(enable-flow-control): Use a char-table.

diff --git a/lisp/flow-ctrl.el b/lisp/flow-ctrl.el
index c853ae3a767d53a9b71ab0fec53ae98b884ea59d..4bad32a0c110e1195a60e857017cee9f456cb703 100644 (file)
--- a/lisp/flow-ctrl.el
+++ b/lisp/flow-ctrl.el
@@ -48,6 +48,8 @@
 (defvar flow-control-c-q-replacement ?\036
   "Character that replaces C-q, when flow control handling is enabled.")
 
+(put 'keyboard-translate-table 'char-table-extra-slots 0)
+
 ;;;###autoload
 (defun enable-flow-control (&optional argument)
   "Toggle flow control handling.
@@ -64,27 +66,28 @@ With arg, enable flow control mode if arg is positive, otherwise disable."
        (set-input-mode t nil (nth 2 (current-input-mode)))
        (if keyboard-translate-table
            (progn
-             (aset keyboard-translate-table flow-control-c-s-replacement
-                   flow-control-c-s-replacement)
-             (aset keyboard-translate-table ?\^s ?\^s)
-             (aset keyboard-translate-table flow-control-c-q-replacement
-                   flow-control-c-q-replacement)
-             (aset keyboard-translate-table ?\^q ?\^q))))
+             (aset keyboard-translate-table flow-control-c-s-replacement nil)
+             (aset keyboard-translate-table ?\^s nil)
+             (aset keyboard-translate-table flow-control-c-q-replacement nil)
+             (aset keyboard-translate-table ?\^q nil))))
     ;; Turn flow control on.
     ;; Tell emacs to pass C-s and C-q to OS.
     (set-input-mode nil t (nth 2 (current-input-mode)))
     ;; Initialize translate table, saving previous mappings, if any.
-    (let ((the-table (make-string (max 128 (length keyboard-translate-table))
-                                 0)))
-      (let ((i 0)
-           (j (length keyboard-translate-table)))
-       (while (< i j)
-         (aset the-table i (elt keyboard-translate-table i))
-         (setq i (1+ i)))
-       (while (< i 128)
-         (aset the-table i i)
-         (setq i (1+ i))))
-      (setq keyboard-translate-table the-table))
+    (cond ((null keyboard-translate-table)
+          (setq keyboard-translate-table
+                (make-char-table 'keyboard-translate-table nil)))
+         ((char-table-p keyboard-translate-table)
+          (setq keyboard-translate-table
+                (copy-sequence keyboard-translate-table)))
+         (t
+          (let ((the-table (make-char-table 'keyboard-translate-table nil)))
+            (let ((i 0)
+                  (j (length keyboard-translate-table)))
+              (while (< i j)
+                (aset the-table i (elt keyboard-translate-table i))
+                (setq i (1+ i))))
+            (setq keyboard-translate-table the-table))))
     ;; Swap C-s and C-\
     (aset keyboard-translate-table flow-control-c-s-replacement ?\^s)
     (aset keyboard-translate-table ?\^s flow-control-c-s-replacement)