From 3ed9a1b0be024523703397b91c1b2ba66d848596 Mon Sep 17 00:00:00 2001
From: Po Lu <luangruo@yahoo.com>
Date: Wed, 21 Sep 2022 19:49:31 +0800
Subject: [PATCH] Fix handling of nil device names

* lisp/frame.el (device-class):
* lisp/term/pgtk-win.el (pgtk-device-class):
* lisp/term/x-win.el (x-device-class): Handle `nil'
correctly.  (bug#57969)
---
 lisp/frame.el         |  1 +
 lisp/term/pgtk-win.el |  1 +
 lisp/term/x-win.el    | 71 ++++++++++++++++++++++---------------------
 3 files changed, 38 insertions(+), 35 deletions(-)

diff --git a/lisp/frame.el b/lisp/frame.el
index 6bedffc358b..1d7784dc769 100644
--- a/lisp/frame.el
+++ b/lisp/frame.el
@@ -2516,6 +2516,7 @@ symbols."
           ((eq frame-type 'pgtk)
            (pgtk-device-class name))
           (t (cond
+              ((not name) nil)
               ((string= name "Virtual core pointer")
                'core-pointer)
               ((string= name "Virtual core keyboard")
diff --git a/lisp/term/pgtk-win.el b/lisp/term/pgtk-win.el
index b93e259d82a..20f15739167 100644
--- a/lisp/term/pgtk-win.el
+++ b/lisp/term/pgtk-win.el
@@ -371,6 +371,7 @@ This uses `icon-map-list' to map icon file names to stock icon names."
   "Return the device class of NAME.
 Users should not call this function; see `device-class' instead."
   (cond
+   ((not name) nil)
    ((string-match-p "XTEST" name) 'test)
    ((string= "Virtual core pointer" name) 'core-pointer)
    ((string= "Virtual core keyboard" name) 'core-keyboard)
diff --git a/lisp/term/x-win.el b/lisp/term/x-win.el
index 38266baa969..9d3e7803650 100644
--- a/lisp/term/x-win.el
+++ b/lisp/term/x-win.el
@@ -1573,41 +1573,42 @@ frames on all displays."
 (defun x-device-class (name)
   "Return the device class of NAME.
 Users should not call this function; see `device-class' instead."
-  (let ((downcased-name (downcase name)))
-    (cond
-     ((string-match-p "XTEST" name) 'test)
-     ((string= "Virtual core pointer" name) 'core-pointer)
-     ((string= "Virtual core keyboard" name) 'core-keyboard)
-     ((string-match-p "eraser" downcased-name) 'eraser)
-     ((string-match-p " pad" downcased-name) 'pad)
-     ((or (or (string-match-p "wacom" downcased-name)
-              (string-match-p "pen" downcased-name))
-          (string-match-p "stylus" downcased-name))
-      'pen)
-     ((or (string-prefix-p "xwayland-touch:" name)
-          (string-match-p "touchscreen" downcased-name))
-      'touchscreen)
-     ((or (string-match-p "trackpoint" downcased-name)
-          (string-match-p "stick" downcased-name))
-      'trackpoint)
-     ((or (string-match-p "mouse" downcased-name)
-          (string-match-p "optical" downcased-name)
-          (string-match-p "pointer" downcased-name))
-      'mouse)
-     ((string-match-p "cursor" downcased-name) 'puck)
-     ((or (string-match-p "keyboard" downcased-name)
-          ;; One of my cheap keyboards is really named this...
-          (string= name "USB USB Keykoard"))
-      'keyboard)
-     ((string-match-p "button" downcased-name) 'power-button)
-     ((string-match-p "touchpad" downcased-name) 'touchpad)
-     ((or (string-match-p "midi" downcased-name)
-          (string-match-p "piano" downcased-name))
-      'piano)
-     ((or (string-match-p "wskbd" downcased-name) ; NetBSD/OpenBSD
-          (and (string-match-p "/dev" downcased-name)
-               (string-match-p "kbd" downcased-name)))
-      'keyboard))))
+  (and name
+       (let ((downcased-name (downcase name)))
+         (cond
+          ((string-match-p "XTEST" name) 'test)
+          ((string= "Virtual core pointer" name) 'core-pointer)
+          ((string= "Virtual core keyboard" name) 'core-keyboard)
+          ((string-match-p "eraser" downcased-name) 'eraser)
+          ((string-match-p " pad" downcased-name) 'pad)
+          ((or (or (string-match-p "wacom" downcased-name)
+                   (string-match-p "pen" downcased-name))
+               (string-match-p "stylus" downcased-name))
+           'pen)
+          ((or (string-prefix-p "xwayland-touch:" name)
+               (string-match-p "touchscreen" downcased-name))
+           'touchscreen)
+          ((or (string-match-p "trackpoint" downcased-name)
+               (string-match-p "stick" downcased-name))
+           'trackpoint)
+          ((or (string-match-p "mouse" downcased-name)
+               (string-match-p "optical" downcased-name)
+               (string-match-p "pointer" downcased-name))
+           'mouse)
+          ((string-match-p "cursor" downcased-name) 'puck)
+          ((or (string-match-p "keyboard" downcased-name)
+               ;; One of my cheap keyboards is really named this...
+               (string= name "USB USB Keykoard"))
+           'keyboard)
+          ((string-match-p "button" downcased-name) 'power-button)
+          ((string-match-p "touchpad" downcased-name) 'touchpad)
+          ((or (string-match-p "midi" downcased-name)
+               (string-match-p "piano" downcased-name))
+           'piano)
+          ((or (string-match-p "wskbd" downcased-name) ; NetBSD/OpenBSD
+               (and (string-match-p "/dev" downcased-name)
+                    (string-match-p "kbd" downcased-name)))
+           'keyboard)))))
 
 (setq x-dnd-movement-function #'x-dnd-movement)
 (setq x-dnd-unsupported-drop-function #'x-dnd-handle-unsupported-drop)
-- 
2.39.2