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
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2018 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019, 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 installer utils)
#:use-module (guix utils)
#:use-module (guix build utils)
#:use-module (guix i18n)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-34)
#:use-module (ice-9 match)
#:use-module (ice-9 rdelim)
#:use-module (ice-9 regex)
#:use-module (ice-9 format)
#:use-module (ice-9 textual-ports)
#:export (read-lines
read-all
nearest-exact-integer
read-percentage
run-command
syslog-port
syslog
with-server-socket
current-server-socket
current-clients
send-to-clients))
(define* (read-lines #:optional (port (current-input-port)))
"Read lines from PORT and return them as a list."
(let loop ((line (read-line port))
(lines '()))
(if (eof-object? line)
(reverse lines)
(loop (read-line port)
(cons line lines)))))
(define (read-all file)
"Return the content of the given FILE as a string."
(call-with-input-file file
get-string-all))
(define (nearest-exact-integer x)
"Given a real number X, return the nearest exact integer, with ties going to
the nearest exact even integer."
(inexact->exact (round x)))
(define (read-percentage percentage)
"Read PERCENTAGE string and return the corresponding percentage as a
number. If no percentage is found, return #f"
(let ((result (string-match "^([0-9]+)%$" percentage)))
(and result
(string->number (match:substring result 1)))))
(define* (run-command command #:key locale)
"Run COMMAND, a list of strings, in the given LOCALE. Return true if
COMMAND exited successfully, #f otherwise."
(define env (environ))
(define (pause)
(format #t (G_ "Press Enter to continue.~%"))
(send-to-clients '(pause))
(environ env) ;restore environment variables
(match (select (cons (current-input-port) (current-clients))
'() '())
(((port _ ...) _ _)
(read-line port))))
(setenv "PATH" "/run/current-system/profile/bin")
(when locale
(let ((supported? (false-if-exception
(setlocale LC_ALL locale))))
;; If LOCALE is not supported, then set LANGUAGE, which might at
;; least give us translated messages.
(if supported?
(setenv "LC_ALL" locale)
(setenv "LANGUAGE"
(string-take locale
(string-index locale #\_))))))
(guard (c ((invoke-error? c)
(newline)
(format (current-error-port)
(G_ "Command failed with exit code ~a.~%")
(invoke-error-exit-status c))
(syslog "command ~s failed with exit code ~a"
command (invoke-error-exit-status c))
(pause)
#f))
(syslog "running command ~s~%" command)
(apply invoke command)
(syslog "command ~s succeeded~%" command)
(newline)
(pause)
#t))
;;;
;;; Logging.
;;;
(define (open-syslog-port)
"Return an open port (a socket) to /dev/log or #f if that wasn't possible."
(let ((sock (socket AF_UNIX SOCK_DGRAM 0)))
(catch 'system-error
(lambda ()
(connect sock AF_UNIX "/dev/log")
(setvbuf sock 'line)
sock)
(lambda args
(close-port sock)
#f))))
(define syslog-port
(let ((port #f))
(lambda ()
"Return an output port to syslog."
(unless port
(set! port (open-syslog-port)))
(or port (%make-void-port "w")))))
(define-syntax syslog
(lambda (s)
"Like 'format', but write to syslog."
(syntax-case s ()
((_ fmt args ...)
(string? (syntax->datum #'fmt))
(with-syntax ((fmt (string-append "installer[~d]: "
(syntax->datum #'fmt))))
#'(format (syslog-port) fmt (getpid) args ...))))))
;;;
;;; Client protocol.
;;;
(define %client-socket-file
;; Unix-domain socket where the installer accepts connections.
"/var/guix/installer-socket")
(define current-server-socket
;; Socket on which the installer is currently accepting connections, or #f.
(make-parameter #f))
(define current-clients
;; List of currently connected clients.
(make-parameter '()))
(define* (open-server-socket
#:optional (socket-file %client-socket-file))
"Open SOCKET-FILE as a Unix-domain socket to accept incoming connections and
return it."
(mkdir-p (dirname socket-file))
(when (file-exists? socket-file)
(delete-file socket-file))
(let ((sock (socket AF_UNIX SOCK_STREAM 0)))
(bind sock AF_UNIX socket-file)
(listen sock 0)
sock))
(define (call-with-server-socket thunk)
(if (current-server-socket)
(thunk)
(let ((socket (open-server-socket)))
(dynamic-wind
(const #t)
(lambda ()
(parameterize ((current-server-socket socket))
(thunk)))
(lambda ()
(close-port socket))))))
(define-syntax-rule (with-server-socket exp ...)
"Evaluate EXP with 'current-server-socket' parameterized to a currently
accepting socket."
(call-with-server-socket (lambda () exp ...)))
(define* (send-to-clients exp)
"Send EXP to all the current clients."
(define remainder
(fold (lambda (client remainder)
(catch 'system-error
(lambda ()
(write exp client)
(newline client)
(force-output client)
(cons client remainder))
(lambda args
;; We might get EPIPE if the client disconnects; when that
;; happens, remove CLIENT from the set of available clients.
(let ((errno (system-error-errno args)))
(if (memv errno (list EPIPE ECONNRESET ECONNABORTED))
(begin
(syslog "removing client ~s due to ~s while replying~%"
(fileno client) (strerror errno))
(false-if-exception (close-port client))
remainder)
(cons client remainder))))))
'()
(current-clients)))
(current-clients (reverse remainder))
exp)
|