Fix Bug#33194

* lisp/autorevert.el (auto-revert-notify-add-watch):
Handle buffers with same descriptor properly.
(auto-revert-notify-handler): Handle all buffers with same
descriptor.  (Bug#33194)

* lisp/filenotify.el (file-notify-callback): Simplify.

2 files changed, 39 insertions, 32 deletions

diff --git a/lisp/autorevert.el b/lisp/autorevert.el
index fc3469e03df..2cf5b427ea3 100644
--- a/lisp/autorevert.el
+++ b/lisp/autorevert.el
@@ -515,32 +515,43 @@ will use an up-to-date value of `auto-revert-interval'"
 
 (defun auto-revert-notify-add-watch ()
   "Enable file notification for current buffer's associated file."
-  ;; We can assume that `buffer-file-name' and
-  ;; `auto-revert-notify-watch-descriptor' are non-nil.
+  ;; We can assume that `auto-revert-notify-watch-descriptor' is nil.
   (unless (or auto-revert-notify-watch-descriptor
               (string-match auto-revert-notify-exclude-dir-regexp
                             (expand-file-name default-directory))
               (file-symlink-p (or buffer-file-name default-directory)))
-    (setq auto-revert-notify-watch-descriptor
-          (ignore-errors
-            (if buffer-file-name
-                (file-notify-add-watch
-                 (expand-file-name buffer-file-name default-directory)
-                 '(change attribute-change)
-                 'auto-revert-notify-handler)
-              (file-notify-add-watch
-               (expand-file-name default-directory)
-               '(change)
-               'auto-revert-notify-handler))))
-    (when auto-revert-notify-watch-descriptor
-      (setq auto-revert-notify-modified-p t)
-      (puthash
-      auto-revert-notify-watch-descriptor
-       (cons (current-buffer)
-             (gethash auto-revert-notify-watch-descriptor
-                      auto-revert-notify-watch-descriptor-hash-list))
+    ;; Check, whether this has been activated already.
+    (let ((file (if buffer-file-name
+                    (expand-file-name buffer-file-name default-directory)
+                  (expand-file-name default-directory))))
+      (maphash
+       (lambda (key _value)
+         (when (and
+                (equal (file-notify--watch-absolute-filename
+                        (gethash key file-notify-descriptors))
+                       (directory-file-name file))
+                (equal (file-notify--watch-callback
+                        (gethash key file-notify-descriptors))
+                       'auto-revert-notify-handler))
+         (setq auto-revert-notify-watch-descriptor key)))
        auto-revert-notify-watch-descriptor-hash-list)
-      (add-hook 'kill-buffer-hook #'auto-revert-notify-rm-watch nil t))))
+      ;; Create a new watch if needed.
+      (unless auto-revert-notify-watch-descriptor
+        (setq auto-revert-notify-watch-descriptor
+              (ignore-errors
+                (file-notify-add-watch
+                 file
+                 (if buffer-file-name '(change attribute-change) '(change))
+                 'auto-revert-notify-handler))))
+      (when auto-revert-notify-watch-descriptor
+        (setq auto-revert-notify-modified-p t)
+        (puthash
+         auto-revert-notify-watch-descriptor
+         (cons (current-buffer)
+               (gethash auto-revert-notify-watch-descriptor
+                        auto-revert-notify-watch-descriptor-hash-list))
+         auto-revert-notify-watch-descriptor-hash-list)
+        (add-hook 'kill-buffer-hook #'auto-revert-notify-rm-watch nil t)))))
 
 ;; If we have file notifications, we want to update the auto-revert buffers
 ;; immediately when a notification occurs. Since file updates can happen very
@@ -626,10 +637,7 @@ no more reverts are possible until the next call of
                           auto-revert-buffers-counter)
                   (auto-revert-handler)
                   (setq auto-revert-buffers-counter-lockedout
-                        auto-revert-buffers-counter))
-
-                ;; No need to check other buffers.
-                (cl-return)))))))))
+                        auto-revert-buffers-counter))))))))))
 
 (defun auto-revert-active-p ()
   "Check if auto-revert is active (in current buffer or globally)."
diff --git a/lisp/filenotify.el b/lisp/filenotify.el
index 59a8c0e88aa..a133f9ea7ec 100644
--- a/lisp/filenotify.el
+++ b/lisp/filenotify.el
@@ -45,11 +45,11 @@ could use another implementation.")
                (:constructor nil)
                (:constructor
                 file-notify--watch-make (directory filename callback)))
-  ;; Watched directory
+  ;; Watched directory.
   directory
   ;; Watched relative filename, nil if watching the directory.
   filename
-  ;; Function to propagate events to
+  ;; Function to propagate events to.
   callback)
 
 (defun file-notify--watch-absolute-filename (watch)
@@ -242,11 +242,10 @@ EVENT is the cadr of the event in `file-notify-handle-event'
             ;;(message
             ;;"file-notify-callback %S %S %S %S %S"
             ;;desc action file file1 watch)
-            (if file1
-                (funcall (file-notify--watch-callback watch)
-                         `(,desc ,action ,file ,file1))
-              (funcall (file-notify--watch-callback watch)
-                       `(,desc  ,action ,file))))
+            (funcall (file-notify--watch-callback watch)
+                     (if file1
+                         `(,desc ,action ,file ,file1)
+                       `(,desc ,action ,file))))
 
           ;; Send `stopped' event.
           (when (or stopped