ncurses 6.2 - patch 20210418
[ncurses.git] / ncurses / base / lib_bkgd.c
1 /****************************************************************************
2  * Copyright 2018-2020,2021 Thomas E. Dickey                                *
3  * Copyright 1998-2014,2016 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: Juergen Pfeifer                         1997                    *
34  *     and: Sven Verdoolaege                        2000                    *
35  *     and: Thomas E. Dickey                        1996-on                 *
36  ****************************************************************************/
37
38 #include <curses.priv.h>
39
40 MODULE_ID("$Id: lib_bkgd.c,v 1.62 2021/02/13 20:06:54 tom Exp $")
41
42 static const NCURSES_CH_T blank = NewChar(BLANK_TEXT);
43
44 /*
45  * Set the window's background information.
46  */
47 #if USE_WIDEC_SUPPORT
48 NCURSES_EXPORT(void)
49 #else
50 static NCURSES_INLINE void
51 #endif
52 wbkgrndset(WINDOW *win, const ARG_CH_T ch)
53 {
54     T((T_CALLED("wbkgrndset(%p,%s)"), (void *) win, _tracech_t(ch)));
55
56     if (win) {
57         attr_t off = AttrOf(win->_nc_bkgd);
58         attr_t on = AttrOf(CHDEREF(ch));
59
60         toggle_attr_off(WINDOW_ATTRS(win), off);
61         toggle_attr_on(WINDOW_ATTRS(win), on);
62
63 #if NCURSES_EXT_COLORS
64         {
65             int pair;
66
67             if ((pair = GetPair(win->_nc_bkgd)) != 0)
68                 SET_WINDOW_PAIR(win, 0);
69             if ((pair = GetPair(CHDEREF(ch))) != 0)
70                 SET_WINDOW_PAIR(win, pair);
71         }
72 #endif
73
74         if (CharOf(CHDEREF(ch)) == L('\0')) {
75             SetChar(win->_nc_bkgd, BLANK_TEXT, AttrOf(CHDEREF(ch)));
76             if_EXT_COLORS(SetPair(win->_nc_bkgd, GetPair(CHDEREF(ch))));
77         } else {
78             win->_nc_bkgd = CHDEREF(ch);
79         }
80 #if USE_WIDEC_SUPPORT
81         /*
82          * If we're compiled for wide-character support, _bkgrnd is the
83          * preferred location for the background information since it stores
84          * more than _bkgd.  Update _bkgd each time we modify _bkgrnd, so the
85          * macro getbkgd() will work.
86          */
87         {
88             cchar_t wch;
89             int tmp;
90
91             memset(&wch, 0, sizeof(wch));
92             (void) wgetbkgrnd(win, &wch);
93             tmp = _nc_to_char((wint_t) CharOf(wch));
94
95             win->_bkgd = (((tmp == EOF) ? ' ' : (chtype) tmp)
96                           | (AttrOf(wch) & ALL_BUT_COLOR)
97                           | (chtype) ColorPair(GET_WINDOW_PAIR(win)));
98         }
99 #endif
100     }
101     returnVoid;
102 }
103
104 NCURSES_EXPORT(void)
105 wbkgdset(WINDOW *win, chtype ch)
106 {
107     NCURSES_CH_T wch;
108     T((T_CALLED("wbkgdset(%p,%s)"), (void *) win, _tracechtype(ch)));
109     SetChar2(wch, ch);
110     wbkgrndset(win, CHREF(wch));
111     returnVoid;
112 }
113
114 /*
115  * Set the window's background information and apply it to each cell.
