xref: /netbsd-src/lib/libcurses/resize.c (revision 6348e3f32a4431b45d07e1da16fd7b12725a45e7)
1 /*	$NetBSD: resize.c,v 1.37 2024/12/23 02:58:04 blymn Exp $	*/
2 
3 /*
4  * Copyright (c) 2001
5  *	Brett Lymn.
6  *
7  * This code has been donated to The NetBSD Foundation by the Author.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 #ifndef lint
33 #if 0
34 static char sccsid[] = "@(#)resize.c   blymn 2001/08/26";
35 #else
36 __RCSID("$NetBSD: resize.c,v 1.37 2024/12/23 02:58:04 blymn Exp $");
37 #endif
38 #endif				/* not lint */
39 
40 #include <stdlib.h>
41 
42 #include "curses.h"
43 #include "curses_private.h"
44 
45 static int __resizeterm(WINDOW *win, int nlines, int ncols);
46 static int __resizewin(WINDOW *win, int nlines, int ncols);
47 
48 /*
49  * wresize --
50  *	Resize the given window to the new size.
51  */
52 int
53 wresize(WINDOW *win, int req_nlines, int req_ncols)
54 {
55 	int	nlines = req_nlines;
56 	int	ncols = req_ncols;
57 
58 	if (__predict_false(win == NULL))
59 		return ERR;
60 
61 	__CTRACE(__CTRACE_WINDOW, "wresize: (%p, %d, %d)\n",
62 	    win, nlines, ncols);
63 	if (win->orig != NULL) {
64 		/* subwins must fit inside the parent - check this */
65 		if (win->begy > win->orig->begy + win->orig->maxy)
66 			win->begy = win->orig->begy + win->orig->maxy - 1;
67 		if (win->begy + nlines > win->orig->begy + win->orig->maxy)
68 			nlines = 0;
69 		if (nlines <= 0)
70 			nlines += win->orig->begy + win->orig->maxy - win->begy;
71 		if (nlines < 1)
72 			nlines = 1;
73 		if (win->begx > win->orig->begx + win->orig->maxx)
74 			win->begx = win->orig->begx + win->orig->maxx - 1;
75 		if (win->begx + ncols > win->orig->begx + win->orig->maxx)
76 			ncols = 0;
77 		if (ncols <= 0)
78 			ncols += win->orig->begx + win->orig->maxx - win->begx;
79 		if (ncols < 1)
80 			ncols = 1;
81 	} else if (!(win->flags & __ISPAD)) {
82 		/* bound "our" windows by the screen size */
83 		if (win == curscr || win == __virtscr || win == stdscr) {
84 			if (nlines > LINES)
85 				nlines = LINES;
86 			if (nlines < 1)
87 				nlines = 1;
88 			if (ncols > COLS)
89 				ncols = COLS;
90 			if (ncols < 1)
91 				ncols = 1;
92 		} else {
93 			if (win->begy > LINES)
94 				win->begy = 0;
95 			if (win->begy + nlines > LINES)
96 				nlines = 0;
97 			if (nlines <= 0)
98 				nlines += LINES - win->begy;
99 			if (nlines < 1)
100 				nlines = 1;
101 			if (win->begx > COLS)
102 				win->begx = 0;
103 			if (win->begx + ncols > COLS)
104 				ncols = 0;
105 			if (ncols <= 0)
106 				ncols += COLS - win->begx;
107 			if (ncols < 1)
108 				ncols = 1;
109 		}
110 	}
111 
112 	if ((__resizewin(win, nlines, ncols)) == ERR)
113 		return ERR;
114 
115 	win->reqy = req_nlines;
116 	win->reqx = req_ncols;
117 
118 	/* If someone resizes curscr, we must also resize __virtscr */
119 	if (win == curscr) {
120 		if ((__resizewin(__virtscr, nlines, ncols)) == ERR)
121 			return ERR;
122 		__virtscr->reqy = req_nlines;
123 		__virtscr->reqx = req_ncols;
124 	}
125 
126 	return OK;
127 }
128 
129 /*
130  * is_term_resized --
131  *	Return true if the given dimensions do not match the
132  *	internal structures.
133  */
134 bool
135 is_term_resized(int nlines, int ncols)
136 {
137 
138 	return (nlines > 0 && ncols > 0 &&
139 	    (nlines != _cursesi_screen->LINES ||
140 	    ncols != _cursesi_screen->COLS));
141 }
142 
143 /*
144  * resizeterm --
145  *	Resize the terminal window, resizing the dependent windows.
146  *	Handles internal book-keeping.
