xref: /vim-8.2.3635/src/window.c (revision ceb56ddb)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  *
5  * Do ":help uganda"  in Vim to read a list of people who contributed.
6  * Do ":help credits" in Vim to see a list of people who contributed.
7  * See README.txt for an overview of the Vim source code.
8  */
9 
10 #include "vim.h"
11 
12 static void cmd_with_count(char *cmd, char_u *bufp, size_t bufsize, long Prenum);
13 static void win_init(win_T *newp, win_T *oldp, int flags);
14 static void win_init_some(win_T *newp, win_T *oldp);
15 static void frame_comp_pos(frame_T *topfrp, int *row, int *col);
16 static void frame_setheight(frame_T *curfrp, int height);
17 static void frame_setwidth(frame_T *curfrp, int width);
18 static void win_exchange(long);
19 static void win_rotate(int, int);
20 static void win_totop(int size, int flags);
21 static void win_equal_rec(win_T *next_curwin, int current, frame_T *topfr, int dir, int col, int row, int width, int height);
22 static win_T *win_free_mem(win_T *win, int *dirp, tabpage_T *tp);
23 static frame_T *win_altframe(win_T *win, tabpage_T *tp);
24 static tabpage_T *alt_tabpage(void);
25 static win_T *frame2win(frame_T *frp);
26 static int frame_has_win(frame_T *frp, win_T *wp);
27 static void frame_new_height(frame_T *topfrp, int height, int topfirst, int wfh);
28 static int frame_fixed_height(frame_T *frp);
29 static int frame_fixed_width(frame_T *frp);
30 static void frame_add_statusline(frame_T *frp);
31 static void frame_new_width(frame_T *topfrp, int width, int leftfirst, int wfw);
32 static void frame_add_vsep(frame_T *frp);
33 static int frame_minwidth(frame_T *topfrp, win_T *next_curwin);
34 static void frame_fix_width(win_T *wp);
35 static int win_alloc_firstwin(win_T *oldwin);
36 static void new_frame(win_T *wp);
37 static tabpage_T *alloc_tabpage(void);
38 static int leave_tabpage(buf_T *new_curbuf, int trigger_leave_autocmds);
39 static void enter_tabpage(tabpage_T *tp, buf_T *old_curbuf, int trigger_enter_autocmds, int trigger_leave_autocmds);
40 static void frame_fix_height(win_T *wp);
41 static int frame_minheight(frame_T *topfrp, win_T *next_curwin);
42 static int may_open_tabpage(void);
43 static void win_enter_ext(win_T *wp, int undo_sync, int no_curwin, int trigger_new_autocmds, int trigger_enter_autocmds, int trigger_leave_autocmds);
44 static void win_free(win_T *wp, tabpage_T *tp);
45 static int win_unlisted(win_T *wp);
46 static void win_append(win_T *after, win_T *wp);
47 static void frame_append(frame_T *after, frame_T *frp);
48 static void frame_insert(frame_T *before, frame_T *frp);
49 static void frame_remove(frame_T *frp);
50 static void win_goto_ver(int up, long count);
51 static void win_goto_hor(int left, long count);
52 static void frame_add_height(frame_T *frp, int n);
53 static void last_status_rec(frame_T *fr, int statusline);
54 
55 static void make_snapshot_rec(frame_T *fr, frame_T **frp);
56 static void clear_snapshot(tabpage_T *tp, int idx);
57 static void clear_snapshot_rec(frame_T *fr);
58 static int check_snapshot_rec(frame_T *sn, frame_T *fr);
59 static win_T *restore_snapshot_rec(frame_T *sn, frame_T *fr);
60 
61 static int frame_check_height(frame_T *topfrp, int height);
62 static int frame_check_width(frame_T *topfrp, int width);
63 
64 static win_T *win_alloc(win_T *after, int hidden);
65 
66 #define NOWIN		(win_T *)-1	// non-existing window
67 
68 #define ROWS_AVAIL (Rows - p_ch - tabline_height())
69 
70 static char *m_onlyone = N_("Already only one window");
71 
72 // When non-zero splitting a window is forbidden.  Used to avoid that nasty
73 // autocommands mess up the window structure.
74 static int split_disallowed = 0;
75 
76 // #define WIN_DEBUG
77 #ifdef WIN_DEBUG
78 /*
79  * Call this method to log the current window layout.
80  */
81     static void
82 log_frame_layout(frame_T *frame)
83 {
84     ch_log(NULL, "layout %s, wi: %d, he: %d, wwi: %d, whe: %d, id: %d",
85 	    frame->fr_layout == FR_LEAF ? "LEAF"
86 				  : frame->fr_layout == FR_ROW ? "ROW" : "COL",
87 	    frame->fr_width,
88 	    frame->fr_height,
89 	    frame->fr_win == NULL ? -1 : frame->fr_win->w_width,
90 	    frame->fr_win == NULL ? -1 : frame->fr_win->w_height,
91 	    frame->fr_win == NULL ? -1 : frame->fr_win->w_id);
92     if (frame->fr_child != NULL)
93     {
94 	ch_log(NULL, "children");
95 	log_frame_layout(frame->fr_child);
96 	if (frame->fr_next != NULL)
97 	    ch_log(NULL, "END of children");
98     }
99     if (frame->fr_next != NULL)
100 	log_frame_layout(frame->fr_next);
101 }
102 #endif
103 
104 /*
105  * All CTRL-W window commands are handled here, called from normal_cmd().
106  */
107     void
108 do_window(
109     int		nchar,
110     long	Prenum,
111     int		xchar)	    // extra char from ":wincmd gx" or NUL
112 {
113     long	Prenum1;
114     win_T	*wp;
115 #if defined(FEAT_SEARCHPATH) || defined(FEAT_FIND_ID)
116     char_u	*ptr;
117     linenr_T    lnum = -1;
118 #endif
119 #ifdef FEAT_FIND_ID
120     int		type = FIND_DEFINE;
121     int		len;
122 #endif
123     char_u	cbuf[40];
124 
125     if (ERROR_IF_ANY_POPUP_WINDOW)
126 	return;
127 
128 #ifdef FEAT_CMDWIN
129 # define CHECK_CMDWIN \
130     do { \
131 	if (cmdwin_type != 0) \
132 	{ \
133 	    emsg(_(e_cmdwin)); \
134 	    return; \
135 	} \
136     } while (0)
137 #else
138 # define CHECK_CMDWIN do { /**/ } while (0)
139 #endif
140 
141     Prenum1 = Prenum == 0 ? 1 : Prenum;
142 
143     switch (nchar)
144     {
145 // split current window in two parts, horizontally
146     case 'S':
147     case Ctrl_S:
148     case 's':
149 		CHECK_CMDWIN;
150 		reset_VIsual_and_resel();	// stop Visual mode
151 #ifdef FEAT_QUICKFIX
152 		// When splitting the quickfix window open a new buffer in it,
153 		// don't replicate the quickfix buffer.
154 		if (bt_quickfix(curbuf))
155 		    goto newwindow;
156 #endif
157 #ifdef FEAT_GUI
158 		need_mouse_correct = TRUE;
159 #endif
160 		(void)win_split((int)Prenum, 0);
161 		break;
162 
163 // split current window in two parts, vertically
164     case Ctrl_V:
165     case 'v':
166 		CHECK_CMDWIN;
167 		reset_VIsual_and_resel();	// stop Visual mode
168 #ifdef FEAT_QUICKFIX
169 		// When splitting the quickfix window open a new buffer in it,
170 		// don't replicate the quickfix buffer.
171 		if (bt_quickfix(curbuf))
172 		    goto newwindow;
173 #endif
174 #ifdef FEAT_GUI
175 		need_mouse_correct = TRUE;
176 #endif
177 		(void)win_split((int)Prenum, WSP_VERT);
178 		break;
179 
180 // split current window and edit alternate file
181     case Ctrl_HAT:
182     case '^':
183 		CHECK_CMDWIN;
184 		reset_VIsual_and_resel();	// stop Visual mode
185 
186 		if (buflist_findnr(Prenum == 0
187 					? curwin->w_alt_fnum : Prenum) == NULL)
188 		{
189 		    if (Prenum == 0)
190 			emsg(_(e_noalt));
191 		    else
192 			semsg(_("E92: Buffer %ld not found"), Prenum);
193 		    break;
194 		}
195 
196 		if (!curbuf_locked() && win_split(0, 0) == OK)
197 		    (void)buflist_getfile(
198 			    Prenum == 0 ? curwin->w_alt_fnum : Prenum,
199 			    (linenr_T)0, GETF_ALT, FALSE);
200 		break;
201 
202 // open new window
203     case Ctrl_N:
204     case 'n':
205 		CHECK_CMDWIN;
206 		reset_VIsual_and_resel();	// stop Visual mode
207 #ifdef FEAT_QUICKFIX
208 newwindow:
209 #endif
210 		if (Prenum)
211 		    // window height
212 		    vim_snprintf((char *)cbuf, sizeof(cbuf) - 5, "%ld", Prenum);
213 		else
214 		    cbuf[0] = NUL;
215 #if defined(FEAT_QUICKFIX)
216 		if (nchar == 'v' || nchar == Ctrl_V)
217 		    STRCAT(cbuf, "v");
218 #endif
219 		STRCAT(cbuf, "new");
220 		do_cmdline_cmd(cbuf);
221 		break;
222 
223 // quit current window
224     case Ctrl_Q:
225     case 'q':
226 		reset_VIsual_and_resel();	// stop Visual mode
227 		cmd_with_count("quit", cbuf, sizeof(cbuf), Prenum);
228 		do_cmdline_cmd(cbuf);
229 		break;
230 
231 // close current window
232     case Ctrl_C:
233     case 'c':
234 		reset_VIsual_and_resel();	// stop Visual mode
235 		cmd_with_count("close", cbuf, sizeof(cbuf), Prenum);
236 		do_cmdline_cmd(cbuf);
237 		break;
238 
239 #if defined(FEAT_QUICKFIX)
240 // close preview window
241     case Ctrl_Z:
242     case 'z':
243 		CHECK_CMDWIN;
244 		reset_VIsual_and_resel();	// stop Visual mode
245 		do_cmdline_cmd((char_u *)"pclose");
246 		break;
247 
248 // cursor to preview window
249     case 'P':
250 		FOR_ALL_WINDOWS(wp)
251 		    if (wp->w_p_pvw)
252 			break;
253 		if (wp == NULL)
254 		    emsg(_("E441: There is no preview window"));
255 		else
256 		    win_goto(wp);
257 		break;
258 #endif
259 
260 // close all but current window
261     case Ctrl_O:
262     case 'o':
263 		CHECK_CMDWIN;
264 		reset_VIsual_and_resel();	// stop Visual mode
265 		cmd_with_count("only", cbuf, sizeof(cbuf), Prenum);
266 		do_cmdline_cmd(cbuf);
267 		break;
268 
269 // cursor to next window with wrap around
270     case Ctrl_W:
271     case 'w':
272 // cursor to previous window with wrap around
273     case 'W':
274 		CHECK_CMDWIN;
275 		if (ONE_WINDOW && Prenum != 1)	// just one window
276 		    beep_flush();
277 		else
278 		{
279 		    if (Prenum)			// go to specified window
280 		    {
281 			for (wp = firstwin; --Prenum > 0; )
282 			{
283 			    if (wp->w_next == NULL)
284 				break;
285 			    else
286 				wp = wp->w_next;
287 			}
288 		    }
289 		    else
290 		    {
291 			if (nchar == 'W')	    // go to previous window
292 			{
293 			    wp = curwin->w_prev;
294 			    if (wp == NULL)
295 				wp = lastwin;	    // wrap around
296 			}
297 			else			    // go to next window
298 			{
299 			    wp = curwin->w_next;
300 			    if (wp == NULL)
301 				wp = firstwin;	    // wrap around
302 			}
303 		    }
304 		    win_goto(wp);
305 		}
306 		break;
307 
308 // cursor to window below
309     case 'j':
310     case K_DOWN:
311     case Ctrl_J:
312 		CHECK_CMDWIN;
313 		win_goto_ver(FALSE, Prenum1);
314 		break;
315 
316 // cursor to window above
317     case 'k':
318     case K_UP:
319     case Ctrl_K:
320 		CHECK_CMDWIN;
321 		win_goto_ver(TRUE, Prenum1);
322 		break;
323 
324 // cursor to left window
325     case 'h':
326     case K_LEFT:
327     case Ctrl_H:
328     case K_BS:
329 		CHECK_CMDWIN;
330 		win_goto_hor(TRUE, Prenum1);
331 		break;
332 
333 // cursor to right window
334     case 'l':
335     case K_RIGHT:
336     case Ctrl_L:
337 		CHECK_CMDWIN;
338 		win_goto_hor(FALSE, Prenum1);
339 		break;
340 
341 // move window to new tab page
342     case 'T':
343 		CHECK_CMDWIN;
344 		if (one_window())
345 		    msg(_(m_onlyone));
346 		else
347 		{
348 		    tabpage_T	*oldtab = curtab;
349 		    tabpage_T	*newtab;
350 
351 		    // First create a new tab with the window, then go back to
352 		    // the old tab and close the window there.
353 		    wp = curwin;
354 		    if (win_new_tabpage((int)Prenum) == OK
355 						     && valid_tabpage(oldtab))
356 		    {
357 			newtab = curtab;
358 			goto_tabpage_tp(oldtab, TRUE, TRUE);
359 			if (curwin == wp)
360 			    win_close(curwin, FALSE);
361 			if (valid_tabpage(newtab))
362 			    goto_tabpage_tp(newtab, TRUE, TRUE);
363 		    }
364 		}
365 		break;
366 
367 // cursor to top-left window
368     case 't':
369     case Ctrl_T:
370 		win_goto(firstwin);
371 		break;
372 
373 // cursor to bottom-right window
374     case 'b':
375     case Ctrl_B:
376 		win_goto(lastwin);
377 		break;
378 
379 // cursor to last accessed (previous) window
380     case 'p':
381     case Ctrl_P:
382 		if (!win_valid(prevwin))
383 		    beep_flush();
384 		else
385 		    win_goto(prevwin);
386 		break;
387 
388 // exchange current and next window
389     case 'x':
390     case Ctrl_X:
391 		CHECK_CMDWIN;
392 		win_exchange(Prenum);
393 		break;
394 
395 // rotate windows downwards
396     case Ctrl_R:
397     case 'r':
398 		CHECK_CMDWIN;
399 		reset_VIsual_and_resel();	// stop Visual mode
400 		win_rotate(FALSE, (int)Prenum1);    // downwards
401 		break;
402 
403 // rotate windows upwards
404     case 'R':
405 		CHECK_CMDWIN;
406 		reset_VIsual_and_resel();	// stop Visual mode
407 		win_rotate(TRUE, (int)Prenum1);	    // upwards
408 		break;
409 
410 // move window to the very top/bottom/left/right
411     case 'K':
412     case 'J':
413     case 'H':
414     case 'L':
415 		CHECK_CMDWIN;
416 		win_totop((int)Prenum,
417 			((nchar == 'H' || nchar == 'L') ? WSP_VERT : 0)
418 			| ((nchar == 'H' || nchar == 'K') ? WSP_TOP : WSP_BOT));
419 		break;
420 
421 // make all windows the same height
422     case '=':
423 #ifdef FEAT_GUI
424 		need_mouse_correct = TRUE;
425 #endif
426 		win_equal(NULL, FALSE, 'b');
427 		break;
428 
429 // increase current window height
430     case '+':
431 #ifdef FEAT_GUI
432 		need_mouse_correct = TRUE;
433 #endif
434 		win_setheight(curwin->w_height + (int)Prenum1);
435 		break;
436 
437 // decrease current window height
438     case '-':
439 #ifdef FEAT_GUI
440 		need_mouse_correct = TRUE;
441 #endif
442 		win_setheight(curwin->w_height - (int)Prenum1);
443 		break;
444 
445 // set current window height
446     case Ctrl__:
447     case '_':
448 #ifdef FEAT_GUI
449 		need_mouse_correct = TRUE;
450 #endif
451 		win_setheight(Prenum ? (int)Prenum : 9999);
452 		break;
453 
454 // increase current window width
455     case '>':
456 #ifdef FEAT_GUI
457 		need_mouse_correct = TRUE;
458 #endif
459 		win_setwidth(curwin->w_width + (int)Prenum1);
460 		break;
461 
462 // decrease current window width
463     case '<':
464 #ifdef FEAT_GUI
465 		need_mouse_correct = TRUE;
466 #endif
467 		win_setwidth(curwin->w_width - (int)Prenum1);
468 		break;
469 
470 // set current window width
471     case '|':
472 #ifdef FEAT_GUI
473 		need_mouse_correct = TRUE;
474 #endif
475 		win_setwidth(Prenum != 0 ? (int)Prenum : 9999);
476 		break;
477 
478 // jump to tag and split window if tag exists (in preview window)
479 #if defined(FEAT_QUICKFIX)
480     case '}':
481 		CHECK_CMDWIN;
482 		if (Prenum)
483 		    g_do_tagpreview = Prenum;
484 		else
485 		    g_do_tagpreview = p_pvh;
486 #endif
487 		// FALLTHROUGH
488     case ']':
489     case Ctrl_RSB:
490 		CHECK_CMDWIN;
491 		// keep Visual mode, can select words to use as a tag
492 		if (Prenum)
493 		    postponed_split = Prenum;
494 		else
495 		    postponed_split = -1;
496 #ifdef FEAT_QUICKFIX
497 		if (nchar != '}')
498 		    g_do_tagpreview = 0;
499 #endif
500 
501 		// Execute the command right here, required when "wincmd ]"
502 		// was used in a function.
503 		do_nv_ident(Ctrl_RSB, NUL);
504 		break;
505 
506 #ifdef FEAT_SEARCHPATH
507 // edit file name under cursor in a new window
508     case 'f':
509     case 'F':
510     case Ctrl_F:
511 wingotofile:
512 		CHECK_CMDWIN;
513 
514 		ptr = grab_file_name(Prenum1, &lnum);
515 		if (ptr != NULL)
516 		{
517 		    tabpage_T	*oldtab = curtab;
518 		    win_T	*oldwin = curwin;
519 # ifdef FEAT_GUI
520 		    need_mouse_correct = TRUE;
521 # endif
522 		    setpcmark();
523 		    if (win_split(0, 0) == OK)
524 		    {
525 			RESET_BINDING(curwin);
526 			if (do_ecmd(0, ptr, NULL, NULL, ECMD_LASTL,
527 						   ECMD_HIDE, NULL) == FAIL)
528 			{
529 			    // Failed to open the file, close the window
530 			    // opened for it.
531 			    win_close(curwin, FALSE);
532 			    goto_tabpage_win(oldtab, oldwin);
533 			}
534 			else if (nchar == 'F' && lnum >= 0)
535 			{
536 			    curwin->w_cursor.lnum = lnum;
537 			    check_cursor_lnum();
538 			    beginline(BL_SOL | BL_FIX);
539 			}
540 		    }
541 		    vim_free(ptr);
542 		}
543 		break;
544 #endif
545 
546 #ifdef FEAT_FIND_ID
547 // Go to the first occurrence of the identifier under cursor along path in a
548 // new window -- webb
549     case 'i':			    // Go to any match
550     case Ctrl_I:
551 		type = FIND_ANY;
552 		// FALLTHROUGH
553     case 'd':			    // Go to definition, using 'define'
554     case Ctrl_D:
555 		CHECK_CMDWIN;
556 		if ((len = find_ident_under_cursor(&ptr, FIND_IDENT)) == 0)
557 		    break;
558 		find_pattern_in_path(ptr, 0, len, TRUE,
559 			Prenum == 0 ? TRUE : FALSE, type,
560 			Prenum1, ACTION_SPLIT, (linenr_T)1, (linenr_T)MAXLNUM);
561 		curwin->w_set_curswant = TRUE;
562 		break;
563 #endif
564 
565 // Quickfix window only: view the result under the cursor in a new split.
566 #if defined(FEAT_QUICKFIX)
567     case K_KENTER:
568     case CAR:
569 		if (bt_quickfix(curbuf))
570 		    qf_view_result(TRUE);
571 		break;
572 #endif
573 
574 // CTRL-W g  extended commands
575     case 'g':
576     case Ctrl_G:
577 		CHECK_CMDWIN;
578 #ifdef USE_ON_FLY_SCROLL
579 		dont_scroll = TRUE;		// disallow scrolling here
580 #endif
581 		++no_mapping;
582 		++allow_keys;   // no mapping for xchar, but allow key codes
583 		if (xchar == NUL)
584 		    xchar = plain_vgetc();
585 		LANGMAP_ADJUST(xchar, TRUE);
586 		--no_mapping;
587 		--allow_keys;
588 #ifdef FEAT_CMDL_INFO
589 		(void)add_to_showcmd(xchar);
590 #endif
591 		switch (xchar)
592 		{
593 #if defined(FEAT_QUICKFIX)
594 		    case '}':
595 			xchar = Ctrl_RSB;
596 			if (Prenum)
597 			    g_do_tagpreview = Prenum;
598 			else
599 			    g_do_tagpreview = p_pvh;
600 #endif
601 			// FALLTHROUGH
602 		    case ']':
603 		    case Ctrl_RSB:
604 			// keep Visual mode, can select words to use as a tag
605 			if (Prenum)
606 			    postponed_split = Prenum;
607 			else
608 			    postponed_split = -1;
609 
610 			// Execute the command right here, required when
611 			// "wincmd g}" was used in a function.
612 			do_nv_ident('g', xchar);
613 			break;
614 
615 #ifdef FEAT_SEARCHPATH
616 		    case 'f':	    // CTRL-W gf: "gf" in a new tab page
617 		    case 'F':	    // CTRL-W gF: "gF" in a new tab page
618 			cmdmod.tab = tabpage_index(curtab) + 1;
619 			nchar = xchar;
620 			goto wingotofile;
621 #endif
622 		    case 't':	    // CTRL-W gt: go to next tab page
623 			goto_tabpage((int)Prenum);
624 			break;
625 
626 		    case 'T':	    // CTRL-W gT: go to previous tab page
627 			goto_tabpage(-(int)Prenum1);
628 			break;
629 
630 		    default:
631 			beep_flush();
632 			break;
633 		}
634 		break;
635 
636     default:	beep_flush();
637 		break;
638     }
639 }
640 
641 /*
642  * Figure out the address type for ":wincmd".
643  */
644     void
645 get_wincmd_addr_type(char_u *arg, exarg_T *eap)
646 {
647     switch (*arg)
648     {
649     case 'S':
650     case Ctrl_S:
651     case 's':
652     case Ctrl_N:
653     case 'n':
654     case 'j':
655     case Ctrl_J:
656     case 'k':
657     case Ctrl_K:
658     case 'T':
659     case Ctrl_R:
660     case 'r':
661     case 'R':
662     case 'K':
663     case 'J':
664     case '+':
665     case '-':
666     case Ctrl__:
667     case '_':
668     case '|':
669     case ']':
670     case Ctrl_RSB:
671     case 'g':
672     case Ctrl_G:
673     case Ctrl_V:
674     case 'v':
675     case 'h':
676     case Ctrl_H:
677     case 'l':
678     case Ctrl_L:
679     case 'H':
680     case 'L':
681     case '>':
682     case '<':
683 #if defined(FEAT_QUICKFIX)
684     case '}':
685 #endif
686 #ifdef FEAT_SEARCHPATH
687     case 'f':
688     case 'F':
689     case Ctrl_F:
690 #endif
691 #ifdef FEAT_FIND_ID
692     case 'i':
693     case Ctrl_I:
694     case 'd':
695     case Ctrl_D:
696 #endif
697 		// window size or any count
698 		eap->addr_type = ADDR_OTHER;
699 		break;
700 
701     case Ctrl_HAT:
702     case '^':
703 		// buffer number
704 		eap->addr_type = ADDR_BUFFERS;
705 		break;
706 
707     case Ctrl_Q:
708     case 'q':
709     case Ctrl_C:
710     case 'c':
711     case Ctrl_O:
712     case 'o':
713     case Ctrl_W:
714     case 'w':
715     case 'W':
716     case 'x':
717     case Ctrl_X:
718 		// window number
719 		eap->addr_type = ADDR_WINDOWS;
720 		break;
721 
722 #if defined(FEAT_QUICKFIX)
723     case Ctrl_Z:
724     case 'z':
725     case 'P':
726 #endif
727     case 't':
728     case Ctrl_T:
729     case 'b':
730     case Ctrl_B:
731     case 'p':
732     case Ctrl_P:
733     case '=':
734     case CAR:
735 		// no count
736 		eap->addr_type = ADDR_NONE;
737 		break;
738     }
739 }
740 
741     static void
742 cmd_with_count(
743     char	*cmd,
744     char_u	*bufp,
745     size_t	bufsize,
746     long	Prenum)
747 {
748     size_t	len = STRLEN(cmd);
749 
750     STRCPY(bufp, cmd);
751     if (Prenum > 0)
752 	vim_snprintf((char *)bufp + len, bufsize - len, "%ld", Prenum);
753 }
754 
755 /*
756  * If "split_disallowed" is set given an error and return FAIL.
757  * Otherwise return OK.
758  */
759     static int
760 check_split_disallowed()
761 {
762     if (split_disallowed > 0)
763     {
764 	emsg(_("E242: Can't split a window while closing another"));
765 	return FAIL;
766     }
767     return OK;
768 }
769 
770 /*
771  * split the current window, implements CTRL-W s and :split
772  *
773  * "size" is the height or width for the new window, 0 to use half of current
774  * height or width.
775  *
776  * "flags":
777  * WSP_ROOM: require enough room for new window
778  * WSP_VERT: vertical split.
779  * WSP_TOP:  open window at the top-left of the shell (help window).
780  * WSP_BOT:  open window at the bottom-right of the shell (quickfix window).
781  * WSP_HELP: creating the help window, keep layout snapshot
782  *
783  * return FAIL for failure, OK otherwise
784  */
785     int
786 win_split(int size, int flags)
787 {
788     if (ERROR_IF_ANY_POPUP_WINDOW)
789 	return FAIL;
790 
791     // When the ":tab" modifier was used open a new tab page instead.
792     if (may_open_tabpage() == OK)
793 	return OK;
794 
795     // Add flags from ":vertical", ":topleft" and ":botright".
796     flags |= cmdmod.split;
797     if ((flags & WSP_TOP) && (flags & WSP_BOT))
798     {
799 	emsg(_("E442: Can't split topleft and botright at the same time"));
800 	return FAIL;
801     }
802     if (check_split_disallowed() == FAIL)
803 	return FAIL;
804 
805     // When creating the help window make a snapshot of the window layout.
806     // Otherwise clear the snapshot, it's now invalid.
807     if (flags & WSP_HELP)
808 	make_snapshot(SNAP_HELP_IDX);
809     else
810 	clear_snapshot(curtab, SNAP_HELP_IDX);
811 
812     return win_split_ins(size, flags, NULL, 0);
813 }
814 
815 /*
816  * When "new_wp" is NULL: split the current window in two.
817  * When "new_wp" is not NULL: insert this window at the far
818  * top/left/right/bottom.
819  * return FAIL for failure, OK otherwise
820  */
821     int
822 win_split_ins(
823     int		size,
824     int		flags,
825     win_T	*new_wp,
826     int		dir)
827 {
828     win_T	*wp = new_wp;
829     win_T	*oldwin;
830     int		new_size = size;
831     int		i;
832     int		need_status = 0;
833     int		do_equal = FALSE;
834     int		needed;
835     int		available;
836     int		oldwin_height = 0;
837     int		layout;
838     frame_T	*frp, *curfrp, *frp2, *prevfrp;
839     int		before;
840     int		minheight;
841     int		wmh1;
842     int		did_set_fraction = FALSE;
843 
844     if (flags & WSP_TOP)
845 	oldwin = firstwin;
846     else if (flags & WSP_BOT)
847 	oldwin = lastwin;
848     else
849 	oldwin = curwin;
850 
851     // add a status line when p_ls == 1 and splitting the first window
852     if (ONE_WINDOW && p_ls == 1 && oldwin->w_status_height == 0)
853     {
854 	if (VISIBLE_HEIGHT(oldwin) <= p_wmh && new_wp == NULL)
855 	{
856 	    emsg(_(e_noroom));
857 	    return FAIL;
858 	}
859 	need_status = STATUS_HEIGHT;
860     }
861 
862 #ifdef FEAT_GUI
863     // May be needed for the scrollbars that are going to change.
864     if (gui.in_use)
865 	out_flush();
866 #endif
867 
868     if (flags & WSP_VERT)
869     {
870 	int	wmw1;
871 	int	minwidth;
872 
873 	layout = FR_ROW;
874 
875 	/*
876 	 * Check if we are able to split the current window and compute its
877 	 * width.
878 	 */
879 	// Current window requires at least 1 space.
