252 lines
10 KiB
Scheme
252 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>
|
|
;;;
|
|
;;; 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)
|
|
|
|
#:export (home-symlink-manager-service-type))
|
|
|
|
;;; Comment:
|
|
;;;
|
|
;;; symlink-manager cares about configuration files: it backs up files
|
|
;;; created by user, removes symlinks and directories created by a
|
|
;;; previous generation, and creates new directories and symlinks to
|
|
;;; configuration files according to the content of files/ directory
|
|
;;; (created by home-files-service) of the current home environment
|
|
;;; generation.
|
|
;;;
|
|
;;; Code:
|
|
|
|
(define (update-symlinks-script)
|
|
(program-file
|
|
"update-symlinks"
|
|
#~(begin
|
|
(use-modules (ice-9 ftw)
|
|
(ice-9 curried-definitions)
|
|
(ice-9 match)
|
|
(srfi srfi-1)
|
|
(guix i18n))
|
|
#$%initialize-gettext
|
|
(define ((simplify-file-tree parent) file)
|
|
"Convert the result produced by `file-system-tree' to less
|
|
verbose and more suitable for further processing format.
|
|
|
|
Extract dir/file info from stat and compose a relative path to the
|
|
root of the file tree.
|
|
|
|
Sample output:
|
|
|
|
((dir . \".\")
|
|
((dir . \"config\")
|
|
((dir . \"config/fontconfig\")
|
|
(file . \"config/fontconfig/fonts.conf\"))
|
|
((dir . \"config/isync\")
|
|
(file . \"config/isync/mbsyncrc\"))))
|
|
"
|
|
(match file
|
|
((name stat) `(file . ,(string-append parent name)))
|
|
((name stat children ...)
|
|
(cons `(dir . ,(string-append parent name))
|
|
(map (simplify-file-tree
|
|
(if (equal? name ".")
|
|
""
|
|
(string-append parent name "/")))
|
|
children)))))
|
|
|
|
(define ((file-tree-traverse preordering) node)
|
|
"Traverses the file tree in different orders, depending on PREORDERING.
|
|
|
|
if PREORDERING is @code{#t} resulting list will contain directories
|
|
before files located in those directories, otherwise directory will
|
|
appear only after all nested items already listed."
|
|
(let ((prepend (lambda (a b) (append b a))))
|
|
(match node
|
|
(('file . path) (list node))
|
|
((('dir . path) . rest)
|
|
((if preordering append prepend)
|
|
(list (cons 'dir path))
|
|
(append-map (file-tree-traverse preordering) rest))))))
|
|
|
|
(use-modules (guix build utils))
|
|
|
|
(let* ((config-home (or (getenv "XDG_CONFIG_HOME")
|
|
(string-append (getenv "HOME") "/.config")))
|
|
|
|
(he-path (string-append (getenv "HOME") "/.guix-home"))
|
|
(new-he-path (string-append he-path ".new"))
|
|
(new-home (getenv "GUIX_NEW_HOME"))
|
|
(old-home (getenv "GUIX_OLD_HOME"))
|
|
|
|
(new-files-path (string-append new-home "/files"))
|
|
;; Trailing dot is required, because files itself is symlink and
|
|
;; to make file-system-tree works it should be a directory.
|
|
(new-files-dir-path (string-append new-files-path "/."))
|
|
|
|
(home-path (getenv "HOME"))
|
|
(backup-dir (string-append home-path "/"
|
|
(number->string (current-time))
|
|
"-guix-home-legacy-configs-backup"))
|
|
|
|
(old-tree (if old-home
|
|
((simplify-file-tree "")
|
|
(file-system-tree
|
|
(string-append old-home "/files/.")))
|
|
#f))
|
|
(new-tree ((simplify-file-tree "")
|
|
(file-system-tree new-files-dir-path)))
|
|
|
|
(get-source-path
|
|
(lambda (path)
|
|
(readlink (string-append new-files-path "/" path))))
|
|
|
|
(get-target-path
|
|
(lambda (path)
|
|
(string-append home-path "/." path)))
|
|
|
|
(get-backup-path
|
|
(lambda (path)
|
|
(string-append backup-dir "/." path)))
|
|
|
|
(directory?