147  */
148 int
149 resizeterm(int nlines, int ncols)
150 {
151 	int result;
152 
153 	__CTRACE(__CTRACE_WINDOW, "resizeterm: (%d, %d)\n", nlines, ncols);
154 
155 	/* Unconditionally inform application screen has been resized. */
156 	_cursesi_screen->resized = 1;
157 
158 	if (!is_term_resized(nlines, ncols))
159 		return OK;
160 
161 	result = resize_term(nlines, ncols);
162 
163 	/* Screen contents are unknown, libcurses is not libpanel, we don't
164 	 * know the correct draw order. */
165 	clearok(curscr, TRUE);
166 
167 	if (result == OK) {
168 		/* Redraw the soft label keys to the new size. */
169 		__slk_resize(_cursesi_screen, ncols);
170 		__slk_noutrefresh(_cursesi_screen);
171 	}
172 
173 	return result;
174 }
175 
176 /*
177  * resize_term --
178  *	Resize the terminal window, resizing the dependent windows.
179  */
180 int
181 resize_term(int nlines, int ncols)
182 {
183 	WINDOW *win;
184 	struct __winlist *list;
185 	int rlines;
186 
187 	__CTRACE(__CTRACE_WINDOW, "resize_term: (%d, %d)\n", nlines, ncols);
188 
189 	if (!is_term_resized(nlines, ncols))
190 		return OK;
191 
192 	if (__resizeterm(curscr, nlines, ncols) == ERR)
193 		return ERR;
194 	if (__resizeterm(__virtscr, nlines, ncols) == ERR)
195 		return ERR;
196 	rlines = nlines - __rippedlines(_cursesi_screen, 0);
197 	if (__resizeterm(stdscr, rlines, ncols) == ERR)
198 		return ERR;
199 
200 	_cursesi_screen->LINES = nlines;
201 	_cursesi_screen->COLS = ncols;
202 	LINES = nlines;
203 	COLS = ncols;
204 
205 	/* tweak the flags now that we have updated the LINES and COLS */
206 	for (list = _cursesi_screen->winlistp; list != NULL; list = list->nextp) {
207 		win = list->winp;
208 
209 		if (!(win->flags & __ISPAD))
210 			__swflags(win);
211 	}
212 
213 	/* Resize and re-position the ripped off windows. */
214 	if (__ripoffresize(_cursesi_screen) == ERR)
215 		return ERR;
216 
217 	return OK;
218 }
219 
220 /*
221  * __resizeterm
222  *	Setup window for resizing.
223  */
224 static int
225 __resizeterm(WINDOW *win, int nlines, int ncols)
226 {
227 	int newlines, newcols;
228 
229 	newlines = win->reqy;
230 	if (win->begy + newlines >= nlines)
231 		newlines = 0;
232 	if (newlines == 0)
233 		newlines = nlines - win->begy;
234 
235 	newcols = win->reqx;
236 	if (win->begx + newcols >= ncols)
237 		newcols = 0;
238 	if (newcols == 0)
239 		newcols = ncols - win->begx;
240 
241 	return __resizewin(win, newlines, newcols);
242 }
243 
244 /*
245  * __resizewin --
246  *	Resize the given window.
247  */
248 static int
249 __resizewin(WINDOW *win, int nlines, int ncols)
250 {
251 	__LINE			*lp, *olp, **newlines, *newlspace;
252 	__LDATA			*sp;
253 	__LDATA			*newwspace;
254 	int			 i, j;
255 	int			 y, x;
256 	WINDOW			*swin;
257 
258 	__CTRACE(__CTRACE_WINDOW, "resize: (%p, %d, %d)\n", win, nlines, ncols);
259 	__CTRACE(__CTRACE_WINDOW, "resize: win->wattr = %08x\n", win->wattr);
260 	__CTRACE(__CTRACE_WINDOW, "resize: win->flags = %#.4x\n", win->flags);
261 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxy = %d\n", win->maxy);
262 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxx = %d\n", win->maxx);
263 	__CTRACE(__CTRACE_WINDOW, "resize: win->begy = %d\n", win->begy);
264 	__CTRACE(__CTRACE_WINDOW, "resize: win->begx = %d\n", win->begx);
265 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_t = %d\n", win->scr_t);
266 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_b = %d\n", win->scr_b);
267 
268 	/*
269 	 * free up any non-spacing storage before we lose the
270 	 * pointers...
271 	 */
272 #ifdef HAVE_WCHAR
273 	__cursesi_win_free_nsp(win);
274 #endif
275 
276 	if (nlines <= 0 || ncols <= 0)
277 		nlines = ncols = 0;
278 	else {
279 		/* Reallocate line pointer array and line space. */
280 		newlines = realloc(win->alines, nlines * sizeof(__LINE *));
281 		if (newlines == NULL)
282 			return ERR;
283 		win->alines = newlines;
284 
285 		newlspace = realloc(win->lspace, nlines * sizeof(__LINE));
286 		if (newlspace == NULL)
287 			return ERR;
288 		win->lspace = newlspace;
289 	}
290 
291 	/* Don't allocate window and line space if it's a subwindow */
292 	if (win->orig == NULL) {
293 		/*
294 		 * Allocate window space in one chunk.
