Make X windows container-less

; This is an attempt to make (managed) X windows container-less, i.e. direct children of the root window.  This is mainly to make EXWM compatible with third-party compositors.  Other issues like wrong absolute position should also get resolved by the way.  The workspace containers ("virtual roots") are also removed.  However Emacs frames are still wrapped in containers to avoid unexpected stack reordering.

* exwm-cm.el: Make this module obsolete as EXWM supports third-party compositors now.

* exwm-core.el (exwm--container):
* exwm-floating.el (exwm-floating--set-floating)
(exwm-floating--unset-floating, exwm-floating-hide)
(exwm-floating--start-moveresize, exwm-floating--stop-moveresize)
(exwm-floating--do-moveresize, exwm-floating-move):
* exwm-input.el (exwm-input--update-focus):
* exwm-layout.el (exwm-layout--show, exwm-layout--hide)
(exwm-layout-set-fullscreen, exwm-layout-unset-fullscreen):
* exwm-manage.el (exwm-manage--manage-window, exwm-manage--unmanage-window)
(exwm-manage--kill-buffer-query-function, exwm-manage--kill-client):
* exwm-workspace.el (exwm-workspace--set-fullscreen, exwm-workspace-switch)
(exwm-workspace-move-window, exwm-workspace--add-frame-as-workspace)
(exwm-workspace--remove-frame-as-workspace): Make adaptions for container-less X windows.

* exwm-workspace.el (exwm-workspace--update-ewmh-props):
* exwm.el (exwm--init-icccm-ewmh, exwm--exit-icccm-ewmh): No longer use virtual roots.

* exwm-input.el (exwm-input--on-workspace-list-change)
(exwm-input--update-global-prefix-keys, exwm-input--init, exwm-input--exit): From now on global key bindings are grabbed on the root window so it's no long required to re-grab them each time the workspace list changes.  As a result `exwm-input--on-workspace-list-change' and its corresponding references are discarded.  It remains to be seen if this change will raise input focus issues.

* exwm-manage.el (exwm-manage--manage-window): Explicitly set the workspace for newly managed X windows.
* exwm-floating.el (exwm-floating--set-floating): Avoid implicit reference to the current workspace.

* exwm-core.el (exwm--set-geometry): New function for setting the geometry of an X window.
* exwm-layout.el (exwm-layout--resize-container): Replaced by `exwm-layout--resize-container'.

* exwm-core.el (exwm--guide-window): New global variable recording the guide X window.
* exwm.el (exwm--init-icccm-ewmh): Set it.

* exwm-input.el (exwm-input--post-init): New function containing staffs for initialization but should better get called after the event loop starts.
* exwm.el (exwm-init): Use it.

1 files changed, 91 insertions, 167 deletions

diff --git a/exwm-floating.el b/exwm-floating.el
index a695346cb2..b0afc1dad3 100644
--- a/exwm-floating.el
+++ b/exwm-floating.el
@@ -75,12 +75,11 @@ context of the corresponding buffer.")
                                      xcb:Atom:_NET_WM_ACTION_CLOSE)))))
 
 (defvar exwm-workspace--current)
-(defvar exwm-workspace--struts)
 (defvar exwm-workspace--workareas)
-(defvar exwm-workspace-current-index)
 