116  */
117 static NCURSES_INLINE int
118 _nc_background(WINDOW *win, const ARG_CH_T ch, bool narrow)
119 {
120 #undef  SP_PARM
121 #define SP_PARM SP              /* to use Charable() */
122     int code = ERR;
123
124 #if USE_WIDEC_SUPPORT
125     T((T_CALLED("%s(%p,%s)"),
126        narrow ? "wbkgd" : "wbkgrnd",
127        (void *) win,
128        _tracecchar_t(ch)));
129 #define TraceChar(c) _tracecchar_t2(1, &(c))
130 #else
131     T((T_CALLED("%s(%p,%s)"),
132        "wbkgd",
133        (void *) win,
134        _tracech_t(ch)));
135     (void) narrow;
136 #define TraceChar(c) _tracechar(CharOf(c))
137 #endif
138
139     if (SP == 0) {
140         ;
141     } else if (win) {
142         NCURSES_CH_T new_bkgd = CHDEREF(ch);
143         NCURSES_CH_T old_bkgd;
144         int y;
145         NCURSES_CH_T old_char;
146         attr_t old_attr;
147         int old_pair;
148         NCURSES_CH_T new_char;
149         attr_t new_attr;
150         int new_pair;
151
152         /* SVr4 trims color info if non-color terminal */
153         if (!SP->_pair_limit) {
154             RemAttr(new_bkgd, A_COLOR);
155             SetPair(new_bkgd, 0);
156         }
157
158         /* avoid setting background-character to a null */
159         if (CharOf(new_bkgd) == 0) {
160             NCURSES_CH_T tmp_bkgd = blank;
161             SetAttr(tmp_bkgd, AttrOf(new_bkgd));
162             SetPair(tmp_bkgd, GetPair(new_bkgd));
163             new_bkgd = tmp_bkgd;
164         }
165
166         memset(&old_bkgd, 0, sizeof(old_bkgd));
167         (void) wgetbkgrnd(win, &old_bkgd);
168
169         if (!memcmp(&old_bkgd, &new_bkgd, sizeof(new_bkgd))) {
170             T(("...unchanged"));
171             returnCode(OK);
172         }
173
174         old_char = old_bkgd;
175         RemAttr(old_char, ~A_CHARTEXT);
176         old_attr = AttrOf(old_bkgd);
177         old_pair = GetPair(old_bkgd);
178
179         if (!(old_attr & A_COLOR)) {
180             old_pair = 0;
181         }
182         T(("... old background char %s, attr %s, pair %d",
183            TraceChar(old_char), _traceattr(old_attr), old_pair));
184
185         new_char = new_bkgd;
186         RemAttr(new_char, ~A_CHARTEXT);
187         new_attr = AttrOf(new_bkgd);
188         new_pair = GetPair(new_bkgd);
189
190         /* SVr4 limits background character to printable 7-bits */
191         if (
192 #if USE_WIDEC_SUPPORT
193                narrow &&
194 #endif
195                !Charable(new_bkgd)) {
196             new_char = old_char;
197         }
198         if (!(new_attr & A_COLOR)) {
199             new_pair = 0;
200         }
201         T(("... new background char %s, attr %s, pair %d",
202            TraceChar(new_char), _traceattr(new_attr), new_pair));
203
204         (void) wbkgrndset(win, CHREF(new_bkgd));
205
206         /* SVr4 updates color pair if old/new match, otherwise just attrs */
207         if ((new_pair != 0) && (new_pair == old_pair)) {
208             WINDOW_ATTRS(win) = new_attr;
209             SET_WINDOW_PAIR(win, new_pair);
210         } else {
211             WINDOW_ATTRS(win) = new_attr;
212         }
213
214         for (y = 0; y <= win->_maxy; y++) {
215             int x;
216
217             for (x = 0; x <= win->_maxx; x++) {
218                 NCURSES_CH_T *cp = &(win->_line[y].text[x]);
219                 int tmp_pair = GetPair(*cp);
220                 attr_t tmp_attr = AttrOf(*cp);
221
222                 if (CharEq(*cp, old_bkgd)) {
223 #if USE_WIDEC_SUPPORT
224                     if (!narrow) {
225                         if (Charable(new_bkgd)) {
226                             SetChar2(*cp, CharOf(new_char));
227                         } else {
228                             SetChar(*cp, L' ', AttrOf(new_char));
229                         }
230                         memcpy(cp->chars,
231                                new_char.chars,
232                                CCHARW_MAX * sizeof(cp->chars[0]));
233                     } else
234 #endif
235                         SetChar2(*cp, CharOf(new_char));
236                 }
237                 if (tmp_pair != 0) {
238                     if (tmp_pair == old_pair) {
239                         SetAttr(*cp, (tmp_attr & ~old_attr) | new_attr);
240                         SetPair(*cp, new_pair);
241                     } else {
242                         SetAttr(*cp,
243                                 (tmp_attr & (~old_attr | A_COLOR))
244                                 | (new_attr & ALL_BUT_COLOR));
245                     }
246                 } else {
247                     SetAttr(*cp, (tmp_attr & ~old_attr) | new_attr);
248                     SetPair(*cp, new_pair);
249                 }
250             }
251         }
252         touchwin(win);
253         _nc_synchook(win);
254         code = OK;
255     }
256     returnCode(code);
257 }
258
259 #if USE_WIDEC_SUPPORT
260 NCURSES_EXPORT(int)
261 wbkgrnd(WINDOW *win, const ARG_CH_T ch)
262 {
263     return _nc_background(win, ch, FALSE);
264 }
265 #endif
266
267 NCURSES_EXPORT(int)
268 wbkgd(WINDOW *win, chtype ch)
269 {
270     NCURSES_CH_T wch;
271     SetChar2(wch, ch);
272     return _nc_background(win, CHREF(wch), TRUE);
273 }