880 	wmw1 = (p_wmw == 0 ? 1 : p_wmw);
881 	needed = wmw1 + 1;
882 	if (flags & WSP_ROOM)
883 	    needed += p_wiw - wmw1;
884 	if (flags & (WSP_BOT | WSP_TOP))
885 	{
886 	    minwidth = frame_minwidth(topframe, NOWIN);
887 	    available = topframe->fr_width;
888 	    needed += minwidth;
889 	}
890 	else if (p_ea)
891 	{
892 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
893 	    prevfrp = oldwin->w_frame;
894 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
895 							frp = frp->fr_parent)
896 	    {
897 		if (frp->fr_layout == FR_ROW)
898 		    FOR_ALL_FRAMES(frp2, frp->fr_child)
899 			if (frp2 != prevfrp)
900 			    minwidth += frame_minwidth(frp2, NOWIN);
901 		prevfrp = frp;
902 	    }
903 	    available = topframe->fr_width;
904 	    needed += minwidth;
905 	}
906 	else
907 	{
908 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
909 	    available = oldwin->w_frame->fr_width;
910 	    needed += minwidth;
911 	}
912 	if (available < needed && new_wp == NULL)
913 	{
914 	    emsg(_(e_noroom));
915 	    return FAIL;
916 	}
917 	if (new_size == 0)
918 	    new_size = oldwin->w_width / 2;
919 	if (new_size > available - minwidth - 1)
920 	    new_size = available - minwidth - 1;
921 	if (new_size < wmw1)
922 	    new_size = wmw1;
923 
924 	// if it doesn't fit in the current window, need win_equal()
925 	if (oldwin->w_width - new_size - 1 < p_wmw)
926 	    do_equal = TRUE;
927 
928 	// We don't like to take lines for the new window from a
929 	// 'winfixwidth' window.  Take them from a window to the left or right
930 	// instead, if possible. Add one for the separator.
931 	if (oldwin->w_p_wfw)
932 	    win_setwidth_win(oldwin->w_width + new_size + 1, oldwin);
933 
934 	// Only make all windows the same width if one of them (except oldwin)
935 	// is wider than one of the split windows.
936 	if (!do_equal && p_ea && size == 0 && *p_ead != 'v'
937 					 && oldwin->w_frame->fr_parent != NULL)
938 	{
939 	    frp = oldwin->w_frame->fr_parent->fr_child;
940 	    while (frp != NULL)
941 	    {
942 		if (frp->fr_win != oldwin && frp->fr_win != NULL
943 			&& (frp->fr_win->w_width > new_size
944 			    || frp->fr_win->w_width > oldwin->w_width
945 							      - new_size - 1))
946 		{
947 		    do_equal = TRUE;
948 		    break;
949 		}
950 		frp = frp->fr_next;
951 	    }
952 	}
953     }
954     else
955     {
956 	layout = FR_COL;
957 
958 	/*
959 	 * Check if we are able to split the current window and compute its
960 	 * height.
961 	 */
962 	// Current window requires at least 1 space.
963 	wmh1 = (p_wmh == 0 ? 1 : p_wmh) + WINBAR_HEIGHT(curwin);
964 	needed = wmh1 + STATUS_HEIGHT;
965 	if (flags & WSP_ROOM)
966 	    needed += p_wh - wmh1;
967 	if (flags & (WSP_BOT | WSP_TOP))
968 	{
969 	    minheight = frame_minheight(topframe, NOWIN) + need_status;
970 	    available = topframe->fr_height;
971 	    needed += minheight;
972 	}
973 	else if (p_ea)
974 	{
975 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
976 	    prevfrp = oldwin->w_frame;
977 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
978 							frp = frp->fr_parent)
979 	    {
980 		if (frp->fr_layout == FR_COL)
981 		    FOR_ALL_FRAMES(frp2, frp->fr_child)
982 			if (frp2 != prevfrp)
983 			    minheight += frame_minheight(frp2, NOWIN);
984 		prevfrp = frp;
985 	    }
986 	    available = topframe->fr_height;
987 	    needed += minheight;
988 	}
989 	else
990 	{
991 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
992 	    available = oldwin->w_frame->fr_height;
993 	    needed += minheight;
994 	}
995 	if (available < needed && new_wp == NULL)
996 	{
997 	    emsg(_(e_noroom));
998 	    return FAIL;
999 	}
1000 	oldwin_height = oldwin->w_height;
1001 	if (need_status)
1002 	{
1003 	    oldwin->w_status_height = STATUS_HEIGHT;
1004 	    oldwin_height -= STATUS_HEIGHT;
1005 	}
1006 	if (new_size == 0)
1007 	    new_size = oldwin_height / 2;
1008 	if (new_size > available - minheight - STATUS_HEIGHT)
1009 	    new_size = available - minheight - STATUS_HEIGHT;
1010 	if (new_size < wmh1)
1011 	    new_size = wmh1;
1012 
1013 	// if it doesn't fit in the current window, need win_equal()
1014 	if (oldwin_height - new_size - STATUS_HEIGHT < p_wmh)
1015 	    do_equal = TRUE;
1016 
1017 	// We don't like to take lines for the new window from a
1018 	// 'winfixheight' window.  Take them from a window above or below
1019 	// instead, if possible.
1020 	if (oldwin->w_p_wfh)
1021 	{
1022 	    // Set w_fraction now so that the cursor keeps the same relative
1023 	    // vertical position using the old height.
1024 	    set_fraction(oldwin);
1025 	    did_set_fraction = TRUE;
1026 
1027 	    win_setheight_win(oldwin->w_height + new_size + STATUS_HEIGHT,
1028 								      oldwin);
1029 	    oldwin_height = oldwin->w_height;
1030 	    if (need_status)
1031 		oldwin_height -= STATUS_HEIGHT;
1032 	}
1033 
1034 	// Only make all windows the same height if one of them (except oldwin)
1035 	// is higher than one of the split windows.
1036 	if (!do_equal && p_ea && size == 0 && *p_ead != 'h'
1037 	   && oldwin->w_frame->fr_parent != NULL)
1038 	{
1039 	    frp = oldwin->w_frame->fr_parent->fr_child;
1040 	    while (frp != NULL)
1041 	    {
1042 		if (frp->fr_win != oldwin && frp->fr_win != NULL
1043 			&& (frp->fr_win->w_height > new_size
1044 			    || frp->fr_win->w_height > oldwin_height - new_size
1045 							      - STATUS_HEIGHT))
1046 		{
1047 		    do_equal = TRUE;
1048 		    break;
1049 		}
1050 		frp = frp->fr_next;
1051 	    }
1052 	}
1053     }
1054 
1055     /*
1056      * allocate new window structure and link it in the window list
1057      */
1058     if ((flags & WSP_TOP) == 0
1059 	    && ((flags & WSP_BOT)
1060 		|| (flags & WSP_BELOW)
1061 		|| (!(flags & WSP_ABOVE)
1062 		    && ( (flags & WSP_VERT) ? p_spr : p_sb))))
1063     {
1064 	// new window below/right of current one
1065 	if (new_wp == NULL)
1066 	    wp = win_alloc(oldwin, FALSE);
1067 	else
1068 	    win_append(oldwin, wp);
1069     }
1070     else
1071     {
1072 	if (new_wp == NULL)
1073 	    wp = win_alloc(oldwin->w_prev, FALSE);
1074 	else
1075 	    win_append(oldwin->w_prev, wp);
1076     }
1077 
1078     if (new_wp == NULL)
1079     {
1080 	if (wp == NULL)
1081 	    return FAIL;
1082 
1083 	new_frame(wp);
1084 	if (wp->w_frame == NULL)
1085 	{
1086 	    win_free(wp, NULL);
1087 	    return FAIL;
1088 	}
1089 
1090 	// make the contents of the new window the same as the current one
1091 	win_init(wp, curwin, flags);
1092     }
1093 
1094     /*
1095      * Reorganise the tree of frames to insert the new window.
1096      */
1097     if (flags & (WSP_TOP | WSP_BOT))
1098     {
1099 	if ((topframe->fr_layout == FR_COL && (flags & WSP_VERT) == 0)
1100 	    || (topframe->fr_layout == FR_ROW && (flags & WSP_VERT) != 0))
1101 	{
1102 	    curfrp = topframe->fr_child;
1103 	    if (flags & WSP_BOT)
1104 		while (curfrp->fr_next != NULL)
1105 		    curfrp = curfrp->fr_next;
1106 	}
1107 	else
1108 	    curfrp = topframe;
1109 	before = (flags & WSP_TOP);
1110     }
1111     else
1112     {
1113 	curfrp = oldwin->w_frame;
1114 	if (flags & WSP_BELOW)
1115 	    before = FALSE;
1116 	else if (flags & WSP_ABOVE)
1117 	    before = TRUE;
1118 	else if (flags & WSP_VERT)
1119 	    before = !p_spr;
1120 	else
1121 	    before = !p_sb;
1122     }
1123     if (curfrp->fr_parent == NULL || curfrp->fr_parent->fr_layout != layout)
1124     {
1125 	// Need to create a new frame in the tree to make a branch.
1126 	frp = ALLOC_CLEAR_ONE(frame_T);
1127 	*frp = *curfrp;
1128 	curfrp->fr_layout = layout;
1129 	frp->fr_parent = curfrp;
1130 	frp->fr_next = NULL;
1131 	frp->fr_prev = NULL;
1132 	curfrp->fr_child = frp;
1133 	curfrp->fr_win = NULL;
1134 	curfrp = frp;
1135 	if (frp->fr_win != NULL)
1136 	    oldwin->w_frame = frp;
1137 	else
1138 	    FOR_ALL_FRAMES(frp, frp->fr_child)
1139 		frp->fr_parent = curfrp;
1140     }
1141 
1142     if (new_wp == NULL)
1143 	frp = wp->w_frame;
1144     else
1145 	frp = new_wp->w_frame;
1146     frp->fr_parent = curfrp->fr_parent;
1147 
1148     // Insert the new frame at the right place in the frame list.
1149     if (before)
1150 	frame_insert(curfrp, frp);
1151     else
1152 	frame_append(curfrp, frp);
1153 
1154     // Set w_fraction now so that the cursor keeps the same relative
1155     // vertical position.
1156     if (!did_set_fraction)
1157 	set_fraction(oldwin);
1158     wp->w_fraction = oldwin->w_fraction;
1159 
1160     if (flags & WSP_VERT)
1161     {
1162 	wp->w_p_scr = curwin->w_p_scr;
1163 
1164 	if (need_status)
1165 	{
1166 	    win_new_height(oldwin, oldwin->w_height - 1);
1167 	    oldwin->w_status_height = need_status;
1168 	}
1169 	if (flags & (WSP_TOP | WSP_BOT))
1170 	{
1171 	    // set height and row of new window to full height
1172 	    wp->w_winrow = tabline_height();
1173 	    win_new_height(wp, curfrp->fr_height - (p_ls > 0)
1174 							  - WINBAR_HEIGHT(wp));
1175 	    wp->w_status_height = (p_ls > 0);
1176 	}
1177 	else
1178 	{
1179 	    // height and row of new window is same as current window
1180 	    wp->w_winrow = oldwin->w_winrow;
1181 	    win_new_height(wp, VISIBLE_HEIGHT(oldwin));
1182 	    wp->w_status_height = oldwin->w_status_height;
1183 	}
1184 	frp->fr_height = curfrp->fr_height;
1185 
1186 	// "new_size" of the current window goes to the new window, use
1187 	// one column for the vertical separator
1188 	win_new_width(wp, new_size);
1189 	if (before)
1190 	    wp->w_vsep_width = 1;
1191 	else
1192 	{
1193 	    wp->w_vsep_width = oldwin->w_vsep_width;
1194 	    oldwin->w_vsep_width = 1;
1195 	}
1196 	if (flags & (WSP_TOP | WSP_BOT))
1197 	{
1198 	    if (flags & WSP_BOT)
1199 		frame_add_vsep(curfrp);
1200 	    // Set width of neighbor frame
1201 	    frame_new_width(curfrp, curfrp->fr_width
1202 		     - (new_size + ((flags & WSP_TOP) != 0)), flags & WSP_TOP,
1203 								       FALSE);
1204 	}
1205 	else
1206 	    win_new_width(oldwin, oldwin->w_width - (new_size + 1));
1207 	if (before)	// new window left of current one
1208 	{
1209 	    wp->w_wincol = oldwin->w_wincol;
1210 	    oldwin->w_wincol += new_size + 1;
1211 	}
1212 	else		// new window right of current one
1213 	    wp->w_wincol = oldwin->w_wincol + oldwin->w_width + 1;
1214 	frame_fix_width(oldwin);
1215 	frame_fix_width(wp);
1216     }
1217     else
1218     {
1219 	// width and column of new window is same as current window
1220 	if (flags & (WSP_TOP | WSP_BOT))
1221 	{
1222 	    wp->w_wincol = 0;
1223 	    win_new_width(wp, Columns);
1224 	    wp->w_vsep_width = 0;
1225 	}
1226 	else
1227 	{
1228 	    wp->w_wincol = oldwin->w_wincol;
1229 	    win_new_width(wp, oldwin->w_width);
1230 	    wp->w_vsep_width = oldwin->w_vsep_width;
1231 	}
1232 	frp->fr_width = curfrp->fr_width;
1233 
1234 	// "new_size" of the current window goes to the new window, use
1235 	// one row for the status line
1236 	win_new_height(wp, new_size);
1237 	if (flags & (WSP_TOP | WSP_BOT))
1238 	{
1239 	    int new_fr_height = curfrp->fr_height - new_size
1240 							  + WINBAR_HEIGHT(wp) ;
1241 
1242 	    if (!((flags & WSP_BOT) && p_ls == 0))
1243 		new_fr_height -= STATUS_HEIGHT;
1244 	    frame_new_height(curfrp, new_fr_height, flags & WSP_TOP, FALSE);
1245 	}
1246 	else
1247 	    win_new_height(oldwin, oldwin_height - (new_size + STATUS_HEIGHT));
1248 	if (before)	// new window above current one
1249 	{
1250 	    wp->w_winrow = oldwin->w_winrow;
1251 	    wp->w_status_height = STATUS_HEIGHT;
1252 	    oldwin->w_winrow += wp->w_height + STATUS_HEIGHT;
1253 	}
1254 	else		// new window below current one
1255 	{
1256 	    wp->w_winrow = oldwin->w_winrow + VISIBLE_HEIGHT(oldwin)
1257 							       + STATUS_HEIGHT;
1258 	    wp->w_status_height = oldwin->w_status_height;
1259 	    if (!(flags & WSP_BOT))
1260 		oldwin->w_status_height = STATUS_HEIGHT;
1261 	}
1262 	if (flags & WSP_BOT)
1263 	    frame_add_statusline(curfrp);
1264 	frame_fix_height(wp);
1265 	frame_fix_height(oldwin);
1266     }
1267 
1268     if (flags & (WSP_TOP | WSP_BOT))
1269 	(void)win_comp_pos();
1270 
1271     /*
1272      * Both windows need redrawing
1273      */
1274     redraw_win_later(wp, NOT_VALID);
1275     wp->w_redr_status = TRUE;
1276     redraw_win_later(oldwin, NOT_VALID);
1277     oldwin->w_redr_status = TRUE;
1278 
1279     if (need_status)
1280     {
1281 	msg_row = Rows - 1;
1282 	msg_col = sc_col;
1283 	msg_clr_eos_force();	// Old command/ruler may still be there
1284 	comp_col();
1285 	msg_row = Rows - 1;
1286 	msg_col = 0;	// put position back at start of line
1287     }
1288 
1289     /*
1290      * equalize the window sizes.
1291      */
1292     if (do_equal || dir != 0)
1293 	win_equal(wp, TRUE,
1294 		(flags & WSP_VERT) ? (dir == 'v' ? 'b' : 'h')
1295 		: dir == 'h' ? 'b' : 'v');
1296 
1297     // Don't change the window height/width to 'winheight' / 'winwidth' if a
1298     // size was given.
1299     if (flags & WSP_VERT)
1300     {
1301 	i = p_wiw;
1302 	if (size != 0)
1303 	    p_wiw = size;
1304 
1305 # ifdef FEAT_GUI
1306 	// When 'guioptions' includes 'L' or 'R' may have to add scrollbars.
1307 	if (gui.in_use)
1308 	    gui_init_which_components(NULL);
1309 # endif
1310     }
1311     else
1312     {
1313 	i = p_wh;
1314 	if (size != 0)
1315 	    p_wh = size;
1316     }
1317 
1318 #ifdef FEAT_JUMPLIST
1319     // Keep same changelist position in new window.
1320     wp->w_changelistidx = oldwin->w_changelistidx;
1321 #endif
1322 
1323     /*
1324      * make the new window the current window
1325      */
1326     win_enter_ext(wp, FALSE, FALSE, TRUE, TRUE, TRUE);
1327     if (flags & WSP_VERT)
1328 	p_wiw = i;
1329     else
1330 	p_wh = i;
1331 
1332     return OK;
1333 }
1334 
1335 
1336 /*
1337  * Initialize window "newp" from window "oldp".
1338  * Used when splitting a window and when creating a new tab page.
1339  * The windows will both edit the same buffer.
1340  * WSP_NEWLOC may be specified in flags to prevent the location list from
1341  * being copied.
1342  */
1343     static void
1344 win_init(win_T *newp, win_T *oldp, int flags UNUSED)
1345 {
1346     int		i;
1347 
1348     newp->w_buffer = oldp->w_buffer;
1349 #ifdef FEAT_SYN_HL
1350     newp->w_s = &(oldp->w_buffer->b_s);
1351 #endif
1352     oldp->w_buffer->b_nwindows++;
1353     newp->w_cursor = oldp->w_cursor;
1354     newp->w_valid = 0;
1355     newp->w_curswant = oldp->w_curswant;
1356     newp->w_set_curswant = oldp->w_set_curswant;
1357     newp->w_topline = oldp->w_topline;
1358 #ifdef FEAT_DIFF
1359     newp->w_topfill = oldp->w_topfill;
1360 #endif
1361     newp->w_leftcol = oldp->w_leftcol;
1362     newp->w_pcmark = oldp->w_pcmark;
1363     newp->w_prev_pcmark = oldp->w_prev_pcmark;
1364     newp->w_alt_fnum = oldp->w_alt_fnum;
1365     newp->w_wrow = oldp->w_wrow;
1366     newp->w_fraction = oldp->w_fraction;
1367     newp->w_prev_fraction_row = oldp->w_prev_fraction_row;
1368 #ifdef FEAT_JUMPLIST
1369     copy_jumplist(oldp, newp);
1370 #endif
1371 #ifdef FEAT_QUICKFIX
1372     if (flags & WSP_NEWLOC)
1373     {
1374 	// Don't copy the location list.
1375 	newp->w_llist = NULL;
1376 	newp->w_llist_ref = NULL;
1377     }
1378     else
1379 	copy_loclist_stack(oldp, newp);
1380 #endif
1381     newp->w_localdir = (oldp->w_localdir == NULL)
1382 				    ? NULL : vim_strsave(oldp->w_localdir);
1383 
1384     // copy tagstack and folds
1385     for (i = 0; i < oldp->w_tagstacklen; i++)
1386     {
1387 	taggy_T	*tag = &newp->w_tagstack[i];
1388 	*tag = oldp->w_tagstack[i];
1389 	if (tag->tagname != NULL)
1390 	    tag->tagname = vim_strsave(tag->tagname);
1391 	if (tag->user_data != NULL)
1392 	    tag->user_data = vim_strsave(tag->user_data);
1393     }
1394     newp->w_tagstackidx = oldp->w_tagstackidx;
1395     newp->w_tagstacklen = oldp->w_tagstacklen;
1396 #ifdef FEAT_FOLDING
1397     copyFoldingState(oldp, newp);
1398 #endif
1399 
1400     win_init_some(newp, oldp);
1401 
1402 #ifdef FEAT_SYN_HL
1403     check_colorcolumn(newp);
1404 #endif
1405 }
1406 
1407 /*
1408  * Initialize window "newp" from window "old".
1409  * Only the essential things are copied.
1410  */
1411     static void
1412 win_init_some(win_T *newp, win_T *oldp)
1413 {
1414     // Use the same argument list.
1415     newp->w_alist = oldp->w_alist;
1416     ++newp->w_alist->al_refcount;
1417     newp->w_arg_idx = oldp->w_arg_idx;
1418 
1419     // copy options from existing window
1420     win_copy_options(oldp, newp);
1421 }
1422 
1423 /*
1424  * Return TRUE if "win" is a global popup or a popup in the current tab page.
1425  */
1426     int
1427 win_valid_popup(win_T *win UNUSED)
1428 {
1429 #ifdef FEAT_PROP_POPUP
1430     win_T	*wp;
1431 
1432     FOR_ALL_POPUPWINS(wp)
1433 	if (wp == win)
1434 	    return TRUE;
1435     FOR_ALL_POPUPWINS_IN_TAB(curtab, wp)
1436 	if (wp == win)
1437 	    return TRUE;
1438 #endif
1439     return FALSE;
1440 }
1441 
1442 /*
1443  * Check if "win" is a pointer to an existing window in the current tab page.
1444  */
1445     int
1446 win_valid(win_T *win)
1447 {
1448     win_T	*wp;
1449 
1450     if (win == NULL)
1451 	return FALSE;
1452     FOR_ALL_WINDOWS(wp)
1453 	if (wp == win)
1454 	    return TRUE;
1455     return win_valid_popup(win);
1456 }
1457 
1458 /*
1459  * Check if "win" is a pointer to an existing window in any tab page.
1460  */
1461     int
1462 win_valid_any_tab(win_T *win)
1463 {
1464     win_T	*wp;
1465     tabpage_T	*tp;
1466 
1467     if (win == NULL)
1468 	return FALSE;
1469     FOR_ALL_TABPAGES(tp)
1470     {
1471 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
1472 	{
1473 	    if (wp == win)
1474 		return TRUE;
1475 	}
1476 #ifdef FEAT_PROP_POPUP
1477 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
1478 	    if (wp == win)
1479 		return TRUE;
1480 #endif
1481     }
1482     return win_valid_popup(win);
1483 }
1484 
1485 /*
1486  * Return the number of windows.
1487  */
1488     int
1489 win_count(void)
1490 {
1491     win_T	*wp;
1492     int		count = 0;
1493 
1494     FOR_ALL_WINDOWS(wp)
1495 	++count;
1496     return count;
1497 }
1498 
1499 /*
1500  * Make "count" windows on the screen.
1501  * Return actual number of windows on the screen.
1502  * Must be called when there is just one window, filling the whole screen
1503  * (excluding the command line).
1504  */
1505     int
1506 make_windows(
1507     int		count,
1508     int		vertical UNUSED)  // split windows vertically if TRUE
1509 {
1510     int		maxcount;
1511     int		todo;
1512 
1513     if (vertical)
1514     {
1515 	// Each windows needs at least 'winminwidth' lines and a separator
1516 	// column.
1517 	maxcount = (curwin->w_width + curwin->w_vsep_width
1518 					     - (p_wiw - p_wmw)) / (p_wmw + 1);
1519     }
1520     else
1521     {
1522 	// Each window needs at least 'winminheight' lines and a status line.
1523 	maxcount = (VISIBLE_HEIGHT(curwin) + curwin->w_status_height
1524 				  - (p_wh - p_wmh)) / (p_wmh + STATUS_HEIGHT);
1525     }
1526 
1527     if (maxcount < 2)
1528 	maxcount = 2;
1529     if (count > maxcount)
1530 	count = maxcount;
1531 
1532     /*
1533      * add status line now, otherwise first window will be too big
1534      */
1535     if (count > 1)
1536 	last_status(TRUE);
1537 
1538     /*
1539      * Don't execute autocommands while creating the windows.  Must do that
1540      * when putting the buffers in the windows.
1541      */
1542     block_autocmds();
1543 
1544     // todo is number of windows left to create
1545     for (todo = count - 1; todo > 0; --todo)
1546 	if (vertical)
1547 	{
1548 	    if (win_split(curwin->w_width - (curwin->w_width - todo)
1549 			/ (todo + 1) - 1, WSP_VERT | WSP_ABOVE) == FAIL)
1550 		break;
1551 	}
1552 	else
1553 	{
1554 	    if (win_split(curwin->w_height - (curwin->w_height - todo
1555 			    * STATUS_HEIGHT) / (todo + 1)
1556 			- STATUS_HEIGHT, WSP_ABOVE) == FAIL)
1557 		break;
1558 	}
1559 
1560     unblock_autocmds();
1561 
1562     // return actual number of windows
1563     return (count - todo);
1564 }
1565 
1566 /*
1567  * Exchange current and next window
1568  */
1569     static void
1570 win_exchange(long Prenum)
1571 {
1572     frame_T	*frp;
1573     frame_T	*frp2;
1574     win_T	*wp;
1575     win_T	*wp2;
1576     int		temp;
1577 
1578     if (ERROR_IF_ANY_POPUP_WINDOW)
1579 	return;
1580     if (ONE_WINDOW)	    // just one window
1581     {
1582 	beep_flush();
1583 	return;
1584     }
1585 
1586 #ifdef FEAT_GUI
1587     need_mouse_correct = TRUE;
1588 #endif
1589 
1590     /*
1591      * find window to exchange with
1592      */
1593     if (Prenum)
1594     {
1595 	frp = curwin->w_frame->fr_parent->fr_child;
1596 	while (frp != NULL && --Prenum > 0)
1597 	    frp = frp->fr_next;
1598     }
1599     else if (curwin->w_frame->fr_next != NULL)	// Swap with next
1600 	frp = curwin->w_frame->fr_next;
1601     else    // Swap last window in row/col with previous
1602 	frp = curwin->w_frame->fr_prev;
1603 
1604     // We can only exchange a window with another window, not with a frame
1605     // containing windows.
1606     if (frp == NULL || frp->fr_win == NULL || frp->fr_win == curwin)
1607 	return;
1608     wp = frp->fr_win;
1609 
1610 /*
1611  * 1. remove curwin from the list. Remember after which window it was in wp2
1612  * 2. insert curwin before wp in the list
1613  * if wp != wp2
1614  *    3. remove wp from the list
1615  *    4. insert wp after wp2
1616  * 5. exchange the status line height and vsep width.
1617  */
1618     wp2 = curwin->w_prev;
1619     frp2 = curwin->w_frame->fr_prev;
1620     if (wp->w_prev != curwin)
1621     {
1622 	win_remove(curwin, NULL);
1623 	frame_remove(curwin->w_frame);
1624 	win_append(wp->w_prev, curwin);
1625 	frame_insert(frp, curwin->w_frame);
1626     }
1627     if (wp != wp2)
1628     {
1629 	win_remove(wp, NULL);
1630 	frame_remove(wp->w_frame);
1631 	win_append(wp2, wp);
1632 	if (frp2 == NULL)
1633 	    frame_insert(wp->w_frame->fr_parent->fr_child, wp->w_frame);
1634 	else
1635 	    frame_append(frp2, wp->w_frame);
1636     }
1637     temp = curwin->w_status_height;
1638     curwin->w_status_height = wp->w_status_height;
1639     wp->w_status_height = temp;
1640     temp = curwin->w_vsep_width;
1641     curwin->w_vsep_width = wp->w_vsep_width;
1642     wp->w_vsep_width = temp;
1643 
1644     // If the windows are not in the same frame, exchange the sizes to avoid
1645     // messing up the window layout.  Otherwise fix the frame sizes.
1646     if (curwin->w_frame->fr_parent != wp->w_frame->fr_parent)
1647     {
1648 	temp = curwin->w_height;
1649 	curwin->w_height = wp->w_height;
1650 	wp->w_height = temp;
1651 	temp = curwin->w_width;
1652 	curwin->w_width = wp->w_width;
1653 	wp->w_width = temp;
1654     }
1655     else
1656     {
1657 	frame_fix_height(curwin);
1658 	frame_fix_height(wp);
1659 	frame_fix_width(curwin);
1660 	frame_fix_width(wp);
1661     }
1662 
1663     (void)win_comp_pos();		// recompute window positions
1664 
1665     win_enter(wp, TRUE);
1666     redraw_all_later(NOT_VALID);
1667 }
1668 
1669 /*
1670  * rotate windows: if upwards TRUE the second window becomes the first one
1671  *		   if upwards FALSE the first window becomes the second one
1672  */
1673     static void
1674 win_rotate(int upwards, int count)
1675 {
1676     win_T	*wp1;
1677     win_T	*wp2;
1678     frame_T	*frp;
1679     int		n;
1680 
1681     if (ONE_WINDOW)		// nothing to do
1682     {
1683 	beep_flush();
1684 	return;
1685     }
1686 
1687 #ifdef FEAT_GUI
1688     need_mouse_correct = TRUE;
1689 #endif
1690 
1691     // Check if all frames in this row/col have one window.