295 		 */
296 		if (ncols != 0) {
297 			newwspace = realloc(win->wspace,
298 					    ncols * nlines * sizeof(__LDATA));
299 			if (newwspace == NULL)
300 				return ERR;
301 			win->wspace = newwspace;
302 		}
303 
304 		/*
305 		 * Point line pointers to line space, and lines themselves into
306 		 * window space.
307 		 */
308 		for (lp = win->lspace, i = 0; i < nlines; i++, lp++) {
309 			win->alines[i] = lp;
310 			lp->line = &win->wspace[i * ncols];
311 #ifdef DEBUG
312 			lp->sentinel = SENTINEL_VALUE;
313 #endif
314 			lp->firstchp = &lp->firstch;
315 			lp->lastchp = &lp->lastch;
316 			lp->firstch = 0;
317 			lp->lastch = ncols - 1;
318 			lp->flags = __ISDIRTY;
319 		}
320 	} else {
321 
322 		win->ch_off = win->begx - win->orig->begx;
323 		  /* Point line pointers to line space. */
324 		for (lp = win->lspace, i = 0; i < nlines; i++, lp++) {
325 			win->alines[i] = lp;
326 			olp = win->orig->alines[i + win->begy - win->orig->begy];
327 			lp->line = &olp->line[win->ch_off];
328 #ifdef DEBUG
329 			lp->sentinel = SENTINEL_VALUE;
330 #endif
331 			lp->firstchp = &olp->firstch;
332 			lp->lastchp = &olp->lastch;
333 			lp->flags = __ISDIRTY;
334 		}
335 	}
336 
337 	win->cury = win->curx = 0;
338 	win->maxy = nlines;
339 	win->maxx = ncols;
340 	win->scr_b = win->maxy - 1;
341 	__swflags(win);
342 
343 	  /*
344 	   * we must zot the window contents otherwise lines may pick
345 	   * up attributes from the previous line when the window is
346 	   * made smaller.  The client will redraw the window anyway
347 	   * so this is no big deal.
348 	   */
349 	for (i = 0; i < win->maxy; i++) {
350 		lp = win->alines[i];
351 		for (sp = lp->line, j = 0; j < win->maxx; j++, sp++) {
352 			sp->attr = 0;
353 			sp->cflags = CA_BACKGROUND;
354 #ifndef HAVE_WCHAR
355 			sp->ch = win->bch;
356 #else
357 			sp->ch = (wchar_t)btowc((int)win->bch);
358 			sp->nsp = NULL;
359 			if (_cursesi_copy_nsp(win->bnsp, sp) == ERR)
360 				return ERR;
361 			sp->wcols = 1;
362 #endif /* HAVE_WCHAR */
363 		}
364 		lp->hash = __hash_line(lp->line, ncols);
365 	}
366 
367 	__CTRACE(__CTRACE_WINDOW, "resize: win->wattr = %08x\n", win->wattr);
368 	__CTRACE(__CTRACE_WINDOW, "resize: win->flags = %#.4x\n", win->flags);
369 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxy = %d\n", win->maxy);
370 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxx = %d\n", win->maxx);
371 	__CTRACE(__CTRACE_WINDOW, "resize: win->begy = %d\n", win->begy);
372 	__CTRACE(__CTRACE_WINDOW, "resize: win->begx = %d\n", win->begx);
373 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_t = %d\n", win->scr_t);
374 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_b = %d\n", win->scr_b);
375 
376 	if (win->orig == NULL) {
377 		/* bound subwindows to new size and fixup their pointers */
378 		for (swin = win->nextp; swin != win; swin = swin->nextp) {
379 			y = swin->reqy;
380 			if (swin->begy > win->begy + win->maxy)
381 				swin->begy = win->begy + win->maxy - 1;
382 			if (swin->begy + y > win->begy + win->maxy)
383 				y = 0;
384 			if (y <= 0)
385 				y += win->begy + win->maxy - swin->begy;
386 			if (y < 1)
387 				y = 1;
388 			x = swin->reqx;
389 			if (swin->begx > win->begx + win->maxx)
390 				swin->begx = win->begx + win->maxx - 1;
391 			if (swin->begx + x > win->begx + win->maxx)
392 				x = 0;
393 			if (x <= 0)
394 				x += win->begx + win->maxx - swin->begx;
395 			if (x < 1)
396 				x = 1;
397 			__resizewin(swin, y, x);
398 		}
399 	}
400 
401 	return OK;
402 }
403