bug#54762: closed ([PATCH] home: symlink-manager: Use no-follow version of file-exists?.)

[GNU bug Tracking System]

Your message dated Sat, 09 Apr 2022 23:57:03 +0200
with message-id <87lewd7weo.fsf_-_@gnu.org>
and subject line Re: bug#54762: [PATCH] home: symlink-manager: Use no-follow 
version of file-exists?.
has caused the debbugs.gnu.org bug report #54762,
regarding [PATCH] home: symlink-manager: Use no-follow version of file-exists?.
to be marked as done.

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-- 
54762: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=54762
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--- Begin Message --- Subject: [PATCH] home: symlink-manager: Use no-follow version of file-exists?. Date: Thu, 7 Apr 2022 11:22:48 +0300

* gnu/home/services/symlink-manager.scm (update-symlinks-script): Use
no-follow version of file-exists?.
---
file-exists? returns #f on dangling symlinks, which makes such files
"invisible" during the cleanup process and breaks activation of home
environment.

gnu/home/services/symlink-manager.scm | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/gnu/home/services/symlink-manager.scm 
b/gnu/home/services/symlink-manager.scm
index 6d19258ec7..bb67152e5b 100644
--- a/gnu/home/services/symlink-manager.scm
+++ b/gnu/home/services/symlink-manager.scm
@@ -85,6 +85,13 @@ (define (target-file file)
            ;; 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."
+           (or (file-exists? file)
+               (and=> (false-if-exception (lstat file))
+                      (lambda (x)
+                        (equal? (stat:type x) 'symlink)))))
+
          (define (symlink-to-store? file)
            (catch 'system-error
              (lambda ()
@@ -123,7 +130,7 @@ (define (strip file)
             (const #t)
             (lambda (file stat _)                 ;leaf
               (let ((file (target-file (strip file))))
-                (when (file-exists? 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.
@@ -183,7 +190,7 @@ (define (source-file file)
             (lambda (file stat result)            ;leaf
               (let ((source (source-file (strip file)))
                     (target (target-file (strip file))))
-                (when (file-exists? target)
+                (when (no-follow-file-exists? target)
                   (backup-file (strip file)))
                 (format #t (G_ "Symlinking ~a -> ~a...")
                         target source)
@@ -192,7 +199,7 @@ (define (source-file file)
             (lambda (directory stat result)       ;down
               (unless (string=? directory config-file-directory)
                 (let ((target (target-file (strip directory))))
-                  (when (and (file-exists? target)
+                  (when (and (no-follow-file-exists? target)
                              (not (file-is-directory? target)))
                     (backup-file (strip directory)))
 
-- 
2.34.0

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--- End Message ---

> --- Begin Message ---
>
>
>
> Subject: 
>
> Re: bug#54762: [PATCH] home: symlink-manager: Use no-follow version of file-exists?.
>
>
>
>
> Date: 
>
> Sat, 09 Apr 2022 23:57:03 +0200
>
>
>
>
> User-agent: 
>
> Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux)
>
>
>
>
> Hi,
>
> Andrew Tropin <andrew@trop.in> skribis:
>
> > From 92ee52a96d536cba2b3b473f99e8f36646da81fd Mon Sep 17 00:00:00 2001
> > From: Andrew Tropin <andrew@trop.in>
> > Date: Thu, 7 Apr 2022 11:22:48 +0300
> > Subject: [PATCH v2] home: symlink-manager: Use no-follow version of
> >  file-exists?.
> >
> > * gnu/home/services/symlink-manager.scm (update-symlinks-script): Use
> > no-follow version of file-exists?.
>
> Applied, thanks!
>
> Ludo’.
>
>
> --- End Message ---