1692     FOR_ALL_FRAMES(frp, curwin->w_frame->fr_parent->fr_child)
1693 	if (frp->fr_win == NULL)
1694 	{
1695 	    emsg(_("E443: Cannot rotate when another window is split"));
1696 	    return;
1697 	}
1698 
1699     while (count--)
1700     {
1701 	if (upwards)		// first window becomes last window
1702 	{
1703 	    // remove first window/frame from the list
1704 	    frp = curwin->w_frame->fr_parent->fr_child;
1705 	    wp1 = frp->fr_win;
1706 	    win_remove(wp1, NULL);
1707 	    frame_remove(frp);
1708 
1709 	    // find last frame and append removed window/frame after it
1710 	    for ( ; frp->fr_next != NULL; frp = frp->fr_next)
1711 		;
1712 	    win_append(frp->fr_win, wp1);
1713 	    frame_append(frp, wp1->w_frame);
1714 
1715 	    wp2 = frp->fr_win;		// previously last window
1716 	}
1717 	else			// last window becomes first window
1718 	{
1719 	    // find last window/frame in the list and remove it
1720 	    for (frp = curwin->w_frame; frp->fr_next != NULL;
1721 							   frp = frp->fr_next)
1722 		;
1723 	    wp1 = frp->fr_win;
1724 	    wp2 = wp1->w_prev;		    // will become last window
1725 	    win_remove(wp1, NULL);
1726 	    frame_remove(frp);
1727 
1728 	    // append the removed window/frame before the first in the list
1729 	    win_append(frp->fr_parent->fr_child->fr_win->w_prev, wp1);
1730 	    frame_insert(frp->fr_parent->fr_child, frp);
1731 	}
1732 
1733 	// exchange status height and vsep width of old and new last window
1734 	n = wp2->w_status_height;
1735 	wp2->w_status_height = wp1->w_status_height;
1736 	wp1->w_status_height = n;
1737 	frame_fix_height(wp1);
1738 	frame_fix_height(wp2);
1739 	n = wp2->w_vsep_width;
1740 	wp2->w_vsep_width = wp1->w_vsep_width;
1741 	wp1->w_vsep_width = n;
1742 	frame_fix_width(wp1);
1743 	frame_fix_width(wp2);
1744 
1745 	// recompute w_winrow and w_wincol for all windows
1746 	(void)win_comp_pos();
1747     }
1748 
1749     redraw_all_later(NOT_VALID);
1750 }
1751 
1752 /*
1753  * Move the current window to the very top/bottom/left/right of the screen.
1754  */
1755     static void
1756 win_totop(int size, int flags)
1757 {
1758     int		dir;
1759     int		height = curwin->w_height;
1760 
1761     if (ONE_WINDOW)
1762     {
1763 	beep_flush();
1764 	return;
1765     }
1766     if (check_split_disallowed() == FAIL)
1767 	return;
1768 
1769     // Remove the window and frame from the tree of frames.
1770     (void)winframe_remove(curwin, &dir, NULL);
1771     win_remove(curwin, NULL);
1772     last_status(FALSE);	    // may need to remove last status line
1773     (void)win_comp_pos();   // recompute window positions
1774 
1775     // Split a window on the desired side and put the window there.
1776     (void)win_split_ins(size, flags, curwin, dir);
1777     if (!(flags & WSP_VERT))
1778     {
1779 	win_setheight(height);
1780 	if (p_ea)
1781 	    win_equal(curwin, TRUE, 'v');
1782     }
1783 
1784 #if defined(FEAT_GUI)
1785     // When 'guioptions' includes 'L' or 'R' may have to remove or add
1786     // scrollbars.  Have to update them anyway.
1787     gui_may_update_scrollbars();
1788 #endif
1789 }
1790 
1791 /*
1792  * Move window "win1" to below/right of "win2" and make "win1" the current
1793  * window.  Only works within the same frame!
1794  */
1795     void
1796 win_move_after(win_T *win1, win_T *win2)
1797 {
1798     int		height;
1799 
1800     // check if the arguments are reasonable
1801     if (win1 == win2)
1802 	return;
1803 
1804     // check if there is something to do
1805     if (win2->w_next != win1)
1806     {
1807 	if (win1->w_frame->fr_parent != win2->w_frame->fr_parent)
1808 	{
1809 	    iemsg("INTERNAL: trying to move a window into another frame");
1810 	    return;
1811 	}
1812 
1813 	// may need to move the status line/vertical separator of the last
1814 	// window
1815 	if (win1 == lastwin)
1816 	{
1817 	    height = win1->w_prev->w_status_height;
1818 	    win1->w_prev->w_status_height = win1->w_status_height;
1819 	    win1->w_status_height = height;
1820 	    if (win1->w_prev->w_vsep_width == 1)
1821 	    {
1822 		// Remove the vertical separator from the last-but-one window,
1823 		// add it to the last window.  Adjust the frame widths.
1824 		win1->w_prev->w_vsep_width = 0;
1825 		win1->w_prev->w_frame->fr_width -= 1;
1826 		win1->w_vsep_width = 1;
1827 		win1->w_frame->fr_width += 1;
1828 	    }
1829 	}
1830 	else if (win2 == lastwin)
1831 	{
1832 	    height = win1->w_status_height;
1833 	    win1->w_status_height = win2->w_status_height;
1834 	    win2->w_status_height = height;
1835 	    if (win1->w_vsep_width == 1)
1836 	    {
1837 		// Remove the vertical separator from win1, add it to the last
1838 		// window, win2.  Adjust the frame widths.
1839 		win2->w_vsep_width = 1;
1840 		win2->w_frame->fr_width += 1;
1841 		win1->w_vsep_width = 0;
1842 		win1->w_frame->fr_width -= 1;
1843 	    }
1844 	}
1845 	win_remove(win1, NULL);
1846 	frame_remove(win1->w_frame);
1847 	win_append(win2, win1);
1848 	frame_append(win2->w_frame, win1->w_frame);
1849 
1850 	(void)win_comp_pos();	// recompute w_winrow for all windows
1851 	redraw_later(NOT_VALID);
1852     }
1853     win_enter(win1, FALSE);
1854 }
1855 
1856 /*
1857  * Make all windows the same height.
1858  * 'next_curwin' will soon be the current window, make sure it has enough
1859  * rows.
1860  */
1861     void
1862 win_equal(
1863     win_T	*next_curwin,	// pointer to current window to be or NULL
1864     int		current,	// do only frame with current window
1865     int		dir)		// 'v' for vertically, 'h' for horizontally,
1866 				// 'b' for both, 0 for using p_ead
1867 {
1868     if (dir == 0)
1869 	dir = *p_ead;
1870     win_equal_rec(next_curwin == NULL ? curwin : next_curwin, current,
1871 		      topframe, dir, 0, tabline_height(),
1872 					   (int)Columns, topframe->fr_height);
1873 }
1874 
1875 /*
1876  * Set a frame to a new position and height, spreading the available room
1877  * equally over contained frames.
1878  * The window "next_curwin" (if not NULL) should at least get the size from
1879  * 'winheight' and 'winwidth' if possible.
1880  */
1881     static void
1882 win_equal_rec(
1883     win_T	*next_curwin,	// pointer to current window to be or NULL
1884     int		current,	// do only frame with current window
1885     frame_T	*topfr,		// frame to set size off
1886     int		dir,		// 'v', 'h' or 'b', see win_equal()
1887     int		col,		// horizontal position for frame
1888     int		row,		// vertical position for frame
1889     int		width,		// new width of frame
1890     int		height)		// new height of frame
1891 {
1892     int		n, m;
1893     int		extra_sep = 0;
1894     int		wincount, totwincount = 0;
1895     frame_T	*fr;
1896     int		next_curwin_size = 0;
1897     int		room = 0;
1898     int		new_size;
1899     int		has_next_curwin = 0;
1900     int		hnc;
1901 
1902     if (topfr->fr_layout == FR_LEAF)
1903     {
1904 	// Set the width/height of this frame.
1905 	// Redraw when size or position changes
1906 	if (topfr->fr_height != height || topfr->fr_win->w_winrow != row
1907 		|| topfr->fr_width != width || topfr->fr_win->w_wincol != col
1908 	   )
1909 	{
1910 	    topfr->fr_win->w_winrow = row;
1911 	    frame_new_height(topfr, height, FALSE, FALSE);
1912 	    topfr->fr_win->w_wincol = col;
1913 	    frame_new_width(topfr, width, FALSE, FALSE);
1914 	    redraw_all_later(NOT_VALID);
1915 	}
1916     }
1917     else if (topfr->fr_layout == FR_ROW)
1918     {
1919 	topfr->fr_width = width;
1920 	topfr->fr_height = height;
1921 
1922 	if (dir != 'v')			// equalize frame widths
1923 	{
1924 	    // Compute the maximum number of windows horizontally in this
1925 	    // frame.
1926 	    n = frame_minwidth(topfr, NOWIN);
1927 	    // add one for the rightmost window, it doesn't have a separator
1928 	    if (col + width == Columns)
1929 		extra_sep = 1;
1930 	    else
1931 		extra_sep = 0;
1932 	    totwincount = (n + extra_sep) / (p_wmw + 1);
1933 	    has_next_curwin = frame_has_win(topfr, next_curwin);
1934 
1935 	    /*
1936 	     * Compute width for "next_curwin" window and room available for
1937 	     * other windows.
1938 	     * "m" is the minimal width when counting p_wiw for "next_curwin".
1939 	     */
1940 	    m = frame_minwidth(topfr, next_curwin);
1941 	    room = width - m;
1942 	    if (room < 0)
1943 	    {
1944 		next_curwin_size = p_wiw + room;
1945 		room = 0;
1946 	    }
1947 	    else
1948 	    {
1949 		next_curwin_size = -1;
1950 		FOR_ALL_FRAMES(fr, topfr->fr_child)
1951 		{
1952 		    // If 'winfixwidth' set keep the window width if
1953 		    // possible.
1954 		    // Watch out for this window being the next_curwin.
1955 		    if (frame_fixed_width(fr))
1956 		    {
1957 			n = frame_minwidth(fr, NOWIN);
1958 			new_size = fr->fr_width;
1959 			if (frame_has_win(fr, next_curwin))
1960 			{
1961 			    room += p_wiw - p_wmw;
1962 			    next_curwin_size = 0;
1963 			    if (new_size < p_wiw)
1964 				new_size = p_wiw;
1965 			}
1966 			else
1967 			    // These windows don't use up room.
1968 			    totwincount -= (n + (fr->fr_next == NULL
1969 					      ? extra_sep : 0)) / (p_wmw + 1);
1970 			room -= new_size - n;
1971 			if (room < 0)
1972 			{
1973 			    new_size += room;
1974 			    room = 0;
1975 			}
1976 			fr->fr_newwidth = new_size;
1977 		    }
1978 		}
1979 		if (next_curwin_size == -1)
1980 		{
1981 		    if (!has_next_curwin)
1982 			next_curwin_size = 0;
1983 		    else if (totwincount > 1
1984 			    && (room + (totwincount - 2))
1985 						  / (totwincount - 1) > p_wiw)
1986 		    {
1987 			// Can make all windows wider than 'winwidth', spread
1988 			// the room equally.
1989 			next_curwin_size = (room + p_wiw
1990 					    + (totwincount - 1) * p_wmw
1991 					    + (totwincount - 1)) / totwincount;
1992 			room -= next_curwin_size - p_wiw;
1993 		    }
1994 		    else
1995 			next_curwin_size = p_wiw;
1996 		}
1997 	    }
1998 
1999 	    if (has_next_curwin)
2000 		--totwincount;		// don't count curwin
2001 	}
2002 
2003 	FOR_ALL_FRAMES(fr, topfr->fr_child)
2004 	{
2005 	    wincount = 1;
2006 	    if (fr->fr_next == NULL)
2007 		// last frame gets all that remains (avoid roundoff error)
2008 		new_size = width;
2009 	    else if (dir == 'v')
2010 		new_size = fr->fr_width;
2011 	    else if (frame_fixed_width(fr))
2012 	    {
2013 		new_size = fr->fr_newwidth;
2014 		wincount = 0;	    // doesn't count as a sizeable window
2015 	    }
2016 	    else
2017 	    {
2018 		// Compute the maximum number of windows horiz. in "fr".
2019 		n = frame_minwidth(fr, NOWIN);
2020 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2021 								/ (p_wmw + 1);
2022 		m = frame_minwidth(fr, next_curwin);
2023 		if (has_next_curwin)
2024 		    hnc = frame_has_win(fr, next_curwin);
2025 		else
2026 		    hnc = FALSE;
2027 		if (hnc)	    // don't count next_curwin
2028 		    --wincount;
2029 		if (totwincount == 0)
2030 		    new_size = room;
2031 		else
2032 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2033 								/ totwincount;
2034 		if (hnc)	    // add next_curwin size
2035 		{
2036 		    next_curwin_size -= p_wiw - (m - n);
2037 		    new_size += next_curwin_size;
2038 		    room -= new_size - next_curwin_size;
2039 		}
2040 		else
2041 		    room -= new_size;
2042 		new_size += n;
2043 	    }
2044 
2045 	    // Skip frame that is full width when splitting or closing a
2046 	    // window, unless equalizing all frames.
2047 	    if (!current || dir != 'v' || topfr->fr_parent != NULL
2048 		    || (new_size != fr->fr_width)
2049 		    || frame_has_win(fr, next_curwin))
2050 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2051 							    new_size, height);
2052 	    col += new_size;
2053 	    width -= new_size;
2054 	    totwincount -= wincount;
2055 	}
2056     }
2057     else // topfr->fr_layout == FR_COL
2058     {
2059 	topfr->fr_width = width;
2060 	topfr->fr_height = height;
2061 
2062 	if (dir != 'h')			// equalize frame heights
2063 	{
2064 	    // Compute maximum number of windows vertically in this frame.
2065 	    n = frame_minheight(topfr, NOWIN);
2066 	    // add one for the bottom window if it doesn't have a statusline
2067 	    if (row + height == cmdline_row && p_ls == 0)
2068 		extra_sep = 1;
2069 	    else
2070 		extra_sep = 0;
2071 	    totwincount = (n + extra_sep) / (p_wmh + 1);
2072 	    has_next_curwin = frame_has_win(topfr, next_curwin);
2073 
2074 	    /*
2075 	     * Compute height for "next_curwin" window and room available for
2076 	     * other windows.
2077 	     * "m" is the minimal height when counting p_wh for "next_curwin".
2078 	     */
2079 	    m = frame_minheight(topfr, next_curwin);
2080 	    room = height - m;
2081 	    if (room < 0)
2082 	    {
2083 		// The room is less then 'winheight', use all space for the
2084 		// current window.
2085 		next_curwin_size = p_wh + room;
2086 		room = 0;
2087 	    }
2088 	    else
2089 	    {
2090 		next_curwin_size = -1;
2091 		FOR_ALL_FRAMES(fr, topfr->fr_child)
2092 		{
2093 		    // If 'winfixheight' set keep the window height if
2094 		    // possible.
2095 		    // Watch out for this window being the next_curwin.
2096 		    if (frame_fixed_height(fr))
2097 		    {
2098 			n = frame_minheight(fr, NOWIN);
2099 			new_size = fr->fr_height;
2100 			if (frame_has_win(fr, next_curwin))
2101 			{
2102 			    room += p_wh - p_wmh;
2103 			    next_curwin_size = 0;
2104 			    if (new_size < p_wh)
2105 				new_size = p_wh;
2106 			}
2107 			else
2108 			    // These windows don't use up room.
2109 			    totwincount -= (n + (fr->fr_next == NULL
2110 					      ? extra_sep : 0)) / (p_wmh + 1);
2111 			room -= new_size - n;
2112 			if (room < 0)
2113 			{
2114 			    new_size += room;
2115 			    room = 0;
2116 			}
2117 			fr->fr_newheight = new_size;
2118 		    }
2119 		}
2120 		if (next_curwin_size == -1)
2121 		{
2122 		    if (!has_next_curwin)
2123 			next_curwin_size = 0;
2124 		    else if (totwincount > 1
2125 			    && (room + (totwincount - 2))
2126 						   / (totwincount - 1) > p_wh)
2127 		    {
2128 			// can make all windows higher than 'winheight',
2129 			// spread the room equally.
2130 			next_curwin_size = (room + p_wh
2131 					   + (totwincount - 1) * p_wmh
2132 					   + (totwincount - 1)) / totwincount;
2133 			room -= next_curwin_size - p_wh;
2134 		    }
2135 		    else
2136 			next_curwin_size = p_wh;
2137 		}
2138 	    }
2139 
2140 	    if (has_next_curwin)
2141 		--totwincount;		// don't count curwin
2142 	}
2143 
2144 	FOR_ALL_FRAMES(fr, topfr->fr_child)
2145 	{
2146 	    wincount = 1;
2147 	    if (fr->fr_next == NULL)
2148 		// last frame gets all that remains (avoid roundoff error)
2149 		new_size = height;
2150 	    else if (dir == 'h')
2151 		new_size = fr->fr_height;
2152 	    else if (frame_fixed_height(fr))
2153 	    {
2154 		new_size = fr->fr_newheight;
2155 		wincount = 0;	    // doesn't count as a sizeable window
2156 	    }
2157 	    else
2158 	    {
2159 		// Compute the maximum number of windows vert. in "fr".
2160 		n = frame_minheight(fr, NOWIN);
2161 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2162 								/ (p_wmh + 1);
2163 		m = frame_minheight(fr, next_curwin);
2164 		if (has_next_curwin)
2165 		    hnc = frame_has_win(fr, next_curwin);
2166 		else
2167 		    hnc = FALSE;
2168 		if (hnc)	    // don't count next_curwin
2169 		    --wincount;
2170 		if (totwincount == 0)
2171 		    new_size = room;
2172 		else
2173 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2174 								/ totwincount;
2175 		if (hnc)	    // add next_curwin size
2176 		{
2177 		    next_curwin_size -= p_wh - (m - n);
2178 		    new_size += next_curwin_size;
2179 		    room -= new_size - next_curwin_size;
2180 		}
2181 		else
2182 		    room -= new_size;
2183 		new_size += n;
2184 	    }
2185 	    // Skip frame that is full width when splitting or closing a
2186 	    // window, unless equalizing all frames.
2187 	    if (!current || dir != 'h' || topfr->fr_parent != NULL
2188 		    || (new_size != fr->fr_height)
2189 		    || frame_has_win(fr, next_curwin))
2190 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2191 							     width, new_size);
2192 	    row += new_size;
2193 	    height -= new_size;
2194 	    totwincount -= wincount;
2195 	}
2196     }
2197 }
2198 
2199 #ifdef FEAT_JOB_CHANNEL
2200     static void
2201 leaving_window(win_T *win)
2202 {
2203     // Only matters for a prompt window.
2204     if (!bt_prompt(win->w_buffer))
2205 	return;
2206 
2207     // When leaving a prompt window stop Insert mode and perhaps restart
2208     // it when entering that window again.
2209     win->w_buffer->b_prompt_insert = restart_edit;
2210     if (restart_edit != 0 && mode_displayed)
2211 	clear_cmdline = TRUE;		// unshow mode later
2212     restart_edit = NUL;
2213 
2214     // When leaving the window (or closing the window) was done from a
2215     // callback we need to break out of the Insert mode loop and restart Insert
2216     // mode when entering the window again.
2217     if (State & INSERT)
2218     {
2219 	stop_insert_mode = TRUE;
2220 	if (win->w_buffer->b_prompt_insert == NUL)
2221 	    win->w_buffer->b_prompt_insert = 'A';
2222     }
2223 }
2224 
2225     static void
2226 entering_window(win_T *win)
2227 {
2228     // Only matters for a prompt window.
2229     if (!bt_prompt(win->w_buffer))
2230 	return;
2231 
2232     // When switching to a prompt buffer that was in Insert mode, don't stop
2233     // Insert mode, it may have been set in leaving_window().
2234     if (win->w_buffer->b_prompt_insert != NUL)
2235 	stop_insert_mode = FALSE;
2236 
2237     // When entering the prompt window restart Insert mode if we were in Insert
2238     // mode when we left it.
2239     restart_edit = win->w_buffer->b_prompt_insert;
2240 }
2241 #endif
2242 
2243 /*
2244  * Close all windows for buffer "buf".
2245  */
2246     void
2247 close_windows(
2248     buf_T	*buf,
2249     int		keep_curwin)	    // don't close "curwin"
2250 {
2251     win_T	*wp;
2252     tabpage_T   *tp, *nexttp;
2253     int		h = tabline_height();
2254     int		count = tabpage_index(NULL);
2255 
2256     ++RedrawingDisabled;
2257 
2258     for (wp = firstwin; wp != NULL && !ONE_WINDOW; )
2259     {
2260 	if (wp->w_buffer == buf && (!keep_curwin || wp != curwin)
2261 		&& !(wp->w_closing || wp->w_buffer->b_locked > 0))
2262 	{
2263 	    if (win_close(wp, FALSE) == FAIL)
2264 		// If closing the window fails give up, to avoid looping
2265 		// forever.
2266 		break;
2267 
2268 	    // Start all over, autocommands may change the window layout.
2269 	    wp = firstwin;
2270 	}
2271 	else
2272 	    wp = wp->w_next;
2273     }
2274 
2275     // Also check windows in other tab pages.
2276     for (tp = first_tabpage; tp != NULL; tp = nexttp)
2277     {
2278 	nexttp = tp->tp_next;
2279 	if (tp != curtab)
2280 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
2281 		if (wp->w_buffer == buf
2282 		    && !(wp->w_closing || wp->w_buffer->b_locked > 0))
2283 		{
2284 		    win_close_othertab(wp, FALSE, tp);
2285 
2286 		    // Start all over, the tab page may be closed and
2287 		    // autocommands may change the window layout.
2288 		    nexttp = first_tabpage;
2289 		    break;
2290 		}
2291     }
2292 
2293     --RedrawingDisabled;
2294 
2295     if (count != tabpage_index(NULL))
2296 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2297 
2298     redraw_tabline = TRUE;
2299     if (h != tabline_height())
2300 	shell_new_rows();
2301 }
2302 
2303 /*
2304  * Return TRUE if the current window is the only window that exists (ignoring
2305  * "aucmd_win").
2306  * Returns FALSE if there is a window, possibly in another tab page.
2307  */
2308     static int
2309 last_window(void)
2310 {
2311     return (one_window() && first_tabpage->tp_next == NULL);
2312 }
2313 
2314 /*
2315  * Return TRUE if there is only one window other than "aucmd_win" in the
2316  * current tab page.
2317  */
2318     int
2319 one_window(void)
2320 {
2321     win_T	*wp;
2322     int		seen_one = FALSE;
2323 
2324     FOR_ALL_WINDOWS(wp)
2325     {
2326 	if (wp != aucmd_win)
2327 	{
2328 	    if (seen_one)
2329 		return FALSE;
2330 	    seen_one = TRUE;
2331 	}
2332     }
2333     return TRUE;
2334 }
2335 
2336 /*
2337  * Close the possibly last window in a tab page.
2338  * Returns TRUE when the window was closed already.
2339  */
2340     static int
2341 close_last_window_tabpage(
2342     win_T	*win,
2343     int		free_buf,
2344     tabpage_T   *prev_curtab)
2345 {
2346     if (ONE_WINDOW)
2347     {
2348 	buf_T	*old_curbuf = curbuf;
2349 
2350 	/*
2351 	 * Closing the last window in a tab page.  First go to another tab
2352 	 * page and then close the window and the tab page.  This avoids that
2353 	 * curwin and curtab are invalid while we are freeing memory, they may
2354 	 * be used in GUI events.
2355 	 * Don't trigger autocommands yet, they may use wrong values, so do
2356 	 * that below.
2357 	 */
2358 	goto_tabpage_tp(alt_tabpage(), FALSE, TRUE);
2359 	redraw_tabline = TRUE;
2360 
2361 	// Safety check: Autocommands may have closed the window when jumping
2362 	// to the other tab page.
2363 	if (valid_tabpage(prev_curtab) && prev_curtab->tp_firstwin == win)
2364 	{
2365 	    int	    h = tabline_height();
2366 
2367 	    win_close_othertab(win, free_buf, prev_curtab);
2368 	    if (h != tabline_height())
2369 		shell_new_rows();
2370 	}
2371 #ifdef FEAT_JOB_CHANNEL
2372 	entering_window(curwin);
2373 #endif
2374 	// Since goto_tabpage_tp above did not trigger *Enter autocommands, do
2375 	// that now.
2376 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2377 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
2378 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
2379 	if (old_curbuf != curbuf)
2380 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2381 	return TRUE;
2382     }
2383     return FALSE;
2384 }
2385 
2386 /*
2387  * Close the buffer of "win" and unload it if "action" is DOBUF_UNLOAD.
2388  * "action" can also be zero (do nothing) or DOBUF_WIPE.
2389  * "abort_if_last" is passed to close_buffer(): abort closing if all other
2390  * windows are closed.
2391  */
2392     static void
2393 win_close_buffer(win_T *win, int action, int abort_if_last)
2394 {
2395 #ifdef FEAT_SYN_HL
2396     // Free independent synblock before the buffer is freed.
2397     if (win->w_buffer != NULL)
2398 	reset_synblock(win);
2399 #endif
2400 
2401 #ifdef FEAT_QUICKFIX
2402     // When the quickfix/location list window is closed, unlist the buffer.
2403     if (win->w_buffer != NULL && bt_quickfix(win->w_buffer))
2404 	win->w_buffer->b_p_bl = FALSE;
2405 #endif
2406 
2407     // Close the link to the buffer.
2408     if (win->w_buffer != NULL)
2409     {
2410 	bufref_T    bufref;
2411 
2412 	set_bufref(&bufref, curbuf);
2413 	win->w_closing = TRUE;
2414 	close_buffer(win, win->w_buffer, action, abort_if_last, FALSE);
2415 	if (win_valid_any_tab(win))
2416 	    win->w_closing = FALSE;
2417 	// Make sure curbuf is valid. It can become invalid if 'bufhidden' is
2418 	// "wipe".
2419 	if (!bufref_valid(&bufref))
2420 	    curbuf = firstbuf;
2421     }
2422 }
2423 
2424 /*
2425  * Close window "win".  Only works for the current tab page.
2426  * If "free_buf" is TRUE related buffer may be unloaded.
2427  *
2428  * Called by :quit, :close, :xit, :wq and findtag().
2429  * Returns FAIL when the window was not closed.
2430  */
2431     int
2432 win_close(win_T *win, int free_buf)
2433 {
2434     win_T	*wp;
2435     int		other_buffer = FALSE;
2436     int		close_curwin = FALSE;
2437     int		dir;
2438     int		help_window = FALSE;
2439     tabpage_T   *prev_curtab = curtab;
2440     frame_T	*win_frame = win->w_frame->fr_parent;
2441 #ifdef FEAT_DIFF
2442     int		had_diffmode = win->w_p_diff;
2443 #endif
2444 
2445 #if defined(FEAT_TERMINAL) && defined(FEAT_PROP_POPUP)
2446     // Can close a popup window with a terminal if the job has finished.
2447     if (may_close_term_popup() == OK)
2448 	return OK;
2449 #endif
2450     if (ERROR_IF_ANY_POPUP_WINDOW)
2451 	return FAIL;
2452 
2453     if (last_window())
2454     {
2455 	emsg(_("E444: Cannot close last window"));
2456 	return FAIL;
2457     }
2458 
2459     if (win->w_closing || (win->w_buffer != NULL
2460 					       && win->w_buffer->b_locked > 0))
2461 	return FAIL; // window is already being closed
2462     if (win_unlisted(win))
2463     {
2464 	emsg(_(e_autocmd_close));
2465 	return FAIL;
2466     }
2467     if ((firstwin == aucmd_win || lastwin == aucmd_win) && one_window())
2468     {
2469 	emsg(_("E814: Cannot close window, only autocmd window would remain"));
2470 	return FAIL;
2471     }
2472 
2473     // When closing the last window in a tab page first go to another tab page
2474     // and then close the window and the tab page to avoid that curwin and
2475     // curtab are invalid while we are freeing memory.
2476     if (close_last_window_tabpage(win, free_buf, prev_curtab))
2477       return FAIL;
2478 
2479     // When closing the help window, try restoring a snapshot after closing
2480     // the window.  Otherwise clear the snapshot, it's now invalid.
2481     if (bt_help(win->w_buffer))
2482 	help_window = TRUE;
2483     else
2484 	clear_snapshot(curtab, SNAP_HELP_IDX);
2485 
2486     if (win == curwin)
2487     {
2488 #ifdef FEAT_JOB_CHANNEL
2489 	leaving_window(curwin);
2490 #endif
2491 	/*
2492 	 * Guess which window is going to be the new current window.
2493 	 * This may change because of the autocommands (sigh).
2494 	 */
2495 	wp = frame2win(win_altframe(win, NULL));
2496 
2497 	/*
2498 	 * Be careful: If autocommands delete the window or cause this window
2499 	 * to be the last one left, return now.
