(with-local-quit): Return nil if there's a quit.

(read-passwd): Use with-local-quit.  Doc fix.

lisp/subr.el

@@ -1212,51 +1212,59 @@ any other non-digit terminates the character code and is then used as input."))
     code))
 
 (defun read-passwd (prompt &optional confirm default)
-  "Read a password, prompting with PROMPT.  Echo `.' for each character typed.
-End with RET, LFD, or ESC.  DEL or C-h rubs out.  C-u kills line.
-If optional CONFIRM is non-nil, read password twice to make sure.
-Optional DEFAULT is a default password to use instead of empty input."
-  (if confirm
-      (let (success)
-	(while (not success)
-	  (let ((first (read-passwd prompt nil default))
-		(second (read-passwd "Confirm password: " nil default)))
-	    (if (equal first second)
-		(progn
-		  (and (arrayp second) (clear-string second))
-		  (setq success first))
-	      (and (arrayp first) (clear-string first))
-	      (and (arrayp second) (clear-string second))
-	      (message "Password not repeated accurately; please start over")
-	      (sit-for 1))))
-	success)
-    (let ((pass nil)
-	  (c 0)
-	  (echo-keystrokes 0)
-	  (cursor-in-echo-area t))
-      (while (progn (message "%s%s"
-			     prompt
-			     (make-string (length pass) ?.))
-		    (setq c (read-char-exclusive nil t))
-		    (and (/= c ?\r) (/= c ?\n) (/= c ?\e)))
-	(clear-this-command-keys)
-	(if (= c ?\C-u)
-	    (progn
-	      (and (arrayp pass) (clear-string pass))
-	      (setq pass ""))
-	  (if (and (/= c ?\b) (/= c ?\177))
-	      (let* ((new-char (char-to-string c))
-		     (new-pass (concat pass new-char)))
+  "Read a password, prompting with PROMPT, and return it.
+If optional CONFIRM is non-nil, read the password twice to make sure.
+Optional DEFAULT is a default password to use instead of empty input.
+
+This function echoes `.' for each character that the user types.
+The user ends with RET, LFD, or ESC.  DEL or C-h rubs out.  C-u kills line.
+C-g quits; if `inhibit-quit' was non-nil around this function,
+then it returns nil if the user types C-g.
+
+Once the caller uses the password, it can erase the password
+by doing (clear-string STRING)."
+  (with-local-quit
+    (if confirm
+	(let (success)
+	  (while (not success)
+	    (let ((first (read-passwd prompt nil default))
+		  (second (read-passwd "Confirm password: " nil default)))
+	      (if (equal first second)
+		  (progn
+		    (and (arrayp second) (clear-string second))
+		    (setq success first))
+		(and (arrayp first) (clear-string first))
+		(and (arrayp second) (clear-string second))
+		(message "Password not repeated accurately; please start over")
+		(sit-for 1))))
+	  success)
+      (let ((pass nil)
+	    (c 0)
+	    (echo-keystrokes 0)
+	    (cursor-in-echo-area t))
+	(while (progn (message "%s%s"
+			       prompt
+			       (make-string (length pass) ?.))
+		      (setq c (read-char-exclusive nil t))
+		      (and (/= c ?\r) (/= c ?\n) (/= c ?\e)))
+	  (clear-this-command-keys)
+	  (if (= c ?\C-u)
+	      (progn
 		(and (arrayp pass) (clear-string pass))
-		(clear-string new-char)
-		(setq c ?\0)
-		(setq pass new-pass))
-	    (if (> (length pass) 0)
-		(let ((new-pass (substring pass 0 -1)))
+		(setq pass ""))
+	    (if (and (/= c ?\b) (/= c ?\177))
+		(let* ((new-char (char-to-string c))
+		       (new-pass (concat pass new-char)))
 		  (and (arrayp pass) (clear-string pass))
-		  (setq pass new-pass))))))
-      (message nil)
-      (or pass default ""))))
+		  (clear-string new-char)
+		  (setq c ?\0)
+		  (setq pass new-pass))
+	      (if (> (length pass) 0)
+		  (let ((new-pass (substring pass 0 -1)))
+		    (and (arrayp pass) (clear-string pass))
+		    (setq pass new-pass))))))
+	(message nil)
+	(or pass default "")))))
 
 ;; This should be used by `call-interactively' for `n' specs.
 (defun read-number (prompt &optional default)
@@ -1822,14 +1830,14 @@ See also `with-temp-file' and `with-output-to-string'."
 
 (defmacro with-local-quit (&rest body)
   "Execute BODY, allowing quits to terminate BODY but not escape further.
-When a quit terminates BODY, `with-local-quit' requests another quit when
-it finishes.  That quit will be processed in turn, the next time quitting
-is again allowed."
+When a quit terminates BODY, `with-local-quit' returns nil but
+requests another quit.  That quit will be processed, the next time quitting
+is allowed once again."
   (declare (debug t) (indent 0))
   `(condition-case nil
        (let ((inhibit-quit nil))
 	 ,@body)
-     (quit (setq quit-flag t))))
+     (quit (setq quit-flag t) nil)))
 
 (defmacro combine-after-change-calls (&rest body)
   "Execute BODY, but don't call the after-change functions till the end.