Konsole incorrectly ignores SU (CSI S) if the parameter is bigger than

the scroll region, so clamp it. Reported by Moritz Bunkus.

diff --git a/usr.bin/tmux/tty.c b/usr.bin/tmux/tty.c
index 5551b0f..a298b07 100644 (file)
--- a/usr.bin/tmux/tty.c
+++ b/usr.bin/tmux/tty.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: tty.c,v 1.268 2017/04/25 18:30:29 nicm Exp $ */
+/* $OpenBSD: tty.c,v 1.269 2017/04/28 17:58:44 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1117,7 +1117,7 @@ void
 tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
 {
        struct window_pane      *wp = ctx->wp;
-       u_int                    i;
+       u_int                    i, lines;
 
        if ((!tty_pane_full_width(tty, ctx) && !tty_use_margin(tty)) ||
            tty_fake_bce(tty, wp, 8) ||
@@ -1131,12 +1131,21 @@ tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
        tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
        tty_margin_pane(tty, ctx);
 
-       if (ctx->num == 1 || !tty_term_has(tty->term, TTYC_INDN)) {
+       /*
+        * Konsole has a bug where it will ignore SU if the parameter is more
+        * than the height of the scroll region. Clamping the parameter doesn't
+        * hurt in any case.
+        */
+       lines = tty->rlower - tty->rupper;
+       if (lines > ctx->num)
+               lines = ctx->num;
+
+       if (lines == 1 || !tty_term_has(tty->term, TTYC_INDN)) {
                tty_cursor(tty, tty->rright, tty->rlower);
-               for (i = 0; i < ctx->num; i++)
+               for (i = 0; i < lines; i++)
                        tty_putc(tty, '\n');
        } else
-               tty_putcode1(tty, TTYC_INDN, ctx->num);
+               tty_putcode1(tty, TTYC_INDN, lines);
 }
 
 void