xref: /vim-8.2.3635/src/window.c (revision 040f975f)
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 		    case TAB:	    // CTRL-W g<Tab>: go to last used tab page
631 			if (goto_tabpage_lastused() == FAIL)
632 			    beep_flush();
633 			break;
634 
635 		    default:
636 			beep_flush();
637 			break;
638 		}
639 		break;
640 
641     default:	beep_flush();
642 		break;
643     }
644 }
645 
646 /*
647  * Figure out the address type for ":wincmd".
648  */
649     void
650 get_wincmd_addr_type(char_u *arg, exarg_T *eap)
651 {
652     switch (*arg)
653     {
654     case 'S':
655     case Ctrl_S:
656     case 's':
657     case Ctrl_N:
658     case 'n':
659     case 'j':
660     case Ctrl_J:
661     case 'k':
662     case Ctrl_K:
663     case 'T':
664     case Ctrl_R:
665     case 'r':
666     case 'R':
667     case 'K':
668     case 'J':
669     case '+':
670     case '-':
671     case Ctrl__:
672     case '_':
673     case '|':
674     case ']':
675     case Ctrl_RSB:
676     case 'g':
677     case Ctrl_G:
678     case Ctrl_V:
679     case 'v':
680     case 'h':
681     case Ctrl_H:
682     case 'l':
683     case Ctrl_L:
684     case 'H':
685     case 'L':
686     case '>':
687     case '<':
688 #if defined(FEAT_QUICKFIX)
689     case '}':
690 #endif
691 #ifdef FEAT_SEARCHPATH
692     case 'f':
693     case 'F':
694     case Ctrl_F:
695 #endif
696 #ifdef FEAT_FIND_ID
697     case 'i':
698     case Ctrl_I:
699     case 'd':
700     case Ctrl_D:
701 #endif
702 		// window size or any count
703 		eap->addr_type = ADDR_OTHER;
704 		break;
705 
706     case Ctrl_HAT:
707     case '^':
708 		// buffer number
709 		eap->addr_type = ADDR_BUFFERS;
710 		break;
711 
712     case Ctrl_Q:
713     case 'q':
714     case Ctrl_C:
715     case 'c':
716     case Ctrl_O:
717     case 'o':
718     case Ctrl_W:
719     case 'w':
720     case 'W':
721     case 'x':
722     case Ctrl_X:
723 		// window number
724 		eap->addr_type = ADDR_WINDOWS;
725 		break;
726 
727 #if defined(FEAT_QUICKFIX)
728     case Ctrl_Z:
729     case 'z':
730     case 'P':
731 #endif
732     case 't':
733     case Ctrl_T:
734     case 'b':
735     case Ctrl_B:
736     case 'p':
737     case Ctrl_P:
738     case '=':
739     case CAR:
740 		// no count
741 		eap->addr_type = ADDR_NONE;
742 		break;
743     }
744 }
745 
746     static void
747 cmd_with_count(
748     char	*cmd,
749     char_u	*bufp,
750     size_t	bufsize,
751     long	Prenum)
752 {
753     size_t	len = STRLEN(cmd);
754 
755     STRCPY(bufp, cmd);
756     if (Prenum > 0)
757 	vim_snprintf((char *)bufp + len, bufsize - len, "%ld", Prenum);
758 }
759 
760 /*
761  * If "split_disallowed" is set given an error and return FAIL.
762  * Otherwise return OK.
763  */
764     static int
765 check_split_disallowed()
766 {
767     if (split_disallowed > 0)
768     {
769 	emsg(_("E242: Can't split a window while closing another"));
770 	return FAIL;
771     }
772     return OK;
773 }
774 
775 /*
776  * split the current window, implements CTRL-W s and :split
777  *
778  * "size" is the height or width for the new window, 0 to use half of current
779  * height or width.
780  *
781  * "flags":
782  * WSP_ROOM: require enough room for new window
783  * WSP_VERT: vertical split.
784  * WSP_TOP:  open window at the top-left of the shell (help window).
785  * WSP_BOT:  open window at the bottom-right of the shell (quickfix window).
786  * WSP_HELP: creating the help window, keep layout snapshot
787  *
788  * return FAIL for failure, OK otherwise
789  */
790     int
791 win_split(int size, int flags)
792 {
793     if (ERROR_IF_ANY_POPUP_WINDOW)
794 	return FAIL;
795 
796     // When the ":tab" modifier was used open a new tab page instead.
797     if (may_open_tabpage() == OK)
798 	return OK;
799 
800     // Add flags from ":vertical", ":topleft" and ":botright".
801     flags |= cmdmod.split;
802     if ((flags & WSP_TOP) && (flags & WSP_BOT))
803     {
804 	emsg(_("E442: Can't split topleft and botright at the same time"));
805 	return FAIL;
806     }
807     if (check_split_disallowed() == FAIL)
808 	return FAIL;
809 
810     // When creating the help window make a snapshot of the window layout.
811     // Otherwise clear the snapshot, it's now invalid.
812     if (flags & WSP_HELP)
813 	make_snapshot(SNAP_HELP_IDX);
814     else
815 	clear_snapshot(curtab, SNAP_HELP_IDX);
816 
817     return win_split_ins(size, flags, NULL, 0);
818 }
819 
820 /*
821  * When "new_wp" is NULL: split the current window in two.
822  * When "new_wp" is not NULL: insert this window at the far
823  * top/left/right/bottom.
824  * return FAIL for failure, OK otherwise
825  */
826     int
827 win_split_ins(
828     int		size,
829     int		flags,
830     win_T	*new_wp,
831     int		dir)
832 {
833     win_T	*wp = new_wp;
834     win_T	*oldwin;
835     int		new_size = size;
836     int		i;
837     int		need_status = 0;
838     int		do_equal = FALSE;
839     int		needed;
840     int		available;
841     int		oldwin_height = 0;
842     int		layout;
843     frame_T	*frp, *curfrp, *frp2, *prevfrp;
844     int		before;
845     int		minheight;
846     int		wmh1;
847     int		did_set_fraction = FALSE;
848 
849     if (flags & WSP_TOP)
850 	oldwin = firstwin;
851     else if (flags & WSP_BOT)
852 	oldwin = lastwin;
853     else
854 	oldwin = curwin;
855 
856     // add a status line when p_ls == 1 and splitting the first window
857     if (ONE_WINDOW && p_ls == 1 && oldwin->w_status_height == 0)
858     {
859 	if (VISIBLE_HEIGHT(oldwin) <= p_wmh && new_wp == NULL)
860 	{
861 	    emsg(_(e_noroom));
862 	    return FAIL;
863 	}
864 	need_status = STATUS_HEIGHT;
865     }
866 
867 #ifdef FEAT_GUI
868     // May be needed for the scrollbars that are going to change.
869     if (gui.in_use)
870 	out_flush();
871 #endif
872 
873     if (flags & WSP_VERT)
874     {
875 	int	wmw1;
876 	int	minwidth;
877 
878 	layout = FR_ROW;
879 
880 	/*
881 	 * Check if we are able to split the current window and compute its
882 	 * width.
883 	 */
884 	// Current window requires at least 1 space.
885 	wmw1 = (p_wmw == 0 ? 1 : p_wmw);
886 	needed = wmw1 + 1;
887 	if (flags & WSP_ROOM)
888 	    needed += p_wiw - wmw1;
889 	if (flags & (WSP_BOT | WSP_TOP))
890 	{
891 	    minwidth = frame_minwidth(topframe, NOWIN);
892 	    available = topframe->fr_width;
893 	    needed += minwidth;
894 	}
895 	else if (p_ea)
896 	{
897 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
898 	    prevfrp = oldwin->w_frame;
899 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
900 							frp = frp->fr_parent)
901 	    {
902 		if (frp->fr_layout == FR_ROW)
903 		    FOR_ALL_FRAMES(frp2, frp->fr_child)
904 			if (frp2 != prevfrp)
905 			    minwidth += frame_minwidth(frp2, NOWIN);
906 		prevfrp = frp;
907 	    }
908 	    available = topframe->fr_width;
909 	    needed += minwidth;
910 	}
911 	else
912 	{
913 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
914 	    available = oldwin->w_frame->fr_width;
915 	    needed += minwidth;
916 	}
917 	if (available < needed && new_wp == NULL)
918 	{
919 	    emsg(_(e_noroom));
920 	    return FAIL;
921 	}
922 	if (new_size == 0)
923 	    new_size = oldwin->w_width / 2;
924 	if (new_size > available - minwidth - 1)
925 	    new_size = available - minwidth - 1;
926 	if (new_size < wmw1)
927 	    new_size = wmw1;
928 
929 	// if it doesn't fit in the current window, need win_equal()
930 	if (oldwin->w_width - new_size - 1 < p_wmw)
931 	    do_equal = TRUE;
932 
933 	// We don't like to take lines for the new window from a
934 	// 'winfixwidth' window.  Take them from a window to the left or right
935 	// instead, if possible. Add one for the separator.
936 	if (oldwin->w_p_wfw)
937 	    win_setwidth_win(oldwin->w_width + new_size + 1, oldwin);
938 
939 	// Only make all windows the same width if one of them (except oldwin)
940 	// is wider than one of the split windows.
941 	if (!do_equal && p_ea && size == 0 && *p_ead != 'v'
942 					 && oldwin->w_frame->fr_parent != NULL)
943 	{
944 	    frp = oldwin->w_frame->fr_parent->fr_child;
945 	    while (frp != NULL)
946 	    {
947 		if (frp->fr_win != oldwin && frp->fr_win != NULL
948 			&& (frp->fr_win->w_width > new_size
949 			    || frp->fr_win->w_width > oldwin->w_width
950 							      - new_size - 1))
951 		{
952 		    do_equal = TRUE;
953 		    break;
954 		}
955 		frp = frp->fr_next;
956 	    }
957 	}
958     }
959     else
960     {
961 	layout = FR_COL;
962 
963 	/*
964 	 * Check if we are able to split the current window and compute its
965 	 * height.
966 	 */
967 	// Current window requires at least 1 space.
968 	wmh1 = (p_wmh == 0 ? 1 : p_wmh) + WINBAR_HEIGHT(curwin);
969 	needed = wmh1 + STATUS_HEIGHT;
970 	if (flags & WSP_ROOM)
971 	    needed += p_wh - wmh1;
972 	if (flags & (WSP_BOT | WSP_TOP))
973 	{
974 	    minheight = frame_minheight(topframe, NOWIN) + need_status;
975 	    available = topframe->fr_height;
976 	    needed += minheight;
977 	}
978 	else if (p_ea)
979 	{
980 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
981 	    prevfrp = oldwin->w_frame;
982 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
983 							frp = frp->fr_parent)
984 	    {
985 		if (frp->fr_layout == FR_COL)
986 		    FOR_ALL_FRAMES(frp2, frp->fr_child)
987 			if (frp2 != prevfrp)
988 			    minheight += frame_minheight(frp2, NOWIN);
989 		prevfrp = frp;
990 	    }
991 	    available = topframe->fr_height;
992 	    needed += minheight;
993 	}
994 	else
995 	{
996 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
997 	    available = oldwin->w_frame->fr_height;
998 	    needed += minheight;
999 	}
1000 	if (available < needed && new_wp == NULL)
1001 	{
1002 	    emsg(_(e_noroom));
1003 	    return FAIL;
1004 	}
1005 	oldwin_height = oldwin->w_height;
1006 	if (need_status)
1007 	{
1008 	    oldwin->w_status_height = STATUS_HEIGHT;
1009 	    oldwin_height -= STATUS_HEIGHT;
1010 	}
1011 	if (new_size == 0)
1012 	    new_size = oldwin_height / 2;
1013 	if (new_size > available - minheight - STATUS_HEIGHT)
1014 	    new_size = available - minheight - STATUS_HEIGHT;
1015 	if (new_size < wmh1)
1016 	    new_size = wmh1;
1017 
1018 	// if it doesn't fit in the current window, need win_equal()
1019 	if (oldwin_height - new_size - STATUS_HEIGHT < p_wmh)
1020 	    do_equal = TRUE;
1021 
1022 	// We don't like to take lines for the new window from a
1023 	// 'winfixheight' window.  Take them from a window above or below
1024 	// instead, if possible.
1025 	if (oldwin->w_p_wfh)
1026 	{
1027 	    // Set w_fraction now so that the cursor keeps the same relative
1028 	    // vertical position using the old height.
1029 	    set_fraction(oldwin);
1030 	    did_set_fraction = TRUE;
1031 
1032 	    win_setheight_win(oldwin->w_height + new_size + STATUS_HEIGHT,
1033 								      oldwin);
1034 	    oldwin_height = oldwin->w_height;
1035 	    if (need_status)
1036 		oldwin_height -= STATUS_HEIGHT;
1037 	}
1038 
1039 	// Only make all windows the same height if one of them (except oldwin)
1040 	// is higher than one of the split windows.
1041 	if (!do_equal && p_ea && size == 0 && *p_ead != 'h'
1042 	   && oldwin->w_frame->fr_parent != NULL)
1043 	{
1044 	    frp = oldwin->w_frame->fr_parent->fr_child;
1045 	    while (frp != NULL)
1046 	    {
1047 		if (frp->fr_win != oldwin && frp->fr_win != NULL
1048 			&& (frp->fr_win->w_height > new_size
1049 			    || frp->fr_win->w_height > oldwin_height - new_size
1050 							      - STATUS_HEIGHT))
1051 		{
1052 		    do_equal = TRUE;
1053 		    break;
1054 		}
1055 		frp = frp->fr_next;
1056 	    }
1057 	}
1058     }
1059 
1060     /*
1061      * allocate new window structure and link it in the window list
1062      */
1063     if ((flags & WSP_TOP) == 0
1064 	    && ((flags & WSP_BOT)
1065 		|| (flags & WSP_BELOW)
1066 		|| (!(flags & WSP_ABOVE)
1067 		    && ( (flags & WSP_VERT) ? p_spr : p_sb))))
1068     {
1069 	// new window below/right of current one
1070 	if (new_wp == NULL)
1071 	    wp = win_alloc(oldwin, FALSE);
1072 	else
1073 	    win_append(oldwin, wp);
1074     }
1075     else
1076     {
1077 	if (new_wp == NULL)
1078 	    wp = win_alloc(oldwin->w_prev, FALSE);
1079 	else
1080 	    win_append(oldwin->w_prev, wp);
1081     }
1082 
1083     if (new_wp == NULL)
1084     {
1085 	if (wp == NULL)
1086 	    return FAIL;
1087 
1088 	new_frame(wp);
1089 	if (wp->w_frame == NULL)
1090 	{
1091 	    win_free(wp, NULL);
1092 	    return FAIL;
1093 	}
1094 
1095 	// make the contents of the new window the same as the current one
1096 	win_init(wp, curwin, flags);
1097     }
1098 
1099     /*
1100      * Reorganise the tree of frames to insert the new window.
1101      */
1102     if (flags & (WSP_TOP | WSP_BOT))
1103     {
1104 	if ((topframe->fr_layout == FR_COL && (flags & WSP_VERT) == 0)
1105 	    || (topframe->fr_layout == FR_ROW && (flags & WSP_VERT) != 0))
1106 	{
1107 	    curfrp = topframe->fr_child;
1108 	    if (flags & WSP_BOT)
1109 		while (curfrp->fr_next != NULL)
1110 		    curfrp = curfrp->fr_next;
1111 	}
1112 	else
1113 	    curfrp = topframe;
1114 	before = (flags & WSP_TOP);
1115     }
1116     else
1117     {
1118 	curfrp = oldwin->w_frame;
1119 	if (flags & WSP_BELOW)
1120 	    before = FALSE;
1121 	else if (flags & WSP_ABOVE)
1122 	    before = TRUE;
1123 	else if (flags & WSP_VERT)
1124 	    before = !p_spr;
1125 	else
1126 	    before = !p_sb;
1127     }
1128     if (curfrp->fr_parent == NULL || curfrp->fr_parent->fr_layout != layout)
1129     {
1130 	// Need to create a new frame in the tree to make a branch.
1131 	frp = ALLOC_CLEAR_ONE(frame_T);
1132 	*frp = *curfrp;
1133 	curfrp->fr_layout = layout;
1134 	frp->fr_parent = curfrp;
1135 	frp->fr_next = NULL;
1136 	frp->fr_prev = NULL;
1137 	curfrp->fr_child = frp;
1138 	curfrp->fr_win = NULL;
1139 	curfrp = frp;
1140 	if (frp->fr_win != NULL)
1141 	    oldwin->w_frame = frp;
1142 	else
1143 	    FOR_ALL_FRAMES(frp, frp->fr_child)
1144 		frp->fr_parent = curfrp;
1145     }
1146 
1147     if (new_wp == NULL)
1148 	frp = wp->w_frame;
1149     else
1150 	frp = new_wp->w_frame;
1151     frp->fr_parent = curfrp->fr_parent;
1152 
1153     // Insert the new frame at the right place in the frame list.
1154     if (before)
1155 	frame_insert(curfrp, frp);
1156     else
1157 	frame_append(curfrp, frp);
1158 
1159     // Set w_fraction now so that the cursor keeps the same relative
1160     // vertical position.
1161     if (!did_set_fraction)
1162 	set_fraction(oldwin);
1163     wp->w_fraction = oldwin->w_fraction;
1164 
1165     if (flags & WSP_VERT)
1166     {
1167 	wp->w_p_scr = curwin->w_p_scr;
1168 
1169 	if (need_status)
1170 	{
1171 	    win_new_height(oldwin, oldwin->w_height - 1);
1172 	    oldwin->w_status_height = need_status;
1173 	}
1174 	if (flags & (WSP_TOP | WSP_BOT))
1175 	{
1176 	    // set height and row of new window to full height
1177 	    wp->w_winrow = tabline_height();
1178 	    win_new_height(wp, curfrp->fr_height - (p_ls > 0)
1179 							  - WINBAR_HEIGHT(wp));
1180 	    wp->w_status_height = (p_ls > 0);
1181 	}
1182 	else
1183 	{
1184 	    // height and row of new window is same as current window
1185 	    wp->w_winrow = oldwin->w_winrow;
1186 	    win_new_height(wp, VISIBLE_HEIGHT(oldwin));
1187 	    wp->w_status_height = oldwin->w_status_height;
1188 	}
1189 	frp->fr_height = curfrp->fr_height;
1190 
1191 	// "new_size" of the current window goes to the new window, use
1192 	// one column for the vertical separator
1193 	win_new_width(wp, new_size);
1194 	if (before)
1195 	    wp->w_vsep_width = 1;
1196 	else
1197 	{
1198 	    wp->w_vsep_width = oldwin->w_vsep_width;
1199 	    oldwin->w_vsep_width = 1;
1200 	}
1201 	if (flags & (WSP_TOP | WSP_BOT))
1202 	{
1203 	    if (flags & WSP_BOT)
1204 		frame_add_vsep(curfrp);
1205 	    // Set width of neighbor frame
1206 	    frame_new_width(curfrp, curfrp->fr_width
1207 		     - (new_size + ((flags & WSP_TOP) != 0)), flags & WSP_TOP,
1208 								       FALSE);
1209 	}
1210 	else
1211 	    win_new_width(oldwin, oldwin->w_width - (new_size + 1));
1212 	if (before)	// new window left of current one
1213 	{
1214 	    wp->w_wincol = oldwin->w_wincol;
1215 	    oldwin->w_wincol += new_size + 1;
1216 	}
1217 	else		// new window right of current one
1218 	    wp->w_wincol = oldwin->w_wincol + oldwin->w_width + 1;
1219 	frame_fix_width(oldwin);
1220 	frame_fix_width(wp);
1221     }
1222     else
1223     {
1224 	// width and column of new window is same as current window
1225 	if (flags & (WSP_TOP | WSP_BOT))
1226 	{
1227 	    wp->w_wincol = 0;
1228 	    win_new_width(wp, Columns);
1229 	    wp->w_vsep_width = 0;
1230 	}
1231 	else
1232 	{
1233 	    wp->w_wincol = oldwin->w_wincol;
1234 	    win_new_width(wp, oldwin->w_width);
1235 	    wp->w_vsep_width = oldwin->w_vsep_width;
1236 	}
1237 	frp->fr_width = curfrp->fr_width;
1238 
1239 	// "new_size" of the current window goes to the new window, use
1240 	// one row for the status line
1241 	win_new_height(wp, new_size);
1242 	if (flags & (WSP_TOP | WSP_BOT))
1243 	{
1244 	    int new_fr_height = curfrp->fr_height - new_size
1245 							  + WINBAR_HEIGHT(wp) ;
1246 
1247 	    if (!((flags & WSP_BOT) && p_ls == 0))
1248 		new_fr_height -= STATUS_HEIGHT;
1249 	    frame_new_height(curfrp, new_fr_height, flags & WSP_TOP, FALSE);
1250 	}
1251 	else
1252 	    win_new_height(oldwin, oldwin_height - (new_size + STATUS_HEIGHT));
1253 	if (before)	// new window above current one
1254 	{
1255 	    wp->w_winrow = oldwin->w_winrow;
1256 	    wp->w_status_height = STATUS_HEIGHT;
1257 	    oldwin->w_winrow += wp->w_height + STATUS_HEIGHT;
1258 	}
1259 	else		// new window below current one
1260 	{
1261 	    wp->w_winrow = oldwin->w_winrow + VISIBLE_HEIGHT(oldwin)
1262 							       + STATUS_HEIGHT;
1263 	    wp->w_status_height = oldwin->w_status_height;
1264 	    if (!(flags & WSP_BOT))
1265 		oldwin->w_status_height = STATUS_HEIGHT;
1266 	}
1267 	if (flags & WSP_BOT)
1268 	    frame_add_statusline(curfrp);
1269 	frame_fix_height(wp);
1270 	frame_fix_height(oldwin);
1271     }
1272 
1273     if (flags & (WSP_TOP | WSP_BOT))
1274 	(void)win_comp_pos();
1275 
1276     /*
1277      * Both windows need redrawing
1278      */
1279     redraw_win_later(wp, NOT_VALID);
1280     wp->w_redr_status = TRUE;
1281     redraw_win_later(oldwin, NOT_VALID);
1282     oldwin->w_redr_status = TRUE;
1283 
1284     if (need_status)
1285     {
1286 	msg_row = Rows - 1;
1287 	msg_col = sc_col;
1288 	msg_clr_eos_force();	// Old command/ruler may still be there
1289 	comp_col();
1290 	msg_row = Rows - 1;
1291 	msg_col = 0;	// put position back at start of line
1292     }
1293 
1294     /*
1295      * equalize the window sizes.
1296      */
1297     if (do_equal || dir != 0)
1298 	win_equal(wp, TRUE,
1299 		(flags & WSP_VERT) ? (dir == 'v' ? 'b' : 'h')
1300 		: dir == 'h' ? 'b' : 'v');
1301 
1302     // Don't change the window height/width to 'winheight' / 'winwidth' if a
1303     // size was given.
1304     if (flags & WSP_VERT)
1305     {
1306 	i = p_wiw;
1307 	if (size != 0)
1308 	    p_wiw = size;
1309 
1310 # ifdef FEAT_GUI
1311 	// When 'guioptions' includes 'L' or 'R' may have to add scrollbars.
1312 	if (gui.in_use)
1313 	    gui_init_which_components(NULL);
1314 # endif
1315     }
1316     else
1317     {
1318 	i = p_wh;
1319 	if (size != 0)
1320 	    p_wh = size;
1321     }
1322 
1323 #ifdef FEAT_JUMPLIST
1324     // Keep same changelist position in new window.
1325     wp->w_changelistidx = oldwin->w_changelistidx;
1326 #endif
1327 
1328     /*
1329      * make the new window the current window
1330      */
1331     win_enter_ext(wp, FALSE, FALSE, TRUE, TRUE, TRUE);
1332     if (flags & WSP_VERT)
1333 	p_wiw = i;
1334     else
1335 	p_wh = i;
1336 
1337     return OK;
1338 }
1339 
1340 
1341 /*
1342  * Initialize window "newp" from window "oldp".
1343  * Used when splitting a window and when creating a new tab page.
1344  * The windows will both edit the same buffer.
1345  * WSP_NEWLOC may be specified in flags to prevent the location list from
1346  * being copied.
1347  */
1348     static void
1349 win_init(win_T *newp, win_T *oldp, int flags UNUSED)
1350 {
1351     int		i;
1352 
1353     newp->w_buffer = oldp->w_buffer;
1354 #ifdef FEAT_SYN_HL
1355     newp->w_s = &(oldp->w_buffer->b_s);
1356 #endif
1357     oldp->w_buffer->b_nwindows++;
1358     newp->w_cursor = oldp->w_cursor;
1359     newp->w_valid = 0;
1360     newp->w_curswant = oldp->w_curswant;
1361     newp->w_set_curswant = oldp->w_set_curswant;
1362     newp->w_topline = oldp->w_topline;
1363 #ifdef FEAT_DIFF
1364     newp->w_topfill = oldp->w_topfill;
1365 #endif
1366     newp->w_leftcol = oldp->w_leftcol;
1367     newp->w_pcmark = oldp->w_pcmark;
1368     newp->w_prev_pcmark = oldp->w_prev_pcmark;
1369     newp->w_alt_fnum = oldp->w_alt_fnum;
1370     newp->w_wrow = oldp->w_wrow;
1371     newp->w_fraction = oldp->w_fraction;
1372     newp->w_prev_fraction_row = oldp->w_prev_fraction_row;
1373 #ifdef FEAT_JUMPLIST
1374     copy_jumplist(oldp, newp);
1375 #endif
1376 #ifdef FEAT_QUICKFIX
1377     if (flags & WSP_NEWLOC)
1378     {
1379 	// Don't copy the location list.
