guix/gnu/services/audio.scm
Ludovic Courtès ce3b5e5a8d
services: mpd: Make /var/run/mpd/USER user-owned.
Fixes <https://bugs.gnu.org/44820>.
Reported by Simon <lists@netpanic.org>.

This is a followup to bb124f6e9c.

* gnu/services/audio.scm (mpd-service-activation): Chown the parent of
DIRECTORY as well.
2020-12-06 23:18:08 +01:00

199 lines
7.1 KiB
Scheme

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2017 Peter Mikkelsen <petermikkelsen10@gmail.com>
;;; Copyright © 2019 Ricardo Wurmus <rekado@elephly.net>
;;; Copyright © 2020 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 audio)
#:use-module (guix gexp)
#:use-module (gnu services)
#:use-module (gnu services shepherd)
#:use-module (gnu system shadow)
#:use-module (gnu packages admin)
#:use-module (gnu packages mpd)
#:use-module (guix records)
#:use-module (ice-9 match)
#:use-module (ice-9 format)
#:export (mpd-output
mpd-output?
mpd-configuration
mpd-configuration?
mpd-service-type))
;;; Commentary:
;;;
;;; Audio related services
;;;
;;; Code:
(define-record-type* <mpd-output>
mpd-output make-mpd-output
mpd-output?
(type mpd-output-type
(default "pulse"))
(name mpd-output-name
(default "MPD"))
(enabled? mpd-output-enabled?
(default #t))
(tags? mpd-output-tags?
(default #t))
(always-on? mpd-output-always-on?
(default #f))
(mixer-type mpd-output-mixer-type
;; valid: hardware, software, null, none
(default #f))
(extra-options mpd-output-extra-options
(default '())))
(define-record-type* <mpd-configuration>
mpd-configuration make-mpd-configuration
mpd-configuration?
(user mpd-configuration-user
(default "mpd"))
(music-dir mpd-configuration-music-dir
(default "~/Music"))
(playlist-dir mpd-configuration-playlist-dir
(default "~/.mpd/playlists"))
(db-file mpd-configuration-db-file
(default "~/.mpd/tag_cache"))
(state-file mpd-configuration-state-file
(default "~/.mpd/state"))
(sticker-file mpd-configuration-sticker-file
(default "~/.mpd/sticker.sql"))
(port mpd-configuration-port
(default "6600"))
(address mpd-configuration-address
(default "any"))
(outputs mpd-configuration-outputs
(default (list (mpd-output)))))
(define (mpd-output->string output)
"Convert the OUTPUT of type <mpd-output> to a configuration file snippet."
(let ((extra (string-join
(map (match-lambda
((key . value)
(format #f " ~a \"~a\""
(string-map
(lambda (c) (if (char=? c #\-) #\_ c))
(symbol->string key))
value)))
(mpd-output-extra-options output))
"\n")))
(format #f "\
audio_output {
type \"~a\"
name \"~a\"
~:[ enabled \"no\"~%~;~]\
~:[ tags \"no\"~%~;~]\
~:[~; always_on \"yes\"~%~]\
~@[ mixer_type \"~a\"~%~]\
~a~%}~%"
(mpd-output-type output)
(mpd-output-name output)
(mpd-output-enabled? output)
(mpd-output-tags? output)
(mpd-output-always-on? output)
(mpd-output-mixer-type output)
extra)))
(define (mpd-config->file config)
(apply
mixed-text-file "mpd.conf"
"pid_file \"" (mpd-file-name config "pid") "\"\n"
(append (map mpd-output->string
(mpd-configuration-outputs config))
(map (match-lambda
((config-name config-val)
(string-append config-name " \"" (config-val config) "\"\n")))
`(("user" ,mpd-configuration-user)
("music_directory" ,mpd-configuration-music-dir)
("playlist_directory" ,mpd-configuration-playlist-dir)
("db_file" ,mpd-configuration-db-file)
("state_file" ,mpd-configuration-state-file)
("sticker_file" ,mpd-configuration-sticker-file)
("port" ,mpd-configuration-port)
("bind_to_address" ,mpd-configuration-address))))))
(define (mpd-file-name config file)
"Return a path in /var/run/mpd/ that is writable
by @code{user} from @code{config}."
(string-append "/var/run/mpd/"
(mpd-configuration-user config)
"/" file))
(define (mpd-shepherd-service config)
(shepherd-service
(documentation "Run the MPD (Music Player Daemon)")
(requirement '(user-processes))
(provision '(mpd))
(start #~(make-forkexec-constructor
(list #$(file-append mpd "/bin/mpd")
"--no-daemon"
#$(mpd-config->file config))
#:environment-variables
;; Required to detect PulseAudio when run under a user account.
(list (string-append
"XDG_RUNTIME_DIR=/run/user/"
(number->string
(passwd:uid
(getpwnam #$(mpd-configuration-user config))))))
#:log-file #$(mpd-file-name config "log")))
(stop #~(make-kill-destructor))))
(define (mpd-service-activation config)
(with-imported-modules '((guix build utils))
#~(begin
(use-modules (guix build utils))
(define %user
(getpw #$(mpd-configuration-user config)))
(let ((directory #$(mpd-file-name config ".mpd")))
(mkdir-p directory)
(chown directory (passwd:uid %user) (passwd:gid %user))
;; Make /var/run/mpd/USER user-owned as well.
(chown (dirname directory)
(passwd:uid %user) (passwd:gid %user))))))
(define %mpd-accounts
;; Default account and group for MPD.
(list (user-group (name "mpd") (system? #t))
(user-account
(name "mpd")
(group "mpd")
(system? #t)
(comment "Music Player Daemon (MPD) user")
;; Note: /var/run/mpd hosts one sub-directory per user, of which
;; /var/run/mpd/mpd corresponds to the "mpd" user.
(home-directory "/var/run/mpd/mpd")
(shell (file-append shadow "/sbin/nologin")))))
(define mpd-service-type
(service-type
(name 'mpd)
(description "Run the Music Player Daemon (MPD).")
(extensions
(list (service-extension shepherd-root-service-type
(compose list mpd-shepherd-service))
(service-extension account-service-type
(const %mpd-accounts))
(service-extension activation-service-type
mpd-service-activation)))
(default-value (mpd-configuration))))