xref: /netbsd-src/lib/libcurses/resize.c (revision 501cd18a74d52bfcca7d9e7e3b0d472bbc870558)
1 /*	$NetBSD: resize.c,v 1.24 2017/01/10 23:28:45 roy 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  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 #ifndef lint
40 #if 0
41 static char sccsid[] = "@(#)resize.c   blymn 2001/08/26";
42 #else
43 __RCSID("$NetBSD: resize.c,v 1.24 2017/01/10 23:28:45 roy Exp $");
44 #endif
45 #endif				/* not lint */
46 
47 #include <stdlib.h>
48 
49 #include "curses.h"
50 #include "curses_private.h"
51 
52 static int __resizeterm(WINDOW *win, int nlines, int ncols);
53 static int __resizewin(WINDOW *win, int nlines, int ncols);
54 
55 /*
56  * wresize --
57  *	Resize the given window to the new size.
58  */
59 int
60 wresize(WINDOW *win, int req_nlines, int req_ncols)
61 {
62 	int	nlines = req_nlines;
63 	int	ncols = req_ncols;
64 
65 	if (win == NULL)
66 		return ERR;
67 
68 #ifdef	DEBUG
69 	__CTRACE(__CTRACE_WINDOW, "wresize: (%p, %d, %d)\n",
70 	    win, nlines, ncols);
71 #endif
72 	if (win->orig == NULL) {
73 		/* bound "our" windows by the screen size */
74 		if (win == curscr || win == __virtscr || win == stdscr) {
75 			if (nlines > LINES)
76 				nlines = LINES;
77 			if (nlines < 1)
78 				nlines = 1;
79 			if (ncols > COLS)
80 				ncols = COLS;
81 			if (ncols < 1)
82 				ncols = 1;
83 		} else {
84 			if (win->begy > LINES)
85 				win->begy = 0;
86 			if (win->begy + nlines > LINES)
87 				nlines = 0;
88 			if (nlines <= 0)
89 				nlines += LINES - win->begy;
90 			if (nlines < 1)
91 				nlines = 1;
92 			if (win->begx > COLS)
93 				win->begx = 0;
94 			if (win->begx + ncols > COLS)
95 				ncols = 0;
96 			if (ncols <= 0)
97 				ncols += COLS - win->begx;
98 			if (ncols < 1)
99 				ncols = 1;
100 		}
101 	} else {
102 		/* subwins must fit inside the parent - check this */
103 		if (win->begy > win->orig->begy + win->orig->maxy)
104 			win->begy = win->orig->begy + win->orig->maxy - 1;
105 		if (win->begy + nlines > win->orig->begy + win->orig->maxy)
106 			nlines = 0;
107 		if (nlines <= 0)
108 			nlines += win->orig->begy + win->orig->maxy - win->begy;
109 		if (nlines < 1)
110 			nlines = 1;
111 		if (win->begx > win->orig->begx + win->orig->maxx)
112 			win->begx = win->orig->begx + win->orig->maxx - 1;
113 		if (win->begx + ncols > win->orig->begx + win->orig->maxx)
114 			ncols = 0;
115 		if (ncols <= 0)
116 			ncols += win->orig->begx + win->orig->maxx - win->begx;
117 		if (ncols < 1)
118 			ncols = 1;
119 	}
120 
121 	if ((__resizewin(win, nlines, ncols)) == ERR)
122 		return ERR;
123 
124 	win->reqy = req_nlines;
125 	win->reqx = req_ncols;
126 
127 	/* If someone resizes curscr, we must also resize __virtscr */
128 	if (win == curscr) {
129 		if ((__resizewin(__virtscr, nlines, ncols)) == ERR)
130 			return ERR;
131 		__virtscr->reqy = req_nlines;
132 		__virtscr->reqx = req_ncols;
133 	}
134 
135 	return OK;
136 }
137 
138 /*
139  * is_term_resized --
140  *	Return true if the given dimensions do not match the
141  *	internal structures.
142  */
143 bool
144 is_term_resized(int nlines, int ncols)
145 {
146 
147 	return (nlines > 0 && ncols > 0 &&
148 	    (nlines != _cursesi_screen->LINES ||
149 	    ncols != _cursesi_screen->COLS));
150 }
151 
152 /*
153  * resizeterm --
154  *	Resize the terminal window, resizing the dependent windows.
155  *	Handles internal book-keeping.