1380 	newp->w_llist = NULL;
1381 	newp->w_llist_ref = NULL;
1382     }
1383     else
1384 	copy_loclist_stack(oldp, newp);
1385 #endif
1386     newp->w_localdir = (oldp->w_localdir == NULL)
1387 				    ? NULL : vim_strsave(oldp->w_localdir);
1388     newp->w_prevdir = (oldp->w_prevdir == NULL)
1389 				    ? NULL : vim_strsave(oldp->w_prevdir);
1390 
1391     // copy tagstack and folds
1392     for (i = 0; i < oldp->w_tagstacklen; i++)
1393     {
1394 	taggy_T	*tag = &newp->w_tagstack[i];
1395 	*tag = oldp->w_tagstack[i];
1396 	if (tag->tagname != NULL)
1397 	    tag->tagname = vim_strsave(tag->tagname);
1398 	if (tag->user_data != NULL)
1399 	    tag->user_data = vim_strsave(tag->user_data);
1400     }
1401     newp->w_tagstackidx = oldp->w_tagstackidx;
1402     newp->w_tagstacklen = oldp->w_tagstacklen;
1403 #ifdef FEAT_FOLDING
1404     copyFoldingState(oldp, newp);
1405 #endif
1406 
1407     win_init_some(newp, oldp);
1408 
1409 #ifdef FEAT_SYN_HL
1410     check_colorcolumn(newp);
1411 #endif
1412 }
1413 
1414 /*
1415  * Initialize window "newp" from window "old".
1416  * Only the essential things are copied.
1417  */
1418     static void
1419 win_init_some(win_T *newp, win_T *oldp)
1420 {
1421     // Use the same argument list.
1422     newp->w_alist = oldp->w_alist;
1423     ++newp->w_alist->al_refcount;
1424     newp->w_arg_idx = oldp->w_arg_idx;
1425 
1426     // copy options from existing window
1427     win_copy_options(oldp, newp);
1428 }
1429 
1430 /*
1431  * Return TRUE if "win" is a global popup or a popup in the current tab page.
1432  */
1433     int
1434 win_valid_popup(win_T *win UNUSED)
1435 {
1436 #ifdef FEAT_PROP_POPUP
1437     win_T	*wp;
1438 
1439     FOR_ALL_POPUPWINS(wp)
1440 	if (wp == win)
1441 	    return TRUE;
1442     FOR_ALL_POPUPWINS_IN_TAB(curtab, wp)
1443 	if (wp == win)
1444 	    return TRUE;
1445 #endif
1446     return FALSE;
1447 }
1448 
1449 /*
1450  * Check if "win" is a pointer to an existing window in the current tab page.
1451  */
1452     int
1453 win_valid(win_T *win)
1454 {
1455     win_T	*wp;
1456 
1457     if (win == NULL)
1458 	return FALSE;
1459     FOR_ALL_WINDOWS(wp)
1460 	if (wp == win)
1461 	    return TRUE;
1462     return win_valid_popup(win);
1463 }
1464 
1465 /*
1466  * Check if "win" is a pointer to an existing window in any tab page.
1467  */
1468     int
1469 win_valid_any_tab(win_T *win)
1470 {
1471     win_T	*wp;
1472     tabpage_T	*tp;
1473 
1474     if (win == NULL)
1475 	return FALSE;
1476     FOR_ALL_TABPAGES(tp)
1477     {
1478 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
1479 	{
1480 	    if (wp == win)
1481 		return TRUE;
1482 	}
1483 #ifdef FEAT_PROP_POPUP
1484 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
1485 	    if (wp == win)
1486 		return TRUE;
1487 #endif
1488     }
1489     return win_valid_popup(win);
1490 }
1491 
1492 /*
1493  * Return the number of windows.
1494  */
1495     int
1496 win_count(void)
1497 {
1498     win_T	*wp;
1499     int		count = 0;
1500 
1501     FOR_ALL_WINDOWS(wp)
1502 	++count;
1503     return count;
1504 }
1505 
1506 /*
1507  * Make "count" windows on the screen.
1508  * Return actual number of windows on the screen.
1509  * Must be called when there is just one window, filling the whole screen
1510  * (excluding the command line).
1511  */
1512     int
1513 make_windows(
1514     int		count,
1515     int		vertical UNUSED)  // split windows vertically if TRUE
1516 {
1517     int		maxcount;
1518     int		todo;
1519 
1520     if (vertical)
1521     {
1522 	// Each windows needs at least 'winminwidth' lines and a separator
1523 	// column.
1524 	maxcount = (curwin->w_width + curwin->w_vsep_width
1525 					     - (p_wiw - p_wmw)) / (p_wmw + 1);
1526     }
1527     else
1528     {
1529 	// Each window needs at least 'winminheight' lines and a status line.
1530 	maxcount = (VISIBLE_HEIGHT(curwin) + curwin->w_status_height
1531 				  - (p_wh - p_wmh)) / (p_wmh + STATUS_HEIGHT);
1532     }
1533 
1534     if (maxcount < 2)
1535 	maxcount = 2;
1536     if (count > maxcount)
1537 	count = maxcount;
1538 
1539     /*
1540      * add status line now, otherwise first window will be too big
1541      */
1542     if (count > 1)
1543 	last_status(TRUE);
1544 
1545     /*
1546      * Don't execute autocommands while creating the windows.  Must do that
1547      * when putting the buffers in the windows.
1548      */
1549     block_autocmds();
1550 
1551     // todo is number of windows left to create
1552     for (todo = count - 1; todo > 0; --todo)
1553 	if (vertical)
1554 	{
1555 	    if (win_split(curwin->w_width - (curwin->w_width - todo)
1556 			/ (todo + 1) - 1, WSP_VERT | WSP_ABOVE) == FAIL)
1557 		break;
1558 	}
1559 	else
1560 	{
1561 	    if (win_split(curwin->w_height - (curwin->w_height - todo
1562 			    * STATUS_HEIGHT) / (todo + 1)
1563 			- STATUS_HEIGHT, WSP_ABOVE) == FAIL)
1564 		break;
1565 	}
1566 
1567     unblock_autocmds();
1568 
1569     // return actual number of windows
1570     return (count - todo);
1571 }
1572 
1573 /*
1574  * Exchange current and next window
1575  */
1576     static void
1577 win_exchange(long Prenum)
1578 {
1579     frame_T	*frp;
1580     frame_T	*frp2;
1581     win_T	*wp;
1582     win_T	*wp2;
1583     int		temp;
1584 
1585     if (ERROR_IF_ANY_POPUP_WINDOW)
1586 	return;
1587     if (ONE_WINDOW)	    // just one window
1588     {
1589 	beep_flush();
1590 	return;
1591     }
1592 
1593 #ifdef FEAT_GUI
1594     need_mouse_correct = TRUE;
1595 #endif
1596 
1597     /*
1598      * find window to exchange with
1599      */
1600     if (Prenum)
1601     {
1602 	frp = curwin->w_frame->fr_parent->fr_child;
1603 	while (frp != NULL && --Prenum > 0)
1604 	    frp = frp->fr_next;
1605     }
1606     else if (curwin->w_frame->fr_next != NULL)	// Swap with next
1607 	frp = curwin->w_frame->fr_next;
1608     else    // Swap last window in row/col with previous
1609 	frp = curwin->w_frame->fr_prev;
1610 
1611     // We can only exchange a window with another window, not with a frame
1612     // containing windows.
1613     if (frp == NULL || frp->fr_win == NULL || frp->fr_win == curwin)
1614 	return;
1615     wp = frp->fr_win;
1616 
1617 /*
1618  * 1. remove curwin from the list. Remember after which window it was in wp2
1619  * 2. insert curwin before wp in the list
1620  * if wp != wp2
1621  *    3. remove wp from the list
1622  *    4. insert wp after wp2
1623  * 5. exchange the status line height and vsep width.
1624  */
1625     wp2 = curwin->w_prev;
1626     frp2 = curwin->w_frame->fr_prev;
1627     if (wp->w_prev != curwin)
1628     {
1629 	win_remove(curwin, NULL);
1630 	frame_remove(curwin->w_frame);
1631 	win_append(wp->w_prev, curwin);
1632 	frame_insert(frp, curwin->w_frame);
1633     }
1634     if (wp != wp2)
1635     {
1636 	win_remove(wp, NULL);
1637 	frame_remove(wp->w_frame);
1638 	win_append(wp2, wp);
1639 	if (frp2 == NULL)
1640 	    frame_insert(wp->w_frame->fr_parent->fr_child, wp->w_frame);
1641 	else
1642 	    frame_append(frp2, wp->w_frame);
1643     }
1644     temp = curwin->w_status_height;
1645     curwin->w_status_height = wp->w_status_height;
1646     wp->w_status_height = temp;
1647     temp = curwin->w_vsep_width;
1648     curwin->w_vsep_width = wp->w_vsep_width;
1649     wp->w_vsep_width = temp;
1650 
1651     // If the windows are not in the same frame, exchange the sizes to avoid
1652     // messing up the window layout.  Otherwise fix the frame sizes.
1653     if (curwin->w_frame->fr_parent != wp->w_frame->fr_parent)
1654     {
1655 	temp = curwin->w_height;
1656 	curwin->w_height = wp->w_height;
1657 	wp->w_height = temp;
1658 	temp = curwin->w_width;
1659 	curwin->w_width = wp->w_width;
1660 	wp->w_width = temp;
1661     }
1662     else
1663     {
1664 	frame_fix_height(curwin);
1665 	frame_fix_height(wp);
1666 	frame_fix_width(curwin);
1667 	frame_fix_width(wp);
1668     }
1669 
1670     (void)win_comp_pos();		// recompute window positions
1671 
1672     win_enter(wp, TRUE);
1673     redraw_all_later(NOT_VALID);
1674 }
1675 
1676 /*
1677  * rotate windows: if upwards TRUE the second window becomes the first one
1678  *		   if upwards FALSE the first window becomes the second one
1679  */
1680     static void
1681 win_rotate(int upwards, int count)
1682 {
1683     win_T	*wp1;
1684     win_T	*wp2;
1685     frame_T	*frp;
1686     int		n;
1687 
1688     if (ONE_WINDOW)		// nothing to do
1689     {
1690 	beep_flush();
1691 	return;
1692     }
1693 
1694 #ifdef FEAT_GUI
1695     need_mouse_correct = TRUE;
1696 #endif
1697 
1698     // Check if all frames in this row/col have one window.
1699     FOR_ALL_FRAMES(frp, curwin->w_frame->fr_parent->fr_child)
1700 	if (frp->fr_win == NULL)
1701 	{
1702 	    emsg(_("E443: Cannot rotate when another window is split"));
1703 	    return;
1704 	}
1705 
1706     while (count--)
1707     {
1708 	if (upwards)		// first window becomes last window
1709 	{
1710 	    // remove first window/frame from the list
1711 	    frp = curwin->w_frame->fr_parent->fr_child;
1712 	    wp1 = frp->fr_win;
1713 	    win_remove(wp1, NULL);
1714 	    frame_remove(frp);
1715 
1716 	    // find last frame and append removed window/frame after it
1717 	    for ( ; frp->fr_next != NULL; frp = frp->fr_next)
1718 		;
1719 	    win_append(frp->fr_win, wp1);
1720 	    frame_append(frp, wp1->w_frame);
1721 
1722 	    wp2 = frp->fr_win;		// previously last window
1723 	}
1724 	else			// last window becomes first window
1725 	{
1726 	    // find last window/frame in the list and remove it
1727 	    for (frp = curwin->w_frame; frp->fr_next != NULL;
1728 							   frp = frp->fr_next)
1729 		;
1730 	    wp1 = frp->fr_win;
1731 	    wp2 = wp1->w_prev;		    // will become last window
1732 	    win_remove(wp1, NULL);
1733 	    frame_remove(frp);
1734 
1735 	    // append the removed window/frame before the first in the list
1736 	    win_append(frp->fr_parent->fr_child->fr_win->w_prev, wp1);
1737 	    frame_insert(frp->fr_parent->fr_child, frp);
1738 	}
1739 
1740 	// exchange status height and vsep width of old and new last window
1741 	n = wp2->w_status_height;
1742 	wp2->w_status_height = wp1->w_status_height;
1743 	wp1->w_status_height = n;
1744 	frame_fix_height(wp1);
1745 	frame_fix_height(wp2);
1746 	n = wp2->w_vsep_width;
1747 	wp2->w_vsep_width = wp1->w_vsep_width;
1748 	wp1->w_vsep_width = n;
1749 	frame_fix_width(wp1);
1750 	frame_fix_width(wp2);
1751 
1752 	// recompute w_winrow and w_wincol for all windows
1753 	(void)win_comp_pos();
1754     }
1755 
1756     redraw_all_later(NOT_VALID);
1757 }
1758 
1759 /*
1760  * Move the current window to the very top/bottom/left/right of the screen.
1761  */
1762     static void
1763 win_totop(int size, int flags)
1764 {
1765     int		dir;
1766     int		height = curwin->w_height;
1767 
1768     if (ONE_WINDOW)
1769     {
1770 	beep_flush();
1771 	return;
1772     }
1773     if (check_split_disallowed() == FAIL)
1774 	return;
1775 
1776     // Remove the window and frame from the tree of frames.
1777     (void)winframe_remove(curwin, &dir, NULL);
1778     win_remove(curwin, NULL);
1779     last_status(FALSE);	    // may need to remove last status line
1780     (void)win_comp_pos();   // recompute window positions
1781 
1782     // Split a window on the desired side and put the window there.
1783     (void)win_split_ins(size, flags, curwin, dir);
1784     if (!(flags & WSP_VERT))
1785     {
1786 	win_setheight(height);
1787 	if (p_ea)
1788 	    win_equal(curwin, TRUE, 'v');
1789     }
1790 
1791 #if defined(FEAT_GUI)
1792     // When 'guioptions' includes 'L' or 'R' may have to remove or add
1793     // scrollbars.  Have to update them anyway.
1794     gui_may_update_scrollbars();
1795 #endif
1796 }
1797 
1798 /*
1799  * Move window "win1" to below/right of "win2" and make "win1" the current
1800  * window.  Only works within the same frame!
1801  */
1802     void
1803 win_move_after(win_T *win1, win_T *win2)
1804 {
1805     int		height;
1806 
1807     // check if the arguments are reasonable
1808     if (win1 == win2)
1809 	return;
1810 
1811     // check if there is something to do
1812     if (win2->w_next != win1)
1813     {
1814 	if (win1->w_frame->fr_parent != win2->w_frame->fr_parent)
1815 	{
1816 	    iemsg("INTERNAL: trying to move a window into another frame");
1817 	    return;
1818 	}
1819 
1820 	// may need to move the status line/vertical separator of the last
1821 	// window
1822 	if (win1 == lastwin)
1823 	{
1824 	    height = win1->w_prev->w_status_height;
1825 	    win1->w_prev->w_status_height = win1->w_status_height;
1826 	    win1->w_status_height = height;
1827 	    if (win1->w_prev->w_vsep_width == 1)
1828 	    {
1829 		// Remove the vertical separator from the last-but-one window,
1830 		// add it to the last window.  Adjust the frame widths.
1831 		win1->w_prev->w_vsep_width = 0;
1832 		win1->w_prev->w_frame->fr_width -= 1;
1833 		win1->w_vsep_width = 1;
1834 		win1->w_frame->fr_width += 1;
1835 	    }
1836 	}
1837 	else if (win2 == lastwin)
1838 	{
1839 	    height = win1->w_status_height;
1840 	    win1->w_status_height = win2->w_status_height;
1841 	    win2->w_status_height = height;
1842 	    if (win1->w_vsep_width == 1)
1843 	    {
1844 		// Remove the vertical separator from win1, add it to the last
1845 		// window, win2.  Adjust the frame widths.
1846 		win2->w_vsep_width = 1;
1847 		win2->w_frame->fr_width += 1;
1848 		win1->w_vsep_width = 0;
1849 		win1->w_frame->fr_width -= 1;
1850 	    }
1851 	}
1852 	win_remove(win1, NULL);
1853 	frame_remove(win1->w_frame);
1854 	win_append(win2, win1);
1855 	frame_append(win2->w_frame, win1->w_frame);
1856 
1857 	(void)win_comp_pos();	// recompute w_winrow for all windows
1858 	redraw_later(NOT_VALID);
1859     }
1860     win_enter(win1, FALSE);
1861 }
1862 
1863 /*
1864  * Make all windows the same height.
1865  * 'next_curwin' will soon be the current window, make sure it has enough
1866  * rows.
1867  */
1868     void
1869 win_equal(
1870     win_T	*next_curwin,	// pointer to current window to be or NULL
1871     int		current,	// do only frame with current window
1872     int		dir)		// 'v' for vertically, 'h' for horizontally,
1873 				// 'b' for both, 0 for using p_ead
1874 {
1875     if (dir == 0)
1876 	dir = *p_ead;
1877     win_equal_rec(next_curwin == NULL ? curwin : next_curwin, current,
1878 		      topframe, dir, 0, tabline_height(),
1879 					   (int)Columns, topframe->fr_height);
1880 }
1881 
1882 /*
1883  * Set a frame to a new position and height, spreading the available room
1884  * equally over contained frames.
1885  * The window "next_curwin" (if not NULL) should at least get the size from
1886  * 'winheight' and 'winwidth' if possible.
1887  */
1888     static void
1889 win_equal_rec(
1890     win_T	*next_curwin,	// pointer to current window to be or NULL
1891     int		current,	// do only frame with current window
1892     frame_T	*topfr,		// frame to set size off
1893     int		dir,		// 'v', 'h' or 'b', see win_equal()
1894     int		col,		// horizontal position for frame
1895     int		row,		// vertical position for frame
1896     int		width,		// new width of frame
1897     int		height)		// new height of frame
1898 {
1899     int		n, m;
1900     int		extra_sep = 0;
1901     int		wincount, totwincount = 0;
1902     frame_T	*fr;
1903     int		next_curwin_size = 0;
1904     int		room = 0;
1905     int		new_size;
1906     int		has_next_curwin = 0;
1907     int		hnc;
1908 
1909     if (topfr->fr_layout == FR_LEAF)
1910     {
1911 	// Set the width/height of this frame.
1912 	// Redraw when size or position changes
1913 	if (topfr->fr_height != height || topfr->fr_win->w_winrow != row
1914 		|| topfr->fr_width != width || topfr->fr_win->w_wincol != col
1915 	   )
1916 	{
1917 	    topfr->fr_win->w_winrow = row;
1918 	    frame_new_height(topfr, height, FALSE, FALSE);
1919 	    topfr->fr_win->w_wincol = col;
1920 	    frame_new_width(topfr, width, FALSE, FALSE);
1921 	    redraw_all_later(NOT_VALID);
1922 	}
1923     }
1924     else if (topfr->fr_layout == FR_ROW)
1925     {
1926 	topfr->fr_width = width;
1927 	topfr->fr_height = height;
1928 
1929 	if (dir != 'v')			// equalize frame widths
1930 	{
1931 	    // Compute the maximum number of windows horizontally in this
1932 	    // frame.
1933 	    n = frame_minwidth(topfr, NOWIN);
1934 	    // add one for the rightmost window, it doesn't have a separator
1935 	    if (col + width == Columns)
1936 		extra_sep = 1;
1937 	    else
1938 		extra_sep = 0;
1939 	    totwincount = (n + extra_sep) / (p_wmw + 1);
1940 	    has_next_curwin = frame_has_win(topfr, next_curwin);
1941 
1942 	    /*
1943 	     * Compute width for "next_curwin" window and room available for
1944 	     * other windows.
1945 	     * "m" is the minimal width when counting p_wiw for "next_curwin".
1946 	     */
1947 	    m = frame_minwidth(topfr, next_curwin);
1948 	    room = width - m;
1949 	    if (room < 0)
1950 	    {
1951 		next_curwin_size = p_wiw + room;
1952 		room = 0;
1953 	    }
1954 	    else
1955 	    {
1956 		next_curwin_size = -1;
1957 		FOR_ALL_FRAMES(fr, topfr->fr_child)
1958 		{
1959 		    // If 'winfixwidth' set keep the window width if
1960 		    // possible.
1961 		    // Watch out for this window being the next_curwin.
1962 		    if (frame_fixed_width(fr))
1963 		    {
1964 			n = frame_minwidth(fr, NOWIN);
1965 			new_size = fr->fr_width;
1966 			if (frame_has_win(fr, next_curwin))
1967 			{
1968 			    room += p_wiw - p_wmw;
1969 			    next_curwin_size = 0;
1970 			    if (new_size < p_wiw)
1971 				new_size = p_wiw;
1972 			}
1973 			else
1974 			    // These windows don't use up room.
1975 			    totwincount -= (n + (fr->fr_next == NULL
1976 					      ? extra_sep : 0)) / (p_wmw + 1);
1977 			room -= new_size - n;
1978 			if (room < 0)
1979 			{
1980 			    new_size += room;
1981 			    room = 0;
1982 			}
1983 			fr->fr_newwidth = new_size;
1984 		    }
1985 		}
1986 		if (next_curwin_size == -1)
1987 		{
1988 		    if (!has_next_curwin)
1989 			next_curwin_size = 0;
1990 		    else if (totwincount > 1
1991 			    && (room + (totwincount - 2))
1992 						  / (totwincount - 1) > p_wiw)
1993 		    {
1994 			// Can make all windows wider than 'winwidth', spread
1995 			// the room equally.
1996 			next_curwin_size = (room + p_wiw
1997 					    + (totwincount - 1) * p_wmw
1998 					    + (totwincount - 1)) / totwincount;
1999 			room -= next_curwin_size - p_wiw;
2000 		    }
2001 		    else
2002 			next_curwin_size = p_wiw;
2003 		}
2004 	    }
2005 
2006 	    if (has_next_curwin)
2007 		--totwincount;		// don't count curwin
2008 	}
2009 
2010 	FOR_ALL_FRAMES(fr, topfr->fr_child)
2011 	{
2012 	    wincount = 1;
2013 	    if (fr->fr_next == NULL)
2014 		// last frame gets all that remains (avoid roundoff error)
2015 		new_size = width;
2016 	    else if (dir == 'v')
2017 		new_size = fr->fr_width;
2018 	    else if (frame_fixed_width(fr))
2019 	    {
2020 		new_size = fr->fr_newwidth;
2021 		wincount = 0;	    // doesn't count as a sizeable window
2022 	    }
2023 	    else
2024 	    {
2025 		// Compute the maximum number of windows horiz. in "fr".
2026 		n = frame_minwidth(fr, NOWIN);
2027 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2028 								/ (p_wmw + 1);
2029 		m = frame_minwidth(fr, next_curwin);
2030 		if (has_next_curwin)
2031 		    hnc = frame_has_win(fr, next_curwin);
2032 		else
2033 		    hnc = FALSE;
2034 		if (hnc)	    // don't count next_curwin
2035 		    --wincount;
2036 		if (totwincount == 0)
2037 		    new_size = room;
2038 		else
2039 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2040 								/ totwincount;
2041 		if (hnc)	    // add next_curwin size
2042 		{
2043 		    next_curwin_size -= p_wiw - (m - n);
2044 		    new_size += next_curwin_size;
2045 		    room -= new_size - next_curwin_size;
2046 		}
2047 		else
2048 		    room -= new_size;
2049 		new_size += n;
2050 	    }
2051 
2052 	    // Skip frame that is full width when splitting or closing a
2053 	    // window, unless equalizing all frames.
2054 	    if (!current || dir != 'v' || topfr->fr_parent != NULL
2055 		    || (new_size != fr->fr_width)
2056 		    || frame_has_win(fr, next_curwin))
2057 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2058 							    new_size, height);
2059 	    col += new_size;
2060 	    width -= new_size;
2061 	    totwincount -= wincount;
2062 	}
2063     }
2064     else // topfr->fr_layout == FR_COL
2065     {
2066 	topfr->fr_width = width;
2067 	topfr->fr_height = height;
2068 
2069 	if (dir != 'h')			// equalize frame heights
2070 	{
2071 	    // Compute maximum number of windows vertically in this frame.
2072 	    n = frame_minheight(topfr, NOWIN);
2073 	    // add one for the bottom window if it doesn't have a statusline
2074 	    if (row + height == cmdline_row && p_ls == 0)
2075 		extra_sep = 1;
2076 	    else
2077 		extra_sep = 0;
2078 	    totwincount = (n + extra_sep) / (p_wmh + 1);
2079 	    has_next_curwin = frame_has_win(topfr, next_curwin);
2080 
2081 	    /*
2082 	     * Compute height for "next_curwin" window and room available for
2083 	     * other windows.
2084 	     * "m" is the minimal height when counting p_wh for "next_curwin".
2085 	     */
2086 	    m = frame_minheight(topfr, next_curwin);
2087 	    room = height - m;
2088 	    if (room < 0)
2089 	    {
2090 		// The room is less then 'winheight', use all space for the
2091 		// current window.
2092 		next_curwin_size = p_wh + room;
2093 		room = 0;
2094 	    }
2095 	    else
2096 	    {
2097 		next_curwin_size = -1;
2098 		FOR_ALL_FRAMES(fr, topfr->fr_child)
2099 		{
2100 		    // If 'winfixheight' set keep the window height if
2101 		    // possible.
2102 		    // Watch out for this window being the next_curwin.
2103 		    if (frame_fixed_height(fr))
2104 		    {
2105 			n = frame_minheight(fr, NOWIN);
2106 			new_size = fr->fr_height;
2107 			if (frame_has_win(fr, next_curwin))
2108 			{
2109 			    room += p_wh - p_wmh;
2110 			    next_curwin_size = 0;
2111 			    if (new_size < p_wh)
2112 				new_size = p_wh;
2113 			}
2114 			else
2115 			    // These windows don't use up room.
2116 			    totwincount -= (n + (fr->fr_next == NULL
2117 					      ? extra_sep : 0)) / (p_wmh + 1);
2118 			room -= new_size - n;
2119 			if (room < 0)
2120 			{
2121 			    new_size += room;
2122 			    room = 0;
2123 			}
2124 			fr->fr_newheight = new_size;
2125 		    }
2126 		}
2127 		if (next_curwin_size == -1)
2128 		{
2129 		    if (!has_next_curwin)
2130 			next_curwin_size = 0;
2131 		    else if (totwincount > 1
2132 			    && (room + (totwincount - 2))
2133 						   / (totwincount - 1) > p_wh)
2134 		    {
2135 			// can make all windows higher than 'winheight',
2136 			// spread the room equally.
