bug#71223: 30.0.50; stack overflow after very fast opening and closing of frames

[Eli Zaretskii]

> Cc: 71223@debbugs.gnu.org
> Date: Mon, 27 May 2024 15:23:01 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> 
> Does the patch below help?

Actually, the more thorough patch below should be better.  Can you see
if it solves the problems with "Lisp nesting exceeds
`max-lisp-eval-depth'"?

Stefan, any comments about the problem and the proposed solution?

diff --git a/lisp/server.el b/lisp/server.el
index b650532..fcaf0ab 100644
--- a/lisp/server.el
+++ b/lisp/server.el
@@ -1034,6 +1034,15 @@ server-goto-toplevel
     (run-with-timer 0 nil (lambda () (server-execute-continuation proc)))
     (top-level)))
 
+(defun server--sit-for (proc seconds)
+  "Like `sit-for', but disable filter of process PROC and don't redisplay."
+  (let ((orig-filter (process-filter proc)))
+    (unwind-protect
+        (progn
+          (set-process-filter proc nil)
+          (sit-for seconds t))
+      (set-process-filter proc orig-filter))))
+
 ;; We use various special properties on process objects:
 ;; - `env' stores the info about the environment of the emacsclient process.
 ;; - `continuation' is a no-arg function that we need to execute.  It contains
@@ -1159,7 +1168,7 @@ server-process-filter
       ;; it, in case the error written by emacsclient to stderr is not
       ;; visible for some reason.
       (message "Authentication failed")
-      (sit-for 2)
+      (server--sit-for proc 2)
       (server-send-string
        proc (concat "-error " (server-quote-arg "Authentication failed")))
       (unless (eq system-type 'windows-nt)
@@ -1169,7 +1178,7 @@ server-process-filter
            (delete-terminal terminal))))
       ;; Before calling `delete-process', give emacsclient time to
       ;; receive the error string and shut down on its own.
-      (sit-for 1)
+      (server--sit-for proc 1)
       (delete-process proc)
       ;; We return immediately.
       (cl-return-from server-process-filter)))
@@ -1508,7 +1517,7 @@ server-return-error
     ;; it, in case the error written by emacsclient to stderr is not
     ;; visible for some reason.
     (message (error-message-string err))
-    (sit-for 2)
+    (server--sit-for proc 2)
     (server-send-string
      proc (concat "-error " (server-quote-arg
                              (error-message-string err))))
@@ -1520,7 +1529,7 @@ server-return-error
          (delete-terminal terminal))))
     ;; Before calling `delete-process', give emacsclient time to
     ;; receive the error string and shut down on its own.
-    (sit-for 5)
+    (server--sit-for proc 5)
     (delete-process proc)))
 
 (defun server-goto-line-column (line-col)