156  */
157 int
158 resizeterm(int nlines, int ncols)
159 {
160 	int result;
161 
162 #ifdef	DEBUG
163 	__CTRACE(__CTRACE_WINDOW, "resizeterm: (%d, %d)\n", nlines, ncols);
164 #endif
165 
166 	if (!is_term_resized(nlines, ncols))
167 		return OK;
168 
169 	result = resize_term(nlines, ncols);
170 	clearok(curscr, TRUE);
171 	return result;
172 }
173 
174 /*
175  * resize_term --
176  *	Resize the terminal window, resizing the dependent windows.
177  */
178 int
179 resize_term(int nlines, int ncols)
180 {
181 	WINDOW *win;
182 	struct __winlist *list;
183 
184 #ifdef	DEBUG
185 	__CTRACE(__CTRACE_WINDOW, "resize_term: (%d, %d)\n", nlines, ncols);
186 #endif
187 
188 	if (!is_term_resized(nlines, ncols))
189 		return OK;
190 
191 	if (__resizeterm(curscr, nlines, ncols) == ERR)
192 		return ERR;
193 	if (__resizeterm(__virtscr, nlines, ncols) == ERR)
194 		return ERR;
195 	nlines -= _cursesi_screen->ripped_top - _cursesi_screen->ripped_bottom;
196 	if (__resizeterm(stdscr, nlines, ncols) == ERR)
197 		return ERR;
198 
199 	LINES = nlines;
200 	COLS = ncols;
201 
202 	  /* tweak the flags now that we have updated the LINES and COLS */
203 	for (list = _cursesi_screen->winlistp; list != NULL; list = list->nextp) {
204 		win = list->winp;
205 
206 		if (!(win->flags & __ISPAD))
207 			__swflags(win);
208 	}
209 
210 	return OK;
211 }
212 
213 /*
214  * __resizeterm
215  *	Setup window for resizing.
216  */
217 static int
218 __resizeterm(WINDOW *win, int nlines, int ncols)
219 {
220 	int newlines, newcols;
221 
222 	newlines = win->reqy;
223 	if (win->begy + newlines >= nlines)
224 		newlines = 0;
225 	if (newlines == 0)
226 		newlines = nlines - win->begy;
227 
228 	newcols = win->reqx;
229 	if (win->begx + newcols >= ncols)
230 		newcols = 0;
231 	if (newcols == 0)
232 		newcols = ncols - win->begx;
233 
234 	return __resizewin(win, newlines, newcols);
235 }
236 
237 /*
238  * __resizewin --
239  *	Resize the given window.
240  */
241 static int
242 __resizewin(WINDOW *win, int nlines, int ncols)
243 {
244 	__LINE			*lp, *olp, **newlines, *newlspace;
245 	__LDATA			*sp;
246 	__LDATA			*newwspace;
247 	int			 i, j;
248 	int			 y, x;
249 	WINDOW			*swin;
250 
251 #ifdef	DEBUG
252 	__CTRACE(__CTRACE_WINDOW, "resize: (%p, %d, %d)\n", win, nlines, ncols);
253 	__CTRACE(__CTRACE_WINDOW, "resize: win->wattr = %08x\n", win->wattr);
254 	__CTRACE(__CTRACE_WINDOW, "resize: win->flags = %#.4x\n", win->flags);
255 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxy = %d\n", win->maxy);
256 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxx = %d\n", win->maxx);
257 	__CTRACE(__CTRACE_WINDOW, "resize: win->begy = %d\n", win->begy);
258 	__CTRACE(__CTRACE_WINDOW, "resize: win->begx = %d\n", win->begx);
259 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_t = %d\n", win->scr_t);
260 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_b = %d\n", win->scr_b);
261 #endif
262 
263 	/*
264 	 * free up any non-spacing storage before we lose the
265 	 * pointers...
266 	 */
267 #ifdef HAVE_WCHAR
268 	__cursesi_win_free_nsp(win);
269 #endif
270 
271 	if (nlines <= 0 || ncols <= 0)
272 		nlines = ncols = 0;
273 	else {
274 		/* Reallocate line pointer array and line space. */
275 		newlines = realloc(win->alines, nlines * sizeof(__LINE *));
276 		if (newlines == NULL)
277 			return ERR;
278 		win->alines = newlines;
279 
280 		newlspace = realloc(win->lspace, nlines * sizeof(__LINE));
281 		if (newlspace == NULL)
282 			return ERR;
283 		win->lspace = newlspace;
284 	}
285 
286 	/* Don't allocate window and line space if it's a subwindow */
287 	if (win->orig == NULL) {
288 		/*
289 		 * Allocate window space in one chunk.
