1 /* $OpenBSD: lib_pad.c,v 1.6 2023/10/17 09:52:08 nicm Exp $ */
2
3 /****************************************************************************
4 * Copyright 2020,2021 Thomas E. Dickey *
5 * Copyright 1998-2010,2017 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 * and: Juergen Pfeifer 2009 *
37 ****************************************************************************/
38
39 /*
40 * lib_pad.c
41 * newpad -- create a new pad
42 * pnoutrefresh -- refresh a pad, no update
43 * pechochar -- add a char to a pad and refresh
44 */
45
46 #include <curses.priv.h>
47
48 MODULE_ID("$Id: lib_pad.c,v 1.6 2023/10/17 09:52:08 nicm Exp $")
49
NCURSES_EXPORT(WINDOW *)50 NCURSES_EXPORT(WINDOW *)
51 NCURSES_SP_NAME(newpad) (NCURSES_SP_DCLx int l, int c)
52 {
53 WINDOW *win;
54 NCURSES_CH_T *ptr;
55 int i;
56
57 T((T_CALLED("newpad(%p,%d, %d)"), (void *) SP_PARM, l, c));
58
59 if (l <= 0 || c <= 0)
60 returnWin(0);
61
62 win = NCURSES_SP_NAME(_nc_makenew) (NCURSES_SP_ARGx l, c, 0, 0, _ISPAD);
63 if (win == NULL)
64 returnWin(0);
65
66 for (i = 0; i < l; i++) {
67 if_USE_SCROLL_HINTS(win->_line[i].oldindex = _NEWINDEX);
68 if ((win->_line[i].text = typeCalloc(NCURSES_CH_T, ((size_t) c))) == 0) {
69 (void) _nc_freewin(win);
70 returnWin(0);
71 }
72 for (ptr = win->_line[i].text; ptr < win->_line[i].text + c; ptr++)
73 SetChar(*ptr, BLANK_TEXT, BLANK_ATTR);
74 }
75
76 returnWin(win);
77 }
78
79 #if NCURSES_SP_FUNCS
80 NCURSES_EXPORT(WINDOW *)
newpad(int l,int c)81 newpad(int l, int c)
82 {
83 return NCURSES_SP_NAME(newpad) (CURRENT_SCREEN, l, c);
84 }
85 #endif
86
87 NCURSES_EXPORT(WINDOW *)
subpad(WINDOW * orig,int l,int c,int begy,int begx)88 subpad(WINDOW *orig, int l, int c, int begy, int begx)
89 {
90 WINDOW *win = (WINDOW *) 0;
91
92 T((T_CALLED("subpad(%d, %d)"), l, c));
93
94 if (orig) {
95 if (!IS_PAD(orig)
96 || ((win = derwin(orig, l, c, begy, begx)) == NULL))
97 returnWin(0);
98 }
99 returnWin(win);
100 }
101
102 NCURSES_EXPORT(int)
prefresh(WINDOW * win,int pminrow,int pmincol,int sminrow,int smincol,int smaxrow,int smaxcol)103 prefresh(WINDOW *win,
104 int pminrow,
105 int pmincol,
106 int sminrow,
107 int smincol,
108 int smaxrow,
109 int smaxcol)
110 {
111 #if NCURSES_SP_FUNCS
112 SCREEN *sp = _nc_screen_of(win);
113 #endif
114
115 T((T_CALLED("prefresh()")));
116 if (pnoutrefresh(win, pminrow, pmincol, sminrow, smincol, smaxrow,
117 smaxcol) != ERR
118 && NCURSES_SP_NAME(doupdate) (NCURSES_SP_ARG) != ERR) {
119 returnCode(OK);
120 }
121 returnCode(ERR);
122 }
123
124 NCURSES_EXPORT(int)
pnoutrefresh(WINDOW * win,int pminrow,int pmincol,int sminrow,int smincol,int smaxrow,int smaxcol)125 pnoutrefresh(WINDOW *win,
126 int pminrow,
127 int pmincol,
128 int sminrow,
129 int smincol,
130 int smaxrow,
131 int smaxcol)
132 {
133 int i, j;
134 int m, n;
135 int pmaxrow;
136 int pmaxcol;
137 SCREEN *sp;
138
139 #if USE_SCROLL_HINTS
140 const int my_len = 2; /* parameterize the threshold for hardscroll */
141 NCURSES_SIZE_T displaced;
142 bool wide;
143 #endif
144
145 T((T_CALLED("pnoutrefresh(%p, %d, %d, %d, %d, %d, %d)"),