2137 			next_curwin_size = (room + p_wh
2138 					   + (totwincount - 1) * p_wmh
2139 					   + (totwincount - 1)) / totwincount;
2140 			room -= next_curwin_size - p_wh;
2141 		    }
2142 		    else
2143 			next_curwin_size = p_wh;
2144 		}
2145 	    }
2146 
2147 	    if (has_next_curwin)
2148 		--totwincount;		// don't count curwin
2149 	}
2150 
2151 	FOR_ALL_FRAMES(fr, topfr->fr_child)
2152 	{
2153 	    wincount = 1;
2154 	    if (fr->fr_next == NULL)
2155 		// last frame gets all that remains (avoid roundoff error)
2156 		new_size = height;
2157 	    else if (dir == 'h')
2158 		new_size = fr->fr_height;
2159 	    else if (frame_fixed_height(fr))
2160 	    {
2161 		new_size = fr->fr_newheight;
2162 		wincount = 0;	    // doesn't count as a sizeable window
2163 	    }
2164 	    else
2165 	    {
2166 		// Compute the maximum number of windows vert. in "fr".
2167 		n = frame_minheight(fr, NOWIN);
2168 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2169 								/ (p_wmh + 1);
2170 		m = frame_minheight(fr, next_curwin);
2171 		if (has_next_curwin)
2172 		    hnc = frame_has_win(fr, next_curwin);
2173 		else
2174 		    hnc = FALSE;
2175 		if (hnc)	    // don't count next_curwin
2176 		    --wincount;
2177 		if (totwincount == 0)
2178 		    new_size = room;
2179 		else
2180 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2181 								/ totwincount;
2182 		if (hnc)	    // add next_curwin size
2183 		{
2184 		    next_curwin_size -= p_wh - (m - n);
2185 		    new_size += next_curwin_size;
2186 		    room -= new_size - next_curwin_size;
2187 		}
2188 		else
2189 		    room -= new_size;
2190 		new_size += n;
2191 	    }
2192 	    // Skip frame that is full width when splitting or closing a
2193 	    // window, unless equalizing all frames.
2194 	    if (!current || dir != 'h' || topfr->fr_parent != NULL
2195 		    || (new_size != fr->fr_height)
2196 		    || frame_has_win(fr, next_curwin))
2197 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2198 							     width, new_size);
2199 	    row += new_size;
2200 	    height -= new_size;
2201 	    totwincount -= wincount;
2202 	}
2203     }
2204 }
2205 
2206 #ifdef FEAT_JOB_CHANNEL
2207     static void
2208 leaving_window(win_T *win)
2209 {
2210     // Only matters for a prompt window.
2211     if (!bt_prompt(win->w_buffer))
2212 	return;
2213 
2214     // When leaving a prompt window stop Insert mode and perhaps restart
2215     // it when entering that window again.
2216     win->w_buffer->b_prompt_insert = restart_edit;
2217     if (restart_edit != 0 && mode_displayed)
2218 	clear_cmdline = TRUE;		// unshow mode later
2219     restart_edit = NUL;
2220 
2221     // When leaving the window (or closing the window) was done from a
2222     // callback we need to break out of the Insert mode loop and restart Insert
2223     // mode when entering the window again.
2224     if (State & INSERT)
2225     {
2226 	stop_insert_mode = TRUE;
2227 	if (win->w_buffer->b_prompt_insert == NUL)
2228 	    win->w_buffer->b_prompt_insert = 'A';
2229     }
2230 }
2231 
2232     static void
2233 entering_window(win_T *win)
2234 {
2235     // Only matters for a prompt window.
2236     if (!bt_prompt(win->w_buffer))
2237 	return;
2238 
2239     // When switching to a prompt buffer that was in Insert mode, don't stop
2240     // Insert mode, it may have been set in leaving_window().
2241     if (win->w_buffer->b_prompt_insert != NUL)
2242 	stop_insert_mode = FALSE;
2243 
2244     // When entering the prompt window restart Insert mode if we were in Insert
2245     // mode when we left it.
2246     restart_edit = win->w_buffer->b_prompt_insert;
2247 }
2248 #endif
2249 
2250 /*
2251  * Close all windows for buffer "buf".
2252  */
2253     void
2254 close_windows(
2255     buf_T	*buf,
2256     int		keep_curwin)	    // don't close "curwin"
2257 {
2258     win_T	*wp;
2259     tabpage_T   *tp, *nexttp;
2260     int		h = tabline_height();
2261     int		count = tabpage_index(NULL);
2262 
2263     ++RedrawingDisabled;
2264 
2265     for (wp = firstwin; wp != NULL && !ONE_WINDOW; )
2266     {
2267 	if (wp->w_buffer == buf && (!keep_curwin || wp != curwin)
2268 		&& !(wp->w_closing || wp->w_buffer->b_locked > 0))
2269 	{
2270 	    if (win_close(wp, FALSE) == FAIL)
2271 		// If closing the window fails give up, to avoid looping
2272 		// forever.
2273 		break;
2274 
2275 	    // Start all over, autocommands may change the window layout.
2276 	    wp = firstwin;
2277 	}
2278 	else
2279 	    wp = wp->w_next;
2280     }
2281 
2282     // Also check windows in other tab pages.
2283     for (tp = first_tabpage; tp != NULL; tp = nexttp)
2284     {
2285 	nexttp = tp->tp_next;
2286 	if (tp != curtab)
2287 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
2288 		if (wp->w_buffer == buf
2289 		    && !(wp->w_closing || wp->w_buffer->b_locked > 0))
2290 		{
2291 		    win_close_othertab(wp, FALSE, tp);
2292 
2293 		    // Start all over, the tab page may be closed and
2294 		    // autocommands may change the window layout.
2295 		    nexttp = first_tabpage;
2296 		    break;
2297 		}
2298     }
2299 
2300     --RedrawingDisabled;
2301 
2302     if (count != tabpage_index(NULL))
2303 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2304 
2305     redraw_tabline = TRUE;
2306     if (h != tabline_height())
2307 	shell_new_rows();
2308 }
2309 
2310 /*
2311  * Return TRUE if the current window is the only window that exists (ignoring
2312  * "aucmd_win").
2313  * Returns FALSE if there is a window, possibly in another tab page.
2314  */
2315     static int
2316 last_window(void)
2317 {
2318     return (one_window() && first_tabpage->tp_next == NULL);
2319 }
2320 
2321 /*
2322  * Return TRUE if there is only one window other than "aucmd_win" in the
2323  * current tab page.
2324  */
2325     int
2326 one_window(void)
2327 {
2328     win_T	*wp;
2329     int		seen_one = FALSE;
2330 
2331     FOR_ALL_WINDOWS(wp)
2332     {
2333 	if (wp != aucmd_win)
2334 	{
2335 	    if (seen_one)
2336 		return FALSE;
2337 	    seen_one = TRUE;
2338 	}
2339     }
2340     return TRUE;
2341 }
2342 
2343 /*
2344  * Close the possibly last window in a tab page.
2345  * Returns TRUE when the window was closed already.
2346  */
2347     static int
2348 close_last_window_tabpage(
2349     win_T	*win,
2350     int		free_buf,
2351     tabpage_T   *prev_curtab)
2352 {
2353     if (ONE_WINDOW)
2354     {
2355 	buf_T	*old_curbuf = curbuf;
2356 
2357 	/*
2358 	 * Closing the last window in a tab page.  First go to another tab
2359 	 * page and then close the window and the tab page.  This avoids that
2360 	 * curwin and curtab are invalid while we are freeing memory, they may
2361 	 * be used in GUI events.
2362 	 * Don't trigger autocommands yet, they may use wrong values, so do
2363 	 * that below.
2364 	 */
2365 	goto_tabpage_tp(alt_tabpage(), FALSE, TRUE);
2366 	redraw_tabline = TRUE;
2367 
2368 	// Safety check: Autocommands may have closed the window when jumping
2369 	// to the other tab page.
2370 	if (valid_tabpage(prev_curtab) && prev_curtab->tp_firstwin == win)
2371 	{
2372 	    int	    h = tabline_height();
2373 
2374 	    win_close_othertab(win, free_buf, prev_curtab);
2375 	    if (h != tabline_height())
2376 		shell_new_rows();
2377 	}
2378 #ifdef FEAT_JOB_CHANNEL
2379 	entering_window(curwin);
2380 #endif
2381 	// Since goto_tabpage_tp above did not trigger *Enter autocommands, do
2382 	// that now.
2383 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2384 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
2385 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
2386 	if (old_curbuf != curbuf)
2387 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2388 	return TRUE;
2389     }
2390     return FALSE;
2391 }
2392 
2393 /*
2394  * Close the buffer of "win" and unload it if "action" is DOBUF_UNLOAD.
2395  * "action" can also be zero (do nothing) or DOBUF_WIPE.
2396  * "abort_if_last" is passed to close_buffer(): abort closing if all other
2397  * windows are closed.
2398  */
2399     static void
2400 win_close_buffer(win_T *win, int action, int abort_if_last)
2401 {
2402 #ifdef FEAT_SYN_HL
2403     // Free independent synblock before the buffer is freed.
2404     if (win->w_buffer != NULL)
2405 	reset_synblock(win);
2406 #endif
2407 
2408 #ifdef FEAT_QUICKFIX
2409     // When the quickfix/location list window is closed, unlist the buffer.
2410     if (win->w_buffer != NULL && bt_quickfix(win->w_buffer))
2411 	win->w_buffer->b_p_bl = FALSE;
2412 #endif
2413 
2414     // Close the link to the buffer.
2415     if (win->w_buffer != NULL)
2416     {
2417 	bufref_T    bufref;
2418 
2419 	set_bufref(&bufref, curbuf);
2420 	win->w_closing = TRUE;
2421 	close_buffer(win, win->w_buffer, action, abort_if_last, FALSE);
2422 	if (win_valid_any_tab(win))
2423 	    win->w_closing = FALSE;
2424 	// Make sure curbuf is valid. It can become invalid if 'bufhidden' is
2425 	// "wipe".
2426 	if (!bufref_valid(&bufref))
2427 	    curbuf = firstbuf;
2428     }
2429 }
2430 
2431 /*
2432  * Close window "win".  Only works for the current tab page.
2433  * If "free_buf" is TRUE related buffer may be unloaded.
2434  *
2435  * Called by :quit, :close, :xit, :wq and findtag().
2436  * Returns FAIL when the window was not closed.
2437  */
2438     int
2439 win_close(win_T *win, int free_buf)
2440 {
2441     win_T	*wp;
2442     int		other_buffer = FALSE;
2443     int		close_curwin = FALSE;
2444     int		dir;
2445     int		help_window = FALSE;
2446     tabpage_T   *prev_curtab = curtab;
2447     frame_T	*win_frame = win->w_frame->fr_parent;
2448 #ifdef FEAT_DIFF
2449     int		had_diffmode = win->w_p_diff;
2450 #endif
2451 
2452 #if defined(FEAT_TERMINAL) && defined(FEAT_PROP_POPUP)
2453     // Can close a popup window with a terminal if the job has finished.
2454     if (may_close_term_popup() == OK)
2455 	return OK;
2456 #endif
2457     if (ERROR_IF_ANY_POPUP_WINDOW)
2458 	return FAIL;
2459 
2460     if (last_window())
2461     {
2462 	emsg(_("E444: Cannot close last window"));
2463 	return FAIL;
2464     }
2465 
2466     if (win->w_closing || (win->w_buffer != NULL
2467 					       && win->w_buffer->b_locked > 0))
2468 	return FAIL; // window is already being closed
2469     if (win_unlisted(win))
2470     {
2471 	emsg(_(e_autocmd_close));
2472 	return FAIL;
2473     }
2474     if ((firstwin == aucmd_win || lastwin == aucmd_win) && one_window())
2475     {
2476 	emsg(_("E814: Cannot close window, only autocmd window would remain"));
2477 	return FAIL;
2478     }
2479 
2480     // When closing the last window in a tab page first go to another tab page
2481     // and then close the window and the tab page to avoid that curwin and
2482     // curtab are invalid while we are freeing memory.
2483     if (close_last_window_tabpage(win, free_buf, prev_curtab))
2484       return FAIL;
2485 
2486     // When closing the help window, try restoring a snapshot after closing
2487     // the window.  Otherwise clear the snapshot, it's now invalid.
2488     if (bt_help(win->w_buffer))
2489 	help_window = TRUE;
2490     else
2491 	clear_snapshot(curtab, SNAP_HELP_IDX);
2492 
2493     if (win == curwin)
2494     {
2495 #ifdef FEAT_JOB_CHANNEL
2496 	leaving_window(curwin);
2497 #endif
2498 	/*
2499 	 * Guess which window is going to be the new current window.
2500 	 * This may change because of the autocommands (sigh).
2501 	 */
2502 	wp = frame2win(win_altframe(win, NULL));
2503 
2504 	/*
2505 	 * Be careful: If autocommands delete the window or cause this window
2506 	 * to be the last one left, return now.
2507 	 */
2508 	if (wp->w_buffer != curbuf)
2509 	{
2510 	    other_buffer = TRUE;
2511 	    win->w_closing = TRUE;
2512 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
2513 	    if (!win_valid(win))
2514 		return FAIL;
2515 	    win->w_closing = FALSE;
2516 	    if (last_window())
2517 		return FAIL;
2518 	}
2519 	win->w_closing = TRUE;
2520 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
2521 	if (!win_valid(win))
2522 	    return FAIL;
2523 	win->w_closing = FALSE;
2524 	if (last_window())
2525 	    return FAIL;
2526 #ifdef FEAT_EVAL
2527 	// autocmds may abort script processing
2528 	if (aborting())
2529 	    return FAIL;
2530 #endif
2531     }
2532 
2533 #ifdef FEAT_GUI
2534     // Avoid trouble with scrollbars that are going to be deleted in
2535     // win_free().
2536     if (gui.in_use)
2537 	out_flush();
2538 #endif
2539 
2540 #ifdef FEAT_PROP_POPUP
2541     if (popup_win_closed(win) && !win_valid(win))
2542 	return FAIL;
2543 #endif
2544     win_close_buffer(win, free_buf ? DOBUF_UNLOAD : 0, TRUE);
2545 
2546     if (only_one_window() && win_valid(win) && win->w_buffer == NULL
2547 	    && (last_window() || curtab != prev_curtab
2548 		|| close_last_window_tabpage(win, free_buf, prev_curtab)))
2549     {
2550 	// Autocommands have closed all windows, quit now.  Restore
2551 	// curwin->w_buffer, otherwise writing viminfo may fail.
2552 	if (curwin->w_buffer == NULL)
2553 	    curwin->w_buffer = curbuf;
2554 	getout(0);
2555     }
2556 
2557     // Autocommands may have moved to another tab page.
2558     if (curtab != prev_curtab && win_valid_any_tab(win)
2559 						      && win->w_buffer == NULL)
2560     {
2561 	// Need to close the window anyway, since the buffer is NULL.
2562 	win_close_othertab(win, FALSE, prev_curtab);
2563 	return FAIL;
2564     }
2565 
2566     // Autocommands may have closed the window already or closed the only
2567     // other window.
2568     if (!win_valid(win) || last_window()
2569 	    || close_last_window_tabpage(win, free_buf, prev_curtab))
2570 	return FAIL;
2571 
2572     // Now we are really going to close the window.  Disallow any autocommand
2573     // to split a window to avoid trouble.
2574     ++split_disallowed;
2575 
2576     // Free the memory used for the window and get the window that received
2577     // the screen space.
2578     wp = win_free_mem(win, &dir, NULL);
2579 
2580     // Make sure curwin isn't invalid.  It can cause severe trouble when
2581     // printing an error message.  For win_equal() curbuf needs to be valid
2582     // too.
2583     if (win == curwin)
2584     {
2585 	curwin = wp;
2586 #ifdef FEAT_QUICKFIX
2587 	if (wp->w_p_pvw || bt_quickfix(wp->w_buffer))
2588 	{
2589 	    /*
2590 	     * If the cursor goes to the preview or the quickfix window, try
2591 	     * finding another window to go to.
2592 	     */
2593 	    for (;;)
2594 	    {
2595 		if (wp->w_next == NULL)
2596 		    wp = firstwin;
2597 		else
2598 		    wp = wp->w_next;
2599 		if (wp == curwin)
2600 		    break;
2601 		if (!wp->w_p_pvw && !bt_quickfix(wp->w_buffer))
2602 		{
2603 		    curwin = wp;
2604 		    break;
2605 		}
2606 	    }
2607 	}
2608 #endif
2609 	curbuf = curwin->w_buffer;
2610 	close_curwin = TRUE;
2611 
2612 	// The cursor position may be invalid if the buffer changed after last
2613 	// using the window.
2614 	check_cursor();
2615     }
2616     if (p_ea && (*p_ead == 'b' || *p_ead == dir))
2617 	// If the frame of the closed window contains the new current window,
2618 	// only resize that frame.  Otherwise resize all windows.
2619 	win_equal(curwin, curwin->w_frame->fr_parent == win_frame, dir);
2620     else
2621 	win_comp_pos();
2622     if (close_curwin)
2623     {
2624 	win_enter_ext(wp, FALSE, TRUE, FALSE, TRUE, TRUE);
2625 	if (other_buffer)
2626 	    // careful: after this wp and win may be invalid!
2627 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2628     }
2629 
2630     --split_disallowed;
2631 
2632     /*
2633      * If last window has a status line now and we don't want one,
2634      * remove the status line.
2635      */
2636     last_status(FALSE);
2637 
2638     // After closing the help window, try restoring the window layout from
2639     // before it was opened.
2640     if (help_window)
2641 	restore_snapshot(SNAP_HELP_IDX, close_curwin);
2642 
2643 #ifdef FEAT_DIFF
2644     // If the window had 'diff' set and now there is only one window left in
2645     // the tab page with 'diff' set, and "closeoff" is in 'diffopt', then
2646     // execute ":diffoff!".
2647     if (diffopt_closeoff() && had_diffmode && curtab == prev_curtab)
2648     {
2649 	int	diffcount = 0;
2650 	win_T	*dwin;
2651 
2652 	FOR_ALL_WINDOWS(dwin)
2653 	    if (dwin->w_p_diff)
2654 		++diffcount;
2655 	if (diffcount == 1)
2656 	    do_cmdline_cmd((char_u *)"diffoff!");
2657     }
2658 #endif
2659 
2660 #if defined(FEAT_GUI)
2661     // When 'guioptions' includes 'L' or 'R' may have to remove scrollbars.
2662     if (gui.in_use && !win_hasvertsplit())
2663 	gui_init_which_components(NULL);
2664 #endif
2665 
2666     redraw_all_later(NOT_VALID);
2667     return OK;
2668 }
2669 
2670 /*
2671  * Close window "win" in tab page "tp", which is not the current tab page.
2672  * This may be the last window in that tab page and result in closing the tab,
2673  * thus "tp" may become invalid!
2674  * Caller must check if buffer is hidden and whether the tabline needs to be
2675  * updated.
2676  */
2677     void
2678 win_close_othertab(win_T *win, int free_buf, tabpage_T *tp)
2679 {
2680     win_T	*wp;
2681     int		dir;
2682     tabpage_T   *ptp = NULL;
2683     int		free_tp = FALSE;
2684 
2685     // Get here with win->w_buffer == NULL when win_close() detects the tab
2686     // page changed.
2687     if (win->w_closing || (win->w_buffer != NULL
2688 					       && win->w_buffer->b_locked > 0))
2689 	return; // window is already being closed
2690 
2691     if (win->w_buffer != NULL)
2692 	// Close the link to the buffer.
2693 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0,
2694 								 FALSE, FALSE);
2695 
2696     // Careful: Autocommands may have closed the tab page or made it the
2697     // current tab page.
2698     for (ptp = first_tabpage; ptp != NULL && ptp != tp; ptp = ptp->tp_next)
2699 	;
2700     if (ptp == NULL || tp == curtab)
2701 	return;
2702 
2703     // Autocommands may have closed the window already.
2704     for (wp = tp->tp_firstwin; wp != NULL && wp != win; wp = wp->w_next)
2705 	;
2706     if (wp == NULL)
2707 	return;
2708 
2709     // When closing the last window in a tab page remove the tab page.
2710     if (tp->tp_firstwin == tp->tp_lastwin)
2711     {
2712 	if (tp == first_tabpage)
2713 	    first_tabpage = tp->tp_next;
2714 	else
2715 	{
2716 	    for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tp;
2717 							   ptp = ptp->tp_next)
2718 		;
2719 	    if (ptp == NULL)
2720 	    {
2721 		internal_error("win_close_othertab()");
2722 		return;
2723 	    }
2724 	    ptp->tp_next = tp->tp_next;
2725 	}
2726 	free_tp = TRUE;
2727     }
2728 
2729     // Free the memory used for the window.
2730     win_free_mem(win, &dir, tp);
2731 
2732     if (free_tp)
2733 	free_tabpage(tp);
2734 }
2735 
2736 /*
2737  * Free the memory used for a window.
2738  * Returns a pointer to the window that got the freed up space.
2739  */
2740     static win_T *
2741 win_free_mem(
2742     win_T	*win,
2743     int		*dirp,		// set to 'v' or 'h' for direction if 'ea'
2744     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2745 {
2746     frame_T	*frp;
2747     win_T	*wp;
2748 
2749     // Remove the window and its frame from the tree of frames.
2750     frp = win->w_frame;
2751     wp = winframe_remove(win, dirp, tp);
2752     vim_free(frp);
2753     win_free(win, tp);
2754 
2755     // When deleting the current window of another tab page select a new
2756     // current window.
2757     if (tp != NULL && win == tp->tp_curwin)
2758 	tp->tp_curwin = wp;
2759 
2760     return wp;
2761 }
2762 
2763 #if defined(EXITFREE) || defined(PROTO)
2764     void
2765 win_free_all(void)
2766 {
2767     int		dummy;
2768 
2769     while (first_tabpage->tp_next != NULL)
2770 	tabpage_close(TRUE);
2771 
2772     if (aucmd_win != NULL)
2773     {
2774 	(void)win_free_mem(aucmd_win, &dummy, NULL);
2775 	aucmd_win = NULL;
2776     }
2777 
2778     while (firstwin != NULL)
2779 	(void)win_free_mem(firstwin, &dummy, NULL);
2780 
2781     // No window should be used after this. Set curwin to NULL to crash
2782     // instead of using freed memory.
2783     curwin = NULL;
2784 }
2785 #endif
2786 
2787 /*
2788  * Remove a window and its frame from the tree of frames.
2789  * Returns a pointer to the window that got the freed up space.
2790  */
2791     win_T *
2792 winframe_remove(
2793     win_T	*win,
2794     int		*dirp UNUSED,	// set to 'v' or 'h' for direction if 'ea'
2795     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2796 {
2797     frame_T	*frp, *frp2, *frp3;
2798     frame_T	*frp_close = win->w_frame;
2799     win_T	*wp;
2800 
2801     /*
2802      * If there is only one window there is nothing to remove.
2803      */
2804     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2805 	return NULL;
2806 
2807     /*
2808      * Remove the window from its frame.
2809      */
2810     frp2 = win_altframe(win, tp);
2811     wp = frame2win(frp2);
2812 
2813     // Remove this frame from the list of frames.
2814     frame_remove(frp_close);
2815 
2816     if (frp_close->fr_parent->fr_layout == FR_COL)
2817     {
2818 	// When 'winfixheight' is set, try to find another frame in the column
2819 	// (as close to the closed frame as possible) to distribute the height
2820 	// to.
2821 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfh)
2822 	{
2823 	    frp = frp_close->fr_prev;
2824 	    frp3 = frp_close->fr_next;
2825 	    while (frp != NULL || frp3 != NULL)
2826 	    {
2827 		if (frp != NULL)
2828 		{
2829 		    if (!frame_fixed_height(frp))
2830 		    {
2831 			frp2 = frp;
2832 			wp = frame2win(frp2);
2833 			break;
2834 		    }
2835 		    frp = frp->fr_prev;
2836 		}
2837 		if (frp3 != NULL)
2838 		{
2839 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfh)
2840 		    {
2841 			frp2 = frp3;
2842 			wp = frp3->fr_win;
2843 			break;
2844 		    }
2845 		    frp3 = frp3->fr_next;
2846 		}
2847 	    }
2848 	}
2849 	frame_new_height(frp2, frp2->fr_height + frp_close->fr_height,
2850 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2851 	*dirp = 'v';
2852     }
2853     else
2854     {
2855 	// When 'winfixwidth' is set, try to find another frame in the column
2856 	// (as close to the closed frame as possible) to distribute the width
2857 	// to.
2858 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfw)
2859 	{
2860 	    frp = frp_close->fr_prev;
2861 	    frp3 = frp_close->fr_next;
2862 	    while (frp != NULL || frp3 != NULL)
2863 	    {
2864 		if (frp != NULL)
2865 		{
2866 		    if (!frame_fixed_width(frp))
2867 		    {
2868 			frp2 = frp;
2869 			wp = frame2win(frp2);
2870 			break;
2871 		    }
2872 		    frp = frp->fr_prev;
2873 		}
2874 		if (frp3 != NULL)
2875 		{
2876 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfw)
2877 		    {
2878 			frp2 = frp3;
2879 			wp = frp3->fr_win;
2880 			break;
2881 		    }
2882 		    frp3 = frp3->fr_next;
2883 		}
2884 	    }
2885 	}
2886 	frame_new_width(frp2, frp2->fr_width + frp_close->fr_width,
2887 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2888 	*dirp = 'h';
2889     }
2890 
2891     // If rows/columns go to a window below/right its positions need to be
2892     // updated.  Can only be done after the sizes have been updated.
2893     if (frp2 == frp_close->fr_next)
2894     {
2895 	int row = win->w_winrow;
2896 	int col = win->w_wincol;
2897 
2898 	frame_comp_pos(frp2, &row, &col);
2899     }
2900 
2901     if (frp2->fr_next == NULL && frp2->fr_prev == NULL)
2902     {
2903 	// There is no other frame in this list, move its info to the parent
2904 	// and remove it.
2905 	frp2->fr_parent->fr_layout = frp2->fr_layout;
2906 	frp2->fr_parent->fr_child = frp2->fr_child;
2907 	FOR_ALL_FRAMES(frp, frp2->fr_child)
2908 	    frp->fr_parent = frp2->fr_parent;
2909 	frp2->fr_parent->fr_win = frp2->fr_win;
2910 	if (frp2->fr_win != NULL)
2911 	    frp2->fr_win->w_frame = frp2->fr_parent;
2912 	frp = frp2->fr_parent;
2913 	if (topframe->fr_child == frp2)
2914 	    topframe->fr_child = frp;
2915 	vim_free(frp2);
2916 
2917 	frp2 = frp->fr_parent;
2918 	if (frp2 != NULL && frp2->fr_layout == frp->fr_layout)
2919 	{
2920 	    // The frame above the parent has the same layout, have to merge
2921 	    // the frames into this list.