|
|
(lambda (path)
|
|
(equal? (stat:type (stat path)) 'directory)))
|
|
|
|
(empty-directory?
|
|
(lambda (dir)
|
|
(equal? (scandir dir) '("." ".."))))
|
|
|
|
(symlink-to-store?
|
|
(lambda (path)
|
|
(and
|
|
(equal? (stat:type (lstat path)) 'symlink)
|
|
(store-file-name? (readlink path)))))
|
|
|
|
(backup-file
|
|
(lambda (path)
|
|
(mkdir-p backup-dir)
|
|
(format #t (G_ "Backing up ~a...") (get-target-path path))
|
|
(mkdir-p (dirname (get-backup-path path)))
|
|
(rename-file (get-target-path path) (get-backup-path path))
|
|
(display (G_ " done\n"))))
|
|
|
|
(cleanup-symlinks
|
|
(lambda ()
|
|
(let ((to-delete ((file-tree-traverse #f) old-tree)))
|
|
(display
|
|
(G_
|
|
"Cleaning up symlinks from previous home-environment.\n\n"))
|
|
(map
|
|
(match-lambda
|
|
(('dir . ".")
|
|
(display (G_ "Cleanup finished.\n\n")))
|
|
|
|
(('dir . path)
|
|
(if (and
|
|
(file-exists? (get-target-path path))
|
|
(directory? (get-target-path path))
|
|
(empty-directory? (get-target-path path)))
|
|
(begin
|
|
(format #t (G_ "Removing ~a...")
|
|
(get-target-path path))
|
|
(rmdir (get-target-path path))
|
|
(display (G_ " done\n")))
|
|
(format
|
|
#t
|
|
(G_ "Skipping ~a (not an empty directory)... done\n")
|
|
(get-target-path path))))
|
|
|
|
(('file . path)
|
|
(when (file-exists? (get-target-path path))
|
|
;; 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? (get-target-path path))
|
|
(begin
|
|
(format #t (G_ "Removing ~a...") (get-target-path path))
|
|
(delete-file (get-target-path path))
|
|
(display (G_ " done\n")))
|
|
(format
|
|
#t
|
|
(G_ "Skipping ~a (not a symlink to store)... done\n")
|
|
(get-target-path path))))))
|
|
to-delete))))
|
|
|
|
(create-symlinks
|
|
(lambda ()
|
|
(let ((to-create ((file-tree-traverse #t) new-tree)))
|
|
(map
|
|
(match-lambda
|
|
(('dir . ".")
|
|
(display
|
|
(G_ "New symlinks to home-environment will be created soon.\n"))
|
|
(format
|
|
#t (G_ "All conflicting files will go to ~a.\n\n") backup-dir))
|
|
|
|
(('dir . path)
|
|
(let ((target-path (get-target-path path)))
|
|
(when (and (file-exists? target-path)
|
|
(not (directory? target-path)))
|
|
(backup-file path))
|
|
|
|
(if (file-exists? target-path)
|
|
(format
|
|
#t (G_ "Skipping ~a (directory already exists)... done\n")
|
|
target-path)
|
|
(begin
|
|
(format #t (G_ "Creating ~a...") target-path)
|
|
(mkdir target-path)
|
|
(display (G_ " done\n"))))))
|
|
|
|
(('file . path)
|
|
(when (file-exists? (get-target-path path))
|
|
(backup-file path))
|
|
(format #t (G_ "Symlinking ~a -> ~a...")
|
|
(get-target-path path) (get-source-path path))
|
|
(symlink (get-source-path path) (get-target-path path))
|
|
(display (G_ " done\n"))))
|
|
to-create)))))
|
|
|
|
(when old-tree
|
|
(cleanup-symlinks))
|
|
|
|
(create-symlinks)
|
|
|
|
(symlink new-home new-he-path)
|
|
(rename-file new-he-path he-path)
|
|
|
|
(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.")))
|