 (declare-function exwm-layout--refresh "exwm-layout.el" ())
 (declare-function exwm-layout--show "exwm-layout.el" (id &optional window))
+(declare-function exwm-layout--hide "exwm-layout.el" (id))
 (declare-function exwm-layout--iconic-state-p "exwm-layout.el" (&optional id))
 (declare-function exwm-workspace--minibuffer-own-frame-p "exwm-workspace.el")
 (declare-function exwm-workspace--position "exwm-workspace.el" (frame))
@@ -91,7 +90,8 @@ context of the corresponding buffer.")
     (when window
       ;; Hide the non-floating X window first.
       (set-window-buffer window (other-buffer nil t))))
-  (let* ((original-frame exwm-workspace--current)
+  (let* ((original-frame (buffer-local-value 'exwm--frame
+                                             (exwm--id->buffer id)))
          ;; Create new frame
          (frame (with-current-buffer
                     (or (get-buffer "*scratch*")
@@ -100,16 +100,14 @@ context of the corresponding buffer.")
                            (get-buffer-create "*scratch*"))
                           (get-buffer "*scratch*")))
                   (make-frame
-                   `((minibuffer . nil) ;use the default minibuffer.
-                     (left . 10000)
-                     (top . 10000)
+                   `((minibuffer . ,(minibuffer-window exwm--frame))
+                     (left . ,(* window-min-width -100))
+                     (top . ,(* window-min-height -100))
                      (width . ,window-min-width)
                      (height . ,window-min-height)
                      (unsplittable . t))))) ;and fix the size later
          (outer-id (string-to-number (frame-parameter frame 'outer-window-id)))
          (window-id (string-to-number (frame-parameter frame 'window-id)))
-         (container (buffer-local-value 'exwm--container
-                                        (exwm--id->buffer id)))
          (frame-container (xcb:generate-id exwm--connection))
          (window (frame-first-window frame)) ;and it's the only window
          (x (slot-value exwm--geometry 'x))
@@ -176,6 +174,8 @@ context of the corresponding buffer.")
             ;; Put at the center of screen
             (setq x (/ (- display-width width) 2)
                   y (/ (- display-height height) 2))))))
+    (exwm--set-geometry id x y nil nil)
+    (xcb:flush exwm--connection)
     (exwm--log "Floating geometry (corrected): %dx%d%+d%+d" width height x y)
     ;; Fit frame to client
     ;; It seems we have to make the frame invisible in order to resize it
@@ -194,61 +194,55 @@ context of the corresponding buffer.")
               exwm--mode-line-format mode-line-format
               mode-line-format nil))
       (set-frame-size frame frame-width frame-height t)
-      ;; Create the frame container as the parent of the frame and
-      ;; a child of the X window container.
+      ;; Create the frame container as the parent of the frame.
       (xcb:+request exwm--connection
           (make-instance 'xcb:CreateWindow
                          :depth 0
                          :wid frame-container
-                         :parent container
-                         :x 0
-                         :y 0
+                         :parent exwm--root
+                         :x (- x (elt edges 0))
+                         :y (- y (elt edges 1))
                          :width width
                          :height height
-                         :border-width 0
+                         :border-width exwm-floating-border-width
                          :class xcb:WindowClass:InputOutput
                          :visual 0
                          :value-mask (logior xcb:CW:BackPixmap
-                                             xcb:CW:OverrideRedirect)
+                                             (if exwm-floating--border-pixel
+                                                 xcb:CW:BorderPixel 0)
+                                             xcb:CW:OverrideRedirect
+                                             (if exwm-floating--border-colormap
+                                                 xcb:CW:Colormap 0))
                          :background-pixmap xcb:BackPixmap:ParentRelative
-                         :override-redirect 1))
-      ;; Put it at bottom.
-      (xcb:+request exwm--connection
-          (make-instance 'xcb:ConfigureWindow
-                         :window frame-container
-                         :value-mask xcb:ConfigWindow:StackMode
-                         :stack-mode xcb:StackMode:Below))
-      ;; Map it.
-      (xcb:+request exwm--connection
-          (make-instance 'xcb:MapWindow :window frame-container))
+                         :border-pixel exwm-floating--border-pixel
+                         :override-redirect 1
+                         :colormap exwm-floating--border-colormap))
       (exwm--debug
        (xcb:+request exwm--connection
            (make-instance 'xcb:ewmh:set-_NET_WM_NAME
                           :window frame-container
                           :data
-                          (format "floating frame container for 0x%x" id)))))
+                          (format "floating frame container for 0x%x" id))))
+      ;; Map it.
+      (xcb:+request exwm--connection
+          (make-instance 'xcb:MapWindow :window frame-container))
+      ;; Put the X window right above this frame container.
+      (xcb:+request exwm--connection
+          (make-instance 'xcb:ConfigureWindow
+                         :window id
+                         :value-mask (logior xcb:ConfigWindow:Sibling
+                                             xcb:ConfigWindow:StackMode)
+                         :sibling frame-container
+                         :stack-mode xcb:StackMode:Above)))
     ;; Reparent this frame to its container.
     (xcb:+request exwm--connection
         (make-instance 'xcb:ReparentWindow
                        :window outer-id :parent frame-container :x 0 :y 0))
-    ;; Place the X window container.
-    ;; Also show the floating border.
-    (xcb:+request exwm--connection
-        (make-instance 'xcb:ConfigureWindow
-                       :window container
-                       :value-mask (eval-when-compile
-                                     (logior xcb:ConfigWindow:X
-                                             xcb:ConfigWindow:Y
-                                             xcb:ConfigWindow:BorderWidth))
-                       :x x
-                       :y y
-                       :border-width exwm-floating-border-width))
     (exwm-floating--set-allowed-actions id nil)
     (xcb:flush exwm--connection)
     ;; Set window/buffer
     (with-current-buffer (exwm--id->buffer id)
       (setq window-size-fixed exwm--fixed-size
-            exwm--frame original-frame
             exwm--floating-frame frame)
       ;; Do the refresh manually.
       (remove-hook 'window-configuration-change-hook #'exwm-layout--refresh)
@@ -256,24 +250,19 @@ context of the corresponding buffer.")
       (add-hook 'window-configuration-change-hook #'exwm-layout--refresh)
       (set-window-dedicated-p window t)
       (exwm-layout--show id window))
-    (if (exwm-layout--iconic-state-p id)
-        ;; Hide iconic floating X windows.
-        (with-current-buffer (exwm--id->buffer id)
-          (exwm-floating-hide))
-      (with-selected-frame exwm-workspace--current
-        (exwm-layout--refresh))
+    (with-current-buffer (exwm--id->buffer id)
+      (if (exwm-layout--iconic-state-p id)
+          ;; Hide iconic floating X windows.
+          (exwm-floating-hide)
+        (with-selected-frame exwm--frame
+          (exwm-layout--refresh)))
       (select-frame-set-input-focus frame))
     ;; FIXME: Strangely, the Emacs frame can move itself at this point
     ;;        when there are left/top struts set.  Force resetting its
     ;;        position seems working, but it'd better to figure out why.
     ;; FIXME: This also happens in another case (#220) where the cause is
     ;;        still unclear.
-    (xcb:+request exwm--connection
-        (make-instance 'xcb:ConfigureWindow
-                       :window outer-id
-                       :value-mask (logior xcb:ConfigWindow:X
-                                           xcb:ConfigWindow:Y)
-                       :x 0 :y 0))
+    (exwm--set-geometry outer-id 0 0 nil nil)
     (xcb:flush exwm--connection))
   (with-current-buffer (exwm--id->buffer id)
     (run-hooks 'exwm-floating-setup-hook))
@@ -286,10 +275,6 @@ context of the corresponding buffer.")
     (with-current-buffer buffer
       (when exwm--floating-frame
         ;; The X window is already mapped.
-        ;; Unmap the container to prevent flickering.
-        (xcb:+request exwm--connection
-            (make-instance 'xcb:UnmapWindow :window exwm--container))
-        (xcb:flush exwm--connection)
         ;; Unmap the X window.
         (xcb:+request exwm--connection
             (make-instance 'xcb:ChangeWindowAttributes
@@ -315,29 +300,30 @@ context of the corresponding buffer.")
           ;; Also destroy its container.
           (xcb:+request exwm--connection
               (make-instance 'xcb:DestroyWindow :window frame-container))))
-      ;; Put the X window container just above the Emacs frame container
+      ;; Place the X window just above the reference X window.
       ;; (the stacking order won't change from now on).
       ;; Also hide the possible floating border.
       (xcb:+request exwm--connection
           (make-instance 'xcb:ConfigureWindow
-                         :window exwm--container
+                         :window id
                          :value-mask (logior xcb:ConfigWindow:BorderWidth
                                              xcb:ConfigWindow:Sibling
                                              xcb:ConfigWindow:StackMode)
                          :border-width 0
-                         :sibling (frame-parameter exwm-workspace--current
-                                                   'exwm-container)
+                         :sibling exwm--guide-window
                          :stack-mode xcb:StackMode:Above)))
     (exwm-floating--set-allowed-actions id t)
     (xcb:flush exwm--connection)
     (with-current-buffer buffer
       (when exwm--floating-frame        ;from floating to non-floating
         (set-window-dedicated-p (frame-first-window exwm--floating-frame) nil)
-        (delete-frame exwm--floating-frame))) ;remove the floating frame
+        ;; Select a tiling window and delete the old frame.
+        (select-window (frame-selected-window exwm-workspace--current))
+        (with-current-buffer buffer
+          (delete-frame exwm--floating-frame))))
     (with-current-buffer buffer
       (setq window-size-fixed nil
-            exwm--floating-frame nil
-            exwm--frame exwm-workspace--current))
+            exwm--floating-frame nil))
     ;; Only show X windows in normal state.
     (unless (exwm-layout--iconic-state-p)
       (pop-to-buffer-same-window buffer)))
@@ -361,14 +347,7 @@ context of the corresponding buffer.")
   (interactive)
   (when (and (eq major-mode 'exwm-mode)
              exwm--floating-frame)
-    ;; Put this floating X window at bottom.
-    (xcb:+request exwm--connection
-        (make-instance 'xcb:ConfigureWindow
-                       :window exwm--container
-                       :value-mask xcb:ConfigWindow:StackMode
-                       :stack-mode xcb:StackMode:Below))
-    (exwm-layout--set-state exwm--id xcb:icccm:WM_STATE:IconicState)
-    (xcb:flush exwm--connection)
+    (exwm-layout--hide exwm--id)
     (select-frame-set-input-focus exwm-workspace--current)))
 