2922 	    if (frp2->fr_child == frp)
2923 		frp2->fr_child = frp->fr_child;
2924 	    frp->fr_child->fr_prev = frp->fr_prev;
2925 	    if (frp->fr_prev != NULL)
2926 		frp->fr_prev->fr_next = frp->fr_child;
2927 	    for (frp3 = frp->fr_child; ; frp3 = frp3->fr_next)
2928 	    {
2929 		frp3->fr_parent = frp2;
2930 		if (frp3->fr_next == NULL)
2931 		{
2932 		    frp3->fr_next = frp->fr_next;
2933 		    if (frp->fr_next != NULL)
2934 			frp->fr_next->fr_prev = frp3;
2935 		    break;
2936 		}
2937 	    }
2938 	    if (topframe->fr_child == frp)
2939 		topframe->fr_child = frp2;
2940 	    vim_free(frp);
2941 	}
2942     }
2943 
2944     return wp;
2945 }
2946 
2947 /*
2948  * Return a pointer to the frame that will receive the empty screen space that
2949  * is left over after "win" is closed.
2950  *
2951  * If 'splitbelow' or 'splitright' is set, the space goes above or to the left
2952  * by default.  Otherwise, the free space goes below or to the right.  The
2953  * result is that opening a window and then immediately closing it will
2954  * preserve the initial window layout.  The 'wfh' and 'wfw' settings are
2955  * respected when possible.
2956  */
2957     static frame_T *
2958 win_altframe(
2959     win_T	*win,
2960     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2961 {
2962     frame_T	*frp;
2963     frame_T	*other_fr, *target_fr;
2964 
2965     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2966 	return alt_tabpage()->tp_curwin->w_frame;
2967 
2968     frp = win->w_frame;
2969 
2970     if (frp->fr_prev == NULL)
2971 	return frp->fr_next;
2972     if (frp->fr_next == NULL)
2973 	return frp->fr_prev;
2974 
2975     // By default the next window will get the space that was abandoned by this
2976     // window
2977     target_fr = frp->fr_next;
2978     other_fr  = frp->fr_prev;
2979 
2980     // If this is part of a column of windows and 'splitbelow' is true then the
2981     // previous window will get the space.
2982     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_COL && p_sb)
2983     {
2984 	target_fr = frp->fr_prev;
2985 	other_fr  = frp->fr_next;
2986     }
2987 
2988     // If this is part of a row of windows, and 'splitright' is true then the
2989     // previous window will get the space.
2990     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW && p_spr)
2991     {
2992 	target_fr = frp->fr_prev;
2993 	other_fr  = frp->fr_next;
2994     }
2995 
2996     // If 'wfh' or 'wfw' is set for the target and not for the alternate
2997     // window, reverse the selection.
2998     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW)
2999     {
3000 	if (frame_fixed_width(target_fr) && !frame_fixed_width(other_fr))
3001 	    target_fr = other_fr;
3002     }
3003     else
3004     {
3005 	if (frame_fixed_height(target_fr) && !frame_fixed_height(other_fr))
3006 	    target_fr = other_fr;
3007     }
3008 
3009     return target_fr;
3010 }
3011 
3012 /*
3013  * Return the tabpage that will be used if the current one is closed.
3014  */
3015     static tabpage_T *
3016 alt_tabpage(void)
3017 {
3018     tabpage_T	*tp;
3019 
3020     // Use the next tab page if possible.
3021     if (curtab->tp_next != NULL)
3022 	return curtab->tp_next;
3023 
3024     // Find the last but one tab page.
3025     for (tp = first_tabpage; tp->tp_next != curtab; tp = tp->tp_next)
3026 	;
3027     return tp;
3028 }
3029 
3030 /*
3031  * Find the left-upper window in frame "frp".
3032  */
3033     static win_T *
3034 frame2win(frame_T *frp)
3035 {
3036     while (frp->fr_win == NULL)
3037 	frp = frp->fr_child;
3038     return frp->fr_win;
3039 }
3040 
3041 /*
3042  * Return TRUE if frame "frp" contains window "wp".
3043  */
3044     static int
3045 frame_has_win(frame_T *frp, win_T *wp)
3046 {
3047     frame_T	*p;
3048 
3049     if (frp->fr_layout == FR_LEAF)
3050 	return frp->fr_win == wp;
3051 
3052     FOR_ALL_FRAMES(p, frp->fr_child)
3053 	if (frame_has_win(p, wp))
3054 	    return TRUE;
3055     return FALSE;
3056 }
3057 
3058 /*
3059  * Set a new height for a frame.  Recursively sets the height for contained
3060  * frames and windows.  Caller must take care of positions.
3061  */
3062     static void
3063 frame_new_height(
3064     frame_T	*topfrp,
3065     int		height,
3066     int		topfirst,	// resize topmost contained frame first
3067     int		wfh)		// obey 'winfixheight' when there is a choice;
3068 				// may cause the height not to be set
3069 {
3070     frame_T	*frp;
3071     int		extra_lines;
3072     int		h;
3073 
3074     if (topfrp->fr_win != NULL)
3075     {
3076 	// Simple case: just one window.
3077 	win_new_height(topfrp->fr_win,
3078 				    height - topfrp->fr_win->w_status_height
3079 					      - WINBAR_HEIGHT(topfrp->fr_win));
3080     }
3081     else if (topfrp->fr_layout == FR_ROW)
3082     {
3083 	do
3084 	{
3085 	    // All frames in this row get the same new height.
3086 	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
3087 	    {
3088 		frame_new_height(frp, height, topfirst, wfh);
3089 		if (frp->fr_height > height)
3090 		{
3091 		    // Could not fit the windows, make the whole row higher.
3092 		    height = frp->fr_height;
3093 		    break;
3094 		}
3095 	    }
3096 	}
3097 	while (frp != NULL);
3098     }
3099     else    // fr_layout == FR_COL
3100     {
3101 	// Complicated case: Resize a column of frames.  Resize the bottom
3102 	// frame first, frames above that when needed.
3103 
3104 	frp = topfrp->fr_child;
3105 	if (wfh)
3106 	    // Advance past frames with one window with 'wfh' set.
3107 	    while (frame_fixed_height(frp))
3108 	    {
3109 		frp = frp->fr_next;
3110 		if (frp == NULL)
3111 		    return;	    // no frame without 'wfh', give up
3112 	    }
3113 	if (!topfirst)
3114 	{
3115 	    // Find the bottom frame of this column
3116 	    while (frp->fr_next != NULL)
3117 		frp = frp->fr_next;
3118 	    if (wfh)
3119 		// Advance back for frames with one window with 'wfh' set.
3120 		while (frame_fixed_height(frp))
3121 		    frp = frp->fr_prev;
3122 	}
3123 
3124 	extra_lines = height - topfrp->fr_height;
3125 	if (extra_lines < 0)
3126 	{
3127 	    // reduce height of contained frames, bottom or top frame first
3128 	    while (frp != NULL)
3129 	    {
3130 		h = frame_minheight(frp, NULL);
3131 		if (frp->fr_height + extra_lines < h)
3132 		{
3133 		    extra_lines += frp->fr_height - h;
3134 		    frame_new_height(frp, h, topfirst, wfh);
3135 		}
3136 		else
3137 		{
3138 		    frame_new_height(frp, frp->fr_height + extra_lines,
3139 							       topfirst, wfh);
3140 		    break;
3141 		}
3142 		if (topfirst)
3143 		{
3144 		    do
3145 			frp = frp->fr_next;
3146 		    while (wfh && frp != NULL && frame_fixed_height(frp));
3147 		}
3148 		else
3149 		{
3150 		    do
3151 			frp = frp->fr_prev;
3152 		    while (wfh && frp != NULL && frame_fixed_height(frp));
3153 		}
3154 		// Increase "height" if we could not reduce enough frames.
3155 		if (frp == NULL)
3156 		    height -= extra_lines;
3157 	    }
3158 	}
3159 	else if (extra_lines > 0)
3160 	{
3161 	    // increase height of bottom or top frame
3162 	    frame_new_height(frp, frp->fr_height + extra_lines, topfirst, wfh);
3163 	}
3164     }
3165     topfrp->fr_height = height;
3166 }
3167 
3168 /*
3169  * Return TRUE if height of frame "frp" should not be changed because of
3170  * the 'winfixheight' option.
3171  */
3172     static int
3173 frame_fixed_height(frame_T *frp)
3174 {
3175     // frame with one window: fixed height if 'winfixheight' set.
3176     if (frp->fr_win != NULL)
3177 	return frp->fr_win->w_p_wfh;
3178 
3179     if (frp->fr_layout == FR_ROW)
3180     {
3181 	// The frame is fixed height if one of the frames in the row is fixed
3182 	// height.
3183 	FOR_ALL_FRAMES(frp, frp->fr_child)
3184 	    if (frame_fixed_height(frp))
3185 		return TRUE;
3186 	return FALSE;
3187     }
3188 
3189     // frp->fr_layout == FR_COL: The frame is fixed height if all of the
3190     // frames in the row are fixed height.
3191     FOR_ALL_FRAMES(frp, frp->fr_child)
3192 	if (!frame_fixed_height(frp))
3193 	    return FALSE;
3194     return TRUE;
3195 }
3196 
3197 /*
3198  * Return TRUE if width of frame "frp" should not be changed because of
3199  * the 'winfixwidth' option.
3200  */
3201     static int
3202 frame_fixed_width(frame_T *frp)
3203 {
3204     // frame with one window: fixed width if 'winfixwidth' set.
3205     if (frp->fr_win != NULL)
3206 	return frp->fr_win->w_p_wfw;
3207 
3208     if (frp->fr_layout == FR_COL)
3209     {
3210 	// The frame is fixed width if one of the frames in the row is fixed
3211 	// width.
3212 	FOR_ALL_FRAMES(frp, frp->fr_child)
3213 	    if (frame_fixed_width(frp))
3214 		return TRUE;
3215 	return FALSE;
3216     }
3217 
3218     // frp->fr_layout == FR_ROW: The frame is fixed width if all of the
3219     // frames in the row are fixed width.
3220     FOR_ALL_FRAMES(frp, frp->fr_child)
3221 	if (!frame_fixed_width(frp))
3222 	    return FALSE;
3223     return TRUE;
3224 }
3225 
3226 /*
3227  * Add a status line to windows at the bottom of "frp".
3228  * Note: Does not check if there is room!
3229  */
3230     static void
3231 frame_add_statusline(frame_T *frp)
3232 {
3233     win_T	*wp;
3234 
3235     if (frp->fr_layout == FR_LEAF)
3236     {
3237 	wp = frp->fr_win;
3238 	if (wp->w_status_height == 0)
3239 	{
3240 	    if (wp->w_height > 0)	// don't make it negative
3241 		--wp->w_height;
3242 	    wp->w_status_height = STATUS_HEIGHT;
3243 	}
3244     }
3245     else if (frp->fr_layout == FR_ROW)
3246     {
3247 	// Handle all the frames in the row.
3248 	FOR_ALL_FRAMES(frp, frp->fr_child)
3249 	    frame_add_statusline(frp);
3250     }
3251     else // frp->fr_layout == FR_COL
3252     {
3253 	// Only need to handle the last frame in the column.
3254 	for (frp = frp->fr_child; frp->fr_next != NULL; frp = frp->fr_next)
3255 	    ;
3256 	frame_add_statusline(frp);
3257     }
3258 }
3259 
3260 /*
3261  * Set width of a frame.  Handles recursively going through contained frames.
3262  * May remove separator line for windows at the right side (for win_close()).
3263  */
3264     static void
3265 frame_new_width(
3266     frame_T	*topfrp,
3267     int		width,
3268     int		leftfirst,	// resize leftmost contained frame first
3269     int		wfw)		// obey 'winfixwidth' when there is a choice;
3270 				// may cause the width not to be set
3271 {
3272     frame_T	*frp;
3273     int		extra_cols;
3274     int		w;
3275     win_T	*wp;
3276 
3277     if (topfrp->fr_layout == FR_LEAF)
3278     {
3279 	// Simple case: just one window.
3280 	wp = topfrp->fr_win;
3281 	// Find out if there are any windows right of this one.
3282 	for (frp = topfrp; frp->fr_parent != NULL; frp = frp->fr_parent)
3283 	    if (frp->fr_parent->fr_layout == FR_ROW && frp->fr_next != NULL)
3284 		break;
3285 	if (frp->fr_parent == NULL)
3286 	    wp->w_vsep_width = 0;
3287 	win_new_width(wp, width - wp->w_vsep_width);
3288     }
3289     else if (topfrp->fr_layout == FR_COL)
3290     {
3291 	do
3292 	{
3293 	    // All frames in this column get the same new width.
3294 	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
3295 	    {
3296 		frame_new_width(frp, width, leftfirst, wfw);
3297 		if (frp->fr_width > width)
3298 		{
3299 		    // Could not fit the windows, make whole column wider.
3300 		    width = frp->fr_width;
3301 		    break;
3302 		}
3303 	    }
3304 	} while (frp != NULL);
3305     }
3306     else    // fr_layout == FR_ROW
3307     {
3308 	// Complicated case: Resize a row of frames.  Resize the rightmost
3309 	// frame first, frames left of it when needed.
3310 
3311 	frp = topfrp->fr_child;
3312 	if (wfw)
3313 	    // Advance past frames with one window with 'wfw' set.
3314 	    while (frame_fixed_width(frp))
3315 	    {
3316 		frp = frp->fr_next;
3317 		if (frp == NULL)
3318 		    return;	    // no frame without 'wfw', give up
3319 	    }
3320 	if (!leftfirst)
3321 	{
3322 	    // Find the rightmost frame of this row
3323 	    while (frp->fr_next != NULL)
3324 		frp = frp->fr_next;
3325 	    if (wfw)
3326 		// Advance back for frames with one window with 'wfw' set.
3327 		while (frame_fixed_width(frp))
3328 		    frp = frp->fr_prev;
3329 	}
3330 
3331 	extra_cols = width - topfrp->fr_width;
3332 	if (extra_cols < 0)
3333 	{
3334 	    // reduce frame width, rightmost frame first
3335 	    while (frp != NULL)
3336 	    {
3337 		w = frame_minwidth(frp, NULL);
3338 		if (frp->fr_width + extra_cols < w)
3339 		{
3340 		    extra_cols += frp->fr_width - w;
3341 		    frame_new_width(frp, w, leftfirst, wfw);
3342 		}
3343 		else
3344 		{
3345 		    frame_new_width(frp, frp->fr_width + extra_cols,
3346 							      leftfirst, wfw);
3347 		    break;
3348 		}
3349 		if (leftfirst)
3350 		{
3351 		    do
3352 			frp = frp->fr_next;
3353 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3354 		}
3355 		else
3356 		{
3357 		    do
3358 			frp = frp->fr_prev;
3359 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3360 		}
3361 		// Increase "width" if we could not reduce enough frames.
3362 		if (frp == NULL)
3363 		    width -= extra_cols;
3364 	    }
3365 	}
3366 	else if (extra_cols > 0)
3367 	{
3368 	    // increase width of rightmost frame
3369 	    frame_new_width(frp, frp->fr_width + extra_cols, leftfirst, wfw);
3370 	}
3371     }
3372     topfrp->fr_width = width;
3373 }
3374 
3375 /*
3376  * Add the vertical separator to windows at the right side of "frp".
3377  * Note: Does not check if there is room!
3378  */
3379     static void
3380 frame_add_vsep(frame_T *frp)
3381 {
3382     win_T	*wp;
3383 
3384     if (frp->fr_layout == FR_LEAF)
3385     {
3386 	wp = frp->fr_win;
3387 	if (wp->w_vsep_width == 0)
3388 	{
3389 	    if (wp->w_width > 0)	// don't make it negative
3390 		--wp->w_width;
3391 	    wp->w_vsep_width = 1;
3392 	}
3393     }
3394     else if (frp->fr_layout == FR_COL)
3395     {
3396 	// Handle all the frames in the column.
3397 	FOR_ALL_FRAMES(frp, frp->fr_child)
3398 	    frame_add_vsep(frp);
3399     }
3400     else // frp->fr_layout == FR_ROW
3401     {
3402 	// Only need to handle the last frame in the row.
3403 	frp = frp->fr_child;
3404 	while (frp->fr_next != NULL)
3405 	    frp = frp->fr_next;
3406 	frame_add_vsep(frp);
3407     }
3408 }
3409 
3410 /*
3411  * Set frame width from the window it contains.
3412  */
3413     static void
3414 frame_fix_width(win_T *wp)
3415 {
3416     wp->w_frame->fr_width = wp->w_width + wp->w_vsep_width;
3417 }
3418 
3419 /*
3420  * Set frame height from the window it contains.
3421  */
3422     static void
3423 frame_fix_height(win_T *wp)
3424 {
3425     wp->w_frame->fr_height = VISIBLE_HEIGHT(wp) + wp->w_status_height;
3426 }
3427 
3428 /*
3429  * Compute the minimal height for frame "topfrp".
3430  * Uses the 'winminheight' option.
3431  * When "next_curwin" isn't NULL, use p_wh for this window.
3432  * When "next_curwin" is NOWIN, don't use at least one line for the current
3433  * window.
3434  */
3435     static int
3436 frame_minheight(frame_T *topfrp, win_T *next_curwin)
3437 {
3438     frame_T	*frp;
3439     int		m;
3440     int		n;
3441 
3442     if (topfrp->fr_win != NULL)
3443     {
3444 	if (topfrp->fr_win == next_curwin)
3445 	    m = p_wh + topfrp->fr_win->w_status_height;
3446 	else
3447 	{
3448 	    // window: minimal height of the window plus status line
3449 	    m = p_wmh + topfrp->fr_win->w_status_height;
3450 	    if (topfrp->fr_win == curwin && next_curwin == NULL)
3451 	    {
3452 		// Current window is minimal one line high and WinBar is
3453 		// visible.
3454 		if (p_wmh == 0)
3455 		    ++m;
3456 		m += WINBAR_HEIGHT(curwin);
3457 	    }
3458 	}
3459     }
3460     else if (topfrp->fr_layout == FR_ROW)
3461     {
3462 	// get the minimal height from each frame in this row
3463 	m = 0;
3464 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3465 	{
3466 	    n = frame_minheight(frp, next_curwin);
3467 	    if (n > m)
3468 		m = n;
3469 	}
3470     }
3471     else
3472     {
3473 	// Add up the minimal heights for all frames in this column.
3474 	m = 0;
3475 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3476 	    m += frame_minheight(frp, next_curwin);
3477     }
3478 
3479     return m;
3480 }
3481 
3482 /*
3483  * Compute the minimal width for frame "topfrp".
3484  * When "next_curwin" isn't NULL, use p_wiw for this window.
3485  * When "next_curwin" is NOWIN, don't use at least one column for the current
3486  * window.
3487  */
3488     static int
3489 frame_minwidth(
3490     frame_T	*topfrp,
3491     win_T	*next_curwin)	// use p_wh and p_wiw for next_curwin
3492 {
3493     frame_T	*frp;
3494     int		m, n;
3495 
3496     if (topfrp->fr_win != NULL)
3497     {
3498 	if (topfrp->fr_win == next_curwin)
3499 	    m = p_wiw + topfrp->fr_win->w_vsep_width;
3500 	else
3501 	{
3502 	    // window: minimal width of the window plus separator column
3503 	    m = p_wmw + topfrp->fr_win->w_vsep_width;
3504 	    // Current window is minimal one column wide
3505 	    if (p_wmw == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3506 		++m;
3507 	}
3508     }
3509     else if (topfrp->fr_layout == FR_COL)
3510     {
3511 	// get the minimal width from each frame in this column
3512 	m = 0;
3513 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3514 	{
3515 	    n = frame_minwidth(frp, next_curwin);
3516 	    if (n > m)
3517 		m = n;
3518 	}
3519     }
3520     else
3521     {
3522 	// Add up the minimal widths for all frames in this row.
3523 	m = 0;
3524 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3525 	    m += frame_minwidth(frp, next_curwin);
3526     }
3527 
3528     return m;
3529 }
3530 
3531 
3532 /*
3533  * Try to close all windows except current one.
3534  * Buffers in the other windows become hidden if 'hidden' is set, or '!' is
3535  * used and the buffer was modified.
3536  *
3537  * Used by ":bdel" and ":only".
3538  */
3539     void
3540 close_others(
3541     int		message,
3542     int		forceit)	    // always hide all other windows
3543 {
3544     win_T	*wp;
3545     win_T	*nextwp;
3546     int		r;
3547 
3548     if (one_window())
3549     {
3550 	if (message && !autocmd_busy)
3551 	    msg(_(m_onlyone));
3552 	return;
3553     }
3554 
3555     // Be very careful here: autocommands may change the window layout.
3556     for (wp = firstwin; win_valid(wp); wp = nextwp)
3557     {
3558 	nextwp = wp->w_next;
3559 	if (wp != curwin)		// don't close current window
3560 	{
3561 
3562 	    // Check if it's allowed to abandon this window
3563 	    r = can_abandon(wp->w_buffer, forceit);
3564 	    if (!win_valid(wp))		// autocommands messed wp up
3565 	    {
3566 		nextwp = firstwin;
3567 		continue;
3568 	    }
3569 	    if (!r)
3570 	    {
3571 #if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
3572 		if (message && (p_confirm || cmdmod.confirm) && p_write)
3573 		{
3574 		    dialog_changed(wp->w_buffer, FALSE);
3575 		    if (!win_valid(wp))		// autocommands messed wp up
3576 		    {
3577 			nextwp = firstwin;
3578 			continue;
3579 		    }
3580 		}
3581 		if (bufIsChanged(wp->w_buffer))
3582 #endif
3583 		    continue;
3584 	    }
3585 	    win_close(wp, !buf_hide(wp->w_buffer)
3586 					       && !bufIsChanged(wp->w_buffer));
3587 	}
3588     }
3589 
3590     if (message && !ONE_WINDOW)
3591 	emsg(_("E445: Other window contains changes"));
3592 }
3593 
3594     static void
3595 win_init_empty(win_T *wp)
3596 {
3597     redraw_win_later(wp, NOT_VALID);
3598     wp->w_lines_valid = 0;
3599     wp->w_cursor.lnum = 1;
3600     wp->w_curswant = wp->w_cursor.col = 0;
3601     wp->w_cursor.coladd = 0;
3602     wp->w_pcmark.lnum = 1;	// pcmark not cleared but set to line 1
3603     wp->w_pcmark.col = 0;
3604     wp->w_prev_pcmark.lnum = 0;
3605     wp->w_prev_pcmark.col = 0;
3606     wp->w_topline = 1;
3607 #ifdef FEAT_DIFF
3608     wp->w_topfill = 0;
3609 #endif
3610     wp->w_botline = 2;
3611 #if defined(FEAT_SYN_HL) || defined(FEAT_SPELL)
3612     wp->w_s = &wp->w_buffer->b_s;
3613 #endif
3614 }
3615 
3616 /*
3617  * Init the current window "curwin".
3618  * Called when a new file is being edited.
3619  */
3620     void
3621 curwin_init(void)
3622 {
3623     win_init_empty(curwin);
3624 }
3625 
3626 /*
3627  * Allocate the first window and put an empty buffer in it.
3628  * Called from main().
3629  * Return FAIL when something goes wrong (out of memory).
3630  */
3631     int
3632 win_alloc_first(void)
3633 {
3634     if (win_alloc_firstwin(NULL) == FAIL)
3635 	return FAIL;
3636 
3637     first_tabpage = alloc_tabpage();
3638     if (first_tabpage == NULL)
3639 	return FAIL;
3640     first_tabpage->tp_topframe = topframe;
3641     curtab = first_tabpage;
3642     curtab->tp_firstwin = firstwin;
3643     curtab->tp_lastwin = lastwin;
3644     curtab->tp_curwin = curwin;
3645 
3646     return OK;
3647 }
3648 
3649 /*
3650  * Allocate and init a window that is not a regular window.
3651  * This can only be done after the first window is fully initialized, thus it
3652  * can't be in win_alloc_first().
3653  */
3654     win_T *
3655 win_alloc_popup_win(void)
3656 {
3657     win_T *wp;
3658 
3659     wp = win_alloc(NULL, TRUE);
3660     if (wp != NULL)
3661     {
3662 	// We need to initialize options with something, using the current
3663 	// window makes most sense.
3664 	win_init_some(wp, curwin);
3665 
3666 	RESET_BINDING(wp);
3667 	new_frame(wp);
3668     }
3669     return wp;
3670 }
3671 
3672 /*
3673  * Initialize window "wp" to display buffer "buf".
3674  */
3675     void
3676 win_init_popup_win(win_T *wp, buf_T *buf)
3677 {
3678     wp->w_buffer = buf;
3679     ++buf->b_nwindows;
3680     win_init_empty(wp); // set cursor and topline to safe values
3681 
3682     // Make sure w_localdir and globaldir are NULL to avoid a chdir() in
3683     // win_enter_ext().
3684     VIM_CLEAR(wp->w_localdir);
3685 }
3686 
3687 /*
3688  * Allocate the first window or the first window in a new tab page.
3689  * When "oldwin" is NULL create an empty buffer for it.
3690  * When "oldwin" is not NULL copy info from it to the new window.
3691  * Return FAIL when something goes wrong (out of memory).
3692  */
3693     static int
3694 win_alloc_firstwin(win_T *oldwin)
3695 {
3696     curwin = win_alloc(NULL, FALSE);
3697     if (oldwin == NULL)
3698     {
3699 	// Very first window, need to create an empty buffer for it and
3700 	// initialize from scratch.
3701 	curbuf = buflist_new(NULL, NULL, 1L, BLN_LISTED);
3702 	if (curwin == NULL || curbuf == NULL)
3703 	    return FAIL;
3704 	curwin->w_buffer = curbuf;
3705 #ifdef FEAT_SYN_HL
3706 	curwin->w_s = &(curbuf->b_s);
3707 #endif
3708 	curbuf->b_nwindows = 1;	// there is one window
3709 	curwin->w_alist = &global_alist;
3710 	curwin_init();		// init current window
3711     }
3712     else
3713     {
3714 	// First window in new tab page, initialize it from "oldwin".
