(gud-filter): Save up text that arrives while processing previous text.

diff --git a/lisp/gud.el b/lisp/gud.el
index 87917045838e59bbf6b91dd2e3d6eb12643de482..787d7e74bc2a14773ccd0ea4fa8be19c9d0617d8 100644 (file)
--- a/lisp/gud.el
+++ b/lisp/gud.el
@@ -1175,6 +1175,13 @@ comint mode, which see."
   (cond ((eq major-mode 'gud-mode)
        (setq gud-comint-buffer (current-buffer)))))
 
+(defvar gud-filter-defer-flag nil
+  "Non-nil means don't process anything from the debugger right now.
+It is saved for when this flag is not set.")
+
+(defvar gud-filter-pending-text nil
+  "Non-nil means this is text that has been saved for later in `gud-filter'.")
+
 ;; These functions are responsible for inserting output from your debugger
 ;; into the buffer.  The hard work is done by the method that is
 ;; the value of gud-marker-filter.
@@ -1183,26 +1190,43 @@ comint mode, which see."
   ;; Here's where the actual buffer insertion is done
   (let (output)
     (if (buffer-name (process-buffer proc))
-       (save-excursion
-         (set-buffer (process-buffer proc))
-         ;; If we have been so requested, delete the debugger prompt.
-         (if (marker-buffer gud-delete-prompt-marker)
-             (progn
-               (delete-region (process-mark proc) gud-delete-prompt-marker)
-               (set-marker gud-delete-prompt-marker nil)))
-         ;; Save the process output, checking for source file markers.
-         (setq output (gud-marker-filter string))
-         ;; Check for a filename-and-line number.
-         ;; Don't display the specified file
-         ;; unless (1) point is at or after the position where output appears
-         ;; and (2) this buffer is on the screen.
-         (if (and gud-last-frame
-                  (>= (point) (process-mark proc))
-                  (get-buffer-window (current-buffer)))
-             (gud-display-frame))
-         ;; Let the comint filter do the actual insertion.
-         ;; That lets us inherit various comint features.
-         (comint-output-filter proc output)))))
+       (if gud-filter-defer-flag
+           ;; If we can't process any text now,
+           ;; save it for later.
+           (setq gud-filter-pending-text
+                 (concat (or gud-filter-pending-text "") string))
+         (save-excursion
+           ;; If we have to ask a question during the processing,
+           ;; defer any additional text that comes from the debugger
+           ;; during that time.
+           (let ((gud-filter-defer-flag t))
+             ;; Process now any text we previously saved up.
+             (if gud-filter-pending-text
+                 (setq string (concat gud-filter-pending-text string)
+                       gud-filter-pending-text nil))
+             (set-buffer (process-buffer proc))
+             ;; If we have been so requested, delete the debugger prompt.
+             (if (marker-buffer gud-delete-prompt-marker)
+                 (progn
+                   (delete-region (process-mark proc) gud-delete-prompt-marker)
+                   (set-marker gud-delete-prompt-marker nil)))
+             ;; Save the process output, checking for source file markers.
+             (setq output (gud-marker-filter string))
+             ;; Check for a filename-and-line number.
+             ;; Don't display the specified file
+             ;; unless (1) point is at or after the position where output appears
+             ;; and (2) this buffer is on the screen.
+             (if (and gud-last-frame
+                      (>= (point) (process-mark proc))
+                      (get-buffer-window (current-buffer)))
+                 (gud-display-frame))
+             ;; Let the comint filter do the actual insertion.
+             ;; That lets us inherit various comint features.
+             (comint-output-filter proc output))
+           ;; If we deferred text that arrived during this processing,
+           ;; handle it now.
+           (if gud-filter-pending-text
+               (gud-filter proc "")))))))
 
 (defun gud-sentinel (proc msg)
   (cond ((null (buffer-name (process-buffer proc)))