1 files changed, 35 insertions, 12 deletions

diff --git a/src/keyboard.c b/src/keyboard.c
index d2ab3a80249..441c23e10c7 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -1897,6 +1897,9 @@ int poll_suppress_count;
 
 static struct atimer *poll_timer;
 
+/* The poll period that constructed this timer.  */
+static Lisp_Object poll_timer_time;
+
 #if defined CYGWIN || defined DOS_NT
 /* Poll for input, so that we catch a C-g if it comes in.  */
 void
@@ -1938,17 +1941,18 @@ start_polling (void)
 
       /* If poll timer doesn't exist, or we need one with
          a different interval, start a new one.  */
-      if (poll_timer == NULL
-          || poll_timer->interval.tv_sec != polling_period)
+      if (NUMBERP (Vpolling_period)
+          && (poll_timer == NULL
+              || NILP (Fequal (Vpolling_period, poll_timer_time))))
         {
-          time_t period = max (1, min (polling_period, TYPE_MAXIMUM (time_t)));
-          struct timespec interval = make_timespec (period, 0);
+          struct timespec interval = dtotimespec (XFLOATINT (Vpolling_period));
 
           if (poll_timer)
             cancel_atimer (poll_timer);
 
           poll_timer = start_atimer (ATIMER_CONTINUOUS, interval,
                                      poll_for_input, NULL);
+          poll_timer_time = Vpolling_period;
         }
 
       /* Let the timer's callback function poll for input
@@ -2016,14 +2020,28 @@ void
 bind_polling_period (int n)
 {
 #ifdef POLL_FOR_INPUT
-  intmax_t new = polling_period;
+  if (FIXNUMP (Vpolling_period))
+    {
+      intmax_t new = XFIXNUM (Vpolling_period);
+
+      if (n > new)
+        new = n;
+
+      stop_other_atimers (poll_timer);
+      stop_polling ();
+      specbind (Qpolling_period, make_int (new));
+    }
+  else if (FLOATP (Vpolling_period))
+    {
+      double new = XFLOAT_DATA (Vpolling_period);
 
-  if (n > new)
-    new = n;
+      stop_other_atimers (poll_timer);
+      stop_polling ();
+      specbind (Qpolling_period, (n > new
+                                  ? make_int (n)
+                                  : Vpolling_period));
+    }
 
-  stop_other_atimers (poll_timer);
-  stop_polling ();
-  specbind (Qpolling_period, make_int (new));
   /* Start a new alarm with the new period.  */
   start_polling ();
 #endif
@@ -12066,6 +12084,11 @@ syms_of_keyboard (void)
   help_form_saved_window_configs = Qnil;
   staticpro (&help_form_saved_window_configs);
 
+#ifdef POLL_FOR_INPUT
+  poll_timer_time = Qnil;
+  staticpro (&poll_timer_time);
+#endif
+
   defsubr (&Scurrent_idle_time);
   defsubr (&Sevent_symbol_parse_modifiers);
   defsubr (&Sevent_convert_list);
@@ -12223,12 +12246,12 @@ The value may be integer or floating point.
 If the value is zero, don't echo at all.  */);
   Vecho_keystrokes = make_fixnum (1);
 
-  DEFVAR_INT ("polling-period", polling_period,
+  DEFVAR_LISP ("polling-period", Vpolling_period,
               doc: /* Interval between polling for input during Lisp execution.
 The reason for polling is to make C-g work to stop a running program.
 Polling is needed only when using X windows and SIGIO does not work.
 Polling is automatically disabled in all other cases.  */);
-  polling_period = 2;
+  Vpolling_period = make_float (2.0);
 
   DEFVAR_LISP ("double-click-time", Vdouble_click_time,
                doc: /* Maximum time between mouse clicks to make a double-click.