1/****************************************************************************
2 * Copyright 2020 Thomas E. Dickey                                          *
3 * Copyright 1998-2015,2016 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: Thomas E. Dickey                                                *
32 *     and: Juergen Pfeifer                                                 *
33 ****************************************************************************/
34
35/*
36 * This is an extension to the curses library.  It provides callers with a hook
37 * into the NCURSES data to resize windows, primarily for use by programs
38 * running in an X Window terminal (e.g., xterm).  I abstracted this module
39 * from my application library for NCURSES because it must be compiled with
40 * the private data structures -- T.Dickey 1995/7/4.
41 */
42
43#include <curses.priv.h>
44
45#ifndef CUR
46#define CUR SP_TERMTYPE
47#endif
48
49MODULE_ID("$Id: resizeterm.c,v 1.50 2020/02/02 23:34:34 tom Exp $")
50
51/*
52 * If we're trying to be reentrant, do not want any local statics.
53 */
54#if USE_REENTRANT
55#define EXTRA_ARGS ,     CurLines,     CurCols
56#define EXTRA_DCLS , int CurLines, int CurCols
57#else
58static int current_lines;
59static int current_cols;
60#define CurLines current_lines
61#define CurCols  current_cols
62#define EXTRA_ARGS		/* nothing */
63#define EXTRA_DCLS		/* nothing */
64#endif
65
66#if NCURSES_SP_FUNCS && !defined(USE_SP_WINDOWLIST)
67#define UNUSED_SP  (void) sp
68#else
69#define UNUSED_SP		/* nothing */
70#endif
71
72#ifdef TRACE
73static void
74show_window_sizes(const char *name)
75{
76    SCREEN *sp;
77    WINDOWLIST *wp;
78
79    _nc_lock_global(curses);
80    for (each_screen(sp)) {
81	_tracef("%s resizing: %p: %2d x %2d (%2d x %2d)", name, (void *) sp,
82		*(ptrLines(sp)),
83		*(ptrCols(sp)),
84		screen_lines(sp), screen_columns(sp));
85	for (each_window(sp, wp)) {
86	    _tracef("  window %p is %2ld x %2ld at %2ld,%2ld",
87		    (void *) &(wp->win),
88		    (long) wp->win._maxy + 1,
89		    (long) wp->win._maxx + 1,
90		    (long) wp->win._begy,
91		    (long) wp->win._begx);
92	}
93    }
94    _nc_unlock_global(curses);
95}
96#endif
97
98/*
99 * Return true if the given dimensions do not match the internal terminal
100 * structure's size.
101 */
102NCURSES_EXPORT(bool)
103NCURSES_SP_NAME(is_term_resized) (NCURSES_SP_DCLx int ToLines, int ToCols)
104{
105    T((T_CALLED("is_term_resized(%p, %d, %d)"), (void *) SP_PARM, ToLines, ToCols));
106    returnCode(ToLines > 0
107	       && ToCols > 0
108	       && (ToLines != screen_lines(SP_PARM)
109		   || ToCols != screen_columns(SP_PARM)));
110}
111
112#if NCURSES_SP_FUNCS
113NCURSES_EXPORT(bool)
114is_term_resized(int ToLines, int ToCols)
115{
116    return NCURSES_SP_NAME(is_term_resized) (CURRENT_SCREEN, ToLines, ToCols);
117}
118#endif
119
120/*
121 */
122static ripoff_t *
123ripped_window(WINDOW *win)
124{
125    ripoff_t *result = 0;
126    ripoff_t *rop;
127
128    if (win != 0) {
129#ifdef USE_SP_RIPOFF
130	SCREEN *sp = _nc_screen_of(win);
131#endif
132	for (each_ripoff(rop)) {
133	    if (rop->win == win && rop->line != 0) {
134		result = rop;
135		break;
136	    }
137	}
138    }
139    return result;
140}
141
142/*
143 * Returns the number of lines from the bottom for the beginning of a ripped
144 * off window.
145 */
146static int
147ripped_bottom(WINDOW *win)
148{
149    int result = 0;
150
151    if (win != 0) {
152	ripoff_t *rop;
153
154#ifdef USE_SP_RIPOFF
155	SCREEN *sp = _nc_screen_of(win);
156#endif
157	for (each_ripoff(rop)) {
158	    if (rop->line < 0) {
159		result -= rop->line;
160		if (rop->win == win) {
161		    break;
162		}
163	    }
164	}
165    }
166    return result;
167}
168
169/*
170 * Return the number of levels of child-windows under the current window.
