(inhibit-frame-set-background-mode): New var.

(frame-set-background-mode): Use it to avoid a loop in face-spec-recalc.

diff --git a/lisp/faces.el b/lisp/faces.el
index 97e40e5c5ea446d9e06bb6bbefaa66e4c07ac7d6..269a90972c031991eb2119f4330a462c4db39402 100644 (file)
--- a/lisp/faces.el
+++ b/lisp/faces.el
@@ -1839,82 +1839,88 @@ variable with `setq'; this won't have the expected effect."
 (declare-function x-get-resource "frame.c"
                  (attribute class &optional component subclass))
 
+(defvar inhibit-frame-set-background-mode nil)
+
 (defun frame-set-background-mode (frame)
   "Set up display-dependent faces on FRAME.
 Display-dependent faces are those which have different definitions
 according to the `background-mode' and `display-type' frame parameters."
-  (let* ((bg-resource
-         (and (window-system frame)
-              (x-get-resource "backgroundMode" "BackgroundMode")))
-        (bg-color (frame-parameter frame 'background-color))
-        (terminal-bg-mode (terminal-parameter frame 'background-mode))
-        (tty-type (tty-type frame))
-        (bg-mode
-         (cond (frame-background-mode)
-               (bg-resource
-                (intern (downcase bg-resource)))
-               (terminal-bg-mode)
-               ((and (null (window-system frame))
-                     ;; Unspecified frame background color can only
-                     ;; happen on tty's.
-                     (member bg-color '(nil unspecified "unspecified-bg")))
-                ;; There is no way to determine the background mode
-                ;; automatically, so we make a guess based on the
-                ;; terminal type.
-                (if (and tty-type
-                         (string-match "^\\(xterm\\|rxvt\\|dtterm\\|eterm\\)"
-                                       tty-type))
-                    'light
-                  'dark))
-               ((equal bg-color "unspecified-fg") ; inverted colors
-                (if (and tty-type
-                         (string-match "^\\(xterm\\|rxvt\\|dtterm\\|eterm\\)"
-                                       tty-type))
-                    'dark
-                  'light))
-               ((>= (apply '+ (color-values bg-color frame))
-                   ;; Just looking at the screen, colors whose
-                   ;; values add up to .6 of the white total
-                   ;; still look dark to me.
-                   (* (apply '+ (color-values "white" frame)) .6))
-                'light)
-               (t 'dark)))
-        (display-type
-         (cond ((null (window-system frame))
-                (if (tty-display-color-p frame) 'color 'mono))
-               ((display-color-p frame)
-                'color)
-               ((x-display-grayscale-p frame)
-                'grayscale)
-               (t 'mono)))
-        (old-bg-mode
-         (frame-parameter frame 'background-mode))
-        (old-display-type
-         (frame-parameter frame 'display-type)))
-
-    (unless (and (eq bg-mode old-bg-mode) (eq display-type old-display-type))
-      (let ((locally-modified-faces nil))
-       ;; Before modifying the frame parameters, we collect a list of
-       ;; faces that don't match what their face-spec says they should
-       ;; look like; we then avoid changing these faces below.
-       ;; These are the faces whose attributes were modified on FRAME.
-       ;; We use a negative list on the assumption that most faces will
-       ;; be unmodified, so we can avoid consing in the common case.
-       (dolist (face (face-list))
-         (and (not (get face 'face-override-spec))
-              (not (face-spec-match-p face
-                                      (face-user-default-spec face)
-                                      (selected-frame)))
-              (push face locally-modified-faces)))
-       ;; Now change to the new frame parameters
-       (modify-frame-parameters frame
-                                (list (cons 'background-mode bg-mode)
-                                      (cons 'display-type display-type)))
-       ;; For all named faces, choose face specs matching the new frame
-       ;; parameters, unless they have been locally modified.
-       (dolist (face (face-list))
-         (unless (memq face locally-modified-faces)
-           (face-spec-recalc face frame)))))))
+  (unless inhibit-frame-set-background-mode
+    (let* ((bg-resource
+           (and (window-system frame)
+                (x-get-resource "backgroundMode" "BackgroundMode")))
+          (bg-color (frame-parameter frame 'background-color))
+          (terminal-bg-mode (terminal-parameter frame 'background-mode))
+          (tty-type (tty-type frame))
+          (bg-mode
+           (cond (frame-background-mode)
+                 (bg-resource (intern (downcase bg-resource)))
+                 (terminal-bg-mode)
+                 ((and (null (window-system frame))
+                       ;; Unspecified frame background color can only
+                       ;; happen on tty's.
+                       (member bg-color '(nil unspecified "unspecified-bg")))
+                  ;; There is no way to determine the background mode
+                  ;; automatically, so we make a guess based on the
+                  ;; terminal type.
+                  (if (and tty-type
+                           (string-match "^\\(xterm\\|rxvt\\|dtterm\\|eterm\\)"
+                                         tty-type))
+                      'light
+                    'dark))
+                 ((equal bg-color "unspecified-fg") ; inverted colors
+                  (if (and tty-type
+                           (string-match "^\\(xterm\\|rxvt\\|dtterm\\|eterm\\)"
+                                         tty-type))
+                      'dark
+                    'light))
+                 ((>= (apply '+ (color-values bg-color frame))
+                      ;; Just looking at the screen, colors whose
+                      ;; values add up to .6 of the white total
+                      ;; still look dark to me.
+                      (* (apply '+ (color-values "white" frame)) .6))
+                  'light)
+                 (t 'dark)))
+          (display-type
+           (cond ((null (window-system frame))
+                  (if (tty-display-color-p frame) 'color 'mono))
+                 ((display-color-p frame)
+                  'color)
+                 ((x-display-grayscale-p frame)
+                  'grayscale)
+                 (t 'mono)))
+          (old-bg-mode
+           (frame-parameter frame 'background-mode))
+          (old-display-type
+           (frame-parameter frame 'display-type)))
+
+      (unless (and (eq bg-mode old-bg-mode) (eq display-type old-display-type))
+       (let ((locally-modified-faces nil)
+             ;; Prevent face-spec-recalc from calling this function
+             ;; again, resulting in a loop (bug#911).
+             (inhibit-frame-set-background-mode t))
+         ;; Before modifying the frame parameters, collect a list of
+         ;; faces that don't match what their face-spec says they
+         ;; should look like.  We then avoid changing these faces
+         ;; below.  These are the faces whose attributes were
+         ;; modified on FRAME.  We use a negative list on the
+         ;; assumption that most faces will be unmodified, so we can
+         ;; avoid consing in the common case.
+         (dolist (face (face-list))
+           (and (not (get face 'face-override-spec))
+                (not (face-spec-match-p face
+                                        (face-user-default-spec face)
+                                        (selected-frame)))
+                (push face locally-modified-faces)))
+         ;; Now change to the new frame parameters
+         (modify-frame-parameters frame
+                                  (list (cons 'background-mode bg-mode)
+                                        (cons 'display-type display-type)))
+         ;; For all named faces, choose face specs matching the new frame
+         ;; parameters, unless they have been locally modified.
+         (dolist (face (face-list))
+           (unless (memq face locally-modified-faces)
+             (face-spec-recalc face frame))))))))
 
 \f
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