xref: /vim-8.2.3635/src/window.c (revision f0d58efc)
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 int path_is_url(char_u *p);
13 static void cmd_with_count(char *cmd, char_u *bufp, size_t bufsize, long Prenum);
14 static void win_init(win_T *newp, win_T *oldp, int flags);
15 static void win_init_some(win_T *newp, win_T *oldp);
16 static void frame_comp_pos(frame_T *topfrp, int *row, int *col);
17 static void frame_setheight(frame_T *curfrp, int height);
18 static void frame_setwidth(frame_T *curfrp, int width);
19 static void win_exchange(long);
20 static void win_rotate(int, int);
21 static void win_totop(int size, int flags);
22 static void win_equal_rec(win_T *next_curwin, int current, frame_T *topfr, int dir, int col, int row, int width, int height);
23 static win_T *win_free_mem(win_T *win, int *dirp, tabpage_T *tp);
24 static frame_T *win_altframe(win_T *win, tabpage_T *tp);
25 static tabpage_T *alt_tabpage(void);
26 static win_T *frame2win(frame_T *frp);
27 static int frame_has_win(frame_T *frp, win_T *wp);
28 static void frame_new_height(frame_T *topfrp, int height, int topfirst, int wfh);
29 static int frame_fixed_height(frame_T *frp);
30 static int frame_fixed_width(frame_T *frp);
31 static void frame_add_statusline(frame_T *frp);
32 static void frame_new_width(frame_T *topfrp, int width, int leftfirst, int wfw);
33 static void frame_add_vsep(frame_T *frp);
34 static int frame_minwidth(frame_T *topfrp, win_T *next_curwin);
35 static void frame_fix_width(win_T *wp);
36 static int win_alloc_firstwin(win_T *oldwin);
37 static void new_frame(win_T *wp);
38 static tabpage_T *alloc_tabpage(void);
39 static int leave_tabpage(buf_T *new_curbuf, int trigger_leave_autocmds);
40 static void enter_tabpage(tabpage_T *tp, buf_T *old_curbuf, int trigger_enter_autocmds, int trigger_leave_autocmds);
41 static void frame_fix_height(win_T *wp);
42 static int frame_minheight(frame_T *topfrp, win_T *next_curwin);
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 void frame_append(frame_T *after, frame_T *frp);
46 static void frame_insert(frame_T *before, frame_T *frp);
47 static void frame_remove(frame_T *frp);
48 static void win_goto_ver(int up, long count);
49 static void win_goto_hor(int left, long count);
50 static void frame_add_height(frame_T *frp, int n);
51 static void last_status_rec(frame_T *fr, int statusline);
52 
53 static void make_snapshot_rec(frame_T *fr, frame_T **frp);
54 static void clear_snapshot(tabpage_T *tp, int idx);
55 static void clear_snapshot_rec(frame_T *fr);
56 static int check_snapshot_rec(frame_T *sn, frame_T *fr);
57 static win_T *restore_snapshot_rec(frame_T *sn, frame_T *fr);
58 
59 static int frame_check_height(frame_T *topfrp, int height);
60 static int frame_check_width(frame_T *topfrp, int width);
61 
62 static win_T *win_alloc(win_T *after, int hidden);
63 
64 #define URL_SLASH	1		/* path_is_url() has found "://" */
65 #define URL_BACKSLASH	2		/* path_is_url() has found ":\\" */
66 
67 #define NOWIN		(win_T *)-1	/* non-existing window */
68 
69 #define ROWS_AVAIL (Rows - p_ch - tabline_height())
70 
71 static char *m_onlyone = N_("Already only one window");
72 
73 /*
74  * all CTRL-W window commands are handled here, called from normal_cmd().