 (define-obsolete-function-alias 'exwm-floating-hide-mode-line
@@ -387,7 +366,8 @@ context of the corresponding buffer.")
         ;; Managed.
         (with-current-buffer buffer-or-id
           (setq frame exwm--floating-frame
-                container-or-id exwm--container))
+                container-or-id (frame-parameter exwm--floating-frame
+                                                 'exwm-container)))
       ;; Unmanaged.
       (setq container-or-id id))
     (when (and container-or-id
@@ -545,96 +525,58 @@ context of the corresponding buffer.")
   "Stop move/resize."
   (xcb:+request exwm--connection
       (make-instance 'xcb:UngrabPointer :time xcb:Time:CurrentTime))
-  ;; Inform the X window that its absolute position is changed
-  (when (and exwm-floating--moveresize-calculate
-             ;; Unmanaged.
-             (eq major-mode 'exwm-mode))
-    (let ((edges (window-inside-absolute-pixel-edges (frame-selected-window)))
-          x y width height id)
-      (setq x (pop edges)
-            y (pop edges)
-            width (- (pop edges) x)
-            height (- (pop edges) y))
-      (with-current-buffer (window-buffer (frame-selected-window))
-        (setq id exwm--id)
-        (with-slots ((x* x)
-                     (y* y)
-                     (width* width)
-                     (height* height))
-            exwm--geometry
-          (setf x* x
-                y* y
-                width* width
-                height* height)))
-      (xcb:+request exwm--connection
-          (make-instance 'xcb:SendEvent
-                         :propagate 0
-                         :destination id
-                         :event-mask xcb:EventMask:StructureNotify
-                         :event (xcb:marshal
-                                 (make-instance 'xcb:ConfigureNotify
-                                                :event id :window id
-                                                :above-sibling xcb:Window:None
-                                                :x x
-                                                :y y
-                                                :width width
-                                                :height height
-                                                :border-width 0
-                                                :override-redirect 0)
-                                 exwm--connection)))))
-  (xcb:flush exwm--connection)
-  (setq exwm-floating--moveresize-calculate nil))
+  (when exwm-floating--moveresize-calculate
+    (let (result buffer-or-id)
+      (setq result (funcall exwm-floating--moveresize-calculate 0 0)
+            buffer-or-id (aref result 0))
+      (when (bufferp buffer-or-id)
+        (with-current-buffer buffer-or-id
+          (exwm-layout--show exwm--id
+                             (frame-root-window exwm--floating-frame)))))
+    (setq exwm-floating--moveresize-calculate nil)))
 