171 */
172static int
173child_depth(WINDOW *cmp)
174{
175    int depth = 0;
176
177    if (cmp != 0) {
178#ifdef USE_SP_WINDOWLIST
179	SCREEN *sp = _nc_screen_of(cmp);
180#endif
181	WINDOWLIST *wp;
182
183	for (each_window(sp, wp)) {
184	    WINDOW *tst = &(wp->win);
185	    if (tst->_parent == cmp) {
186		depth = 1 + child_depth(tst);
187		break;
188	    }
189	}
190    }
191    return depth;
192}
193
194/*
195 * Return the number of levels of parent-windows above the current window.
196 */
197static int
198parent_depth(WINDOW *cmp)
199{
200    int depth = 0;
201
202    if (cmp != 0) {
203	WINDOW *tst;
204	while ((tst = cmp->_parent) != 0) {
205	    ++depth;
206	    cmp = tst;
207	}
208    }
209    return depth;
210}
211
212/*
213 * FIXME: must adjust position so it's within the parent!
214 */
215static int
216adjust_window(WINDOW *win, int ToLines, int ToCols, int stolen EXTRA_DCLS)
217{
218    int result;
219    int bottom = CurLines + _nc_screen_of(win)->_topstolen - stolen;
220    int myLines = win->_maxy + 1;
221    int myCols = win->_maxx + 1;
222    ripoff_t *rop = ripped_window(win);
223
224    T((T_CALLED("adjust_window(%p,%d,%d)%s depth %d/%d currently %ldx%ld at %ld,%ld"),
225       (void *) win, ToLines, ToCols,
226       (rop != 0) ? " (rip)" : "",
227       parent_depth(win),
228       child_depth(win),
229       (long) getmaxy(win), (long) getmaxx(win),
230       (long) getbegy(win) + win->_yoffset, (long) getbegx(win)));
231
232    if (rop != 0 && rop->line < 0) {
233	/*
234	 * If it is a ripped-off window at the bottom of the screen, simply
235	 * move it to the same relative position.
236	 */
237	win->_begy = (NCURSES_SIZE_T) (ToLines - ripped_bottom(win) - 0 - win->_yoffset);
238	if (rop->hook == _nc_slk_initialize)
239	    _nc_format_slks(
240#if NCURSES_SP_FUNCS
241			       _nc_screen_of(win),
242#endif
243			       ToCols);
244    } else if (win->_begy >= bottom) {
245	/*
246	 * If it is below the bottom of the new screen, move up by the same
247	 * amount that the screen shrank.
248	 */
249	win->_begy = (NCURSES_SIZE_T) (win->_begy + (ToLines - CurLines));
250    } else {
251	if (myLines == (CurLines - stolen)
252	    && ToLines != CurLines) {
253	    myLines = ToLines - stolen;
254	} else if (myLines == CurLines
255		   && ToLines != CurLines) {
256	    myLines = ToLines;
257	}
258    }
259
260    if (myLines > ToLines) {
261	myLines = ToLines;
262    }
263
264    if (myCols > ToCols)
265	myCols = ToCols;
266
267    if (myCols == CurCols
268	&& ToCols != CurCols)
269	myCols = ToCols;
270
271    result = wresize(win, myLines, myCols);
272    returnCode(result);
273}
274
275/*
276 * If we're decreasing size, recursively search for windows that have no
277 * children, decrease those to fit, then decrease the containing window, etc.
278 */
279static int
280decrease_size(NCURSES_SP_DCLx int ToLines, int ToCols, int stolen EXTRA_DCLS)
281{
282    bool found;
283    int depth = 0;
284    WINDOWLIST *wp;
285
286    T((T_CALLED("decrease_size(%p, %d, %d)"), (void *) SP_PARM, ToLines, ToCols));
287    UNUSED_SP;
288
289    do {
290	found = FALSE;
291	TR(TRACE_UPDATE, ("decreasing size of windows to %dx%d, depth=%d",
292			  ToLines, ToCols, depth));
293	for (each_window(SP_PARM, wp)) {
294	    WINDOW *win = &(wp->win);
295
296	    if (!(win->_flags & _ISPAD)) {
297		if (child_depth(win) == depth) {
298		    found = TRUE;
299		    if (adjust_window(win, ToLines, ToCols,
300				      stolen EXTRA_ARGS) != OK)
301			returnCode(ERR);
302		}
303	    }
304	}
305	++depth;
306    } while (found);
307    returnCode(OK);
308}
309
310/*
311 * If we're increasing size, recursively search for windows that have no
312 * parent, increase those to fit, then increase the contained window, etc.
