Don't use BLOCK-THREAD-EVENTS to prevent the previewer from running --

there's a window in which an event can be delivered, causing a
character to be queued; but READ-EVENT doesn't look at the queue after
it's in that state.

diff --git a/v7/src/edwin/xterm.scm b/v7/src/edwin/xterm.scm
index 81876db23d114a1b5b8604e375812a371d794963..76708d3c1d3623567cf388f1b554c7200255645a 100644 (file)
--- a/v7/src/edwin/xterm.scm
+++ b/v7/src/edwin/xterm.scm
@@ -1,6 +1,6 @@
 ;;; -*-Scheme-*-
 ;;;
-;;;    $Id: xterm.scm,v 1.38 1993/04/27 09:22:32 cph Exp $
+;;;    $Id: xterm.scm,v 1.39 1993/04/28 19:51:10 cph Exp $
 ;;;
 ;;;    Copyright (c) 1989-93 Massachusetts Institute of Technology
 ;;;
@@ -415,17 +415,14 @@
 \f
 (define (read-event queue display block?)
   (let loop ()
+    (set! reading-event? #t)
     (let ((event
-          (let ((block-events? (block-thread-events)))
-            (let ((event
-                   (if (queue-empty? queue)
-                       (if (eq? 'IN-UPDATE block?)
-                           (x-display-process-events display 2)
-                           (read-event-1 display block?))
-                       (dequeue!/unsafe queue))))
-              (if (not block-events?)
-                  (unblock-thread-events))
-              event))))
+          (if (queue-empty? queue)
+              (if (eq? 'IN-UPDATE block?)
+                  (x-display-process-events display 2)
+                  (read-event-1 display block?))
+              (dequeue!/unsafe queue))))
+      (set! reading-event? #f)
       (if (and (vector? event)
               (fix:= (vector-ref event 0) event-type:expose))
          (begin
@@ -457,15 +454,17 @@
         (x-display-descriptor x-display-data)
         (current-thread)
         (lambda ()
-          (let ((event (x-display-process-events x-display-data 2)))
-            (if event
-                (if (and signal-interrupts?
-                         (fix:= event-type:key-press (vector-ref event 0))
-                         (string-find-next-char (vector-ref event 2) #\BEL))
-                    (begin
-                      (clean-event-queue x-display-events)
-                      (signal-interrupt!))
-                    (enqueue!/unsafe x-display-events event)))))))
+          (if (not reading-event?)
+              (let ((event (x-display-process-events x-display-data 2)))
+                (if event
+                    (if (and signal-interrupts?
+                             (fix:= event-type:key-press (vector-ref event 0))
+                             (string-find-next-char (vector-ref event 2)
+                                                    #\BEL))
+                        (begin
+                          (clean-event-queue x-display-events)
+                          (signal-interrupt!))
+                        (enqueue!/unsafe x-display-events event))))))))
   unspecific)
 \f
 (define (clean-event-queue queue)
@@ -591,13 +590,15 @@
     (set! last-focus-time (vector-ref event 2))
     (make-input-event select-screen screen)))
 \f
+(define reading-event?)
 (define signal-interrupts?)
 (define last-focus-time)
 (define previewer-registration)
 
 (define (with-editor-interrupts-from-x receiver)
-  (fluid-let ((signal-interrupts? true)
-             (last-focus-time false)
+  (fluid-let ((reading-event? #f)
+             (signal-interrupts? #t)
+             (last-focus-time #f)
              (previewer-registration))
     (dynamic-wind
      preview-event-stream