3715 	win_init(curwin, oldwin, 0);
3716 
3717 	// We don't want cursor- and scroll-binding in the first window.
3718 	RESET_BINDING(curwin);
3719     }
3720 
3721     new_frame(curwin);
3722     if (curwin->w_frame == NULL)
3723 	return FAIL;
3724     topframe = curwin->w_frame;
3725     topframe->fr_width = Columns;
3726     topframe->fr_height = Rows - p_ch;
3727 
3728     return OK;
3729 }
3730 
3731 /*
3732  * Create a frame for window "wp".
3733  */
3734     static void
3735 new_frame(win_T *wp)
3736 {
3737     frame_T *frp = ALLOC_CLEAR_ONE(frame_T);
3738 
3739     wp->w_frame = frp;
3740     if (frp != NULL)
3741     {
3742 	frp->fr_layout = FR_LEAF;
3743 	frp->fr_win = wp;
3744     }
3745 }
3746 
3747 /*
3748  * Initialize the window and frame size to the maximum.
3749  */
3750     void
3751 win_init_size(void)
3752 {
3753     firstwin->w_height = ROWS_AVAIL;
3754     topframe->fr_height = ROWS_AVAIL;
3755     firstwin->w_width = Columns;
3756     topframe->fr_width = Columns;
3757 }
3758 
3759 /*
3760  * Allocate a new tabpage_T and init the values.
3761  * Returns NULL when out of memory.
3762  */
3763     static tabpage_T *
3764 alloc_tabpage(void)
3765 {
3766     tabpage_T	*tp;
3767 # ifdef FEAT_GUI
3768     int		i;
3769 # endif
3770 
3771 
3772     tp = ALLOC_CLEAR_ONE(tabpage_T);
3773     if (tp == NULL)
3774 	return NULL;
3775 
3776 # ifdef FEAT_EVAL
3777     // init t: variables
3778     tp->tp_vars = dict_alloc();
3779     if (tp->tp_vars == NULL)
3780     {
3781 	vim_free(tp);
3782 	return NULL;
3783     }
3784     init_var_dict(tp->tp_vars, &tp->tp_winvar, VAR_SCOPE);
3785 # endif
3786 
3787 # ifdef FEAT_GUI
3788     for (i = 0; i < 3; i++)
3789 	tp->tp_prev_which_scrollbars[i] = -1;
3790 # endif
3791 # ifdef FEAT_DIFF
3792     tp->tp_diff_invalid = TRUE;
3793 # endif
3794     tp->tp_ch_used = p_ch;
3795 
3796     return tp;
3797 }
3798 
3799     void
3800 free_tabpage(tabpage_T *tp)
3801 {
3802     int idx;
3803 
3804 # ifdef FEAT_DIFF
3805     diff_clear(tp);
3806 # endif
3807 # ifdef FEAT_PROP_POPUP
3808     while (tp->tp_first_popupwin != NULL)
3809 	popup_close_tabpage(tp, tp->tp_first_popupwin->w_id, TRUE);
3810 #endif
3811     for (idx = 0; idx < SNAP_COUNT; ++idx)
3812 	clear_snapshot(tp, idx);
3813 #ifdef FEAT_EVAL
3814     vars_clear(&tp->tp_vars->dv_hashtab);	// free all t: variables
3815     hash_init(&tp->tp_vars->dv_hashtab);
3816     unref_var_dict(tp->tp_vars);
3817 #endif
3818 
3819     if (tp == lastused_tabpage)
3820 	lastused_tabpage = NULL;
3821 
3822     vim_free(tp->tp_localdir);
3823     vim_free(tp->tp_prevdir);
3824 
3825 #ifdef FEAT_PYTHON
3826     python_tabpage_free(tp);
3827 #endif
3828 
3829 #ifdef FEAT_PYTHON3
3830     python3_tabpage_free(tp);
3831 #endif
3832 
3833     vim_free(tp);
3834 }
3835 
3836 /*
3837  * Create a new Tab page with one window.
3838  * It will edit the current buffer, like after ":split".
3839  * When "after" is 0 put it just after the current Tab page.
3840  * Otherwise put it just before tab page "after".
3841  * Return FAIL or OK.
3842  */
3843     int
3844 win_new_tabpage(int after)
3845 {
3846     tabpage_T	*tp = curtab;
3847     tabpage_T	*prev_tp = curtab;
3848     tabpage_T	*newtp;
3849     int		n;
3850 
3851     newtp = alloc_tabpage();
3852     if (newtp == NULL)
3853 	return FAIL;
3854 
3855     // Remember the current windows in this Tab page.
3856     if (leave_tabpage(curbuf, TRUE) == FAIL)
3857     {
3858 	vim_free(newtp);
3859 	return FAIL;
3860     }
3861     curtab = newtp;
3862 
3863     newtp->tp_localdir = (tp->tp_localdir == NULL)
3864 				    ? NULL : vim_strsave(tp->tp_localdir);
3865     // Create a new empty window.
3866     if (win_alloc_firstwin(tp->tp_curwin) == OK)
3867     {
3868 	// Make the new Tab page the new topframe.
3869 	if (after == 1)
3870 	{
3871 	    // New tab page becomes the first one.
3872 	    newtp->tp_next = first_tabpage;
3873 	    first_tabpage = newtp;
3874 	}
3875 	else
3876 	{
3877 	    if (after > 0)
3878 	    {
3879 		// Put new tab page before tab page "after".
3880 		n = 2;
3881 		for (tp = first_tabpage; tp->tp_next != NULL
3882 					       && n < after; tp = tp->tp_next)
3883 		    ++n;
3884 	    }
3885 	    newtp->tp_next = tp->tp_next;
3886 	    tp->tp_next = newtp;
3887 	}
3888 	newtp->tp_firstwin = newtp->tp_lastwin = newtp->tp_curwin = curwin;
3889 
3890 	win_init_size();
3891 	firstwin->w_winrow = tabline_height();
3892 	win_comp_scroll(curwin);
3893 
3894 	newtp->tp_topframe = topframe;
3895 	last_status(FALSE);
3896 
3897 	lastused_tabpage = prev_tp;
3898 
3899 #if defined(FEAT_GUI)
3900 	// When 'guioptions' includes 'L' or 'R' may have to remove or add
3901 	// scrollbars.  Have to update them anyway.
3902 	gui_may_update_scrollbars();
3903 #endif
3904 #ifdef FEAT_JOB_CHANNEL
3905 	entering_window(curwin);
3906 #endif
3907 
3908 	redraw_all_later(NOT_VALID);
3909 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
3910 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
3911 	apply_autocmds(EVENT_TABNEW, NULL, NULL, FALSE, curbuf);
3912 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3913 	return OK;
3914     }
3915 
3916     // Failed, get back the previous Tab page
3917     enter_tabpage(curtab, curbuf, TRUE, TRUE);
3918     return FAIL;
3919 }
3920 
3921 /*
3922  * Open a new tab page if ":tab cmd" was used.  It will edit the same buffer,
3923  * like with ":split".
3924  * Returns OK if a new tab page was created, FAIL otherwise.
3925  */
3926     static int
3927 may_open_tabpage(void)
3928 {
3929     int		n = (cmdmod.tab == 0) ? postponed_split_tab : cmdmod.tab;
3930 
3931     if (n != 0)
3932     {
3933 	cmdmod.tab = 0;	    // reset it to avoid doing it twice
3934 	postponed_split_tab = 0;
3935 	return win_new_tabpage(n);
3936     }
3937     return FAIL;
3938 }
3939 
3940 /*
3941  * Create up to "maxcount" tabpages with empty windows.
3942  * Returns the number of resulting tab pages.
3943  */
3944     int
3945 make_tabpages(int maxcount)
3946 {
3947     int		count = maxcount;
3948     int		todo;
3949 
3950     // Limit to 'tabpagemax' tabs.
3951     if (count > p_tpm)
3952 	count = p_tpm;
3953 
3954     /*
3955      * Don't execute autocommands while creating the tab pages.  Must do that
3956      * when putting the buffers in the windows.
3957      */
3958     block_autocmds();
3959 
3960     for (todo = count - 1; todo > 0; --todo)
3961 	if (win_new_tabpage(0) == FAIL)
3962 	    break;
3963 
3964     unblock_autocmds();
3965 
3966     // return actual number of tab pages
3967     return (count - todo);
3968 }
3969 
3970 /*
3971  * Return TRUE when "tpc" points to a valid tab page.
3972  */
3973     int
3974 valid_tabpage(tabpage_T *tpc)
3975 {
3976     tabpage_T	*tp;
3977 
3978     FOR_ALL_TABPAGES(tp)
3979 	if (tp == tpc)
3980 	    return TRUE;
3981     return FALSE;
3982 }
3983 
3984 /*
3985  * Return TRUE when "tpc" points to a valid tab page and at least one window is
3986  * valid.
3987  */
3988     int
3989 valid_tabpage_win(tabpage_T *tpc)
3990 {
3991     tabpage_T	*tp;
3992     win_T	*wp;
3993 
3994     FOR_ALL_TABPAGES(tp)
3995     {
3996 	if (tp == tpc)
3997 	{
3998 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
3999 	    {
4000 		if (win_valid_any_tab(wp))
4001 		    return TRUE;
4002 	    }
4003 	    return FALSE;
4004 	}
4005     }
4006     // shouldn't happen
4007     return FALSE;
4008 }
4009 
4010 /*
4011  * Close tabpage "tab", assuming it has no windows in it.
4012  * There must be another tabpage or this will crash.
4013  */
4014     void
4015 close_tabpage(tabpage_T *tab)
4016 {
4017     tabpage_T	*ptp;
4018 
4019     if (tab == first_tabpage)
4020     {
4021 	first_tabpage = tab->tp_next;
4022 	ptp = first_tabpage;
4023     }
4024     else
4025     {
4026 	for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tab;
4027 							    ptp = ptp->tp_next)
4028 	    ;
4029 	assert(ptp != NULL);
4030 	ptp->tp_next = tab->tp_next;
4031     }
4032 
4033     goto_tabpage_tp(ptp, FALSE, FALSE);
4034     free_tabpage(tab);
4035 }
4036 
4037 /*
4038  * Find tab page "n" (first one is 1).  Returns NULL when not found.
4039  */
4040     tabpage_T *
4041 find_tabpage(int n)
4042 {
4043     tabpage_T	*tp;
4044     int		i = 1;
4045 
4046     if (n == 0)
4047 	return curtab;
4048 
4049     for (tp = first_tabpage; tp != NULL && i != n; tp = tp->tp_next)
4050 	++i;
4051     return tp;
4052 }
4053 
4054 /*
4055  * Get index of tab page "tp".  First one has index 1.
4056  * When not found returns number of tab pages plus one.
4057  */
4058     int
4059 tabpage_index(tabpage_T *ftp)
4060 {
4061     int		i = 1;
4062     tabpage_T	*tp;
4063 
4064     for (tp = first_tabpage; tp != NULL && tp != ftp; tp = tp->tp_next)
4065 	++i;
4066     return i;
4067 }
4068 
4069 /*
4070  * Prepare for leaving the current tab page.
4071  * When autocommands change "curtab" we don't leave the tab page and return
4072  * FAIL.
4073  * Careful: When OK is returned need to get a new tab page very very soon!
4074  */
4075     static int
4076 leave_tabpage(
4077     buf_T	*new_curbuf UNUSED,    // what is going to be the new curbuf,
4078 				       // NULL if unknown
4079     int		trigger_leave_autocmds UNUSED)
4080 {
4081     tabpage_T	*tp = curtab;
4082 
4083 #ifdef FEAT_JOB_CHANNEL
4084     leaving_window(curwin);
4085 #endif
4086     reset_VIsual_and_resel();	// stop Visual mode
4087     if (trigger_leave_autocmds)
4088     {
4089 	if (new_curbuf != curbuf)
4090 	{
4091 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4092 	    if (curtab != tp)
4093 		return FAIL;
4094 	}
4095 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4096 	if (curtab != tp)
4097 	    return FAIL;
4098 	apply_autocmds(EVENT_TABLEAVE, NULL, NULL, FALSE, curbuf);
4099 	if (curtab != tp)
4100 	    return FAIL;
4101     }
4102 #if defined(FEAT_GUI)
4103     // Remove the scrollbars.  They may be added back later.
4104     if (gui.in_use)
4105 	gui_remove_scrollbars();
4106 #endif
4107     tp->tp_curwin = curwin;
4108     tp->tp_prevwin = prevwin;
4109     tp->tp_firstwin = firstwin;
4110     tp->tp_lastwin = lastwin;
4111     tp->tp_old_Rows = Rows;
4112     tp->tp_old_Columns = Columns;
4113     firstwin = NULL;
4114     lastwin = NULL;
4115     return OK;
4116 }
4117 
4118 /*
4119  * Start using tab page "tp".
4120  * Only to be used after leave_tabpage() or freeing the current tab page.
4121  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4122  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4123  */
4124     static void
4125 enter_tabpage(
4126     tabpage_T	*tp,
4127     buf_T	*old_curbuf UNUSED,
4128     int		trigger_enter_autocmds,
4129     int		trigger_leave_autocmds)
4130 {
4131     int		row;
4132     int		old_off = tp->tp_firstwin->w_winrow;
4133     win_T	*next_prevwin = tp->tp_prevwin;
4134     tabpage_T	*last_tab = curtab;
4135 
4136     curtab = tp;
4137     firstwin = tp->tp_firstwin;
4138     lastwin = tp->tp_lastwin;
4139     topframe = tp->tp_topframe;
4140 
4141     // We would like doing the TabEnter event first, but we don't have a
4142     // valid current window yet, which may break some commands.
4143     // This triggers autocommands, thus may make "tp" invalid.
4144     win_enter_ext(tp->tp_curwin, FALSE, TRUE, FALSE,
4145 			      trigger_enter_autocmds, trigger_leave_autocmds);
4146     prevwin = next_prevwin;
4147 
4148     last_status(FALSE);		// status line may appear or disappear
4149     row = win_comp_pos();	// recompute w_winrow for all windows
4150 #ifdef FEAT_DIFF
4151     diff_need_scrollbind = TRUE;
4152 #endif
4153 
4154     // The tabpage line may have appeared or disappeared, may need to resize
4155     // the frames for that.  When the Vim window was resized need to update
4156     // frame sizes too.  Use the stored value of p_ch, so that it can be
4157     // different for each tab page.
4158     if (p_ch != curtab->tp_ch_used)
4159 	clear_cmdline = TRUE;
4160     p_ch = curtab->tp_ch_used;
4161 
4162     // When cmdheight is changed in a tab page with '<C-w>-', cmdline_row is
4163     // changed but p_ch and tp_ch_used are not changed. Thus we also need to
4164     // check cmdline_row.
4165     if ((row < cmdline_row) && (cmdline_row <= Rows - p_ch))
4166 	clear_cmdline = TRUE;
4167 
4168     if (curtab->tp_old_Rows != Rows || (old_off != firstwin->w_winrow
4169 #ifdef FEAT_GUI_TABLINE
4170 			    && !gui_use_tabline()
4171 #endif
4172 		))
4173 	shell_new_rows();
4174     if (curtab->tp_old_Columns != Columns && starting == 0)
4175 	shell_new_columns();	// update window widths
4176 
4177     lastused_tabpage = last_tab;
4178 
4179 #if defined(FEAT_GUI)
4180     // When 'guioptions' includes 'L' or 'R' may have to remove or add
4181     // scrollbars.  Have to update them anyway.
4182     gui_may_update_scrollbars();
4183 #endif
4184 
4185     // Apply autocommands after updating the display, when 'rows' and
4186     // 'columns' have been set correctly.
4187     if (trigger_enter_autocmds)
4188     {
4189 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
4190 	if (old_curbuf != curbuf)
4191 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4192     }
4193 
4194     redraw_all_later(NOT_VALID);
4195 }
4196 
4197 /*
4198  * Go to tab page "n".  For ":tab N" and "Ngt".
4199  * When "n" is 9999 go to the last tab page.
4200  */
4201     void
4202 goto_tabpage(int n)
4203 {
4204     tabpage_T	*tp = NULL;  // shut up compiler
4205     tabpage_T	*ttp;
4206     int		i;
4207 
4208     if (text_locked())
4209     {
4210 	// Not allowed when editing the command line.
4211 	text_locked_msg();
4212 	return;
4213     }
4214 
4215     // If there is only one it can't work.
4216     if (first_tabpage->tp_next == NULL)
4217     {
4218 	if (n > 1)
4219 	    beep_flush();
4220 	return;
4221     }
4222 
4223     if (n == 0)
4224     {
4225 	// No count, go to next tab page, wrap around end.
4226 	if (curtab->tp_next == NULL)
4227 	    tp = first_tabpage;
4228 	else
4229 	    tp = curtab->tp_next;
4230     }
4231     else if (n < 0)
4232     {
4233 	// "gT": go to previous tab page, wrap around end.  "N gT" repeats
4234 	// this N times.
4235 	ttp = curtab;
4236 	for (i = n; i < 0; ++i)
4237 	{
4238 	    for (tp = first_tabpage; tp->tp_next != ttp && tp->tp_next != NULL;
4239 		    tp = tp->tp_next)
4240 		;
4241 	    ttp = tp;
4242 	}
4243     }
4244     else if (n == 9999)
4245     {
4246 	// Go to last tab page.
4247 	for (tp = first_tabpage; tp->tp_next != NULL; tp = tp->tp_next)
4248 	    ;
4249     }
4250     else
4251     {
4252 	// Go to tab page "n".
4253 	tp = find_tabpage(n);
4254 	if (tp == NULL)
4255 	{
4256 	    beep_flush();
4257 	    return;
4258 	}
4259     }
4260 
4261     goto_tabpage_tp(tp, TRUE, TRUE);
4262 
4263 #ifdef FEAT_GUI_TABLINE
4264     if (gui_use_tabline())
4265 	gui_mch_set_curtab(tabpage_index(curtab));
4266 #endif
4267 }
4268 
4269 /*
4270  * Go to tabpage "tp".
4271  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4272  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4273  * Note: doesn't update the GUI tab.
4274  */
4275     void
4276 goto_tabpage_tp(
4277     tabpage_T	*tp,
4278     int		trigger_enter_autocmds,
4279     int		trigger_leave_autocmds)
4280 {
4281     // Don't repeat a message in another tab page.
4282     set_keep_msg(NULL, 0);
4283 
4284     if (tp != curtab && leave_tabpage(tp->tp_curwin->w_buffer,
4285 					trigger_leave_autocmds) == OK)
4286     {
4287 	if (valid_tabpage(tp))
4288 	    enter_tabpage(tp, curbuf, trigger_enter_autocmds,
4289 		    trigger_leave_autocmds);
4290 	else
4291 	    enter_tabpage(curtab, curbuf, trigger_enter_autocmds,
4292 		    trigger_leave_autocmds);
4293     }
4294 }
4295 
4296 /*
4297  * Go to the last accessed tab page, if there is one.
4298  * Return OK or FAIL
4299  */
4300     int
4301 goto_tabpage_lastused(void)
4302 {
4303     if (valid_tabpage(lastused_tabpage))
4304     {
4305 	goto_tabpage_tp(lastused_tabpage, TRUE, TRUE);
4306 	return OK;
4307     }
4308     return FAIL;
4309 }
4310 
4311 /*
4312  * Enter window "wp" in tab page "tp".
4313  * Also updates the GUI tab.
4314  */
4315     void
4316 goto_tabpage_win(tabpage_T *tp, win_T *wp)
4317 {
4318     goto_tabpage_tp(tp, TRUE, TRUE);
4319     if (curtab == tp && win_valid(wp))
4320     {
4321 	win_enter(wp, TRUE);
4322 # ifdef FEAT_GUI_TABLINE
4323 	if (gui_use_tabline())
4324 	    gui_mch_set_curtab(tabpage_index(curtab));
4325 # endif
4326     }
4327 }
4328 
4329 /*
4330  * Move the current tab page to after tab page "nr".
4331  */
4332     void
4333 tabpage_move(int nr)
4334 {
4335     int		n = 1;
4336     tabpage_T	*tp, *tp_dst;
4337 
4338     if (first_tabpage->tp_next == NULL)
4339 	return;
4340 
4341     for (tp = first_tabpage; tp->tp_next != NULL && n < nr; tp = tp->tp_next)
4342 	++n;
4343 
4344     if (tp == curtab || (nr > 0 && tp->tp_next != NULL
4345 						    && tp->tp_next == curtab))
4346 	return;
4347 
4348     tp_dst = tp;
4349 
4350     // Remove the current tab page from the list of tab pages.
4351     if (curtab == first_tabpage)
4352 	first_tabpage = curtab->tp_next;
4353     else
4354     {
4355 	FOR_ALL_TABPAGES(tp)
4356 	    if (tp->tp_next == curtab)
4357 		break;
4358 	if (tp == NULL)	// "cannot happen"
4359 	    return;
4360 	tp->tp_next = curtab->tp_next;
4361     }
4362 
4363     // Re-insert it at the specified position.
4364     if (nr <= 0)
4365     {
4366 	curtab->tp_next = first_tabpage;
4367 	first_tabpage = curtab;
4368     }
4369     else
4370     {
4371 	curtab->tp_next = tp_dst->tp_next;
4372 	tp_dst->tp_next = curtab;
4373     }
4374 
4375     // Need to redraw the tabline.  Tab page contents doesn't change.
4376     redraw_tabline = TRUE;
4377 }
4378 
4379 
4380 /*
4381  * Go to another window.
4382  * When jumping to another buffer, stop Visual mode.  Do this before
4383  * changing windows so we can yank the selection into the '*' register.
4384  * When jumping to another window on the same buffer, adjust its cursor
4385  * position to keep the same Visual area.
4386  */
4387     void
4388 win_goto(win_T *wp)
4389 {
4390 #ifdef FEAT_CONCEAL
4391     win_T	*owp = curwin;
4392 #endif
4393 
4394 #ifdef FEAT_PROP_POPUP
4395     if (ERROR_IF_ANY_POPUP_WINDOW)
4396 	return;
4397     if (popup_is_popup(wp))
4398     {
4399 	emsg(_("E366: Not allowed to enter a popup window"));
4400 	return;
4401     }
4402 #endif
4403     if (text_and_win_locked())
4404     {
4405 	beep_flush();
4406 	text_locked_msg();
4407 	return;
4408     }
4409     if (curbuf_locked())
4410 	return;
4411 
4412     if (wp->w_buffer != curbuf)
4413 	reset_VIsual_and_resel();
4414     else if (VIsual_active)
4415 	wp->w_cursor = curwin->w_cursor;
4416 
4417 #ifdef FEAT_GUI
4418     need_mouse_correct = TRUE;
4419 #endif
4420     win_enter(wp, TRUE);
4421 
4422 #ifdef FEAT_CONCEAL
4423     // Conceal cursor line in previous window, unconceal in current window.
4424     if (win_valid(owp) && owp->w_p_cole > 0 && !msg_scrolled)
4425 	redrawWinline(owp, owp->w_cursor.lnum);
4426     if (curwin->w_p_cole > 0 && !msg_scrolled)
4427 	need_cursor_line_redraw = TRUE;
4428 #endif
4429 }
4430 
4431 #if defined(FEAT_PERL) || defined(PROTO)
4432 /*
4433  * Find window number "winnr" (counting top to bottom).
4434  */
4435     win_T *
4436 win_find_nr(int winnr)
4437 {
4438     win_T	*wp;
4439 
4440     FOR_ALL_WINDOWS(wp)
4441 	if (--winnr == 0)
4442 	    break;
4443     return wp;
4444 }
4445 #endif
4446 
4447 #if ((defined(FEAT_PYTHON) || defined(FEAT_PYTHON3))) || defined(PROTO)
4448 /*
4449  * Find the tabpage for window "win".
4450  */
4451     tabpage_T *
4452 win_find_tabpage(win_T *win)
4453 {
4454     win_T	*wp;
4455     tabpage_T	*tp;
4456 
4457     FOR_ALL_TAB_WINDOWS(tp, wp)
4458 	    if (wp == win)
4459 		return tp;
4460     return NULL;
4461 }
4462 #endif
4463 
4464 /*
4465  * Get the above or below neighbor window of the specified window.
4466  *   up - TRUE for the above neighbor
4467  *   count - nth neighbor window
4468  * Returns the specified window if the neighbor is not found.
4469  */
4470     win_T *
4471 win_vert_neighbor(tabpage_T *tp, win_T *wp, int up, long count)
4472 {
4473     frame_T	*fr;
4474     frame_T	*nfr;
4475     frame_T	*foundfr;
4476 
4477 #ifdef FEAT_PROP_POPUP
4478     if (popup_is_popup(wp))
4479 	// popups don't have neighbors.
4480 	return NULL;
4481 #endif
4482     foundfr = wp->w_frame;
4483     while (count--)
4484     {
4485 	/*
4486 	 * First go upwards in the tree of frames until we find a upwards or
4487 	 * downwards neighbor.
4488 	 */
4489 	fr = foundfr;
4490 	for (;;)
4491 	{
4492 	    if (fr == tp->tp_topframe)
4493 		goto end;
4494 	    if (up)
4495 		nfr = fr->fr_prev;
4496 	    else
4497 		nfr = fr->fr_next;
4498 	    if (fr->fr_parent->fr_layout == FR_COL && nfr != NULL)
4499 		break;
4500 	    fr = fr->fr_parent;
4501 	}
4502 
4503 	/*
4504 	 * Now go downwards to find the bottom or top frame in it.
4505 	 */
4506 	for (;;)
4507 	{
4508 	    if (nfr->fr_layout == FR_LEAF)
4509 	    {
4510 		foundfr = nfr;
4511 		break;
4512 	    }
4513 	    fr = nfr->fr_child;
4514 	    if (nfr->fr_layout == FR_ROW)
4515 	    {
4516 		// Find the frame at the cursor row.
4517 		while (fr->fr_next != NULL
4518 			&& frame2win(fr)->w_wincol + fr->fr_width
4519 					 <= wp->w_wincol + wp->w_wcol)
4520 		    fr = fr->fr_next;
4521 	    }
4522 	    if (nfr->fr_layout == FR_COL && up)
4523 		while (fr->fr_next != NULL)
4524 		    fr = fr->fr_next;
4525 	    nfr = fr;
4526 	}
4527     }
4528 end:
4529     return foundfr != NULL ? foundfr->fr_win : NULL;
4530 }
4531 
4532 /*
4533  * Move to window above or below "count" times.
