Sync OpenBSD patchset 426:

Some terminals don't correctly clear their let's-wrap flag after changing the
scroll region (which moves the cursor to 0,0). This means that if the cursor
was at the edge of the screen, any further output after scroll region change
incorrectly causes a line wrap. Add a workaround to move the cursor to position
0 if it is at the screen edge before changing scroll region.

1 files changed, 10 insertions, 1 deletions

diff --git a/tty.c b/tty.c
index a6dac18d..c31706f7 100644
--- a/tty.c
+++ b/tty.c
@@ -1,4 +1,4 @@
-/* $Id: tty.c,v 1.158 2009-10-23 17:16:24 tcunha Exp $ */
+/* $Id: tty.c,v 1.159 2009-10-23 17:22:39 tcunha Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -960,6 +960,15 @@ tty_region(struct tty *tty, u_int rupper, u_int rlower)
 	tty->rupper = rupper;
 	tty->rlower = rlower;
 
+	/*
+	 * Some terminals (such as PuTTY) do not correctly reset the cursor to
+	 * 0,0 if it is beyond the last column (they do not reset their wrap
+	 * flag so further output causes a line feed). As a workaround, do an
+	 * explicit move to 0 first.
+	 */
+	if (tty->cx >= tty->sx)
+		tty_cursor(tty, 0, tty->cy);
+
 	tty->cx = 0;
 	tty->cy = 0;