2500 	 */
2501 	if (wp->w_buffer != curbuf)
2502 	{
2503 	    other_buffer = TRUE;
2504 	    win->w_closing = TRUE;
2505 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
2506 	    if (!win_valid(win))
2507 		return FAIL;
2508 	    win->w_closing = FALSE;
2509 	    if (last_window())
2510 		return FAIL;
2511 	}
2512 	win->w_closing = TRUE;
2513 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
2514 	if (!win_valid(win))
2515 	    return FAIL;
2516 	win->w_closing = FALSE;
2517 	if (last_window())
2518 	    return FAIL;
2519 #ifdef FEAT_EVAL
2520 	// autocmds may abort script processing
2521 	if (aborting())
2522 	    return FAIL;
2523 #endif
2524     }
2525 
2526 #ifdef FEAT_GUI
2527     // Avoid trouble with scrollbars that are going to be deleted in
2528     // win_free().
2529     if (gui.in_use)
2530 	out_flush();
2531 #endif
2532 
2533 #ifdef FEAT_PROP_POPUP
2534     if (popup_win_closed(win) && !win_valid(win))
2535 	return FAIL;
2536 #endif
2537     win_close_buffer(win, free_buf ? DOBUF_UNLOAD : 0, TRUE);
2538 
2539     if (only_one_window() && win_valid(win) && win->w_buffer == NULL
2540 	    && (last_window() || curtab != prev_curtab
2541 		|| close_last_window_tabpage(win, free_buf, prev_curtab)))
2542     {
2543 	// Autocommands have closed all windows, quit now.  Restore
2544 	// curwin->w_buffer, otherwise writing viminfo may fail.
2545 	if (curwin->w_buffer == NULL)
2546 	    curwin->w_buffer = curbuf;
2547 	getout(0);
2548     }
2549 
2550     // Autocommands may have moved to another tab page.
2551     if (curtab != prev_curtab && win_valid_any_tab(win)
2552 						      && win->w_buffer == NULL)
2553     {
2554 	// Need to close the window anyway, since the buffer is NULL.
2555 	win_close_othertab(win, FALSE, prev_curtab);
2556 	return FAIL;
2557     }
2558 
2559     // Autocommands may have closed the window already or closed the only
2560     // other window.
2561     if (!win_valid(win) || last_window()
2562 	    || close_last_window_tabpage(win, free_buf, prev_curtab))
2563 	return FAIL;
2564 
2565     // Now we are really going to close the window.  Disallow any autocommand
2566     // to split a window to avoid trouble.
2567     ++split_disallowed;
2568 
2569     // Free the memory used for the window and get the window that received
2570     // the screen space.
2571     wp = win_free_mem(win, &dir, NULL);
2572 
2573     // Make sure curwin isn't invalid.  It can cause severe trouble when
2574     // printing an error message.  For win_equal() curbuf needs to be valid
2575     // too.
2576     if (win == curwin)
2577     {
2578 	curwin = wp;
2579 #ifdef FEAT_QUICKFIX
2580 	if (wp->w_p_pvw || bt_quickfix(wp->w_buffer))
2581 	{
2582 	    /*
2583 	     * If the cursor goes to the preview or the quickfix window, try
2584 	     * finding another window to go to.
2585 	     */
2586 	    for (;;)
2587 	    {
2588 		if (wp->w_next == NULL)
2589 		    wp = firstwin;
2590 		else
2591 		    wp = wp->w_next;
2592 		if (wp == curwin)
2593 		    break;
2594 		if (!wp->w_p_pvw && !bt_quickfix(wp->w_buffer))
2595 		{
2596 		    curwin = wp;
2597 		    break;
2598 		}
2599 	    }
2600 	}
2601 #endif
2602 	curbuf = curwin->w_buffer;
2603 	close_curwin = TRUE;
2604 
2605 	// The cursor position may be invalid if the buffer changed after last
2606 	// using the window.
2607 	check_cursor();
2608     }
2609     if (p_ea && (*p_ead == 'b' || *p_ead == dir))
2610 	// If the frame of the closed window contains the new current window,
2611 	// only resize that frame.  Otherwise resize all windows.
2612 	win_equal(curwin, curwin->w_frame->fr_parent == win_frame, dir);
2613     else
2614 	win_comp_pos();
2615     if (close_curwin)
2616     {
2617 	win_enter_ext(wp, FALSE, TRUE, FALSE, TRUE, TRUE);
2618 	if (other_buffer)
2619 	    // careful: after this wp and win may be invalid!
2620 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2621     }
2622 
2623     --split_disallowed;
2624 
2625     /*
2626      * If last window has a status line now and we don't want one,
2627      * remove the status line.
2628      */
2629     last_status(FALSE);
2630 
2631     // After closing the help window, try restoring the window layout from
2632     // before it was opened.
2633     if (help_window)
2634 	restore_snapshot(SNAP_HELP_IDX, close_curwin);
2635 
2636 #ifdef FEAT_DIFF
2637     // If the window had 'diff' set and now there is only one window left in
2638     // the tab page with 'diff' set, and "closeoff" is in 'diffopt', then
2639     // execute ":diffoff!".
2640     if (diffopt_closeoff() && had_diffmode && curtab == prev_curtab)
2641     {
2642 	int	diffcount = 0;
2643 	win_T	*dwin;
2644 
2645 	FOR_ALL_WINDOWS(dwin)
2646 	    if (dwin->w_p_diff)
2647 		++diffcount;
2648 	if (diffcount == 1)
2649 	    do_cmdline_cmd((char_u *)"diffoff!");
2650     }
2651 #endif
2652 
2653 #if defined(FEAT_GUI)
2654     // When 'guioptions' includes 'L' or 'R' may have to remove scrollbars.
2655     if (gui.in_use && !win_hasvertsplit())
2656 	gui_init_which_components(NULL);
2657 #endif
2658 
2659     redraw_all_later(NOT_VALID);
2660     return OK;
2661 }
2662 
2663 /*
2664  * Close window "win" in tab page "tp", which is not the current tab page.
2665  * This may be the last window in that tab page and result in closing the tab,
2666  * thus "tp" may become invalid!
2667  * Caller must check if buffer is hidden and whether the tabline needs to be
2668  * updated.
2669  */
2670     void
2671 win_close_othertab(win_T *win, int free_buf, tabpage_T *tp)
2672 {
2673     win_T	*wp;
2674     int		dir;
2675     tabpage_T   *ptp = NULL;
2676     int		free_tp = FALSE;
2677 
2678     // Get here with win->w_buffer == NULL when win_close() detects the tab
2679     // page changed.
2680     if (win->w_closing || (win->w_buffer != NULL
2681 					       && win->w_buffer->b_locked > 0))
2682 	return; // window is already being closed
2683 
2684     if (win->w_buffer != NULL)
2685 	// Close the link to the buffer.
2686 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0,
2687 								 FALSE, FALSE);
2688 
2689     // Careful: Autocommands may have closed the tab page or made it the
2690     // current tab page.
2691     for (ptp = first_tabpage; ptp != NULL && ptp != tp; ptp = ptp->tp_next)
2692 	;
2693     if (ptp == NULL || tp == curtab)
2694 	return;
2695 
2696     // Autocommands may have closed the window already.
2697     for (wp = tp->tp_firstwin; wp != NULL && wp != win; wp = wp->w_next)
2698 	;
2699     if (wp == NULL)
2700 	return;
2701 
2702     // When closing the last window in a tab page remove the tab page.
2703     if (tp->tp_firstwin == tp->tp_lastwin)
2704     {
2705 	if (tp == first_tabpage)
2706 	    first_tabpage = tp->tp_next;
2707 	else
2708 	{
2709 	    for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tp;
2710 							   ptp = ptp->tp_next)
2711 		;
2712 	    if (ptp == NULL)
2713 	    {
2714 		internal_error("win_close_othertab()");
2715 		return;
2716 	    }
2717 	    ptp->tp_next = tp->tp_next;
2718 	}
2719 	free_tp = TRUE;
2720     }
2721 
2722     // Free the memory used for the window.
2723     win_free_mem(win, &dir, tp);
2724 
2725     if (free_tp)
2726 	free_tabpage(tp);
2727 }
2728 
2729 /*
2730  * Free the memory used for a window.
2731  * Returns a pointer to the window that got the freed up space.
2732  */
2733     static win_T *
2734 win_free_mem(
2735     win_T	*win,
2736     int		*dirp,		// set to 'v' or 'h' for direction if 'ea'
2737     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2738 {
2739     frame_T	*frp;
2740     win_T	*wp;
2741 
2742     // Remove the window and its frame from the tree of frames.
2743     frp = win->w_frame;
2744     wp = winframe_remove(win, dirp, tp);
2745     vim_free(frp);
2746     win_free(win, tp);
2747 
2748     // When deleting the current window of another tab page select a new
2749     // current window.
2750     if (tp != NULL && win == tp->tp_curwin)
2751 	tp->tp_curwin = wp;
2752 
2753     return wp;
2754 }
2755 
2756 #if defined(EXITFREE) || defined(PROTO)
2757     void
2758 win_free_all(void)
2759 {
2760     int		dummy;
2761 
2762     while (first_tabpage->tp_next != NULL)
2763 	tabpage_close(TRUE);
2764 
2765     if (aucmd_win != NULL)
2766     {
2767 	(void)win_free_mem(aucmd_win, &dummy, NULL);
2768 	aucmd_win = NULL;
2769     }
2770 
2771     while (firstwin != NULL)
2772 	(void)win_free_mem(firstwin, &dummy, NULL);
2773 
2774     // No window should be used after this. Set curwin to NULL to crash
2775     // instead of using freed memory.
2776     curwin = NULL;
2777 }
2778 #endif
2779 
2780 /*
2781  * Remove a window and its frame from the tree of frames.
2782  * Returns a pointer to the window that got the freed up space.
2783  */
2784     win_T *
2785 winframe_remove(
2786     win_T	*win,
2787     int		*dirp UNUSED,	// set to 'v' or 'h' for direction if 'ea'
2788     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2789 {
2790     frame_T	*frp, *frp2, *frp3;
2791     frame_T	*frp_close = win->w_frame;
2792     win_T	*wp;
2793 
2794     /*
2795      * If there is only one window there is nothing to remove.
2796      */
2797     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2798 	return NULL;
2799 
2800     /*
2801      * Remove the window from its frame.
2802      */
2803     frp2 = win_altframe(win, tp);
2804     wp = frame2win(frp2);
2805 
2806     // Remove this frame from the list of frames.
2807     frame_remove(frp_close);
2808 
2809     if (frp_close->fr_parent->fr_layout == FR_COL)
2810     {
2811 	// When 'winfixheight' is set, try to find another frame in the column
2812 	// (as close to the closed frame as possible) to distribute the height
2813 	// to.
2814 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfh)
2815 	{
2816 	    frp = frp_close->fr_prev;
2817 	    frp3 = frp_close->fr_next;
2818 	    while (frp != NULL || frp3 != NULL)
2819 	    {
2820 		if (frp != NULL)
2821 		{
2822 		    if (!frame_fixed_height(frp))
2823 		    {
2824 			frp2 = frp;
2825 			wp = frame2win(frp2);
2826 			break;
2827 		    }
2828 		    frp = frp->fr_prev;
2829 		}
2830 		if (frp3 != NULL)
2831 		{
2832 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfh)
2833 		    {
2834 			frp2 = frp3;
2835 			wp = frp3->fr_win;
2836 			break;
2837 		    }
2838 		    frp3 = frp3->fr_next;
2839 		}
2840 	    }
2841 	}
2842 	frame_new_height(frp2, frp2->fr_height + frp_close->fr_height,
2843 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2844 	*dirp = 'v';
2845     }
2846     else
2847     {
2848 	// When 'winfixwidth' is set, try to find another frame in the column
2849 	// (as close to the closed frame as possible) to distribute the width
2850 	// to.
2851 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfw)
2852 	{
2853 	    frp = frp_close->fr_prev;
2854 	    frp3 = frp_close->fr_next;
2855 	    while (frp != NULL || frp3 != NULL)
2856 	    {
2857 		if (frp != NULL)
2858 		{
2859 		    if (!frame_fixed_width(frp))
2860 		    {
2861 			frp2 = frp;
2862 			wp = frame2win(frp2);
2863 			break;
2864 		    }
2865 		    frp = frp->fr_prev;
2866 		}
2867 		if (frp3 != NULL)
2868 		{
2869 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfw)
2870 		    {
2871 			frp2 = frp3;
2872 			wp = frp3->fr_win;
2873 			break;
2874 		    }
2875 		    frp3 = frp3->fr_next;
2876 		}
2877 	    }
2878 	}
2879 	frame_new_width(frp2, frp2->fr_width + frp_close->fr_width,
2880 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2881 	*dirp = 'h';
2882     }
2883 
2884     // If rows/columns go to a window below/right its positions need to be
2885     // updated.  Can only be done after the sizes have been updated.
2886     if (frp2 == frp_close->fr_next)
2887     {
2888 	int row = win->w_winrow;
2889 	int col = win->w_wincol;
2890 
2891 	frame_comp_pos(frp2, &row, &col);
2892     }
2893 
2894     if (frp2->fr_next == NULL && frp2->fr_prev == NULL)
2895     {
2896 	// There is no other frame in this list, move its info to the parent
2897 	// and remove it.
2898 	frp2->fr_parent->fr_layout = frp2->fr_layout;
2899 	frp2->fr_parent->fr_child = frp2->fr_child;
2900 	FOR_ALL_FRAMES(frp, frp2->fr_child)
2901 	    frp->fr_parent = frp2->fr_parent;
2902 	frp2->fr_parent->fr_win = frp2->fr_win;
2903 	if (frp2->fr_win != NULL)
2904 	    frp2->fr_win->w_frame = frp2->fr_parent;
2905 	frp = frp2->fr_parent;
2906 	if (topframe->fr_child == frp2)
2907 	    topframe->fr_child = frp;
2908 	vim_free(frp2);
2909 
2910 	frp2 = frp->fr_parent;
2911 	if (frp2 != NULL && frp2->fr_layout == frp->fr_layout)
2912 	{
2913 	    // The frame above the parent has the same layout, have to merge
2914 	    // the frames into this list.
2915 	    if (frp2->fr_child == frp)
2916 		frp2->fr_child = frp->fr_child;
2917 	    frp->fr_child->fr_prev = frp->fr_prev;
2918 	    if (frp->fr_prev != NULL)
2919 		frp->fr_prev->fr_next = frp->fr_child;
2920 	    for (frp3 = frp->fr_child; ; frp3 = frp3->fr_next)
2921 	    {
2922 		frp3->fr_parent = frp2;
2923 		if (frp3->fr_next == NULL)
2924 		{
2925 		    frp3->fr_next = frp->fr_next;
2926 		    if (frp->fr_next != NULL)
2927 			frp->fr_next->fr_prev = frp3;
2928 		    break;
2929 		}
2930 	    }
2931 	    if (topframe->fr_child == frp)
2932 		topframe->fr_child = frp2;
2933 	    vim_free(frp);
2934 	}
2935     }
2936 
2937     return wp;
2938 }
2939 
2940 /*
2941  * Return a pointer to the frame that will receive the empty screen space that
2942  * is left over after "win" is closed.
2943  *
2944  * If 'splitbelow' or 'splitright' is set, the space goes above or to the left
2945  * by default.  Otherwise, the free space goes below or to the right.  The
2946  * result is that opening a window and then immediately closing it will
2947  * preserve the initial window layout.  The 'wfh' and 'wfw' settings are
2948  * respected when possible.
2949  */
2950     static frame_T *
2951 win_altframe(
2952     win_T	*win,
2953     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2954 {
2955     frame_T	*frp;
2956     frame_T	*other_fr, *target_fr;
2957 
2958     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2959 	return alt_tabpage()->tp_curwin->w_frame;
2960 
2961     frp = win->w_frame;
2962 
2963     if (frp->fr_prev == NULL)
2964 	return frp->fr_next;
2965     if (frp->fr_next == NULL)
2966 	return frp->fr_prev;
2967 
2968     // By default the next window will get the space that was abandoned by this
2969     // window
2970     target_fr = frp->fr_next;
2971     other_fr  = frp->fr_prev;
2972 
2973     // If this is part of a column of windows and 'splitbelow' is true then the
2974     // previous window will get the space.
2975     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_COL && p_sb)
2976     {
2977 	target_fr = frp->fr_prev;
2978 	other_fr  = frp->fr_next;
2979     }
2980 
2981     // If this is part of a row of windows, and 'splitright' is true then the
2982     // previous window will get the space.
2983     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW && p_spr)
2984     {
2985 	target_fr = frp->fr_prev;
2986 	other_fr  = frp->fr_next;
2987     }
2988 
2989     // If 'wfh' or 'wfw' is set for the target and not for the alternate
2990     // window, reverse the selection.
2991     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW)
2992     {
2993 	if (frame_fixed_width(target_fr) && !frame_fixed_width(other_fr))
2994 	    target_fr = other_fr;
2995     }
2996     else
2997     {
2998 	if (frame_fixed_height(target_fr) && !frame_fixed_height(other_fr))
2999 	    target_fr = other_fr;
3000     }
3001 
3002     return target_fr;
3003 }
3004 
3005 /*
3006  * Return the tabpage that will be used if the current one is closed.
3007  */
3008     static tabpage_T *
3009 alt_tabpage(void)
3010 {
3011     tabpage_T	*tp;
3012 
3013     // Use the next tab page if possible.
3014     if (curtab->tp_next != NULL)
3015 	return curtab->tp_next;
3016 
3017     // Find the last but one tab page.
3018     for (tp = first_tabpage; tp->tp_next != curtab; tp = tp->tp_next)
3019 	;
3020     return tp;
3021 }
3022 
3023 /*
3024  * Find the left-upper window in frame "frp".
3025  */
3026     static win_T *
3027 frame2win(frame_T *frp)
3028 {
3029     while (frp->fr_win == NULL)
3030 	frp = frp->fr_child;
3031     return frp->fr_win;
3032 }
3033 
3034 /*
3035  * Return TRUE if frame "frp" contains window "wp".
3036  */
3037     static int
3038 frame_has_win(frame_T *frp, win_T *wp)
3039 {
3040     frame_T	*p;
3041 
3042     if (frp->fr_layout == FR_LEAF)
3043 	return frp->fr_win == wp;
3044 
3045     FOR_ALL_FRAMES(p, frp->fr_child)
3046 	if (frame_has_win(p, wp))
3047 	    return TRUE;
3048     return FALSE;
3049 }
3050 
3051 /*
3052  * Set a new height for a frame.  Recursively sets the height for contained
3053  * frames and windows.  Caller must take care of positions.
3054  */
3055     static void
3056 frame_new_height(
3057     frame_T	*topfrp,
3058     int		height,
3059     int		topfirst,	// resize topmost contained frame first
3060     int		wfh)		// obey 'winfixheight' when there is a choice;
3061 				// may cause the height not to be set
3062 {
3063     frame_T	*frp;
3064     int		extra_lines;
3065     int		h;
3066 
3067     if (topfrp->fr_win != NULL)
3068     {
3069 	// Simple case: just one window.
3070 	win_new_height(topfrp->fr_win,
3071 				    height - topfrp->fr_win->w_status_height
3072 					      - WINBAR_HEIGHT(topfrp->fr_win));
3073     }
3074     else if (topfrp->fr_layout == FR_ROW)
3075     {
3076 	do
3077 	{
3078 	    // All frames in this row get the same new height.
3079 	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
3080 	    {
3081 		frame_new_height(frp, height, topfirst, wfh);
3082 		if (frp->fr_height > height)
3083 		{
3084 		    // Could not fit the windows, make the whole row higher.
3085 		    height = frp->fr_height;
3086 		    break;
3087 		}
3088 	    }
3089 	}
3090 	while (frp != NULL);
3091     }
3092     else    // fr_layout == FR_COL
3093     {
3094 	// Complicated case: Resize a column of frames.  Resize the bottom
3095 	// frame first, frames above that when needed.
3096 
3097 	frp = topfrp->fr_child;
3098 	if (wfh)
3099 	    // Advance past frames with one window with 'wfh' set.
3100 	    while (frame_fixed_height(frp))
3101 	    {
3102 		frp = frp->fr_next;
3103 		if (frp == NULL)
3104 		    return;	    // no frame without 'wfh', give up
3105 	    }
3106 	if (!topfirst)
3107 	{
3108 	    // Find the bottom frame of this column
3109 	    while (frp->fr_next != NULL)
3110 		frp = frp->fr_next;
3111 	    if (wfh)
3112 		// Advance back for frames with one window with 'wfh' set.
3113 		while (frame_fixed_height(frp))
3114 		    frp = frp->fr_prev;
3115 	}
3116 
3117 	extra_lines = height - topfrp->fr_height;
3118 	if (extra_lines < 0)
3119 	{
3120 	    // reduce height of contained frames, bottom or top frame first
3121 	    while (frp != NULL)
3122 	    {
3123 		h = frame_minheight(frp, NULL);
3124 		if (frp->fr_height + extra_lines < h)
3125 		{
3126 		    extra_lines += frp->fr_height - h;
3127 		    frame_new_height(frp, h, topfirst, wfh);
3128 		}
3129 		else
3130 		{
3131 		    frame_new_height(frp, frp->fr_height + extra_lines,
3132 							       topfirst, wfh);
3133 		    break;
3134 		}
3135 		if (topfirst)
3136 		{
3137 		    do
3138 			frp = frp->fr_next;
3139 		    while (wfh && frp != NULL && frame_fixed_height(frp));
3140 		}
3141 		else
3142 		{
3143 		    do
3144 			frp = frp->fr_prev;
3145 		    while (wfh && frp != NULL && frame_fixed_height(frp));
3146 		}
3147 		// Increase "height" if we could not reduce enough frames.
3148 		if (frp == NULL)
3149 		    height -= extra_lines;
3150 	    }
3151 	}
3152 	else if (extra_lines > 0)
3153 	{
3154 	    // increase height of bottom or top frame
3155 	    frame_new_height(frp, frp->fr_height + extra_lines, topfirst, wfh);
3156 	}
3157     }
3158     topfrp->fr_height = height;
3159 }
3160 
3161 /*
3162  * Return TRUE if height of frame "frp" should not be changed because of
3163  * the 'winfixheight' option.
3164  */
3165     static int
3166 frame_fixed_height(frame_T *frp)
3167 {
3168     // frame with one window: fixed height if 'winfixheight' set.
3169     if (frp->fr_win != NULL)
3170 	return frp->fr_win->w_p_wfh;
3171 
3172     if (frp->fr_layout == FR_ROW)
3173     {
3174 	// The frame is fixed height if one of the frames in the row is fixed
3175 	// height.
3176 	FOR_ALL_FRAMES(frp, frp->fr_child)
3177 	    if (frame_fixed_height(frp))
3178 		return TRUE;
3179 	return FALSE;
3180     }
3181 
3182     // frp->fr_layout == FR_COL: The frame is fixed height if all of the
3183     // frames in the row are fixed height.
3184     FOR_ALL_FRAMES(frp, frp->fr_child)
3185 	if (!frame_fixed_height(frp))
3186 	    return FALSE;
3187     return TRUE;
3188 }
3189 
3190 /*
3191  * Return TRUE if width of frame "frp" should not be changed because of
3192  * the 'winfixwidth' option.
3193  */
3194     static int
3195 frame_fixed_width(frame_T *frp)
3196 {
3197     // frame with one window: fixed width if 'winfixwidth' set.
3198     if (frp->fr_win != NULL)
3199 	return frp->fr_win->w_p_wfw;
3200 
3201     if (frp->fr_layout == FR_COL)
3202     {
3203 	// The frame is fixed width if one of the frames in the row is fixed
3204 	// width.
3205 	FOR_ALL_FRAMES(frp, frp->fr_child)
3206 	    if (frame_fixed_width(frp))
3207 		return TRUE;
3208 	return FALSE;
3209     }
3210 
3211     // frp->fr_layout == FR_ROW: The frame is fixed width if all of the
3212     // frames in the row are fixed width.
3213     FOR_ALL_FRAMES(frp, frp->fr_child)
3214 	if (!frame_fixed_width(frp))
3215 	    return FALSE;
3216     return TRUE;
3217 }
3218 
3219 /*
3220  * Add a status line to windows at the bottom of "frp".
3221  * Note: Does not check if there is room!
3222  */
3223     static void
3224 frame_add_statusline(frame_T *frp)
3225 {
3226     win_T	*wp;
3227 
3228     if (frp->fr_layout == FR_LEAF)
3229     {
3230 	wp = frp->fr_win;
3231 	if (wp->w_status_height == 0)
3232 	{
3233 	    if (wp->w_height > 0)	// don't make it negative
3234 		--wp->w_height;
3235 	    wp->w_status_height = STATUS_HEIGHT;
3236 	}
3237     }
3238     else if (frp->fr_layout == FR_ROW)
3239     {
3240 	// Handle all the frames in the row.
3241 	FOR_ALL_FRAMES(frp, frp->fr_child)
3242 	    frame_add_statusline(frp);
3243     }
3244     else // frp->fr_layout == FR_COL
3245     {
3246 	// Only need to handle the last frame in the column.
3247 	for (frp = frp->fr_child; frp->fr_next != NULL; frp = frp->fr_next)
3248 	    ;
3249 	frame_add_statusline(frp);
3250     }
3251 }
3252 
3253 /*
3254  * Set width of a frame.  Handles recursively going through contained frames.
3255  * May remove separator line for windows at the right side (for win_close()).
3256  */
3257     static void
3258 frame_new_width(
3259     frame_T	*topfrp,
3260     int		width,
3261     int		leftfirst,	// resize leftmost contained frame first
3262     int		wfw)		// obey 'winfixwidth' when there is a choice;
3263 				// may cause the width not to be set
3264 {
3265     frame_T	*frp;
3266     int		extra_cols;
3267     int		w;
3268     win_T	*wp;
3269 
3270     if (topfrp->fr_layout == FR_LEAF)
3271     {
3272 	// Simple case: just one window.
3273 	wp = topfrp->fr_win;
3274 	// Find out if there are any windows right of this one.
3275 	for (frp = topfrp; frp->fr_parent != NULL; frp = frp->fr_parent)
3276 	    if (frp->fr_parent->fr_layout == FR_ROW && frp->fr_next != NULL)
3277 		break;
3278 	if (frp->fr_parent == NULL)
3279 	    wp->w_vsep_width = 0;
3280 	win_new_width(wp, width - wp->w_vsep_width);
3281     }
3282     else if (topfrp->fr_layout == FR_COL)
3283     {
3284 	do
3285 	{
3286 	    // All frames in this column get the same new width.
3287 	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
3288 	    {
3289 		frame_new_width(frp, width, leftfirst, wfw);
3290 		if (frp->fr_width > width)
3291 		{
3292 		    // Could not fit the windows, make whole column wider.
3293 		    width = frp->fr_width;
3294 		    break;
3295 		}
3296 	    }
3297 	} while (frp != NULL);
3298     }
3299     else    // fr_layout == FR_ROW
3300     {
3301 	// Complicated case: Resize a row of frames.  Resize the rightmost
3302 	// frame first, frames left of it when needed.
3303 
3304 	frp = topfrp->fr_child;
3305 	if (wfw)
3306 	    // Advance past frames with one window with 'wfw' set.
3307 	    while (frame_fixed_width(frp))
3308 	    {
3309 		frp = frp->fr_next;
3310 		if (frp == NULL)
3311 		    return;	    // no frame without 'wfw', give up
3312 	    }
3313 	if (!leftfirst)
3314 	{
3315 	    // Find the rightmost frame of this row
3316 	    while (frp->fr_next != NULL)
3317 		frp = frp->fr_next;
3318 	    if (wfw)
3319 		// Advance back for frames with one window with 'wfw' set.
3320 		while (frame_fixed_width(frp))
3321 		    frp = frp->fr_prev;
3322 	}
3323 
3324 	extra_cols = width - topfrp->fr_width;
3325 	if (extra_cols < 0)
3326 	{
3327 	    // reduce frame width, rightmost frame first
3328 	    while (frp != NULL)
3329 	    {
3330 		w = frame_minwidth(frp, NULL);
3331 		if (frp->fr_width + extra_cols < w)
3332 		{
3333 		    extra_cols += frp->fr_width - w;
3334 		    frame_new_width(frp, w, leftfirst, wfw);
3335 		}
3336 		else
3337 		{
3338 		    frame_new_width(frp, frp->fr_width + extra_cols,
3339 							      leftfirst, wfw);
3340 		    break;
3341 		}
3342 		if (leftfirst)
3343 		{
3344 		    do
3345 			frp = frp->fr_next;
3346 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3347 		}
3348 		else
3349 		{
3350 		    do
3351 			frp = frp->fr_prev;
3352 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3353 		}
3354 		// Increase "width" if we could not reduce enough frames.
