xref: /openbsd/lib/libcurses/base/lib_bkgd.c (revision c7ef0cfc)
1 /* $OpenBSD: lib_bkgd.c,v 1.4 2023/10/17 09:52:08 nicm Exp $ */
2 
3 /****************************************************************************
4  * Copyright 2018-2020,2021 Thomas E. Dickey                                *
5  * Copyright 1998-2014,2016 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: Juergen Pfeifer                         1997                    *
36  *     and: Sven Verdoolaege                        2000                    *
37  *     and: Thomas E. Dickey                        1996-on                 *
38  ****************************************************************************/
39 
40 #include <curses.priv.h>
41 
42 MODULE_ID("$Id: lib_bkgd.c,v 1.4 2023/10/17 09:52:08 nicm Exp $")
43 
44 static const NCURSES_CH_T blank = NewChar(BLANK_TEXT);
45 
46 /*
47  * Set the window's background information.
48  */
49 #if USE_WIDEC_SUPPORT
50 NCURSES_EXPORT(void)
51 #else
52 static NCURSES_INLINE void
53 #endif
wbkgrndset(WINDOW * win,const ARG_CH_T ch)54 wbkgrndset(WINDOW *win, const ARG_CH_T ch)
55 {
56     T((T_CALLED("wbkgrndset(%p,%s)"), (void *) win, _tracech_t(ch)));
57 
58     if (win) {
59 	attr_t off = AttrOf(win->_nc_bkgd);
60 	attr_t on = AttrOf(CHDEREF(ch));
61 
62 	toggle_attr_off(WINDOW_ATTRS(win), off);
63 	toggle_attr_on(WINDOW_ATTRS(win), on);
64 
65 #if NCURSES_EXT_COLORS
66 	{
67 	    int pair;
68 
69 	    if (GetPair(win->_nc_bkgd) != 0)
70 		SET_WINDOW_PAIR(win, 0);
71 	    if ((pair = GetPair(CHDEREF(ch))) != 0)
72 		SET_WINDOW_PAIR(win, pair);
73 	}
74 #endif
75 
76 	if (CharOf(CHDEREF(ch)) == L('\0')) {
77 	    SetChar(win->_nc_bkgd, BLANK_TEXT, AttrOf(CHDEREF(ch)));
78 	    if_EXT_COLORS(SetPair(win->_nc_bkgd, GetPair(CHDEREF(ch))));
79 	} else {
80 	    win->_nc_bkgd = CHDEREF(ch);
81 	}
82 #if USE_WIDEC_SUPPORT
83 	/*
84 	 * If we're compiled for wide-character support, _bkgrnd is the
85 	 * preferred location for the background information since it stores
86 	 * more than _bkgd.  Update _bkgd each time we modify _bkgrnd, so the
87 	 * macro getbkgd() will work.
88 	 */
89 	{
90 	    cchar_t wch;
91 	    int tmp;
92 
93 	    memset(&wch, 0, sizeof(wch));
94 	    (void) wgetbkgrnd(win, &wch);
95 	    tmp = _nc_to_char((wint_t) CharOf(wch));
96 
97 	    win->_bkgd = (((tmp == EOF) ? ' ' : (chtype) tmp)
98 			  | (AttrOf(wch) & ALL_BUT_COLOR)
99 			  | (chtype) ColorPair(GET_WINDOW_PAIR(win)));
100 	}
101 #endif
102     }
103     returnVoid;
104 }
105 
106 NCURSES_EXPORT(void)
wbkgdset(WINDOW * win,chtype ch)107 wbkgdset(WINDOW *win, chtype ch)
108 {
109     NCURSES_CH_T wch;
110     T((T_CALLED("wbkgdset(%p,%s)"), (void *) win, _tracechtype(ch)));
111     SetChar2(wch, ch);
112     wbkgrndset(win, CHREF(wch));
113     returnVoid;
114 }
115 
116 /*
117  * Set the window's background information and apply it to each cell.
