xref: /vim-8.2.3635/src/window.c (revision cbcd9cbd)
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.cmod_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.cmod_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      // Both windows need redrawing.  Update all status lines, in case they
1277      // show something related to the window count or position.
1278     redraw_win_later(wp, NOT_VALID);
1279     redraw_win_later(oldwin, NOT_VALID);
1280     status_redraw_all();
1281 
1282     if (need_status)
1283     {
1284 	msg_row = Rows - 1;
1285 	msg_col = sc_col;
1286 	msg_clr_eos_force();	// Old command/ruler may still be there
1287 	comp_col();
1288 	msg_row = Rows - 1;
1289 	msg_col = 0;	// put position back at start of line
1290     }
1291 
1292     /*
1293      * equalize the window sizes.
1294      */
1295     if (do_equal || dir != 0)
1296 	win_equal(wp, TRUE,
1297 		(flags & WSP_VERT) ? (dir == 'v' ? 'b' : 'h')
1298 		: dir == 'h' ? 'b' : 'v');
1299 
1300     // Don't change the window height/width to 'winheight' / 'winwidth' if a
1301     // size was given.
1302     if (flags & WSP_VERT)
1303     {
1304 	i = p_wiw;
1305 	if (size != 0)
1306 	    p_wiw = size;
1307 
1308 # ifdef FEAT_GUI
1309 	// When 'guioptions' includes 'L' or 'R' may have to add scrollbars.
1310 	if (gui.in_use)
1311 	    gui_init_which_components(NULL);
1312 # endif
1313     }
1314     else
1315     {
1316 	i = p_wh;
1317 	if (size != 0)
1318 	    p_wh = size;
1319     }
1320 
1321 #ifdef FEAT_JUMPLIST
1322     // Keep same changelist position in new window.
1323     wp->w_changelistidx = oldwin->w_changelistidx;
1324 #endif
1325 
1326     /*
1327      * make the new window the current window
1328      */
1329     win_enter_ext(wp, FALSE, FALSE, TRUE, TRUE, TRUE);
1330     if (flags & WSP_VERT)
1331 	p_wiw = i;
1332     else
1333 	p_wh = i;
1334 
1335     return OK;
1336 }
1337 
1338 
1339 /*
1340  * Initialize window "newp" from window "oldp".
1341  * Used when splitting a window and when creating a new tab page.
1342  * The windows will both edit the same buffer.
1343  * WSP_NEWLOC may be specified in flags to prevent the location list from
1344  * being copied.
1345  */
1346     static void
1347 win_init(win_T *newp, win_T *oldp, int flags UNUSED)
1348 {
1349     int		i;
1350 
1351     newp->w_buffer = oldp->w_buffer;
1352 #ifdef FEAT_SYN_HL
1353     newp->w_s = &(oldp->w_buffer->b_s);
1354 #endif
1355     oldp->w_buffer->b_nwindows++;
1356     newp->w_cursor = oldp->w_cursor;
1357     newp->w_valid = 0;
1358     newp->w_curswant = oldp->w_curswant;
1359     newp->w_set_curswant = oldp->w_set_curswant;
1360     newp->w_topline = oldp->w_topline;
1361 #ifdef FEAT_DIFF
1362     newp->w_topfill = oldp->w_topfill;
1363 #endif
1364     newp->w_leftcol = oldp->w_leftcol;
1365     newp->w_pcmark = oldp->w_pcmark;
1366     newp->w_prev_pcmark = oldp->w_prev_pcmark;
1367     newp->w_alt_fnum = oldp->w_alt_fnum;
1368     newp->w_wrow = oldp->w_wrow;
1369     newp->w_fraction = oldp->w_fraction;
1370     newp->w_prev_fraction_row = oldp->w_prev_fraction_row;
1371 #ifdef FEAT_JUMPLIST
1372     copy_jumplist(oldp, newp);
1373 #endif
1374 #ifdef FEAT_QUICKFIX
1375     if (flags & WSP_NEWLOC)
1376     {
1377 	// Don't copy the location list.
1378 	newp->w_llist = NULL;
1379 	newp->w_llist_ref = NULL;
1380     }
1381     else
1382 	copy_loclist_stack(oldp, newp);
1383 #endif
1384     newp->w_localdir = (oldp->w_localdir == NULL)
1385 				    ? NULL : vim_strsave(oldp->w_localdir);
1386     newp->w_prevdir = (oldp->w_prevdir == NULL)
1387 				    ? NULL : vim_strsave(oldp->w_prevdir);
1388 
1389     // copy tagstack and folds
1390     for (i = 0; i < oldp->w_tagstacklen; i++)
1391     {
1392 	taggy_T	*tag = &newp->w_tagstack[i];
1393 	*tag = oldp->w_tagstack[i];
1394 	if (tag->tagname != NULL)
1395 	    tag->tagname = vim_strsave(tag->tagname);
1396 	if (tag->user_data != NULL)
1397 	    tag->user_data = vim_strsave(tag->user_data);
1398     }
1399     newp->w_tagstackidx = oldp->w_tagstackidx;
1400     newp->w_tagstacklen = oldp->w_tagstacklen;
1401 #ifdef FEAT_FOLDING
1402     copyFoldingState(oldp, newp);
1403 #endif
1404 
1405     win_init_some(newp, oldp);
1406 
1407 #ifdef FEAT_SYN_HL
1408     check_colorcolumn(newp);
1409 #endif
1410 }
1411 
1412 /*
1413  * Initialize window "newp" from window "old".
1414  * Only the essential things are copied.
1415  */
1416     static void
1417 win_init_some(win_T *newp, win_T *oldp)
1418 {
1419     // Use the same argument list.
1420     newp->w_alist = oldp->w_alist;
1421     ++newp->w_alist->al_refcount;
1422     newp->w_arg_idx = oldp->w_arg_idx;
1423 
1424     // copy options from existing window
1425     win_copy_options(oldp, newp);
1426 }
1427 
1428 /*
1429  * Return TRUE if "win" is a global popup or a popup in the current tab page.
1430  */
1431     int
1432 win_valid_popup(win_T *win UNUSED)
1433 {
1434 #ifdef FEAT_PROP_POPUP
1435     win_T	*wp;
1436 
1437     FOR_ALL_POPUPWINS(wp)
1438 	if (wp == win)
1439 	    return TRUE;
1440     FOR_ALL_POPUPWINS_IN_TAB(curtab, wp)
1441 	if (wp == win)
1442 	    return TRUE;
1443 #endif
1444     return FALSE;
1445 }
1446 
1447 /*
1448  * Check if "win" is a pointer to an existing window in the current tab page.
1449  */
1450     int
1451 win_valid(win_T *win)
1452 {
1453     win_T	*wp;
1454 
1455     if (win == NULL)
1456 	return FALSE;
1457     FOR_ALL_WINDOWS(wp)
1458 	if (wp == win)
1459 	    return TRUE;
1460     return win_valid_popup(win);
1461 }
1462 
1463 /*
1464  * Find window "id" in the current tab page.
1465  * Return NULL if not found.
1466  */
1467     win_T *
1468 win_find_by_id(int id)
1469 {
1470     win_T   *wp;
1471 
1472     FOR_ALL_WINDOWS(wp)
1473 	if (wp->w_id == id)
1474 	    return wp;
1475     return NULL;
1476 }
1477 
1478 /*
1479  * Check if "win" is a pointer to an existing window in any tab page.
1480  */
1481     int
1482 win_valid_any_tab(win_T *win)
1483 {
1484     win_T	*wp;
1485     tabpage_T	*tp;
1486 
1487     if (win == NULL)
1488 	return FALSE;
1489     FOR_ALL_TABPAGES(tp)
1490     {
1491 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
1492 	{
1493 	    if (wp == win)
1494 		return TRUE;
1495 	}
1496 #ifdef FEAT_PROP_POPUP
1497 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
1498 	    if (wp == win)
1499 		return TRUE;
1500 #endif
1501     }
1502     return win_valid_popup(win);
1503 }
1504 
1505 /*
1506  * Return the number of windows.
1507  */
1508     int
1509 win_count(void)
1510 {
1511     win_T	*wp;
1512     int		count = 0;
1513 
1514     FOR_ALL_WINDOWS(wp)
1515 	++count;
1516     return count;
1517 }
1518 
1519 /*
1520  * Make "count" windows on the screen.
1521  * Return actual number of windows on the screen.
1522  * Must be called when there is just one window, filling the whole screen
1523  * (excluding the command line).
1524  */
1525     int
1526 make_windows(
1527     int		count,
1528     int		vertical UNUSED)  // split windows vertically if TRUE
1529 {
1530     int		maxcount;
1531     int		todo;
1532 
1533     if (vertical)
1534     {
1535 	// Each windows needs at least 'winminwidth' lines and a separator
1536 	// column.
1537 	maxcount = (curwin->w_width + curwin->w_vsep_width
1538 					     - (p_wiw - p_wmw)) / (p_wmw + 1);
1539     }
1540     else
1541     {
1542 	// Each window needs at least 'winminheight' lines and a status line.
1543 	maxcount = (VISIBLE_HEIGHT(curwin) + curwin->w_status_height
1544 				  - (p_wh - p_wmh)) / (p_wmh + STATUS_HEIGHT);
1545     }
1546 
1547     if (maxcount < 2)
1548 	maxcount = 2;
1549     if (count > maxcount)
1550 	count = maxcount;
1551 
1552     /*
1553      * add status line now, otherwise first window will be too big
1554      */
1555     if (count > 1)
1556 	last_status(TRUE);
1557 
1558     /*
1559      * Don't execute autocommands while creating the windows.  Must do that
1560      * when putting the buffers in the windows.
1561      */
1562     block_autocmds();
1563 
1564     // todo is number of windows left to create
1565     for (todo = count - 1; todo > 0; --todo)
1566 	if (vertical)
1567 	{
1568 	    if (win_split(curwin->w_width - (curwin->w_width - todo)
1569 			/ (todo + 1) - 1, WSP_VERT | WSP_ABOVE) == FAIL)
1570 		break;
1571 	}
1572 	else
1573 	{
1574 	    if (win_split(curwin->w_height - (curwin->w_height - todo
1575 			    * STATUS_HEIGHT) / (todo + 1)
1576 			- STATUS_HEIGHT, WSP_ABOVE) == FAIL)
1577 		break;
1578 	}
1579 
1580     unblock_autocmds();
1581 
1582     // return actual number of windows
1583     return (count - todo);
1584 }
1585 
1586 /*
1587  * Exchange current and next window
1588  */
1589     static void
1590 win_exchange(long Prenum)
1591 {
1592     frame_T	*frp;
1593     frame_T	*frp2;
1594     win_T	*wp;
1595     win_T	*wp2;
1596     int		temp;
1597 
1598     if (ERROR_IF_ANY_POPUP_WINDOW)
1599 	return;
1600     if (ONE_WINDOW)	    // just one window
1601     {
1602 	beep_flush();
1603 	return;
1604     }
1605 
1606 #ifdef FEAT_GUI
1607     need_mouse_correct = TRUE;
1608 #endif
1609 
1610     /*
1611      * find window to exchange with
1612      */
1613     if (Prenum)
1614     {
1615 	frp = curwin->w_frame->fr_parent->fr_child;
1616 	while (frp != NULL && --Prenum > 0)
1617 	    frp = frp->fr_next;
1618     }
1619     else if (curwin->w_frame->fr_next != NULL)	// Swap with next
1620 	frp = curwin->w_frame->fr_next;
1621     else    // Swap last window in row/col with previous
1622 	frp = curwin->w_frame->fr_prev;
1623 
1624     // We can only exchange a window with another window, not with a frame
1625     // containing windows.
1626     if (frp == NULL || frp->fr_win == NULL || frp->fr_win == curwin)
1627 	return;
1628     wp = frp->fr_win;
1629 
1630 /*
1631  * 1. remove curwin from the list. Remember after which window it was in wp2
1632  * 2. insert curwin before wp in the list
1633  * if wp != wp2
1634  *    3. remove wp from the list
1635  *    4. insert wp after wp2
1636  * 5. exchange the status line height and vsep width.
1637  */
1638     wp2 = curwin->w_prev;
1639     frp2 = curwin->w_frame->fr_prev;
1640     if (wp->w_prev != curwin)
1641     {
1642 	win_remove(curwin, NULL);
1643 	frame_remove(curwin->w_frame);
1644 	win_append(wp->w_prev, curwin);
1645 	frame_insert(frp, curwin->w_frame);
1646     }
1647     if (wp != wp2)
1648     {
1649 	win_remove(wp, NULL);
1650 	frame_remove(wp->w_frame);
1651 	win_append(wp2, wp);
1652 	if (frp2 == NULL)
1653 	    frame_insert(wp->w_frame->fr_parent->fr_child, wp->w_frame);
1654 	else
1655 	    frame_append(frp2, wp->w_frame);
1656     }
1657     temp = curwin->w_status_height;
1658     curwin->w_status_height = wp->w_status_height;
1659     wp->w_status_height = temp;
1660     temp = curwin->w_vsep_width;
1661     curwin->w_vsep_width = wp->w_vsep_width;
1662     wp->w_vsep_width = temp;
1663 
1664     // If the windows are not in the same frame, exchange the sizes to avoid
1665     // messing up the window layout.  Otherwise fix the frame sizes.
1666     if (curwin->w_frame->fr_parent != wp->w_frame->fr_parent)
1667     {
1668 	temp = curwin->w_height;
1669 	curwin->w_height = wp->w_height;
1670 	wp->w_height = temp;
1671 	temp = curwin->w_width;
1672 	curwin->w_width = wp->w_width;
1673 	wp->w_width = temp;
1674     }
1675     else
1676     {
1677 	frame_fix_height(curwin);
1678 	frame_fix_height(wp);
1679 	frame_fix_width(curwin);
1680 	frame_fix_width(wp);
1681     }
1682 
1683     (void)win_comp_pos();		// recompute window positions
1684 
1685     win_enter(wp, TRUE);
1686     redraw_all_later(NOT_VALID);
1687 }
1688 
1689 /*
1690  * rotate windows: if upwards TRUE the second window becomes the first one
1691  *		   if upwards FALSE the first window becomes the second one
1692  */
1693     static void
1694 win_rotate(int upwards, int count)
1695 {
1696     win_T	*wp1;
1697     win_T	*wp2;
1698     frame_T	*frp;
1699     int		n;
1700 
1701     if (ONE_WINDOW)		// nothing to do
1702     {
1703 	beep_flush();
1704 	return;
1705     }
1706 
1707 #ifdef FEAT_GUI
1708     need_mouse_correct = TRUE;
1709 #endif
1710 
1711     // Check if all frames in this row/col have one window.
1712     FOR_ALL_FRAMES(frp, curwin->w_frame->fr_parent->fr_child)
1713 	if (frp->fr_win == NULL)
1714 	{
1715 	    emsg(_("E443: Cannot rotate when another window is split"));
1716 	    return;
1717 	}
1718 
1719     while (count--)
1720     {
1721 	if (upwards)		// first window becomes last window
1722 	{
1723 	    // remove first window/frame from the list
1724 	    frp = curwin->w_frame->fr_parent->fr_child;
1725 	    wp1 = frp->fr_win;
1726 	    win_remove(wp1, NULL);
1727 	    frame_remove(frp);
1728 
1729 	    // find last frame and append removed window/frame after it
1730 	    for ( ; frp->fr_next != NULL; frp = frp->fr_next)
1731 		;
1732 	    win_append(frp->fr_win, wp1);
1733 	    frame_append(frp, wp1->w_frame);
1734 
1735 	    wp2 = frp->fr_win;		// previously last window
1736 	}
1737 	else			// last window becomes first window
1738 	{
1739 	    // find last window/frame in the list and remove it
1740 	    for (frp = curwin->w_frame; frp->fr_next != NULL;
1741 							   frp = frp->fr_next)
1742 		;
1743 	    wp1 = frp->fr_win;
1744 	    wp2 = wp1->w_prev;		    // will become last window
1745 	    win_remove(wp1, NULL);
1746 	    frame_remove(frp);
1747 
1748 	    // append the removed window/frame before the first in the list
1749 	    win_append(frp->fr_parent->fr_child->fr_win->w_prev, wp1);
1750 	    frame_insert(frp->fr_parent->fr_child, frp);
1751 	}
1752 
1753 	// exchange status height and vsep width of old and new last window
1754 	n = wp2->w_status_height;
1755 	wp2->w_status_height = wp1->w_status_height;
1756 	wp1->w_status_height = n;
1757 	frame_fix_height(wp1);
1758 	frame_fix_height(wp2);
1759 	n = wp2->w_vsep_width;
1760 	wp2->w_vsep_width = wp1->w_vsep_width;
1761 	wp1->w_vsep_width = n;
1762 	frame_fix_width(wp1);
1763 	frame_fix_width(wp2);
1764 
1765 	// recompute w_winrow and w_wincol for all windows
1766 	(void)win_comp_pos();
1767     }
1768 
1769     redraw_all_later(NOT_VALID);
1770 }
1771 
1772 /*
1773  * Move the current window to the very top/bottom/left/right of the screen.
1774  */
1775     static void
1776 win_totop(int size, int flags)
1777 {
1778     int		dir;
1779     int		height = curwin->w_height;
1780 
1781     if (ONE_WINDOW)
1782     {
1783 	beep_flush();
1784 	return;
1785     }
1786     if (check_split_disallowed() == FAIL)
1787 	return;
1788 
1789     // Remove the window and frame from the tree of frames.
1790     (void)winframe_remove(curwin, &dir, NULL);
1791     win_remove(curwin, NULL);
1792     last_status(FALSE);	    // may need to remove last status line
1793     (void)win_comp_pos();   // recompute window positions
1794 
1795     // Split a window on the desired side and put the window there.
1796     (void)win_split_ins(size, flags, curwin, dir);
1797     if (!(flags & WSP_VERT))
1798     {
1799 	win_setheight(height);
1800 	if (p_ea)
1801 	    win_equal(curwin, TRUE, 'v');
1802     }
1803 
1804 #if defined(FEAT_GUI)
1805     // When 'guioptions' includes 'L' or 'R' may have to remove or add
1806     // scrollbars.  Have to update them anyway.
1807     gui_may_update_scrollbars();
1808 #endif
1809 }
1810 
1811 /*
1812  * Move window "win1" to below/right of "win2" and make "win1" the current
1813  * window.  Only works within the same frame!
1814  */
1815     void
1816 win_move_after(win_T *win1, win_T *win2)
1817 {
1818     int		height;
1819 
1820     // check if the arguments are reasonable
1821     if (win1 == win2)
1822 	return;
1823 
1824     // check if there is something to do
1825     if (win2->w_next != win1)
1826     {
1827 	if (win1->w_frame->fr_parent != win2->w_frame->fr_parent)
1828 	{
1829 	    iemsg("INTERNAL: trying to move a window into another frame");
1830 	    return;
1831 	}
1832 
1833 	// may need to move the status line/vertical separator of the last
1834 	// window
1835 	if (win1 == lastwin)
1836 	{
1837 	    height = win1->w_prev->w_status_height;
1838 	    win1->w_prev->w_status_height = win1->w_status_height;
1839 	    win1->w_status_height = height;
1840 	    if (win1->w_prev->w_vsep_width == 1)
1841 	    {
1842 		// Remove the vertical separator from the last-but-one window,
1843 		// add it to the last window.  Adjust the frame widths.
1844 		win1->w_prev->w_vsep_width = 0;
1845 		win1->w_prev->w_frame->fr_width -= 1;
1846 		win1->w_vsep_width = 1;
1847 		win1->w_frame->fr_width += 1;
1848 	    }
1849 	}
1850 	else if (win2 == lastwin)
1851 	{
1852 	    height = win1->w_status_height;
1853 	    win1->w_status_height = win2->w_status_height;
1854 	    win2->w_status_height = height;
1855 	    if (win1->w_vsep_width == 1)
1856 	    {
1857 		// Remove the vertical separator from win1, add it to the last
1858 		// window, win2.  Adjust the frame widths.
1859 		win2->w_vsep_width = 1;
1860 		win2->w_frame->fr_width += 1;
1861 		win1->w_vsep_width = 0;
1862 		win1->w_frame->fr_width -= 1;
1863 	    }
1864 	}
1865 	win_remove(win1, NULL);
1866 	frame_remove(win1->w_frame);
1867 	win_append(win2, win1);
1868 	frame_append(win2->w_frame, win1->w_frame);
1869 
1870 	(void)win_comp_pos();	// recompute w_winrow for all windows
1871 	redraw_later(NOT_VALID);
1872     }
1873     win_enter(win1, FALSE);
1874 }
1875 
1876 /*
1877  * Make all windows the same height.
1878  * 'next_curwin' will soon be the current window, make sure it has enough
1879  * rows.
1880  */
1881     void
1882 win_equal(
1883     win_T	*next_curwin,	// pointer to current window to be or NULL
1884     int		current,	// do only frame with current window
1885     int		dir)		// 'v' for vertically, 'h' for horizontally,
1886 				// 'b' for both, 0 for using p_ead
1887 {
1888     if (dir == 0)
1889 	dir = *p_ead;
1890     win_equal_rec(next_curwin == NULL ? curwin : next_curwin, current,
1891 		      topframe, dir, 0, tabline_height(),
1892 					   (int)Columns, topframe->fr_height);
1893 }
1894 
1895 /*
1896  * Set a frame to a new position and height, spreading the available room
1897  * equally over contained frames.
1898  * The window "next_curwin" (if not NULL) should at least get the size from
1899  * 'winheight' and 'winwidth' if possible.
1900  */
1901     static void
1902 win_equal_rec(
1903     win_T	*next_curwin,	// pointer to current window to be or NULL
1904     int		current,	// do only frame with current window
1905     frame_T	*topfr,		// frame to set size off
1906     int		dir,		// 'v', 'h' or 'b', see win_equal()
1907     int		col,		// horizontal position for frame
1908     int		row,		// vertical position for frame
1909     int		width,		// new width of frame
1910     int		height)		// new height of frame
1911 {
1912     int		n, m;
1913     int		extra_sep = 0;
1914     int		wincount, totwincount = 0;
1915     frame_T	*fr;
1916     int		next_curwin_size = 0;
1917     int		room = 0;
1918     int		new_size;
1919     int		has_next_curwin = 0;
1920     int		hnc;
1921 
1922     if (topfr->fr_layout == FR_LEAF)
1923     {
1924 	// Set the width/height of this frame.
1925 	// Redraw when size or position changes
1926 	if (topfr->fr_height != height || topfr->fr_win->w_winrow != row
1927 		|| topfr->fr_width != width || topfr->fr_win->w_wincol != col
1928 	   )
1929 	{
1930 	    topfr->fr_win->w_winrow = row;
1931 	    frame_new_height(topfr, height, FALSE, FALSE);
1932 	    topfr->fr_win->w_wincol = col;
1933 	    frame_new_width(topfr, width, FALSE, FALSE);
1934 	    redraw_all_later(NOT_VALID);
1935 	}
1936     }
1937     else if (topfr->fr_layout == FR_ROW)
1938     {
1939 	topfr->fr_width = width;
1940 	topfr->fr_height = height;
1941 
1942 	if (dir != 'v')			// equalize frame widths
1943 	{
1944 	    // Compute the maximum number of windows horizontally in this
1945 	    // frame.
1946 	    n = frame_minwidth(topfr, NOWIN);
1947 	    // add one for the rightmost window, it doesn't have a separator
1948 	    if (col + width == Columns)
1949 		extra_sep = 1;
1950 	    else
1951 		extra_sep = 0;
1952 	    totwincount = (n + extra_sep) / (p_wmw + 1);
1953 	    has_next_curwin = frame_has_win(topfr, next_curwin);
1954 
1955 	    /*
1956 	     * Compute width for "next_curwin" window and room available for
1957 	     * other windows.
