1 /* $OpenBSD: lib_erase.c,v 1.4 2023/10/17 09:52:08 nicm Exp $ */
2
3 /****************************************************************************
4 * Copyright 2020,2022 Thomas E. Dickey *
5 * Copyright 1998-2009,2016 Free Software Foundation, Inc. *
6 * *
7 * Permission is hereby granted, free of charge, to any person obtaining a *
8 * copy of this software and associated documentation files (the *
9 * "Software"), to deal in the Software without restriction, including *
10 * without limitation the rights to use, copy, modify, merge, publish, *
11 * distribute, distribute with modifications, sublicense, and/or sell *
12 * copies of the Software, and to permit persons to whom the Software is *
13 * furnished to do so, subject to the following conditions: *
14 * *
15 * The above copyright notice and this permission notice shall be included *
16 * in all copies or substantial portions of the Software. *
17 * *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
21 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
24 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
25 * *
26 * Except as contained in this notice, the name(s) of the above copyright *
27 * holders shall not be used in advertising or otherwise to promote the *
28 * sale, use or other dealings in this Software without prior written *
29 * authorization. *
30 ****************************************************************************/
31
32 /****************************************************************************
33 * Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
34 * and: Eric S. Raymond <esr@snark.thyrsus.com> *
35 * and: Thomas E. Dickey 1996-on *
36 ****************************************************************************/
37
38 /*
39 ** lib_erase.c
40 **
41 ** The routine werase().
42 **
43 */
44
45 #include <curses.priv.h>
46
47 MODULE_ID("$Id: lib_erase.c,v 1.4 2023/10/17 09:52:08 nicm Exp $")
48
NCURSES_EXPORT(int)49 NCURSES_EXPORT(int)
50 werase(WINDOW *win)
51 {
52 int code = ERR;
53 NCURSES_CH_T *start;
54
55 T((T_CALLED("werase(%p)"), (void *) win));
56
57 if (win) {
58 NCURSES_CH_T blank;
59 NCURSES_CH_T *sp;
60 int y;
61
62 blank = win->_nc_bkgd;
63 for (y = 0; y <= win->_maxy; y++) {
64 NCURSES_CH_T *end;
65
66 start = win->_line[y].text;
67 end = &start[win->_maxx];
68
69 /*
70 * If this is a derived window, we have to handle the case where
71 * a multicolumn character extends into the window that we are
72 * erasing.
73 */
74 if_WIDEC({
75 if (isWidecExt(start[0])) {
76 int x = (win->_parent != 0) ? (win->_begx) : 0;
77 while (x-- > 0) {
78 if (isWidecBase(start[-1])) {
79 --start;
80 break;
81 }
82 --start;
83 }
84 }
85 });
86
87 for (sp = start; sp <= end; sp++)
88 *sp = blank;
89
90 win->_line[y].firstchar = 0;
91 win->_line[y].lastchar = win->_maxx;
92 }
93 win->_curx = win->_cury = 0;
94 win->_flags &= ~_WRAPPED;
95 _nc_synchook(win);
96 code = OK;
97 }
98 returnCode(code);
99 }
100