75  */
76     void
77 do_window(
78     int		nchar,
79     long	Prenum,
80     int		xchar)	    /* extra char from ":wincmd gx" or NUL */
81 {
82     long	Prenum1;
83     win_T	*wp;
84 #if defined(FEAT_SEARCHPATH) || defined(FEAT_FIND_ID)
85     char_u	*ptr;
86     linenr_T    lnum = -1;
87 #endif
88 #ifdef FEAT_FIND_ID
89     int		type = FIND_DEFINE;
90     int		len;
91 #endif
92     char_u	cbuf[40];
93 
94     if (Prenum == 0)
95 	Prenum1 = 1;
96     else
97 	Prenum1 = Prenum;
98 
99 #ifdef FEAT_CMDWIN
100 # define CHECK_CMDWIN \
101     do { \
102 	if (cmdwin_type != 0) \
103 	{ \
104 	    EMSG(_(e_cmdwin)); \
105 	    return; \
106 	} \
107     } while (0)
108 #else
109 # define CHECK_CMDWIN do { /**/ } while (0)
110 #endif
111 
112     switch (nchar)
113     {
114 /* split current window in two parts, horizontally */
115     case 'S':
116     case Ctrl_S:
117     case 's':
118 		CHECK_CMDWIN;
119 		reset_VIsual_and_resel();	/* stop Visual mode */
120 #ifdef FEAT_QUICKFIX
121 		/* When splitting the quickfix window open a new buffer in it,
122 		 * don't replicate the quickfix buffer. */
123 		if (bt_quickfix(curbuf))
124 		    goto newwindow;
125 #endif
126 #ifdef FEAT_GUI
127 		need_mouse_correct = TRUE;
128 #endif
129 		(void)win_split((int)Prenum, 0);
130 		break;
131 
132 /* split current window in two parts, vertically */
133     case Ctrl_V:
134     case 'v':
135 		CHECK_CMDWIN;
136 		reset_VIsual_and_resel();	/* stop Visual mode */
137 #ifdef FEAT_QUICKFIX
138 		/* When splitting the quickfix window open a new buffer in it,
139 		 * don't replicate the quickfix buffer. */
140 		if (bt_quickfix(curbuf))
141 		    goto newwindow;
142 #endif
143 #ifdef FEAT_GUI
144 		need_mouse_correct = TRUE;
145 #endif
146 		(void)win_split((int)Prenum, WSP_VERT);
147 		break;
148 
149 /* split current window and edit alternate file */
150     case Ctrl_HAT:
151     case '^':
152 		CHECK_CMDWIN;
153 		reset_VIsual_and_resel();	/* stop Visual mode */
154 
155 		if (buflist_findnr(Prenum == 0
156 					? curwin->w_alt_fnum : Prenum) == NULL)
157 		{
158 		    if (Prenum == 0)
159 			EMSG(_(e_noalt));
160 		    else
161 			EMSGN(_("E92: Buffer %ld not found"), Prenum);
162 		    break;
163 		}
164 
165 		if (!curbuf_locked() && win_split(0, 0) == OK)
166 		    (void)buflist_getfile(
167 			    Prenum == 0 ? curwin->w_alt_fnum : Prenum,
168 			    (linenr_T)0, GETF_ALT, FALSE);
169 		break;
170 
171 /* open new window */
172     case Ctrl_N:
173     case 'n':
174 		CHECK_CMDWIN;
175 		reset_VIsual_and_resel();	/* stop Visual mode */
176 #ifdef FEAT_QUICKFIX
177 newwindow:
178 #endif
179 		if (Prenum)
180 		    /* window height */
181 		    vim_snprintf((char *)cbuf, sizeof(cbuf) - 5, "%ld", Prenum);
182 		else
183 		    cbuf[0] = NUL;
184 #if defined(FEAT_QUICKFIX)
185 		if (nchar == 'v' || nchar == Ctrl_V)
186 		    STRCAT(cbuf, "v");
187 #endif
188 		STRCAT(cbuf, "new");
189 		do_cmdline_cmd(cbuf);
190 		break;
191 
192 /* quit current window */
193     case Ctrl_Q:
194     case 'q':
195 		reset_VIsual_and_resel();	/* stop Visual mode */
196 		cmd_with_count("quit", cbuf, sizeof(cbuf), Prenum);
197 		do_cmdline_cmd(cbuf);
