b1ec85533a
* gnu/home/services/symlink-manager.scm (update-symlinks-script): Allow busy device skip. Change-Id: Iff91c8a30309d25c02a8311d8d5ddbf54e90f5ad Signed-off-by: Ludovic Courtès <ludo@gnu.org>
255 lines
10 KiB
Scheme
255 lines
10 KiB
Scheme
;;; GNU Guix --- Functional package management for GNU
|
|
;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
|
|
;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
|
|
;;; Copyright © 2022 Ludovic Courtès <ludo@gnu.org>
|
|
;;; Copyright © 2024 Nicolas Graves <ngraves@ngraves.fr>
|
|
;;;
|
|
;;; 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 home services symlink-manager)
|
|
#:use-module (gnu home services)
|
|
#:use-module (guix gexp)
|
|
#:use-module (guix modules)
|
|
#:export (home-symlink-manager-service-type))
|
|
|
|
;;; Comment:
|
|
;;;
|
|
;;; symlink-manager cares about xdg configurations and other files: it backs
|
|
;;; up files created by user, removes symlinks and directories created by a
|
|
;;; previous generation, and creates new directories and symlinks to files
|
|
;;; according to the content of directories (created by home-files-service) of
|
|
;;; the current home environment generation.
|
|
;;;
|
|
;;; Code:
|
|
|
|
(define (update-symlinks-script)
|
|
(program-file
|
|
"update-symlinks"
|
|
(with-imported-modules (source-module-closure
|
|
'((guix build utils)
|
|
(guix i18n)))
|
|
#~(begin
|
|
(use-modules (ice-9 ftw)
|
|
(ice-9 match)
|
|
(srfi srfi-1)
|
|
(guix i18n)
|
|
(guix build utils))
|
|
|
|
(define home-directory
|
|
(getenv "HOME"))
|
|
|
|
(define xdg-config-home
|
|
(or (getenv "XDG_CONFIG_HOME")
|
|
(string-append (getenv "HOME") "/.config")))
|
|
|
|
(define xdg-data-home
|
|
(or (getenv "XDG_DATA_HOME")
|
|
(string-append (getenv "HOME") "/.local/share")))
|
|
|
|
(define backup-directory
|
|
(string-append home-directory "/" (number->string (current-time))
|
|
"-guix-home-legacy-configs-backup"))
|
|
|
|
(define (preprocess-file file)
|
|
"If file is in XDG-CONFIGURATION-FILES-DIRECTORY use
|
|
subdirectory from XDG_CONFIG_HOME to generate a target path."
|
|
(cond
|
|
((string-prefix? #$xdg-configuration-files-directory file)
|
|
(string-append
|
|
(substring xdg-config-home
|
|
(1+ (string-length home-directory)))
|
|
(substring file
|
|
(string-length #$xdg-configuration-files-directory))))
|
|
((string-prefix? #$xdg-data-files-directory file)
|
|
(string-append
|
|
(substring xdg-data-home
|
|
(1+ (string-length home-directory)))
|
|
(substring file
|
|
(string-length #$xdg-data-files-directory))))
|
|
(else file)))
|
|
|
|
(define (target-file file)
|
|
;; Return the target of FILE, a config file name sans leading dot
|
|
;; such as "config/fontconfig/fonts.conf" or "bashrc".
|
|
(string-append home-directory "/" (preprocess-file file)))
|
|
|
|
(define (no-follow-file-exists? file)
|
|
"Return #t if file exists, even if it's a dangling symlink."
|
|
(->bool (false-if-exception (lstat file))))
|
|
|
|
(define (symlink-to-store? file)
|
|
(catch 'system-error
|
|
(lambda ()
|
|
(store-file-name? (readlink file)))
|
|
(lambda args
|
|
(if (= EINVAL (system-error-errno args))
|
|
#f
|
|
(apply throw args)))))
|
|
|
|
(define (backup-file file)
|
|
(define backup
|
|
(string-append backup-directory "/" (preprocess-file file)))
|
|
|
|
(mkdir-p backup-directory)
|
|
(format #t (G_ "Backing up ~a...") (target-file file))
|
|
(mkdir-p (dirname backup))
|
|
(rename-file (target-file file) backup)
|
|
(display (G_ " done\n")))
|
|
|
|
(define (cleanup-symlinks home-generation)
|
|
;; Delete from $HOME files that originate in HOME-GENERATION, the
|
|
;; store item containing a home generation.
|
|
(define config-file-directory
|
|
;; Note: Trailing slash is needed because "files" is a symlink.
|
|
(string-append home-generation "/" #$home-files-directory "/"))
|
|
|
|
(define (strip file)
|
|
(string-drop file
|
|
(+ 1 (string-length config-file-directory))))
|
|
|
|
(format #t (G_ "Cleaning up symlinks from previous home at ~a.~%")
|
|
home-generation)
|
|
(newline)
|
|
|
|
(file-system-fold
|
|
(const #t)
|
|
(lambda (file stat _) ;leaf
|
|
(let ((file (target-file (strip file))))
|
|
(when (no-follow-file-exists? file)
|
|
;; DO NOT remove the file if it is no longer a symlink to
|
|
;; the store, it will be backed up later during
|
|
;; create-symlinks phase.