290 		 */
291 		if (ncols != 0) {
292 			newwspace = realloc(win->wspace,
293 					    ncols * nlines * sizeof(__LDATA));
294 			if (newwspace == NULL)
295 				return ERR;
296 			win->wspace = newwspace;
297 		}
298 
299 		/*
300 		 * Point line pointers to line space, and lines themselves into
301 		 * window space.
302 		 */
303 		for (lp = win->lspace, i = 0; i < nlines; i++, lp++) {
304 			win->alines[i] = lp;
305 			lp->line = &win->wspace[i * ncols];
306 #ifdef DEBUG
307 			lp->sentinel = SENTINEL_VALUE;
308 #endif
309 			lp->firstchp = &lp->firstch;
310 			lp->lastchp = &lp->lastch;
311 			lp->firstch = 0;
312 			lp->lastch = ncols - 1;
313 			lp->flags = __ISDIRTY;
314 		}
315 	} else {
316 
317 		win->ch_off = win->begx - win->orig->begx;
318 		  /* Point line pointers to line space. */
319 		for (lp = win->lspace, i = 0; i < nlines; i++, lp++) {
320 			win->alines[i] = lp;
321 			olp = win->orig->alines[i + win->begy - win->orig->begy];
322 			lp->line = &olp->line[win->ch_off];
323 #ifdef DEBUG
324 			lp->sentinel = SENTINEL_VALUE;
325 #endif
326 			lp->firstchp = &olp->firstch;
327 			lp->lastchp = &olp->lastch;
328 			lp->flags = __ISDIRTY;
329 		}
330 	}
331 
332 	win->cury = win->curx = 0;
333 	win->maxy = nlines;
334 	win->maxx = ncols;
335 	win->scr_b = win->maxy - 1;
336 	__swflags(win);
337 
338 	  /*
339 	   * we must zot the window contents otherwise lines may pick
340 	   * up attributes from the previous line when the window is
341 	   * made smaller.  The client will redraw the window anyway
342 	   * so this is no big deal.
343 	   */
344 	for (i = 0; i < win->maxy; i++) {
345 		lp = win->alines[i];
346 		for (sp = lp->line, j = 0; j < win->maxx; j++, sp++) {
347 			sp->attr = 0;
348 #ifndef HAVE_WCHAR
349 			sp->ch = win->bch;
350 #else
351 			sp->ch = (wchar_t)btowc((int)win->bch);
352 			sp->nsp = NULL;
353 			if (_cursesi_copy_nsp(win->bnsp, sp) == ERR)
354 				return ERR;
355 			SET_WCOL(*sp, 1);
356 #endif /* HAVE_WCHAR */
357 		}
358 		lp->hash = __hash((char *)(void *)lp->line,
359 				  (size_t)(ncols * __LDATASIZE));
360 	}
361 
362 #ifdef DEBUG
363 	__CTRACE(__CTRACE_WINDOW, "resize: win->wattr = %08x\n", win->wattr);
364 	__CTRACE(__CTRACE_WINDOW, "resize: win->flags = %#.4x\n", win->flags);
365 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxy = %d\n", win->maxy);
366 	__CTRACE(__CTRACE_WINDOW, "resize: win->maxx = %d\n", win->maxx);
367 	__CTRACE(__CTRACE_WINDOW, "resize: win->begy = %d\n", win->begy);
368 	__CTRACE(__CTRACE_WINDOW, "resize: win->begx = %d\n", win->begx);
369 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_t = %d\n", win->scr_t);
370 	__CTRACE(__CTRACE_WINDOW, "resize: win->scr_b = %d\n", win->scr_b);
371 #endif
372 
373 	if (win->orig == NULL) {
374 		/* bound subwindows to new size and fixup their pointers */
375 		for (swin = win->nextp; swin != win; swin = swin->nextp) {
376 			y = swin->reqy;
377 			if (swin->begy > win->begy + win->maxy)
378 				swin->begy = win->begy + win->maxy - 1;
379 			if (swin->begy + y > win->begy + win->maxy)
380 				y = 0;
381 			if (y <= 0)
382 				y += win->begy + win->maxy - swin->begy;
383 			if (y < 1)
384 				y = 1;
385 			x = swin->reqx;
386 			if (swin->begx > win->begx + win->maxx)
387 				swin->begx = win->begx + win->maxx - 1;
388 			if (swin->begx + x > win->begx + win->maxx)
389 				x = 0;
390 			if (x <= 0)
391 				x += win->begy + win->maxx - swin->begx;
392 			if (x < 1)
393 				x = 1;
394 			__resizewin(swin, y, x);
395 		}
396 	}
397 
398 	return OK;
399 }
400