198 		break;
199 
200 /* close current window */
201     case Ctrl_C:
202     case 'c':
203 		reset_VIsual_and_resel();	/* stop Visual mode */
204 		cmd_with_count("close", cbuf, sizeof(cbuf), Prenum);
205 		do_cmdline_cmd(cbuf);
206 		break;
207 
208 #if defined(FEAT_QUICKFIX)
209 /* close preview window */
210     case Ctrl_Z:
211     case 'z':
212 		CHECK_CMDWIN;
213 		reset_VIsual_and_resel();	/* stop Visual mode */
214 		do_cmdline_cmd((char_u *)"pclose");
215 		break;
216 
217 /* cursor to preview window */
218     case 'P':
219 		FOR_ALL_WINDOWS(wp)
220 		    if (wp->w_p_pvw)
221 			break;
222 		if (wp == NULL)
223 		    EMSG(_("E441: There is no preview window"));
224 		else
225 		    win_goto(wp);
226 		break;
227 #endif
228 
229 /* close all but current window */
230     case Ctrl_O:
231     case 'o':
232 		CHECK_CMDWIN;
233 		reset_VIsual_and_resel();	/* stop Visual mode */
234 		cmd_with_count("only", cbuf, sizeof(cbuf), Prenum);
235 		do_cmdline_cmd(cbuf);
236 		break;
237 
238 /* cursor to next window with wrap around */
239     case Ctrl_W:
240     case 'w':
241 /* cursor to previous window with wrap around */
242     case 'W':
243 		CHECK_CMDWIN;
244 		if (ONE_WINDOW && Prenum != 1)	/* just one window */
245 		    beep_flush();
246 		else
247 		{
248 		    if (Prenum)			/* go to specified window */
249 		    {
250 			for (wp = firstwin; --Prenum > 0; )
251 			{
252 			    if (wp->w_next == NULL)
253 				break;
254 			    else
255 				wp = wp->w_next;
256 			}
257 		    }
258 		    else
259 		    {
260 			if (nchar == 'W')	    /* go to previous window */
261 			{
262 			    wp = curwin->w_prev;
263 			    if (wp == NULL)
264 				wp = lastwin;	    /* wrap around */
265 			}
266 			else			    /* go to next window */
267 			{
268 			    wp = curwin->w_next;
269 			    if (wp == NULL)
270 				wp = firstwin;	    /* wrap around */
271 			}
272 		    }
273 		    win_goto(wp);
274 		}
275 		break;
276 
277 /* cursor to window below */
278     case 'j':
279     case K_DOWN:
280     case Ctrl_J:
281 		CHECK_CMDWIN;
282 		win_goto_ver(FALSE, Prenum1);
283 		break;
284 
285 /* cursor to window above */
286     case 'k':
287     case K_UP:
288     case Ctrl_K:
289 		CHECK_CMDWIN;
290 		win_goto_ver(TRUE, Prenum1);
291 		break;
292 
293 /* cursor to left window */
294     case 'h':
295     case K_LEFT:
296     case Ctrl_H:
297     case K_BS:
298 		CHECK_CMDWIN;
299 		win_goto_hor(TRUE, Prenum1);
300 		break;
301 
302 /* cursor to right window */
303     case 'l':
304     case K_RIGHT:
305     case Ctrl_L:
306 		CHECK_CMDWIN;
307 		win_goto_hor(FALSE, Prenum1);
308 		break;
309 
310 /* move window to new tab page */
311     case 'T':
312 		if (one_window())
313 		    MSG(_(m_onlyone));
314 		else
315 		{
316 		    tabpage_T	*oldtab = curtab;
317 		    tabpage_T	*newtab;
318 
319 		    /* First create a new tab with the window, then go back to
320 		     * the old tab and close the window there. */
321 		    wp = curwin;
322 		    if (win_new_tabpage((int)Prenum) == OK
323 						     && valid_tabpage(oldtab))
324 		    {
325 			newtab = curtab;
326 			goto_tabpage_tp(oldtab, TRUE, TRUE);
327 			if (curwin == wp)