1958 	     * "m" is the minimal width when counting p_wiw for "next_curwin".
1959 	     */
1960 	    m = frame_minwidth(topfr, next_curwin);
1961 	    room = width - m;
1962 	    if (room < 0)
1963 	    {
1964 		next_curwin_size = p_wiw + room;
1965 		room = 0;
1966 	    }
1967 	    else
1968 	    {
1969 		next_curwin_size = -1;
1970 		FOR_ALL_FRAMES(fr, topfr->fr_child)
1971 		{
1972 		    // If 'winfixwidth' set keep the window width if
1973 		    // possible.
1974 		    // Watch out for this window being the next_curwin.
1975 		    if (frame_fixed_width(fr))
1976 		    {
1977 			n = frame_minwidth(fr, NOWIN);
1978 			new_size = fr->fr_width;
1979 			if (frame_has_win(fr, next_curwin))
1980 			{
1981 			    room += p_wiw - p_wmw;
1982 			    next_curwin_size = 0;
1983 			    if (new_size < p_wiw)
1984 				new_size = p_wiw;
1985 			}
1986 			else
1987 			    // These windows don't use up room.
1988 			    totwincount -= (n + (fr->fr_next == NULL
1989 					      ? extra_sep : 0)) / (p_wmw + 1);
1990 			room -= new_size - n;
1991 			if (room < 0)
1992 			{
1993 			    new_size += room;
1994 			    room = 0;
1995 			}
1996 			fr->fr_newwidth = new_size;
1997 		    }
1998 		}
1999 		if (next_curwin_size == -1)
2000 		{
2001 		    if (!has_next_curwin)
2002 			next_curwin_size = 0;
2003 		    else if (totwincount > 1
2004 			    && (room + (totwincount - 2))
2005 						  / (totwincount - 1) > p_wiw)
2006 		    {
2007 			// Can make all windows wider than 'winwidth', spread
2008 			// the room equally.
2009 			next_curwin_size = (room + p_wiw
2010 					    + (totwincount - 1) * p_wmw
2011 					    + (totwincount - 1)) / totwincount;
2012 			room -= next_curwin_size - p_wiw;
2013 		    }
2014 		    else
2015 			next_curwin_size = p_wiw;
2016 		}
2017 	    }
2018 
2019 	    if (has_next_curwin)
2020 		--totwincount;		// don't count curwin
2021 	}
2022 
2023 	FOR_ALL_FRAMES(fr, topfr->fr_child)
2024 	{
2025 	    wincount = 1;
2026 	    if (fr->fr_next == NULL)
2027 		// last frame gets all that remains (avoid roundoff error)
2028 		new_size = width;
2029 	    else if (dir == 'v')
2030 		new_size = fr->fr_width;
2031 	    else if (frame_fixed_width(fr))
2032 	    {
2033 		new_size = fr->fr_newwidth;
2034 		wincount = 0;	    // doesn't count as a sizeable window
2035 	    }
2036 	    else
2037 	    {
2038 		// Compute the maximum number of windows horiz. in "fr".
2039 		n = frame_minwidth(fr, NOWIN);
2040 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2041 								/ (p_wmw + 1);
2042 		m = frame_minwidth(fr, next_curwin);
2043 		if (has_next_curwin)
2044 		    hnc = frame_has_win(fr, next_curwin);
2045 		else
2046 		    hnc = FALSE;
2047 		if (hnc)	    // don't count next_curwin
2048 		    --wincount;
2049 		if (totwincount == 0)
2050 		    new_size = room;
2051 		else
2052 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2053 								/ totwincount;
2054 		if (hnc)	    // add next_curwin size
2055 		{
2056 		    next_curwin_size -= p_wiw - (m - n);
2057 		    new_size += next_curwin_size;
2058 		    room -= new_size - next_curwin_size;
2059 		}
2060 		else
2061 		    room -= new_size;
2062 		new_size += n;
2063 	    }
2064 
2065 	    // Skip frame that is full width when splitting or closing a
2066 	    // window, unless equalizing all frames.
2067 	    if (!current || dir != 'v' || topfr->fr_parent != NULL
2068 		    || (new_size != fr->fr_width)
2069 		    || frame_has_win(fr, next_curwin))
2070 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2071 							    new_size, height);
2072 	    col += new_size;
2073 	    width -= new_size;
2074 	    totwincount -= wincount;
2075 	}
2076     }
2077     else // topfr->fr_layout == FR_COL
2078     {
2079 	topfr->fr_width = width;
2080 	topfr->fr_height = height;
2081 
2082 	if (dir != 'h')			// equalize frame heights
2083 	{
2084 	    // Compute maximum number of windows vertically in this frame.
2085 	    n = frame_minheight(topfr, NOWIN);
2086 	    // add one for the bottom window if it doesn't have a statusline
2087 	    if (row + height == cmdline_row && p_ls == 0)
2088 		extra_sep = 1;
2089 	    else
2090 		extra_sep = 0;
2091 	    totwincount = (n + extra_sep) / (p_wmh + 1);
2092 	    has_next_curwin = frame_has_win(topfr, next_curwin);
2093 
2094 	    /*
2095 	     * Compute height for "next_curwin" window and room available for
2096 	     * other windows.
2097 	     * "m" is the minimal height when counting p_wh for "next_curwin".
2098 	     */
2099 	    m = frame_minheight(topfr, next_curwin);
2100 	    room = height - m;
2101 	    if (room < 0)
2102 	    {
2103 		// The room is less then 'winheight', use all space for the
2104 		// current window.
2105 		next_curwin_size = p_wh + room;
2106 		room = 0;
2107 	    }
2108 	    else
2109 	    {
2110 		next_curwin_size = -1;
2111 		FOR_ALL_FRAMES(fr, topfr->fr_child)
2112 		{
2113 		    // If 'winfixheight' set keep the window height if
2114 		    // possible.
2115 		    // Watch out for this window being the next_curwin.
2116 		    if (frame_fixed_height(fr))
2117 		    {
2118 			n = frame_minheight(fr, NOWIN);
2119 			new_size = fr->fr_height;
2120 			if (frame_has_win(fr, next_curwin))
2121 			{
2122 			    room += p_wh - p_wmh;
2123 			    next_curwin_size = 0;
2124 			    if (new_size < p_wh)
2125 				new_size = p_wh;
2126 			}
2127 			else
2128 			    // These windows don't use up room.
2129 			    totwincount -= (n + (fr->fr_next == NULL
2130 					      ? extra_sep : 0)) / (p_wmh + 1);
2131 			room -= new_size - n;
2132 			if (room < 0)
2133 			{
2134 			    new_size += room;
2135 			    room = 0;
2136 			}
2137 			fr->fr_newheight = new_size;
2138 		    }
2139 		}
2140 		if (next_curwin_size == -1)
2141 		{
2142 		    if (!has_next_curwin)
2143 			next_curwin_size = 0;
2144 		    else if (totwincount > 1
2145 			    && (room + (totwincount - 2))
2146 						   / (totwincount - 1) > p_wh)
2147 		    {
2148 			// can make all windows higher than 'winheight',
2149 			// spread the room equally.
2150 			next_curwin_size = (room + p_wh
2151 					   + (totwincount - 1) * p_wmh
2152 					   + (totwincount - 1)) / totwincount;
2153 			room -= next_curwin_size - p_wh;
2154 		    }
2155 		    else
2156 			next_curwin_size = p_wh;
2157 		}
2158 	    }
2159 
2160 	    if (has_next_curwin)
2161 		--totwincount;		// don't count curwin
2162 	}
2163 
2164 	FOR_ALL_FRAMES(fr, topfr->fr_child)
2165 	{
2166 	    wincount = 1;
2167 	    if (fr->fr_next == NULL)
2168 		// last frame gets all that remains (avoid roundoff error)
2169 		new_size = height;
2170 	    else if (dir == 'h')
2171 		new_size = fr->fr_height;
2172 	    else if (frame_fixed_height(fr))
2173 	    {
2174 		new_size = fr->fr_newheight;
2175 		wincount = 0;	    // doesn't count as a sizeable window
2176 	    }
2177 	    else
2178 	    {
2179 		// Compute the maximum number of windows vert. in "fr".
2180 		n = frame_minheight(fr, NOWIN);
2181 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2182 								/ (p_wmh + 1);
2183 		m = frame_minheight(fr, next_curwin);
2184 		if (has_next_curwin)
2185 		    hnc = frame_has_win(fr, next_curwin);
2186 		else
2187 		    hnc = FALSE;
2188 		if (hnc)	    // don't count next_curwin
2189 		    --wincount;
2190 		if (totwincount == 0)
2191 		    new_size = room;
2192 		else
2193 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2194 								/ totwincount;
2195 		if (hnc)	    // add next_curwin size
2196 		{
2197 		    next_curwin_size -= p_wh - (m - n);
2198 		    new_size += next_curwin_size;
2199 		    room -= new_size - next_curwin_size;
2200 		}
2201 		else
2202 		    room -= new_size;
2203 		new_size += n;
2204 	    }
2205 	    // Skip frame that is full width when splitting or closing a
2206 	    // window, unless equalizing all frames.
2207 	    if (!current || dir != 'h' || topfr->fr_parent != NULL
2208 		    || (new_size != fr->fr_height)
2209 		    || frame_has_win(fr, next_curwin))
2210 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2211 							     width, new_size);
2212 	    row += new_size;
2213 	    height -= new_size;
2214 	    totwincount -= wincount;
2215 	}
2216     }
2217 }
2218 
2219 #ifdef FEAT_JOB_CHANNEL
2220     static void
2221 leaving_window(win_T *win)
2222 {
2223     // Only matters for a prompt window.
2224     if (!bt_prompt(win->w_buffer))
2225 	return;
2226 
2227     // When leaving a prompt window stop Insert mode and perhaps restart
2228     // it when entering that window again.
2229     win->w_buffer->b_prompt_insert = restart_edit;
2230     if (restart_edit != 0 && mode_displayed)
2231 	clear_cmdline = TRUE;		// unshow mode later
2232     restart_edit = NUL;
2233 
2234     // When leaving the window (or closing the window) was done from a
2235     // callback we need to break out of the Insert mode loop and restart Insert
2236     // mode when entering the window again.
2237     if (State & INSERT)
2238     {
2239 	stop_insert_mode = TRUE;
2240 	if (win->w_buffer->b_prompt_insert == NUL)
2241 	    win->w_buffer->b_prompt_insert = 'A';
2242     }
2243 }
2244 
2245     void
2246 entering_window(win_T *win)
2247 {
2248     // Only matters for a prompt window.
2249     if (!bt_prompt(win->w_buffer))
2250 	return;
2251 
2252     // When switching to a prompt buffer that was in Insert mode, don't stop
2253     // Insert mode, it may have been set in leaving_window().
2254     if (win->w_buffer->b_prompt_insert != NUL)
2255 	stop_insert_mode = FALSE;
2256 
2257     // When entering the prompt window restart Insert mode if we were in Insert
2258     // mode when we left it.
2259     restart_edit = win->w_buffer->b_prompt_insert;
2260 }
2261 #endif
2262 
2263 /*
2264  * Close all windows for buffer "buf".
2265  */
2266     void
2267 close_windows(
2268     buf_T	*buf,
2269     int		keep_curwin)	    // don't close "curwin"
2270 {
2271     win_T	*wp;
2272     tabpage_T   *tp, *nexttp;
2273     int		h = tabline_height();
2274     int		count = tabpage_index(NULL);
2275 
2276     ++RedrawingDisabled;
2277 
2278     for (wp = firstwin; wp != NULL && !ONE_WINDOW; )
2279     {
2280 	if (wp->w_buffer == buf && (!keep_curwin || wp != curwin)
2281 		&& !(wp->w_closing || wp->w_buffer->b_locked > 0))
2282 	{
2283 	    if (win_close(wp, FALSE) == FAIL)
2284 		// If closing the window fails give up, to avoid looping
2285 		// forever.
2286 		break;
2287 
2288 	    // Start all over, autocommands may change the window layout.
2289 	    wp = firstwin;
2290 	}
2291 	else
2292 	    wp = wp->w_next;
2293     }
2294 
2295     // Also check windows in other tab pages.
2296     for (tp = first_tabpage; tp != NULL; tp = nexttp)
2297     {
2298 	nexttp = tp->tp_next;
2299 	if (tp != curtab)
2300 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
2301 		if (wp->w_buffer == buf
2302 		    && !(wp->w_closing || wp->w_buffer->b_locked > 0))
2303 		{
2304 		    win_close_othertab(wp, FALSE, tp);
2305 
2306 		    // Start all over, the tab page may be closed and
2307 		    // autocommands may change the window layout.
2308 		    nexttp = first_tabpage;
2309 		    break;
2310 		}
2311     }
2312 
2313     --RedrawingDisabled;
2314 
2315     if (count != tabpage_index(NULL))
2316 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2317 
2318     redraw_tabline = TRUE;
2319     if (h != tabline_height())
2320 	shell_new_rows();
2321 }
2322 
2323 /*
2324  * Return TRUE if the current window is the only window that exists (ignoring
2325  * "aucmd_win").
2326  * Returns FALSE if there is a window, possibly in another tab page.
2327  */
2328     static int
2329 last_window(void)
2330 {
2331     return (one_window() && first_tabpage->tp_next == NULL);
2332 }
2333 
2334 /*
2335  * Return TRUE if there is only one window other than "aucmd_win" in the
2336  * current tab page.
2337  */
2338     int
2339 one_window(void)
2340 {
2341     win_T	*wp;
2342     int		seen_one = FALSE;
2343 
2344     FOR_ALL_WINDOWS(wp)
2345     {
2346 	if (wp != aucmd_win)
2347 	{
2348 	    if (seen_one)
2349 		return FALSE;
2350 	    seen_one = TRUE;
2351 	}
2352     }
2353     return TRUE;
2354 }
2355 
2356 /*
2357  * Close the possibly last window in a tab page.
2358  * Returns TRUE when the window was closed already.
2359  */
2360     static int
2361 close_last_window_tabpage(
2362     win_T	*win,
2363     int		free_buf,
2364     tabpage_T   *prev_curtab)
2365 {
2366     if (ONE_WINDOW)
2367     {
2368 	buf_T	*old_curbuf = curbuf;
2369 
2370 	/*
2371 	 * Closing the last window in a tab page.  First go to another tab
2372 	 * page and then close the window and the tab page.  This avoids that
2373 	 * curwin and curtab are invalid while we are freeing memory, they may
2374 	 * be used in GUI events.
2375 	 * Don't trigger autocommands yet, they may use wrong values, so do
2376 	 * that below.
2377 	 */
2378 	goto_tabpage_tp(alt_tabpage(), FALSE, TRUE);
2379 	redraw_tabline = TRUE;
2380 
2381 	// Safety check: Autocommands may have closed the window when jumping
2382 	// to the other tab page.
2383 	if (valid_tabpage(prev_curtab) && prev_curtab->tp_firstwin == win)
2384 	{
2385 	    int	    h = tabline_height();
2386 
2387 	    win_close_othertab(win, free_buf, prev_curtab);
2388 	    if (h != tabline_height())
2389 		shell_new_rows();
2390 	}
2391 #ifdef FEAT_JOB_CHANNEL
2392 	entering_window(curwin);
2393 #endif
2394 	// Since goto_tabpage_tp above did not trigger *Enter autocommands, do
2395 	// that now.
2396 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2397 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
2398 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
2399 	if (old_curbuf != curbuf)
2400 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2401 	return TRUE;
2402     }
2403     return FALSE;
2404 }
2405 
2406 /*
2407  * Close the buffer of "win" and unload it if "action" is DOBUF_UNLOAD.
2408  * "action" can also be zero (do nothing) or DOBUF_WIPE.
2409  * "abort_if_last" is passed to close_buffer(): abort closing if all other
2410  * windows are closed.
2411  */
2412     static void
2413 win_close_buffer(win_T *win, int action, int abort_if_last)
2414 {
2415 #ifdef FEAT_SYN_HL
2416     // Free independent synblock before the buffer is freed.
2417     if (win->w_buffer != NULL)
2418 	reset_synblock(win);
2419 #endif
2420 
2421 #ifdef FEAT_QUICKFIX
2422     // When the quickfix/location list window is closed, unlist the buffer.
2423     if (win->w_buffer != NULL && bt_quickfix(win->w_buffer))
2424 	win->w_buffer->b_p_bl = FALSE;
2425 #endif
2426 
2427     // Close the link to the buffer.
2428     if (win->w_buffer != NULL)
2429     {
2430 	bufref_T    bufref;
2431 
2432 	set_bufref(&bufref, curbuf);
2433 	win->w_closing = TRUE;
2434 	close_buffer(win, win->w_buffer, action, abort_if_last, FALSE);
2435 	if (win_valid_any_tab(win))
2436 	    win->w_closing = FALSE;
2437 	// Make sure curbuf is valid. It can become invalid if 'bufhidden' is
2438 	// "wipe".
2439 	if (!bufref_valid(&bufref))
2440 	    curbuf = firstbuf;
2441     }
2442 }
2443 
2444 /*
2445  * Close window "win".  Only works for the current tab page.
2446  * If "free_buf" is TRUE related buffer may be unloaded.
2447  *
2448  * Called by :quit, :close, :xit, :wq and findtag().
2449  * Returns FAIL when the window was not closed.
2450  */
2451     int
2452 win_close(win_T *win, int free_buf)
2453 {
2454     win_T	*wp;
2455     int		other_buffer = FALSE;
2456     int		close_curwin = FALSE;
2457     int		dir;
2458     int		help_window = FALSE;
2459     tabpage_T   *prev_curtab = curtab;
2460     frame_T	*win_frame = win->w_frame->fr_parent;
2461 #ifdef FEAT_DIFF
2462     int		had_diffmode = win->w_p_diff;
2463 #endif
2464 
2465 #if defined(FEAT_TERMINAL) && defined(FEAT_PROP_POPUP)
2466     // Can close a popup window with a terminal if the job has finished.
2467     if (may_close_term_popup() == OK)
2468 	return OK;
2469 #endif
2470     if (ERROR_IF_ANY_POPUP_WINDOW)
2471 	return FAIL;
2472 
2473     if (last_window())
2474     {
2475 	emsg(_("E444: Cannot close last window"));
2476 	return FAIL;
2477     }
2478 
2479     if (win->w_closing || (win->w_buffer != NULL
2480 					       && win->w_buffer->b_locked > 0))
2481 	return FAIL; // window is already being closed
2482     if (win_unlisted(win))
2483     {
2484 	emsg(_(e_autocmd_close));
2485 	return FAIL;
2486     }
2487     if ((firstwin == aucmd_win || lastwin == aucmd_win) && one_window())
2488     {
2489 	emsg(_("E814: Cannot close window, only autocmd window would remain"));
2490 	return FAIL;
2491     }
2492 
2493     // When closing the last window in a tab page first go to another tab page
2494     // and then close the window and the tab page to avoid that curwin and
2495     // curtab are invalid while we are freeing memory.
2496     if (close_last_window_tabpage(win, free_buf, prev_curtab))
2497       return FAIL;
2498 
2499     // When closing the help window, try restoring a snapshot after closing
2500     // the window.  Otherwise clear the snapshot, it's now invalid.
2501     if (bt_help(win->w_buffer))
2502 	help_window = TRUE;
2503     else
2504 	clear_snapshot(curtab, SNAP_HELP_IDX);
2505 
2506     if (win == curwin)
2507     {
2508 #ifdef FEAT_JOB_CHANNEL
2509 	leaving_window(curwin);
2510 #endif
2511 	/*
2512 	 * Guess which window is going to be the new current window.
2513 	 * This may change because of the autocommands (sigh).
2514 	 */
2515 	wp = frame2win(win_altframe(win, NULL));
2516 
2517 	/*
2518 	 * Be careful: If autocommands delete the window or cause this window
2519 	 * to be the last one left, return now.
2520 	 */
2521 	if (wp->w_buffer != curbuf)
2522 	{
2523 	    other_buffer = TRUE;
2524 	    win->w_closing = TRUE;
2525 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
2526 	    if (!win_valid(win))
2527 		return FAIL;
2528 	    win->w_closing = FALSE;
2529 	    if (last_window())
2530 		return FAIL;
2531 	}
2532 	win->w_closing = TRUE;
2533 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
2534 	if (!win_valid(win))
2535 	    return FAIL;
2536 	win->w_closing = FALSE;
2537 	if (last_window())
2538 	    return FAIL;
2539 #ifdef FEAT_EVAL
2540 	// autocmds may abort script processing
2541 	if (aborting())
2542 	    return FAIL;
2543 #endif
2544     }
2545 
2546 #ifdef FEAT_GUI
2547     // Avoid trouble with scrollbars that are going to be deleted in
2548     // win_free().
2549     if (gui.in_use)
2550 	out_flush();
2551 #endif
2552 
2553 #ifdef FEAT_PROP_POPUP
2554     if (popup_win_closed(win) && !win_valid(win))
2555 	return FAIL;
2556 #endif
2557     win_close_buffer(win, free_buf ? DOBUF_UNLOAD : 0, TRUE);
2558 
2559     if (only_one_window() && win_valid(win) && win->w_buffer == NULL
2560 	    && (last_window() || curtab != prev_curtab
2561 		|| close_last_window_tabpage(win, free_buf, prev_curtab)))
2562     {
2563 	// Autocommands have closed all windows, quit now.  Restore
2564 	// curwin->w_buffer, otherwise writing viminfo may fail.
2565 	if (curwin->w_buffer == NULL)
2566 	    curwin->w_buffer = curbuf;
2567 	getout(0);
2568     }
2569 
2570     // Autocommands may have moved to another tab page.
2571     if (curtab != prev_curtab && win_valid_any_tab(win)
2572 						      && win->w_buffer == NULL)
2573     {
2574 	// Need to close the window anyway, since the buffer is NULL.
2575 	win_close_othertab(win, FALSE, prev_curtab);
2576 	return FAIL;
2577     }
2578 
2579     // Autocommands may have closed the window already or closed the only
2580     // other window.
2581     if (!win_valid(win) || last_window()
2582 	    || close_last_window_tabpage(win, free_buf, prev_curtab))
2583 	return FAIL;
2584 
2585     // Now we are really going to close the window.  Disallow any autocommand
2586     // to split a window to avoid trouble.
2587     // Also bail out of parse_queued_messages() to avoid it tries to update the
2588     // screen.
2589     ++split_disallowed;
2590 #ifdef MESSAGE_QUEUE
2591     ++dont_parse_messages;
2592 #endif
2593 
2594     // Free the memory used for the window and get the window that received
2595     // the screen space.
2596     wp = win_free_mem(win, &dir, NULL);
2597 
2598     // Make sure curwin isn't invalid.  It can cause severe trouble when
2599     // printing an error message.  For win_equal() curbuf needs to be valid
2600     // too.
2601     if (win == curwin)
2602     {
2603 	curwin = wp;
2604 #ifdef FEAT_QUICKFIX
2605 	if (wp->w_p_pvw || bt_quickfix(wp->w_buffer))
2606 	{
2607 	    /*
2608 	     * If the cursor goes to the preview or the quickfix window, try
2609 	     * finding another window to go to.
2610 	     */
2611 	    for (;;)
2612 	    {
2613 		if (wp->w_next == NULL)
2614 		    wp = firstwin;
2615 		else
2616 		    wp = wp->w_next;
2617 		if (wp == curwin)
2618 		    break;
2619 		if (!wp->w_p_pvw && !bt_quickfix(wp->w_buffer))
2620 		{
2621 		    curwin = wp;
2622 		    break;
2623 		}
2624 	    }
2625 	}
2626 #endif
2627 	curbuf = curwin->w_buffer;
2628 	close_curwin = TRUE;
2629 
2630 	// The cursor position may be invalid if the buffer changed after last
2631 	// using the window.
