;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2014 Ludovic Courtès <ludo@gnu.org> ;;; ;;; This file is part of GNU Guix. ;;; ;;; GNU Guix 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 Guix 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 Guix. If not, see <http://www.gnu.org/licenses/>. (define-module (gnu services dbus) #:use-module (gnu services) #:use-module (gnu system shadow) #:use-module (gnu packages glib) #:use-module (guix monads) #:use-module (guix gexp) #:export (dbus-service)) ;;; Commentary: ;;; ;;; This module supports the configuration of the D-Bus message bus ;;; (http://dbus.freedesktop.org/). D-Bus is an inter-process communication ;;; facility. Its "system bus" is used to allow system services to ;;; communicate and be notified of system-wide events. ;;; ;;; Code: (define (dbus-configuration-directory dbus services) "Return a configuration directory for @var{dbus} that includes the @code{etc/dbus-1/system.d} directories of each package listed in @var{services}." (define build #~(begin (use-modules (sxml simple)) (define (services->sxml services) ;; Return the SXML 'includedir' clauses for DIRS. `(busconfig ,@(map (lambda (dir) `(includedir ,(string-append dir "/etc/dbus-1/system.d"))) services))) (mkdir #$output) (copy-file (string-append #$dbus "/etc/dbus-1/system.conf") (string-append #$output "/system.conf")) ;; The default 'system.conf' has an <includedir> clause for ;; 'system.d', so create it. (mkdir (string-append #$output "/system.d")) ;; 'system-local.conf' is automatically included by the default ;; 'system.conf', so this is where we stuff our own things. (call-with-output-file (string-append #$output "/system-local.conf") (lambda (port) (sxml->xml (services->sxml (list #$@services)) port))))) (gexp->derivation "dbus-configuration" build)) (define* (dbus-service services #:key (dbus dbus)) "Return a service that runs the system bus, using @var{dbus}, with support for @var{services}. @var{services} must be a list of packages that provide an @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration and policy files. For example, to allow avahi-daemon to use the system bus, @var{services} must be equal to @code{(list avahi)}." (mlet %store-monad ((conf (dbus-configuration-directory dbus services))) (return (service (documentation "Run the D-Bus system daemon.") (provision '(dbus-system)) (requirement '(user-processes)) (start #~(make-forkexec-constructor (list (string-append #$dbus "/bin/dbus-daemon") "--nofork" (string-append "--config-file=" #$conf "/system.conf")))) (stop #~(make-kill-destructor)) (user-groups (list (user-group (name "messagebus") (system? #t)))) (user-accounts (list (user-account (name "messagebus") (group "messagebus") (system? #t) (comment "D-Bus system bus user") (home-directory "/var/run/dbus") (shell "/run/current-system/profile/sbin/nologin")))) (activate #~(begin (use-modules (guix build utils)) (mkdir-p "/var/run/dbus") (let ((user (getpwnam "messagebus"))) (chown "/var/run/dbus" (passwd:uid user) (passwd:gid user))) (unless (file-exists? "/etc/machine-id") (format #t "creating /etc/machine-id...~%") (let ((prog (string-append #$dbus "/bin/dbus-uuidgen"))) ;; XXX: We can't use 'system' because the initrd's ;; guile system(3) only works when 'sh' is in $PATH. (let ((pid (primitive-fork))) (if (zero? pid) (call-with-output-file "/etc/machine-id" (lambda (port) (close-fdes 1) (dup2 (port->fdes port) 1) (execl prog))) (waitpid pid))))))))))) ;;; dbus.scm ends here