 (defun exwm-floating--do-moveresize (data _synthetic)
   "Perform move/resize."
   (when exwm-floating--moveresize-calculate
     (let* ((obj (make-instance 'xcb:MotionNotify))
-           (workarea (elt exwm-workspace--workareas
-                          exwm-workspace-current-index))
-           (frame-x (aref workarea 0))
-           (frame-y (aref workarea 1))
-           result value-mask width height buffer-or-id container-or-id)
+           result value-mask x y width height buffer-or-id container-or-id)
       (xcb:unmarshal obj data)
       (setq result (funcall exwm-floating--moveresize-calculate
                             (slot-value obj 'root-x) (slot-value obj 'root-y))
-            value-mask (logand (aref result 1)
-                               (eval-when-compile
-                                 (logior xcb:ConfigWindow:Width
-                                         xcb:ConfigWindow:Height)))
+            buffer-or-id (aref result 0)
+            value-mask (aref result 1)
+            x (aref result 2)
+            y (aref result 3)
             width (max 1 (aref result 4))
             height (max 1 (aref result 5)))
-      (setq buffer-or-id (aref result 0))
       (setq container-or-id
             (if (bufferp buffer-or-id)
                 ;; Managed.
-                (buffer-local-value 'exwm--container buffer-or-id)
+                (with-current-buffer buffer-or-id
+                  (frame-parameter exwm--floating-frame 'exwm-container))
               ;; Unmanaged.
               buffer-or-id))
       (xcb:+request exwm--connection
           (make-instance 'xcb:ConfigureWindow
                          :window container-or-id
                          :value-mask (aref result 1)
-                         :x (- (aref result 2) frame-x)
-                         :y (- (aref result 3) frame-y)
+                         :x x
+                         :y y
                          :width width
                          :height height))
       (when (bufferp buffer-or-id)
         ;; Managed.
-        (with-current-buffer buffer-or-id
-          (xcb:+request exwm--connection
-              (make-instance 'xcb:ConfigureWindow
-                             :window (frame-parameter exwm--floating-frame
-                                                      'exwm-container)
-                             :value-mask value-mask
-                             :width width
-                             :height height))
-          (xcb:+request exwm--connection
-              (make-instance 'xcb:ConfigureWindow
-                             :window (frame-parameter exwm--floating-frame
-                                                      'exwm-outer-id)
-                             :value-mask value-mask
-                             :width width
-                             :height height))))
+        (setq value-mask (logand value-mask (logior xcb:ConfigWindow:Width
+                                                    xcb:ConfigWindow:Height)))
+        (when (/= 0 value-mask)
+          (with-current-buffer buffer-or-id
+            (xcb:+request exwm--connection
+                (make-instance 'xcb:ConfigureWindow
+                               :window (frame-parameter exwm--floating-frame
+                                                        'exwm-outer-id)
+                               :value-mask value-mask
+                               :width width
+                               :height height)))))
       (xcb:flush exwm--connection))))
 