4534  */
4535     static void
4536 win_goto_ver(
4537     int		up,		// TRUE to go to win above
4538     long	count)
4539 {
4540     win_T	*win;
4541 
4542 #ifdef FEAT_PROP_POPUP
4543     if (ERROR_IF_TERM_POPUP_WINDOW)
4544 	return;
4545 #endif
4546     win = win_vert_neighbor(curtab, curwin, up, count);
4547     if (win != NULL)
4548 	win_goto(win);
4549 }
4550 
4551 /*
4552  * Get the left or right neighbor window of the specified window.
4553  *   left - TRUE for the left neighbor
4554  *   count - nth neighbor window
4555  * Returns the specified window if the neighbor is not found.
4556  */
4557     win_T *
4558 win_horz_neighbor(tabpage_T *tp, win_T *wp, int left, long count)
4559 {
4560     frame_T	*fr;
4561     frame_T	*nfr;
4562     frame_T	*foundfr;
4563 
4564 #ifdef FEAT_PROP_POPUP
4565     if (popup_is_popup(wp))
4566 	// popups don't have neighbors.
4567 	return NULL;
4568 #endif
4569     foundfr = wp->w_frame;
4570     while (count--)
4571     {
4572 	/*
4573 	 * First go upwards in the tree of frames until we find a left or
4574 	 * right neighbor.
4575 	 */
4576 	fr = foundfr;
4577 	for (;;)
4578 	{
4579 	    if (fr == tp->tp_topframe)
4580 		goto end;
4581 	    if (left)
4582 		nfr = fr->fr_prev;
4583 	    else
4584 		nfr = fr->fr_next;
4585 	    if (fr->fr_parent->fr_layout == FR_ROW && nfr != NULL)
4586 		break;
4587 	    fr = fr->fr_parent;
4588 	}
4589 
4590 	/*
4591 	 * Now go downwards to find the leftmost or rightmost frame in it.
4592 	 */
4593 	for (;;)
4594 	{
4595 	    if (nfr->fr_layout == FR_LEAF)
4596 	    {
4597 		foundfr = nfr;
4598 		break;
4599 	    }
4600 	    fr = nfr->fr_child;
4601 	    if (nfr->fr_layout == FR_COL)
4602 	    {
4603 		// Find the frame at the cursor row.
4604 		while (fr->fr_next != NULL
4605 			&& frame2win(fr)->w_winrow + fr->fr_height
4606 					 <= wp->w_winrow + wp->w_wrow)
4607 		    fr = fr->fr_next;
4608 	    }
4609 	    if (nfr->fr_layout == FR_ROW && left)
4610 		while (fr->fr_next != NULL)
4611 		    fr = fr->fr_next;
4612 	    nfr = fr;
4613 	}
4614     }
4615 end:
4616     return foundfr != NULL ? foundfr->fr_win : NULL;
4617 }
4618 
4619 /*
4620  * Move to left or right window.
4621  */
4622     static void
4623 win_goto_hor(
4624     int		left,		// TRUE to go to left win
4625     long	count)
4626 {
4627     win_T	*win;
4628 
4629 #ifdef FEAT_PROP_POPUP
4630     if (ERROR_IF_TERM_POPUP_WINDOW)
4631 	return;
4632 #endif
4633     win = win_horz_neighbor(curtab, curwin, left, count);
4634     if (win != NULL)
4635 	win_goto(win);
4636 }
4637 
4638 /*
4639  * Make window "wp" the current window.
4640  */
4641     void
4642 win_enter(win_T *wp, int undo_sync)
4643 {
4644     win_enter_ext(wp, undo_sync, FALSE, FALSE, TRUE, TRUE);
4645 }
4646 
4647 /*
4648  * Make window wp the current window.
4649  * Can be called with "curwin_invalid" TRUE, which means that curwin has just
4650  * been closed and isn't valid.
4651  */
4652     static void
4653 win_enter_ext(
4654     win_T	*wp,
4655     int		undo_sync,
4656     int		curwin_invalid,
4657     int		trigger_new_autocmds,
4658     int		trigger_enter_autocmds,
4659     int		trigger_leave_autocmds)
4660 {
4661     int		other_buffer = FALSE;
4662 
4663     if (wp == curwin && !curwin_invalid)	// nothing to do
4664 	return;
4665 
4666 #ifdef FEAT_JOB_CHANNEL
4667     if (!curwin_invalid)
4668 	leaving_window(curwin);
4669 #endif
4670 
4671     if (!curwin_invalid && trigger_leave_autocmds)
4672     {
4673 	/*
4674 	 * Be careful: If autocommands delete the window, return now.
4675 	 */
4676 	if (wp->w_buffer != curbuf)
4677 	{
4678 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4679 	    other_buffer = TRUE;
4680 	    if (!win_valid(wp))
4681 		return;
4682 	}
4683 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4684 	if (!win_valid(wp))
4685 	    return;
4686 #ifdef FEAT_EVAL
4687 	// autocmds may abort script processing
4688 	if (aborting())
4689 	    return;
4690 #endif
4691     }
4692 
4693     // sync undo before leaving the current buffer
4694     if (undo_sync && curbuf != wp->w_buffer)
4695 	u_sync(FALSE);
4696 
4697     // Might need to scroll the old window before switching, e.g., when the
4698     // cursor was moved.
4699     update_topline();
4700 
4701     // may have to copy the buffer options when 'cpo' contains 'S'
4702     if (wp->w_buffer != curbuf)
4703 	buf_copy_options(wp->w_buffer, BCO_ENTER | BCO_NOHELP);
4704     if (!curwin_invalid)
4705     {
4706 	prevwin = curwin;	// remember for CTRL-W p
4707 	curwin->w_redr_status = TRUE;
4708     }
4709     curwin = wp;
4710     curbuf = wp->w_buffer;
4711     check_cursor();
4712     if (!virtual_active())
4713 	curwin->w_cursor.coladd = 0;
4714     changed_line_abv_curs();	// assume cursor position needs updating
4715 
4716     if (curwin->w_localdir != NULL || curtab->tp_localdir != NULL)
4717     {
4718 	char_u	*dirname;
4719 
4720 	// Window or tab has a local directory: Save current directory as
4721 	// global directory (unless that was done already) and change to the
4722 	// local directory.
4723 	if (globaldir == NULL)
4724 	{
4725 	    char_u	cwd[MAXPATHL];
4726 
4727 	    if (mch_dirname(cwd, MAXPATHL) == OK)
4728 		globaldir = vim_strsave(cwd);
4729 	}
4730 	if (curwin->w_localdir != NULL)
4731 	    dirname = curwin->w_localdir;
4732 	else
4733 	    dirname = curtab->tp_localdir;
4734 
4735 	if (mch_chdir((char *)dirname) == 0)
4736 	    shorten_fnames(TRUE);
4737     }
4738     else if (globaldir != NULL)
4739     {
4740 	// Window doesn't have a local directory and we are not in the global
4741 	// directory: Change to the global directory.
4742 	vim_ignored = mch_chdir((char *)globaldir);
4743 	VIM_CLEAR(globaldir);
4744 	shorten_fnames(TRUE);
4745     }
4746 
4747 #ifdef FEAT_JOB_CHANNEL
4748     entering_window(curwin);
4749 #endif
4750     // Careful: autocommands may close the window and make "wp" invalid
4751     if (trigger_new_autocmds)
4752 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
4753     if (trigger_enter_autocmds)
4754     {
4755 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
4756 	if (other_buffer)
4757 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4758     }
4759 
4760 #ifdef FEAT_TITLE
4761     maketitle();
4762 #endif
4763     curwin->w_redr_status = TRUE;
4764 #ifdef FEAT_TERMINAL
4765     if (bt_terminal(curwin->w_buffer))
4766 	// terminal is likely in another mode
4767 	redraw_mode = TRUE;
4768 #endif
4769     redraw_tabline = TRUE;
4770     if (restart_edit)
4771 	redraw_later(VALID);	// causes status line redraw
4772 
4773     // set window height to desired minimal value
4774     if (curwin->w_height < p_wh && !curwin->w_p_wfh
4775 #ifdef FEAT_PROP_POPUP
4776 	    && !popup_is_popup(curwin)
4777 #endif
4778 	    )
4779 	win_setheight((int)p_wh);
4780     else if (curwin->w_height == 0)
4781 	win_setheight(1);
4782 
4783     // set window width to desired minimal value
4784     if (curwin->w_width < p_wiw && !curwin->w_p_wfw)
4785 	win_setwidth((int)p_wiw);
4786 
4787     setmouse();			// in case jumped to/from help buffer
4788 
4789     // Change directories when the 'acd' option is set.
4790     DO_AUTOCHDIR;
4791 }
4792 
4793 
4794 /*
4795  * Jump to the first open window that contains buffer "buf", if one exists.
4796  * Returns a pointer to the window found, otherwise NULL.
4797  */
4798     win_T *
4799 buf_jump_open_win(buf_T *buf)
4800 {
4801     win_T	*wp = NULL;
4802 
4803     if (curwin->w_buffer == buf)
4804 	wp = curwin;
4805     else
4806 	FOR_ALL_WINDOWS(wp)
4807 	    if (wp->w_buffer == buf)
4808 		break;
4809     if (wp != NULL)
4810 	win_enter(wp, FALSE);
4811     return wp;
4812 }
4813 
4814 /*
4815  * Jump to the first open window in any tab page that contains buffer "buf",
4816  * if one exists.
4817  * Returns a pointer to the window found, otherwise NULL.
4818  */
4819     win_T *
4820 buf_jump_open_tab(buf_T *buf)
4821 {
4822     win_T	*wp = buf_jump_open_win(buf);
4823     tabpage_T	*tp;
4824 
4825     if (wp != NULL)
4826 	return wp;
4827 
4828     FOR_ALL_TABPAGES(tp)
4829 	if (tp != curtab)
4830 	{
4831 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
4832 		if (wp->w_buffer == buf)
4833 		    break;
4834 	    if (wp != NULL)
4835 	    {
4836 		goto_tabpage_win(tp, wp);
4837 		if (curwin != wp)
4838 		    wp = NULL;	// something went wrong
4839 		break;
4840 	    }
4841 	}
4842     return wp;
4843 }
4844 
4845 static int last_win_id = LOWEST_WIN_ID - 1;
4846 
4847 /*
4848  * Allocate a window structure and link it in the window list when "hidden" is
4849  * FALSE.
4850  */
4851     static win_T *
4852 win_alloc(win_T *after UNUSED, int hidden UNUSED)
4853 {
4854     win_T	*new_wp;
4855 
4856     /*
4857      * allocate window structure and linesizes arrays
4858      */
4859     new_wp = ALLOC_CLEAR_ONE(win_T);
4860     if (new_wp == NULL)
4861 	return NULL;
4862 
4863     if (win_alloc_lines(new_wp) == FAIL)
4864     {
4865 	vim_free(new_wp);
4866 	return NULL;
4867     }
4868 
4869     new_wp->w_id = ++last_win_id;
4870 
4871 #ifdef FEAT_EVAL
4872     // init w: variables
4873     new_wp->w_vars = dict_alloc();
4874     if (new_wp->w_vars == NULL)
4875     {
4876 	win_free_lsize(new_wp);
4877 	vim_free(new_wp);
4878 	return NULL;
4879     }
4880     init_var_dict(new_wp->w_vars, &new_wp->w_winvar, VAR_SCOPE);
4881 #endif
4882 
4883     // Don't execute autocommands while the window is not properly
4884     // initialized yet.  gui_create_scrollbar() may trigger a FocusGained
4885     // event.
4886     block_autocmds();
4887 
4888     /*
4889      * link the window in the window list
4890      */
4891     if (!hidden)
4892 	win_append(after, new_wp);
4893     new_wp->w_wincol = 0;
4894     new_wp->w_width = Columns;
4895 
4896     // position the display and the cursor at the top of the file.
4897     new_wp->w_topline = 1;
4898 #ifdef FEAT_DIFF
4899     new_wp->w_topfill = 0;
4900 #endif
4901     new_wp->w_botline = 2;
4902     new_wp->w_cursor.lnum = 1;
4903     new_wp->w_scbind_pos = 1;
4904 
4905     // use global option value for global-local options
4906     new_wp->w_p_so = -1;
4907     new_wp->w_p_siso = -1;
4908 
4909     // We won't calculate w_fraction until resizing the window
4910     new_wp->w_fraction = 0;
4911     new_wp->w_prev_fraction_row = -1;
4912 
4913 #ifdef FEAT_GUI
4914     if (gui.in_use)
4915     {
4916 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_LEFT],
4917 		SBAR_LEFT, new_wp);
4918 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_RIGHT],
4919 		SBAR_RIGHT, new_wp);
4920     }
4921 #endif
4922 #ifdef FEAT_FOLDING
4923     foldInitWin(new_wp);
4924 #endif
4925     unblock_autocmds();
4926 #ifdef FEAT_SEARCH_EXTRA
4927     new_wp->w_match_head = NULL;
4928     new_wp->w_next_match_id = 4;
4929 #endif
4930     return new_wp;
4931 }
4932 
4933 /*
4934  * Remove window 'wp' from the window list and free the structure.
4935  */
4936     static void
4937 win_free(
4938     win_T	*wp,
4939     tabpage_T	*tp)		// tab page "win" is in, NULL for current
4940 {
4941     int		i;
4942     buf_T	*buf;
4943     wininfo_T	*wip;
4944 
4945 #ifdef FEAT_FOLDING
4946     clearFolding(wp);
4947 #endif
4948 
4949     // reduce the reference count to the argument list.
4950     alist_unlink(wp->w_alist);
4951 
4952     // Don't execute autocommands while the window is halfway being deleted.
4953     // gui_mch_destroy_scrollbar() may trigger a FocusGained event.
4954     block_autocmds();
4955 
4956 #ifdef FEAT_LUA
4957     lua_window_free(wp);
4958 #endif
4959 
4960 #ifdef FEAT_MZSCHEME
4961     mzscheme_window_free(wp);
4962 #endif
4963 
4964 #ifdef FEAT_PERL
4965     perl_win_free(wp);
4966 #endif
4967 
4968 #ifdef FEAT_PYTHON
4969     python_window_free(wp);
4970 #endif
4971 
4972 #ifdef FEAT_PYTHON3
4973     python3_window_free(wp);
4974 #endif
4975 
4976 #ifdef FEAT_TCL
4977     tcl_window_free(wp);
4978 #endif
4979 
4980 #ifdef FEAT_RUBY
4981     ruby_window_free(wp);
4982 #endif
4983 
4984     clear_winopt(&wp->w_onebuf_opt);
4985     clear_winopt(&wp->w_allbuf_opt);
4986 
4987 #ifdef FEAT_EVAL
4988     vars_clear(&wp->w_vars->dv_hashtab);	// free all w: variables
4989     hash_init(&wp->w_vars->dv_hashtab);
4990     unref_var_dict(wp->w_vars);
4991 #endif
4992 
4993     {
4994 	tabpage_T	*ttp;
4995 
4996 	if (prevwin == wp)
4997 	    prevwin = NULL;
4998 	FOR_ALL_TABPAGES(ttp)
4999 	    if (ttp->tp_prevwin == wp)
5000 		ttp->tp_prevwin = NULL;
5001     }
5002     win_free_lsize(wp);
5003 
5004     for (i = 0; i < wp->w_tagstacklen; ++i)
5005     {
5006 	vim_free(wp->w_tagstack[i].tagname);
5007 	vim_free(wp->w_tagstack[i].user_data);
5008     }
5009     vim_free(wp->w_localdir);
5010     vim_free(wp->w_prevdir);
5011 
5012     // Remove the window from the b_wininfo lists, it may happen that the
5013     // freed memory is re-used for another window.
5014     FOR_ALL_BUFFERS(buf)
5015 	FOR_ALL_BUF_WININFO(buf, wip)
5016 	    if (wip->wi_win == wp)
5017 		wip->wi_win = NULL;
5018 
5019 #ifdef FEAT_SEARCH_EXTRA
5020     clear_matches(wp);
5021 #endif
5022 
5023 #ifdef FEAT_JUMPLIST
5024     free_jumplist(wp);
5025 #endif
5026 
5027 #ifdef FEAT_QUICKFIX
5028     qf_free_all(wp);
5029 #endif
5030 
5031 #ifdef FEAT_GUI
5032     if (gui.in_use)
5033     {
5034 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_LEFT]);
5035 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_RIGHT]);
5036     }
5037 #endif // FEAT_GUI
5038 
5039 #ifdef FEAT_MENU
5040     remove_winbar(wp);
5041 #endif
5042 #ifdef FEAT_PROP_POPUP
5043     free_callback(&wp->w_close_cb);
5044     free_callback(&wp->w_filter_cb);
5045     for (i = 0; i < 4; ++i)
5046 	VIM_CLEAR(wp->w_border_highlight[i]);
5047     vim_free(wp->w_scrollbar_highlight);
5048     vim_free(wp->w_thumb_highlight);
5049     vim_free(wp->w_popup_title);
5050     list_unref(wp->w_popup_mask);
5051     vim_free(wp->w_popup_mask_cells);
5052 #endif
5053 
5054 #ifdef FEAT_SYN_HL
5055     vim_free(wp->w_p_cc_cols);
5056 #endif
5057 
5058     if (win_valid_any_tab(wp))
5059 	win_remove(wp, tp);
5060     if (autocmd_busy)
5061     {
5062 	wp->w_next = au_pending_free_win;
5063 	au_pending_free_win = wp;
5064     }
5065     else
5066 	vim_free(wp);
5067 
5068     unblock_autocmds();
5069 }
5070 
5071 /*
5072  * Return TRUE if "wp" is not in the list of windows: the autocmd window or a
5073  * popup window.
5074  */
5075     static int
5076 win_unlisted(win_T *wp)
5077 {
5078     return wp == aucmd_win || WIN_IS_POPUP(wp);
5079 }
5080 
5081 #if defined(FEAT_PROP_POPUP) || defined(PROTO)
5082 /*
5083  * Free a popup window.  This does not take the window out of the window list
5084  * and assumes there is only one toplevel frame, no split.
5085  */
5086     void
5087 win_free_popup(win_T *win)
5088 {
5089     if (bt_popup(win->w_buffer))
5090 	win_close_buffer(win, DOBUF_WIPE_REUSE, FALSE);
5091     else
5092 	close_buffer(win, win->w_buffer, 0, FALSE, FALSE);
5093 # if defined(FEAT_TIMERS)
5094     if (win->w_popup_timer != NULL)
5095 	stop_timer(win->w_popup_timer);
5096 # endif
5097     vim_free(win->w_frame);
5098     win_free(win, NULL);
5099 }
5100 #endif
5101 
5102 /*
5103  * Append window "wp" in the window list after window "after".
5104  */
5105     static void
5106 win_append(win_T *after, win_T *wp)
5107 {
5108     win_T	*before;
5109 
5110     if (after == NULL)	    // after NULL is in front of the first
5111 	before = firstwin;
5112     else
5113 	before = after->w_next;
5114 
5115     wp->w_next = before;
5116     wp->w_prev = after;
5117     if (after == NULL)
5118 	firstwin = wp;
5119     else
5120 	after->w_next = wp;
5121     if (before == NULL)
5122 	lastwin = wp;
5123     else
5124 	before->w_prev = wp;
5125 }
5126 
5127 /*
5128  * Remove a window from the window list.
5129  */
5130     void
5131 win_remove(
5132     win_T	*wp,
5133     tabpage_T	*tp)		// tab page "win" is in, NULL for current
5134 {
5135     if (wp->w_prev != NULL)
5136 	wp->w_prev->w_next = wp->w_next;
5137     else if (tp == NULL)
5138 	firstwin = curtab->tp_firstwin = wp->w_next;
5139     else
5140 	tp->tp_firstwin = wp->w_next;
5141 
5142     if (wp->w_next != NULL)
5143 	wp->w_next->w_prev = wp->w_prev;
5144     else if (tp == NULL)
5145 	lastwin = curtab->tp_lastwin = wp->w_prev;
5146     else
5147 	tp->tp_lastwin = wp->w_prev;
5148 }
5149 
5150 /*
5151  * Append frame "frp" in a frame list after frame "after".
5152  */
5153     static void
5154 frame_append(frame_T *after, frame_T *frp)
5155 {
5156     frp->fr_next = after->fr_next;
5157     after->fr_next = frp;
5158     if (frp->fr_next != NULL)
5159 	frp->fr_next->fr_prev = frp;
5160     frp->fr_prev = after;
5161 }
5162 
5163 /*
5164  * Insert frame "frp" in a frame list before frame "before".
5165  */
5166     static void
5167 frame_insert(frame_T *before, frame_T *frp)
5168 {
5169     frp->fr_next = before;
5170     frp->fr_prev = before->fr_prev;
5171     before->fr_prev = frp;
5172     if (frp->fr_prev != NULL)
5173 	frp->fr_prev->fr_next = frp;
5174     else
5175 	frp->fr_parent->fr_child = frp;
5176 }
5177 
5178 /*
5179  * Remove a frame from a frame list.
5180  */
5181     static void
5182 frame_remove(frame_T *frp)
5183 {
5184     if (frp->fr_prev != NULL)
5185 	frp->fr_prev->fr_next = frp->fr_next;
5186     else
5187     {
5188 	frp->fr_parent->fr_child = frp->fr_next;
5189 	// special case: topframe->fr_child == frp
5190 	if (topframe->fr_child == frp)
5191 	    topframe->fr_child = frp->fr_next;
5192     }
5193     if (frp->fr_next != NULL)
5194 	frp->fr_next->fr_prev = frp->fr_prev;
5195 }
5196 
5197 /*
5198  * Allocate w_lines[] for window "wp".
5199  * Return FAIL for failure, OK for success.
5200  */
5201     int
5202 win_alloc_lines(win_T *wp)
5203 {
5204     wp->w_lines_valid = 0;
5205     wp->w_lines = ALLOC_CLEAR_MULT(wline_T, Rows );
5206     if (wp->w_lines == NULL)
5207 	return FAIL;
5208     return OK;
5209 }
5210 
5211 /*
5212  * free lsize arrays for a window
5213  */
5214     void
5215 win_free_lsize(win_T *wp)
5216 {
5217     // TODO: why would wp be NULL here?
5218     if (wp != NULL)
5219 	VIM_CLEAR(wp->w_lines);
5220 }
5221 
5222 /*
5223  * Called from win_new_shellsize() after Rows changed.
5224  * This only does the current tab page, others must be done when made active.
5225  */
5226     void
5227 shell_new_rows(void)
5228 {
5229     int		h = (int)ROWS_AVAIL;
5230 
5231     if (firstwin == NULL)	// not initialized yet
5232 	return;
5233     if (h < frame_minheight(topframe, NULL))
5234 	h = frame_minheight(topframe, NULL);
5235 
5236     // First try setting the heights of windows with 'winfixheight'.  If
5237     // that doesn't result in the right height, forget about that option.
5238     frame_new_height(topframe, h, FALSE, TRUE);
5239     if (!frame_check_height(topframe, h))
5240 	frame_new_height(topframe, h, FALSE, FALSE);
5241 
5242     (void)win_comp_pos();		// recompute w_winrow and w_wincol
5243     compute_cmdrow();
5244     curtab->tp_ch_used = p_ch;
5245 
5246 #if 0
5247     // Disabled: don't want making the screen smaller make a window larger.
5248     if (p_ea)
5249 	win_equal(curwin, FALSE, 'v');
5250 #endif
5251 }
5252 
5253 /*
5254  * Called from win_new_shellsize() after Columns changed.
5255  */
5256     void
5257 shell_new_columns(void)
5258 {
5259     if (firstwin == NULL)	// not initialized yet
5260 	return;
5261 
5262     // First try setting the widths of windows with 'winfixwidth'.  If that
5263     // doesn't result in the right width, forget about that option.
5264     frame_new_width(topframe, (int)Columns, FALSE, TRUE);
5265     if (!frame_check_width(topframe, Columns))
5266 	frame_new_width(topframe, (int)Columns, FALSE, FALSE);
5267 
5268     (void)win_comp_pos();		// recompute w_winrow and w_wincol
5269 #if 0
5270     // Disabled: don't want making the screen smaller make a window larger.
5271     if (p_ea)
5272 	win_equal(curwin, FALSE, 'h');
5273 #endif
5274 }
5275 
5276 #if defined(FEAT_CMDWIN) || defined(PROTO)
5277 /*
5278  * Save the size of all windows in "gap".
5279  */
5280     void
5281 win_size_save(garray_T *gap)
5282 
5283 {
5284     win_T	*wp;
5285 
5286     ga_init2(gap, (int)sizeof(int), 1);
5287     if (ga_grow(gap, win_count() * 2 + 1) == OK)
5288     {
5289 	// first entry is value of 'lines'
5290 	((int *)gap->ga_data)[gap->ga_len++] = Rows;
5291 
5292 	FOR_ALL_WINDOWS(wp)
5293 	{
5294 	    ((int *)gap->ga_data)[gap->ga_len++] =
5295 					       wp->w_width + wp->w_vsep_width;
5296 	    ((int *)gap->ga_data)[gap->ga_len++] = wp->w_height;
5297 	}
5298     }
5299 }
5300 
5301 /*
5302  * Restore window sizes, but only if the number of windows is still the same
5303  * and 'lines' didn't change.
5304  * Does not free the growarray.
5305  */
5306     void
5307 win_size_restore(garray_T *gap)
5308 {
5309     win_T	*wp;
5310     int		i, j;
5311 
5312     if (win_count() * 2 + 1 == gap->ga_len
5313 	    && ((int *)gap->ga_data)[0] == Rows)
5314     {
5315 	// The order matters, because frames contain other frames, but it's
5316 	// difficult to get right. The easy way out is to do it twice.
5317 	for (j = 0; j < 2; ++j)
5318 	{
5319 	    i = 1;
5320 	    FOR_ALL_WINDOWS(wp)
5321 	    {
5322 		frame_setwidth(wp->w_frame, ((int *)gap->ga_data)[i++]);
5323 		win_setheight_win(((int *)gap->ga_data)[i++], wp);
5324 	    }
5325 	}
5326 	// recompute the window positions
5327 	(void)win_comp_pos();
5328     }
5329 }
5330 #endif // FEAT_CMDWIN
5331 
5332 /*
5333  * Update the position for all windows, using the width and height of the
5334  * frames.