|
|
(if (symlink-to-store? file)
|
|
(begin
|
|
(format #t (G_ "Removing ~a...") file)
|
|
(delete-file file)
|
|
(display (G_ " done\n")))
|
|
(format
|
|
#t
|
|
(G_ "Skipping ~a (not a symlink to store)... done\n")
|
|
file)))))
|
|
|
|
(const #t) ;down
|
|
(lambda (directory stat _) ;up
|
|
(unless (string=? directory config-file-directory)
|
|
(let ((directory (target-file (strip directory))))
|
|
(catch 'system-error
|
|
(lambda ()
|
|
(rmdir directory)
|
|
(format #t (G_ "Removed ~a.\n") directory))
|
|
(lambda args
|
|
(let ((errno (system-error-errno args)))
|
|
(cond
|
|
((= ENOTEMPTY errno)
|
|
(format
|
|
#t
|
|
(G_ "Skipping ~a (not an empty directory)... done\n")
|
|
directory))
|
|
;; This happens when the directory is a mounted device.
|
|
((= EBUSY errno)
|
|
(format
|
|
#t
|
|
(G_ "Skipping ~a (underlying device is busy)... done\n")
|
|
directory))
|
|
((= ENOENT errno) #t)
|
|
((= ENOTDIR errno) #t)
|
|
(else
|
|
(apply throw args)))))))))
|
|
(const #t) ;skip
|
|
(const #t) ;error
|
|
#t ;init
|
|
config-file-directory
|
|
lstat)
|
|
|
|
(display (G_ "Cleanup finished.\n\n")))
|
|
|
|
(define (create-symlinks home-generation)
|
|
;; Create in $HOME symlinks for the files in HOME-GENERATION.
|
|
(define config-file-directory
|
|
;; Note: Trailing slash is needed because "files" is a symlink.
|
|
(string-append home-generation "/" #$home-files-directory "/"))
|
|
|
|
(define (strip file)
|
|
(string-drop file
|
|
(+ 1 (string-length config-file-directory))))
|
|
|
|
(define (source-file file)
|
|
(readlink (string-append config-file-directory file)))
|
|
|
|
(file-system-fold
|
|
(const #t) ;enter?
|
|
(lambda (file stat result) ;leaf
|
|
(let ((source (source-file (strip file)))
|
|
(target (target-file (strip file))))
|
|
(when (no-follow-file-exists? target)
|
|
(backup-file (strip file)))
|
|
(format #t (G_ "Symlinking ~a -> ~a...")
|
|
target source)
|
|
(symlink source target)
|
|
(display (G_ " done\n"))))
|
|
(lambda (directory stat result) ;down
|
|
(unless (string=? directory config-file-directory)
|
|
(let ((target (target-file (strip directory))))
|
|
(when (and (no-follow-file-exists? target)
|
|
(not (file-is-directory? target)))
|
|
(backup-file (strip directory)))
|
|
|
|
(catch 'system-error
|
|
(lambda ()
|
|
(mkdir target))
|
|
(lambda args
|
|
(let ((errno (system-error-errno args)))
|
|
(unless (= EEXIST errno)
|
|
(format #t (G_ "failed to create directory ~a: ~s~%")
|
|
target (strerror errno))
|
|
(apply throw args))))))))
|
|
(const #t) ;up
|
|
(const #t) ;skip
|
|
(const #t) ;error
|
|
#t ;init
|
|
config-file-directory))
|
|
|
|
#$%initialize-gettext
|
|
|
|
(let* ((home (string-append home-directory "/.guix-home"))
|
|
(pivot (string-append home ".new"))
|
|
(new-home (getenv "GUIX_NEW_HOME"))
|
|
(old-home (getenv "GUIX_OLD_HOME")))
|
|
(when old-home
|
|
(cleanup-symlinks old-home))
|
|
|
|
(create-symlinks new-home)
|
|
|
|
(symlink new-home pivot)
|
|
(rename-file pivot home)
|
|
|
|
(display (G_" done\nFinished updating symlinks.\n\n")))))))
|
|
|
|
(define (update-symlinks-gexp _)
|
|
#~(primitive-load #$(update-symlinks-script)))
|
|
|
|
(define home-symlink-manager-service-type
|
|
(service-type (name 'home-symlink-manager)
|
|
(extensions
|
|
(list
|
|
(service-extension
|
|
home-activation-service-type
|
|
update-symlinks-gexp)))
|
|
(default-value #f)
|
|
(description "Provide an @code{update-symlinks}
|
|
script, which creates symlinks to configuration files and directories
|
|
on every activation. If an existing file would be overwritten by a
|
|
symlink, backs up that file first.")))
|