3355 		if (frp == NULL)
3356 		    width -= extra_cols;
3357 	    }
3358 	}
3359 	else if (extra_cols > 0)
3360 	{
3361 	    // increase width of rightmost frame
3362 	    frame_new_width(frp, frp->fr_width + extra_cols, leftfirst, wfw);
3363 	}
3364     }
3365     topfrp->fr_width = width;
3366 }
3367 
3368 /*
3369  * Add the vertical separator to windows at the right side of "frp".
3370  * Note: Does not check if there is room!
3371  */
3372     static void
3373 frame_add_vsep(frame_T *frp)
3374 {
3375     win_T	*wp;
3376 
3377     if (frp->fr_layout == FR_LEAF)
3378     {
3379 	wp = frp->fr_win;
3380 	if (wp->w_vsep_width == 0)
3381 	{
3382 	    if (wp->w_width > 0)	// don't make it negative
3383 		--wp->w_width;
3384 	    wp->w_vsep_width = 1;
3385 	}
3386     }
3387     else if (frp->fr_layout == FR_COL)
3388     {
3389 	// Handle all the frames in the column.
3390 	FOR_ALL_FRAMES(frp, frp->fr_child)
3391 	    frame_add_vsep(frp);
3392     }
3393     else // frp->fr_layout == FR_ROW
3394     {
3395 	// Only need to handle the last frame in the row.
3396 	frp = frp->fr_child;
3397 	while (frp->fr_next != NULL)
3398 	    frp = frp->fr_next;
3399 	frame_add_vsep(frp);
3400     }
3401 }
3402 
3403 /*
3404  * Set frame width from the window it contains.
3405  */
3406     static void
3407 frame_fix_width(win_T *wp)
3408 {
3409     wp->w_frame->fr_width = wp->w_width + wp->w_vsep_width;
3410 }
3411 
3412 /*
3413  * Set frame height from the window it contains.
3414  */
3415     static void
3416 frame_fix_height(win_T *wp)
3417 {
3418     wp->w_frame->fr_height = VISIBLE_HEIGHT(wp) + wp->w_status_height;
3419 }
3420 
3421 /*
3422  * Compute the minimal height for frame "topfrp".
3423  * Uses the 'winminheight' option.
3424  * When "next_curwin" isn't NULL, use p_wh for this window.
3425  * When "next_curwin" is NOWIN, don't use at least one line for the current
3426  * window.
3427  */
3428     static int
3429 frame_minheight(frame_T *topfrp, win_T *next_curwin)
3430 {
3431     frame_T	*frp;
3432     int		m;
3433     int		n;
3434 
3435     if (topfrp->fr_win != NULL)
3436     {
3437 	if (topfrp->fr_win == next_curwin)
3438 	    m = p_wh + topfrp->fr_win->w_status_height;
3439 	else
3440 	{
3441 	    // window: minimal height of the window plus status line
3442 	    m = p_wmh + topfrp->fr_win->w_status_height;
3443 	    if (topfrp->fr_win == curwin && next_curwin == NULL)
3444 	    {
3445 		// Current window is minimal one line high and WinBar is
3446 		// visible.
3447 		if (p_wmh == 0)
3448 		    ++m;
3449 		m += WINBAR_HEIGHT(curwin);
3450 	    }
3451 	}
3452     }
3453     else if (topfrp->fr_layout == FR_ROW)
3454     {
3455 	// get the minimal height from each frame in this row
3456 	m = 0;
3457 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3458 	{
3459 	    n = frame_minheight(frp, next_curwin);
3460 	    if (n > m)
3461 		m = n;
3462 	}
3463     }
3464     else
3465     {
3466 	// Add up the minimal heights for all frames in this column.
3467 	m = 0;
3468 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3469 	    m += frame_minheight(frp, next_curwin);
3470     }
3471 
3472     return m;
3473 }
3474 
3475 /*
3476  * Compute the minimal width for frame "topfrp".
3477  * When "next_curwin" isn't NULL, use p_wiw for this window.
3478  * When "next_curwin" is NOWIN, don't use at least one column for the current
3479  * window.
3480  */
3481     static int
3482 frame_minwidth(
3483     frame_T	*topfrp,
3484     win_T	*next_curwin)	// use p_wh and p_wiw for next_curwin
3485 {
3486     frame_T	*frp;
3487     int		m, n;
3488 
3489     if (topfrp->fr_win != NULL)
3490     {
3491 	if (topfrp->fr_win == next_curwin)
3492 	    m = p_wiw + topfrp->fr_win->w_vsep_width;
3493 	else
3494 	{
3495 	    // window: minimal width of the window plus separator column
3496 	    m = p_wmw + topfrp->fr_win->w_vsep_width;
3497 	    // Current window is minimal one column wide
3498 	    if (p_wmw == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3499 		++m;
3500 	}
3501     }
3502     else if (topfrp->fr_layout == FR_COL)
3503     {
3504 	// get the minimal width from each frame in this column
3505 	m = 0;
3506 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3507 	{
3508 	    n = frame_minwidth(frp, next_curwin);
3509 	    if (n > m)
3510 		m = n;
3511 	}
3512     }
3513     else
3514     {
3515 	// Add up the minimal widths for all frames in this row.
3516 	m = 0;
3517 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3518 	    m += frame_minwidth(frp, next_curwin);
3519     }
3520 
3521     return m;
3522 }
3523 
3524 
3525 /*
3526  * Try to close all windows except current one.
3527  * Buffers in the other windows become hidden if 'hidden' is set, or '!' is
3528  * used and the buffer was modified.
3529  *
3530  * Used by ":bdel" and ":only".
3531  */
3532     void
3533 close_others(
3534     int		message,
3535     int		forceit)	    // always hide all other windows
3536 {
3537     win_T	*wp;
3538     win_T	*nextwp;
3539     int		r;
3540 
3541     if (one_window())
3542     {
3543 	if (message && !autocmd_busy)
3544 	    msg(_(m_onlyone));
3545 	return;
3546     }
3547 
3548     // Be very careful here: autocommands may change the window layout.
3549     for (wp = firstwin; win_valid(wp); wp = nextwp)
3550     {
3551 	nextwp = wp->w_next;
3552 	if (wp != curwin)		// don't close current window
3553 	{
3554 
3555 	    // Check if it's allowed to abandon this window
3556 	    r = can_abandon(wp->w_buffer, forceit);
3557 	    if (!win_valid(wp))		// autocommands messed wp up
3558 	    {
3559 		nextwp = firstwin;
3560 		continue;
3561 	    }
3562 	    if (!r)
3563 	    {
3564 #if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
3565 		if (message && (p_confirm || cmdmod.confirm) && p_write)
3566 		{
3567 		    dialog_changed(wp->w_buffer, FALSE);
3568 		    if (!win_valid(wp))		// autocommands messed wp up
3569 		    {
3570 			nextwp = firstwin;
3571 			continue;
3572 		    }
3573 		}
3574 		if (bufIsChanged(wp->w_buffer))
3575 #endif
3576 		    continue;
3577 	    }
3578 	    win_close(wp, !buf_hide(wp->w_buffer)
3579 					       && !bufIsChanged(wp->w_buffer));
3580 	}
3581     }
3582 
3583     if (message && !ONE_WINDOW)
3584 	emsg(_("E445: Other window contains changes"));
3585 }
3586 
3587     static void
3588 win_init_empty(win_T *wp)
3589 {
3590     redraw_win_later(wp, NOT_VALID);
3591     wp->w_lines_valid = 0;
3592     wp->w_cursor.lnum = 1;
3593     wp->w_curswant = wp->w_cursor.col = 0;
3594     wp->w_cursor.coladd = 0;
3595     wp->w_pcmark.lnum = 1;	// pcmark not cleared but set to line 1
3596     wp->w_pcmark.col = 0;
3597     wp->w_prev_pcmark.lnum = 0;
3598     wp->w_prev_pcmark.col = 0;
3599     wp->w_topline = 1;
3600 #ifdef FEAT_DIFF
3601     wp->w_topfill = 0;
3602 #endif
3603     wp->w_botline = 2;
3604 #if defined(FEAT_SYN_HL) || defined(FEAT_SPELL)
3605     wp->w_s = &wp->w_buffer->b_s;
3606 #endif
3607 }
3608 
3609 /*
3610  * Init the current window "curwin".
3611  * Called when a new file is being edited.
3612  */
3613     void
3614 curwin_init(void)
3615 {
3616     win_init_empty(curwin);
3617 }
3618 
3619 /*
3620  * Allocate the first window and put an empty buffer in it.
3621  * Called from main().
3622  * Return FAIL when something goes wrong (out of memory).
3623  */
3624     int
3625 win_alloc_first(void)
3626 {
3627     if (win_alloc_firstwin(NULL) == FAIL)
3628 	return FAIL;
3629 
3630     first_tabpage = alloc_tabpage();
3631     if (first_tabpage == NULL)
3632 	return FAIL;
3633     first_tabpage->tp_topframe = topframe;
3634     curtab = first_tabpage;
3635     curtab->tp_firstwin = firstwin;
3636     curtab->tp_lastwin = lastwin;
3637     curtab->tp_curwin = curwin;
3638 
3639     return OK;
3640 }
3641 
3642 /*
3643  * Allocate and init a window that is not a regular window.
3644  * This can only be done after the first window is fully initialized, thus it
3645  * can't be in win_alloc_first().
3646  */
3647     win_T *
3648 win_alloc_popup_win(void)
3649 {
3650     win_T *wp;
3651 
3652     wp = win_alloc(NULL, TRUE);
3653     if (wp != NULL)
3654     {
3655 	// We need to initialize options with something, using the current
3656 	// window makes most sense.
3657 	win_init_some(wp, curwin);
3658 
3659 	RESET_BINDING(wp);
3660 	new_frame(wp);
3661     }
3662     return wp;
3663 }
3664 
3665 /*
3666  * Initialize window "wp" to display buffer "buf".
3667  */
3668     void
3669 win_init_popup_win(win_T *wp, buf_T *buf)
3670 {
3671     wp->w_buffer = buf;
3672     ++buf->b_nwindows;
3673     win_init_empty(wp); // set cursor and topline to safe values
3674 
3675     // Make sure w_localdir and globaldir are NULL to avoid a chdir() in
3676     // win_enter_ext().
3677     VIM_CLEAR(wp->w_localdir);
3678 }
3679 
3680 /*
3681  * Allocate the first window or the first window in a new tab page.
3682  * When "oldwin" is NULL create an empty buffer for it.
3683  * When "oldwin" is not NULL copy info from it to the new window.
3684  * Return FAIL when something goes wrong (out of memory).
3685  */
3686     static int
3687 win_alloc_firstwin(win_T *oldwin)
3688 {
3689     curwin = win_alloc(NULL, FALSE);
3690     if (oldwin == NULL)
3691     {
3692 	// Very first window, need to create an empty buffer for it and
3693 	// initialize from scratch.
3694 	curbuf = buflist_new(NULL, NULL, 1L, BLN_LISTED);
3695 	if (curwin == NULL || curbuf == NULL)
3696 	    return FAIL;
3697 	curwin->w_buffer = curbuf;
3698 #ifdef FEAT_SYN_HL
3699 	curwin->w_s = &(curbuf->b_s);
3700 #endif
3701 	curbuf->b_nwindows = 1;	// there is one window
3702 	curwin->w_alist = &global_alist;
3703 	curwin_init();		// init current window
3704     }
3705     else
3706     {
3707 	// First window in new tab page, initialize it from "oldwin".
3708 	win_init(curwin, oldwin, 0);
3709 
3710 	// We don't want cursor- and scroll-binding in the first window.
3711 	RESET_BINDING(curwin);
3712     }
3713 
3714     new_frame(curwin);
3715     if (curwin->w_frame == NULL)
3716 	return FAIL;
3717     topframe = curwin->w_frame;
3718     topframe->fr_width = Columns;
3719     topframe->fr_height = Rows - p_ch;
3720 
3721     return OK;
3722 }
3723 
3724 /*
3725  * Create a frame for window "wp".
3726  */
3727     static void
3728 new_frame(win_T *wp)
3729 {
3730     frame_T *frp = ALLOC_CLEAR_ONE(frame_T);
3731 
3732     wp->w_frame = frp;
3733     if (frp != NULL)
3734     {
3735 	frp->fr_layout = FR_LEAF;
3736 	frp->fr_win = wp;
3737     }
3738 }
3739 
3740 /*
3741  * Initialize the window and frame size to the maximum.
3742  */
3743     void
3744 win_init_size(void)
3745 {
3746     firstwin->w_height = ROWS_AVAIL;
3747     topframe->fr_height = ROWS_AVAIL;
3748     firstwin->w_width = Columns;
3749     topframe->fr_width = Columns;
3750 }
3751 
3752 /*
3753  * Allocate a new tabpage_T and init the values.
3754  * Returns NULL when out of memory.
3755  */
3756     static tabpage_T *
3757 alloc_tabpage(void)
3758 {
3759     tabpage_T	*tp;
3760 # ifdef FEAT_GUI
3761     int		i;
3762 # endif
3763 
3764 
3765     tp = ALLOC_CLEAR_ONE(tabpage_T);
3766     if (tp == NULL)
3767 	return NULL;
3768 
3769 # ifdef FEAT_EVAL
3770     // init t: variables
3771     tp->tp_vars = dict_alloc();
3772     if (tp->tp_vars == NULL)
3773     {
3774 	vim_free(tp);
3775 	return NULL;
3776     }
3777     init_var_dict(tp->tp_vars, &tp->tp_winvar, VAR_SCOPE);
3778 # endif
3779 
3780 # ifdef FEAT_GUI
3781     for (i = 0; i < 3; i++)
3782 	tp->tp_prev_which_scrollbars[i] = -1;
3783 # endif
3784 # ifdef FEAT_DIFF
3785     tp->tp_diff_invalid = TRUE;
3786 # endif
3787     tp->tp_ch_used = p_ch;
3788 
3789     return tp;
3790 }
3791 
3792     void
3793 free_tabpage(tabpage_T *tp)
3794 {
3795     int idx;
3796 
3797 # ifdef FEAT_DIFF
3798     diff_clear(tp);
3799 # endif
3800 # ifdef FEAT_PROP_POPUP
3801     while (tp->tp_first_popupwin != NULL)
3802 	popup_close_tabpage(tp, tp->tp_first_popupwin->w_id, TRUE);
3803 #endif
3804     for (idx = 0; idx < SNAP_COUNT; ++idx)
3805 	clear_snapshot(tp, idx);
3806 #ifdef FEAT_EVAL
3807     vars_clear(&tp->tp_vars->dv_hashtab);	// free all t: variables
3808     hash_init(&tp->tp_vars->dv_hashtab);
3809     unref_var_dict(tp->tp_vars);
3810 #endif
3811 
3812     vim_free(tp->tp_localdir);
3813     vim_free(tp->tp_prevdir);
3814 
3815 #ifdef FEAT_PYTHON
3816     python_tabpage_free(tp);
3817 #endif
3818 
3819 #ifdef FEAT_PYTHON3
3820     python3_tabpage_free(tp);
3821 #endif
3822 
3823     vim_free(tp);
3824 }
3825 
3826 /*
3827  * Create a new Tab page with one window.
3828  * It will edit the current buffer, like after ":split".
3829  * When "after" is 0 put it just after the current Tab page.
3830  * Otherwise put it just before tab page "after".
3831  * Return FAIL or OK.
3832  */
3833     int
3834 win_new_tabpage(int after)
3835 {
3836     tabpage_T	*tp = curtab;
3837     tabpage_T	*newtp;
3838     int		n;
3839 
3840     newtp = alloc_tabpage();
3841     if (newtp == NULL)
3842 	return FAIL;
3843 
3844     // Remember the current windows in this Tab page.
3845     if (leave_tabpage(curbuf, TRUE) == FAIL)
3846     {
3847 	vim_free(newtp);
3848 	return FAIL;
3849     }
3850     curtab = newtp;
3851 
3852     newtp->tp_localdir = (tp->tp_localdir == NULL)
3853 				    ? NULL : vim_strsave(tp->tp_localdir);
3854     // Create a new empty window.
3855     if (win_alloc_firstwin(tp->tp_curwin) == OK)
3856     {
3857 	// Make the new Tab page the new topframe.
3858 	if (after == 1)
3859 	{
3860 	    // New tab page becomes the first one.
3861 	    newtp->tp_next = first_tabpage;
3862 	    first_tabpage = newtp;
3863 	}
3864 	else
3865 	{
3866 	    if (after > 0)
3867 	    {
3868 		// Put new tab page before tab page "after".
3869 		n = 2;
3870 		for (tp = first_tabpage; tp->tp_next != NULL
3871 					       && n < after; tp = tp->tp_next)
3872 		    ++n;
3873 	    }
3874 	    newtp->tp_next = tp->tp_next;
3875 	    tp->tp_next = newtp;
3876 	}
3877 	newtp->tp_firstwin = newtp->tp_lastwin = newtp->tp_curwin = curwin;
3878 
3879 	win_init_size();
3880 	firstwin->w_winrow = tabline_height();
3881 	win_comp_scroll(curwin);
3882 
3883 	newtp->tp_topframe = topframe;
3884 	last_status(FALSE);
3885 
3886 #if defined(FEAT_GUI)
3887 	// When 'guioptions' includes 'L' or 'R' may have to remove or add
3888 	// scrollbars.  Have to update them anyway.
3889 	gui_may_update_scrollbars();
3890 #endif
3891 #ifdef FEAT_JOB_CHANNEL
3892 	entering_window(curwin);
3893 #endif
3894 
3895 	redraw_all_later(NOT_VALID);
3896 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
3897 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
3898 	apply_autocmds(EVENT_TABNEW, NULL, NULL, FALSE, curbuf);
3899 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3900 	return OK;
3901     }
3902 
3903     // Failed, get back the previous Tab page
3904     enter_tabpage(curtab, curbuf, TRUE, TRUE);
3905     return FAIL;
3906 }
3907 
3908 /*
3909  * Open a new tab page if ":tab cmd" was used.  It will edit the same buffer,
3910  * like with ":split".
3911  * Returns OK if a new tab page was created, FAIL otherwise.
3912  */
3913     static int
3914 may_open_tabpage(void)
3915 {
3916     int		n = (cmdmod.tab == 0) ? postponed_split_tab : cmdmod.tab;
3917 
3918     if (n != 0)
3919     {
3920 	cmdmod.tab = 0;	    // reset it to avoid doing it twice
3921 	postponed_split_tab = 0;
3922 	return win_new_tabpage(n);
3923     }
3924     return FAIL;
3925 }
3926 
3927 /*
3928  * Create up to "maxcount" tabpages with empty windows.
3929  * Returns the number of resulting tab pages.
3930  */
3931     int
3932 make_tabpages(int maxcount)
3933 {
3934     int		count = maxcount;
3935     int		todo;
3936 
3937     // Limit to 'tabpagemax' tabs.
3938     if (count > p_tpm)
3939 	count = p_tpm;
3940 
3941     /*
3942      * Don't execute autocommands while creating the tab pages.  Must do that
3943      * when putting the buffers in the windows.
3944      */
3945     block_autocmds();
3946 
3947     for (todo = count - 1; todo > 0; --todo)
3948 	if (win_new_tabpage(0) == FAIL)
3949 	    break;
3950 
3951     unblock_autocmds();
3952 
3953     // return actual number of tab pages
3954     return (count - todo);
3955 }
3956 
3957 /*
3958  * Return TRUE when "tpc" points to a valid tab page.
3959  */
3960     int
3961 valid_tabpage(tabpage_T *tpc)
3962 {
3963     tabpage_T	*tp;
3964 
3965     FOR_ALL_TABPAGES(tp)
3966 	if (tp == tpc)
3967 	    return TRUE;
3968     return FALSE;
3969 }
3970 
3971 /*
3972  * Return TRUE when "tpc" points to a valid tab page and at least one window is
3973  * valid.
3974  */
3975     int
3976 valid_tabpage_win(tabpage_T *tpc)
3977 {
3978     tabpage_T	*tp;
3979     win_T	*wp;
3980 
3981     FOR_ALL_TABPAGES(tp)
3982     {
3983 	if (tp == tpc)
3984 	{
3985 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
3986 	    {
3987 		if (win_valid_any_tab(wp))
3988 		    return TRUE;
3989 	    }
3990 	    return FALSE;
3991 	}
3992     }
3993     // shouldn't happen
3994     return FALSE;
3995 }
3996 
3997 /*
3998  * Close tabpage "tab", assuming it has no windows in it.
3999  * There must be another tabpage or this will crash.
4000  */
4001     void
4002 close_tabpage(tabpage_T *tab)
4003 {
4004     tabpage_T	*ptp;
4005 
4006     if (tab == first_tabpage)
4007     {
4008 	first_tabpage = tab->tp_next;
4009 	ptp = first_tabpage;
4010     }
4011     else
4012     {
4013 	for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tab;
4014 							    ptp = ptp->tp_next)
4015 	    ;
4016 	assert(ptp != NULL);
4017 	ptp->tp_next = tab->tp_next;
4018     }
4019 
4020     goto_tabpage_tp(ptp, FALSE, FALSE);
4021     free_tabpage(tab);
4022 }
4023 
4024 /*
4025  * Find tab page "n" (first one is 1).  Returns NULL when not found.
4026  */
4027     tabpage_T *
4028 find_tabpage(int n)
4029 {
4030     tabpage_T	*tp;
4031     int		i = 1;
4032 
4033     if (n == 0)
4034 	return curtab;
4035 
4036     for (tp = first_tabpage; tp != NULL && i != n; tp = tp->tp_next)
4037 	++i;
4038     return tp;
4039 }
4040 
4041 /*
4042  * Get index of tab page "tp".  First one has index 1.
4043  * When not found returns number of tab pages plus one.
4044  */
4045     int
4046 tabpage_index(tabpage_T *ftp)
4047 {
4048     int		i = 1;
4049     tabpage_T	*tp;
4050 
4051     for (tp = first_tabpage; tp != NULL && tp != ftp; tp = tp->tp_next)
4052 	++i;
4053     return i;
4054 }
4055 
4056 /*
4057  * Prepare for leaving the current tab page.
4058  * When autocommands change "curtab" we don't leave the tab page and return
4059  * FAIL.
4060  * Careful: When OK is returned need to get a new tab page very very soon!
4061  */
4062     static int
4063 leave_tabpage(
4064     buf_T	*new_curbuf UNUSED,    // what is going to be the new curbuf,
4065 				       // NULL if unknown
4066     int		trigger_leave_autocmds UNUSED)
4067 {
4068     tabpage_T	*tp = curtab;
4069 
4070 #ifdef FEAT_JOB_CHANNEL
4071     leaving_window(curwin);
4072 #endif
4073     reset_VIsual_and_resel();	// stop Visual mode
4074     if (trigger_leave_autocmds)
4075     {
4076 	if (new_curbuf != curbuf)
4077 	{
4078 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4079 	    if (curtab != tp)
4080 		return FAIL;
4081 	}
4082 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4083 	if (curtab != tp)
4084 	    return FAIL;
4085 	apply_autocmds(EVENT_TABLEAVE, NULL, NULL, FALSE, curbuf);
4086 	if (curtab != tp)
4087 	    return FAIL;
4088     }
4089 #if defined(FEAT_GUI)
4090     // Remove the scrollbars.  They may be added back later.
4091     if (gui.in_use)
4092 	gui_remove_scrollbars();
4093 #endif
4094     tp->tp_curwin = curwin;
4095     tp->tp_prevwin = prevwin;
4096     tp->tp_firstwin = firstwin;
4097     tp->tp_lastwin = lastwin;
4098     tp->tp_old_Rows = Rows;
4099     tp->tp_old_Columns = Columns;
4100     firstwin = NULL;
4101     lastwin = NULL;
4102     return OK;
4103 }
4104 
4105 /*
4106  * Start using tab page "tp".
4107  * Only to be used after leave_tabpage() or freeing the current tab page.
4108  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4109  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4110  */
4111     static void
4112 enter_tabpage(
4113     tabpage_T	*tp,
4114     buf_T	*old_curbuf UNUSED,
4115     int		trigger_enter_autocmds,
4116     int		trigger_leave_autocmds)
4117 {
4118     int		row;
4119     int		old_off = tp->tp_firstwin->w_winrow;
4120     win_T	*next_prevwin = tp->tp_prevwin;
4121 
4122     curtab = tp;
4123     firstwin = tp->tp_firstwin;
4124     lastwin = tp->tp_lastwin;
4125     topframe = tp->tp_topframe;
4126 
4127     // We would like doing the TabEnter event first, but we don't have a
4128     // valid current window yet, which may break some commands.
4129     // This triggers autocommands, thus may make "tp" invalid.
4130     win_enter_ext(tp->tp_curwin, FALSE, TRUE, FALSE,
4131 			      trigger_enter_autocmds, trigger_leave_autocmds);
4132     prevwin = next_prevwin;
4133 
4134     last_status(FALSE);		// status line may appear or disappear
4135     row = win_comp_pos();	// recompute w_winrow for all windows
4136 #ifdef FEAT_DIFF
4137     diff_need_scrollbind = TRUE;
4138 #endif
4139 
4140     // The tabpage line may have appeared or disappeared, may need to resize
4141     // the frames for that.  When the Vim window was resized need to update
4142     // frame sizes too.  Use the stored value of p_ch, so that it can be
4143     // different for each tab page.
4144     if (p_ch != curtab->tp_ch_used)
4145 	clear_cmdline = TRUE;
4146     p_ch = curtab->tp_ch_used;
4147 
4148     // When cmdheight is changed in a tab page with '<C-w>-', cmdline_row is
4149     // changed but p_ch and tp_ch_used are not changed. Thus we also need to
4150     // check cmdline_row.
4151     if ((row < cmdline_row) && (cmdline_row <= Rows - p_ch))
4152 	clear_cmdline = TRUE;
4153 
4154     if (curtab->tp_old_Rows != Rows || (old_off != firstwin->w_winrow
4155 #ifdef FEAT_GUI_TABLINE
4156 			    && !gui_use_tabline()
4157 #endif
4158 		))
4159 	shell_new_rows();
4160     if (curtab->tp_old_Columns != Columns && starting == 0)
4161 	shell_new_columns();	// update window widths
4162 
4163 #if defined(FEAT_GUI)
4164     // When 'guioptions' includes 'L' or 'R' may have to remove or add
4165     // scrollbars.  Have to update them anyway.
4166     gui_may_update_scrollbars();
4167 #endif
4168 
4169     // Apply autocommands after updating the display, when 'rows' and
4170     // 'columns' have been set correctly.
4171     if (trigger_enter_autocmds)
4172     {
4173 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
4174 	if (old_curbuf != curbuf)
4175 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4176     }
4177 
4178     redraw_all_later(NOT_VALID);
4179 }
4180 
4181 /*
4182  * Go to tab page "n".  For ":tab N" and "Ngt".
4183  * When "n" is 9999 go to the last tab page.
4184  */
4185     void
4186 goto_tabpage(int n)
4187 {
4188     tabpage_T	*tp = NULL;  // shut up compiler
4189     tabpage_T	*ttp;
4190     int		i;
4191 
4192     if (text_locked())
4193     {
4194 	// Not allowed when editing the command line.
4195 	text_locked_msg();
4196 	return;
4197     }
4198 
4199     // If there is only one it can't work.
4200     if (first_tabpage->tp_next == NULL)
4201     {
4202 	if (n > 1)
4203 	    beep_flush();
4204 	return;
4205     }
4206 
4207     if (n == 0)
4208     {
4209 	// No count, go to next tab page, wrap around end.
4210 	if (curtab->tp_next == NULL)
4211 	    tp = first_tabpage;
4212 	else
4213 	    tp = curtab->tp_next;
4214     }
4215     else if (n < 0)
4216     {
4217 	// "gT": go to previous tab page, wrap around end.  "N gT" repeats
4218 	// this N times.
4219 	ttp = curtab;
4220 	for (i = n; i < 0; ++i)
4221 	{
4222 	    for (tp = first_tabpage; tp->tp_next != ttp && tp->tp_next != NULL;
4223 		    tp = tp->tp_next)
4224 		;
4225 	    ttp = tp;
4226 	}
4227     }
4228     else if (n == 9999)
4229     {
4230 	// Go to last tab page.
4231 	for (tp = first_tabpage; tp->tp_next != NULL; tp = tp->tp_next)
4232 	    ;
4233     }
4234     else
4235     {
4236 	// Go to tab page "n".
4237 	tp = find_tabpage(n);
4238 	if (tp == NULL)
4239 	{
4240 	    beep_flush();
4241 	    return;
4242 	}
4243     }
4244 
4245     goto_tabpage_tp(tp, TRUE, TRUE);
4246 
4247 #ifdef FEAT_GUI_TABLINE
4248     if (gui_use_tabline())
4249 	gui_mch_set_curtab(tabpage_index(curtab));
4250 #endif
4251 }
4252 
4253 /*
4254  * Go to tabpage "tp".
