linux-container: container-script: Parse command line options.

* gnu/system/linux-container.scm (container-script): Accept command line
options to bind mount host directories into the container.
* doc/guix.texi (Invoking guix system): Document options.
This commit is contained in:
Ricardo Wurmus 2022-08-09 14:36:02 +02:00
parent f194df2bb4
commit 26af06b66b
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2 changed files with 76 additions and 25 deletions

View file

@ -37500,6 +37500,10 @@ guix system container my-config.scm \
--expose=$HOME --share=$HOME/tmp=/exchange
@end example
The @option{--share} and @option{--expose} options can also be passed to
the generated script to bind-mount additional directories into the
container.
@quotation Note
This option requires Linux-libre 3.19 or newer.
@end quotation

View file

@ -4,6 +4,7 @@
;;; Copyright © 2019 Arun Isaac <arunisaac@systemreboot.net>
;;; Copyright © 2020 Efraim Flashner <efraim@flashner.co.il>
;;; Copyright © 2020 Google LLC
;;; Copyright © 2022 Ricardo Wurmus <rekado@elephly.net>
;;;
;;; This file is part of GNU Guix.
;;;
@ -202,16 +203,49 @@ (define script
(guix build utils)
(guix i18n)
(guix diagnostics)
(srfi srfi-1))
(srfi srfi-1)
(srfi srfi-37)
(ice-9 match))
(define file-systems
(filter-map (lambda (spec)
(let* ((fs (spec->file-system spec))
(flags (file-system-flags fs)))
(and (or (not (memq 'bind-mount flags))
(file-exists? (file-system-device fs)))
fs)))
'#$specs))
(define (show-help)
(display (G_ "Usage: run-container [OPTION ...]
Run the container with the given options."))
(newline)
(display (G_ "
--share=SPEC share host file system with read/write access
according to SPEC"))
(display (G_ "
--expose=SPEC expose host file system directory as read-only
according to SPEC"))
(newline)
(display (G_ "
-h, --help display this help and exit"))
(newline))
(define %options
;; Specifications of the command-line options.
(list (option '(#\h "help") #f #f
(lambda args
(show-help)
(exit 0)))
(option '("share") #t #f
(lambda (opt name arg result)
(alist-cons 'file-system-mapping
(specification->file-system-mapping arg #t)
result)))
(option '("expose") #t #f
(lambda (opt name arg result)
(alist-cons 'file-system-mapping
(specification->file-system-mapping arg #f)
result)))))
(define (parse-options args options)
(args-fold args options
(lambda (opt name arg . rest)
(report-error (G_ "~A: unrecognized option~%") name)
(exit 1))
(lambda (op res) (cons op res))
'()))
(define (explain pid)
;; XXX: We can't quite call 'bindtextdomain' so there's actually
@ -225,22 +259,35 @@ (define (explain pid)
(info (G_ "or run 'sudo nsenter -a -t ~a' to get a shell into it.~%") pid)
(newline (guix-warning-port)))
(call-with-container file-systems
(lambda ()
(setenv "HOME" "/root")
(setenv "TMPDIR" "/tmp")
(setenv "GUIX_NEW_SYSTEM" #$os)
(for-each mkdir-p '("/run" "/bin" "/etc" "/home" "/var"))
(primitive-load (string-append #$os "/boot")))
;; A range of 65536 uid/gids is used to cover 16 bits worth of
;; users and groups, which is sufficient for most cases.
;;
;; See: http://www.freedesktop.org/software/systemd/man/systemd-nspawn.html#--private-users=
#:host-uids 65536
#:namespaces (if #$shared-network?
(delq 'net %namespaces)
%namespaces)
#:process-spawned-hook explain))))
(let* ((opts (parse-options (cdr (command-line)) %options))
(mappings (filter-map (match-lambda
(('file-system-mapping . mapping) mapping)
(_ #f))
opts))
(file-systems
(filter-map (lambda (fs)
(let ((flags (file-system-flags fs)))
(and (or (not (memq 'bind-mount flags))
(file-exists? (file-system-device fs)))
fs)))
(append (map file-system-mapping->bind-mount mappings)
(map spec->file-system '#$specs)))))
(call-with-container file-systems
(lambda ()
(setenv "HOME" "/root")
(setenv "TMPDIR" "/tmp")
(setenv "GUIX_NEW_SYSTEM" #$os)
(for-each mkdir-p '("/run" "/bin" "/etc" "/home" "/var"))
(primitive-load (string-append #$os "/boot")))
;; A range of 65536 uid/gids is used to cover 16 bits worth of
;; users and groups, which is sufficient for most cases.
;;
;; See: http://www.freedesktop.org/software/systemd/man/systemd-nspawn.html#--private-users=
#:host-uids 65536
#:namespaces (if #$shared-network?
(delq 'net %namespaces)
%namespaces)
#:process-spawned-hook explain)))))
(gexp->script "run-container" script)))