Passthrough input when explicitly reading events and keys

When any of these functions are called, Emacs expects to receive all
input events until they return. Unfortunately, there doesn't appear to
be a reliable way to detect that these functions are currently running
other than advising them.

* exwm-input.el (exwm-input--init): Advise low-level input reading
functions to bind 'exwm-input-line-mode-passthrough' to t when called.
(exwm-input--exit): Unadvise.
(exwm-input--call-with-passthrough): The advice.
(exwm-input--passthrough-functions): The functions we now advise.

1 files changed, 18 insertions, 1 deletions

diff --git a/exwm-input.el b/exwm-input.el
index 05b021093c..7ffd80f38a 100644
--- a/exwm-input.el
+++ b/exwm-input.el
@@ -102,6 +102,13 @@ defined in `exwm-mode-map' here."
 (defconst exwm-input--update-focus-interval 0.01
   "Time interval (in seconds) for accumulating input focus update requests.")
 
+(defconst exwm-input--passthrough-functions '(read-char
+                                              read-char-exclusive
+                                              read-key-sequence-vector
+                                              read-key-sequence
+                                              read-event)
+  "Low-level functions that read events and need to be exempted from EXWM's input handling.")
+
 (defvar exwm-input--during-command nil
   "Indicate whether between `pre-command-hook' and `post-command-hook'.")
 
@@ -1158,6 +1165,11 @@ One use is to access the keymap bound to KEYS (as prefix keys) in `char-mode'."
     (exwm--log)
     (exwm-input--on-minibuffer-exit)))
 
+(defun exwm-input--call-with-passthrough (function &rest args)
+  "Bind `exwm-input-line-mode-passthrough' and call the specified FUNCTION with ARGS."
+  (let ((exwm-input-line-mode-passthrough t))
+    (apply function args)))
+
 (defun exwm-input--init ()
   "Initialize the keyboard module."
   (exwm--log)
@@ -1213,7 +1225,10 @@ One use is to access the keymap bound to KEYS (as prefix keys) in `char-mode'."
         (run-with-idle-timer 0 t #'exwm-input--on-echo-area-dirty))
   (add-hook 'echo-area-clear-hook #'exwm-input--on-echo-area-clear)
   ;; Update focus when buffer list updates
-  (add-hook 'buffer-list-update-hook #'exwm-input--on-buffer-list-update))
+  (add-hook 'buffer-list-update-hook #'exwm-input--on-buffer-list-update)
+
+  (dolist (fun exwm-input--passthrough-functions)
+    (advice-add fun :around #'exwm-input--call-with-passthrough)))
 
 (defun exwm-input--post-init ()
   "The second stage in the initialization of the input module."
@@ -1223,6 +1238,8 @@ One use is to access the keymap bound to KEYS (as prefix keys) in `char-mode'."
 (defun exwm-input--exit ()
   "Exit the input module."
   (exwm--log)
+  (dolist (fun exwm-input--passthrough-functions)
+    (advice-remove fun #'exwm-input--call-with-passthrough))
   (exwm-input--unset-simulation-keys)
   (remove-hook 'pre-command-hook #'exwm-input--on-pre-command)
   (remove-hook 'post-command-hook #'exwm-input--on-post-command)