 (defun exwm-floating-move (&optional delta-x delta-y)
@@ -646,37 +588,19 @@ Both DELTA-X and DELTA-Y default to 1.  This command should be bound locally."
   (unless delta-x (setq delta-x 1))
   (unless delta-y (setq delta-y 1))
   (unless (and (= 0 delta-x) (= 0 delta-y))
-    (let* ((geometry (xcb:+request-unchecked+reply exwm--connection
+    (let* ((floating-container (frame-parameter exwm--floating-frame
+                                                'exwm-container))
+           (geometry (xcb:+request-unchecked+reply exwm--connection
                          (make-instance 'xcb:GetGeometry
-                                        :drawable exwm--container)))
+                                        :drawable floating-container)))
            (edges (window-inside-absolute-pixel-edges)))
-      (xcb:+request exwm--connection
-          (make-instance 'xcb:ConfigureWindow
-                         :window exwm--container
-                         :value-mask (eval-when-compile
-                                       (logior xcb:ConfigWindow:X
-                                               xcb:ConfigWindow:Y))
-                         :x (+ (slot-value geometry 'x) delta-x)
-                         :y (+ (slot-value geometry 'y) delta-y)))
-      ;; Inform the X window that its absolute position is changed
-      (xcb:+request exwm--connection
-          (make-instance 'xcb:SendEvent
-                         :propagate 0 :destination exwm--id
-                         :event-mask xcb:EventMask:StructureNotify
-                         :event (xcb:marshal
-                                 (make-instance 'xcb:ConfigureNotify
-                                                :event exwm--id
-                                                :window exwm--id
-                                                :above-sibling xcb:Window:None
-                                                :x (+ (elt edges 0) delta-x)
-                                                :y (+ (elt edges 1) delta-y)
-                                                :width (- (elt edges 2)
-                                                          (elt edges 0))
-                                                :height (- (elt edges 3)
-                                                           (elt edges 1))
-                                                :border-width 0
-                                                :override-redirect 0)
-                                 exwm--connection))))
+      (with-slots (x y) geometry
+        (exwm--set-geometry floating-container
+                            (+ x delta-x) (+ y delta-y) nil nil))
+      (exwm--set-geometry exwm--id
+                          (+ (pop edges) delta-x)
+                          (+ (pop edges) delta-y)
+                          nil nil))
     (xcb:flush exwm--connection)))
 
 (defun exwm-floating--init ()