146 (void *) win, pminrow, pmincol, sminrow, smincol, smaxrow, smaxcol));
147
148 if (win == 0)
149 returnCode(ERR);
150
151 if (!IS_PAD(win))
152 returnCode(ERR);
153
154 sp = _nc_screen_of(win);
155
156 /* negative values are interpreted as zero */
157 if (pminrow < 0)
158 pminrow = 0;
159 if (pmincol < 0)
160 pmincol = 0;
161 if (sminrow < 0)
162 sminrow = 0;
163 if (smincol < 0)
164 smincol = 0;
165
166 pmaxrow = pminrow + smaxrow - sminrow;
167 pmaxcol = pmincol + smaxcol - smincol;
168
169 T((" pminrow + smaxrow - sminrow %ld, win->_maxy %ld",
170 (long) pmaxrow, (long) win->_maxy));
171 T((" pmincol + smaxcol - smincol %ld, win->_maxx %ld",
172 (long) pmaxcol, (long) win->_maxx));
173
174 /*
175 * Trim the caller's screen size back to the actual limits.
176 */
177 if (pmaxrow > win->_maxy) {
178 smaxrow -= (pmaxrow - win->_maxy);
179 pmaxrow = pminrow + smaxrow - sminrow;
180 }
181 if (pmaxcol > win->_maxx) {
182 smaxcol -= (pmaxcol - win->_maxx);
183 pmaxcol = pmincol + smaxcol - smincol;
184 }
185
186 if (smaxrow >= screen_lines(sp)
187 || smaxcol >= screen_columns(sp)
188 || sminrow > smaxrow
189 || smincol > smaxcol)
190 returnCode(ERR);
191
192 T(("pad being refreshed"));
193
194 #ifdef TRACE
195 if (USE_TRACEF(TRACE_UPDATE)) {
196 _tracedump("...pad", win);
197 _nc_unlock_global(tracef);
198 }
199 #endif /* TRACE */
200 #if USE_SCROLL_HINTS
201 if (win->_pad._pad_y >= 0) {
202 displaced = pminrow - win->_pad._pad_y
203 - (sminrow - win->_pad._pad_top);
204 T(("pad being shifted by %d line(s)", displaced));
205 } else
206 displaced = 0;
207 #endif
208
209 /*
210 * For pure efficiency, we'd want to transfer scrolling information
211 * from the pad to newscr whenever the window is wide enough that
212 * its update will dominate the cost of the update for the horizontal
213 * band of newscr that it occupies. Unfortunately, this threshold
214 * tends to be complex to estimate, and in any case scrolling the
215 * whole band and rewriting the parts outside win's image would look
216 * really ugly. So. What we do is consider the pad "wide" if it
217 * either (a) occupies the whole width of newscr, or (b) occupies
218 * all but at most one column on either vertical edge of the screen
219 * (this caters to fussy people who put boxes around full-screen
220 * windows). Note that changing this formula will not break any code,
221 * merely change the costs of various update cases.
222 */
223 #if USE_SCROLL_HINTS
224 wide = (smincol < my_len && smaxcol > (NewScreen(sp)->_maxx - my_len));
225 #endif
226
227 for (i = pminrow, m = sminrow + win->_yoffset;
228 i <= pmaxrow && m <= NewScreen(sp)->_maxy;
229 i++, m++) {
230 register struct ldat *nline = &NewScreen(sp)->_line[m];
231 register struct ldat *oline = &win->_line[i];
232 for (j = pmincol, n = smincol; j <= pmaxcol; j++, n++) {
233 NCURSES_CH_T ch = oline->text[j];
234 #if USE_WIDEC_SUPPORT
235 /*
236 * Special case for leftmost character of the displayed area.
237 * Only half of a double-width character may be visible.
