summary refs log tree commit diff
path: root/gnu/services/audio.scm
blob: 5729b6bb0e1d65782512eefd8e8868e273a97481 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
;;; 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)")
   (provision '(mpd))
   (start #~(make-forkexec-constructor
             (list #$(file-append mpd "/bin/mpd")
                   "--no-daemon"
                   #$(mpd-config->file config))
             #:pid-file #$(mpd-file-name config "pid")
             #:environment-variables
             ;; Required to detect PulseAudio when run under a user account.
             (list (string-append
                    "XDG_RUNTIME_DIR=/run/user/"
                    (number->string
                     (passwd:uid
                      (getpwnam #$(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 "")))
          (mkdir-p directory)
          (chown 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))))