313 */
314static int
315increase_size(NCURSES_SP_DCLx int ToLines, int ToCols, int stolen EXTRA_DCLS)
316{
317    bool found;
318    int depth = 0;
319    WINDOWLIST *wp;
320
321    T((T_CALLED("increase_size(%p, %d, %d)"), (void *) SP_PARM, ToLines, ToCols));
322    UNUSED_SP;
323
324    do {
325	found = FALSE;
326	TR(TRACE_UPDATE, ("increasing size of windows to %dx%d, depth=%d",
327			  ToLines, ToCols, depth));
328	for (each_window(SP_PARM, wp)) {
329	    WINDOW *win = &(wp->win);
330
331	    if (!(win->_flags & _ISPAD)) {
332		if (parent_depth(win) == depth) {
333		    found = TRUE;
334		    if (adjust_window(win, ToLines, ToCols,
335				      stolen EXTRA_ARGS) != OK)
336			returnCode(ERR);
337		}
338	    }
339	}
340	++depth;
341    } while (found);
342    returnCode(OK);
343}
344
345/*
346 * This function reallocates NCURSES window structures, with no side-effects
347 * such as ungetch().
348 */
349NCURSES_EXPORT(int)
350NCURSES_SP_NAME(resize_term) (NCURSES_SP_DCLx int ToLines, int ToCols)
351{
352    int result = OK EXTRA_ARGS;
353    int was_stolen;
354
355    T((T_CALLED("resize_term(%p,%d,%d) old(%d,%d)"),
356       (void *) SP_PARM, ToLines, ToCols,
357       (SP_PARM == 0) ? -1 : screen_lines(SP_PARM),
358       (SP_PARM == 0) ? -1 : screen_columns(SP_PARM)));
359
360    if (SP_PARM == 0 || ToLines <= 0 || ToCols <= 0) {
361	returnCode(ERR);
362    }
363
364    _nc_nonsp_lock_global(curses);
365
366    was_stolen = (screen_lines(SP_PARM) - SP_PARM->_lines_avail);
367    if (NCURSES_SP_NAME(is_term_resized) (NCURSES_SP_ARGx ToLines, ToCols)) {
368	int myLines = CurLines = screen_lines(SP_PARM);
369	int myCols = CurCols = screen_columns(SP_PARM);
370
371#ifdef TRACE
372	if (USE_TRACEF(TRACE_UPDATE)) {
373	    show_window_sizes("before");
374	    _nc_unlock_global(tracef);
375	}
376#endif
377	if (ToLines > screen_lines(SP_PARM)) {
378	    result = increase_size(NCURSES_SP_ARGx
379				   myLines = ToLines,
380				   myCols,
381				   was_stolen EXTRA_ARGS);
382	    CurLines = myLines;
383	    CurCols = myCols;
384	}
385
386	if ((result == OK)
387	    && (ToCols > screen_columns(SP_PARM))) {
388	    result = increase_size(NCURSES_SP_ARGx
389				   myLines,
390				   myCols = ToCols,
391				   was_stolen EXTRA_ARGS);
392	    CurLines = myLines;
393	    CurCols = myCols;
394	}
395
396	if ((result == OK)
397	    && (ToLines < myLines ||
398		ToCols < myCols)) {
399	    result = decrease_size(NCURSES_SP_ARGx
400				   ToLines,
401				   ToCols,
402				   was_stolen EXTRA_ARGS);
403	}
404
405	if (result == OK) {
406	    screen_lines(SP_PARM) = (NCURSES_SIZE_T) ToLines;
407	    screen_columns(SP_PARM) = (NCURSES_SIZE_T) ToCols;
408
409#ifdef USE_TERM_DRIVER
410	    CallDriver_2(SP_PARM, td_setsize, ToLines, ToCols);
411#else
412	    lines = (NCURSES_SIZE_T) ToLines;
413	    columns = (NCURSES_SIZE_T) ToCols;
414#endif
415
416	    SP_PARM->_lines_avail = (NCURSES_SIZE_T) (ToLines - was_stolen);
417
418	    if (SP_PARM->oldhash) {
419		FreeAndNull(SP_PARM->oldhash);
420	    }
421	    if (SP_PARM->newhash) {
422		FreeAndNull(SP_PARM->newhash);
423	    }
424#ifdef TRACE
425	    if (USE_TRACEF(TRACE_UPDATE)) {
426		SET_LINES(ToLines - was_stolen);
427		SET_COLS(ToCols);
428		show_window_sizes("after");
429		_nc_unlock_global(tracef);
430	    }
431#endif
432	}
433    }
434
435    if (result == OK) {
436	/*
437	 * Always update LINES, to allow for call from lib_doupdate.c which
438	 * needs to have the count adjusted by the stolen (ripped off) lines.