4255  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4256  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4257  * Note: doesn't update the GUI tab.
4258  */
4259     void
4260 goto_tabpage_tp(
4261     tabpage_T	*tp,
4262     int		trigger_enter_autocmds,
4263     int		trigger_leave_autocmds)
4264 {
4265     // Don't repeat a message in another tab page.
4266     set_keep_msg(NULL, 0);
4267 
4268     if (tp != curtab && leave_tabpage(tp->tp_curwin->w_buffer,
4269 					trigger_leave_autocmds) == OK)
4270     {
4271 	if (valid_tabpage(tp))
4272 	    enter_tabpage(tp, curbuf, trigger_enter_autocmds,
4273 		    trigger_leave_autocmds);
4274 	else
4275 	    enter_tabpage(curtab, curbuf, trigger_enter_autocmds,
4276 		    trigger_leave_autocmds);
4277     }
4278 }
4279 
4280 /*
4281  * Enter window "wp" in tab page "tp".
4282  * Also updates the GUI tab.
4283  */
4284     void
4285 goto_tabpage_win(tabpage_T *tp, win_T *wp)
4286 {
4287     goto_tabpage_tp(tp, TRUE, TRUE);
4288     if (curtab == tp && win_valid(wp))
4289     {
4290 	win_enter(wp, TRUE);
4291 # ifdef FEAT_GUI_TABLINE
4292 	if (gui_use_tabline())
4293 	    gui_mch_set_curtab(tabpage_index(curtab));
4294 # endif
4295     }
4296 }
4297 
4298 /*
4299  * Move the current tab page to after tab page "nr".
4300  */
4301     void
4302 tabpage_move(int nr)
4303 {
4304     int		n = 1;
4305     tabpage_T	*tp, *tp_dst;
4306 
4307     if (first_tabpage->tp_next == NULL)
4308 	return;
4309 
4310     for (tp = first_tabpage; tp->tp_next != NULL && n < nr; tp = tp->tp_next)
4311 	++n;
4312 
4313     if (tp == curtab || (nr > 0 && tp->tp_next != NULL
4314 						    && tp->tp_next == curtab))
4315 	return;
4316 
4317     tp_dst = tp;
4318 
4319     // Remove the current tab page from the list of tab pages.
4320     if (curtab == first_tabpage)
4321 	first_tabpage = curtab->tp_next;
4322     else
4323     {
4324 	FOR_ALL_TABPAGES(tp)
4325 	    if (tp->tp_next == curtab)
4326 		break;
4327 	if (tp == NULL)	// "cannot happen"
4328 	    return;
4329 	tp->tp_next = curtab->tp_next;
4330     }
4331 
4332     // Re-insert it at the specified position.
4333     if (nr <= 0)
4334     {
4335 	curtab->tp_next = first_tabpage;
4336 	first_tabpage = curtab;
4337     }
4338     else
4339     {
4340 	curtab->tp_next = tp_dst->tp_next;
4341 	tp_dst->tp_next = curtab;
4342     }
4343 
4344     // Need to redraw the tabline.  Tab page contents doesn't change.
4345     redraw_tabline = TRUE;
4346 }
4347 
4348 
4349 /*
4350  * Go to another window.
4351  * When jumping to another buffer, stop Visual mode.  Do this before
4352  * changing windows so we can yank the selection into the '*' register.
4353  * When jumping to another window on the same buffer, adjust its cursor
4354  * position to keep the same Visual area.
4355  */
4356     void
4357 win_goto(win_T *wp)
4358 {
4359 #ifdef FEAT_CONCEAL
4360     win_T	*owp = curwin;
4361 #endif
4362 
4363 #ifdef FEAT_PROP_POPUP
4364     if (ERROR_IF_ANY_POPUP_WINDOW)
4365 	return;
4366     if (popup_is_popup(wp))
4367     {
4368 	emsg(_("E366: Not allowed to enter a popup window"));
4369 	return;
4370     }
4371 #endif
4372     if (text_and_win_locked())
4373     {
4374 	beep_flush();
4375 	text_locked_msg();
4376 	return;
4377     }
4378     if (curbuf_locked())
4379 	return;
4380 
4381     if (wp->w_buffer != curbuf)
4382 	reset_VIsual_and_resel();
4383     else if (VIsual_active)
4384 	wp->w_cursor = curwin->w_cursor;
4385 
4386 #ifdef FEAT_GUI
4387     need_mouse_correct = TRUE;
4388 #endif
4389     win_enter(wp, TRUE);
4390 
4391 #ifdef FEAT_CONCEAL
4392     // Conceal cursor line in previous window, unconceal in current window.
4393     if (win_valid(owp) && owp->w_p_cole > 0 && !msg_scrolled)
4394 	redrawWinline(owp, owp->w_cursor.lnum);
4395     if (curwin->w_p_cole > 0 && !msg_scrolled)
4396 	need_cursor_line_redraw = TRUE;
4397 #endif
4398 }
4399 
4400 #if defined(FEAT_PERL) || defined(PROTO)
4401 /*
4402  * Find window number "winnr" (counting top to bottom).
4403  */
4404     win_T *
4405 win_find_nr(int winnr)
4406 {
4407     win_T	*wp;
4408 
4409     FOR_ALL_WINDOWS(wp)
4410 	if (--winnr == 0)
4411 	    break;
4412     return wp;
4413 }
4414 #endif
4415 
4416 #if ((defined(FEAT_PYTHON) || defined(FEAT_PYTHON3))) || defined(PROTO)
4417 /*
4418  * Find the tabpage for window "win".
4419  */
4420     tabpage_T *
4421 win_find_tabpage(win_T *win)
4422 {
4423     win_T	*wp;
4424     tabpage_T	*tp;
4425 
4426     FOR_ALL_TAB_WINDOWS(tp, wp)
4427 	    if (wp == win)
4428 		return tp;
4429     return NULL;
4430 }
4431 #endif
4432 
4433 /*
4434  * Get the above or below neighbor window of the specified window.
4435  *   up - TRUE for the above neighbor
4436  *   count - nth neighbor window
4437  * Returns the specified window if the neighbor is not found.
4438  */
4439     win_T *
4440 win_vert_neighbor(tabpage_T *tp, win_T *wp, int up, long count)
4441 {
4442     frame_T	*fr;
4443     frame_T	*nfr;
4444     frame_T	*foundfr;
4445 
4446 #ifdef FEAT_PROP_POPUP
4447     if (popup_is_popup(wp))
4448 	// popups don't have neighbors.
4449 	return NULL;
4450 #endif
4451     foundfr = wp->w_frame;
4452     while (count--)
4453     {
4454 	/*
4455 	 * First go upwards in the tree of frames until we find a upwards or
4456 	 * downwards neighbor.
4457 	 */
4458 	fr = foundfr;
4459 	for (;;)
4460 	{
4461 	    if (fr == tp->tp_topframe)
4462 		goto end;
4463 	    if (up)
4464 		nfr = fr->fr_prev;
4465 	    else
4466 		nfr = fr->fr_next;
4467 	    if (fr->fr_parent->fr_layout == FR_COL && nfr != NULL)
4468 		break;
4469 	    fr = fr->fr_parent;
4470 	}
4471 
4472 	/*
4473 	 * Now go downwards to find the bottom or top frame in it.
4474 	 */
4475 	for (;;)
4476 	{
4477 	    if (nfr->fr_layout == FR_LEAF)
4478 	    {
4479 		foundfr = nfr;
4480 		break;
4481 	    }
4482 	    fr = nfr->fr_child;
4483 	    if (nfr->fr_layout == FR_ROW)
4484 	    {
4485 		// Find the frame at the cursor row.
4486 		while (fr->fr_next != NULL
4487 			&& frame2win(fr)->w_wincol + fr->fr_width
4488 					 <= wp->w_wincol + wp->w_wcol)
4489 		    fr = fr->fr_next;
4490 	    }
4491 	    if (nfr->fr_layout == FR_COL && up)
4492 		while (fr->fr_next != NULL)
4493 		    fr = fr->fr_next;
4494 	    nfr = fr;
4495 	}
4496     }
4497 end:
4498     return foundfr != NULL ? foundfr->fr_win : NULL;
4499 }
4500 
4501 /*
4502  * Move to window above or below "count" times.
4503  */
4504     static void
4505 win_goto_ver(
4506     int		up,		// TRUE to go to win above
4507     long	count)
4508 {
4509     win_T	*win;
4510 
4511 #ifdef FEAT_PROP_POPUP
4512     if (ERROR_IF_TERM_POPUP_WINDOW)
4513 	return;
4514 #endif
4515     win = win_vert_neighbor(curtab, curwin, up, count);
4516     if (win != NULL)
4517 	win_goto(win);
4518 }
4519 
4520 /*
4521  * Get the left or right neighbor window of the specified window.
4522  *   left - TRUE for the left neighbor
4523  *   count - nth neighbor window
4524  * Returns the specified window if the neighbor is not found.
4525  */
4526     win_T *
4527 win_horz_neighbor(tabpage_T *tp, win_T *wp, int left, long count)
4528 {
4529     frame_T	*fr;
4530     frame_T	*nfr;
4531     frame_T	*foundfr;
4532 
4533 #ifdef FEAT_PROP_POPUP
4534     if (popup_is_popup(wp))
4535 	// popups don't have neighbors.
4536 	return NULL;
4537 #endif
4538     foundfr = wp->w_frame;
4539     while (count--)
4540     {
4541 	/*
4542 	 * First go upwards in the tree of frames until we find a left or
4543 	 * right neighbor.
4544 	 */
4545 	fr = foundfr;
4546 	for (;;)
4547 	{
4548 	    if (fr == tp->tp_topframe)
4549 		goto end;
4550 	    if (left)
4551 		nfr = fr->fr_prev;
4552 	    else
4553 		nfr = fr->fr_next;
4554 	    if (fr->fr_parent->fr_layout == FR_ROW && nfr != NULL)
4555 		break;
4556 	    fr = fr->fr_parent;
4557 	}
4558 
4559 	/*
4560 	 * Now go downwards to find the leftmost or rightmost frame in it.
4561 	 */
4562 	for (;;)
4563 	{
4564 	    if (nfr->fr_layout == FR_LEAF)
4565 	    {
4566 		foundfr = nfr;
4567 		break;
4568 	    }
4569 	    fr = nfr->fr_child;
4570 	    if (nfr->fr_layout == FR_COL)
4571 	    {
4572 		// Find the frame at the cursor row.
4573 		while (fr->fr_next != NULL
4574 			&& frame2win(fr)->w_winrow + fr->fr_height
4575 					 <= wp->w_winrow + wp->w_wrow)
4576 		    fr = fr->fr_next;
4577 	    }
4578 	    if (nfr->fr_layout == FR_ROW && left)
4579 		while (fr->fr_next != NULL)
4580 		    fr = fr->fr_next;
4581 	    nfr = fr;
4582 	}
4583     }
4584 end:
4585     return foundfr != NULL ? foundfr->fr_win : NULL;
4586 }
4587 
4588 /*
4589  * Move to left or right window.
4590  */
4591     static void
4592 win_goto_hor(
4593     int		left,		// TRUE to go to left win
4594     long	count)
4595 {
4596     win_T	*win;
4597 
4598 #ifdef FEAT_PROP_POPUP
4599     if (ERROR_IF_TERM_POPUP_WINDOW)
4600 	return;
4601 #endif
4602     win = win_horz_neighbor(curtab, curwin, left, count);
4603     if (win != NULL)
4604 	win_goto(win);
4605 }
4606 
4607 /*
4608  * Make window "wp" the current window.
4609  */
4610     void
4611 win_enter(win_T *wp, int undo_sync)
4612 {
4613     win_enter_ext(wp, undo_sync, FALSE, FALSE, TRUE, TRUE);
4614 }
4615 
4616 /*
4617  * Make window wp the current window.
4618  * Can be called with "curwin_invalid" TRUE, which means that curwin has just
4619  * been closed and isn't valid.
4620  */
4621     static void
4622 win_enter_ext(
4623     win_T	*wp,
4624     int		undo_sync,
4625     int		curwin_invalid,
4626     int		trigger_new_autocmds,
4627     int		trigger_enter_autocmds,
4628     int		trigger_leave_autocmds)
4629 {
4630     int		other_buffer = FALSE;
4631 
4632     if (wp == curwin && !curwin_invalid)	// nothing to do
4633 	return;
4634 
4635 #ifdef FEAT_JOB_CHANNEL
4636     if (!curwin_invalid)
4637 	leaving_window(curwin);
4638 #endif
4639 
4640     if (!curwin_invalid && trigger_leave_autocmds)
4641     {
4642 	/*
4643 	 * Be careful: If autocommands delete the window, return now.
4644 	 */
4645 	if (wp->w_buffer != curbuf)
4646 	{
4647 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4648 	    other_buffer = TRUE;
4649 	    if (!win_valid(wp))
4650 		return;
4651 	}
4652 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4653 	if (!win_valid(wp))
4654 	    return;
4655 #ifdef FEAT_EVAL
4656 	// autocmds may abort script processing
4657 	if (aborting())
4658 	    return;
4659 #endif
4660     }
4661 
4662     // sync undo before leaving the current buffer
4663     if (undo_sync && curbuf != wp->w_buffer)
4664 	u_sync(FALSE);
4665 
4666     // Might need to scroll the old window before switching, e.g., when the
4667     // cursor was moved.
4668     update_topline();
4669 
4670     // may have to copy the buffer options when 'cpo' contains 'S'
4671     if (wp->w_buffer != curbuf)
4672 	buf_copy_options(wp->w_buffer, BCO_ENTER | BCO_NOHELP);
4673     if (!curwin_invalid)
4674     {
4675 	prevwin = curwin;	// remember for CTRL-W p
4676 	curwin->w_redr_status = TRUE;
4677     }
4678     curwin = wp;
4679     curbuf = wp->w_buffer;
4680     check_cursor();
4681     if (!virtual_active())
4682 	curwin->w_cursor.coladd = 0;
4683     changed_line_abv_curs();	// assume cursor position needs updating
4684 
4685     if (curwin->w_localdir != NULL || curtab->tp_localdir != NULL)
4686     {
4687 	char_u	*dirname;
4688 
4689 	// Window or tab has a local directory: Save current directory as
4690 	// global directory (unless that was done already) and change to the
4691 	// local directory.
4692 	if (globaldir == NULL)
4693 	{
4694 	    char_u	cwd[MAXPATHL];
4695 
4696 	    if (mch_dirname(cwd, MAXPATHL) == OK)
4697 		globaldir = vim_strsave(cwd);
4698 	}
4699 	if (curwin->w_localdir != NULL)
4700 	    dirname = curwin->w_localdir;
4701 	else
4702 	    dirname = curtab->tp_localdir;
4703 
4704 	if (mch_chdir((char *)dirname) == 0)
4705 	    shorten_fnames(TRUE);
4706     }
4707     else if (globaldir != NULL)
4708     {
4709 	// Window doesn't have a local directory and we are not in the global
4710 	// directory: Change to the global directory.
4711 	vim_ignored = mch_chdir((char *)globaldir);
4712 	VIM_CLEAR(globaldir);
4713 	shorten_fnames(TRUE);
4714     }
4715 
4716 #ifdef FEAT_JOB_CHANNEL
4717     entering_window(curwin);
4718 #endif
4719     // Careful: autocommands may close the window and make "wp" invalid
4720     if (trigger_new_autocmds)
4721 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
4722     if (trigger_enter_autocmds)
4723     {
4724 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
4725 	if (other_buffer)
4726 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4727     }
4728 
4729 #ifdef FEAT_TITLE
4730     maketitle();
4731 #endif
4732     curwin->w_redr_status = TRUE;
4733 #ifdef FEAT_TERMINAL
4734     if (bt_terminal(curwin->w_buffer))
4735 	// terminal is likely in another mode
4736 	redraw_mode = TRUE;
4737 #endif
4738     redraw_tabline = TRUE;
4739     if (restart_edit)
4740 	redraw_later(VALID);	// causes status line redraw
4741 
4742     // set window height to desired minimal value
4743     if (curwin->w_height < p_wh && !curwin->w_p_wfh
4744 #ifdef FEAT_PROP_POPUP
4745 	    && !popup_is_popup(curwin)
4746 #endif
4747 	    )
4748 	win_setheight((int)p_wh);
4749     else if (curwin->w_height == 0)
4750 	win_setheight(1);
4751 
4752     // set window width to desired minimal value
4753     if (curwin->w_width < p_wiw && !curwin->w_p_wfw)
4754 	win_setwidth((int)p_wiw);
4755 
4756     setmouse();			// in case jumped to/from help buffer
4757 
4758     // Change directories when the 'acd' option is set.
4759     DO_AUTOCHDIR;
4760 }
4761 
4762 
4763 /*
4764  * Jump to the first open window that contains buffer "buf", if one exists.
4765  * Returns a pointer to the window found, otherwise NULL.
4766  */
4767     win_T *
4768 buf_jump_open_win(buf_T *buf)
4769 {
4770     win_T	*wp = NULL;
4771 
4772     if (curwin->w_buffer == buf)
4773 	wp = curwin;
4774     else
4775 	FOR_ALL_WINDOWS(wp)
4776 	    if (wp->w_buffer == buf)
4777 		break;
4778     if (wp != NULL)
4779 	win_enter(wp, FALSE);
4780     return wp;
4781 }
4782 
4783 /*
4784  * Jump to the first open window in any tab page that contains buffer "buf",
4785  * if one exists.
4786  * Returns a pointer to the window found, otherwise NULL.
4787  */
4788     win_T *
4789 buf_jump_open_tab(buf_T *buf)
4790 {
4791     win_T	*wp = buf_jump_open_win(buf);
4792     tabpage_T	*tp;
4793 
4794     if (wp != NULL)
4795 	return wp;
4796 
4797     FOR_ALL_TABPAGES(tp)
4798 	if (tp != curtab)
4799 	{
4800 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
4801 		if (wp->w_buffer == buf)
4802 		    break;
4803 	    if (wp != NULL)
4804 	    {
4805 		goto_tabpage_win(tp, wp);
4806 		if (curwin != wp)
4807 		    wp = NULL;	// something went wrong
4808 		break;
4809 	    }
4810 	}
4811     return wp;
4812 }
4813 
4814 static int last_win_id = LOWEST_WIN_ID - 1;
4815 
4816 /*
4817  * Allocate a window structure and link it in the window list when "hidden" is
4818  * FALSE.
4819  */
4820     static win_T *
4821 win_alloc(win_T *after UNUSED, int hidden UNUSED)
4822 {
4823     win_T	*new_wp;
4824 
4825     /*
4826      * allocate window structure and linesizes arrays
4827      */
4828     new_wp = ALLOC_CLEAR_ONE(win_T);
4829     if (new_wp == NULL)
4830 	return NULL;
4831 
4832     if (win_alloc_lines(new_wp) == FAIL)
4833     {
4834 	vim_free(new_wp);
4835 	return NULL;
4836     }
4837 
4838     new_wp->w_id = ++last_win_id;
4839 
4840 #ifdef FEAT_EVAL
4841     // init w: variables
4842     new_wp->w_vars = dict_alloc();
4843     if (new_wp->w_vars == NULL)
4844     {
4845 	win_free_lsize(new_wp);
4846 	vim_free(new_wp);
4847 	return NULL;
4848     }
4849     init_var_dict(new_wp->w_vars, &new_wp->w_winvar, VAR_SCOPE);
4850 #endif
4851 
4852     // Don't execute autocommands while the window is not properly
4853     // initialized yet.  gui_create_scrollbar() may trigger a FocusGained
4854     // event.
4855     block_autocmds();
4856 
4857     /*
4858      * link the window in the window list
4859      */
4860     if (!hidden)
4861 	win_append(after, new_wp);
4862     new_wp->w_wincol = 0;
4863     new_wp->w_width = Columns;
4864 
4865     // position the display and the cursor at the top of the file.
4866     new_wp->w_topline = 1;
4867 #ifdef FEAT_DIFF
4868     new_wp->w_topfill = 0;
4869 #endif
4870     new_wp->w_botline = 2;
4871     new_wp->w_cursor.lnum = 1;
4872     new_wp->w_scbind_pos = 1;
4873 
4874     // use global option value for global-local options
4875     new_wp->w_p_so = -1;
4876     new_wp->w_p_siso = -1;
4877 
4878     // We won't calculate w_fraction until resizing the window
4879     new_wp->w_fraction = 0;
4880     new_wp->w_prev_fraction_row = -1;
4881 
4882 #ifdef FEAT_GUI
4883     if (gui.in_use)
4884     {
4885 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_LEFT],
4886 		SBAR_LEFT, new_wp);
4887 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_RIGHT],
4888 		SBAR_RIGHT, new_wp);
4889     }
4890 #endif
4891 #ifdef FEAT_FOLDING
4892     foldInitWin(new_wp);
4893 #endif
4894     unblock_autocmds();
4895 #ifdef FEAT_SEARCH_EXTRA
4896     new_wp->w_match_head = NULL;
4897     new_wp->w_next_match_id = 4;
4898 #endif
4899     return new_wp;
4900 }
4901 
4902 /*
4903  * Remove window 'wp' from the window list and free the structure.
4904  */
4905     static void
4906 win_free(
4907     win_T	*wp,
4908     tabpage_T	*tp)		// tab page "win" is in, NULL for current
4909 {
4910     int		i;
4911     buf_T	*buf;
4912     wininfo_T	*wip;
4913 
4914 #ifdef FEAT_FOLDING
4915     clearFolding(wp);
4916 #endif
4917 
4918     // reduce the reference count to the argument list.
4919     alist_unlink(wp->w_alist);
4920 
4921     // Don't execute autocommands while the window is halfway being deleted.
4922     // gui_mch_destroy_scrollbar() may trigger a FocusGained event.
4923     block_autocmds();
4924 
4925 #ifdef FEAT_LUA
4926     lua_window_free(wp);
4927 #endif
4928 
4929 #ifdef FEAT_MZSCHEME
4930     mzscheme_window_free(wp);
4931 #endif
4932 
4933 #ifdef FEAT_PERL
4934     perl_win_free(wp);
4935 #endif
4936 
4937 #ifdef FEAT_PYTHON
4938     python_window_free(wp);
4939 #endif
4940 
4941 #ifdef FEAT_PYTHON3
4942     python3_window_free(wp);
4943 #endif
4944 
4945 #ifdef FEAT_TCL
4946     tcl_window_free(wp);
4947 #endif
4948 
4949 #ifdef FEAT_RUBY
4950     ruby_window_free(wp);
4951 #endif
4952 
4953     clear_winopt(&wp->w_onebuf_opt);
4954     clear_winopt(&wp->w_allbuf_opt);
4955 
4956 #ifdef FEAT_EVAL
4957     vars_clear(&wp->w_vars->dv_hashtab);	// free all w: variables
4958     hash_init(&wp->w_vars->dv_hashtab);
4959     unref_var_dict(wp->w_vars);
4960 #endif
4961 
4962     {
4963 	tabpage_T	*ttp;
4964 
4965 	if (prevwin == wp)
4966 	    prevwin = NULL;
4967 	FOR_ALL_TABPAGES(ttp)
4968 	    if (ttp->tp_prevwin == wp)
4969 		ttp->tp_prevwin = NULL;
4970     }
4971     win_free_lsize(wp);
4972 
4973     for (i = 0; i < wp->w_tagstacklen; ++i)
4974     {
4975 	vim_free(wp->w_tagstack[i].tagname);
4976 	vim_free(wp->w_tagstack[i].user_data);
4977     }
4978     vim_free(wp->w_localdir);
4979     vim_free(wp->w_prevdir);
4980 
4981     // Remove the window from the b_wininfo lists, it may happen that the
4982     // freed memory is re-used for another window.
4983     FOR_ALL_BUFFERS(buf)
4984 	FOR_ALL_BUF_WININFO(buf, wip)
4985 	    if (wip->wi_win == wp)
4986 		wip->wi_win = NULL;
4987 
4988 #ifdef FEAT_SEARCH_EXTRA
4989     clear_matches(wp);
4990 #endif
4991 
4992 #ifdef FEAT_JUMPLIST
4993     free_jumplist(wp);
4994 #endif
4995 
4996 #ifdef FEAT_QUICKFIX
4997     qf_free_all(wp);
4998 #endif
4999 
5000 #ifdef FEAT_GUI
5001     if (gui.in_use)
5002     {
5003 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_LEFT]);
5004 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_RIGHT]);
5005     }
5006 #endif // FEAT_GUI
5007 
5008 #ifdef FEAT_MENU
5009     remove_winbar(wp);
5010 #endif
5011 #ifdef FEAT_PROP_POPUP
5012     free_callback(&wp->w_close_cb);
5013     free_callback(&wp->w_filter_cb);
5014     for (i = 0; i < 4; ++i)
5015 	VIM_CLEAR(wp->w_border_highlight[i]);
5016     vim_free(wp->w_scrollbar_highlight);
5017     vim_free(wp->w_thumb_highlight);
5018     vim_free(wp->w_popup_title);
5019     list_unref(wp->w_popup_mask);
5020     vim_free(wp->w_popup_mask_cells);
5021 #endif
5022 
5023 #ifdef FEAT_SYN_HL
5024     vim_free(wp->w_p_cc_cols);
5025 #endif
5026 
5027     if (win_valid_any_tab(wp))
5028 	win_remove(wp, tp);
5029     if (autocmd_busy)
5030     {
5031 	wp->w_next = au_pending_free_win;
5032 	au_pending_free_win = wp;
5033     }
5034     else
5035 	vim_free(wp);
5036 
5037     unblock_autocmds();
5038 }
5039 
5040 /*
5041  * Return TRUE if "wp" is not in the list of windows: the autocmd window or a
5042  * popup window.
5043  */
5044     static int
5045 win_unlisted(win_T *wp)
5046 {
5047     return wp == aucmd_win || WIN_IS_POPUP(wp);
5048 }
5049 
5050 #if defined(FEAT_PROP_POPUP) || defined(PROTO)
5051 /*
5052  * Free a popup window.  This does not take the window out of the window list
5053  * and assumes there is only one toplevel frame, no split.
5054  */
5055     void
5056 win_free_popup(win_T *win)
5057 {
5058     if (bt_popup(win->w_buffer))
5059 	win_close_buffer(win, DOBUF_WIPE_REUSE, FALSE);
5060     else
5061 	close_buffer(win, win->w_buffer, 0, FALSE, FALSE);
5062 # if defined(FEAT_TIMERS)
5063     if (win->w_popup_timer != NULL)
5064 	stop_timer(win->w_popup_timer);
5065 # endif
5066     vim_free(win->w_frame);
5067     win_free(win, NULL);
5068 }
5069 #endif
5070 
5071 /*
5072  * Append window "wp" in the window list after window "after".
5073  */
5074     static void
5075 win_append(win_T *after, win_T *wp)
5076 {
5077     win_T	*before;
5078 
5079     if (after == NULL)	    // after NULL is in front of the first
5080 	before = firstwin;
5081     else
5082 	before = after->w_next;
5083 
5084     wp->w_next = before;
5085     wp->w_prev = after;
5086     if (after == NULL)
5087 	firstwin = wp;
5088     else
5089 	after->w_next = wp;
5090     if (before == NULL)
5091 	lastwin = wp;
5092     else
5093 	before->w_prev = wp;
5094 }
5095 
5096 /*
5097  * Remove a window from the window list.
5098  */
5099     void
5100 win_remove(
5101     win_T	*wp,
5102     tabpage_T	*tp)		// tab page "win" is in, NULL for current
5103 {
5104     if (wp->w_prev != NULL)
5105 	wp->w_prev->w_next = wp->w_next;
5106     else if (tp == NULL)
5107 	firstwin = curtab->tp_firstwin = wp->w_next;
5108     else
5109 	tp->tp_firstwin = wp->w_next;
5110 
5111     if (wp->w_next != NULL)
5112 	wp->w_next->w_prev = wp->w_prev;
5113     else if (tp == NULL)
5114 	lastwin = curtab->tp_lastwin = wp->w_prev;
5115     else
5116 	tp->tp_lastwin = wp->w_prev;
5117 }
5118 
5119 /*
5120  * Append frame "frp" in a frame list after frame "after".
5121  */
5122     static void
5123 frame_append(frame_T *after, frame_T *frp)
5124 {
5125     frp->fr_next = after->fr_next;
5126     after->fr_next = frp;
5127     if (frp->fr_next != NULL)
5128 	frp->fr_next->fr_prev = frp;
5129     frp->fr_prev = after;
5130 }
5131 
5132 /*
5133  * Insert frame "frp" in a frame list before frame "before".
5134  */
5135     static void
5136 frame_insert(frame_T *before, frame_T *frp)
5137 {
5138     frp->fr_next = before;
5139     frp->fr_prev = before->fr_prev;
5140     before->fr_prev = frp;
5141     if (frp->fr_prev != NULL)
5142 	frp->fr_prev->fr_next = frp;
5143     else
5144 	frp->fr_parent->fr_child = frp;
5145 }
5146 
5147 /*
5148  * Remove a frame from a frame list.
