[src/trunk]: src/lib/libcurses When doupdate is called, check for typeahead i...

[roy <roy%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2a4a8060fce7
branches:  trunk
changeset: 350324:2a4a8060fce7
user:      roy <roy%NetBSD.org@localhost>
date:      Tue Jan 10 10:33:49 2017 +0000

description:
When doupdate is called, check for typeahead input after N lines changed
instead of aborting really early.

This allows some screen update when holding the page down key for example.

diffstat:

 lib/libcurses/refresh.c |  34 +++++++++++++++++++++-------------
 1 files changed, 21 insertions(+), 13 deletions(-)

diffs (83 lines):

diff -r 3a60124b515d -r 2a4a8060fce7 lib/libcurses/refresh.c
--- a/lib/libcurses/refresh.c   Tue Jan 10 10:13:24 2017 +0000
+++ b/lib/libcurses/refresh.c   Tue Jan 10 10:33:49 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: refresh.c,v 1.84 2017/01/10 09:32:01 roy Exp $ */
+/*     $NetBSD: refresh.c,v 1.85 2017/01/10 10:33:49 roy Exp $ */
 
 /*
  * Copyright (c) 1981, 1993, 1994
@@ -34,7 +34,7 @@
 #if 0
 static char sccsid[] = "@(#)refresh.c  8.7 (Berkeley) 8/13/94";
 #else
-__RCSID("$NetBSD: refresh.c,v 1.84 2017/01/10 09:32:01 roy Exp $");
+__RCSID("$NetBSD: refresh.c,v 1.85 2017/01/10 10:33:49 roy Exp $");
 #endif
 #endif                         /* not lint */
 
@@ -58,6 +58,8 @@
 int linecmp( __LDATA *, __LDATA *, size_t );
 #endif /* HAVE_WCHAR */
 
+#define        CHECK_INTERVAL          5 /* Change N lines before checking typeahead */
+
 #ifndef _CURSES_USE_MACROS
 
 /*
@@ -498,7 +500,7 @@
        WINDOW  *win;
        __LINE  *wlp, *vlp;
        short    wy;
-       int      dnum, was_cleared;
+       int      dnum, was_cleared, changed;
 #ifdef HAVE_WCHAR
        __LDATA *lp;
        nschar_t *np;
@@ -595,16 +597,6 @@
                        quickch();
        }
 
-       if (_cursesi_screen->checkfd != -1) {
-               struct pollfd fds[1];
-
-               /* If we have input, abort the update. */
-               fds[0].fd = _cursesi_screen->checkfd;
-               fds[0].events = POLLIN;
-               if (poll(fds, 1, 0) > 0)
-                       goto cleanup;
-       }
-
 #ifdef DEBUG
        {
                int     i, j;
@@ -657,6 +649,7 @@
        }
 #endif /* DEBUG */
 
+       changed = 0;
        for (wy = 0; wy < win->maxy; wy++) {
                wlp = win->alines[wy];
                vlp = _cursesi_screen->__virtscr->alines[win->begy + wy];
@@ -696,6 +689,21 @@
 #endif /* DEBUG */
                                        wlp->flags &= ~(__ISDIRTY | __ISFORCED);
                                }
+
+                               /* Check if we have input after
+                                * changing N lines. */
+                               if (_cursesi_screen->checkfd != -1 &&
+                                   ++changed == CHECK_INTERVAL)
+                               {
+                                       struct pollfd fds[1];
+
+                                       /* If we have input, abort. */
+                                       fds[0].fd = _cursesi_screen->checkfd;
+                                       fds[0].events = POLLIN;
+                                       if (poll(fds, 1, 0) > 0)
+                                               goto cleanup;
+                                       changed = 0;
+                               }
                        }
                }