2632 	check_cursor();
2633     }
2634     if (p_ea && (*p_ead == 'b' || *p_ead == dir))
2635 	// If the frame of the closed window contains the new current window,
2636 	// only resize that frame.  Otherwise resize all windows.
2637 	win_equal(curwin, curwin->w_frame->fr_parent == win_frame, dir);
2638     else
2639 	win_comp_pos();
2640     if (close_curwin)
2641     {
2642 	win_enter_ext(wp, FALSE, TRUE, FALSE, TRUE, TRUE);
2643 	if (other_buffer)
2644 	    // careful: after this wp and win may be invalid!
2645 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2646     }
2647 
2648     --split_disallowed;
2649 #ifdef MESSAGE_QUEUE
2650     --dont_parse_messages;
2651 #endif
2652 
2653     /*
2654      * If last window has a status line now and we don't want one,
2655      * remove the status line.
2656      */
2657     last_status(FALSE);
2658 
2659     // After closing the help window, try restoring the window layout from
2660     // before it was opened.
2661     if (help_window)
2662 	restore_snapshot(SNAP_HELP_IDX, close_curwin);
2663 
2664 #ifdef FEAT_DIFF
2665     // If the window had 'diff' set and now there is only one window left in
2666     // the tab page with 'diff' set, and "closeoff" is in 'diffopt', then
2667     // execute ":diffoff!".
2668     if (diffopt_closeoff() && had_diffmode && curtab == prev_curtab)
2669     {
2670 	int	diffcount = 0;
2671 	win_T	*dwin;
2672 
2673 	FOR_ALL_WINDOWS(dwin)
2674 	    if (dwin->w_p_diff)
2675 		++diffcount;
2676 	if (diffcount == 1)
2677 	    do_cmdline_cmd((char_u *)"diffoff!");
2678     }
2679 #endif
2680 
2681 #if defined(FEAT_GUI)
2682     // When 'guioptions' includes 'L' or 'R' may have to remove scrollbars.
2683     if (gui.in_use && !win_hasvertsplit())
2684 	gui_init_which_components(NULL);
2685 #endif
2686 
2687     redraw_all_later(NOT_VALID);
2688     return OK;
2689 }
2690 
2691 /*
2692  * Close window "win" in tab page "tp", which is not the current tab page.
2693  * This may be the last window in that tab page and result in closing the tab,
2694  * thus "tp" may become invalid!
2695  * Caller must check if buffer is hidden and whether the tabline needs to be
2696  * updated.
2697  */
2698     void
2699 win_close_othertab(win_T *win, int free_buf, tabpage_T *tp)
2700 {
2701     win_T	*wp;
2702     int		dir;
2703     tabpage_T   *ptp = NULL;
2704     int		free_tp = FALSE;
2705 
2706     // Get here with win->w_buffer == NULL when win_close() detects the tab
2707     // page changed.
2708     if (win->w_closing || (win->w_buffer != NULL
2709 					       && win->w_buffer->b_locked > 0))
2710 	return; // window is already being closed
2711 
2712     if (win->w_buffer != NULL)
2713 	// Close the link to the buffer.
2714 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0,
2715 								 FALSE, FALSE);
2716 
2717     // Careful: Autocommands may have closed the tab page or made it the
2718     // current tab page.
2719     for (ptp = first_tabpage; ptp != NULL && ptp != tp; ptp = ptp->tp_next)
2720 	;
2721     if (ptp == NULL || tp == curtab)
2722 	return;
2723 
2724     // Autocommands may have closed the window already.
2725     for (wp = tp->tp_firstwin; wp != NULL && wp != win; wp = wp->w_next)
2726 	;
2727     if (wp == NULL)
2728 	return;
2729 
2730     // When closing the last window in a tab page remove the tab page.
2731     if (tp->tp_firstwin == tp->tp_lastwin)
2732     {
2733 	if (tp == first_tabpage)
2734 	    first_tabpage = tp->tp_next;
2735 	else
2736 	{
2737 	    for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tp;
2738 							   ptp = ptp->tp_next)
2739 		;
2740 	    if (ptp == NULL)
2741 	    {
2742 		internal_error("win_close_othertab()");
2743 		return;
2744 	    }
2745 	    ptp->tp_next = tp->tp_next;
2746 	}
2747 	free_tp = TRUE;
2748     }
2749 
2750     // Free the memory used for the window.
2751     win_free_mem(win, &dir, tp);
2752 
2753     if (free_tp)
2754 	free_tabpage(tp);
2755 }
2756 
2757 /*
2758  * Free the memory used for a window.
2759  * Returns a pointer to the window that got the freed up space.
2760  */
2761     static win_T *
2762 win_free_mem(
2763     win_T	*win,
2764     int		*dirp,		// set to 'v' or 'h' for direction if 'ea'
2765     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2766 {
2767     frame_T	*frp;
2768     win_T	*wp;
2769     tabpage_T	*win_tp = tp == NULL ? curtab : tp;
2770 
2771     // Remove the window and its frame from the tree of frames.
2772     frp = win->w_frame;
2773     wp = winframe_remove(win, dirp, tp);
2774     vim_free(frp);
2775     win_free(win, tp);
2776 
2777     // When deleting the current window in the tab, select a new current
2778     // window.
2779     if (win == win_tp->tp_curwin)
2780 	win_tp->tp_curwin = wp;
2781 
2782     return wp;
2783 }
2784 
2785 #if defined(EXITFREE) || defined(PROTO)
2786     void
2787 win_free_all(void)
2788 {
2789     int		dummy;
2790 
2791     while (first_tabpage->tp_next != NULL)
2792 	tabpage_close(TRUE);
2793 
2794     if (aucmd_win != NULL)
2795     {
2796 	(void)win_free_mem(aucmd_win, &dummy, NULL);
2797 	aucmd_win = NULL;
2798     }
2799 
2800     while (firstwin != NULL)
2801 	(void)win_free_mem(firstwin, &dummy, NULL);
2802 
2803     // No window should be used after this. Set curwin to NULL to crash
2804     // instead of using freed memory.
2805     curwin = NULL;
2806 }
2807 #endif
2808 
2809 /*
2810  * Remove a window and its frame from the tree of frames.
2811  * Returns a pointer to the window that got the freed up space.
2812  */
2813     win_T *
2814 winframe_remove(
2815     win_T	*win,
2816     int		*dirp UNUSED,	// set to 'v' or 'h' for direction if 'ea'
2817     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2818 {
2819     frame_T	*frp, *frp2, *frp3;
2820     frame_T	*frp_close = win->w_frame;
2821     win_T	*wp;
2822 
2823     /*
2824      * If there is only one window there is nothing to remove.
2825      */
2826     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2827 	return NULL;
2828 
2829     /*
2830      * Remove the window from its frame.
2831      */
2832     frp2 = win_altframe(win, tp);
2833     wp = frame2win(frp2);
2834 
2835     // Remove this frame from the list of frames.
2836     frame_remove(frp_close);
2837 
2838     if (frp_close->fr_parent->fr_layout == FR_COL)
2839     {
2840 	// When 'winfixheight' is set, try to find another frame in the column
2841 	// (as close to the closed frame as possible) to distribute the height
2842 	// to.
2843 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfh)
2844 	{
2845 	    frp = frp_close->fr_prev;
2846 	    frp3 = frp_close->fr_next;
2847 	    while (frp != NULL || frp3 != NULL)
2848 	    {
2849 		if (frp != NULL)
2850 		{
2851 		    if (!frame_fixed_height(frp))
2852 		    {
2853 			frp2 = frp;
2854 			wp = frame2win(frp2);
2855 			break;
2856 		    }
2857 		    frp = frp->fr_prev;
2858 		}
2859 		if (frp3 != NULL)
2860 		{
2861 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfh)
2862 		    {
2863 			frp2 = frp3;
2864 			wp = frp3->fr_win;
2865 			break;
2866 		    }
2867 		    frp3 = frp3->fr_next;
2868 		}
2869 	    }
2870 	}
2871 	frame_new_height(frp2, frp2->fr_height + frp_close->fr_height,
2872 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2873 	*dirp = 'v';
2874     }
2875     else
2876     {
2877 	// When 'winfixwidth' is set, try to find another frame in the column
2878 	// (as close to the closed frame as possible) to distribute the width
2879 	// to.
2880 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfw)
2881 	{
2882 	    frp = frp_close->fr_prev;
2883 	    frp3 = frp_close->fr_next;
2884 	    while (frp != NULL || frp3 != NULL)
2885 	    {
2886 		if (frp != NULL)
2887 		{
2888 		    if (!frame_fixed_width(frp))
2889 		    {
2890 			frp2 = frp;
2891 			wp = frame2win(frp2);
2892 			break;
2893 		    }
2894 		    frp = frp->fr_prev;
2895 		}
2896 		if (frp3 != NULL)
2897 		{
2898 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfw)
2899 		    {
2900 			frp2 = frp3;
2901 			wp = frp3->fr_win;
2902 			break;
2903 		    }
2904 		    frp3 = frp3->fr_next;
2905 		}
2906 	    }
2907 	}
2908 	frame_new_width(frp2, frp2->fr_width + frp_close->fr_width,
2909 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2910 	*dirp = 'h';
2911     }
2912 
2913     // If rows/columns go to a window below/right its positions need to be
2914     // updated.  Can only be done after the sizes have been updated.
2915     if (frp2 == frp_close->fr_next)
2916     {
2917 	int row = win->w_winrow;
2918 	int col = win->w_wincol;
2919 
2920 	frame_comp_pos(frp2, &row, &col);
2921     }
2922 
2923     if (frp2->fr_next == NULL && frp2->fr_prev == NULL)
2924     {
2925 	// There is no other frame in this list, move its info to the parent
2926 	// and remove it.
2927 	frp2->fr_parent->fr_layout = frp2->fr_layout;
2928 	frp2->fr_parent->fr_child = frp2->fr_child;
2929 	FOR_ALL_FRAMES(frp, frp2->fr_child)
2930 	    frp->fr_parent = frp2->fr_parent;
2931 	frp2->fr_parent->fr_win = frp2->fr_win;
2932 	if (frp2->fr_win != NULL)
2933 	    frp2->fr_win->w_frame = frp2->fr_parent;
2934 	frp = frp2->fr_parent;
2935 	if (topframe->fr_child == frp2)
2936 	    topframe->fr_child = frp;
2937 	vim_free(frp2);
2938 
2939 	frp2 = frp->fr_parent;
2940 	if (frp2 != NULL && frp2->fr_layout == frp->fr_layout)
2941 	{
2942 	    // The frame above the parent has the same layout, have to merge
2943 	    // the frames into this list.
2944 	    if (frp2->fr_child == frp)
2945 		frp2->fr_child = frp->fr_child;
2946 	    frp->fr_child->fr_prev = frp->fr_prev;
2947 	    if (frp->fr_prev != NULL)
2948 		frp->fr_prev->fr_next = frp->fr_child;
2949 	    for (frp3 = frp->fr_child; ; frp3 = frp3->fr_next)
2950 	    {
2951 		frp3->fr_parent = frp2;
2952 		if (frp3->fr_next == NULL)
2953 		{
2954 		    frp3->fr_next = frp->fr_next;
2955 		    if (frp->fr_next != NULL)
2956 			frp->fr_next->fr_prev = frp3;
2957 		    break;
2958 		}
2959 	    }
2960 	    if (topframe->fr_child == frp)
2961 		topframe->fr_child = frp2;
2962 	    vim_free(frp);
2963 	}
2964     }
2965 
2966     return wp;
2967 }
2968 
2969 /*
2970  * Return a pointer to the frame that will receive the empty screen space that
2971  * is left over after "win" is closed.
2972  *
2973  * If 'splitbelow' or 'splitright' is set, the space goes above or to the left
2974  * by default.  Otherwise, the free space goes below or to the right.  The
2975  * result is that opening a window and then immediately closing it will
2976  * preserve the initial window layout.  The 'wfh' and 'wfw' settings are
2977  * respected when possible.
2978  */
2979     static frame_T *
2980 win_altframe(
2981     win_T	*win,
2982     tabpage_T	*tp)		// tab page "win" is in, NULL for current
2983 {
2984     frame_T	*frp;
2985     frame_T	*other_fr, *target_fr;
2986 
2987     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2988 	return alt_tabpage()->tp_curwin->w_frame;
2989 
2990     frp = win->w_frame;
2991 
2992     if (frp->fr_prev == NULL)
2993 	return frp->fr_next;
2994     if (frp->fr_next == NULL)
2995 	return frp->fr_prev;
2996 
2997     // By default the next window will get the space that was abandoned by this
2998     // window
2999     target_fr = frp->fr_next;
3000     other_fr  = frp->fr_prev;
3001 
3002     // If this is part of a column of windows and 'splitbelow' is true then the
3003     // previous window will get the space.
3004     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_COL && p_sb)
3005     {
3006 	target_fr = frp->fr_prev;
3007 	other_fr  = frp->fr_next;
3008     }
3009 
3010     // If this is part of a row of windows, and 'splitright' is true then the
3011     // previous window will get the space.
3012     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW && p_spr)
3013     {
3014 	target_fr = frp->fr_prev;
3015 	other_fr  = frp->fr_next;
3016     }
3017 
3018     // If 'wfh' or 'wfw' is set for the target and not for the alternate
3019     // window, reverse the selection.
3020     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW)
3021     {
3022 	if (frame_fixed_width(target_fr) && !frame_fixed_width(other_fr))
3023 	    target_fr = other_fr;
3024     }
3025     else
3026     {
3027 	if (frame_fixed_height(target_fr) && !frame_fixed_height(other_fr))
3028 	    target_fr = other_fr;
3029     }
3030 
3031     return target_fr;
3032 }
3033 
3034 /*
3035  * Return the tabpage that will be used if the current one is closed.
3036  */
3037     static tabpage_T *
3038 alt_tabpage(void)
3039 {
3040     tabpage_T	*tp;
3041 
3042     // Use the next tab page if possible.
3043     if (curtab->tp_next != NULL)
3044 	return curtab->tp_next;
3045 
3046     // Find the last but one tab page.
3047     for (tp = first_tabpage; tp->tp_next != curtab; tp = tp->tp_next)
3048 	;
3049     return tp;
3050 }
3051 
3052 /*
3053  * Find the left-upper window in frame "frp".
3054  */
3055     static win_T *
3056 frame2win(frame_T *frp)
3057 {
3058     while (frp->fr_win == NULL)
3059 	frp = frp->fr_child;
3060     return frp->fr_win;
3061 }
3062 
3063 /*
3064  * Return TRUE if frame "frp" contains window "wp".
3065  */
3066     static int
3067 frame_has_win(frame_T *frp, win_T *wp)
3068 {
3069     frame_T	*p;
3070 
3071     if (frp->fr_layout == FR_LEAF)
3072 	return frp->fr_win == wp;
3073 
3074     FOR_ALL_FRAMES(p, frp->fr_child)
3075 	if (frame_has_win(p, wp))
3076 	    return TRUE;
3077     return FALSE;
3078 }
3079 
3080 /*
3081  * Set a new height for a frame.  Recursively sets the height for contained
3082  * frames and windows.  Caller must take care of positions.
3083  */
3084     static void
3085 frame_new_height(
3086     frame_T	*topfrp,
3087     int		height,
3088     int		topfirst,	// resize topmost contained frame first
3089     int		wfh)		// obey 'winfixheight' when there is a choice;
3090 				// may cause the height not to be set
3091 {
3092     frame_T	*frp;
3093     int		extra_lines;
3094     int		h;
3095 
3096     if (topfrp->fr_win != NULL)
3097     {
3098 	// Simple case: just one window.
3099 	win_new_height(topfrp->fr_win,
3100 				    height - topfrp->fr_win->w_status_height
3101 					      - WINBAR_HEIGHT(topfrp->fr_win));
3102     }
3103     else if (topfrp->fr_layout == FR_ROW)
3104     {
3105 	do
3106 	{
3107 	    // All frames in this row get the same new height.
3108 	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
3109 	    {
3110 		frame_new_height(frp, height, topfirst, wfh);
3111 		if (frp->fr_height > height)
3112 		{
3113 		    // Could not fit the windows, make the whole row higher.
3114 		    height = frp->fr_height;
3115 		    break;
3116 		}
3117 	    }
3118 	}
3119 	while (frp != NULL);
3120     }
3121     else    // fr_layout == FR_COL
3122     {
3123 	// Complicated case: Resize a column of frames.  Resize the bottom
3124 	// frame first, frames above that when needed.
3125 
3126 	frp = topfrp->fr_child;
3127 	if (wfh)
3128 	    // Advance past frames with one window with 'wfh' set.
3129 	    while (frame_fixed_height(frp))
3130 	    {
3131 		frp = frp->fr_next;
3132 		if (frp == NULL)
3133 		    return;	    // no frame without 'wfh', give up
3134 	    }
3135 	if (!topfirst)
3136 	{
3137 	    // Find the bottom frame of this column
3138 	    while (frp->fr_next != NULL)
3139 		frp = frp->fr_next;
3140 	    if (wfh)
3141 		// Advance back for frames with one window with 'wfh' set.
3142 		while (frame_fixed_height(frp))
3143 		    frp = frp->fr_prev;
3144 	}
3145 
3146 	extra_lines = height - topfrp->fr_height;
3147 	if (extra_lines < 0)
3148 	{
3149 	    // reduce height of contained frames, bottom or top frame first
3150 	    while (frp != NULL)
3151 	    {
3152 		h = frame_minheight(frp, NULL);
3153 		if (frp->fr_height + extra_lines < h)
3154 		{
3155 		    extra_lines += frp->fr_height - h;
3156 		    frame_new_height(frp, h, topfirst, wfh);
3157 		}
3158 		else
3159 		{
3160 		    frame_new_height(frp, frp->fr_height + extra_lines,
3161 							       topfirst, wfh);
3162 		    break;
3163 		}
3164 		if (topfirst)
3165 		{
3166 		    do
3167 			frp = frp->fr_next;
3168 		    while (wfh && frp != NULL && frame_fixed_height(frp));
3169 		}
3170 		else
3171 		{
3172 		    do
3173 			frp = frp->fr_prev;
3174 		    while (wfh && frp != NULL && frame_fixed_height(frp));
3175 		}
3176 		// Increase "height" if we could not reduce enough frames.
3177 		if (frp == NULL)
3178 		    height -= extra_lines;
3179 	    }
3180 	}
3181 	else if (extra_lines > 0)
3182 	{
3183 	    // increase height of bottom or top frame
3184 	    frame_new_height(frp, frp->fr_height + extra_lines, topfirst, wfh);
3185 	}
3186     }
3187     topfrp->fr_height = height;
3188 }
3189 
3190 /*
3191  * Return TRUE if height of frame "frp" should not be changed because of
3192  * the 'winfixheight' option.
3193  */
3194     static int
3195 frame_fixed_height(frame_T *frp)
3196 {
3197     // frame with one window: fixed height if 'winfixheight' set.
3198     if (frp->fr_win != NULL)
3199 	return frp->fr_win->w_p_wfh;
3200 
3201     if (frp->fr_layout == FR_ROW)
3202     {
3203 	// The frame is fixed height if one of the frames in the row is fixed
3204 	// height.
3205 	FOR_ALL_FRAMES(frp, frp->fr_child)
3206 	    if (frame_fixed_height(frp))
3207 		return TRUE;
3208 	return FALSE;
3209     }
3210 
3211     // frp->fr_layout == FR_COL: The frame is fixed height if all of the
3212     // frames in the row are fixed height.
3213     FOR_ALL_FRAMES(frp, frp->fr_child)
3214 	if (!frame_fixed_height(frp))
3215 	    return FALSE;
3216     return TRUE;
3217 }
3218 
3219 /*
3220  * Return TRUE if width of frame "frp" should not be changed because of
3221  * the 'winfixwidth' option.
3222  */
3223     static int
3224 frame_fixed_width(frame_T *frp)
3225 {
3226     // frame with one window: fixed width if 'winfixwidth' set.
3227     if (frp->fr_win != NULL)
3228 	return frp->fr_win->w_p_wfw;
3229 
3230     if (frp->fr_layout == FR_COL)
3231     {
3232 	// The frame is fixed width if one of the frames in the row is fixed
3233 	// width.
3234 	FOR_ALL_FRAMES(frp, frp->fr_child)
3235 	    if (frame_fixed_width(frp))
3236 		return TRUE;
3237 	return FALSE;
3238     }
3239 
3240     // frp->fr_layout == FR_ROW: The frame is fixed width if all of the
3241     // frames in the row are fixed width.
3242     FOR_ALL_FRAMES(frp, frp->fr_child)
3243 	if (!frame_fixed_width(frp))
3244 	    return FALSE;
3245     return TRUE;
3246 }
3247 
3248 /*
3249  * Add a status line to windows at the bottom of "frp".
3250  * Note: Does not check if there is room!
3251  */
3252     static void
3253 frame_add_statusline(frame_T *frp)
3254 {
3255     win_T	*wp;
3256 
3257     if (frp->fr_layout == FR_LEAF)
3258     {
3259 	wp = frp->fr_win;
3260 	if (wp->w_status_height == 0)
3261 	{
3262 	    if (wp->w_height > 0)	// don't make it negative
3263 		--wp->w_height;
3264 	    wp->w_status_height = STATUS_HEIGHT;
3265 	}
3266     }
3267     else if (frp->fr_layout == FR_ROW)
3268     {
3269 	// Handle all the frames in the row.
3270 	FOR_ALL_FRAMES(frp, frp->fr_child)
3271 	    frame_add_statusline(frp);
3272     }
3273     else // frp->fr_layout == FR_COL
3274     {
3275 	// Only need to handle the last frame in the column.
3276 	for (frp = frp->fr_child; frp->fr_next != NULL; frp = frp->fr_next)
3277 	    ;
3278 	frame_add_statusline(frp);
3279     }
3280 }
3281 
3282 /*
3283  * Set width of a frame.  Handles recursively going through contained frames.
3284  * May remove separator line for windows at the right side (for win_close()).
3285  */
3286     static void
3287 frame_new_width(
3288     frame_T	*topfrp,
3289     int		width,
3290     int		leftfirst,	// resize leftmost contained frame first
3291     int		wfw)		// obey 'winfixwidth' when there is a choice;
3292 				// may cause the width not to be set
3293 {
3294     frame_T	*frp;
3295     int		extra_cols;
3296     int		w;
3297     win_T	*wp;
3298 
3299     if (topfrp->fr_layout == FR_LEAF)
3300     {
3301 	// Simple case: just one window.
3302 	wp = topfrp->fr_win;
3303 	// Find out if there are any windows right of this one.
3304 	for (frp = topfrp; frp->fr_parent != NULL; frp = frp->fr_parent)
3305 	    if (frp->fr_parent->fr_layout == FR_ROW && frp->fr_next != NULL)
3306 		break;
3307 	if (frp->fr_parent == NULL)
3308 	    wp->w_vsep_width = 0;
3309 	win_new_width(wp, width - wp->w_vsep_width);
3310     }
3311     else if (topfrp->fr_layout == FR_COL)
3312     {
3313 	do
3314 	{
3315 	    // All frames in this column get the same new width.
3316 	    FOR_ALL_FRAMES(frp, topfrp->fr_child)
3317 	    {
3318 		frame_new_width(frp, width, leftfirst, wfw);
3319 		if (frp->fr_width > width)
3320 		{
3321 		    // Could not fit the windows, make whole column wider.
3322 		    width = frp->fr_width;
3323 		    break;
3324 		}
3325 	    }
3326 	} while (frp != NULL);
3327     }
3328     else    // fr_layout == FR_ROW
3329     {
3330 	// Complicated case: Resize a row of frames.  Resize the rightmost
3331 	// frame first, frames left of it when needed.
3332 
3333 	frp = topfrp->fr_child;
3334 	if (wfw)
3335 	    // Advance past frames with one window with 'wfw' set.