439	 */
440	SET_LINES(ToLines - was_stolen);
441	SET_COLS(ToCols);
442    }
443
444    _nc_nonsp_unlock_global(curses);
445
446    returnCode(result);
447}
448
449#if NCURSES_SP_FUNCS
450NCURSES_EXPORT(int)
451resize_term(int ToLines, int ToCols)
452{
453    int res;
454    _nc_sp_lock_global(curses);
455    res = NCURSES_SP_NAME(resize_term) (CURRENT_SCREEN, ToLines, ToCols);
456    _nc_sp_unlock_global(curses);
457    return (res);
458}
459#endif
460
461/*
462 * This function reallocates NCURSES window structures.  It is invoked in
463 * response to a SIGWINCH interrupt.  Other user-defined windows may also need
464 * to be reallocated.
465 *
466 * Because this performs memory allocation, it should not (in general) be
467 * invoked directly from the signal handler.
468 */
469NCURSES_EXPORT(int)
470NCURSES_SP_NAME(resizeterm) (NCURSES_SP_DCLx int ToLines, int ToCols)
471{
472    int result = ERR;
473
474    T((T_CALLED("resizeterm(%p, %d,%d) old(%d,%d)"),
475       (void *) SP_PARM, ToLines, ToCols,
476       (SP_PARM == 0) ? -1 : screen_lines(SP_PARM),
477       (SP_PARM == 0) ? -1 : screen_columns(SP_PARM)));
478
479    if (SP_PARM != 0 && ToLines > 0 && ToCols > 0) {
480	result = OK;
481	SP_PARM->_sig_winch = FALSE;
482
483	if (NCURSES_SP_NAME(is_term_resized) (NCURSES_SP_ARGx ToLines, ToCols)) {
484#if USE_SIGWINCH
485	    ripoff_t *rop;
486	    bool slk_visible = (SP_PARM != 0
487				&& SP_PARM->_slk != 0
488				&& !(SP_PARM->_slk->hidden));
489
490	    if (slk_visible) {
491		slk_clear();
492	    }
493#endif
494	    result = NCURSES_SP_NAME(resize_term) (NCURSES_SP_ARGx ToLines, ToCols);
495
496#if USE_SIGWINCH
497	    clearok(CurScreen(SP_PARM), TRUE);	/* screen contents are unknown */
498
499	    /* ripped-off lines are a special case: if we did not lengthen
500	     * them, we haven't moved them either.  repaint them, too.
501	     *
502	     * for the rest - stdscr and other windows - the client has to
503	     * decide which to repaint, since without panels, ncurses does
504	     * not know which are really on top.
505	     */
506	    for (each_ripoff(rop)) {
507		if (rop->win != StdScreen(SP_PARM)
508		    && rop->win != 0
509		    && rop->line < 0) {
510
511		    if (rop->hook != _nc_slk_initialize) {
512			touchwin(rop->win);
513			wnoutrefresh(rop->win);
514		    }
515		}
516	    }
517
518	    /* soft-keys are a special case: we _know_ how to repaint them */
519	    if (slk_visible) {
520		NCURSES_SP_NAME(slk_restore) (NCURSES_SP_ARG);
521		NCURSES_SP_NAME(slk_touch) (NCURSES_SP_ARG);
522		NCURSES_SP_NAME(slk_refresh) (NCURSES_SP_ARG);
523	    }
524#endif
525	}
526#if USE_SIGWINCH
527	safe_ungetch(SP_PARM, KEY_RESIZE);	/* so application can know this */
528#endif
529    }
530
531    returnCode(result);
532}
533
534#if NCURSES_SP_FUNCS
535NCURSES_EXPORT(int)
536resizeterm(int ToLines, int ToCols)
537{
538    return NCURSES_SP_NAME(resizeterm) (CURRENT_SCREEN, ToLines, ToCols);
539}
540#endif
541