5335  * Returns the row just after the last window.
5336  */
5337     int
5338 win_comp_pos(void)
5339 {
5340     int		row = tabline_height();
5341     int		col = 0;
5342 
5343     frame_comp_pos(topframe, &row, &col);
5344     return row;
5345 }
5346 
5347 /*
5348  * Update the position of the windows in frame "topfrp", using the width and
5349  * height of the frames.
5350  * "*row" and "*col" are the top-left position of the frame.  They are updated
5351  * to the bottom-right position plus one.
5352  */
5353     static void
5354 frame_comp_pos(frame_T *topfrp, int *row, int *col)
5355 {
5356     win_T	*wp;
5357     frame_T	*frp;
5358     int		startcol;
5359     int		startrow;
5360     int		h;
5361 
5362     wp = topfrp->fr_win;
5363     if (wp != NULL)
5364     {
5365 	if (wp->w_winrow != *row || wp->w_wincol != *col)
5366 	{
5367 	    // position changed, redraw
5368 	    wp->w_winrow = *row;
5369 	    wp->w_wincol = *col;
5370 	    redraw_win_later(wp, NOT_VALID);
5371 	    wp->w_redr_status = TRUE;
5372 	}
5373 	// WinBar will not show if the window height is zero
5374 	h = VISIBLE_HEIGHT(wp) + wp->w_status_height;
5375 	*row += h > topfrp->fr_height ? topfrp->fr_height : h;
5376 	*col += wp->w_width + wp->w_vsep_width;
5377     }
5378     else
5379     {
5380 	startrow = *row;
5381 	startcol = *col;
5382 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
5383 	{
5384 	    if (topfrp->fr_layout == FR_ROW)
5385 		*row = startrow;	// all frames are at the same row
5386 	    else
5387 		*col = startcol;	// all frames are at the same col
5388 	    frame_comp_pos(frp, row, col);
5389 	}
5390     }
5391 }
5392 
5393 /*
5394  * Set current window height and take care of repositioning other windows to
5395  * fit around it.
5396  */
5397     void
5398 win_setheight(int height)
5399 {
5400     win_setheight_win(height, curwin);
5401 }
5402 
5403 /*
5404  * Set the window height of window "win" and take care of repositioning other
5405  * windows to fit around it.
5406  */
5407     void
5408 win_setheight_win(int height, win_T *win)
5409 {
5410     int		row;
5411 
5412     if (win == curwin)
5413     {
5414 	// Always keep current window at least one line high, even when
5415 	// 'winminheight' is zero.
5416 	if (height < p_wmh)
5417 	    height = p_wmh;
5418 	if (height == 0)
5419 	    height = 1;
5420 	height += WINBAR_HEIGHT(curwin);
5421     }
5422 
5423     frame_setheight(win->w_frame, height + win->w_status_height);
5424 
5425     // recompute the window positions
5426     row = win_comp_pos();
5427 
5428     /*
5429      * If there is extra space created between the last window and the command
5430      * line, clear it.
5431      */
5432     if (full_screen && msg_scrolled == 0 && row < cmdline_row)
5433 	screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5434     cmdline_row = row;
5435     msg_row = row;
5436     msg_col = 0;
5437 
5438     redraw_all_later(NOT_VALID);
5439 }
5440 
5441 /*
5442  * Set the height of a frame to "height" and take care that all frames and
5443  * windows inside it are resized.  Also resize frames on the left and right if
5444  * the are in the same FR_ROW frame.
5445  *
5446  * Strategy:
5447  * If the frame is part of a FR_COL frame, try fitting the frame in that
5448  * frame.  If that doesn't work (the FR_COL frame is too small), recursively
5449  * go to containing frames to resize them and make room.
5450  * If the frame is part of a FR_ROW frame, all frames must be resized as well.
5451  * Check for the minimal height of the FR_ROW frame.
5452  * At the top level we can also use change the command line height.
5453  */
5454     static void
5455 frame_setheight(frame_T *curfrp, int height)
5456 {
5457     int		room;		// total number of lines available
5458     int		take;		// number of lines taken from other windows
5459     int		room_cmdline;	// lines available from cmdline
5460     int		run;
5461     frame_T	*frp;
5462     int		h;
5463     int		room_reserved;
5464 
5465     // If the height already is the desired value, nothing to do.
5466     if (curfrp->fr_height == height)
5467 	return;
5468 
5469     if (curfrp->fr_parent == NULL)
5470     {
5471 	// topframe: can only change the command line
5472 	if (height > ROWS_AVAIL)
5473 	    height = ROWS_AVAIL;
5474 	if (height > 0)
5475 	    frame_new_height(curfrp, height, FALSE, FALSE);
5476     }
5477     else if (curfrp->fr_parent->fr_layout == FR_ROW)
5478     {
5479 	// Row of frames: Also need to resize frames left and right of this
5480 	// one.  First check for the minimal height of these.
5481 	h = frame_minheight(curfrp->fr_parent, NULL);
5482 	if (height < h)
5483 	    height = h;
5484 	frame_setheight(curfrp->fr_parent, height);
5485     }
5486     else
5487     {
5488 	/*
5489 	 * Column of frames: try to change only frames in this column.
5490 	 */
5491 	/*
5492 	 * Do this twice:
5493 	 * 1: compute room available, if it's not enough try resizing the
5494 	 *    containing frame.
5495 	 * 2: compute the room available and adjust the height to it.
5496 	 * Try not to reduce the height of a window with 'winfixheight' set.
5497 	 */
5498 	for (run = 1; run <= 2; ++run)
5499 	{
5500 	    room = 0;
5501 	    room_reserved = 0;
5502 	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
5503 	    {
5504 		if (frp != curfrp
5505 			&& frp->fr_win != NULL
5506 			&& frp->fr_win->w_p_wfh)
5507 		    room_reserved += frp->fr_height;
5508 		room += frp->fr_height;
5509 		if (frp != curfrp)
5510 		    room -= frame_minheight(frp, NULL);
5511 	    }
5512 	    if (curfrp->fr_width != Columns)
5513 		room_cmdline = 0;
5514 	    else
5515 	    {
5516 		room_cmdline = Rows - p_ch - (lastwin->w_winrow
5517 						+ VISIBLE_HEIGHT(lastwin)
5518 						+ lastwin->w_status_height);
5519 		if (room_cmdline < 0)
5520 		    room_cmdline = 0;
5521 	    }
5522 
5523 	    if (height <= room + room_cmdline)
5524 		break;
5525 	    if (run == 2 || curfrp->fr_width == Columns)
5526 	    {
5527 		if (height > room + room_cmdline)
5528 		    height = room + room_cmdline;
5529 		break;
5530 	    }
5531 	    frame_setheight(curfrp->fr_parent, height
5532 		+ frame_minheight(curfrp->fr_parent, NOWIN) - (int)p_wmh - 1);
5533 	}
5534 
5535 	/*
5536 	 * Compute the number of lines we will take from others frames (can be
5537 	 * negative!).
5538 	 */
5539 	take = height - curfrp->fr_height;
5540 
5541 	// If there is not enough room, also reduce the height of a window
5542 	// with 'winfixheight' set.
5543 	if (height > room + room_cmdline - room_reserved)
5544 	    room_reserved = room + room_cmdline - height;
5545 	// If there is only a 'winfixheight' window and making the
5546 	// window smaller, need to make the other window taller.
5547 	if (take < 0 && room - curfrp->fr_height < room_reserved)
5548 	    room_reserved = 0;
5549 
5550 	if (take > 0 && room_cmdline > 0)
5551 	{
5552 	    // use lines from cmdline first
5553 	    if (take < room_cmdline)
5554 		room_cmdline = take;
5555 	    take -= room_cmdline;
5556 	    topframe->fr_height += room_cmdline;
5557 	}
5558 
5559 	/*
5560 	 * set the current frame to the new height
5561 	 */
5562 	frame_new_height(curfrp, height, FALSE, FALSE);
5563 
5564 	/*
5565 	 * First take lines from the frames after the current frame.  If
5566 	 * that is not enough, takes lines from frames above the current
5567 	 * frame.
5568 	 */
5569 	for (run = 0; run < 2; ++run)
5570 	{
5571 	    if (run == 0)
5572 		frp = curfrp->fr_next;	// 1st run: start with next window
5573 	    else
5574 		frp = curfrp->fr_prev;	// 2nd run: start with prev window
5575 	    while (frp != NULL && take != 0)
5576 	    {
5577 		h = frame_minheight(frp, NULL);
5578 		if (room_reserved > 0
5579 			&& frp->fr_win != NULL
5580 			&& frp->fr_win->w_p_wfh)
5581 		{
5582 		    if (room_reserved >= frp->fr_height)
5583 			room_reserved -= frp->fr_height;
5584 		    else
5585 		    {
5586 			if (frp->fr_height - room_reserved > take)
5587 			    room_reserved = frp->fr_height - take;
5588 			take -= frp->fr_height - room_reserved;
5589 			frame_new_height(frp, room_reserved, FALSE, FALSE);
5590 			room_reserved = 0;
5591 		    }
5592 		}
5593 		else
5594 		{
5595 		    if (frp->fr_height - take < h)
5596 		    {
5597 			take -= frp->fr_height - h;
5598 			frame_new_height(frp, h, FALSE, FALSE);
5599 		    }
5600 		    else
5601 		    {
5602 			frame_new_height(frp, frp->fr_height - take,
5603 								FALSE, FALSE);
5604 			take = 0;
5605 		    }
5606 		}
5607 		if (run == 0)
5608 		    frp = frp->fr_next;
5609 		else
5610 		    frp = frp->fr_prev;
5611 	    }
5612 	}
5613     }
5614 }
5615 
5616 /*
5617  * Set current window width and take care of repositioning other windows to
5618  * fit around it.
5619  */
5620     void
5621 win_setwidth(int width)
5622 {
5623     win_setwidth_win(width, curwin);
5624 }
5625 
5626     void
5627 win_setwidth_win(int width, win_T *wp)
5628 {
5629     // Always keep current window at least one column wide, even when
5630     // 'winminwidth' is zero.
5631     if (wp == curwin)
5632     {
5633 	if (width < p_wmw)
5634 	    width = p_wmw;
5635 	if (width == 0)
5636 	    width = 1;
5637     }
5638 
5639     frame_setwidth(wp->w_frame, width + wp->w_vsep_width);
5640 
5641     // recompute the window positions
5642     (void)win_comp_pos();
5643 
5644     redraw_all_later(NOT_VALID);
5645 }
5646 
5647 /*
5648  * Set the width of a frame to "width" and take care that all frames and
5649  * windows inside it are resized.  Also resize frames above and below if the
5650  * are in the same FR_ROW frame.
5651  *
5652  * Strategy is similar to frame_setheight().
5653  */
5654     static void
5655 frame_setwidth(frame_T *curfrp, int width)
5656 {
5657     int		room;		// total number of lines available
5658     int		take;		// number of lines taken from other windows
5659     int		run;
5660     frame_T	*frp;
5661     int		w;
5662     int		room_reserved;
5663 
5664     // If the width already is the desired value, nothing to do.
5665     if (curfrp->fr_width == width)
5666 	return;
5667 
5668     if (curfrp->fr_parent == NULL)
5669 	// topframe: can't change width
5670 	return;
5671 
5672     if (curfrp->fr_parent->fr_layout == FR_COL)
5673     {
5674 	// Column of frames: Also need to resize frames above and below of
5675 	// this one.  First check for the minimal width of these.
5676 	w = frame_minwidth(curfrp->fr_parent, NULL);
5677 	if (width < w)
5678 	    width = w;
5679 	frame_setwidth(curfrp->fr_parent, width);
5680     }
5681     else
5682     {
5683 	/*
5684 	 * Row of frames: try to change only frames in this row.
5685 	 *
5686 	 * Do this twice:
5687 	 * 1: compute room available, if it's not enough try resizing the
5688 	 *    containing frame.
5689 	 * 2: compute the room available and adjust the width to it.
5690 	 */
5691 	for (run = 1; run <= 2; ++run)
5692 	{
5693 	    room = 0;
5694 	    room_reserved = 0;
5695 	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
5696 	    {
5697 		if (frp != curfrp
5698 			&& frp->fr_win != NULL
5699 			&& frp->fr_win->w_p_wfw)
5700 		    room_reserved += frp->fr_width;
5701 		room += frp->fr_width;
5702 		if (frp != curfrp)
5703 		    room -= frame_minwidth(frp, NULL);
5704 	    }
5705 
5706 	    if (width <= room)
5707 		break;
5708 	    if (run == 2 || curfrp->fr_height >= ROWS_AVAIL)
5709 	    {
5710 		if (width > room)
5711 		    width = room;
5712 		break;
5713 	    }
5714 	    frame_setwidth(curfrp->fr_parent, width
5715 		 + frame_minwidth(curfrp->fr_parent, NOWIN) - (int)p_wmw - 1);
5716 	}
5717 
5718 	/*
5719 	 * Compute the number of lines we will take from others frames (can be
5720 	 * negative!).
5721 	 */
5722 	take = width - curfrp->fr_width;
5723 
5724 	// If there is not enough room, also reduce the width of a window
5725 	// with 'winfixwidth' set.
5726 	if (width > room - room_reserved)
5727 	    room_reserved = room - width;
5728 	// If there is only a 'winfixwidth' window and making the
5729 	// window smaller, need to make the other window narrower.
5730 	if (take < 0 && room - curfrp->fr_width < room_reserved)
5731 	    room_reserved = 0;
5732 
5733 	/*
5734 	 * set the current frame to the new width
5735 	 */
5736 	frame_new_width(curfrp, width, FALSE, FALSE);
5737 
5738 	/*
5739 	 * First take lines from the frames right of the current frame.  If
5740 	 * that is not enough, takes lines from frames left of the current
5741 	 * frame.
5742 	 */
5743 	for (run = 0; run < 2; ++run)
5744 	{
5745 	    if (run == 0)
5746 		frp = curfrp->fr_next;	// 1st run: start with next window
5747 	    else
5748 		frp = curfrp->fr_prev;	// 2nd run: start with prev window
5749 	    while (frp != NULL && take != 0)
5750 	    {
5751 		w = frame_minwidth(frp, NULL);
5752 		if (room_reserved > 0
5753 			&& frp->fr_win != NULL
5754 			&& frp->fr_win->w_p_wfw)
5755 		{
5756 		    if (room_reserved >= frp->fr_width)
5757 			room_reserved -= frp->fr_width;
5758 		    else
5759 		    {
5760 			if (frp->fr_width - room_reserved > take)
5761 			    room_reserved = frp->fr_width - take;
5762 			take -= frp->fr_width - room_reserved;
5763 			frame_new_width(frp, room_reserved, FALSE, FALSE);
5764 			room_reserved = 0;
5765 		    }
5766 		}
5767 		else
5768 		{
5769 		    if (frp->fr_width - take < w)
5770 		    {
5771 			take -= frp->fr_width - w;
5772 			frame_new_width(frp, w, FALSE, FALSE);
5773 		    }
5774 		    else
5775 		    {
5776 			frame_new_width(frp, frp->fr_width - take,
5777 								FALSE, FALSE);
5778 			take = 0;
5779 		    }
5780 		}
5781 		if (run == 0)
5782 		    frp = frp->fr_next;
5783 		else
5784 		    frp = frp->fr_prev;
5785 	    }
5786 	}
5787     }
5788 }
5789 
5790 /*
5791  * Check 'winminheight' for a valid value and reduce it if needed.
5792  */
5793     void
5794 win_setminheight(void)
5795 {
5796     int		room;
5797     int		needed;
5798     int		first = TRUE;
5799 
5800     // loop until there is a 'winminheight' that is possible
5801     while (p_wmh > 0)
5802     {
5803 	room = Rows - p_ch;
5804 	needed = frame_minheight(topframe, NULL);
5805 	if (room >= needed)
5806 	    break;
5807 	--p_wmh;
5808 	if (first)
5809 	{
5810 	    emsg(_(e_noroom));
5811 	    first = FALSE;
5812 	}
5813     }
5814 }
5815 
5816 /*
5817  * Check 'winminwidth' for a valid value and reduce it if needed.
5818  */
5819     void
5820 win_setminwidth(void)
5821 {
5822     int		room;
5823     int		needed;
5824     int		first = TRUE;
5825 
5826     // loop until there is a 'winminheight' that is possible
5827     while (p_wmw > 0)
5828     {
5829 	room = Columns;
5830 	needed = frame_minwidth(topframe, NULL);
5831 	if (room >= needed)
5832 	    break;
5833 	--p_wmw;
5834 	if (first)
5835 	{
5836 	    emsg(_(e_noroom));
5837 	    first = FALSE;
5838 	}
5839     }
5840 }
5841 
5842 /*
5843  * Status line of dragwin is dragged "offset" lines down (negative is up).
5844  */
5845     void
5846 win_drag_status_line(win_T *dragwin, int offset)
5847 {
5848     frame_T	*curfr;
5849     frame_T	*fr;
5850     int		room;
5851     int		row;
5852     int		up;	// if TRUE, drag status line up, otherwise down
5853     int		n;
5854 
5855     fr = dragwin->w_frame;
5856     curfr = fr;
5857     if (fr != topframe)		// more than one window
5858     {
5859 	fr = fr->fr_parent;
5860 	// When the parent frame is not a column of frames, its parent should
5861 	// be.
5862 	if (fr->fr_layout != FR_COL)
5863 	{
5864 	    curfr = fr;
5865 	    if (fr != topframe)	// only a row of windows, may drag statusline
5866 		fr = fr->fr_parent;
5867 	}
5868     }
5869 
5870     // If this is the last frame in a column, may want to resize the parent
5871     // frame instead (go two up to skip a row of frames).
5872     while (curfr != topframe && curfr->fr_next == NULL)
5873     {
5874 	if (fr != topframe)
5875 	    fr = fr->fr_parent;
5876 	curfr = fr;
5877 	if (fr != topframe)
5878 	    fr = fr->fr_parent;
5879     }
5880 
5881     if (offset < 0) // drag up
5882     {
5883 	up = TRUE;
5884 	offset = -offset;
5885 	// sum up the room of the current frame and above it
5886 	if (fr == curfr)
5887 	{
5888 	    // only one window
5889 	    room = fr->fr_height - frame_minheight(fr, NULL);
5890 	}
5891 	else
5892 	{
5893 	    room = 0;
5894 	    for (fr = fr->fr_child; ; fr = fr->fr_next)
5895 	    {
5896 		room += fr->fr_height - frame_minheight(fr, NULL);
5897 		if (fr == curfr)
5898 		    break;
5899 	    }
5900 	}
5901 	fr = curfr->fr_next;		// put fr at frame that grows
5902     }
5903     else    // drag down
5904     {
5905 	up = FALSE;
5906 	/*
5907 	 * Only dragging the last status line can reduce p_ch.
5908 	 */
5909 	room = Rows - cmdline_row;
5910 	if (curfr->fr_next == NULL)
5911 	    room -= 1;
5912 	else
5913 	    room -= p_ch;
5914 	if (room < 0)
5915 	    room = 0;
5916 	// sum up the room of frames below of the current one
5917 	FOR_ALL_FRAMES(fr, curfr->fr_next)
5918 	    room += fr->fr_height - frame_minheight(fr, NULL);
5919 	fr = curfr;			// put fr at window that grows
5920     }
5921 
5922     if (room < offset)		// Not enough room
5923 	offset = room;		// Move as far as we can
5924     if (offset <= 0)
5925 	return;
5926 
5927     /*
5928      * Grow frame fr by "offset" lines.
5929      * Doesn't happen when dragging the last status line up.
5930      */
5931     if (fr != NULL)
5932 	frame_new_height(fr, fr->fr_height + offset, up, FALSE);
5933 
5934     if (up)
5935 	fr = curfr;		// current frame gets smaller
5936     else
5937 	fr = curfr->fr_next;	// next frame gets smaller
5938 
5939     /*
5940      * Now make the other frames smaller.
5941      */
5942     while (fr != NULL && offset > 0)
5943     {
5944 	n = frame_minheight(fr, NULL);
5945 	if (fr->fr_height - offset <= n)
5946 	{
5947 	    offset -= fr->fr_height - n;
5948 	    frame_new_height(fr, n, !up, FALSE);
5949 	}
5950 	else
5951 	{
5952 	    frame_new_height(fr, fr->fr_height - offset, !up, FALSE);
5953 	    break;
5954 	}
5955 	if (up)
5956 	    fr = fr->fr_prev;
5957 	else
5958 	    fr = fr->fr_next;
5959     }
5960     row = win_comp_pos();
5961     screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5962     cmdline_row = row;
5963     p_ch = Rows - cmdline_row;
5964     if (p_ch < 1)
5965 	p_ch = 1;
5966     curtab->tp_ch_used = p_ch;
5967     redraw_all_later(SOME_VALID);
5968     showmode();
5969 }
5970 
5971 /*
5972  * Separator line of dragwin is dragged "offset" lines right (negative is left).
5973  */
5974     void
5975 win_drag_vsep_line(win_T *dragwin, int offset)
5976 {
5977     frame_T	*curfr;
5978     frame_T	*fr;
5979     int		room;
5980     int		left;	// if TRUE, drag separator line left, otherwise right
5981     int		n;
5982 
5983     fr = dragwin->w_frame;
5984     if (fr == topframe)		// only one window (cannot happen?)
5985 	return;
5986     curfr = fr;
5987     fr = fr->fr_parent;
5988     // When the parent frame is not a row of frames, its parent should be.
5989     if (fr->fr_layout != FR_ROW)
5990     {
5991 	if (fr == topframe)	// only a column of windows (cannot happen?)
5992 	    return;
5993 	curfr = fr;
5994 	fr = fr->fr_parent;
5995     }
5996 
5997     // If this is the last frame in a row, may want to resize a parent
5998     // frame instead.
5999     while (curfr->fr_next == NULL)
6000     {
6001 	if (fr == topframe)
6002 	    break;
6003 	curfr = fr;
6004 	fr = fr->fr_parent;
6005 	if (fr != topframe)
6006 	{
6007 	    curfr = fr;
6008 	    fr = fr->fr_parent;
6009 	}
6010     }
6011 
6012     if (offset < 0) // drag left
6013     {
6014 	left = TRUE;
6015 	offset = -offset;
6016 	// sum up the room of the current frame and left of it
6017 	room = 0;
6018 	for (fr = fr->fr_child; ; fr = fr->fr_next)
6019 	{
6020 	    room += fr->fr_width - frame_minwidth(fr, NULL);
6021 	    if (fr == curfr)
6022 		break;
6023 	}
6024 	fr = curfr->fr_next;		// put fr at frame that grows
6025     }
6026     else    // drag right
6027     {
6028 	left = FALSE;
6029 	// sum up the room of frames right of the current one
6030 	room = 0;
6031 	FOR_ALL_FRAMES(fr, curfr->fr_next)
6032 	    room += fr->fr_width - frame_minwidth(fr, NULL);
6033 	fr = curfr;			// put fr at window that grows
6034     }
6035 
6036     if (room < offset)		// Not enough room
6037 	offset = room;		// Move as far as we can
6038     if (offset <= 0)		// No room at all, quit.
6039 	return;
6040     if (fr == NULL)
6041 	return;			// Safety check, should not happen.
6042 
6043     // grow frame fr by offset lines
6044     frame_new_width(fr, fr->fr_width + offset, left, FALSE);
6045 
6046     // shrink other frames: current and at the left or at the right
6047     if (left)
6048 	fr = curfr;		// current frame gets smaller
6049     else
6050 	fr = curfr->fr_next;	// next frame gets smaller
6051 
6052     while (fr != NULL && offset > 0)
6053     {
6054 	n = frame_minwidth(fr, NULL);
6055 	if (fr->fr_width - offset <= n)
6056 	{
6057 	    offset -= fr->fr_width - n;
6058 	    frame_new_width(fr, n, !left, FALSE);
6059 	}
6060 	else
6061 	{
6062 	    frame_new_width(fr, fr->fr_width - offset, !left, FALSE);
6063 	    break;
6064 	}
6065 	if (left)
6066 	    fr = fr->fr_prev;
6067 	else
6068 	    fr = fr->fr_next;
6069     }
6070     (void)win_comp_pos();
6071     redraw_all_later(NOT_VALID);
6072 }
6073 
6074 #define FRACTION_MULT	16384L
6075 
6076 /*
6077  * Set wp->w_fraction for the current w_wrow and w_height.
6078  * Has no effect when the window is less than two lines.
6079  */
6080     void
6081 set_fraction(win_T *wp)
6082 {
6083     if (wp->w_height > 1)
6084 	// When cursor is in the first line the percentage is computed as if
6085 	// it's halfway that line.  Thus with two lines it is 25%, with three
6086 	// lines 17%, etc.  Similarly for the last line: 75%, 83%, etc.
6087 	wp->w_fraction = ((long)wp->w_wrow * FRACTION_MULT
6088 				     + FRACTION_MULT / 2) / (long)wp->w_height;
6089 }
6090 
6091 /*
6092  * Set the height of a window.
6093  * "height" excludes any window toolbar.
6094  * This takes care of the things inside the window, not what happens to the
6095  * window position, the frame or to other windows.
6096  */
6097     void
6098 win_new_height(win_T *wp, int height)
6099 {
6100     int		prev_height = wp->w_height;
6101 
6102     // Don't want a negative height.  Happens when splitting a tiny window.
6103     // Will equalize heights soon to fix it.
6104     if (height < 0)
6105 	height = 0;
6106     if (wp->w_height == height)
6107 	return;	    // nothing to do
6108 
6109     if (wp->w_height > 0)
6110     {
6111 	if (wp == curwin)
6112 	    // w_wrow needs to be valid. When setting 'laststatus' this may
6113 	    // call win_new_height() recursively.
6114 	    validate_cursor();
6115 	if (wp->w_height != prev_height)
6116 	    return;  // Recursive call already changed the size, bail out here
6117 		     //	to avoid the following to mess things up.