3336 	    while (frame_fixed_width(frp))
3337 	    {
3338 		frp = frp->fr_next;
3339 		if (frp == NULL)
3340 		    return;	    // no frame without 'wfw', give up
3341 	    }
3342 	if (!leftfirst)
3343 	{
3344 	    // Find the rightmost frame of this row
3345 	    while (frp->fr_next != NULL)
3346 		frp = frp->fr_next;
3347 	    if (wfw)
3348 		// Advance back for frames with one window with 'wfw' set.
3349 		while (frame_fixed_width(frp))
3350 		    frp = frp->fr_prev;
3351 	}
3352 
3353 	extra_cols = width - topfrp->fr_width;
3354 	if (extra_cols < 0)
3355 	{
3356 	    // reduce frame width, rightmost frame first
3357 	    while (frp != NULL)
3358 	    {
3359 		w = frame_minwidth(frp, NULL);
3360 		if (frp->fr_width + extra_cols < w)
3361 		{
3362 		    extra_cols += frp->fr_width - w;
3363 		    frame_new_width(frp, w, leftfirst, wfw);
3364 		}
3365 		else
3366 		{
3367 		    frame_new_width(frp, frp->fr_width + extra_cols,
3368 							      leftfirst, wfw);
3369 		    break;
3370 		}
3371 		if (leftfirst)
3372 		{
3373 		    do
3374 			frp = frp->fr_next;
3375 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3376 		}
3377 		else
3378 		{
3379 		    do
3380 			frp = frp->fr_prev;
3381 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3382 		}
3383 		// Increase "width" if we could not reduce enough frames.
3384 		if (frp == NULL)
3385 		    width -= extra_cols;
3386 	    }
3387 	}
3388 	else if (extra_cols > 0)
3389 	{
3390 	    // increase width of rightmost frame
3391 	    frame_new_width(frp, frp->fr_width + extra_cols, leftfirst, wfw);
3392 	}
3393     }
3394     topfrp->fr_width = width;
3395 }
3396 
3397 /*
3398  * Add the vertical separator to windows at the right side of "frp".
3399  * Note: Does not check if there is room!
3400  */
3401     static void
3402 frame_add_vsep(frame_T *frp)
3403 {
3404     win_T	*wp;
3405 
3406     if (frp->fr_layout == FR_LEAF)
3407     {
3408 	wp = frp->fr_win;
3409 	if (wp->w_vsep_width == 0)
3410 	{
3411 	    if (wp->w_width > 0)	// don't make it negative
3412 		--wp->w_width;
3413 	    wp->w_vsep_width = 1;
3414 	}
3415     }
3416     else if (frp->fr_layout == FR_COL)
3417     {
3418 	// Handle all the frames in the column.
3419 	FOR_ALL_FRAMES(frp, frp->fr_child)
3420 	    frame_add_vsep(frp);
3421     }
3422     else // frp->fr_layout == FR_ROW
3423     {
3424 	// Only need to handle the last frame in the row.
3425 	frp = frp->fr_child;
3426 	while (frp->fr_next != NULL)
3427 	    frp = frp->fr_next;
3428 	frame_add_vsep(frp);
3429     }
3430 }
3431 
3432 /*
3433  * Set frame width from the window it contains.
3434  */
3435     static void
3436 frame_fix_width(win_T *wp)
3437 {
3438     wp->w_frame->fr_width = wp->w_width + wp->w_vsep_width;
3439 }
3440 
3441 /*
3442  * Set frame height from the window it contains.
3443  */
3444     static void
3445 frame_fix_height(win_T *wp)
3446 {
3447     wp->w_frame->fr_height = VISIBLE_HEIGHT(wp) + wp->w_status_height;
3448 }
3449 
3450 /*
3451  * Compute the minimal height for frame "topfrp".
3452  * Uses the 'winminheight' option.
3453  * When "next_curwin" isn't NULL, use p_wh for this window.
3454  * When "next_curwin" is NOWIN, don't use at least one line for the current
3455  * window.
3456  */
3457     static int
3458 frame_minheight(frame_T *topfrp, win_T *next_curwin)
3459 {
3460     frame_T	*frp;
3461     int		m;
3462     int		n;
3463 
3464     if (topfrp->fr_win != NULL)
3465     {
3466 	if (topfrp->fr_win == next_curwin)
3467 	    m = p_wh + topfrp->fr_win->w_status_height;
3468 	else
3469 	{
3470 	    // window: minimal height of the window plus status line
3471 	    m = p_wmh + topfrp->fr_win->w_status_height;
3472 	    if (topfrp->fr_win == curwin && next_curwin == NULL)
3473 	    {
3474 		// Current window is minimal one line high and WinBar is
3475 		// visible.
3476 		if (p_wmh == 0)
3477 		    ++m;
3478 		m += WINBAR_HEIGHT(curwin);
3479 	    }
3480 	}
3481     }
3482     else if (topfrp->fr_layout == FR_ROW)
3483     {
3484 	// get the minimal height from each frame in this row
3485 	m = 0;
3486 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3487 	{
3488 	    n = frame_minheight(frp, next_curwin);
3489 	    if (n > m)
3490 		m = n;
3491 	}
3492     }
3493     else
3494     {
3495 	// Add up the minimal heights for all frames in this column.
3496 	m = 0;
3497 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3498 	    m += frame_minheight(frp, next_curwin);
3499     }
3500 
3501     return m;
3502 }
3503 
3504 /*
3505  * Compute the minimal width for frame "topfrp".
3506  * When "next_curwin" isn't NULL, use p_wiw for this window.
3507  * When "next_curwin" is NOWIN, don't use at least one column for the current
3508  * window.
3509  */
3510     static int
3511 frame_minwidth(
3512     frame_T	*topfrp,
3513     win_T	*next_curwin)	// use p_wh and p_wiw for next_curwin
3514 {
3515     frame_T	*frp;
3516     int		m, n;
3517 
3518     if (topfrp->fr_win != NULL)
3519     {
3520 	if (topfrp->fr_win == next_curwin)
3521 	    m = p_wiw + topfrp->fr_win->w_vsep_width;
3522 	else
3523 	{
3524 	    // window: minimal width of the window plus separator column
3525 	    m = p_wmw + topfrp->fr_win->w_vsep_width;
3526 	    // Current window is minimal one column wide
3527 	    if (p_wmw == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3528 		++m;
3529 	}
3530     }
3531     else if (topfrp->fr_layout == FR_COL)
3532     {
3533 	// get the minimal width from each frame in this column
3534 	m = 0;
3535 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3536 	{
3537 	    n = frame_minwidth(frp, next_curwin);
3538 	    if (n > m)
3539 		m = n;
3540 	}
3541     }
3542     else
3543     {
3544 	// Add up the minimal widths for all frames in this row.
3545 	m = 0;
3546 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
3547 	    m += frame_minwidth(frp, next_curwin);
3548     }
3549 
3550     return m;
3551 }
3552 
3553 
3554 /*
3555  * Try to close all windows except current one.
3556  * Buffers in the other windows become hidden if 'hidden' is set, or '!' is
3557  * used and the buffer was modified.
3558  *
3559  * Used by ":bdel" and ":only".
3560  */
3561     void
3562 close_others(
3563     int		message,
3564     int		forceit)	    // always hide all other windows
3565 {
3566     win_T	*wp;
3567     win_T	*nextwp;
3568     int		r;
3569 
3570     if (one_window())
3571     {
3572 	if (message && !autocmd_busy)
3573 	    msg(_(m_onlyone));
3574 	return;
3575     }
3576 
3577     // Be very careful here: autocommands may change the window layout.
3578     for (wp = firstwin; win_valid(wp); wp = nextwp)
3579     {
3580 	nextwp = wp->w_next;
3581 	if (wp != curwin)		// don't close current window
3582 	{
3583 
3584 	    // Check if it's allowed to abandon this window
3585 	    r = can_abandon(wp->w_buffer, forceit);
3586 	    if (!win_valid(wp))		// autocommands messed wp up
3587 	    {
3588 		nextwp = firstwin;
3589 		continue;
3590 	    }
3591 	    if (!r)
3592 	    {
3593 #if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
3594 		if (message && (p_confirm
3595 			     || (cmdmod.cmod_flags & CMOD_CONFIRM)) && p_write)
3596 		{
3597 		    dialog_changed(wp->w_buffer, FALSE);
3598 		    if (!win_valid(wp))		// autocommands messed wp up
3599 		    {
3600 			nextwp = firstwin;
3601 			continue;
3602 		    }
3603 		}
3604 		if (bufIsChanged(wp->w_buffer))
3605 #endif
3606 		    continue;
3607 	    }
3608 	    win_close(wp, !buf_hide(wp->w_buffer)
3609 					       && !bufIsChanged(wp->w_buffer));
3610 	}
3611     }
3612 
3613     if (message && !ONE_WINDOW)
3614 	emsg(_("E445: Other window contains changes"));
3615 }
3616 
3617     static void
3618 win_init_empty(win_T *wp)
3619 {
3620     redraw_win_later(wp, NOT_VALID);
3621     wp->w_lines_valid = 0;
3622     wp->w_cursor.lnum = 1;
3623     wp->w_curswant = wp->w_cursor.col = 0;
3624     wp->w_cursor.coladd = 0;
3625     wp->w_pcmark.lnum = 1;	// pcmark not cleared but set to line 1
3626     wp->w_pcmark.col = 0;
3627     wp->w_prev_pcmark.lnum = 0;
3628     wp->w_prev_pcmark.col = 0;
3629     wp->w_topline = 1;
3630 #ifdef FEAT_DIFF
3631     wp->w_topfill = 0;
3632 #endif
3633     wp->w_botline = 2;
3634 #if defined(FEAT_SYN_HL) || defined(FEAT_SPELL)
3635     wp->w_s = &wp->w_buffer->b_s;
3636 #endif
3637 }
3638 
3639 /*
3640  * Init the current window "curwin".
3641  * Called when a new file is being edited.
3642  */
3643     void
3644 curwin_init(void)
3645 {
3646     win_init_empty(curwin);
3647 }
3648 
3649 /*
3650  * Allocate the first window and put an empty buffer in it.
3651  * Called from main().
3652  * Return FAIL when something goes wrong (out of memory).
3653  */
3654     int
3655 win_alloc_first(void)
3656 {
3657     if (win_alloc_firstwin(NULL) == FAIL)
3658 	return FAIL;
3659 
3660     first_tabpage = alloc_tabpage();
3661     if (first_tabpage == NULL)
3662 	return FAIL;
3663     first_tabpage->tp_topframe = topframe;
3664     curtab = first_tabpage;
3665     curtab->tp_firstwin = firstwin;
3666     curtab->tp_lastwin = lastwin;
3667     curtab->tp_curwin = curwin;
3668 
3669     return OK;
3670 }
3671 
3672 /*
3673  * Allocate and init a window that is not a regular window.
3674  * This can only be done after the first window is fully initialized, thus it
3675  * can't be in win_alloc_first().
3676  */
3677     win_T *
3678 win_alloc_popup_win(void)
3679 {
3680     win_T *wp;
3681 
3682     wp = win_alloc(NULL, TRUE);
3683     if (wp != NULL)
3684     {
3685 	// We need to initialize options with something, using the current
3686 	// window makes most sense.
3687 	win_init_some(wp, curwin);
3688 
3689 	RESET_BINDING(wp);
3690 	new_frame(wp);
3691     }
3692     return wp;
3693 }
3694 
3695 /*
3696  * Initialize window "wp" to display buffer "buf".
3697  */
3698     void
3699 win_init_popup_win(win_T *wp, buf_T *buf)
3700 {
3701     wp->w_buffer = buf;
3702     ++buf->b_nwindows;
3703     win_init_empty(wp); // set cursor and topline to safe values
3704 
3705     // Make sure w_localdir and globaldir are NULL to avoid a chdir() in
3706     // win_enter_ext().
3707     VIM_CLEAR(wp->w_localdir);
3708 }
3709 
3710 /*
3711  * Allocate the first window or the first window in a new tab page.
3712  * When "oldwin" is NULL create an empty buffer for it.
3713  * When "oldwin" is not NULL copy info from it to the new window.
3714  * Return FAIL when something goes wrong (out of memory).
3715  */
3716     static int
3717 win_alloc_firstwin(win_T *oldwin)
3718 {
3719     curwin = win_alloc(NULL, FALSE);
3720     if (oldwin == NULL)
3721     {
3722 	// Very first window, need to create an empty buffer for it and
3723 	// initialize from scratch.
3724 	curbuf = buflist_new(NULL, NULL, 1L, BLN_LISTED);
3725 	if (curwin == NULL || curbuf == NULL)
3726 	    return FAIL;
3727 	curwin->w_buffer = curbuf;
3728 #ifdef FEAT_SYN_HL
3729 	curwin->w_s = &(curbuf->b_s);
3730 #endif
3731 	curbuf->b_nwindows = 1;	// there is one window
3732 	curwin->w_alist = &global_alist;
3733 	curwin_init();		// init current window
3734     }
3735     else
3736     {
3737 	// First window in new tab page, initialize it from "oldwin".
3738 	win_init(curwin, oldwin, 0);
3739 
3740 	// We don't want cursor- and scroll-binding in the first window.
3741 	RESET_BINDING(curwin);
3742     }
3743 
3744     new_frame(curwin);
3745     if (curwin->w_frame == NULL)
3746 	return FAIL;
3747     topframe = curwin->w_frame;
3748     topframe->fr_width = Columns;
3749     topframe->fr_height = Rows - p_ch;
3750 
3751     return OK;
3752 }
3753 
3754 /*
3755  * Create a frame for window "wp".
3756  */
3757     static void
3758 new_frame(win_T *wp)
3759 {
3760     frame_T *frp = ALLOC_CLEAR_ONE(frame_T);
3761 
3762     wp->w_frame = frp;
3763     if (frp != NULL)
3764     {
3765 	frp->fr_layout = FR_LEAF;
3766 	frp->fr_win = wp;
3767     }
3768 }
3769 
3770 /*
3771  * Initialize the window and frame size to the maximum.
3772  */
3773     void
3774 win_init_size(void)
3775 {
3776     firstwin->w_height = ROWS_AVAIL;
3777     topframe->fr_height = ROWS_AVAIL;
3778     firstwin->w_width = Columns;
3779     topframe->fr_width = Columns;
3780 }
3781 
3782 /*
3783  * Allocate a new tabpage_T and init the values.
3784  * Returns NULL when out of memory.
3785  */
3786     static tabpage_T *
3787 alloc_tabpage(void)
3788 {
3789     tabpage_T	*tp;
3790 # ifdef FEAT_GUI
3791     int		i;
3792 # endif
3793 
3794 
3795     tp = ALLOC_CLEAR_ONE(tabpage_T);
3796     if (tp == NULL)
3797 	return NULL;
3798 
3799 # ifdef FEAT_EVAL
3800     // init t: variables
3801     tp->tp_vars = dict_alloc();
3802     if (tp->tp_vars == NULL)
3803     {
3804 	vim_free(tp);
3805 	return NULL;
3806     }
3807     init_var_dict(tp->tp_vars, &tp->tp_winvar, VAR_SCOPE);
3808 # endif
3809 
3810 # ifdef FEAT_GUI
3811     for (i = 0; i < 3; i++)
3812 	tp->tp_prev_which_scrollbars[i] = -1;
3813 # endif
3814 # ifdef FEAT_DIFF
3815     tp->tp_diff_invalid = TRUE;
3816 # endif
3817     tp->tp_ch_used = p_ch;
3818 
3819     return tp;
3820 }
3821 
3822     void
3823 free_tabpage(tabpage_T *tp)
3824 {
3825     int idx;
3826 
3827 # ifdef FEAT_DIFF
3828     diff_clear(tp);
3829 # endif
3830 # ifdef FEAT_PROP_POPUP
3831     while (tp->tp_first_popupwin != NULL)
3832 	popup_close_tabpage(tp, tp->tp_first_popupwin->w_id, TRUE);
3833 #endif
3834     for (idx = 0; idx < SNAP_COUNT; ++idx)
3835 	clear_snapshot(tp, idx);
3836 #ifdef FEAT_EVAL
3837     vars_clear(&tp->tp_vars->dv_hashtab);	// free all t: variables
3838     hash_init(&tp->tp_vars->dv_hashtab);
3839     unref_var_dict(tp->tp_vars);
3840 #endif
3841 
3842     if (tp == lastused_tabpage)
3843 	lastused_tabpage = NULL;
3844 
3845     vim_free(tp->tp_localdir);
3846     vim_free(tp->tp_prevdir);
3847 
3848 #ifdef FEAT_PYTHON
3849     python_tabpage_free(tp);
3850 #endif
3851 
3852 #ifdef FEAT_PYTHON3
3853     python3_tabpage_free(tp);
3854 #endif
3855 
3856     vim_free(tp);
3857 }
3858 
3859 /*
3860  * Create a new Tab page with one window.
3861  * It will edit the current buffer, like after ":split".
3862  * When "after" is 0 put it just after the current Tab page.
3863  * Otherwise put it just before tab page "after".
3864  * Return FAIL or OK.
3865  */
3866     int
3867 win_new_tabpage(int after)
3868 {
3869     tabpage_T	*tp = curtab;
3870     tabpage_T	*prev_tp = curtab;
3871     tabpage_T	*newtp;
3872     int		n;
3873 
3874     newtp = alloc_tabpage();
3875     if (newtp == NULL)
3876 	return FAIL;
3877 
3878     // Remember the current windows in this Tab page.
3879     if (leave_tabpage(curbuf, TRUE) == FAIL)
3880     {
3881 	vim_free(newtp);
3882 	return FAIL;
3883     }
3884     curtab = newtp;
3885 
3886     newtp->tp_localdir = (tp->tp_localdir == NULL)
3887 				    ? NULL : vim_strsave(tp->tp_localdir);
3888     // Create a new empty window.
3889     if (win_alloc_firstwin(tp->tp_curwin) == OK)
3890     {
3891 	// Make the new Tab page the new topframe.
3892 	if (after == 1)
3893 	{
3894 	    // New tab page becomes the first one.
3895 	    newtp->tp_next = first_tabpage;
3896 	    first_tabpage = newtp;
3897 	}
3898 	else
3899 	{
3900 	    if (after > 0)
3901 	    {
3902 		// Put new tab page before tab page "after".
3903 		n = 2;
3904 		for (tp = first_tabpage; tp->tp_next != NULL
3905 					       && n < after; tp = tp->tp_next)
3906 		    ++n;
3907 	    }
3908 	    newtp->tp_next = tp->tp_next;
3909 	    tp->tp_next = newtp;
3910 	}
3911 	newtp->tp_firstwin = newtp->tp_lastwin = newtp->tp_curwin = curwin;
3912 
3913 	win_init_size();
3914 	firstwin->w_winrow = tabline_height();
3915 	win_comp_scroll(curwin);
3916 
3917 	newtp->tp_topframe = topframe;
3918 	last_status(FALSE);
3919 
3920 	lastused_tabpage = prev_tp;
3921 
3922 #if defined(FEAT_GUI)
3923 	// When 'guioptions' includes 'L' or 'R' may have to remove or add
3924 	// scrollbars.  Have to update them anyway.
3925 	gui_may_update_scrollbars();
3926 #endif
3927 #ifdef FEAT_JOB_CHANNEL
3928 	entering_window(curwin);
3929 #endif
3930 
3931 	redraw_all_later(NOT_VALID);
3932 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
3933 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
3934 	apply_autocmds(EVENT_TABNEW, NULL, NULL, FALSE, curbuf);
3935 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3936 	return OK;
3937     }
3938 
3939     // Failed, get back the previous Tab page
3940     enter_tabpage(curtab, curbuf, TRUE, TRUE);
3941     return FAIL;
3942 }
3943 
3944 /*
3945  * Open a new tab page if ":tab cmd" was used.  It will edit the same buffer,
3946  * like with ":split".
3947  * Returns OK if a new tab page was created, FAIL otherwise.
3948  */
3949     static int
3950 may_open_tabpage(void)
3951 {
3952     int		n = (cmdmod.cmod_tab == 0)
3953 				       ? postponed_split_tab : cmdmod.cmod_tab;
3954 
3955     if (n != 0)
3956     {
3957 	cmdmod.cmod_tab = 0;	    // reset it to avoid doing it twice
3958 	postponed_split_tab = 0;
3959 	return win_new_tabpage(n);
3960     }
3961     return FAIL;
3962 }
3963 
3964 /*
3965  * Create up to "maxcount" tabpages with empty windows.
3966  * Returns the number of resulting tab pages.
3967  */
3968     int
3969 make_tabpages(int maxcount)
3970 {
3971     int		count = maxcount;
3972     int		todo;
3973 
3974     // Limit to 'tabpagemax' tabs.
3975     if (count > p_tpm)
3976 	count = p_tpm;
3977 
3978     /*
3979      * Don't execute autocommands while creating the tab pages.  Must do that
3980      * when putting the buffers in the windows.
3981      */
3982     block_autocmds();
3983 
3984     for (todo = count - 1; todo > 0; --todo)
3985 	if (win_new_tabpage(0) == FAIL)
3986 	    break;
3987 
3988     unblock_autocmds();
3989 
3990     // return actual number of tab pages
3991     return (count - todo);
3992 }
3993 
3994 /*
3995  * Return TRUE when "tpc" points to a valid tab page.
3996  */
3997     int
3998 valid_tabpage(tabpage_T *tpc)
3999 {
4000     tabpage_T	*tp;
4001 
4002     FOR_ALL_TABPAGES(tp)
4003 	if (tp == tpc)
4004 	    return TRUE;
4005     return FALSE;
4006 }
4007 
4008 /*
4009  * Return TRUE when "tpc" points to a valid tab page and at least one window is
4010  * valid.
4011  */
4012     int
4013 valid_tabpage_win(tabpage_T *tpc)
4014 {
4015     tabpage_T	*tp;
4016     win_T	*wp;
4017 
4018     FOR_ALL_TABPAGES(tp)
4019     {
4020 	if (tp == tpc)
4021 	{
4022 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
4023 	    {
4024 		if (win_valid_any_tab(wp))
4025 		    return TRUE;
4026 	    }
4027 	    return FALSE;
4028 	}
4029     }
4030     // shouldn't happen
4031     return FALSE;
4032 }
4033 
4034 /*
4035  * Close tabpage "tab", assuming it has no windows in it.
4036  * There must be another tabpage or this will crash.
4037  */
4038     void
4039 close_tabpage(tabpage_T *tab)
4040 {
4041     tabpage_T	*ptp;
4042 
4043     if (tab == first_tabpage)
4044     {
4045 	first_tabpage = tab->tp_next;
4046 	ptp = first_tabpage;
4047     }
4048     else
4049     {
4050 	for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tab;
4051 							    ptp = ptp->tp_next)
4052 	    ;
4053 	assert(ptp != NULL);
4054 	ptp->tp_next = tab->tp_next;
4055     }
4056 
4057     goto_tabpage_tp(ptp, FALSE, FALSE);
4058     free_tabpage(tab);
4059 }
4060 
4061 /*
4062  * Find tab page "n" (first one is 1).  Returns NULL when not found.
4063  */
4064     tabpage_T *
4065 find_tabpage(int n)
4066 {
4067     tabpage_T	*tp;
4068     int		i = 1;
4069 
4070     if (n == 0)
4071 	return curtab;
4072 
4073     for (tp = first_tabpage; tp != NULL && i != n; tp = tp->tp_next)
4074 	++i;
4075     return tp;
4076 }
4077 
4078 /*
4079  * Get index of tab page "tp".  First one has index 1.
4080  * When not found returns number of tab pages plus one.
4081  */
4082     int
4083 tabpage_index(tabpage_T *ftp)
4084 {
4085     int		i = 1;
4086     tabpage_T	*tp;
4087 
4088     for (tp = first_tabpage; tp != NULL && tp != ftp; tp = tp->tp_next)
4089 	++i;
4090     return i;
4091 }
4092 
4093 /*
4094  * Prepare for leaving the current tab page.
