1 /****************************************************************************
2 * Copyright 2020,2022 Thomas E. Dickey *
3 * Copyright 1998-2009,2016 Free Software Foundation, Inc. *
4 * *
5 * Permission is hereby granted, free of charge, to any person obtaining a *
6 * copy of this software and associated documentation files (the *
7 * "Software"), to deal in the Software without restriction, including *
8 * without limitation the rights to use, copy, modify, merge, publish, *
9 * distribute, distribute with modifications, sublicense, and/or sell *
10 * copies of the Software, and to permit persons to whom the Software is *
11 * furnished to do so, subject to the following conditions: *
12 * *
13 * The above copyright notice and this permission notice shall be included *
14 * in all copies or substantial portions of the Software. *
15 * *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
19 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
21 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
22 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
23 * *
24 * Except as contained in this notice, the name(s) of the above copyright *
25 * holders shall not be used in advertising or otherwise to promote the *
26 * sale, use or other dealings in this Software without prior written *
27 * authorization. *
28 ****************************************************************************/
29
30 /****************************************************************************
31 * Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
32 * and: Eric S. Raymond <esr@snark.thyrsus.com> *
33 * and: Thomas E. Dickey 1996-on *
34 ****************************************************************************/
35
36 /*
37 ** lib_erase.c
38 **
39 ** The routine werase().
40 **
41 */
42
43 #include <curses.priv.h>
44
45 MODULE_ID("$Id: lib_erase.c,v 1.20 2022/09/03 21:40:27 tom Exp $")
46
NCURSES_EXPORT(int)47 NCURSES_EXPORT(int)
48 werase(WINDOW *win)
49 {
50 int code = ERR;
51 NCURSES_CH_T *start;
52
53 T((T_CALLED("werase(%p)"), (void *) win));
54
55 if (win) {
56 NCURSES_CH_T blank;
57 NCURSES_CH_T *sp;
58 int y;
59
60 blank = win->_nc_bkgd;
61 for (y = 0; y <= win->_maxy; y++) {
62 NCURSES_CH_T *end;
63
64 start = win->_line[y].text;
65 end = &start[win->_maxx];
66
67 /*
68 * If this is a derived window, we have to handle the case where
69 * a multicolumn character extends into the window that we are
70 * erasing.
71 */
72 if_WIDEC({
73 if (isWidecExt(start[0])) {
74 int x = (win->_parent != 0) ? (win->_begx) : 0;
75 while (x-- > 0) {
76 if (isWidecBase(start[-1])) {
77 --start;
78 break;
79 }
80 --start;
81 }
82 }
83 });
84
85 for (sp = start; sp <= end; sp++)
86 *sp = blank;
87
88 win->_line[y].firstchar = 0;
89 win->_line[y].lastchar = win->_maxx;
90 }
91 win->_curx = win->_cury = 0;
92 win->_flags &= ~_WRAPPED;
93 _nc_synchook(win);
94 code = OK;
95 }
96 returnCode(code);
97 }
98