors
|
||
;; We must check, whether the "org.freedesktop.DBus.Properties"
|
||
;; interface is supported; otherwise the call blocks.
|
||
(when
|
||
(member
|
||
"Get"
|
||
(dbus-introspect-get-method-names
|
||
bus service path "org.freedesktop.DBus.Properties"))
|
||
;; "Get" returns a variant, so we must use the car.
|
||
(car
|
||
(dbus-call-method
|
||
bus service path dbus-interface-properties
|
||
"Get" interface property)))))
|
||
|
||
(defun dbus-set-property (bus service path interface property value)
|
||
"Set value of PROPERTY of INTERFACE to VALUE.
|
||
It will be checked at BUS, SERVICE, PATH. When the value has
|
||
been set successful, the result is VALUE. Otherwise, `nil' is
|
||
returned."
|
||
(dbus-ignore-errors
|
||
(when
|
||
(and
|
||
;; We must check, whether the
|
||
;; "org.freedesktop.DBus.Properties" interface is supported;
|
||
;; otherwise the call blocks.
|
||
(member
|
||
"Set"
|
||
(dbus-introspect-get-method-names
|
||
bus service path "org.freedesktop.DBus.Properties"))
|
||
;; PROPERTY must be writable.
|
||
(string-equal
|
||
"readwrite"
|
||
(dbus-introspect-get-attribute
|
||
(dbus-introspect-get-property bus service path interface property)
|
||
"access")))
|
||
;; "Set" requires a variant.
|
||
(dbus-call-method
|
||
bus service path dbus-interface-properties
|
||
"Set" interface property (list :variant value))
|
||
;; Return VALUE.
|
||
(dbus-get-property bus service path interface property))))
|
||
|
||
(defun dbus-get-all-properties (bus service path interface)
|
||
"Return all properties of INTERFACE at BUS, SERVICE, PATH.
|
||
The result is a list of entries. Every entry is a cons of the
|
||
name of the property, and its value. If there are no properties,
|
||
`nil' is returned."
|
||
;; "org.freedesktop.DBus.Properties.GetAll" is not supported at
|
||
;; all interfaces. Therefore, we do it ourselves.
|
||
(dbus-ignore-errors
|
||
(let (result)
|
||
(dolist (property
|
||
(dbus-introspect-get-property-names
|
||
bus service path interface)
|
||
result)
|
||
(add-to-list
|
||
'result
|
||
(cons property (dbus-get-property bus service path interface property))
|
||
'append)))))
|
||
|
||
(provide 'dbus)
|
||
|
||
;; arch-tag: a47caf84-9162-4811-90cc-5d388e37b9bd
|
||
;;; dbus.el ends here
|