4095  * When autocommands change "curtab" we don't leave the tab page and return
4096  * FAIL.
4097  * Careful: When OK is returned need to get a new tab page very very soon!
4098  */
4099     static int
4100 leave_tabpage(
4101     buf_T	*new_curbuf UNUSED,    // what is going to be the new curbuf,
4102 				       // NULL if unknown
4103     int		trigger_leave_autocmds UNUSED)
4104 {
4105     tabpage_T	*tp = curtab;
4106 
4107 #ifdef FEAT_JOB_CHANNEL
4108     leaving_window(curwin);
4109 #endif
4110     reset_VIsual_and_resel();	// stop Visual mode
4111     if (trigger_leave_autocmds)
4112     {
4113 	if (new_curbuf != curbuf)
4114 	{
4115 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4116 	    if (curtab != tp)
4117 		return FAIL;
4118 	}
4119 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4120 	if (curtab != tp)
4121 	    return FAIL;
4122 	apply_autocmds(EVENT_TABLEAVE, NULL, NULL, FALSE, curbuf);
4123 	if (curtab != tp)
4124 	    return FAIL;
4125     }
4126 #if defined(FEAT_GUI)
4127     // Remove the scrollbars.  They may be added back later.
4128     if (gui.in_use)
4129 	gui_remove_scrollbars();
4130 #endif
4131     tp->tp_curwin = curwin;
4132     tp->tp_prevwin = prevwin;
4133     tp->tp_firstwin = firstwin;
4134     tp->tp_lastwin = lastwin;
4135     tp->tp_old_Rows = Rows;
4136     tp->tp_old_Columns = Columns;
4137     firstwin = NULL;
4138     lastwin = NULL;
4139     return OK;
4140 }
4141 
4142 /*
4143  * Start using tab page "tp".
4144  * Only to be used after leave_tabpage() or freeing the current tab page.
4145  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4146  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4147  */
4148     static void
4149 enter_tabpage(
4150     tabpage_T	*tp,
4151     buf_T	*old_curbuf UNUSED,
4152     int		trigger_enter_autocmds,
4153     int		trigger_leave_autocmds)
4154 {
4155     int		row;
4156     int		old_off = tp->tp_firstwin->w_winrow;
4157     win_T	*next_prevwin = tp->tp_prevwin;
4158     tabpage_T	*last_tab = curtab;
4159 
4160     curtab = tp;
4161     firstwin = tp->tp_firstwin;
4162     lastwin = tp->tp_lastwin;
4163     topframe = tp->tp_topframe;
4164 
4165     // We would like doing the TabEnter event first, but we don't have a
4166     // valid current window yet, which may break some commands.
4167     // This triggers autocommands, thus may make "tp" invalid.
4168     win_enter_ext(tp->tp_curwin, FALSE, TRUE, FALSE,
4169 			      trigger_enter_autocmds, trigger_leave_autocmds);
4170     prevwin = next_prevwin;
4171 
4172     last_status(FALSE);		// status line may appear or disappear
4173     row = win_comp_pos();	// recompute w_winrow for all windows
4174 #ifdef FEAT_DIFF
4175     diff_need_scrollbind = TRUE;
4176 #endif
4177 
4178     // The tabpage line may have appeared or disappeared, may need to resize
4179     // the frames for that.  When the Vim window was resized need to update
4180     // frame sizes too.  Use the stored value of p_ch, so that it can be
4181     // different for each tab page.
4182     if (p_ch != curtab->tp_ch_used)
4183 	clear_cmdline = TRUE;
4184     p_ch = curtab->tp_ch_used;
4185 
4186     // When cmdheight is changed in a tab page with '<C-w>-', cmdline_row is
4187     // changed but p_ch and tp_ch_used are not changed. Thus we also need to
4188     // check cmdline_row.
4189     if ((row < cmdline_row) && (cmdline_row <= Rows - p_ch))
4190 	clear_cmdline = TRUE;
4191 
4192     if (curtab->tp_old_Rows != Rows || (old_off != firstwin->w_winrow
4193 #ifdef FEAT_GUI_TABLINE
4194 			    && !gui_use_tabline()
4195 #endif
4196 		))
4197 	shell_new_rows();
4198     if (curtab->tp_old_Columns != Columns && starting == 0)
4199 	shell_new_columns();	// update window widths
4200 
4201     lastused_tabpage = last_tab;
4202 
4203 #if defined(FEAT_GUI)
4204     // When 'guioptions' includes 'L' or 'R' may have to remove or add
4205     // scrollbars.  Have to update them anyway.
4206     gui_may_update_scrollbars();
4207 #endif
4208 
4209     // Apply autocommands after updating the display, when 'rows' and
4210     // 'columns' have been set correctly.
4211     if (trigger_enter_autocmds)
4212     {
4213 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
4214 	if (old_curbuf != curbuf)
4215 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4216     }
4217 
4218     redraw_all_later(NOT_VALID);
4219 }
4220 
4221 /*
4222  * Go to tab page "n".  For ":tab N" and "Ngt".
4223  * When "n" is 9999 go to the last tab page.
4224  */
4225     void
4226 goto_tabpage(int n)
4227 {
4228     tabpage_T	*tp = NULL;  // shut up compiler
4229     tabpage_T	*ttp;
4230     int		i;
4231 
4232     if (text_locked())
4233     {
4234 	// Not allowed when editing the command line.
4235 	text_locked_msg();
4236 	return;
4237     }
4238 
4239     // If there is only one it can't work.
4240     if (first_tabpage->tp_next == NULL)
4241     {
4242 	if (n > 1)
4243 	    beep_flush();
4244 	return;
4245     }
4246 
4247     if (n == 0)
4248     {
4249 	// No count, go to next tab page, wrap around end.
4250 	if (curtab->tp_next == NULL)
4251 	    tp = first_tabpage;
4252 	else
4253 	    tp = curtab->tp_next;
4254     }
4255     else if (n < 0)
4256     {
4257 	// "gT": go to previous tab page, wrap around end.  "N gT" repeats
4258 	// this N times.
4259 	ttp = curtab;
4260 	for (i = n; i < 0; ++i)
4261 	{
4262 	    for (tp = first_tabpage; tp->tp_next != ttp && tp->tp_next != NULL;
4263 		    tp = tp->tp_next)
4264 		;
4265 	    ttp = tp;
4266 	}
4267     }
4268     else if (n == 9999)
4269     {
4270 	// Go to last tab page.
4271 	for (tp = first_tabpage; tp->tp_next != NULL; tp = tp->tp_next)
4272 	    ;
4273     }
4274     else
4275     {
4276 	// Go to tab page "n".
4277 	tp = find_tabpage(n);
4278 	if (tp == NULL)
4279 	{
4280 	    beep_flush();
4281 	    return;
4282 	}
4283     }
4284 
4285     goto_tabpage_tp(tp, TRUE, TRUE);
4286 
4287 #ifdef FEAT_GUI_TABLINE
4288     if (gui_use_tabline())
4289 	gui_mch_set_curtab(tabpage_index(curtab));
4290 #endif
4291 }
4292 
4293 /*
4294  * Go to tabpage "tp".
4295  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4296  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4297  * Note: doesn't update the GUI tab.
4298  */
4299     void
4300 goto_tabpage_tp(
4301     tabpage_T	*tp,
4302     int		trigger_enter_autocmds,
4303     int		trigger_leave_autocmds)
4304 {
4305     // Don't repeat a message in another tab page.
4306     set_keep_msg(NULL, 0);
4307 
4308     if (tp != curtab && leave_tabpage(tp->tp_curwin->w_buffer,
4309 					trigger_leave_autocmds) == OK)
4310     {
4311 	if (valid_tabpage(tp))
4312 	    enter_tabpage(tp, curbuf, trigger_enter_autocmds,
4313 		    trigger_leave_autocmds);
4314 	else
4315 	    enter_tabpage(curtab, curbuf, trigger_enter_autocmds,
4316 		    trigger_leave_autocmds);
4317     }
4318 }
4319 
4320 /*
4321  * Go to the last accessed tab page, if there is one.
4322  * Return OK or FAIL
4323  */
4324     int
4325 goto_tabpage_lastused(void)
4326 {
4327     if (valid_tabpage(lastused_tabpage))
4328     {
4329 	goto_tabpage_tp(lastused_tabpage, TRUE, TRUE);
4330 	return OK;
4331     }
4332     return FAIL;
4333 }
4334 
4335 /*
4336  * Enter window "wp" in tab page "tp".
4337  * Also updates the GUI tab.
4338  */
4339     void
4340 goto_tabpage_win(tabpage_T *tp, win_T *wp)
4341 {
4342     goto_tabpage_tp(tp, TRUE, TRUE);
4343     if (curtab == tp && win_valid(wp))
4344     {
4345 	win_enter(wp, TRUE);
4346 # ifdef FEAT_GUI_TABLINE
4347 	if (gui_use_tabline())
4348 	    gui_mch_set_curtab(tabpage_index(curtab));
4349 # endif
4350     }
4351 }
4352 
4353 /*
4354  * Move the current tab page to after tab page "nr".
4355  */
4356     void
4357 tabpage_move(int nr)
4358 {
4359     int		n = 1;
4360     tabpage_T	*tp, *tp_dst;
4361 
4362     if (first_tabpage->tp_next == NULL)
4363 	return;
4364 
4365     for (tp = first_tabpage; tp->tp_next != NULL && n < nr; tp = tp->tp_next)
4366 	++n;
4367 
4368     if (tp == curtab || (nr > 0 && tp->tp_next != NULL
4369 						    && tp->tp_next == curtab))
4370 	return;
4371 
4372     tp_dst = tp;
4373 
4374     // Remove the current tab page from the list of tab pages.
4375     if (curtab == first_tabpage)
4376 	first_tabpage = curtab->tp_next;
4377     else
4378     {
4379 	FOR_ALL_TABPAGES(tp)
4380 	    if (tp->tp_next == curtab)
4381 		break;
4382 	if (tp == NULL)	// "cannot happen"
4383 	    return;
4384 	tp->tp_next = curtab->tp_next;
4385     }
4386 
4387     // Re-insert it at the specified position.
4388     if (nr <= 0)
4389     {
4390 	curtab->tp_next = first_tabpage;
4391 	first_tabpage = curtab;
4392     }
4393     else
4394     {
4395 	curtab->tp_next = tp_dst->tp_next;
4396 	tp_dst->tp_next = curtab;
4397     }
4398 
4399     // Need to redraw the tabline.  Tab page contents doesn't change.
4400     redraw_tabline = TRUE;
4401 }
4402 
4403 
4404 /*
4405  * Go to another window.
4406  * When jumping to another buffer, stop Visual mode.  Do this before
4407  * changing windows so we can yank the selection into the '*' register.
4408  * When jumping to another window on the same buffer, adjust its cursor
4409  * position to keep the same Visual area.
4410  */
4411     void
4412 win_goto(win_T *wp)
4413 {
4414 #ifdef FEAT_CONCEAL
4415     win_T	*owp = curwin;
4416 #endif
4417 
4418 #ifdef FEAT_PROP_POPUP
4419     if (ERROR_IF_ANY_POPUP_WINDOW)
4420 	return;
4421     if (popup_is_popup(wp))
4422     {
4423 	emsg(_("E366: Not allowed to enter a popup window"));
4424 	return;
4425     }
4426 #endif
4427     if (text_and_win_locked())
4428     {
4429 	beep_flush();
4430 	text_locked_msg();
4431 	return;
4432     }
4433     if (curbuf_locked())
4434 	return;
4435 
4436     if (wp->w_buffer != curbuf)
4437 	reset_VIsual_and_resel();
4438     else if (VIsual_active)
4439 	wp->w_cursor = curwin->w_cursor;
4440 
4441 #ifdef FEAT_GUI
4442     need_mouse_correct = TRUE;
4443 #endif
4444     win_enter(wp, TRUE);
4445 
4446 #ifdef FEAT_CONCEAL
4447     // Conceal cursor line in previous window, unconceal in current window.
4448     if (win_valid(owp) && owp->w_p_cole > 0 && !msg_scrolled)
4449 	redrawWinline(owp, owp->w_cursor.lnum);
4450     if (curwin->w_p_cole > 0 && !msg_scrolled)
4451 	need_cursor_line_redraw = TRUE;
4452 #endif
4453 }
4454 
4455 #if defined(FEAT_PERL) || defined(PROTO)
4456 /*
4457  * Find window number "winnr" (counting top to bottom).
4458  */
4459     win_T *
4460 win_find_nr(int winnr)
4461 {
4462     win_T	*wp;
4463 
4464     FOR_ALL_WINDOWS(wp)
4465 	if (--winnr == 0)
4466 	    break;
4467     return wp;
4468 }
4469 #endif
4470 
4471 #if ((defined(FEAT_PYTHON) || defined(FEAT_PYTHON3))) || defined(PROTO)
4472 /*
4473  * Find the tabpage for window "win".
4474  */
4475     tabpage_T *
4476 win_find_tabpage(win_T *win)
4477 {
4478     win_T	*wp;
4479     tabpage_T	*tp;
4480 
4481     FOR_ALL_TAB_WINDOWS(tp, wp)
4482 	    if (wp == win)
4483 		return tp;
4484     return NULL;
4485 }
4486 #endif
4487 
4488 /*
4489  * Get the above or below neighbor window of the specified window.
4490  *   up - TRUE for the above neighbor
4491  *   count - nth neighbor window
4492  * Returns the specified window if the neighbor is not found.
4493  */
4494     win_T *
4495 win_vert_neighbor(tabpage_T *tp, win_T *wp, int up, long count)
4496 {
4497     frame_T	*fr;
4498     frame_T	*nfr;
4499     frame_T	*foundfr;
4500 
4501 #ifdef FEAT_PROP_POPUP
4502     if (popup_is_popup(wp))
4503 	// popups don't have neighbors.
4504 	return NULL;
4505 #endif
4506     foundfr = wp->w_frame;
4507     while (count--)
4508     {
4509 	/*
4510 	 * First go upwards in the tree of frames until we find a upwards or
4511 	 * downwards neighbor.
4512 	 */
4513 	fr = foundfr;
4514 	for (;;)
4515 	{
4516 	    if (fr == tp->tp_topframe)
4517 		goto end;
4518 	    if (up)
4519 		nfr = fr->fr_prev;
4520 	    else
4521 		nfr = fr->fr_next;
4522 	    if (fr->fr_parent->fr_layout == FR_COL && nfr != NULL)
4523 		break;
4524 	    fr = fr->fr_parent;
4525 	}
4526 
4527 	/*
4528 	 * Now go downwards to find the bottom or top frame in it.
4529 	 */
4530 	for (;;)
4531 	{
4532 	    if (nfr->fr_layout == FR_LEAF)
4533 	    {
4534 		foundfr = nfr;
4535 		break;
4536 	    }
4537 	    fr = nfr->fr_child;
4538 	    if (nfr->fr_layout == FR_ROW)
4539 	    {
4540 		// Find the frame at the cursor row.
4541 		while (fr->fr_next != NULL
4542 			&& frame2win(fr)->w_wincol + fr->fr_width
4543 					 <= wp->w_wincol + wp->w_wcol)
4544 		    fr = fr->fr_next;
4545 	    }
4546 	    if (nfr->fr_layout == FR_COL && up)
4547 		while (fr->fr_next != NULL)
4548 		    fr = fr->fr_next;
4549 	    nfr = fr;
4550 	}
4551     }
4552 end:
4553     return foundfr != NULL ? foundfr->fr_win : NULL;
4554 }
4555 
4556 /*
4557  * Move to window above or below "count" times.
4558  */
4559     static void
4560 win_goto_ver(
4561     int		up,		// TRUE to go to win above
4562     long	count)
4563 {
4564     win_T	*win;
4565 
4566 #ifdef FEAT_PROP_POPUP
4567     if (ERROR_IF_TERM_POPUP_WINDOW)
4568 	return;
4569 #endif
4570     win = win_vert_neighbor(curtab, curwin, up, count);
4571     if (win != NULL)
4572 	win_goto(win);
4573 }
4574 
4575 /*
4576  * Get the left or right neighbor window of the specified window.
4577  *   left - TRUE for the left neighbor
4578  *   count - nth neighbor window
4579  * Returns the specified window if the neighbor is not found.
4580  */
4581     win_T *
4582 win_horz_neighbor(tabpage_T *tp, win_T *wp, int left, long count)
4583 {
4584     frame_T	*fr;
4585     frame_T	*nfr;
4586     frame_T	*foundfr;
4587 
4588 #ifdef FEAT_PROP_POPUP
4589     if (popup_is_popup(wp))
4590 	// popups don't have neighbors.
4591 	return NULL;
4592 #endif
4593     foundfr = wp->w_frame;
4594     while (count--)
4595     {
4596 	/*
4597 	 * First go upwards in the tree of frames until we find a left or
4598 	 * right neighbor.
4599 	 */
4600 	fr = foundfr;
4601 	for (;;)
4602 	{
4603 	    if (fr == tp->tp_topframe)
4604 		goto end;
4605 	    if (left)
4606 		nfr = fr->fr_prev;
4607 	    else
4608 		nfr = fr->fr_next;
4609 	    if (fr->fr_parent->fr_layout == FR_ROW && nfr != NULL)
4610 		break;
4611 	    fr = fr->fr_parent;
4612 	}
4613 
4614 	/*
4615 	 * Now go downwards to find the leftmost or rightmost frame in it.
4616 	 */
4617 	for (;;)
4618 	{
4619 	    if (nfr->fr_layout == FR_LEAF)
4620 	    {
4621 		foundfr = nfr;
4622 		break;
4623 	    }
4624 	    fr = nfr->fr_child;
4625 	    if (nfr->fr_layout == FR_COL)
4626 	    {
4627 		// Find the frame at the cursor row.
4628 		while (fr->fr_next != NULL
4629 			&& frame2win(fr)->w_winrow + fr->fr_height
4630 					 <= wp->w_winrow + wp->w_wrow)
4631 		    fr = fr->fr_next;
4632 	    }
4633 	    if (nfr->fr_layout == FR_ROW && left)
4634 		while (fr->fr_next != NULL)
4635 		    fr = fr->fr_next;
4636 	    nfr = fr;
4637 	}
4638     }
4639 end:
4640     return foundfr != NULL ? foundfr->fr_win : NULL;
4641 }
4642 
4643 /*
4644  * Move to left or right window.
4645  */
4646     static void
4647 win_goto_hor(
4648     int		left,		// TRUE to go to left win
4649     long	count)
4650 {
4651     win_T	*win;
4652 
4653 #ifdef FEAT_PROP_POPUP
4654     if (ERROR_IF_TERM_POPUP_WINDOW)
4655 	return;
4656 #endif
4657     win = win_horz_neighbor(curtab, curwin, left, count);
4658     if (win != NULL)
4659 	win_goto(win);
4660 }
4661 
4662 /*
4663  * Make window "wp" the current window.
4664  */
4665     void
4666 win_enter(win_T *wp, int undo_sync)
4667 {
4668     win_enter_ext(wp, undo_sync, FALSE, FALSE, TRUE, TRUE);
4669 }
4670 
4671 /*
4672  * Make window wp the current window.
4673  * Can be called with "curwin_invalid" TRUE, which means that curwin has just
4674  * been closed and isn't valid.
4675  */
4676     static void
4677 win_enter_ext(
4678     win_T	*wp,
4679     int		undo_sync,
4680     int		curwin_invalid,
4681     int		trigger_new_autocmds,
4682     int		trigger_enter_autocmds,
4683     int		trigger_leave_autocmds)
4684 {
4685     int		other_buffer = FALSE;
4686 
4687     if (wp == curwin && !curwin_invalid)	// nothing to do
4688 	return;
4689 
4690 #ifdef FEAT_JOB_CHANNEL
4691     if (!curwin_invalid)
4692 	leaving_window(curwin);
4693 #endif
4694 
4695     if (!curwin_invalid && trigger_leave_autocmds)
4696     {
4697 	/*
4698 	 * Be careful: If autocommands delete the window, return now.
4699 	 */
4700 	if (wp->w_buffer != curbuf)
4701 	{
4702 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4703 	    other_buffer = TRUE;
4704 	    if (!win_valid(wp))
4705 		return;
4706 	}
4707 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4708 	if (!win_valid(wp))
4709 	    return;
4710 #ifdef FEAT_EVAL
4711 	// autocmds may abort script processing
4712 	if (aborting())
4713 	    return;
4714 #endif
4715     }
4716 
4717     // sync undo before leaving the current buffer
4718     if (undo_sync && curbuf != wp->w_buffer)
4719 	u_sync(FALSE);
4720 
4721     // Might need to scroll the old window before switching, e.g., when the
4722     // cursor was moved.
4723     update_topline();
4724 
4725     // may have to copy the buffer options when 'cpo' contains 'S'
4726     if (wp->w_buffer != curbuf)
4727 	buf_copy_options(wp->w_buffer, BCO_ENTER | BCO_NOHELP);
4728     if (!curwin_invalid)
4729     {
4730 	prevwin = curwin;	// remember for CTRL-W p
4731 	curwin->w_redr_status = TRUE;
4732     }
4733     curwin = wp;
4734     curbuf = wp->w_buffer;
4735     check_cursor();
4736     if (!virtual_active())
4737 	curwin->w_cursor.coladd = 0;
4738     changed_line_abv_curs();	// assume cursor position needs updating
4739 
4740     if (curwin->w_localdir != NULL || curtab->tp_localdir != NULL)
4741     {
4742 	char_u	*dirname;
4743 
4744 	// Window or tab has a local directory: Save current directory as
4745 	// global directory (unless that was done already) and change to the
4746 	// local directory.
4747 	if (globaldir == NULL)
4748 	{
4749 	    char_u	cwd[MAXPATHL];
4750 
4751 	    if (mch_dirname(cwd, MAXPATHL) == OK)
4752 		globaldir = vim_strsave(cwd);
4753 	}
4754 	if (curwin->w_localdir != NULL)
4755 	    dirname = curwin->w_localdir;
4756 	else
4757 	    dirname = curtab->tp_localdir;
4758 
4759 	if (mch_chdir((char *)dirname) == 0)
4760 	    shorten_fnames(TRUE);
4761     }
4762     else if (globaldir != NULL)
4763     {
4764 	// Window doesn't have a local directory and we are not in the global
4765 	// directory: Change to the global directory.
4766 	vim_ignored = mch_chdir((char *)globaldir);
4767 	VIM_CLEAR(globaldir);
4768 	shorten_fnames(TRUE);
4769     }
4770 
4771 #ifdef FEAT_JOB_CHANNEL
4772     entering_window(curwin);
4773 #endif
4774     // Careful: autocommands may close the window and make "wp" invalid
4775     if (trigger_new_autocmds)
4776 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
4777     if (trigger_enter_autocmds)
4778     {
4779 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
4780 	if (other_buffer)
4781 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4782     }
4783 
4784 #ifdef FEAT_TITLE
4785     maketitle();
4786 #endif
4787     curwin->w_redr_status = TRUE;
4788 #ifdef FEAT_TERMINAL
4789     if (bt_terminal(curwin->w_buffer))
4790 	// terminal is likely in another mode
4791 	redraw_mode = TRUE;
4792 #endif
4793     redraw_tabline = TRUE;
4794     if (restart_edit)
4795 	redraw_later(VALID);	// causes status line redraw
4796 
4797     // set window height to desired minimal value
4798     if (curwin->w_height < p_wh && !curwin->w_p_wfh
4799 #ifdef FEAT_PROP_POPUP
4800 	    && !popup_is_popup(curwin)
4801 #endif
4802 	    )
4803 	win_setheight((int)p_wh);
4804     else if (curwin->w_height == 0)
4805 	win_setheight(1);
4806 
4807     // set window width to desired minimal value
4808     if (curwin->w_width < p_wiw && !curwin->w_p_wfw)
4809 	win_setwidth((int)p_wiw);
4810 
4811     setmouse();			// in case jumped to/from help buffer
4812 
4813     // Change directories when the 'acd' option is set.