5149  */
5150     static void
5151 frame_remove(frame_T *frp)
5152 {
5153     if (frp->fr_prev != NULL)
5154 	frp->fr_prev->fr_next = frp->fr_next;
5155     else
5156     {
5157 	frp->fr_parent->fr_child = frp->fr_next;
5158 	// special case: topframe->fr_child == frp
5159 	if (topframe->fr_child == frp)
5160 	    topframe->fr_child = frp->fr_next;
5161     }
5162     if (frp->fr_next != NULL)
5163 	frp->fr_next->fr_prev = frp->fr_prev;
5164 }
5165 
5166 /*
5167  * Allocate w_lines[] for window "wp".
5168  * Return FAIL for failure, OK for success.
5169  */
5170     int
5171 win_alloc_lines(win_T *wp)
5172 {
5173     wp->w_lines_valid = 0;
5174     wp->w_lines = ALLOC_CLEAR_MULT(wline_T, Rows );
5175     if (wp->w_lines == NULL)
5176 	return FAIL;
5177     return OK;
5178 }
5179 
5180 /*
5181  * free lsize arrays for a window
5182  */
5183     void
5184 win_free_lsize(win_T *wp)
5185 {
5186     // TODO: why would wp be NULL here?
5187     if (wp != NULL)
5188 	VIM_CLEAR(wp->w_lines);
5189 }
5190 
5191 /*
5192  * Called from win_new_shellsize() after Rows changed.
5193  * This only does the current tab page, others must be done when made active.
5194  */
5195     void
5196 shell_new_rows(void)
5197 {
5198     int		h = (int)ROWS_AVAIL;
5199 
5200     if (firstwin == NULL)	// not initialized yet
5201 	return;
5202     if (h < frame_minheight(topframe, NULL))
5203 	h = frame_minheight(topframe, NULL);
5204 
5205     // First try setting the heights of windows with 'winfixheight'.  If
5206     // that doesn't result in the right height, forget about that option.
5207     frame_new_height(topframe, h, FALSE, TRUE);
5208     if (!frame_check_height(topframe, h))
5209 	frame_new_height(topframe, h, FALSE, FALSE);
5210 
5211     (void)win_comp_pos();		// recompute w_winrow and w_wincol
5212     compute_cmdrow();
5213     curtab->tp_ch_used = p_ch;
5214 
5215 #if 0
5216     // Disabled: don't want making the screen smaller make a window larger.
5217     if (p_ea)
5218 	win_equal(curwin, FALSE, 'v');
5219 #endif
5220 }
5221 
5222 /*
5223  * Called from win_new_shellsize() after Columns changed.
5224  */
5225     void
5226 shell_new_columns(void)
5227 {
5228     if (firstwin == NULL)	// not initialized yet
5229 	return;
5230 
5231     // First try setting the widths of windows with 'winfixwidth'.  If that
5232     // doesn't result in the right width, forget about that option.
5233     frame_new_width(topframe, (int)Columns, FALSE, TRUE);
5234     if (!frame_check_width(topframe, Columns))
5235 	frame_new_width(topframe, (int)Columns, FALSE, FALSE);
5236 
5237     (void)win_comp_pos();		// recompute w_winrow and w_wincol
5238 #if 0
5239     // Disabled: don't want making the screen smaller make a window larger.
5240     if (p_ea)
5241 	win_equal(curwin, FALSE, 'h');
5242 #endif
5243 }
5244 
5245 #if defined(FEAT_CMDWIN) || defined(PROTO)
5246 /*
5247  * Save the size of all windows in "gap".
5248  */
5249     void
5250 win_size_save(garray_T *gap)
5251 
5252 {
5253     win_T	*wp;
5254 
5255     ga_init2(gap, (int)sizeof(int), 1);
5256     if (ga_grow(gap, win_count() * 2 + 1) == OK)
5257     {
5258 	// first entry is value of 'lines'
5259 	((int *)gap->ga_data)[gap->ga_len++] = Rows;
5260 
5261 	FOR_ALL_WINDOWS(wp)
5262 	{
5263 	    ((int *)gap->ga_data)[gap->ga_len++] =
5264 					       wp->w_width + wp->w_vsep_width;
5265 	    ((int *)gap->ga_data)[gap->ga_len++] = wp->w_height;
5266 	}
5267     }
5268 }
5269 
5270 /*
5271  * Restore window sizes, but only if the number of windows is still the same
5272  * and 'lines' didn't change.
5273  * Does not free the growarray.
5274  */
5275     void
5276 win_size_restore(garray_T *gap)
5277 {
5278     win_T	*wp;
5279     int		i, j;
5280 
5281     if (win_count() * 2 + 1 == gap->ga_len
5282 	    && ((int *)gap->ga_data)[0] == Rows)
5283     {
5284 	// The order matters, because frames contain other frames, but it's
5285 	// difficult to get right. The easy way out is to do it twice.
5286 	for (j = 0; j < 2; ++j)
5287 	{
5288 	    i = 1;
5289 	    FOR_ALL_WINDOWS(wp)
5290 	    {
5291 		frame_setwidth(wp->w_frame, ((int *)gap->ga_data)[i++]);
5292 		win_setheight_win(((int *)gap->ga_data)[i++], wp);
5293 	    }
5294 	}
5295 	// recompute the window positions
5296 	(void)win_comp_pos();
5297     }
5298 }
5299 #endif // FEAT_CMDWIN
5300 
5301 /*
5302  * Update the position for all windows, using the width and height of the
5303  * frames.
5304  * Returns the row just after the last window.
5305  */
5306     int
5307 win_comp_pos(void)
5308 {
5309     int		row = tabline_height();
5310     int		col = 0;
5311 
5312     frame_comp_pos(topframe, &row, &col);
5313     return row;
5314 }
5315 
5316 /*
5317  * Update the position of the windows in frame "topfrp", using the width and
5318  * height of the frames.
5319  * "*row" and "*col" are the top-left position of the frame.  They are updated
5320  * to the bottom-right position plus one.
5321  */
5322     static void
5323 frame_comp_pos(frame_T *topfrp, int *row, int *col)
5324 {
5325     win_T	*wp;
5326     frame_T	*frp;
5327     int		startcol;
5328     int		startrow;
5329     int		h;
5330 
5331     wp = topfrp->fr_win;
5332     if (wp != NULL)
5333     {
5334 	if (wp->w_winrow != *row || wp->w_wincol != *col)
5335 	{
5336 	    // position changed, redraw
5337 	    wp->w_winrow = *row;
5338 	    wp->w_wincol = *col;
5339 	    redraw_win_later(wp, NOT_VALID);
5340 	    wp->w_redr_status = TRUE;
5341 	}
5342 	// WinBar will not show if the window height is zero
5343 	h = VISIBLE_HEIGHT(wp) + wp->w_status_height;
5344 	*row += h > topfrp->fr_height ? topfrp->fr_height : h;
5345 	*col += wp->w_width + wp->w_vsep_width;
5346     }
5347     else
5348     {
5349 	startrow = *row;
5350 	startcol = *col;
5351 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
5352 	{
5353 	    if (topfrp->fr_layout == FR_ROW)
5354 		*row = startrow;	// all frames are at the same row
5355 	    else
5356 		*col = startcol;	// all frames are at the same col
5357 	    frame_comp_pos(frp, row, col);
5358 	}
5359     }
5360 }
5361 
5362 /*
5363  * Set current window height and take care of repositioning other windows to
5364  * fit around it.
5365  */
5366     void
5367 win_setheight(int height)
5368 {
5369     win_setheight_win(height, curwin);
5370 }
5371 
5372 /*
5373  * Set the window height of window "win" and take care of repositioning other
5374  * windows to fit around it.
5375  */
5376     void
5377 win_setheight_win(int height, win_T *win)
5378 {
5379     int		row;
5380 
5381     if (win == curwin)
5382     {
5383 	// Always keep current window at least one line high, even when
5384 	// 'winminheight' is zero.
5385 	if (height < p_wmh)
5386 	    height = p_wmh;
5387 	if (height == 0)
5388 	    height = 1;
5389 	height += WINBAR_HEIGHT(curwin);
5390     }
5391 
5392     frame_setheight(win->w_frame, height + win->w_status_height);
5393 
5394     // recompute the window positions
5395     row = win_comp_pos();
5396 
5397     /*
5398      * If there is extra space created between the last window and the command
5399      * line, clear it.
5400      */
5401     if (full_screen && msg_scrolled == 0 && row < cmdline_row)
5402 	screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5403     cmdline_row = row;
5404     msg_row = row;
5405     msg_col = 0;
5406 
5407     redraw_all_later(NOT_VALID);
5408 }
5409 
5410 /*
5411  * Set the height of a frame to "height" and take care that all frames and
5412  * windows inside it are resized.  Also resize frames on the left and right if
5413  * the are in the same FR_ROW frame.
5414  *
5415  * Strategy:
5416  * If the frame is part of a FR_COL frame, try fitting the frame in that
5417  * frame.  If that doesn't work (the FR_COL frame is too small), recursively
5418  * go to containing frames to resize them and make room.
5419  * If the frame is part of a FR_ROW frame, all frames must be resized as well.
5420  * Check for the minimal height of the FR_ROW frame.
5421  * At the top level we can also use change the command line height.
5422  */
5423     static void
5424 frame_setheight(frame_T *curfrp, int height)
5425 {
5426     int		room;		// total number of lines available
5427     int		take;		// number of lines taken from other windows
5428     int		room_cmdline;	// lines available from cmdline
5429     int		run;
5430     frame_T	*frp;
5431     int		h;
5432     int		room_reserved;
5433 
5434     // If the height already is the desired value, nothing to do.
5435     if (curfrp->fr_height == height)
5436 	return;
5437 
5438     if (curfrp->fr_parent == NULL)
5439     {
5440 	// topframe: can only change the command line
5441 	if (height > ROWS_AVAIL)
5442 	    height = ROWS_AVAIL;
5443 	if (height > 0)
5444 	    frame_new_height(curfrp, height, FALSE, FALSE);
5445     }
5446     else if (curfrp->fr_parent->fr_layout == FR_ROW)
5447     {
5448 	// Row of frames: Also need to resize frames left and right of this
5449 	// one.  First check for the minimal height of these.
5450 	h = frame_minheight(curfrp->fr_parent, NULL);
5451 	if (height < h)
5452 	    height = h;
5453 	frame_setheight(curfrp->fr_parent, height);
5454     }
5455     else
5456     {
5457 	/*
5458 	 * Column of frames: try to change only frames in this column.
5459 	 */
5460 	/*
5461 	 * Do this twice:
5462 	 * 1: compute room available, if it's not enough try resizing the
5463 	 *    containing frame.
5464 	 * 2: compute the room available and adjust the height to it.
5465 	 * Try not to reduce the height of a window with 'winfixheight' set.
5466 	 */
5467 	for (run = 1; run <= 2; ++run)
5468 	{
5469 	    room = 0;
5470 	    room_reserved = 0;
5471 	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
5472 	    {
5473 		if (frp != curfrp
5474 			&& frp->fr_win != NULL
5475 			&& frp->fr_win->w_p_wfh)
5476 		    room_reserved += frp->fr_height;
5477 		room += frp->fr_height;
5478 		if (frp != curfrp)
5479 		    room -= frame_minheight(frp, NULL);
5480 	    }
5481 	    if (curfrp->fr_width != Columns)
5482 		room_cmdline = 0;
5483 	    else
5484 	    {
5485 		room_cmdline = Rows - p_ch - (lastwin->w_winrow
5486 						+ VISIBLE_HEIGHT(lastwin)
5487 						+ lastwin->w_status_height);
5488 		if (room_cmdline < 0)
5489 		    room_cmdline = 0;
5490 	    }
5491 
5492 	    if (height <= room + room_cmdline)
5493 		break;
5494 	    if (run == 2 || curfrp->fr_width == Columns)
5495 	    {
5496 		if (height > room + room_cmdline)
5497 		    height = room + room_cmdline;
5498 		break;
5499 	    }
5500 	    frame_setheight(curfrp->fr_parent, height
5501 		+ frame_minheight(curfrp->fr_parent, NOWIN) - (int)p_wmh - 1);
5502 	}
5503 
5504 	/*
5505 	 * Compute the number of lines we will take from others frames (can be
5506 	 * negative!).
5507 	 */
5508 	take = height - curfrp->fr_height;
5509 
5510 	// If there is not enough room, also reduce the height of a window
5511 	// with 'winfixheight' set.
5512 	if (height > room + room_cmdline - room_reserved)
5513 	    room_reserved = room + room_cmdline - height;
5514 	// If there is only a 'winfixheight' window and making the
5515 	// window smaller, need to make the other window taller.
5516 	if (take < 0 && room - curfrp->fr_height < room_reserved)
5517 	    room_reserved = 0;
5518 
5519 	if (take > 0 && room_cmdline > 0)
5520 	{
5521 	    // use lines from cmdline first
5522 	    if (take < room_cmdline)
5523 		room_cmdline = take;
5524 	    take -= room_cmdline;
5525 	    topframe->fr_height += room_cmdline;
5526 	}
5527 
5528 	/*
5529 	 * set the current frame to the new height
5530 	 */
5531 	frame_new_height(curfrp, height, FALSE, FALSE);
5532 
5533 	/*
5534 	 * First take lines from the frames after the current frame.  If
5535 	 * that is not enough, takes lines from frames above the current
5536 	 * frame.
5537 	 */
5538 	for (run = 0; run < 2; ++run)
5539 	{
5540 	    if (run == 0)
5541 		frp = curfrp->fr_next;	// 1st run: start with next window
5542 	    else
5543 		frp = curfrp->fr_prev;	// 2nd run: start with prev window
5544 	    while (frp != NULL && take != 0)
5545 	    {
5546 		h = frame_minheight(frp, NULL);
5547 		if (room_reserved > 0
5548 			&& frp->fr_win != NULL
5549 			&& frp->fr_win->w_p_wfh)
5550 		{
5551 		    if (room_reserved >= frp->fr_height)
5552 			room_reserved -= frp->fr_height;
5553 		    else
5554 		    {
5555 			if (frp->fr_height - room_reserved > take)
5556 			    room_reserved = frp->fr_height - take;
5557 			take -= frp->fr_height - room_reserved;
5558 			frame_new_height(frp, room_reserved, FALSE, FALSE);
5559 			room_reserved = 0;
5560 		    }
5561 		}
5562 		else
5563 		{
5564 		    if (frp->fr_height - take < h)
5565 		    {
5566 			take -= frp->fr_height - h;
5567 			frame_new_height(frp, h, FALSE, FALSE);
5568 		    }
5569 		    else
5570 		    {
5571 			frame_new_height(frp, frp->fr_height - take,
5572 								FALSE, FALSE);
5573 			take = 0;
5574 		    }
5575 		}
5576 		if (run == 0)
5577 		    frp = frp->fr_next;
5578 		else
5579 		    frp = frp->fr_prev;
5580 	    }
5581 	}
5582     }
5583 }
5584 
5585 /*
5586  * Set current window width and take care of repositioning other windows to
5587  * fit around it.
5588  */
5589     void
5590 win_setwidth(int width)
5591 {
5592     win_setwidth_win(width, curwin);
5593 }
5594 
5595     void
5596 win_setwidth_win(int width, win_T *wp)
5597 {
5598     // Always keep current window at least one column wide, even when
5599     // 'winminwidth' is zero.
5600     if (wp == curwin)
5601     {
5602 	if (width < p_wmw)
5603 	    width = p_wmw;
5604 	if (width == 0)
5605 	    width = 1;
5606     }
5607 
5608     frame_setwidth(wp->w_frame, width + wp->w_vsep_width);
5609 
5610     // recompute the window positions
5611     (void)win_comp_pos();
5612 
5613     redraw_all_later(NOT_VALID);
5614 }
5615 
5616 /*
5617  * Set the width of a frame to "width" and take care that all frames and
5618  * windows inside it are resized.  Also resize frames above and below if the
5619  * are in the same FR_ROW frame.
5620  *
5621  * Strategy is similar to frame_setheight().
5622  */
5623     static void
5624 frame_setwidth(frame_T *curfrp, int width)
5625 {
5626     int		room;		// total number of lines available
5627     int		take;		// number of lines taken from other windows
5628     int		run;
5629     frame_T	*frp;
5630     int		w;
5631     int		room_reserved;
5632 
5633     // If the width already is the desired value, nothing to do.
5634     if (curfrp->fr_width == width)
5635 	return;
5636 
5637     if (curfrp->fr_parent == NULL)
5638 	// topframe: can't change width
5639 	return;
5640 
5641     if (curfrp->fr_parent->fr_layout == FR_COL)
5642     {
5643 	// Column of frames: Also need to resize frames above and below of
5644 	// this one.  First check for the minimal width of these.
5645 	w = frame_minwidth(curfrp->fr_parent, NULL);
5646 	if (width < w)
5647 	    width = w;
5648 	frame_setwidth(curfrp->fr_parent, width);
5649     }
5650     else
5651     {
5652 	/*
5653 	 * Row of frames: try to change only frames in this row.
5654 	 *
5655 	 * Do this twice:
5656 	 * 1: compute room available, if it's not enough try resizing the
5657 	 *    containing frame.
5658 	 * 2: compute the room available and adjust the width to it.
5659 	 */
5660 	for (run = 1; run <= 2; ++run)
5661 	{
5662 	    room = 0;
5663 	    room_reserved = 0;
5664 	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
5665 	    {
5666 		if (frp != curfrp
5667 			&& frp->fr_win != NULL
5668 			&& frp->fr_win->w_p_wfw)
5669 		    room_reserved += frp->fr_width;
5670 		room += frp->fr_width;
5671 		if (frp != curfrp)
5672 		    room -= frame_minwidth(frp, NULL);
5673 	    }
5674 
5675 	    if (width <= room)
5676 		break;
5677 	    if (run == 2 || curfrp->fr_height >= ROWS_AVAIL)
5678 	    {
5679 		if (width > room)
5680 		    width = room;
5681 		break;
5682 	    }
5683 	    frame_setwidth(curfrp->fr_parent, width
5684 		 + frame_minwidth(curfrp->fr_parent, NOWIN) - (int)p_wmw - 1);
5685 	}
5686 
5687 	/*
5688 	 * Compute the number of lines we will take from others frames (can be
5689 	 * negative!).
5690 	 */
5691 	take = width - curfrp->fr_width;
5692 
5693 	// If there is not enough room, also reduce the width of a window
5694 	// with 'winfixwidth' set.
5695 	if (width > room - room_reserved)
5696 	    room_reserved = room - width;
5697 	// If there is only a 'winfixwidth' window and making the
5698 	// window smaller, need to make the other window narrower.
5699 	if (take < 0 && room - curfrp->fr_width < room_reserved)
5700 	    room_reserved = 0;
5701 
5702 	/*
5703 	 * set the current frame to the new width
5704 	 */
5705 	frame_new_width(curfrp, width, FALSE, FALSE);
5706 
5707 	/*
5708 	 * First take lines from the frames right of the current frame.  If
5709 	 * that is not enough, takes lines from frames left of the current
5710 	 * frame.
5711 	 */
5712 	for (run = 0; run < 2; ++run)
5713 	{
5714 	    if (run == 0)
5715 		frp = curfrp->fr_next;	// 1st run: start with next window
5716 	    else
5717 		frp = curfrp->fr_prev;	// 2nd run: start with prev window
5718 	    while (frp != NULL && take != 0)
5719 	    {
5720 		w = frame_minwidth(frp, NULL);
5721 		if (room_reserved > 0
5722 			&& frp->fr_win != NULL
5723 			&& frp->fr_win->w_p_wfw)
5724 		{
5725 		    if (room_reserved >= frp->fr_width)
5726 			room_reserved -= frp->fr_width;
5727 		    else
5728 		    {
5729 			if (frp->fr_width - room_reserved > take)
5730 			    room_reserved = frp->fr_width - take;
5731 			take -= frp->fr_width - room_reserved;
5732 			frame_new_width(frp, room_reserved, FALSE, FALSE);
5733 			room_reserved = 0;
5734 		    }
5735 		}
5736 		else
5737 		{
5738 		    if (frp->fr_width - take < w)
5739 		    {
5740 			take -= frp->fr_width - w;
5741 			frame_new_width(frp, w, FALSE, FALSE);
5742 		    }
5743 		    else
5744 		    {
5745 			frame_new_width(frp, frp->fr_width - take,
5746 								FALSE, FALSE);
5747 			take = 0;
5748 		    }
5749 		}
5750 		if (run == 0)
5751 		    frp = frp->fr_next;
5752 		else
5753 		    frp = frp->fr_prev;
5754 	    }
5755 	}
5756     }
5757 }
5758 
5759 /*
5760  * Check 'winminheight' for a valid value and reduce it if needed.
5761  */
5762     void
5763 win_setminheight(void)
5764 {
5765     int		room;
5766     int		needed;
5767     int		first = TRUE;
5768 
5769     // loop until there is a 'winminheight' that is possible
5770     while (p_wmh > 0)
5771     {
5772 	room = Rows - p_ch;
5773 	needed = frame_minheight(topframe, NULL);
5774 	if (room >= needed)
5775 	    break;
5776 	--p_wmh;
5777 	if (first)
5778 	{
5779 	    emsg(_(e_noroom));
5780 	    first = FALSE;
5781 	}
5782     }
5783 }
5784 
5785 /*
5786  * Check 'winminwidth' for a valid value and reduce it if needed.
5787  */
5788     void
5789 win_setminwidth(void)
5790 {
5791     int		room;
5792     int		needed;
5793     int		first = TRUE;
5794 
5795     // loop until there is a 'winminheight' that is possible
5796     while (p_wmw > 0)
5797     {
5798 	room = Columns;
5799 	needed = frame_minwidth(topframe, NULL);
5800 	if (room >= needed)
5801 	    break;
5802 	--p_wmw;
5803 	if (first)
5804 	{
5805 	    emsg(_(e_noroom));
5806 	    first = FALSE;
5807 	}
5808     }
5809 }
5810 
5811 /*
5812  * Status line of dragwin is dragged "offset" lines down (negative is up).
5813  */
5814     void
5815 win_drag_status_line(win_T *dragwin, int offset)
5816 {
5817     frame_T	*curfr;
5818     frame_T	*fr;
5819     int		room;
5820     int		row;
5821     int		up;	// if TRUE, drag status line up, otherwise down
5822     int		n;
5823 
5824     fr = dragwin->w_frame;
5825     curfr = fr;
5826     if (fr != topframe)		// more than one window
5827     {
5828 	fr = fr->fr_parent;
5829 	// When the parent frame is not a column of frames, its parent should
5830 	// be.
5831 	if (fr->fr_layout != FR_COL)
5832 	{
5833 	    curfr = fr;
5834 	    if (fr != topframe)	// only a row of windows, may drag statusline
5835 		fr = fr->fr_parent;
5836 	}
5837     }
5838 
5839     // If this is the last frame in a column, may want to resize the parent
5840     // frame instead (go two up to skip a row of frames).
5841     while (curfr != topframe && curfr->fr_next == NULL)
5842     {
5843 	if (fr != topframe)
5844 	    fr = fr->fr_parent;
5845 	curfr = fr;
5846 	if (fr != topframe)
5847 	    fr = fr->fr_parent;
5848     }
5849 
5850     if (offset < 0) // drag up
5851     {
5852 	up = TRUE;
5853 	offset = -offset;
5854 	// sum up the room of the current frame and above it
5855 	if (fr == curfr)
5856 	{
5857 	    // only one window
5858 	    room = fr->fr_height - frame_minheight(fr, NULL);
5859 	}
5860 	else
5861 	{
5862 	    room = 0;
5863 	    for (fr = fr->fr_child; ; fr = fr->fr_next)
5864 	    {
5865 		room += fr->fr_height - frame_minheight(fr, NULL);
5866 		if (fr == curfr)
5867 		    break;
5868 	    }
5869 	}
5870 	fr = curfr->fr_next;		// put fr at frame that grows
5871     }
5872     else    // drag down
5873     {
5874 	up = FALSE;
5875 	/*
5876 	 * Only dragging the last status line can reduce p_ch.
5877 	 */
5878 	room = Rows - cmdline_row;
5879 	if (curfr->fr_next == NULL)
5880 	    room -= 1;
5881 	else
5882 	    room -= p_ch;
5883 	if (room < 0)
5884 	    room = 0;
5885 	// sum up the room of frames below of the current one
5886 	FOR_ALL_FRAMES(fr, curfr->fr_next)
5887 	    room += fr->fr_height - frame_minheight(fr, NULL);
5888 	fr = curfr;			// put fr at window that grows
5889     }
5890 
5891     if (room < offset)		// Not enough room
5892 	offset = room;		// Move as far as we can
5893     if (offset <= 0)
5894 	return;
5895 
5896     /*
5897      * Grow frame fr by "offset" lines.
5898      * Doesn't happen when dragging the last status line up.
5899      */
5900     if (fr != NULL)
5901 	frame_new_height(fr, fr->fr_height + offset, up, FALSE);
5902 
5903     if (up)
5904 	fr = curfr;		// current frame gets smaller
5905     else
5906 	fr = curfr->fr_next;	// next frame gets smaller
5907 
5908     /*
5909      * Now make the other frames smaller.
5910      */
5911     while (fr != NULL && offset > 0)
5912     {
5913 	n = frame_minheight(fr, NULL);
5914 	if (fr->fr_height - offset <= n)
5915 	{
5916 	    offset -= fr->fr_height - n;
5917 	    frame_new_height(fr, n, !up, FALSE);
5918 	}
5919 	else
5920 	{
5921 	    frame_new_height(fr, fr->fr_height - offset, !up, FALSE);
5922 	    break;
5923 	}
5924 	if (up)
5925 	    fr = fr->fr_prev;
5926 	else
5927 	    fr = fr->fr_next;
5928     }
5929     row = win_comp_pos();
5930     screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5931     cmdline_row = row;
5932     p_ch = Rows - cmdline_row;
5933     if (p_ch < 1)
5934 	p_ch = 1;
5935     curtab->tp_ch_used = p_ch;
5936     redraw_all_later(SOME_VALID);
5937     showmode();
5938 }
5939 
5940 /*
5941  * Separator line of dragwin is dragged "offset" lines right (negative is left).
5942  */
5943     void
5944 win_drag_vsep_line(win_T *dragwin, int offset)
5945 {
5946     frame_T	*curfr;
5947     frame_T	*fr;
5948     int		room;
5949     int		left;	// if TRUE, drag separator line left, otherwise right
5950     int		n;
5951 
5952     fr = dragwin->w_frame;
5953     if (fr == topframe)		// only one window (cannot happen?)
5954 	return;
5955     curfr = fr;
5956     fr = fr->fr_parent;
5957     // When the parent frame is not a row of frames, its parent should be.
5958     if (fr->fr_layout != FR_ROW)
5959     {
5960 	if (fr == topframe)	// only a column of windows (cannot happen?)
5961 	    return;
5962 	curfr = fr;
5963 	fr = fr->fr_parent;
5964     }
5965 
5966     // If this is the last frame in a row, may want to resize a parent
5967     // frame instead.
5968     while (curfr->fr_next == NULL)
5969     {
5970 	if (fr == topframe)
5971 	    break;
5972 	curfr = fr;
5973 	fr = fr->fr_parent;
5974 	if (fr != topframe)
5975 	{
5976 	    curfr = fr;
5977 	    fr = fr->fr_parent;
5978 	}
5979     }
5980 
5981     if (offset < 0) // drag left
5982     {
5983 	left = TRUE;
5984 	offset = -offset;
5985 	// sum up the room of the current frame and left of it
5986 	room = 0;
5987 	for (fr = fr->fr_child; ; fr = fr->fr_next)
5988 	{
5989 	    room += fr->fr_width - frame_minwidth(fr, NULL);
5990 	    if (fr == curfr)
5991 		break;
5992 	}
5993 	fr = curfr->fr_next;		// put fr at frame that grows
5994     }
5995     else    // drag right
5996     {
5997 	left = FALSE;
5998 	// sum up the room of frames right of the current one
5999 	room = 0;
6000 	FOR_ALL_FRAMES(fr, curfr->fr_next)
6001 	    room += fr->fr_width - frame_minwidth(fr, NULL);
6002 	fr = curfr;			// put fr at window that grows
6003     }
6004 
6005     if (room < offset)		// Not enough room
6006 	offset = room;		// Move as far as we can
6007     if (offset <= 0)		// No room at all, quit.
6008 	return;
6009     if (fr == NULL)
6010 	return;			// Safety check, should not happen.