238 */
239 if (j == pmincol
240 && j > 0
241 && isWidecExt(ch)) {
242 SetChar(ch, L(' '), AttrOf(oline->text[j - 1]));
243 }
244 #endif
245 if (!CharEq(ch, nline->text[n])) {
246 nline->text[n] = ch;
247 CHANGED_CELL(nline, n);
248 }
249 }
250
251 #if USE_SCROLL_HINTS
252 if (wide) {
253 int nind = m + displaced;
254 if (oline->oldindex < 0
255 || nind < sminrow
256 || nind > smaxrow) {
257 nind = _NEWINDEX;
258 } else if (displaced) {
259 register struct ldat *pline = &CurScreen(sp)->_line[nind];
260 for (j = 0; j <= my_len; j++) {
261 int k = NewScreen(sp)->_maxx - j;
262 if (pline->text[j] != nline->text[j]
263 || pline->text[k] != nline->text[k]) {
264 nind = _NEWINDEX;
265 break;
266 }
267 }
268 }
269
270 nline->oldindex = nind;
271 }
272 #endif /* USE_SCROLL_HINTS */
273 oline->firstchar = oline->lastchar = _NOCHANGE;
274 if_USE_SCROLL_HINTS(oline->oldindex = i);
275 }
276
277 /*
278 * Clean up debris from scrolling or resizing the pad, so we do not
279 * accidentally pick up the index value during the next call to this
280 * procedure. The only rows that should have an index value are those
281 * that are displayed during this cycle.
282 */
283 #if USE_SCROLL_HINTS
284 for (i = pminrow - 1; (i >= 0) && (win->_line[i].oldindex >= 0); i--)
285 win->_line[i].oldindex = _NEWINDEX;
286 for (i = pmaxrow + 1; (i <= win->_maxy)
287 && (win->_line[i].oldindex >= 0); i++)
288 win->_line[i].oldindex = _NEWINDEX;
289 #endif
290
291 win->_begx = (NCURSES_SIZE_T) smincol;
292 win->_begy = (NCURSES_SIZE_T) sminrow;
293
294 if (win->_clear) {
295 win->_clear = FALSE;
296 NewScreen(sp)->_clear = TRUE;
297 }
298
299 /*
300 * Use the pad's current position, if it will be visible.
301 * If not, don't do anything; it is not an error.
302 */
303 if (win->_leaveok == FALSE
304 && win->_cury >= pminrow
305 && win->_curx >= pmincol
306 && win->_cury <= pmaxrow
307 && win->_curx <= pmaxcol) {
308 NewScreen(sp)->_cury = (NCURSES_SIZE_T) (win->_cury - pminrow
309 + win->_begy + win->_yoffset);
310 NewScreen(sp)->_curx = (NCURSES_SIZE_T) (win->_curx - pmincol
311 + win->_begx);
312 }
313 NewScreen(sp)->_leaveok = win->_leaveok;
314 win->_flags &= ~_HASMOVED;
315
316 /*
317 * Update our cache of the line-numbers that we displayed from the pad.
318 * We will use this on subsequent calls to this function to derive
319 * values to stuff into 'oldindex[]' -- for scrolling optimization.
320 */
321 win->_pad._pad_y = (NCURSES_SIZE_T) pminrow;
322 win->_pad._pad_x = (NCURSES_SIZE_T) pmincol;
323 win->_pad._pad_top = (NCURSES_SIZE_T) sminrow;
324 win->_pad._pad_left = (NCURSES_SIZE_T) smincol;
325 win->_pad._pad_bottom = (NCURSES_SIZE_T) smaxrow;
326 win->_pad._pad_right = (NCURSES_SIZE_T) smaxcol;
327
328 returnCode(OK);
329 }
330
331 NCURSES_EXPORT(int)
pechochar(WINDOW * pad,const chtype ch)332 pechochar(WINDOW *pad, const chtype ch)
333 {
334 T((T_CALLED("pechochar(%p, %s)"), (void *) pad, _tracechtype(ch)));
335
336 if (pad == 0)
337 returnCode(ERR);
338
339 if (!IS_PAD(pad))
340 returnCode(wechochar(pad, ch));
341
342 waddch(pad, ch);
343 prefresh(pad, pad->_pad._pad_y,
344 pad->_pad._pad_x,
345 pad->_pad._pad_top,
346 pad->_pad._pad_left,
347 pad->_pad._pad_bottom,
348 pad->_pad._pad_right);
349
350 returnCode(OK);
351 }
352