4814     DO_AUTOCHDIR;
4815 }
4816 
4817 
4818 /*
4819  * Jump to the first open window that contains buffer "buf", if one exists.
4820  * Returns a pointer to the window found, otherwise NULL.
4821  */
4822     win_T *
4823 buf_jump_open_win(buf_T *buf)
4824 {
4825     win_T	*wp = NULL;
4826 
4827     if (curwin->w_buffer == buf)
4828 	wp = curwin;
4829     else
4830 	FOR_ALL_WINDOWS(wp)
4831 	    if (wp->w_buffer == buf)
4832 		break;
4833     if (wp != NULL)
4834 	win_enter(wp, FALSE);
4835     return wp;
4836 }
4837 
4838 /*
4839  * Jump to the first open window in any tab page that contains buffer "buf",
4840  * if one exists.
4841  * Returns a pointer to the window found, otherwise NULL.
4842  */
4843     win_T *
4844 buf_jump_open_tab(buf_T *buf)
4845 {
4846     win_T	*wp = buf_jump_open_win(buf);
4847     tabpage_T	*tp;
4848 
4849     if (wp != NULL)
4850 	return wp;
4851 
4852     FOR_ALL_TABPAGES(tp)
4853 	if (tp != curtab)
4854 	{
4855 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
4856 		if (wp->w_buffer == buf)
4857 		    break;
4858 	    if (wp != NULL)
4859 	    {
4860 		goto_tabpage_win(tp, wp);
4861 		if (curwin != wp)
4862 		    wp = NULL;	// something went wrong
4863 		break;
4864 	    }
4865 	}
4866     return wp;
4867 }
4868 
4869 static int last_win_id = LOWEST_WIN_ID - 1;
4870 
4871 /*
4872  * Allocate a window structure and link it in the window list when "hidden" is
4873  * FALSE.
4874  */
4875     static win_T *
4876 win_alloc(win_T *after UNUSED, int hidden UNUSED)
4877 {
4878     win_T	*new_wp;
4879 
4880     /*
4881      * allocate window structure and linesizes arrays
4882      */
4883     new_wp = ALLOC_CLEAR_ONE(win_T);
4884     if (new_wp == NULL)
4885 	return NULL;
4886 
4887     if (win_alloc_lines(new_wp) == FAIL)
4888     {
4889 	vim_free(new_wp);
4890 	return NULL;
4891     }
4892 
4893     new_wp->w_id = ++last_win_id;
4894 
4895 #ifdef FEAT_EVAL
4896     // init w: variables
4897     new_wp->w_vars = dict_alloc();
4898     if (new_wp->w_vars == NULL)
4899     {
4900 	win_free_lsize(new_wp);
4901 	vim_free(new_wp);
4902 	return NULL;
4903     }
4904     init_var_dict(new_wp->w_vars, &new_wp->w_winvar, VAR_SCOPE);
4905 #endif
4906 
4907     // Don't execute autocommands while the window is not properly
4908     // initialized yet.  gui_create_scrollbar() may trigger a FocusGained
4909     // event.
4910     block_autocmds();
4911 
4912     /*
4913      * link the window in the window list
4914      */
4915     if (!hidden)
4916 	win_append(after, new_wp);
4917     new_wp->w_wincol = 0;
4918     new_wp->w_width = Columns;
4919 
4920     // position the display and the cursor at the top of the file.
4921     new_wp->w_topline = 1;
4922 #ifdef FEAT_DIFF
4923     new_wp->w_topfill = 0;
4924 #endif
4925     new_wp->w_botline = 2;
4926     new_wp->w_cursor.lnum = 1;
4927     new_wp->w_scbind_pos = 1;
4928 
4929     // use global option value for global-local options
4930     new_wp->w_p_so = -1;
4931     new_wp->w_p_siso = -1;
4932 
4933     // We won't calculate w_fraction until resizing the window
4934     new_wp->w_fraction = 0;
4935     new_wp->w_prev_fraction_row = -1;
4936 
4937 #ifdef FEAT_GUI
4938     if (gui.in_use)
4939     {
4940 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_LEFT],
4941 		SBAR_LEFT, new_wp);
4942 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_RIGHT],
4943 		SBAR_RIGHT, new_wp);
4944     }
4945 #endif
4946 #ifdef FEAT_FOLDING
4947     foldInitWin(new_wp);
4948 #endif
4949     unblock_autocmds();
4950 #ifdef FEAT_SEARCH_EXTRA
4951     new_wp->w_match_head = NULL;
4952     new_wp->w_next_match_id = 4;
4953 #endif
4954     return new_wp;
4955 }
4956 
4957 /*
4958  * Remove window 'wp' from the window list and free the structure.
4959  */
4960     static void
4961 win_free(
4962     win_T	*wp,
4963     tabpage_T	*tp)		// tab page "win" is in, NULL for current
4964 {
4965     int		i;
4966     buf_T	*buf;
4967     wininfo_T	*wip;
4968 
4969 #ifdef FEAT_FOLDING
4970     clearFolding(wp);
4971 #endif
4972 
4973     // reduce the reference count to the argument list.
4974     alist_unlink(wp->w_alist);
4975 
4976     // Don't execute autocommands while the window is halfway being deleted.
4977     // gui_mch_destroy_scrollbar() may trigger a FocusGained event.
4978     block_autocmds();
4979 
4980 #ifdef FEAT_LUA
4981     lua_window_free(wp);
4982 #endif
4983 
4984 #ifdef FEAT_MZSCHEME
4985     mzscheme_window_free(wp);
4986 #endif
4987 
4988 #ifdef FEAT_PERL
4989     perl_win_free(wp);
4990 #endif
4991 
4992 #ifdef FEAT_PYTHON
4993     python_window_free(wp);
4994 #endif
4995 
4996 #ifdef FEAT_PYTHON3
4997     python3_window_free(wp);
4998 #endif
4999 
5000 #ifdef FEAT_TCL
5001     tcl_window_free(wp);
5002 #endif
5003 
5004 #ifdef FEAT_RUBY
5005     ruby_window_free(wp);
5006 #endif
5007 
5008     clear_winopt(&wp->w_onebuf_opt);
5009     clear_winopt(&wp->w_allbuf_opt);
5010 
5011 #ifdef FEAT_EVAL
5012     vars_clear(&wp->w_vars->dv_hashtab);	// free all w: variables
5013     hash_init(&wp->w_vars->dv_hashtab);
5014     unref_var_dict(wp->w_vars);
5015 #endif
5016 
5017     {
5018 	tabpage_T	*ttp;
5019 
5020 	if (prevwin == wp)
5021 	    prevwin = NULL;
5022 	FOR_ALL_TABPAGES(ttp)
5023 	    if (ttp->tp_prevwin == wp)
5024 		ttp->tp_prevwin = NULL;
5025     }
5026     win_free_lsize(wp);
5027 
5028     for (i = 0; i < wp->w_tagstacklen; ++i)
5029     {
5030 	vim_free(wp->w_tagstack[i].tagname);
5031 	vim_free(wp->w_tagstack[i].user_data);
5032     }
5033     vim_free(wp->w_localdir);
5034     vim_free(wp->w_prevdir);
5035 
5036     // Remove the window from the b_wininfo lists, it may happen that the
5037     // freed memory is re-used for another window.
5038     FOR_ALL_BUFFERS(buf)
5039 	FOR_ALL_BUF_WININFO(buf, wip)
5040 	    if (wip->wi_win == wp)
5041 	    {
5042 		wininfo_T	*wip2;
5043 
5044 		// If there already is an entry with "wi_win" set to NULL it
5045 		// must be removed, it would never be used.
5046 		for (wip2 = buf->b_wininfo; wip2 != NULL; wip2 = wip2->wi_next)
5047 		    if (wip2->wi_win == NULL)
5048 		    {
5049 			if (wip2->wi_next != NULL)
5050 			    wip2->wi_next->wi_prev = wip2->wi_prev;
5051 			if (wip2->wi_prev == NULL)
5052 			    buf->b_wininfo = wip2->wi_next;
5053 			else
5054 			    wip2->wi_prev->wi_next = wip2->wi_next;
5055 			free_wininfo(wip2);
5056 			break;
5057 		    }
5058 
5059 		wip->wi_win = NULL;
5060 	    }
5061 
5062 #ifdef FEAT_SEARCH_EXTRA
5063     clear_matches(wp);
5064 #endif
5065 
5066 #ifdef FEAT_JUMPLIST
5067     free_jumplist(wp);
5068 #endif
5069 
5070 #ifdef FEAT_QUICKFIX
5071     qf_free_all(wp);
5072 #endif
5073 
5074 #ifdef FEAT_GUI
5075     if (gui.in_use)
5076     {
5077 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_LEFT]);
5078 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_RIGHT]);
5079     }
5080 #endif // FEAT_GUI
5081 
5082 #ifdef FEAT_MENU
5083     remove_winbar(wp);
5084 #endif
5085 #ifdef FEAT_PROP_POPUP
5086     free_callback(&wp->w_close_cb);
5087     free_callback(&wp->w_filter_cb);
5088     for (i = 0; i < 4; ++i)
5089 	VIM_CLEAR(wp->w_border_highlight[i]);
5090     vim_free(wp->w_scrollbar_highlight);
5091     vim_free(wp->w_thumb_highlight);
5092     vim_free(wp->w_popup_title);
5093     list_unref(wp->w_popup_mask);
5094     vim_free(wp->w_popup_mask_cells);
5095 #endif
5096 
5097 #ifdef FEAT_SYN_HL
5098     vim_free(wp->w_p_cc_cols);
5099 #endif
5100 
5101     if (win_valid_any_tab(wp))
5102 	win_remove(wp, tp);
5103     if (autocmd_busy)
5104     {
5105 	wp->w_next = au_pending_free_win;
5106 	au_pending_free_win = wp;
5107     }
5108     else
5109 	vim_free(wp);
5110 
5111     unblock_autocmds();
5112 }
5113 
5114 /*
5115  * Return TRUE if "wp" is not in the list of windows: the autocmd window or a
5116  * popup window.
5117  */
5118     static int
5119 win_unlisted(win_T *wp)
5120 {
5121     return wp == aucmd_win || WIN_IS_POPUP(wp);
5122 }
5123 
5124 #if defined(FEAT_PROP_POPUP) || defined(PROTO)
5125 /*
5126  * Free a popup window.  This does not take the window out of the window list
5127  * and assumes there is only one toplevel frame, no split.
5128  */
5129     void
5130 win_free_popup(win_T *win)
5131 {
5132     if (bt_popup(win->w_buffer))
5133 	win_close_buffer(win, DOBUF_WIPE_REUSE, FALSE);
5134     else
5135 	close_buffer(win, win->w_buffer, 0, FALSE, FALSE);
5136 # if defined(FEAT_TIMERS)
5137     if (win->w_popup_timer != NULL)
5138 	stop_timer(win->w_popup_timer);
5139 # endif
5140     vim_free(win->w_frame);
5141     win_free(win, NULL);
5142 }
5143 #endif
5144 
5145 /*
5146  * Append window "wp" in the window list after window "after".
5147  */
5148     static void
5149 win_append(win_T *after, win_T *wp)
5150 {
5151     win_T	*before;
5152 
5153     if (after == NULL)	    // after NULL is in front of the first
5154 	before = firstwin;
5155     else
5156 	before = after->w_next;
5157 
5158     wp->w_next = before;
5159     wp->w_prev = after;
5160     if (after == NULL)
5161 	firstwin = wp;
5162     else
5163 	after->w_next = wp;
5164     if (before == NULL)
5165 	lastwin = wp;
5166     else
5167 	before->w_prev = wp;
5168 }
5169 
5170 /*
5171  * Remove a window from the window list.
5172  */
5173     void
5174 win_remove(
5175     win_T	*wp,
5176     tabpage_T	*tp)		// tab page "win" is in, NULL for current
5177 {
5178     if (wp->w_prev != NULL)
5179 	wp->w_prev->w_next = wp->w_next;
5180     else if (tp == NULL)
5181 	firstwin = curtab->tp_firstwin = wp->w_next;
5182     else
5183 	tp->tp_firstwin = wp->w_next;
5184 
5185     if (wp->w_next != NULL)
5186 	wp->w_next->w_prev = wp->w_prev;
5187     else if (tp == NULL)
5188 	lastwin = curtab->tp_lastwin = wp->w_prev;
5189     else
5190 	tp->tp_lastwin = wp->w_prev;
5191 }
5192 
5193 /*
5194  * Append frame "frp" in a frame list after frame "after".
5195  */
5196     static void
5197 frame_append(frame_T *after, frame_T *frp)
5198 {
5199     frp->fr_next = after->fr_next;
5200     after->fr_next = frp;
5201     if (frp->fr_next != NULL)
5202 	frp->fr_next->fr_prev = frp;
5203     frp->fr_prev = after;
5204 }
5205 
5206 /*
5207  * Insert frame "frp" in a frame list before frame "before".
5208  */
5209     static void
5210 frame_insert(frame_T *before, frame_T *frp)
5211 {
5212     frp->fr_next = before;
5213     frp->fr_prev = before->fr_prev;
5214     before->fr_prev = frp;
5215     if (frp->fr_prev != NULL)
5216 	frp->fr_prev->fr_next = frp;
5217     else
5218 	frp->fr_parent->fr_child = frp;
5219 }
5220 
5221 /*
5222  * Remove a frame from a frame list.
5223  */
5224     static void
5225 frame_remove(frame_T *frp)
5226 {
5227     if (frp->fr_prev != NULL)
5228 	frp->fr_prev->fr_next = frp->fr_next;
5229     else
5230     {
5231 	frp->fr_parent->fr_child = frp->fr_next;
5232 	// special case: topframe->fr_child == frp
5233 	if (topframe->fr_child == frp)
5234 	    topframe->fr_child = frp->fr_next;
5235     }
5236     if (frp->fr_next != NULL)
5237 	frp->fr_next->fr_prev = frp->fr_prev;
5238 }
5239 
5240 /*
5241  * Allocate w_lines[] for window "wp".
5242  * Return FAIL for failure, OK for success.
5243  */
5244     int
5245 win_alloc_lines(win_T *wp)
5246 {
5247     wp->w_lines_valid = 0;
5248     wp->w_lines = ALLOC_CLEAR_MULT(wline_T, Rows );
5249     if (wp->w_lines == NULL)
5250 	return FAIL;
5251     return OK;
5252 }
5253 
5254 /*
5255  * free lsize arrays for a window
5256  */
5257     void
5258 win_free_lsize(win_T *wp)
5259 {
5260     // TODO: why would wp be NULL here?
5261     if (wp != NULL)
5262 	VIM_CLEAR(wp->w_lines);
5263 }
5264 
5265 /*
5266  * Called from win_new_shellsize() after Rows changed.
5267  * This only does the current tab page, others must be done when made active.
5268  */
5269     void
5270 shell_new_rows(void)
5271 {
5272     int		h = (int)ROWS_AVAIL;
5273 
5274     if (firstwin == NULL)	// not initialized yet
5275 	return;
5276     if (h < frame_minheight(topframe, NULL))
5277 	h = frame_minheight(topframe, NULL);
5278 
5279     // First try setting the heights of windows with 'winfixheight'.  If
5280     // that doesn't result in the right height, forget about that option.
5281     frame_new_height(topframe, h, FALSE, TRUE);
5282     if (!frame_check_height(topframe, h))
5283 	frame_new_height(topframe, h, FALSE, FALSE);
5284 
5285     (void)win_comp_pos();		// recompute w_winrow and w_wincol
5286     compute_cmdrow();
5287     curtab->tp_ch_used = p_ch;
5288 
5289 #if 0
5290     // Disabled: don't want making the screen smaller make a window larger.
5291     if (p_ea)
5292 	win_equal(curwin, FALSE, 'v');
5293 #endif
5294 }
5295 
5296 /*
5297  * Called from win_new_shellsize() after Columns changed.
5298  */
5299     void
5300 shell_new_columns(void)
5301 {
5302     if (firstwin == NULL)	// not initialized yet
5303 	return;
5304 
5305     // First try setting the widths of windows with 'winfixwidth'.  If that
5306     // doesn't result in the right width, forget about that option.
5307     frame_new_width(topframe, (int)Columns, FALSE, TRUE);
5308     if (!frame_check_width(topframe, Columns))
5309 	frame_new_width(topframe, (int)Columns, FALSE, FALSE);
5310 
5311     (void)win_comp_pos();		// recompute w_winrow and w_wincol
5312 #if 0
5313     // Disabled: don't want making the screen smaller make a window larger.
5314     if (p_ea)
5315 	win_equal(curwin, FALSE, 'h');
5316 #endif
5317 }
5318 
5319 #if defined(FEAT_CMDWIN) || defined(PROTO)
5320 /*
5321  * Save the size of all windows in "gap".
5322  */
5323     void
5324 win_size_save(garray_T *gap)
5325 
5326 {
5327     win_T	*wp;
5328 
5329     ga_init2(gap, (int)sizeof(int), 1);
5330     if (ga_grow(gap, win_count() * 2 + 1) == OK)
5331     {
5332 	// first entry is value of 'lines'
5333 	((int *)gap->ga_data)[gap->ga_len++] = Rows;
5334 
5335 	FOR_ALL_WINDOWS(wp)
5336 	{
5337 	    ((int *)gap->ga_data)[gap->ga_len++] =
5338 					       wp->w_width + wp->w_vsep_width;
5339 	    ((int *)gap->ga_data)[gap->ga_len++] = wp->w_height;
5340 	}
5341     }
5342 }
5343 
5344 /*
5345  * Restore window sizes, but only if the number of windows is still the same
5346  * and 'lines' didn't change.
5347  * Does not free the growarray.
5348  */
5349     void
5350 win_size_restore(garray_T *gap)
5351 {
5352     win_T	*wp;
5353     int		i, j;
5354 
5355     if (win_count() * 2 + 1 == gap->ga_len
5356 	    && ((int *)gap->ga_data)[0] == Rows)
5357     {
5358 	// The order matters, because frames contain other frames, but it's
5359 	// difficult to get right. The easy way out is to do it twice.
5360 	for (j = 0; j < 2; ++j)
5361 	{
5362 	    i = 1;
5363 	    FOR_ALL_WINDOWS(wp)
5364 	    {
5365 		frame_setwidth(wp->w_frame, ((int *)gap->ga_data)[i++]);
5366 		win_setheight_win(((int *)gap->ga_data)[i++], wp);
5367 	    }
5368 	}
5369 	// recompute the window positions
5370 	(void)win_comp_pos();
5371     }
5372 }
5373 #endif // FEAT_CMDWIN
5374 
5375 /*
5376  * Update the position for all windows, using the width and height of the
5377  * frames.
5378  * Returns the row just after the last window.
5379  */
5380     int
5381 win_comp_pos(void)
5382 {
5383     int		row = tabline_height();
5384     int		col = 0;
5385 
5386     frame_comp_pos(topframe, &row, &col);
5387     return row;
5388 }
5389 
5390 /*
5391  * Update the position of the windows in frame "topfrp", using the width and
5392  * height of the frames.
5393  * "*row" and "*col" are the top-left position of the frame.  They are updated
5394  * to the bottom-right position plus one.
5395  */
5396     static void
5397 frame_comp_pos(frame_T *topfrp, int *row, int *col)
5398 {
5399     win_T	*wp;
5400     frame_T	*frp;
5401     int		startcol;
5402     int		startrow;
5403     int		h;
5404 
5405     wp = topfrp->fr_win;
5406     if (wp != NULL)
5407     {
5408 	if (wp->w_winrow != *row || wp->w_wincol != *col)
5409 	{
5410 	    // position changed, redraw
5411 	    wp->w_winrow = *row;
5412 	    wp->w_wincol = *col;
5413 	    redraw_win_later(wp, NOT_VALID);
5414 	    wp->w_redr_status = TRUE;
5415 	}
5416 	// WinBar will not show if the window height is zero
5417 	h = VISIBLE_HEIGHT(wp) + wp->w_status_height;
5418 	*row += h > topfrp->fr_height ? topfrp->fr_height : h;
5419 	*col += wp->w_width + wp->w_vsep_width;
5420     }
5421     else
5422     {
5423 	startrow = *row;
5424 	startcol = *col;
5425 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
5426 	{
5427 	    if (topfrp->fr_layout == FR_ROW)
5428 		*row = startrow;	// all frames are at the same row
5429 	    else
5430 		*col = startcol;	// all frames are at the same col
5431 	    frame_comp_pos(frp, row, col);
5432 	}
5433     }
5434 }
5435 
5436 /*
5437  * Set current window height and take care of repositioning other windows to
5438  * fit around it.
5439  */
5440     void
5441 win_setheight(int height)
5442 {
5443     win_setheight_win(height, curwin);
5444 }
5445 
5446 /*
5447  * Set the window height of window "win" and take care of repositioning other
5448  * windows to fit around it.
5449  */
5450     void
5451 win_setheight_win(int height, win_T *win)
5452 {
5453     int		row;
5454 
5455     if (win == curwin)
5456     {
5457 	// Always keep current window at least one line high, even when
5458 	// 'winminheight' is zero.
5459 	if (height < p_wmh)
5460 	    height = p_wmh;
5461 	if (height == 0)
5462 	    height = 1;
5463 	height += WINBAR_HEIGHT(curwin);
5464     }
5465 
5466     frame_setheight(win->w_frame, height + win->w_status_height);
5467 
5468     // recompute the window positions
5469     row = win_comp_pos();
5470 
5471     /*
5472      * If there is extra space created between the last window and the command
5473      * line, clear it.
5474      */
5475     if (full_screen && msg_scrolled == 0 && row < cmdline_row)
5476 	screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5477     cmdline_row = row;
5478     msg_row = row;
5479     msg_col = 0;
5480 
5481     redraw_all_later(NOT_VALID);
5482 }
5483 
5484 /*
5485  * Set the height of a frame to "height" and take care that all frames and
5486  * windows inside it are resized.  Also resize frames on the left and right if
5487  * the are in the same FR_ROW frame.
5488  *
5489  * Strategy:
5490  * If the frame is part of a FR_COL frame, try fitting the frame in that
5491  * frame.  If that doesn't work (the FR_COL frame is too small), recursively
5492  * go to containing frames to resize them and make room.
5493  * If the frame is part of a FR_ROW frame, all frames must be resized as well.
5494  * Check for the minimal height of the FR_ROW frame.
5495  * At the top level we can also use change the command line height.
5496  */
5497     static void
5498 frame_setheight(frame_T *curfrp, int height)
5499 {
5500     int		room;		// total number of lines available
5501     int		take;		// number of lines taken from other windows
5502     int		room_cmdline;	// lines available from cmdline
5503     int		run;
5504     frame_T	*frp;
5505     int		h;
5506     int		room_reserved;
5507 
5508     // If the height already is the desired value, nothing to do.
5509     if (curfrp->fr_height == height)
5510 	return;
5511 
5512     if (curfrp->fr_parent == NULL)
5513     {
5514 	// topframe: can only change the command line
5515 	if (height > ROWS_AVAIL)
5516 	    height = ROWS_AVAIL;
5517 	if (height > 0)
5518 	    frame_new_height(curfrp, height, FALSE, FALSE);
5519     }
5520     else if (curfrp->fr_parent->fr_layout == FR_ROW)
5521     {
5522 	// Row of frames: Also need to resize frames left and right of this
5523 	// one.  First check for the minimal height of these.