6011 
6012     // grow frame fr by offset lines
6013     frame_new_width(fr, fr->fr_width + offset, left, FALSE);
6014 
6015     // shrink other frames: current and at the left or at the right
6016     if (left)
6017 	fr = curfr;		// current frame gets smaller
6018     else
6019 	fr = curfr->fr_next;	// next frame gets smaller
6020 
6021     while (fr != NULL && offset > 0)
6022     {
6023 	n = frame_minwidth(fr, NULL);
6024 	if (fr->fr_width - offset <= n)
6025 	{
6026 	    offset -= fr->fr_width - n;
6027 	    frame_new_width(fr, n, !left, FALSE);
6028 	}
6029 	else
6030 	{
6031 	    frame_new_width(fr, fr->fr_width - offset, !left, FALSE);
6032 	    break;
6033 	}
6034 	if (left)
6035 	    fr = fr->fr_prev;
6036 	else
6037 	    fr = fr->fr_next;
6038     }
6039     (void)win_comp_pos();
6040     redraw_all_later(NOT_VALID);
6041 }
6042 
6043 #define FRACTION_MULT	16384L
6044 
6045 /*
6046  * Set wp->w_fraction for the current w_wrow and w_height.
6047  * Has no effect when the window is less than two lines.
6048  */
6049     void
6050 set_fraction(win_T *wp)
6051 {
6052     if (wp->w_height > 1)
6053 	// When cursor is in the first line the percentage is computed as if
6054 	// it's halfway that line.  Thus with two lines it is 25%, with three
6055 	// lines 17%, etc.  Similarly for the last line: 75%, 83%, etc.
6056 	wp->w_fraction = ((long)wp->w_wrow * FRACTION_MULT
6057 				     + FRACTION_MULT / 2) / (long)wp->w_height;
6058 }
6059 
6060 /*
6061  * Set the height of a window.
6062  * "height" excludes any window toolbar.
6063  * This takes care of the things inside the window, not what happens to the
6064  * window position, the frame or to other windows.
6065  */
6066     void
6067 win_new_height(win_T *wp, int height)
6068 {
6069     int		prev_height = wp->w_height;
6070 
6071     // Don't want a negative height.  Happens when splitting a tiny window.
6072     // Will equalize heights soon to fix it.
6073     if (height < 0)
6074 	height = 0;
6075     if (wp->w_height == height)
6076 	return;	    // nothing to do
6077 
6078     if (wp->w_height > 0)
6079     {
6080 	if (wp == curwin)
6081 	    // w_wrow needs to be valid. When setting 'laststatus' this may
6082 	    // call win_new_height() recursively.
6083 	    validate_cursor();
6084 	if (wp->w_height != prev_height)
6085 	    return;  // Recursive call already changed the size, bail out here
6086 		     //	to avoid the following to mess things up.
6087 	if (wp->w_wrow != wp->w_prev_fraction_row)
6088 	    set_fraction(wp);
6089     }
6090 
6091     wp->w_height = height;
6092     wp->w_skipcol = 0;
6093 
6094     // There is no point in adjusting the scroll position when exiting.  Some
6095     // values might be invalid.
6096     if (!exiting)
6097 	scroll_to_fraction(wp, prev_height);
6098 }
6099 
6100     void
6101 scroll_to_fraction(win_T *wp, int prev_height)
6102 {
6103     linenr_T	lnum;
6104     int		sline, line_size;
6105     int		height = wp->w_height;
6106 
6107     // Don't change w_topline in any of these cases:
6108     // - window height is 0
6109     // - 'scrollbind' is set and this isn't the current window
6110     // - window height is sufficient to display the whole buffer and first line
6111     //   is visible.
6112     if (height > 0
6113         && (!wp->w_p_scb || wp == curwin)
6114         && (height < wp->w_buffer->b_ml.ml_line_count || wp->w_topline > 1))
6115     {
6116 	/*
6117 	 * Find a value for w_topline that shows the cursor at the same
6118 	 * relative position in the window as before (more or less).
6119 	 */
6120 	lnum = wp->w_cursor.lnum;
6121 	if (lnum < 1)		// can happen when starting up
6122 	    lnum = 1;
6123 	wp->w_wrow = ((long)wp->w_fraction * (long)height - 1L)
6124 							       / FRACTION_MULT;
6125 	line_size = plines_win_col(wp, lnum, (long)(wp->w_cursor.col)) - 1;
6126 	sline = wp->w_wrow - line_size;
6127 
6128 	if (sline >= 0)
6129 	{
6130 	    // Make sure the whole cursor line is visible, if possible.
6131 	    int rows = plines_win(wp, lnum, FALSE);
6132 
6133 	    if (sline > wp->w_height - rows)
6134 	    {
6135 		sline = wp->w_height - rows;
6136 		wp->w_wrow -= rows - line_size;
6137 	    }
6138 	}
6139 
6140 	if (sline < 0)
6141 	{
6142 	    /*
6143 	     * Cursor line would go off top of screen if w_wrow was this high.
6144 	     * Make cursor line the first line in the window.  If not enough
6145 	     * room use w_skipcol;
6146 	     */
6147 	    wp->w_wrow = line_size;
6148 	    if (wp->w_wrow >= wp->w_height
6149 				       && (wp->w_width - win_col_off(wp)) > 0)
6150 	    {
6151 		wp->w_skipcol += wp->w_width - win_col_off(wp);
6152 		--wp->w_wrow;
6153 		while (wp->w_wrow >= wp->w_height)
6154 		{
6155 		    wp->w_skipcol += wp->w_width - win_col_off(wp)
6156 							   + win_col_off2(wp);
6157 		    --wp->w_wrow;
6158 		}
6159 	    }
6160 	}
6161 	else if (sline > 0)
6162 	{
6163 	    while (sline > 0 && lnum > 1)
6164 	    {
6165 #ifdef FEAT_FOLDING
6166 		hasFoldingWin(wp, lnum, &lnum, NULL, TRUE, NULL);
6167 		if (lnum == 1)
6168 		{
6169 		    // first line in buffer is folded
6170 		    line_size = 1;
6171 		    --sline;
6172 		    break;
6173 		}
6174 #endif
6175 		--lnum;
6176 #ifdef FEAT_DIFF
6177 		if (lnum == wp->w_topline)
6178 		    line_size = plines_win_nofill(wp, lnum, TRUE)
6179 							      + wp->w_topfill;
6180 		else
6181 #endif
6182 		    line_size = plines_win(wp, lnum, TRUE);
6183 		sline -= line_size;
6184 	    }
6185 
6186 	    if (sline < 0)
6187 	    {
6188 		/*
6189 		 * Line we want at top would go off top of screen.  Use next
6190 		 * line instead.
6191 		 */
6192 #ifdef FEAT_FOLDING
6193 		hasFoldingWin(wp, lnum, NULL, &lnum, TRUE, NULL);
6194 #endif
6195 		lnum++;
6196 		wp->w_wrow -= line_size + sline;
6197 	    }
6198 	    else if (sline > 0)
6199 	    {
6200 		// First line of file reached, use that as topline.
6201 		lnum = 1;
6202 		wp->w_wrow -= sline;
6203 	    }
6204 	}
6205 	set_topline(wp, lnum);
6206     }
6207 
6208     if (wp == curwin)
6209     {
6210 	if (get_scrolloff_value())
6211 	    update_topline();
6212 	curs_columns(FALSE);	// validate w_wrow
6213     }
6214     if (prev_height > 0)
6215 	wp->w_prev_fraction_row = wp->w_wrow;
6216 
6217     win_comp_scroll(wp);
6218     redraw_win_later(wp, SOME_VALID);
6219     wp->w_redr_status = TRUE;
6220     invalidate_botline_win(wp);
6221 }
6222 
6223 /*
6224  * Set the width of a window.
6225  */
6226     void
6227 win_new_width(win_T *wp, int width)
6228 {
6229     wp->w_width = width;
6230     wp->w_lines_valid = 0;
6231     changed_line_abv_curs_win(wp);
6232     invalidate_botline_win(wp);
6233     if (wp == curwin)
6234     {
6235 	update_topline();
6236 	curs_columns(TRUE);	// validate w_wrow
6237     }
6238     redraw_win_later(wp, NOT_VALID);
6239     wp->w_redr_status = TRUE;
6240 }
6241 
6242     void
6243 win_comp_scroll(win_T *wp)
6244 {
6245     wp->w_p_scr = ((unsigned)wp->w_height >> 1);
6246     if (wp->w_p_scr == 0)
6247 	wp->w_p_scr = 1;
6248 }
6249 
6250 /*
6251  * command_height: called whenever p_ch has been changed
6252  */
6253     void
6254 command_height(void)
6255 {
6256     int		h;
6257     frame_T	*frp;
6258     int		old_p_ch = curtab->tp_ch_used;
6259 
6260     // Use the value of p_ch that we remembered.  This is needed for when the
6261     // GUI starts up, we can't be sure in what order things happen.  And when
6262     // p_ch was changed in another tab page.
6263     curtab->tp_ch_used = p_ch;
6264 
6265     // Find bottom frame with width of screen.
6266     frp = lastwin->w_frame;
6267     while (frp->fr_width != Columns && frp->fr_parent != NULL)
6268 	frp = frp->fr_parent;
6269 
6270     // Avoid changing the height of a window with 'winfixheight' set.
6271     while (frp->fr_prev != NULL && frp->fr_layout == FR_LEAF
6272 						      && frp->fr_win->w_p_wfh)
6273 	frp = frp->fr_prev;
6274 
6275     if (starting != NO_SCREEN)
6276     {
6277 	cmdline_row = Rows - p_ch;
6278 
6279 	if (p_ch > old_p_ch)		    // p_ch got bigger
6280 	{
6281 	    while (p_ch > old_p_ch)
6282 	    {
6283 		if (frp == NULL)
6284 		{
6285 		    emsg(_(e_noroom));
6286 		    p_ch = old_p_ch;
6287 		    curtab->tp_ch_used = p_ch;
6288 		    cmdline_row = Rows - p_ch;
6289 		    break;
6290 		}
6291 		h = frp->fr_height - frame_minheight(frp, NULL);
6292 		if (h > p_ch - old_p_ch)
6293 		    h = p_ch - old_p_ch;
6294 		old_p_ch += h;
6295 		frame_add_height(frp, -h);
6296 		frp = frp->fr_prev;
6297 	    }
6298 
6299 	    // Recompute window positions.
6300 	    (void)win_comp_pos();
6301 
6302 	    // clear the lines added to cmdline
6303 	    if (full_screen)
6304 		screen_fill((int)(cmdline_row), (int)Rows, 0,
6305 						   (int)Columns, ' ', ' ', 0);
6306 	    msg_row = cmdline_row;
6307 	    redraw_cmdline = TRUE;
6308 	    return;
6309 	}
6310 
6311 	if (msg_row < cmdline_row)
6312 	    msg_row = cmdline_row;
6313 	redraw_cmdline = TRUE;
6314     }
6315     frame_add_height(frp, (int)(old_p_ch - p_ch));
6316 
6317     // Recompute window positions.
6318     if (frp != lastwin->w_frame)
6319 	(void)win_comp_pos();
6320 }
6321 
6322 /*
6323  * Resize frame "frp" to be "n" lines higher (negative for less high).
6324  * Also resize the frames it is contained in.
6325  */
6326     static void
6327 frame_add_height(frame_T *frp, int n)
6328 {
6329     frame_new_height(frp, frp->fr_height + n, FALSE, FALSE);
6330     for (;;)
6331     {
6332 	frp = frp->fr_parent;
6333 	if (frp == NULL)
6334 	    break;
6335 	frp->fr_height += n;
6336     }
6337 }
6338 
6339 /*
6340  * Add or remove a status line for the bottom window(s), according to the
6341  * value of 'laststatus'.
6342  */
6343     void
6344 last_status(
6345     int		morewin)	// pretend there are two or more windows
6346 {
6347     // Don't make a difference between horizontal or vertical split.
6348     last_status_rec(topframe, (p_ls == 2
6349 			  || (p_ls == 1 && (morewin || !ONE_WINDOW))));
6350 }
6351 
6352     static void
6353 last_status_rec(frame_T *fr, int statusline)
6354 {
6355     frame_T	*fp;
6356     win_T	*wp;
6357 
6358     if (fr->fr_layout == FR_LEAF)
6359     {
6360 	wp = fr->fr_win;
6361 	if (wp->w_status_height != 0 && !statusline)
6362 	{
6363 	    // remove status line
6364 	    win_new_height(wp, wp->w_height + 1);
6365 	    wp->w_status_height = 0;
6366 	    comp_col();
6367 	}
6368 	else if (wp->w_status_height == 0 && statusline)
6369 	{
6370 	    // Find a frame to take a line from.
6371 	    fp = fr;
6372 	    while (fp->fr_height <= frame_minheight(fp, NULL))
6373 	    {
6374 		if (fp == topframe)
6375 		{
6376 		    emsg(_(e_noroom));
6377 		    return;
6378 		}
6379 		// In a column of frames: go to frame above.  If already at
6380 		// the top or in a row of frames: go to parent.
6381 		if (fp->fr_parent->fr_layout == FR_COL && fp->fr_prev != NULL)
6382 		    fp = fp->fr_prev;
6383 		else
6384 		    fp = fp->fr_parent;
6385 	    }
6386 	    wp->w_status_height = 1;
6387 	    if (fp != fr)
6388 	    {
6389 		frame_new_height(fp, fp->fr_height - 1, FALSE, FALSE);
6390 		frame_fix_height(wp);
6391 		(void)win_comp_pos();
6392 	    }
6393 	    else
6394 		win_new_height(wp, wp->w_height - 1);
6395 	    comp_col();
6396 	    redraw_all_later(SOME_VALID);
6397 	}
6398     }
6399     else if (fr->fr_layout == FR_ROW)
6400     {
6401 	// vertically split windows, set status line for each one
6402 	FOR_ALL_FRAMES(fp, fr->fr_child)
6403 	    last_status_rec(fp, statusline);
6404     }
6405     else
6406     {
6407 	// horizontally split window, set status line for last one
6408 	for (fp = fr->fr_child; fp->fr_next != NULL; fp = fp->fr_next)
6409 	    ;
6410 	last_status_rec(fp, statusline);
6411     }
6412 }
6413 
6414 /*
6415  * Return the number of lines used by the tab page line.
6416  */
6417     int
6418 tabline_height(void)
6419 {
6420 #ifdef FEAT_GUI_TABLINE
6421     // When the GUI has the tabline then this always returns zero.
6422     if (gui_use_tabline())
6423 	return 0;
6424 #endif
6425     switch (p_stal)
6426     {
6427 	case 0: return 0;
6428 	case 1: return (first_tabpage->tp_next == NULL) ? 0 : 1;
6429     }
6430     return 1;
6431 }
6432 
6433 /*
6434  * Return the minimal number of rows that is needed on the screen to display
6435  * the current number of windows.
6436  */
6437     int
6438 min_rows(void)
6439 {
6440     int		total;
6441     tabpage_T	*tp;
6442     int		n;
6443 
6444     if (firstwin == NULL)	// not initialized yet
6445 	return MIN_LINES;
6446 
6447     total = 0;
6448     FOR_ALL_TABPAGES(tp)
6449     {
6450 	n = frame_minheight(tp->tp_topframe, NULL);
6451 	if (total < n)
6452 	    total = n;
6453     }
6454     total += tabline_height();
6455     total += 1;		// count the room for the command line
6456     return total;
6457 }
6458 
6459 /*
6460  * Return TRUE if there is only one window and only one tab page, not
6461  * counting a help or preview window, unless it is the current window.
6462  * Does not count unlisted windows.
6463  */
6464     int
6465 only_one_window(void)
6466 {
6467     int		count = 0;
6468     win_T	*wp;
6469 
6470 #if defined(FEAT_PROP_POPUP)
6471     // If the current window is a popup then there always is another window.
6472     if (popup_is_popup(curwin))
6473 	return FALSE;
6474 #endif
6475 
6476     // If there is another tab page there always is another window.
6477     if (first_tabpage->tp_next != NULL)
6478 	return FALSE;
6479 
6480     FOR_ALL_WINDOWS(wp)
6481 	if (wp->w_buffer != NULL
6482 		&& (!((bt_help(wp->w_buffer) && !bt_help(curbuf))
6483 # ifdef FEAT_QUICKFIX
6484 		    || wp->w_p_pvw
6485 # endif
6486 	     ) || wp == curwin) && wp != aucmd_win)
6487 	    ++count;
6488     return (count <= 1);
6489 }
6490 
6491 /*
6492  * Correct the cursor line number in other windows.  Used after changing the
6493  * current buffer, and before applying autocommands.
6494  * When "do_curwin" is TRUE, also check current window.
6495  */
6496     void
6497 check_lnums(int do_curwin)
6498 {
6499     win_T	*wp;
6500     tabpage_T	*tp;
6501 
6502     FOR_ALL_TAB_WINDOWS(tp, wp)
6503 	if ((do_curwin || wp != curwin) && wp->w_buffer == curbuf)
6504 	{
6505 	    // save the original cursor position and topline
6506 	    wp->w_save_cursor.w_cursor_save = wp->w_cursor;
6507 	    wp->w_save_cursor.w_topline_save = wp->w_topline;
6508 
6509 	    if (wp->w_cursor.lnum > curbuf->b_ml.ml_line_count)
6510 		wp->w_cursor.lnum = curbuf->b_ml.ml_line_count;
6511 	    if (wp->w_topline > curbuf->b_ml.ml_line_count)
6512 		wp->w_topline = curbuf->b_ml.ml_line_count;
6513 
6514 	    // save the corrected cursor position and topline
6515 	    wp->w_save_cursor.w_cursor_corr = wp->w_cursor;
6516 	    wp->w_save_cursor.w_topline_corr = wp->w_topline;
6517 	}
6518 }
6519 
6520 /*
6521  * Reset cursor and topline to its stored values from check_lnums().
6522  * check_lnums() must have been called first!
6523  */
6524     void
6525 reset_lnums()
6526 {
6527     win_T	*wp;
6528     tabpage_T	*tp;
6529 
6530     FOR_ALL_TAB_WINDOWS(tp, wp)
6531 	if (wp->w_buffer == curbuf)
6532 	{
6533 	    // Restore the value if the autocommand didn't change it.
6534 	    if (EQUAL_POS(wp->w_save_cursor.w_cursor_corr, wp->w_cursor))
6535 		wp->w_cursor = wp->w_save_cursor.w_cursor_save;
6536 	    if (wp->w_save_cursor.w_topline_corr == wp->w_topline)
6537 		wp->w_topline = wp->w_save_cursor.w_topline_save;
6538 	}
6539 }
6540 
6541 /*
6542  * A snapshot of the window sizes, to restore them after closing the help
6543  * window.
6544  * Only these fields are used:
6545  * fr_layout
6546  * fr_width
6547  * fr_height
6548  * fr_next
6549  * fr_child
6550  * fr_win (only valid for the old curwin, NULL otherwise)
6551  */
6552 
6553 /*
6554  * Create a snapshot of the current frame sizes.
6555  */
6556     void
6557 make_snapshot(int idx)
6558 {
6559     clear_snapshot(curtab, idx);
6560     make_snapshot_rec(topframe, &curtab->tp_snapshot[idx]);
6561 }
6562 
6563     static void
6564 make_snapshot_rec(frame_T *fr, frame_T **frp)
6565 {
6566     *frp = ALLOC_CLEAR_ONE(frame_T);
6567     if (*frp == NULL)
6568 	return;
6569     (*frp)->fr_layout = fr->fr_layout;
6570     (*frp)->fr_width = fr->fr_width;
6571     (*frp)->fr_height = fr->fr_height;
6572     if (fr->fr_next != NULL)
6573 	make_snapshot_rec(fr->fr_next, &((*frp)->fr_next));
6574     if (fr->fr_child != NULL)
6575 	make_snapshot_rec(fr->fr_child, &((*frp)->fr_child));
6576     if (fr->fr_layout == FR_LEAF && fr->fr_win == curwin)
6577 	(*frp)->fr_win = curwin;
6578 }
6579 
6580 /*
6581  * Remove any existing snapshot.
6582  */
6583     static void
6584 clear_snapshot(tabpage_T *tp, int idx)
6585 {
6586     clear_snapshot_rec(tp->tp_snapshot[idx]);
6587     tp->tp_snapshot[idx] = NULL;
6588 }
6589 
6590     static void
6591 clear_snapshot_rec(frame_T *fr)
6592 {
6593     if (fr != NULL)
6594     {
6595 	clear_snapshot_rec(fr->fr_next);
6596 	clear_snapshot_rec(fr->fr_child);
6597 	vim_free(fr);
6598     }
6599 }
6600 
6601 /*
6602  * Restore a previously created snapshot, if there is any.
6603  * This is only done if the screen size didn't change and the window layout is
6604  * still the same.
6605  */
6606     void
6607 restore_snapshot(
6608     int		idx,
6609     int		close_curwin)	    // closing current window
6610 {
6611     win_T	*wp;
6612 
6613     if (curtab->tp_snapshot[idx] != NULL
6614 	    && curtab->tp_snapshot[idx]->fr_width == topframe->fr_width
6615 	    && curtab->tp_snapshot[idx]->fr_height == topframe->fr_height
6616 	    && check_snapshot_rec(curtab->tp_snapshot[idx], topframe) == OK)
6617     {
6618 	wp = restore_snapshot_rec(curtab->tp_snapshot[idx], topframe);
6619 	win_comp_pos();
6620 	if (wp != NULL && close_curwin)
6621 	    win_goto(wp);
6622 	redraw_all_later(NOT_VALID);
6623     }
6624     clear_snapshot(curtab, idx);
6625 }
6626 
6627 /*
6628  * Check if frames "sn" and "fr" have the same layout, same following frames
6629  * and same children.  And the window pointer is valid.
6630  */
6631     static int
6632 check_snapshot_rec(frame_T *sn, frame_T *fr)
6633 {
6634     if (sn->fr_layout != fr->fr_layout
6635 	    || (sn->fr_next == NULL) != (fr->fr_next == NULL)
6636 	    || (sn->fr_child == NULL) != (fr->fr_child == NULL)
6637 	    || (sn->fr_next != NULL
6638 		&& check_snapshot_rec(sn->fr_next, fr->fr_next) == FAIL)
6639 	    || (sn->fr_child != NULL
6640 		&& check_snapshot_rec(sn->fr_child, fr->fr_child) == FAIL)
6641 	    || (sn->fr_win != NULL && !win_valid(sn->fr_win)))
6642 	return FAIL;
6643     return OK;
6644 }
6645 
6646 /*
6647  * Copy the size of snapshot frame "sn" to frame "fr".  Do the same for all
6648  * following frames and children.
6649  * Returns a pointer to the old current window, or NULL.
6650  */
6651     static win_T *
6652 restore_snapshot_rec(frame_T *sn, frame_T *fr)
6653 {
6654     win_T	*wp = NULL;
6655     win_T	*wp2;
6656 
6657     fr->fr_height = sn->fr_height;
6658     fr->fr_width = sn->fr_width;
6659     if (fr->fr_layout == FR_LEAF)
6660     {
6661 	frame_new_height(fr, fr->fr_height, FALSE, FALSE);
6662 	frame_new_width(fr, fr->fr_width, FALSE, FALSE);
6663 	wp = sn->fr_win;
6664     }
6665     if (sn->fr_next != NULL)
6666     {
6667 	wp2 = restore_snapshot_rec(sn->fr_next, fr->fr_next);
6668 	if (wp2 != NULL)
6669 	    wp = wp2;
6670     }
6671     if (sn->fr_child != NULL)
6672     {
6673 	wp2 = restore_snapshot_rec(sn->fr_child, fr->fr_child);
6674 	if (wp2 != NULL)
6675 	    wp = wp2;
6676     }
6677     return wp;
6678 }
6679 
6680 #if defined(FEAT_GUI) || defined(PROTO)
6681 /*
6682  * Return TRUE if there is any vertically split window.
6683  */
6684     int
6685 win_hasvertsplit(void)
6686 {
6687     frame_T	*fr;
6688 
6689     if (topframe->fr_layout == FR_ROW)
6690 	return TRUE;
6691 
6692     if (topframe->fr_layout == FR_COL)
6693 	FOR_ALL_FRAMES(fr, topframe->fr_child)
6694 	    if (fr->fr_layout == FR_ROW)
6695 		return TRUE;
6696 
6697     return FALSE;
6698 }
6699 #endif
6700 
6701 #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) || defined(PROTO)
6702     int
6703 get_win_number(win_T *wp, win_T *first_win)
6704 {
6705     int		i = 1;
6706     win_T	*w;
6707 
6708     for (w = first_win; w != NULL && w != wp; w = W_NEXT(w))
6709 	++i;
6710 
6711     if (w == NULL)
6712 	return 0;
6713     else
6714 	return i;
6715 }
6716 
6717     int
6718 get_tab_number(tabpage_T *tp UNUSED)
6719 {
6720     int		i = 1;
6721     tabpage_T	*t;
6722 
6723     for (t = first_tabpage; t != NULL && t != tp; t = t->tp_next)
6724 	++i;
6725 
6726     if (t == NULL)
6727 	return 0;
6728     else
6729 	return i;
6730 }
6731 #endif
6732 
6733 /*
6734  * Return TRUE if "topfrp" and its children are at the right height.
6735  */
6736     static int
6737 frame_check_height(frame_T *topfrp, int height)
6738 {
6739     frame_T *frp;
6740 
6741     if (topfrp->fr_height != height)
6742 	return FALSE;
6743 
6744     if (topfrp->fr_layout == FR_ROW)
6745 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
6746 	    if (frp->fr_height != height)
6747 		return FALSE;
6748 
6749     return TRUE;
6750 }
6751 
6752 /*
6753  * Return TRUE if "topfrp" and its children are at the right width.
6754  */
6755     static int
6756 frame_check_width(frame_T *topfrp, int width)
6757 {
6758     frame_T *frp;
6759 
6760     if (topfrp->fr_width != width)
6761 	return FALSE;
6762 
6763     if (topfrp->fr_layout == FR_COL)
6764 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
6765 	    if (frp->fr_width != width)
6766 		return FALSE;
6767 
6768     return TRUE;
6769 }
6770 
6771 #if defined(FEAT_SYN_HL) || defined(PROTO)
6772 /*
6773  * Simple int comparison function for use with qsort()
6774  */
6775     static int
6776 int_cmp(const void *a, const void *b)
6777 {
6778     return *(const int *)a - *(const int *)b;
6779 }
6780 
6781 /*
6782  * Handle setting 'colorcolumn' or 'textwidth' in window "wp".
6783  * Returns error message, NULL if it's OK.
6784  */
6785     char *
6786 check_colorcolumn(win_T *wp)
6787 {
6788     char_u	*s;
6789     int		col;
6790     int		count = 0;
6791     int		color_cols[256];
6792     int		i;
6793     int		j = 0;
6794 
6795     if (wp->w_buffer == NULL)
6796 	return NULL;  // buffer was closed
6797 
6798     for (s = wp->w_p_cc; *s != NUL && count < 255;)
6799     {
6800 	if (*s == '-' || *s == '+')
6801 	{
6802 	    // -N and +N: add to 'textwidth'
6803 	    col = (*s == '-') ? -1 : 1;
6804 	    ++s;
6805 	    if (!VIM_ISDIGIT(*s))
6806 		return e_invarg;
6807 	    col = col * getdigits(&s);
6808 	    if (wp->w_buffer->b_p_tw == 0)
6809 		goto skip;  // 'textwidth' not set, skip this item
6810 	    col += wp->w_buffer->b_p_tw;
6811 	    if (col < 0)
6812 		goto skip;
6813 	}
6814 	else if (VIM_ISDIGIT(*s))
6815 	    col = getdigits(&s);
6816 	else
6817 	    return e_invarg;
6818 	color_cols[count++] = col - 1;  // 1-based to 0-based
6819 skip:
6820 	if (*s == NUL)
6821 	    break;
6822 	if (*s != ',')
6823 	    return e_invarg;
6824 	if (*++s == NUL)
6825 	    return e_invarg;  // illegal trailing comma as in "set cc=80,"
6826     }
6827 
6828     vim_free(wp->w_p_cc_cols);
6829     if (count == 0)
6830 	wp->w_p_cc_cols = NULL;
6831     else
6832     {
6833 	wp->w_p_cc_cols = ALLOC_MULT(int, count + 1);
6834 	if (wp->w_p_cc_cols != NULL)
6835 	{
6836 	    // sort the columns for faster usage on screen redraw inside
6837 	    // win_line()
6838 	    qsort(color_cols, count, sizeof(int), int_cmp);
6839 
6840 	    for (i = 0; i < count; ++i)
6841 		// skip duplicates
6842 		if (j == 0 || wp->w_p_cc_cols[j - 1] != color_cols[i])
6843 		    wp->w_p_cc_cols[j++] = color_cols[i];
6844 	    wp->w_p_cc_cols[j] = -1;  // end marker
6845 	}
6846     }
6847 
6848     return NULL;  // no error
6849 }
6850 #endif
6851