118  */
119 static NCURSES_INLINE int
_nc_background(WINDOW * win,const ARG_CH_T ch,bool narrow)120 _nc_background(WINDOW *win, const ARG_CH_T ch, bool narrow)
121 {
122 #undef  SP_PARM
123 #define SP_PARM SP		/* to use Charable() */
124     int code = ERR;
125 
126 #if USE_WIDEC_SUPPORT
127     T((T_CALLED("%s(%p,%s)"),
128        narrow ? "wbkgd" : "wbkgrnd",
129        (void *) win,
130        _tracecchar_t(ch)));
131 #define TraceChar(c) _tracecchar_t2(1, &(c))
132 #else
133     T((T_CALLED("%s(%p,%s)"),
134        "wbkgd",
135        (void *) win,
136        _tracech_t(ch)));
137     (void) narrow;
138 #define TraceChar(c) _tracechar(CharOf(c))
139 #endif
140 
141     if (SP == 0) {
142 	;
143     } else if (win) {
144 	NCURSES_CH_T new_bkgd = CHDEREF(ch);
145 	NCURSES_CH_T old_bkgd;
146 	int y;
147 	NCURSES_CH_T old_char;
148 	attr_t old_attr;
149 	int old_pair;
150 	NCURSES_CH_T new_char;
151 	attr_t new_attr;
152 	int new_pair;
153 
154 	/* SVr4 trims color info if non-color terminal */
155 	if (!SP->_pair_limit) {
156 	    RemAttr(new_bkgd, A_COLOR);
157 	    SetPair(new_bkgd, 0);
158 	}
159 
160 	/* avoid setting background-character to a null */
161 	if (CharOf(new_bkgd) == 0) {
162 	    NCURSES_CH_T tmp_bkgd = blank;
163 	    SetAttr(tmp_bkgd, AttrOf(new_bkgd));
164 	    SetPair(tmp_bkgd, GetPair(new_bkgd));
165 	    new_bkgd = tmp_bkgd;
166 	}
167 
168 	memset(&old_bkgd, 0, sizeof(old_bkgd));
169 	(void) wgetbkgrnd(win, &old_bkgd);
170 
171 	if (!memcmp(&old_bkgd, &new_bkgd, sizeof(new_bkgd))) {
172 	    T(("...unchanged"));
173 	    returnCode(OK);
174 	}
175 
176 	old_char = old_bkgd;
177 	RemAttr(old_char, ~A_CHARTEXT);
178 	old_attr = AttrOf(old_bkgd);
179 	old_pair = GetPair(old_bkgd);
180 
181 	if (!(old_attr & A_COLOR)) {
182 	    old_pair = 0;
183 	}
184 	T(("... old background char %s, attr %s, pair %d",
185 	   TraceChar(old_char), _traceattr(old_attr), old_pair));
186 
187 	new_char = new_bkgd;
188 	RemAttr(new_char, ~A_CHARTEXT);
189 	new_attr = AttrOf(new_bkgd);
190 	new_pair = GetPair(new_bkgd);
191 
192 	/* SVr4 limits background character to printable 7-bits */
193 	if (
194 #if USE_WIDEC_SUPPORT
195 	       narrow &&
196 #endif
197 	       !Charable(new_bkgd)) {
198 	    new_char = old_char;
199 	}
200 	if (!(new_attr & A_COLOR)) {
201 	    new_pair = 0;
202 	}
203 	T(("... new background char %s, attr %s, pair %d",
204 	   TraceChar(new_char), _traceattr(new_attr), new_pair));
205 
206 	(void) wbkgrndset(win, CHREF(new_bkgd));
207 
208 	/* SVr4 updates color pair if old/new match, otherwise just attrs */
209 	if ((new_pair != 0) && (new_pair == old_pair)) {
210 	    WINDOW_ATTRS(win) = new_attr;
211 	    SET_WINDOW_PAIR(win, new_pair);
212 	} else {
213 	    WINDOW_ATTRS(win) = new_attr;
214 	}
215 
216 	for (y = 0; y <= win->_maxy; y++) {
217 	    int x;
218 
219 	    for (x = 0; x <= win->_maxx; x++) {
220 		NCURSES_CH_T *cp = &(win->_line[y].text[x]);
221 		int tmp_pair = GetPair(*cp);
222 		attr_t tmp_attr = AttrOf(*cp);
223 
224 		if (CharEq(*cp, old_bkgd)) {
225 #if USE_WIDEC_SUPPORT
226 		    if (!narrow) {
227 			if (Charable(new_bkgd)) {
228 			    SetChar2(*cp, CharOf(new_char));
229 			} else {
230 			    SetChar(*cp, L' ', AttrOf(new_char));
231 			}
232 			memcpy(cp->chars,
233 			       new_char.chars,
234 			       CCHARW_MAX * sizeof(cp->chars[0]));
235 		    } else
236 #endif
237 			SetChar2(*cp, CharOf(new_char));
238 		}
239 		if (tmp_pair != 0) {
240 		    if (tmp_pair == old_pair) {
241 			SetAttr(*cp, (tmp_attr & ~old_attr) | new_attr);
242 			SetPair(*cp, new_pair);
243 		    } else {
244 			SetAttr(*cp,
245 				(tmp_attr & (~old_attr | A_COLOR))
246 				| (new_attr & ALL_BUT_COLOR));
247 		    }
248 		} else {
249 		    SetAttr(*cp, (tmp_attr & ~old_attr) | new_attr);
250 		    SetPair(*cp, new_pair);
251 		}
252 	    }
253 	}
254 	touchwin(win);
255 	_nc_synchook(win);
256 	code = OK;
257     }
258     returnCode(code);
259 }
260 
261 #if USE_WIDEC_SUPPORT
262 NCURSES_EXPORT(int)
wbkgrnd(WINDOW * win,const ARG_CH_T ch)263 wbkgrnd(WINDOW *win, const ARG_CH_T ch)
264 {
265     return _nc_background(win, ch, FALSE);
266 }
267 #endif
268 
269 NCURSES_EXPORT(int)
wbkgd(WINDOW * win,chtype ch)270 wbkgd(WINDOW *win, chtype ch)
271 {
272     NCURSES_CH_T wch;
273     SetChar2(wch, ch);
274     return _nc_background(win, CHREF(wch), TRUE);
275 }
276