5524 	h = frame_minheight(curfrp->fr_parent, NULL);
5525 	if (height < h)
5526 	    height = h;
5527 	frame_setheight(curfrp->fr_parent, height);
5528     }
5529     else
5530     {
5531 	/*
5532 	 * Column of frames: try to change only frames in this column.
5533 	 */
5534 	/*
5535 	 * Do this twice:
5536 	 * 1: compute room available, if it's not enough try resizing the
5537 	 *    containing frame.
5538 	 * 2: compute the room available and adjust the height to it.
5539 	 * Try not to reduce the height of a window with 'winfixheight' set.
5540 	 */
5541 	for (run = 1; run <= 2; ++run)
5542 	{
5543 	    room = 0;
5544 	    room_reserved = 0;
5545 	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
5546 	    {
5547 		if (frp != curfrp
5548 			&& frp->fr_win != NULL
5549 			&& frp->fr_win->w_p_wfh)
5550 		    room_reserved += frp->fr_height;
5551 		room += frp->fr_height;
5552 		if (frp != curfrp)
5553 		    room -= frame_minheight(frp, NULL);
5554 	    }
5555 	    if (curfrp->fr_width != Columns)
5556 		room_cmdline = 0;
5557 	    else
5558 	    {
5559 		room_cmdline = Rows - p_ch - (lastwin->w_winrow
5560 						+ VISIBLE_HEIGHT(lastwin)
5561 						+ lastwin->w_status_height);
5562 		if (room_cmdline < 0)
5563 		    room_cmdline = 0;
5564 	    }
5565 
5566 	    if (height <= room + room_cmdline)
5567 		break;
5568 	    if (run == 2 || curfrp->fr_width == Columns)
5569 	    {
5570 		if (height > room + room_cmdline)
5571 		    height = room + room_cmdline;
5572 		break;
5573 	    }
5574 	    frame_setheight(curfrp->fr_parent, height
5575 		+ frame_minheight(curfrp->fr_parent, NOWIN) - (int)p_wmh - 1);
5576 	}
5577 
5578 	/*
5579 	 * Compute the number of lines we will take from others frames (can be
5580 	 * negative!).
5581 	 */
5582 	take = height - curfrp->fr_height;
5583 
5584 	// If there is not enough room, also reduce the height of a window
5585 	// with 'winfixheight' set.
5586 	if (height > room + room_cmdline - room_reserved)
5587 	    room_reserved = room + room_cmdline - height;
5588 	// If there is only a 'winfixheight' window and making the
5589 	// window smaller, need to make the other window taller.
5590 	if (take < 0 && room - curfrp->fr_height < room_reserved)
5591 	    room_reserved = 0;
5592 
5593 	if (take > 0 && room_cmdline > 0)
5594 	{
5595 	    // use lines from cmdline first
5596 	    if (take < room_cmdline)
5597 		room_cmdline = take;
5598 	    take -= room_cmdline;
5599 	    topframe->fr_height += room_cmdline;
5600 	}
5601 
5602 	/*
5603 	 * set the current frame to the new height
5604 	 */
5605 	frame_new_height(curfrp, height, FALSE, FALSE);
5606 
5607 	/*
5608 	 * First take lines from the frames after the current frame.  If
5609 	 * that is not enough, takes lines from frames above the current
5610 	 * frame.
5611 	 */
5612 	for (run = 0; run < 2; ++run)
5613 	{
5614 	    if (run == 0)
5615 		frp = curfrp->fr_next;	// 1st run: start with next window
5616 	    else
5617 		frp = curfrp->fr_prev;	// 2nd run: start with prev window
5618 	    while (frp != NULL && take != 0)
5619 	    {
5620 		h = frame_minheight(frp, NULL);
5621 		if (room_reserved > 0
5622 			&& frp->fr_win != NULL
5623 			&& frp->fr_win->w_p_wfh)
5624 		{
5625 		    if (room_reserved >= frp->fr_height)
5626 			room_reserved -= frp->fr_height;
5627 		    else
5628 		    {
5629 			if (frp->fr_height - room_reserved > take)
5630 			    room_reserved = frp->fr_height - take;
5631 			take -= frp->fr_height - room_reserved;
5632 			frame_new_height(frp, room_reserved, FALSE, FALSE);
5633 			room_reserved = 0;
5634 		    }
5635 		}
5636 		else
5637 		{
5638 		    if (frp->fr_height - take < h)
5639 		    {
5640 			take -= frp->fr_height - h;
5641 			frame_new_height(frp, h, FALSE, FALSE);
5642 		    }
5643 		    else
5644 		    {
5645 			frame_new_height(frp, frp->fr_height - take,
5646 								FALSE, FALSE);
5647 			take = 0;
5648 		    }
5649 		}
5650 		if (run == 0)
5651 		    frp = frp->fr_next;
5652 		else
5653 		    frp = frp->fr_prev;
5654 	    }
5655 	}
5656     }
5657 }
5658 
5659 /*
5660  * Set current window width and take care of repositioning other windows to
5661  * fit around it.
5662  */
5663     void
5664 win_setwidth(int width)
5665 {
5666     win_setwidth_win(width, curwin);
5667 }
5668 
5669     void
5670 win_setwidth_win(int width, win_T *wp)
5671 {
5672     // Always keep current window at least one column wide, even when
5673     // 'winminwidth' is zero.
5674     if (wp == curwin)
5675     {
5676 	if (width < p_wmw)
5677 	    width = p_wmw;
5678 	if (width == 0)
5679 	    width = 1;
5680     }
5681 
5682     frame_setwidth(wp->w_frame, width + wp->w_vsep_width);
5683 
5684     // recompute the window positions
5685     (void)win_comp_pos();
5686 
5687     redraw_all_later(NOT_VALID);
5688 }
5689 
5690 /*
5691  * Set the width of a frame to "width" and take care that all frames and
5692  * windows inside it are resized.  Also resize frames above and below if the
5693  * are in the same FR_ROW frame.
5694  *
5695  * Strategy is similar to frame_setheight().
5696  */
5697     static void
5698 frame_setwidth(frame_T *curfrp, int width)
5699 {
5700     int		room;		// total number of lines available
5701     int		take;		// number of lines taken from other windows
5702     int		run;
5703     frame_T	*frp;
5704     int		w;
5705     int		room_reserved;
5706 
5707     // If the width already is the desired value, nothing to do.
5708     if (curfrp->fr_width == width)
5709 	return;
5710 
5711     if (curfrp->fr_parent == NULL)
5712 	// topframe: can't change width
5713 	return;
5714 
5715     if (curfrp->fr_parent->fr_layout == FR_COL)
5716     {
5717 	// Column of frames: Also need to resize frames above and below of
5718 	// this one.  First check for the minimal width of these.
5719 	w = frame_minwidth(curfrp->fr_parent, NULL);
5720 	if (width < w)
5721 	    width = w;
5722 	frame_setwidth(curfrp->fr_parent, width);
5723     }
5724     else
5725     {
5726 	/*
5727 	 * Row of frames: try to change only frames in this row.
5728 	 *
5729 	 * Do this twice:
5730 	 * 1: compute room available, if it's not enough try resizing the
5731 	 *    containing frame.
5732 	 * 2: compute the room available and adjust the width to it.
5733 	 */
5734 	for (run = 1; run <= 2; ++run)
5735 	{
5736 	    room = 0;
5737 	    room_reserved = 0;
5738 	    FOR_ALL_FRAMES(frp, curfrp->fr_parent->fr_child)
5739 	    {
5740 		if (frp != curfrp
5741 			&& frp->fr_win != NULL
5742 			&& frp->fr_win->w_p_wfw)
5743 		    room_reserved += frp->fr_width;
5744 		room += frp->fr_width;
5745 		if (frp != curfrp)
5746 		    room -= frame_minwidth(frp, NULL);
5747 	    }
5748 
5749 	    if (width <= room)
5750 		break;
5751 	    if (run == 2 || curfrp->fr_height >= ROWS_AVAIL)
5752 	    {
5753 		if (width > room)
5754 		    width = room;
5755 		break;
5756 	    }
5757 	    frame_setwidth(curfrp->fr_parent, width
5758 		 + frame_minwidth(curfrp->fr_parent, NOWIN) - (int)p_wmw - 1);
5759 	}
5760 
5761 	/*
5762 	 * Compute the number of lines we will take from others frames (can be
5763 	 * negative!).
5764 	 */
5765 	take = width - curfrp->fr_width;
5766 
5767 	// If there is not enough room, also reduce the width of a window
5768 	// with 'winfixwidth' set.
5769 	if (width > room - room_reserved)
5770 	    room_reserved = room - width;
5771 	// If there is only a 'winfixwidth' window and making the
5772 	// window smaller, need to make the other window narrower.
5773 	if (take < 0 && room - curfrp->fr_width < room_reserved)
5774 	    room_reserved = 0;
5775 
5776 	/*
5777 	 * set the current frame to the new width
5778 	 */
5779 	frame_new_width(curfrp, width, FALSE, FALSE);
5780 
5781 	/*
5782 	 * First take lines from the frames right of the current frame.  If
5783 	 * that is not enough, takes lines from frames left of the current
5784 	 * frame.
5785 	 */
5786 	for (run = 0; run < 2; ++run)
5787 	{
5788 	    if (run == 0)
5789 		frp = curfrp->fr_next;	// 1st run: start with next window
5790 	    else
5791 		frp = curfrp->fr_prev;	// 2nd run: start with prev window
5792 	    while (frp != NULL && take != 0)
5793 	    {
5794 		w = frame_minwidth(frp, NULL);
5795 		if (room_reserved > 0
5796 			&& frp->fr_win != NULL
5797 			&& frp->fr_win->w_p_wfw)
5798 		{
5799 		    if (room_reserved >= frp->fr_width)
5800 			room_reserved -= frp->fr_width;
5801 		    else
5802 		    {
5803 			if (frp->fr_width - room_reserved > take)
5804 			    room_reserved = frp->fr_width - take;
5805 			take -= frp->fr_width - room_reserved;
5806 			frame_new_width(frp, room_reserved, FALSE, FALSE);
5807 			room_reserved = 0;
5808 		    }
5809 		}
5810 		else
5811 		{
5812 		    if (frp->fr_width - take < w)
5813 		    {
5814 			take -= frp->fr_width - w;
5815 			frame_new_width(frp, w, FALSE, FALSE);
5816 		    }
5817 		    else
5818 		    {
5819 			frame_new_width(frp, frp->fr_width - take,
5820 								FALSE, FALSE);
5821 			take = 0;
5822 		    }
5823 		}
5824 		if (run == 0)
5825 		    frp = frp->fr_next;
5826 		else
5827 		    frp = frp->fr_prev;
5828 	    }
5829 	}
5830     }
5831 }
5832 
5833 /*
5834  * Check 'winminheight' for a valid value and reduce it if needed.
5835  */
5836     void
5837 win_setminheight(void)
5838 {
5839     int		room;
5840     int		needed;
5841     int		first = TRUE;
5842 
5843     // loop until there is a 'winminheight' that is possible
5844     while (p_wmh > 0)
5845     {
5846 	room = Rows - p_ch;
5847 	needed = frame_minheight(topframe, NULL);
5848 	if (room >= needed)
5849 	    break;
5850 	--p_wmh;
5851 	if (first)
5852 	{
5853 	    emsg(_(e_noroom));
5854 	    first = FALSE;
5855 	}
5856     }
5857 }
5858 
5859 /*
5860  * Check 'winminwidth' for a valid value and reduce it if needed.
5861  */
5862     void
5863 win_setminwidth(void)
5864 {
5865     int		room;
5866     int		needed;
5867     int		first = TRUE;
5868 
5869     // loop until there is a 'winminheight' that is possible
5870     while (p_wmw > 0)
5871     {
5872 	room = Columns;
5873 	needed = frame_minwidth(topframe, NULL);
5874 	if (room >= needed)
5875 	    break;
5876 	--p_wmw;
5877 	if (first)
5878 	{
5879 	    emsg(_(e_noroom));
5880 	    first = FALSE;
5881 	}
5882     }
5883 }
5884 
5885 /*
5886  * Status line of dragwin is dragged "offset" lines down (negative is up).
5887  */
5888     void
5889 win_drag_status_line(win_T *dragwin, int offset)
5890 {
5891     frame_T	*curfr;
5892     frame_T	*fr;
5893     int		room;
5894     int		row;
5895     int		up;	// if TRUE, drag status line up, otherwise down
5896     int		n;
5897 
5898     fr = dragwin->w_frame;
5899     curfr = fr;
5900     if (fr != topframe)		// more than one window
5901     {
5902 	fr = fr->fr_parent;
5903 	// When the parent frame is not a column of frames, its parent should
5904 	// be.
5905 	if (fr->fr_layout != FR_COL)
5906 	{
5907 	    curfr = fr;
5908 	    if (fr != topframe)	// only a row of windows, may drag statusline
5909 		fr = fr->fr_parent;
5910 	}
5911     }
5912 
5913     // If this is the last frame in a column, may want to resize the parent
5914     // frame instead (go two up to skip a row of frames).
5915     while (curfr != topframe && curfr->fr_next == NULL)
5916     {
5917 	if (fr != topframe)
5918 	    fr = fr->fr_parent;
5919 	curfr = fr;
5920 	if (fr != topframe)
5921 	    fr = fr->fr_parent;
5922     }
5923 
5924     if (offset < 0) // drag up
5925     {
5926 	up = TRUE;
5927 	offset = -offset;
5928 	// sum up the room of the current frame and above it
5929 	if (fr == curfr)
5930 	{
5931 	    // only one window
5932 	    room = fr->fr_height - frame_minheight(fr, NULL);
5933 	}
5934 	else
5935 	{
5936 	    room = 0;
5937 	    for (fr = fr->fr_child; ; fr = fr->fr_next)
5938 	    {
5939 		room += fr->fr_height - frame_minheight(fr, NULL);
5940 		if (fr == curfr)
5941 		    break;
5942 	    }
5943 	}
5944 	fr = curfr->fr_next;		// put fr at frame that grows
5945     }
5946     else    // drag down
5947     {
5948 	up = FALSE;
5949 	/*
5950 	 * Only dragging the last status line can reduce p_ch.
5951 	 */
5952 	room = Rows - cmdline_row;
5953 	if (curfr->fr_next == NULL)
5954 	    room -= 1;
5955 	else
5956 	    room -= p_ch;
5957 	if (room < 0)
5958 	    room = 0;
5959 	// sum up the room of frames below of the current one
5960 	FOR_ALL_FRAMES(fr, curfr->fr_next)
5961 	    room += fr->fr_height - frame_minheight(fr, NULL);
5962 	fr = curfr;			// put fr at window that grows
5963     }
5964 
5965     if (room < offset)		// Not enough room
5966 	offset = room;		// Move as far as we can
5967     if (offset <= 0)
5968 	return;
5969 
5970     /*
5971      * Grow frame fr by "offset" lines.
5972      * Doesn't happen when dragging the last status line up.
5973      */
5974     if (fr != NULL)
5975 	frame_new_height(fr, fr->fr_height + offset, up, FALSE);
5976 
5977     if (up)
5978 	fr = curfr;		// current frame gets smaller
5979     else
5980 	fr = curfr->fr_next;	// next frame gets smaller
5981 
5982     /*
5983      * Now make the other frames smaller.
5984      */
5985     while (fr != NULL && offset > 0)
5986     {
5987 	n = frame_minheight(fr, NULL);
5988 	if (fr->fr_height - offset <= n)
5989 	{
5990 	    offset -= fr->fr_height - n;
5991 	    frame_new_height(fr, n, !up, FALSE);
5992 	}
5993 	else
5994 	{
5995 	    frame_new_height(fr, fr->fr_height - offset, !up, FALSE);
5996 	    break;
5997 	}
5998 	if (up)
5999 	    fr = fr->fr_prev;
6000 	else
6001 	    fr = fr->fr_next;
6002     }
6003     row = win_comp_pos();
6004     screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
6005     cmdline_row = row;
6006     p_ch = Rows - cmdline_row;
6007     if (p_ch < 1)
6008 	p_ch = 1;
6009     curtab->tp_ch_used = p_ch;
6010     redraw_all_later(SOME_VALID);
6011     showmode();
6012 }
6013 
6014 /*
6015  * Separator line of dragwin is dragged "offset" lines right (negative is left).
6016  */
6017     void
6018 win_drag_vsep_line(win_T *dragwin, int offset)
6019 {
6020     frame_T	*curfr;
6021     frame_T	*fr;
6022     int		room;
6023     int		left;	// if TRUE, drag separator line left, otherwise right
6024     int		n;
6025 
6026     fr = dragwin->w_frame;
6027     if (fr == topframe)		// only one window (cannot happen?)
6028 	return;
6029     curfr = fr;
6030     fr = fr->fr_parent;
6031     // When the parent frame is not a row of frames, its parent should be.
6032     if (fr->fr_layout != FR_ROW)
6033     {
6034 	if (fr == topframe)	// only a column of windows (cannot happen?)
6035 	    return;
6036 	curfr = fr;
6037 	fr = fr->fr_parent;
6038     }
6039 
6040     // If this is the last frame in a row, may want to resize a parent
6041     // frame instead.
6042     while (curfr->fr_next == NULL)
6043     {
6044 	if (fr == topframe)
6045 	    break;
6046 	curfr = fr;
6047 	fr = fr->fr_parent;
6048 	if (fr != topframe)
6049 	{
6050 	    curfr = fr;
6051 	    fr = fr->fr_parent;
6052 	}
6053     }
6054 
6055     if (offset < 0) // drag left
6056     {
6057 	left = TRUE;
6058 	offset = -offset;
6059 	// sum up the room of the current frame and left of it
6060 	room = 0;
6061 	for (fr = fr->fr_child; ; fr = fr->fr_next)
6062 	{
6063 	    room += fr->fr_width - frame_minwidth(fr, NULL);
6064 	    if (fr == curfr)
6065 		break;
6066 	}
6067 	fr = curfr->fr_next;		// put fr at frame that grows
6068     }
6069     else    // drag right
6070     {
6071 	left = FALSE;
6072 	// sum up the room of frames right of the current one
6073 	room = 0;
6074 	FOR_ALL_FRAMES(fr, curfr->fr_next)
6075 	    room += fr->fr_width - frame_minwidth(fr, NULL);
6076 	fr = curfr;			// put fr at window that grows
6077     }
6078 
6079     if (room < offset)		// Not enough room
6080 	offset = room;		// Move as far as we can
6081     if (offset <= 0)		// No room at all, quit.
6082 	return;
6083     if (fr == NULL)
6084 	return;			// Safety check, should not happen.
6085 
6086     // grow frame fr by offset lines
6087     frame_new_width(fr, fr->fr_width + offset, left, FALSE);
6088 
6089     // shrink other frames: current and at the left or at the right
6090     if (left)
6091 	fr = curfr;		// current frame gets smaller
6092     else
6093 	fr = curfr->fr_next;	// next frame gets smaller
6094 
6095     while (fr != NULL && offset > 0)
6096     {
6097 	n = frame_minwidth(fr, NULL);
6098 	if (fr->fr_width - offset <= n)
6099 	{
6100 	    offset -= fr->fr_width - n;
6101 	    frame_new_width(fr, n, !left, FALSE);
6102 	}
6103 	else
6104 	{
6105 	    frame_new_width(fr, fr->fr_width - offset, !left, FALSE);
6106 	    break;
6107 	}
6108 	if (left)
6109 	    fr = fr->fr_prev;
6110 	else
6111 	    fr = fr->fr_next;
6112     }
6113     (void)win_comp_pos();
6114     redraw_all_later(NOT_VALID);
6115 }
6116 
6117 #define FRACTION_MULT	16384L
6118 
6119 /*
6120  * Set wp->w_fraction for the current w_wrow and w_height.
6121  * Has no effect when the window is less than two lines.
6122  */
6123     void
6124 set_fraction(win_T *wp)
6125 {
6126     if (wp->w_height > 1)
6127 	// When cursor is in the first line the percentage is computed as if
6128 	// it's halfway that line.  Thus with two lines it is 25%, with three
6129 	// lines 17%, etc.  Similarly for the last line: 75%, 83%, etc.
6130 	wp->w_fraction = ((long)wp->w_wrow * FRACTION_MULT
6131 				     + FRACTION_MULT / 2) / (long)wp->w_height;
6132 }
6133 
6134 /*
6135  * Set the height of a window.
6136  * "height" excludes any window toolbar.
6137  * This takes care of the things inside the window, not what happens to the
6138  * window position, the frame or to other windows.
6139  */
6140     void
6141 win_new_height(win_T *wp, int height)
6142 {
6143     int		prev_height = wp->w_height;
6144 
6145     // Don't want a negative height.  Happens when splitting a tiny window.
6146     // Will equalize heights soon to fix it.
6147     if (height < 0)
6148 	height = 0;
6149     if (wp->w_height == height)
6150 	return;	    // nothing to do
6151 
6152     if (wp->w_height > 0)
6153     {
6154 	if (wp == curwin)
6155 	    // w_wrow needs to be valid. When setting 'laststatus' this may
6156 	    // call win_new_height() recursively.
6157 	    validate_cursor();
6158 	if (wp->w_height != prev_height)
6159 	    return;  // Recursive call already changed the size, bail out here
6160 		     //	to avoid the following to mess things up.
6161 	if (wp->w_wrow != wp->w_prev_fraction_row)
6162 	    set_fraction(wp);
6163     }
6164 
6165     wp->w_height = height;
6166     wp->w_skipcol = 0;
6167 
6168     // There is no point in adjusting the scroll position when exiting.  Some
6169     // values might be invalid.
6170     if (!exiting)
6171 	scroll_to_fraction(wp, prev_height);
6172 }
6173 
6174     void
6175 scroll_to_fraction(win_T *wp, int prev_height)
6176 {
6177     linenr_T	lnum;
6178     int		sline, line_size;
6179     int		height = wp->w_height;
6180 
6181     // Don't change w_topline in any of these cases:
6182     // - window height is 0
6183     // - 'scrollbind' is set and this isn't the current window
6184     // - window height is sufficient to display the whole buffer and first line
6185     //   is visible.
6186     if (height > 0
6187         && (!wp->w_p_scb || wp == curwin)
6188         && (height < wp->w_buffer->b_ml.ml_line_count || wp->w_topline > 1))
6189     {
6190 	/*
6191 	 * Find a value for w_topline that shows the cursor at the same
6192 	 * relative position in the window as before (more or less).
6193 	 */
6194 	lnum = wp->w_cursor.lnum;
6195 	if (lnum < 1)		// can happen when starting up
6196 	    lnum = 1;
6197 	wp->w_wrow = ((long)wp->w_fraction * (long)height - 1L)
6198 							       / FRACTION_MULT;
6199 	line_size = plines_win_col(wp, lnum, (long)(wp->w_cursor.col)) - 1;
6200 	sline = wp->w_wrow - line_size;
6201 
6202 	if (sline >= 0)
6203 	{
6204 	    // Make sure the whole cursor line is visible, if possible.
6205 	    int rows = plines_win(wp, lnum, FALSE);
6206 
6207 	    if (sline > wp->w_height - rows)
6208 	    {
6209 		sline = wp->w_height - rows;
6210 		wp->w_wrow -= rows - line_size;
6211 	    }
6212 	}
6213 
6214 	if (sline < 0)
6215 	{
6216 	    /*
6217 	     * Cursor line would go off top of screen if w_wrow was this high.