6118 	if (wp->w_wrow != wp->w_prev_fraction_row)
6119 	    set_fraction(wp);
6120     }
6121 
6122     wp->w_height = height;
6123     wp->w_skipcol = 0;
6124 
6125     // There is no point in adjusting the scroll position when exiting.  Some
6126     // values might be invalid.
6127     if (!exiting)
6128 	scroll_to_fraction(wp, prev_height);
6129 }
6130 
6131     void
6132 scroll_to_fraction(win_T *wp, int prev_height)
6133 {
6134     linenr_T	lnum;
6135     int		sline, line_size;
6136     int		height = wp->w_height;
6137 
6138     // Don't change w_topline in any of these cases:
6139     // - window height is 0
6140     // - 'scrollbind' is set and this isn't the current window
6141     // - window height is sufficient to display the whole buffer and first line
6142     //   is visible.
6143     if (height > 0
6144         && (!wp->w_p_scb || wp == curwin)
6145         && (height < wp->w_buffer->b_ml.ml_line_count || wp->w_topline > 1))
6146     {
6147 	/*
6148 	 * Find a value for w_topline that shows the cursor at the same
6149 	 * relative position in the window as before (more or less).
6150 	 */
6151 	lnum = wp->w_cursor.lnum;
6152 	if (lnum < 1)		// can happen when starting up
6153 	    lnum = 1;
6154 	wp->w_wrow = ((long)wp->w_fraction * (long)height - 1L)
6155 							       / FRACTION_MULT;
6156 	line_size = plines_win_col(wp, lnum, (long)(wp->w_cursor.col)) - 1;
6157 	sline = wp->w_wrow - line_size;
6158 
6159 	if (sline >= 0)
6160 	{
6161 	    // Make sure the whole cursor line is visible, if possible.
6162 	    int rows = plines_win(wp, lnum, FALSE);
6163 
6164 	    if (sline > wp->w_height - rows)
6165 	    {
6166 		sline = wp->w_height - rows;
6167 		wp->w_wrow -= rows - line_size;
6168 	    }
6169 	}
6170 
6171 	if (sline < 0)
6172 	{
6173 	    /*
6174 	     * Cursor line would go off top of screen if w_wrow was this high.
6175 	     * Make cursor line the first line in the window.  If not enough
6176 	     * room use w_skipcol;
6177 	     */
6178 	    wp->w_wrow = line_size;
6179 	    if (wp->w_wrow >= wp->w_height
6180 				       && (wp->w_width - win_col_off(wp)) > 0)
6181 	    {
6182 		wp->w_skipcol += wp->w_width - win_col_off(wp);
6183 		--wp->w_wrow;
6184 		while (wp->w_wrow >= wp->w_height)
6185 		{
6186 		    wp->w_skipcol += wp->w_width - win_col_off(wp)
6187 							   + win_col_off2(wp);
6188 		    --wp->w_wrow;
6189 		}
6190 	    }
6191 	}
6192 	else if (sline > 0)
6193 	{
6194 	    while (sline > 0 && lnum > 1)
6195 	    {
6196 #ifdef FEAT_FOLDING
6197 		hasFoldingWin(wp, lnum, &lnum, NULL, TRUE, NULL);
6198 		if (lnum == 1)
6199 		{
6200 		    // first line in buffer is folded
6201 		    line_size = 1;
6202 		    --sline;
6203 		    break;
6204 		}
6205 #endif
6206 		--lnum;
6207 #ifdef FEAT_DIFF
6208 		if (lnum == wp->w_topline)
6209 		    line_size = plines_win_nofill(wp, lnum, TRUE)
6210 							      + wp->w_topfill;
6211 		else
6212 #endif
6213 		    line_size = plines_win(wp, lnum, TRUE);
6214 		sline -= line_size;
6215 	    }
6216 
6217 	    if (sline < 0)
6218 	    {
6219 		/*
6220 		 * Line we want at top would go off top of screen.  Use next
6221 		 * line instead.
6222 		 */
6223 #ifdef FEAT_FOLDING
6224 		hasFoldingWin(wp, lnum, NULL, &lnum, TRUE, NULL);
6225 #endif
6226 		lnum++;
6227 		wp->w_wrow -= line_size + sline;
6228 	    }
6229 	    else if (sline > 0)
6230 	    {
6231 		// First line of file reached, use that as topline.
6232 		lnum = 1;
6233 		wp->w_wrow -= sline;
6234 	    }
6235 	}
6236 	set_topline(wp, lnum);
6237     }
6238 
6239     if (wp == curwin)
6240     {
6241 	if (get_scrolloff_value())
6242 	    update_topline();
6243 	curs_columns(FALSE);	// validate w_wrow
6244     }
6245     if (prev_height > 0)
6246 	wp->w_prev_fraction_row = wp->w_wrow;
6247 
6248     win_comp_scroll(wp);
6249     redraw_win_later(wp, SOME_VALID);
6250     wp->w_redr_status = TRUE;
6251     invalidate_botline_win(wp);
6252 }
6253 
6254 /*
6255  * Set the width of a window.
6256  */
6257     void
6258 win_new_width(win_T *wp, int width)
6259 {
6260     wp->w_width = width;
6261     wp->w_lines_valid = 0;
6262     changed_line_abv_curs_win(wp);
6263     invalidate_botline_win(wp);
6264     if (wp == curwin)
6265     {
6266 	update_topline();
6267 	curs_columns(TRUE);	// validate w_wrow
6268     }
6269     redraw_win_later(wp, NOT_VALID);
6270     wp->w_redr_status = TRUE;
6271 }
6272 
6273     void
6274 win_comp_scroll(win_T *wp)
6275 {
6276     wp->w_p_scr = ((unsigned)wp->w_height >> 1);
6277     if (wp->w_p_scr == 0)
6278 	wp->w_p_scr = 1;
6279 }
6280 
6281 /*
6282  * command_height: called whenever p_ch has been changed
6283  */
6284     void
6285 command_height(void)
6286 {
6287     int		h;
6288     frame_T	*frp;
6289     int		old_p_ch = curtab->tp_ch_used;
6290 
6291     // Use the value of p_ch that we remembered.  This is needed for when the
6292     // GUI starts up, we can't be sure in what order things happen.  And when
6293     // p_ch was changed in another tab page.
6294     curtab->tp_ch_used = p_ch;
6295 
6296     // Find bottom frame with width of screen.
6297     frp = lastwin->w_frame;
6298     while (frp->fr_width != Columns && frp->fr_parent != NULL)
6299 	frp = frp->fr_parent;
6300 
6301     // Avoid changing the height of a window with 'winfixheight' set.
6302     while (frp->fr_prev != NULL && frp->fr_layout == FR_LEAF
6303 						      && frp->fr_win->w_p_wfh)
6304 	frp = frp->fr_prev;
6305 
6306     if (starting != NO_SCREEN)
6307     {
6308 	cmdline_row = Rows - p_ch;
6309 
6310 	if (p_ch > old_p_ch)		    // p_ch got bigger
6311 	{
6312 	    while (p_ch > old_p_ch)
6313 	    {
6314 		if (frp == NULL)
6315 		{
6316 		    emsg(_(e_noroom));
6317 		    p_ch = old_p_ch;
6318 		    curtab->tp_ch_used = p_ch;
6319 		    cmdline_row = Rows - p_ch;
6320 		    break;
6321 		}
6322 		h = frp->fr_height - frame_minheight(frp, NULL);
6323 		if (h > p_ch - old_p_ch)
6324 		    h = p_ch - old_p_ch;
6325 		old_p_ch += h;
6326 		frame_add_height(frp, -h);
6327 		frp = frp->fr_prev;
6328 	    }
6329 
6330 	    // Recompute window positions.
6331 	    (void)win_comp_pos();
6332 
6333 	    // clear the lines added to cmdline
6334 	    if (full_screen)
6335 		screen_fill((int)(cmdline_row), (int)Rows, 0,
6336 						   (int)Columns, ' ', ' ', 0);
6337 	    msg_row = cmdline_row;
6338 	    redraw_cmdline = TRUE;
6339 	    return;
6340 	}
6341 
6342 	if (msg_row < cmdline_row)
6343 	    msg_row = cmdline_row;
6344 	redraw_cmdline = TRUE;
6345     }
6346     frame_add_height(frp, (int)(old_p_ch - p_ch));
6347 
6348     // Recompute window positions.
6349     if (frp != lastwin->w_frame)
6350 	(void)win_comp_pos();
6351 }
6352 
6353 /*
6354  * Resize frame "frp" to be "n" lines higher (negative for less high).
6355  * Also resize the frames it is contained in.
6356  */
6357     static void
6358 frame_add_height(frame_T *frp, int n)
6359 {
6360     frame_new_height(frp, frp->fr_height + n, FALSE, FALSE);
6361     for (;;)
6362     {
6363 	frp = frp->fr_parent;
6364 	if (frp == NULL)
6365 	    break;
6366 	frp->fr_height += n;
6367     }
6368 }
6369 
6370 /*
6371  * Add or remove a status line for the bottom window(s), according to the
6372  * value of 'laststatus'.
6373  */
6374     void
6375 last_status(
6376     int		morewin)	// pretend there are two or more windows
6377 {
6378     // Don't make a difference between horizontal or vertical split.
6379     last_status_rec(topframe, (p_ls == 2
6380 			  || (p_ls == 1 && (morewin || !ONE_WINDOW))));
6381 }
6382 
6383     static void
6384 last_status_rec(frame_T *fr, int statusline)
6385 {
6386     frame_T	*fp;
6387     win_T	*wp;
6388 
6389     if (fr->fr_layout == FR_LEAF)
6390     {
6391 	wp = fr->fr_win;
6392 	if (wp->w_status_height != 0 && !statusline)
6393 	{
6394 	    // remove status line
6395 	    win_new_height(wp, wp->w_height + 1);
6396 	    wp->w_status_height = 0;
6397 	    comp_col();
6398 	}
6399 	else if (wp->w_status_height == 0 && statusline)
6400 	{
6401 	    // Find a frame to take a line from.
6402 	    fp = fr;
6403 	    while (fp->fr_height <= frame_minheight(fp, NULL))
6404 	    {
6405 		if (fp == topframe)
6406 		{
6407 		    emsg(_(e_noroom));
6408 		    return;
6409 		}
6410 		// In a column of frames: go to frame above.  If already at
6411 		// the top or in a row of frames: go to parent.
6412 		if (fp->fr_parent->fr_layout == FR_COL && fp->fr_prev != NULL)
6413 		    fp = fp->fr_prev;
6414 		else
6415 		    fp = fp->fr_parent;
6416 	    }
6417 	    wp->w_status_height = 1;
6418 	    if (fp != fr)
6419 	    {
6420 		frame_new_height(fp, fp->fr_height - 1, FALSE, FALSE);
6421 		frame_fix_height(wp);
6422 		(void)win_comp_pos();
6423 	    }
6424 	    else
6425 		win_new_height(wp, wp->w_height - 1);
6426 	    comp_col();
6427 	    redraw_all_later(SOME_VALID);
6428 	}
6429     }
6430     else if (fr->fr_layout == FR_ROW)
6431     {
6432 	// vertically split windows, set status line for each one
6433 	FOR_ALL_FRAMES(fp, fr->fr_child)
6434 	    last_status_rec(fp, statusline);
6435     }
6436     else
6437     {
6438 	// horizontally split window, set status line for last one
6439 	for (fp = fr->fr_child; fp->fr_next != NULL; fp = fp->fr_next)
6440 	    ;
6441 	last_status_rec(fp, statusline);
6442     }
6443 }
6444 
6445 /*
6446  * Return the number of lines used by the tab page line.
6447  */
6448     int
6449 tabline_height(void)
6450 {
6451 #ifdef FEAT_GUI_TABLINE
6452     // When the GUI has the tabline then this always returns zero.
6453     if (gui_use_tabline())
6454 	return 0;
6455 #endif
6456     switch (p_stal)
6457     {
6458 	case 0: return 0;
6459 	case 1: return (first_tabpage->tp_next == NULL) ? 0 : 1;
6460     }
6461     return 1;
6462 }
6463 
6464 /*
6465  * Return the minimal number of rows that is needed on the screen to display
6466  * the current number of windows.
6467  */
6468     int
6469 min_rows(void)
6470 {
6471     int		total;
6472     tabpage_T	*tp;
6473     int		n;
6474 
6475     if (firstwin == NULL)	// not initialized yet
6476 	return MIN_LINES;
6477 
6478     total = 0;
6479     FOR_ALL_TABPAGES(tp)
6480     {
6481 	n = frame_minheight(tp->tp_topframe, NULL);
6482 	if (total < n)
6483 	    total = n;
6484     }
6485     total += tabline_height();
6486     total += 1;		// count the room for the command line
6487     return total;
6488 }
6489 
6490 /*
6491  * Return TRUE if there is only one window and only one tab page, not
6492  * counting a help or preview window, unless it is the current window.
6493  * Does not count unlisted windows.
6494  */
6495     int
6496 only_one_window(void)
6497 {
6498     int		count = 0;
6499     win_T	*wp;
6500 
6501 #if defined(FEAT_PROP_POPUP)
6502     // If the current window is a popup then there always is another window.
6503     if (popup_is_popup(curwin))
6504 	return FALSE;
6505 #endif
6506 
6507     // If there is another tab page there always is another window.
6508     if (first_tabpage->tp_next != NULL)
6509 	return FALSE;
6510 
6511     FOR_ALL_WINDOWS(wp)
6512 	if (wp->w_buffer != NULL
6513 		&& (!((bt_help(wp->w_buffer) && !bt_help(curbuf))
6514 # ifdef FEAT_QUICKFIX
6515 		    || wp->w_p_pvw
6516 # endif
6517 	     ) || wp == curwin) && wp != aucmd_win)
6518 	    ++count;
6519     return (count <= 1);
6520 }
6521 
6522 /*
6523  * Correct the cursor line number in other windows.  Used after changing the
6524  * current buffer, and before applying autocommands.
6525  * When "do_curwin" is TRUE, also check current window.
6526  */
6527     void
6528 check_lnums(int do_curwin)
6529 {
6530     win_T	*wp;
6531     tabpage_T	*tp;
6532 
6533     FOR_ALL_TAB_WINDOWS(tp, wp)
6534 	if ((do_curwin || wp != curwin) && wp->w_buffer == curbuf)
6535 	{
6536 	    // save the original cursor position and topline
6537 	    wp->w_save_cursor.w_cursor_save = wp->w_cursor;
6538 	    wp->w_save_cursor.w_topline_save = wp->w_topline;
6539 
6540 	    if (wp->w_cursor.lnum > curbuf->b_ml.ml_line_count)
6541 		wp->w_cursor.lnum = curbuf->b_ml.ml_line_count;
6542 	    if (wp->w_topline > curbuf->b_ml.ml_line_count)
6543 		wp->w_topline = curbuf->b_ml.ml_line_count;
6544 
6545 	    // save the corrected cursor position and topline
6546 	    wp->w_save_cursor.w_cursor_corr = wp->w_cursor;
6547 	    wp->w_save_cursor.w_topline_corr = wp->w_topline;
6548 	}
6549 }
6550 
6551 /*
6552  * Reset cursor and topline to its stored values from check_lnums().
6553  * check_lnums() must have been called first!
6554  */
6555     void
6556 reset_lnums()
6557 {
6558     win_T	*wp;
6559     tabpage_T	*tp;
6560 
6561     FOR_ALL_TAB_WINDOWS(tp, wp)
6562 	if (wp->w_buffer == curbuf)
6563 	{
6564 	    // Restore the value if the autocommand didn't change it.
6565 	    if (EQUAL_POS(wp->w_save_cursor.w_cursor_corr, wp->w_cursor))
6566 		wp->w_cursor = wp->w_save_cursor.w_cursor_save;
6567 	    if (wp->w_save_cursor.w_topline_corr == wp->w_topline)
6568 		wp->w_topline = wp->w_save_cursor.w_topline_save;
6569 	}
6570 }
6571 
6572 /*
6573  * A snapshot of the window sizes, to restore them after closing the help
6574  * window.
6575  * Only these fields are used:
6576  * fr_layout
6577  * fr_width
6578  * fr_height
6579  * fr_next
6580  * fr_child
6581  * fr_win (only valid for the old curwin, NULL otherwise)
6582  */
6583 
6584 /*
6585  * Create a snapshot of the current frame sizes.
6586  */
6587     void
6588 make_snapshot(int idx)
6589 {
6590     clear_snapshot(curtab, idx);
6591     make_snapshot_rec(topframe, &curtab->tp_snapshot[idx]);
6592 }
6593 
6594     static void
6595 make_snapshot_rec(frame_T *fr, frame_T **frp)
6596 {
6597     *frp = ALLOC_CLEAR_ONE(frame_T);
6598     if (*frp == NULL)
6599 	return;
6600     (*frp)->fr_layout = fr->fr_layout;
6601     (*frp)->fr_width = fr->fr_width;
6602     (*frp)->fr_height = fr->fr_height;
6603     if (fr->fr_next != NULL)
6604 	make_snapshot_rec(fr->fr_next, &((*frp)->fr_next));
6605     if (fr->fr_child != NULL)
6606 	make_snapshot_rec(fr->fr_child, &((*frp)->fr_child));
6607     if (fr->fr_layout == FR_LEAF && fr->fr_win == curwin)
6608 	(*frp)->fr_win = curwin;
6609 }
6610 
6611 /*
6612  * Remove any existing snapshot.
6613  */
6614     static void
6615 clear_snapshot(tabpage_T *tp, int idx)
6616 {
6617     clear_snapshot_rec(tp->tp_snapshot[idx]);
6618     tp->tp_snapshot[idx] = NULL;
6619 }
6620 
6621     static void
6622 clear_snapshot_rec(frame_T *fr)
6623 {
6624     if (fr != NULL)
6625     {
6626 	clear_snapshot_rec(fr->fr_next);
6627 	clear_snapshot_rec(fr->fr_child);
6628 	vim_free(fr);
6629     }
6630 }
6631 
6632 /*
6633  * Restore a previously created snapshot, if there is any.
6634  * This is only done if the screen size didn't change and the window layout is
6635  * still the same.
6636  */
6637     void
6638 restore_snapshot(
6639     int		idx,
6640     int		close_curwin)	    // closing current window
6641 {
6642     win_T	*wp;
6643 
6644     if (curtab->tp_snapshot[idx] != NULL
6645 	    && curtab->tp_snapshot[idx]->fr_width == topframe->fr_width
6646 	    && curtab->tp_snapshot[idx]->fr_height == topframe->fr_height
6647 	    && check_snapshot_rec(curtab->tp_snapshot[idx], topframe) == OK)
6648     {
6649 	wp = restore_snapshot_rec(curtab->tp_snapshot[idx], topframe);
6650 	win_comp_pos();
6651 	if (wp != NULL && close_curwin)
6652 	    win_goto(wp);
6653 	redraw_all_later(NOT_VALID);
6654     }
6655     clear_snapshot(curtab, idx);
6656 }
6657 
6658 /*
6659  * Check if frames "sn" and "fr" have the same layout, same following frames
6660  * and same children.  And the window pointer is valid.
6661  */
6662     static int
6663 check_snapshot_rec(frame_T *sn, frame_T *fr)
6664 {
6665     if (sn->fr_layout != fr->fr_layout
6666 	    || (sn->fr_next == NULL) != (fr->fr_next == NULL)
6667 	    || (sn->fr_child == NULL) != (fr->fr_child == NULL)
6668 	    || (sn->fr_next != NULL
6669 		&& check_snapshot_rec(sn->fr_next, fr->fr_next) == FAIL)
6670 	    || (sn->fr_child != NULL
6671 		&& check_snapshot_rec(sn->fr_child, fr->fr_child) == FAIL)
6672 	    || (sn->fr_win != NULL && !win_valid(sn->fr_win)))
6673 	return FAIL;
6674     return OK;
6675 }
6676 
6677 /*
6678  * Copy the size of snapshot frame "sn" to frame "fr".  Do the same for all
6679  * following frames and children.
6680  * Returns a pointer to the old current window, or NULL.
6681  */
6682     static win_T *
6683 restore_snapshot_rec(frame_T *sn, frame_T *fr)
6684 {
6685     win_T	*wp = NULL;
6686     win_T	*wp2;
6687 
6688     fr->fr_height = sn->fr_height;
6689     fr->fr_width = sn->fr_width;
6690     if (fr->fr_layout == FR_LEAF)
6691     {
6692 	frame_new_height(fr, fr->fr_height, FALSE, FALSE);
6693 	frame_new_width(fr, fr->fr_width, FALSE, FALSE);
6694 	wp = sn->fr_win;
6695     }
6696     if (sn->fr_next != NULL)
6697     {
6698 	wp2 = restore_snapshot_rec(sn->fr_next, fr->fr_next);
6699 	if (wp2 != NULL)
6700 	    wp = wp2;
6701     }
6702     if (sn->fr_child != NULL)
6703     {
6704 	wp2 = restore_snapshot_rec(sn->fr_child, fr->fr_child);
6705 	if (wp2 != NULL)
6706 	    wp = wp2;
6707     }
6708     return wp;
6709 }
6710 
6711 #if defined(FEAT_GUI) || defined(PROTO)
6712 /*
6713  * Return TRUE if there is any vertically split window.
6714  */
6715     int
6716 win_hasvertsplit(void)
6717 {
6718     frame_T	*fr;
6719 
6720     if (topframe->fr_layout == FR_ROW)
6721 	return TRUE;
6722 
6723     if (topframe->fr_layout == FR_COL)
6724 	FOR_ALL_FRAMES(fr, topframe->fr_child)
6725 	    if (fr->fr_layout == FR_ROW)
6726 		return TRUE;
6727 
6728     return FALSE;
6729 }
6730 #endif
6731 
6732 #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) || defined(PROTO)
6733     int
6734 get_win_number(win_T *wp, win_T *first_win)
6735 {
6736     int		i = 1;
6737     win_T	*w;
6738 
6739     for (w = first_win; w != NULL && w != wp; w = W_NEXT(w))
6740 	++i;
6741 
6742     if (w == NULL)
6743 	return 0;
6744     else
6745 	return i;
6746 }
6747 
6748     int
6749 get_tab_number(tabpage_T *tp UNUSED)
6750 {
6751     int		i = 1;
6752     tabpage_T	*t;
6753 
6754     for (t = first_tabpage; t != NULL && t != tp; t = t->tp_next)
6755 	++i;
6756 
6757     if (t == NULL)
6758 	return 0;
6759     else
6760 	return i;
6761 }
6762 #endif
6763 
6764 /*
6765  * Return TRUE if "topfrp" and its children are at the right height.
6766  */
6767     static int
6768 frame_check_height(frame_T *topfrp, int height)
6769 {
6770     frame_T *frp;
6771 
6772     if (topfrp->fr_height != height)
6773 	return FALSE;
6774 
6775     if (topfrp->fr_layout == FR_ROW)
6776 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
6777 	    if (frp->fr_height != height)
6778 		return FALSE;
6779 
6780     return TRUE;
6781 }
6782 
6783 /*
6784  * Return TRUE if "topfrp" and its children are at the right width.
6785  */
6786     static int
6787 frame_check_width(frame_T *topfrp, int width)
6788 {
6789     frame_T *frp;
6790 
6791     if (topfrp->fr_width != width)
6792 	return FALSE;
6793 
6794     if (topfrp->fr_layout == FR_COL)
6795 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
6796 	    if (frp->fr_width != width)
6797 		return FALSE;
6798 
6799     return TRUE;
6800 }
6801 
6802 #if defined(FEAT_SYN_HL) || defined(PROTO)
6803 /*
6804  * Simple int comparison function for use with qsort()
6805  */
6806     static int
6807 int_cmp(const void *a, const void *b)
6808 {
6809     return *(const int *)a - *(const int *)b;
6810 }
6811 
6812 /*
6813  * Handle setting 'colorcolumn' or 'textwidth' in window "wp".
6814  * Returns error message, NULL if it's OK.
6815  */
6816     char *
6817 check_colorcolumn(win_T *wp)
6818 {
6819     char_u	*s;
6820     int		col;
6821     int		count = 0;
6822     int		color_cols[256];
6823     int		i;
6824     int		j = 0;
6825 
6826     if (wp->w_buffer == NULL)
6827 	return NULL;  // buffer was closed
6828 
6829     for (s = wp->w_p_cc; *s != NUL && count < 255;)
6830     {
6831 	if (*s == '-' || *s == '+')
6832 	{
6833 	    // -N and +N: add to 'textwidth'
6834 	    col = (*s == '-') ? -1 : 1;
6835 	    ++s;
6836 	    if (!VIM_ISDIGIT(*s))
6837 		return e_invarg;
6838 	    col = col * getdigits(&s);
6839 	    if (wp->w_buffer->b_p_tw == 0)
6840 		goto skip;  // 'textwidth' not set, skip this item
6841 	    col += wp->w_buffer->b_p_tw;
6842 	    if (col < 0)
6843 		goto skip;
6844 	}
6845 	else if (VIM_ISDIGIT(*s))
6846 	    col = getdigits(&s);
6847 	else
6848 	    return e_invarg;
6849 	color_cols[count++] = col - 1;  // 1-based to 0-based
6850 skip:
6851 	if (*s == NUL)
6852 	    break;
6853 	if (*s != ',')
6854 	    return e_invarg;
6855 	if (*++s == NUL)
6856 	    return e_invarg;  // illegal trailing comma as in "set cc=80,"
6857     }
6858 
6859     vim_free(wp->w_p_cc_cols);
6860     if (count == 0)
6861 	wp->w_p_cc_cols = NULL;
6862     else
6863     {
6864 	wp->w_p_cc_cols = ALLOC_MULT(int, count + 1);
6865 	if (wp->w_p_cc_cols != NULL)
6866 	{
6867 	    // sort the columns for faster usage on screen redraw inside
6868 	    // win_line()
6869 	    qsort(color_cols, count, sizeof(int), int_cmp);
6870 
6871 	    for (i = 0; i < count; ++i)
6872 		// skip duplicates
6873 		if (j == 0 || wp->w_p_cc_cols[j - 1] != color_cols[i])
6874 		    wp->w_p_cc_cols[j++] = color_cols[i];
6875 	    wp->w_p_cc_cols[j] = -1;  // end marker
6876 	}
6877     }
6878 
6879     return NULL;  // no error
6880 }
6881 #endif
6882