[src/trunk]: src/lib/libcurses Fix PR lib/55931

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

details:   https://anonhg.NetBSD.org/src/rev/c6b97db9827f
branches:  trunk
changeset: 984214:c6b97db9827f
user:      blymn <blymn%NetBSD.org@localhost>
date:      Sun Jun 27 23:57:08 2021 +0000

description:
Fix PR lib/55931
Only reset outcol if we actually emit a \n as cursor_down may not may
not put the cursor at the start of the next line.

diffstat:

 lib/libcurses/cr_put.c |  18 +++++++++++++++---
 1 files changed, 15 insertions(+), 3 deletions(-)

diffs (60 lines):

diff -r d5045babd074 -r c6b97db9827f lib/libcurses/cr_put.c
--- a/lib/libcurses/cr_put.c    Sun Jun 27 22:41:55 2021 +0000
+++ b/lib/libcurses/cr_put.c    Sun Jun 27 23:57:08 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cr_put.c,v 1.34 2019/05/20 22:17:41 blymn Exp $        */
+/*     $NetBSD: cr_put.c,v 1.35 2021/06/27 23:57:08 blymn Exp $        */
 
 /*
  * Copyright (c) 1981, 1993, 1994
@@ -34,7 +34,7 @@
 #if 0
 static char sccsid[] = "@(#)cr_put.c   8.3 (Berkeley) 5/4/94";
 #else
-__RCSID("$NetBSD: cr_put.c,v 1.34 2019/05/20 22:17:41 blymn Exp $");
+__RCSID("$NetBSD: cr_put.c,v 1.35 2021/06/27 23:57:08 blymn Exp $");
 #endif
 #endif                         /* not lint */
 
@@ -93,6 +93,8 @@
 
 #ifdef DEBUG
        __CTRACE(__CTRACE_OUTPUT, "fgoto: in_refresh=%d\n", in_refresh);
+       __CTRACE(__CTRACE_OUTPUT, "fgoto: outcol=%d, outline=%d, destcol=%d, destline=%d\n",
+               outcol, outline, destcol, destline);
 #endif /* DEBUG */
        if (destcol >= COLS) {
                destline += destcol / COLS;
@@ -214,6 +216,8 @@
 #ifdef DEBUG
        __CTRACE(__CTRACE_OUTPUT, "plod: cnt=%d, in_refresh=%d\n",
            cnt, in_refresh);
+       __CTRACE(__CTRACE_OUTPUT, "plod: plodding from col %d, row %d to col %d, row %d\n",
+           outcol, outline, destcol, destline);
 #endif /* DEBUG */
        plodcnt = plodflg = cnt;
        soutcol = outcol;
@@ -331,6 +335,7 @@
                                plodput('\n');
                        outline++;
                }
+
                outcol = 0;
        }
 dontcr:while (outline < destline) {
@@ -341,7 +346,14 @@
                        plodput('\n');
                if (plodcnt < 0)
                        goto out;
-               if (__NONL || __pfast == 0)
+               /*
+                * If the terminal does a CR with NL or we are in
+                * a mode where a \n will result in an implicit \r
+                * then adjust the outcol to match iff we actually
+                * emitted said \n.
+                */
+               if ((__NONL || __pfast == 0) &&
+                   (!cursor_down || (*cursor_down == '\n')))
                        outcol = 0;
        }
 #ifdef notdef