6218 	     * Make cursor line the first line in the window.  If not enough
6219 	     * room use w_skipcol;
6220 	     */
6221 	    wp->w_wrow = line_size;
6222 	    if (wp->w_wrow >= wp->w_height
6223 				       && (wp->w_width - win_col_off(wp)) > 0)
6224 	    {
6225 		wp->w_skipcol += wp->w_width - win_col_off(wp);
6226 		--wp->w_wrow;
6227 		while (wp->w_wrow >= wp->w_height)
6228 		{
6229 		    wp->w_skipcol += wp->w_width - win_col_off(wp)
6230 							   + win_col_off2(wp);
6231 		    --wp->w_wrow;
6232 		}
6233 	    }
6234 	}
6235 	else if (sline > 0)
6236 	{
6237 	    while (sline > 0 && lnum > 1)
6238 	    {
6239 #ifdef FEAT_FOLDING
6240 		hasFoldingWin(wp, lnum, &lnum, NULL, TRUE, NULL);
6241 		if (lnum == 1)
6242 		{
6243 		    // first line in buffer is folded
6244 		    line_size = 1;
6245 		    --sline;
6246 		    break;
6247 		}
6248 #endif
6249 		--lnum;
6250 #ifdef FEAT_DIFF
6251 		if (lnum == wp->w_topline)
6252 		    line_size = plines_win_nofill(wp, lnum, TRUE)
6253 							      + wp->w_topfill;
6254 		else
6255 #endif
6256 		    line_size = plines_win(wp, lnum, TRUE);
6257 		sline -= line_size;
6258 	    }
6259 
6260 	    if (sline < 0)
6261 	    {
6262 		/*
6263 		 * Line we want at top would go off top of screen.  Use next
6264 		 * line instead.
6265 		 */
6266 #ifdef FEAT_FOLDING
6267 		hasFoldingWin(wp, lnum, NULL, &lnum, TRUE, NULL);
6268 #endif
6269 		lnum++;
6270 		wp->w_wrow -= line_size + sline;
6271 	    }
6272 	    else if (sline > 0)
6273 	    {
6274 		// First line of file reached, use that as topline.
6275 		lnum = 1;
6276 		wp->w_wrow -= sline;
6277 	    }
6278 	}
6279 	set_topline(wp, lnum);
6280     }
6281 
6282     if (wp == curwin)
6283     {
6284 	if (get_scrolloff_value())
6285 	    update_topline();
6286 	curs_columns(FALSE);	// validate w_wrow
6287     }
6288     if (prev_height > 0)
6289 	wp->w_prev_fraction_row = wp->w_wrow;
6290 
6291     win_comp_scroll(wp);
6292     redraw_win_later(wp, SOME_VALID);
6293     wp->w_redr_status = TRUE;
6294     invalidate_botline_win(wp);
6295 }
6296 
6297 /*
6298  * Set the width of a window.
6299  */
6300     void
6301 win_new_width(win_T *wp, int width)
6302 {
6303     wp->w_width = width;
6304     wp->w_lines_valid = 0;
6305     changed_line_abv_curs_win(wp);
6306     invalidate_botline_win(wp);
6307     if (wp == curwin)
6308     {
6309 	update_topline();
6310 	curs_columns(TRUE);	// validate w_wrow
6311     }
6312     redraw_win_later(wp, NOT_VALID);
6313     wp->w_redr_status = TRUE;
6314 }
6315 
6316     void
6317 win_comp_scroll(win_T *wp)
6318 {
6319     wp->w_p_scr = ((unsigned)wp->w_height >> 1);
6320     if (wp->w_p_scr == 0)
6321 	wp->w_p_scr = 1;
6322 }
6323 
6324 /*
6325  * command_height: called whenever p_ch has been changed
6326  */
6327     void
6328 command_height(void)
6329 {
6330     int		h;
6331     frame_T	*frp;
6332     int		old_p_ch = curtab->tp_ch_used;
6333 
6334     // Use the value of p_ch that we remembered.  This is needed for when the
6335     // GUI starts up, we can't be sure in what order things happen.  And when
6336     // p_ch was changed in another tab page.
6337     curtab->tp_ch_used = p_ch;
6338 
6339     // Find bottom frame with width of screen.
6340     frp = lastwin->w_frame;
6341     while (frp->fr_width != Columns && frp->fr_parent != NULL)
6342 	frp = frp->fr_parent;
6343 
6344     // Avoid changing the height of a window with 'winfixheight' set.
6345     while (frp->fr_prev != NULL && frp->fr_layout == FR_LEAF
6346 						      && frp->fr_win->w_p_wfh)
6347 	frp = frp->fr_prev;
6348 
6349     if (starting != NO_SCREEN)
6350     {
6351 	cmdline_row = Rows - p_ch;
6352 
6353 	if (p_ch > old_p_ch)		    // p_ch got bigger
6354 	{
6355 	    while (p_ch > old_p_ch)
6356 	    {
6357 		if (frp == NULL)
6358 		{
6359 		    emsg(_(e_noroom));
6360 		    p_ch = old_p_ch;
6361 		    curtab->tp_ch_used = p_ch;
6362 		    cmdline_row = Rows - p_ch;
6363 		    break;
6364 		}
6365 		h = frp->fr_height - frame_minheight(frp, NULL);
6366 		if (h > p_ch - old_p_ch)
6367 		    h = p_ch - old_p_ch;
6368 		old_p_ch += h;
6369 		frame_add_height(frp, -h);
6370 		frp = frp->fr_prev;
6371 	    }
6372 
6373 	    // Recompute window positions.
6374 	    (void)win_comp_pos();
6375 
6376 	    // clear the lines added to cmdline
6377 	    if (full_screen)
6378 		screen_fill((int)(cmdline_row), (int)Rows, 0,
6379 						   (int)Columns, ' ', ' ', 0);
6380 	    msg_row = cmdline_row;
6381 	    redraw_cmdline = TRUE;
6382 	    return;
6383 	}
6384 
6385 	if (msg_row < cmdline_row)
6386 	    msg_row = cmdline_row;
6387 	redraw_cmdline = TRUE;
6388     }
6389     frame_add_height(frp, (int)(old_p_ch - p_ch));
6390 
6391     // Recompute window positions.
6392     if (frp != lastwin->w_frame)
6393 	(void)win_comp_pos();
6394 }
6395 
6396 /*
6397  * Resize frame "frp" to be "n" lines higher (negative for less high).
6398  * Also resize the frames it is contained in.
6399  */
6400     static void
6401 frame_add_height(frame_T *frp, int n)
6402 {
6403     frame_new_height(frp, frp->fr_height + n, FALSE, FALSE);
6404     for (;;)
6405     {
6406 	frp = frp->fr_parent;
6407 	if (frp == NULL)
6408 	    break;
6409 	frp->fr_height += n;
6410     }
6411 }
6412 
6413 /*
6414  * Add or remove a status line for the bottom window(s), according to the
6415  * value of 'laststatus'.
6416  */
6417     void
6418 last_status(
6419     int		morewin)	// pretend there are two or more windows
6420 {
6421     // Don't make a difference between horizontal or vertical split.
6422     last_status_rec(topframe, (p_ls == 2
6423 			  || (p_ls == 1 && (morewin || !ONE_WINDOW))));
6424 }
6425 
6426     static void
6427 last_status_rec(frame_T *fr, int statusline)
6428 {
6429     frame_T	*fp;
6430     win_T	*wp;
6431 
6432     if (fr->fr_layout == FR_LEAF)
6433     {
6434 	wp = fr->fr_win;
6435 	if (wp->w_status_height != 0 && !statusline)
6436 	{
6437 	    // remove status line
6438 	    win_new_height(wp, wp->w_height + 1);
6439 	    wp->w_status_height = 0;
6440 	    comp_col();
6441 	}
6442 	else if (wp->w_status_height == 0 && statusline)
6443 	{
6444 	    // Find a frame to take a line from.
6445 	    fp = fr;
6446 	    while (fp->fr_height <= frame_minheight(fp, NULL))
6447 	    {
6448 		if (fp == topframe)
6449 		{
6450 		    emsg(_(e_noroom));
6451 		    return;
6452 		}
6453 		// In a column of frames: go to frame above.  If already at
6454 		// the top or in a row of frames: go to parent.
6455 		if (fp->fr_parent->fr_layout == FR_COL && fp->fr_prev != NULL)
6456 		    fp = fp->fr_prev;
6457 		else
6458 		    fp = fp->fr_parent;
6459 	    }
6460 	    wp->w_status_height = 1;
6461 	    if (fp != fr)
6462 	    {
6463 		frame_new_height(fp, fp->fr_height - 1, FALSE, FALSE);
6464 		frame_fix_height(wp);
6465 		(void)win_comp_pos();
6466 	    }
6467 	    else
6468 		win_new_height(wp, wp->w_height - 1);
6469 	    comp_col();
6470 	    redraw_all_later(SOME_VALID);
6471 	}
6472     }
6473     else if (fr->fr_layout == FR_ROW)
6474     {
6475 	// vertically split windows, set status line for each one
6476 	FOR_ALL_FRAMES(fp, fr->fr_child)
6477 	    last_status_rec(fp, statusline);
6478     }
6479     else
6480     {
6481 	// horizontally split window, set status line for last one
6482 	for (fp = fr->fr_child; fp->fr_next != NULL; fp = fp->fr_next)
6483 	    ;
6484 	last_status_rec(fp, statusline);
6485     }
6486 }
6487 
6488 /*
6489  * Return the number of lines used by the tab page line.
6490  */
6491     int
6492 tabline_height(void)
6493 {
6494 #ifdef FEAT_GUI_TABLINE
6495     // When the GUI has the tabline then this always returns zero.
6496     if (gui_use_tabline())
6497 	return 0;
6498 #endif
6499     switch (p_stal)
6500     {
6501 	case 0: return 0;
6502 	case 1: return (first_tabpage->tp_next == NULL) ? 0 : 1;
6503     }
6504     return 1;
6505 }
6506 
6507 /*
6508  * Return the minimal number of rows that is needed on the screen to display
6509  * the current number of windows.
6510  */
6511     int
6512 min_rows(void)
6513 {
6514     int		total;
6515     tabpage_T	*tp;
6516     int		n;
6517 
6518     if (firstwin == NULL)	// not initialized yet
6519 	return MIN_LINES;
6520 
6521     total = 0;
6522     FOR_ALL_TABPAGES(tp)
6523     {
6524 	n = frame_minheight(tp->tp_topframe, NULL);
6525 	if (total < n)
6526 	    total = n;
6527     }
6528     total += tabline_height();
6529     total += 1;		// count the room for the command line
6530     return total;
6531 }
6532 
6533 /*
6534  * Return TRUE if there is only one window and only one tab page, not
6535  * counting a help or preview window, unless it is the current window.
6536  * Does not count unlisted windows.
6537  */
6538     int
6539 only_one_window(void)
6540 {
6541     int		count = 0;
6542     win_T	*wp;
6543 
6544 #if defined(FEAT_PROP_POPUP)
6545     // If the current window is a popup then there always is another window.
6546     if (popup_is_popup(curwin))
6547 	return FALSE;
6548 #endif
6549 
6550     // If there is another tab page there always is another window.
6551     if (first_tabpage->tp_next != NULL)
6552 	return FALSE;
6553 
6554     FOR_ALL_WINDOWS(wp)
6555 	if (wp->w_buffer != NULL
6556 		&& (!((bt_help(wp->w_buffer) && !bt_help(curbuf))
6557 # ifdef FEAT_QUICKFIX
6558 		    || wp->w_p_pvw
6559 # endif
6560 	     ) || wp == curwin) && wp != aucmd_win)
6561 	    ++count;
6562     return (count <= 1);
6563 }
6564 
6565 /*
6566  * Correct the cursor line number in other windows.  Used after changing the
6567  * current buffer, and before applying autocommands.
6568  * When "do_curwin" is TRUE, also check current window.
6569  */
6570     void
6571 check_lnums(int do_curwin)
6572 {
6573     win_T	*wp;
6574     tabpage_T	*tp;
6575 
6576     FOR_ALL_TAB_WINDOWS(tp, wp)
6577 	if ((do_curwin || wp != curwin) && wp->w_buffer == curbuf)
6578 	{
6579 	    // save the original cursor position and topline
6580 	    wp->w_save_cursor.w_cursor_save = wp->w_cursor;
6581 	    wp->w_save_cursor.w_topline_save = wp->w_topline;
6582 
6583 	    if (wp->w_cursor.lnum > curbuf->b_ml.ml_line_count)
6584 		wp->w_cursor.lnum = curbuf->b_ml.ml_line_count;
6585 	    if (wp->w_topline > curbuf->b_ml.ml_line_count)
6586 		wp->w_topline = curbuf->b_ml.ml_line_count;
6587 
6588 	    // save the corrected cursor position and topline
6589 	    wp->w_save_cursor.w_cursor_corr = wp->w_cursor;
6590 	    wp->w_save_cursor.w_topline_corr = wp->w_topline;
6591 	}
6592 }
6593 
6594 /*
6595  * Reset cursor and topline to its stored values from check_lnums().
6596  * check_lnums() must have been called first!
6597  */
6598     void
6599 reset_lnums()
6600 {
6601     win_T	*wp;
6602     tabpage_T	*tp;
6603 
6604     FOR_ALL_TAB_WINDOWS(tp, wp)
6605 	if (wp->w_buffer == curbuf)
6606 	{
6607 	    // Restore the value if the autocommand didn't change it.
6608 	    if (EQUAL_POS(wp->w_save_cursor.w_cursor_corr, wp->w_cursor))
6609 		wp->w_cursor = wp->w_save_cursor.w_cursor_save;
6610 	    if (wp->w_save_cursor.w_topline_corr == wp->w_topline)
6611 		wp->w_topline = wp->w_save_cursor.w_topline_save;
6612 	}
6613 }
6614 
6615 /*
6616  * A snapshot of the window sizes, to restore them after closing the help
6617  * window.
6618  * Only these fields are used:
6619  * fr_layout
6620  * fr_width
6621  * fr_height
6622  * fr_next
6623  * fr_child
6624  * fr_win (only valid for the old curwin, NULL otherwise)
6625  */
6626 
6627 /*
6628  * Create a snapshot of the current frame sizes.
6629  */
6630     void
6631 make_snapshot(int idx)
6632 {
6633     clear_snapshot(curtab, idx);
6634     make_snapshot_rec(topframe, &curtab->tp_snapshot[idx]);
6635 }
6636 
6637     static void
6638 make_snapshot_rec(frame_T *fr, frame_T **frp)
6639 {
6640     *frp = ALLOC_CLEAR_ONE(frame_T);
6641     if (*frp == NULL)
6642 	return;
6643     (*frp)->fr_layout = fr->fr_layout;
6644     (*frp)->fr_width = fr->fr_width;
6645     (*frp)->fr_height = fr->fr_height;
6646     if (fr->fr_next != NULL)
6647 	make_snapshot_rec(fr->fr_next, &((*frp)->fr_next));
6648     if (fr->fr_child != NULL)
6649 	make_snapshot_rec(fr->fr_child, &((*frp)->fr_child));
6650     if (fr->fr_layout == FR_LEAF && fr->fr_win == curwin)
6651 	(*frp)->fr_win = curwin;
6652 }
6653 
6654 /*
6655  * Remove any existing snapshot.
6656  */
6657     static void
6658 clear_snapshot(tabpage_T *tp, int idx)
6659 {
6660     clear_snapshot_rec(tp->tp_snapshot[idx]);
6661     tp->tp_snapshot[idx] = NULL;
6662 }
6663 
6664     static void
6665 clear_snapshot_rec(frame_T *fr)
6666 {
6667     if (fr != NULL)
6668     {
6669 	clear_snapshot_rec(fr->fr_next);
6670 	clear_snapshot_rec(fr->fr_child);
6671 	vim_free(fr);
6672     }
6673 }
6674 
6675 /*
6676  * Restore a previously created snapshot, if there is any.
6677  * This is only done if the screen size didn't change and the window layout is
6678  * still the same.
6679  */
6680     void
6681 restore_snapshot(
6682     int		idx,
6683     int		close_curwin)	    // closing current window
6684 {
6685     win_T	*wp;
6686 
6687     if (curtab->tp_snapshot[idx] != NULL
6688 	    && curtab->tp_snapshot[idx]->fr_width == topframe->fr_width
6689 	    && curtab->tp_snapshot[idx]->fr_height == topframe->fr_height
6690 	    && check_snapshot_rec(curtab->tp_snapshot[idx], topframe) == OK)
6691     {
6692 	wp = restore_snapshot_rec(curtab->tp_snapshot[idx], topframe);
6693 	win_comp_pos();
6694 	if (wp != NULL && close_curwin)
6695 	    win_goto(wp);
6696 	redraw_all_later(NOT_VALID);
6697     }
6698     clear_snapshot(curtab, idx);
6699 }
6700 
6701 /*
6702  * Check if frames "sn" and "fr" have the same layout, same following frames
6703  * and same children.  And the window pointer is valid.
6704  */
6705     static int
6706 check_snapshot_rec(frame_T *sn, frame_T *fr)
6707 {
6708     if (sn->fr_layout != fr->fr_layout
6709 	    || (sn->fr_next == NULL) != (fr->fr_next == NULL)
6710 	    || (sn->fr_child == NULL) != (fr->fr_child == NULL)
6711 	    || (sn->fr_next != NULL
6712 		&& check_snapshot_rec(sn->fr_next, fr->fr_next) == FAIL)
6713 	    || (sn->fr_child != NULL
6714 		&& check_snapshot_rec(sn->fr_child, fr->fr_child) == FAIL)
6715 	    || (sn->fr_win != NULL && !win_valid(sn->fr_win)))
6716 	return FAIL;
6717     return OK;
6718 }
6719 
6720 /*
6721  * Copy the size of snapshot frame "sn" to frame "fr".  Do the same for all
6722  * following frames and children.
6723  * Returns a pointer to the old current window, or NULL.
6724  */
6725     static win_T *
6726 restore_snapshot_rec(frame_T *sn, frame_T *fr)
6727 {
6728     win_T	*wp = NULL;
6729     win_T	*wp2;
6730 
6731     fr->fr_height = sn->fr_height;
6732     fr->fr_width = sn->fr_width;
6733     if (fr->fr_layout == FR_LEAF)
6734     {
6735 	frame_new_height(fr, fr->fr_height, FALSE, FALSE);
6736 	frame_new_width(fr, fr->fr_width, FALSE, FALSE);
6737 	wp = sn->fr_win;
6738     }
6739     if (sn->fr_next != NULL)
6740     {
6741 	wp2 = restore_snapshot_rec(sn->fr_next, fr->fr_next);
6742 	if (wp2 != NULL)
6743 	    wp = wp2;
6744     }
6745     if (sn->fr_child != NULL)
6746     {
6747 	wp2 = restore_snapshot_rec(sn->fr_child, fr->fr_child);
6748 	if (wp2 != NULL)
6749 	    wp = wp2;
6750     }
6751     return wp;
6752 }
6753 
6754 #if defined(FEAT_GUI) || defined(PROTO)
6755 /*
6756  * Return TRUE if there is any vertically split window.
6757  */
6758     int
6759 win_hasvertsplit(void)
6760 {
6761     frame_T	*fr;
6762 
6763     if (topframe->fr_layout == FR_ROW)
6764 	return TRUE;
6765 
6766     if (topframe->fr_layout == FR_COL)
6767 	FOR_ALL_FRAMES(fr, topframe->fr_child)
6768 	    if (fr->fr_layout == FR_ROW)
6769 		return TRUE;
6770 
6771     return FALSE;
6772 }
6773 #endif
6774 
6775 #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) || defined(PROTO)
6776     int
6777 get_win_number(win_T *wp, win_T *first_win)
6778 {
6779     int		i = 1;
6780     win_T	*w;
6781 
6782     for (w = first_win; w != NULL && w != wp; w = W_NEXT(w))
6783 	++i;
6784 
6785     if (w == NULL)
6786 	return 0;
6787     else
6788 	return i;
6789 }
6790 
6791     int
6792 get_tab_number(tabpage_T *tp UNUSED)
6793 {
6794     int		i = 1;
6795     tabpage_T	*t;
6796 
6797     for (t = first_tabpage; t != NULL && t != tp; t = t->tp_next)
6798 	++i;
6799 
6800     if (t == NULL)
6801 	return 0;
6802     else
6803 	return i;
6804 }
6805 #endif
6806 
6807 /*
6808  * Return TRUE if "topfrp" and its children are at the right height.
6809  */
6810     static int
6811 frame_check_height(frame_T *topfrp, int height)
6812 {
6813     frame_T *frp;
6814 
6815     if (topfrp->fr_height != height)
6816 	return FALSE;
6817 
6818     if (topfrp->fr_layout == FR_ROW)
6819 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
6820 	    if (frp->fr_height != height)
6821 		return FALSE;
6822 
6823     return TRUE;
6824 }
6825 
6826 /*
6827  * Return TRUE if "topfrp" and its children are at the right width.
6828  */
6829     static int
6830 frame_check_width(frame_T *topfrp, int width)
6831 {
6832     frame_T *frp;
6833 
6834     if (topfrp->fr_width != width)
6835 	return FALSE;
6836 
6837     if (topfrp->fr_layout == FR_COL)
6838 	FOR_ALL_FRAMES(frp, topfrp->fr_child)
6839 	    if (frp->fr_width != width)
6840 		return FALSE;
6841 
6842     return TRUE;
6843 }
6844 
6845 #if defined(FEAT_SYN_HL) || defined(PROTO)
6846 /*
6847  * Simple int comparison function for use with qsort()
6848  */
6849     static int
6850 int_cmp(const void *a, const void *b)
6851 {
6852     return *(const int *)a - *(const int *)b;
6853 }
6854 
6855 /*
6856  * Handle setting 'colorcolumn' or 'textwidth' in window "wp".
6857  * Returns error message, NULL if it's OK.
6858  */
6859     char *
6860 check_colorcolumn(win_T *wp)
6861 {
6862     char_u	*s;
6863     int		col;
6864     int		count = 0;
6865     int		color_cols[256];
6866     int		i;
6867     int		j = 0;
6868 
6869     if (wp->w_buffer == NULL)
6870 	return NULL;  // buffer was closed
6871 
6872     for (s = wp->w_p_cc; *s != NUL && count < 255;)
6873     {
6874 	if (*s == '-' || *s == '+')
6875 	{
6876 	    // -N and +N: add to 'textwidth'
6877 	    col = (*s == '-') ? -1 : 1;
6878 	    ++s;
6879 	    if (!VIM_ISDIGIT(*s))
6880 		return e_invarg;
6881 	    col = col * getdigits(&s);
6882 	    if (wp->w_buffer->b_p_tw == 0)
6883 		goto skip;  // 'textwidth' not set, skip this item
6884 	    col += wp->w_buffer->b_p_tw;
6885 	    if (col < 0)
6886 		goto skip;
6887 	}
6888 	else if (VIM_ISDIGIT(*s))
6889 	    col = getdigits(&s);
6890 	else
6891 	    return e_invarg;
6892 	color_cols[count++] = col - 1;  // 1-based to 0-based
6893 skip:
6894 	if (*s == NUL)
6895 	    break;
6896 	if (*s != ',')
6897 	    return e_invarg;
6898 	if (*++s == NUL)
6899 	    return e_invarg;  // illegal trailing comma as in "set cc=80,"
6900     }
6901 
6902     vim_free(wp->w_p_cc_cols);
6903     if (count == 0)
6904 	wp->w_p_cc_cols = NULL;
6905     else
6906     {
6907 	wp->w_p_cc_cols = ALLOC_MULT(int, count + 1);
6908 	if (wp->w_p_cc_cols != NULL)
6909 	{
6910 	    // sort the columns for faster usage on screen redraw inside
6911 	    // win_line()
6912 	    qsort(color_cols, count, sizeof(int), int_cmp);
6913 
6914 	    for (i = 0; i < count; ++i)
6915 		// skip duplicates
6916 		if (j == 0 || wp->w_p_cc_cols[j - 1] != color_cols[i])
6917 		    wp->w_p_cc_cols[j++] = color_cols[i];
6918 	    wp->w_p_cc_cols[j] = -1;  // end marker
6919 	}
6920     }
6921 
6922     return NULL;  // no error
6923 }
6924 #endif
6925