328 			    win_close(curwin, FALSE);
329 			if (valid_tabpage(newtab))
330 			    goto_tabpage_tp(newtab, TRUE, TRUE);
331 		    }
332 		}
333 		break;
334 
335 /* cursor to top-left window */
336     case 't':
337     case Ctrl_T:
338 		win_goto(firstwin);
339 		break;
340 
341 /* cursor to bottom-right window */
342     case 'b':
343     case Ctrl_B:
344 		win_goto(lastwin);
345 		break;
346 
347 /* cursor to last accessed (previous) window */
348     case 'p':
349     case Ctrl_P:
350 		if (!win_valid(prevwin))
351 		    beep_flush();
352 		else
353 		    win_goto(prevwin);
354 		break;
355 
356 /* exchange current and next window */
357     case 'x':
358     case Ctrl_X:
359 		CHECK_CMDWIN;
360 		win_exchange(Prenum);
361 		break;
362 
363 /* rotate windows downwards */
364     case Ctrl_R:
365     case 'r':
366 		CHECK_CMDWIN;
367 		reset_VIsual_and_resel();	/* stop Visual mode */
368 		win_rotate(FALSE, (int)Prenum1);    /* downwards */
369 		break;
370 
371 /* rotate windows upwards */
372     case 'R':
373 		CHECK_CMDWIN;
374 		reset_VIsual_and_resel();	/* stop Visual mode */
375 		win_rotate(TRUE, (int)Prenum1);	    /* upwards */
376 		break;
377 
378 /* move window to the very top/bottom/left/right */
379     case 'K':
380     case 'J':
381     case 'H':
382     case 'L':
383 		CHECK_CMDWIN;
384 		win_totop((int)Prenum,
385 			((nchar == 'H' || nchar == 'L') ? WSP_VERT : 0)
386 			| ((nchar == 'H' || nchar == 'K') ? WSP_TOP : WSP_BOT));
387 		break;
388 
389 /* make all windows the same height */
390     case '=':
391 #ifdef FEAT_GUI
392 		need_mouse_correct = TRUE;
393 #endif
394 		win_equal(NULL, FALSE, 'b');
395 		break;
396 
397 /* increase current window height */
398     case '+':
399 #ifdef FEAT_GUI
400 		need_mouse_correct = TRUE;
401 #endif
402 		win_setheight(curwin->w_height + (int)Prenum1);
403 		break;
404 
405 /* decrease current window height */
406     case '-':
407 #ifdef FEAT_GUI
408 		need_mouse_correct = TRUE;
409 #endif
410 		win_setheight(curwin->w_height - (int)Prenum1);
411 		break;
412 
413 /* set current window height */
414     case Ctrl__:
415     case '_':
416 #ifdef FEAT_GUI
417 		need_mouse_correct = TRUE;
418 #endif
419 		win_setheight(Prenum ? (int)Prenum : 9999);
420 		break;
421 
422 /* increase current window width */
423     case '>':
424 #ifdef FEAT_GUI
425 		need_mouse_correct = TRUE;
426 #endif
427 		win_setwidth(curwin->w_width + (int)Prenum1);
428 		break;
429 
430 /* decrease current window width */
431     case '<':
432 #ifdef FEAT_GUI
433 		need_mouse_correct = TRUE;
434 #endif
435 		win_setwidth(curwin->w_width - (int)Prenum1);
436 		break;
437 
438 /* set current window width */
439     case '|':
440 #ifdef FEAT_GUI
441 		need_mouse_correct = TRUE;
442 #endif
443 		win_setwidth(Prenum != 0 ? (int)Prenum : 9999);
444 		break;
445 
446 /* jump to tag and split window if tag exists (in preview window) */
447 #if defined(FEAT_QUICKFIX)
448     case '}':
449 		CHECK_CMDWIN;
450 		if (Prenum)
451 		    g_do_tagpreview = Prenum;
452 		else
453 		    g_do_tagpreview = p_pvh;
454 #endif
455 		/* FALLTHROUGH */
456     case ']':
457     case Ctrl_RSB:
458 		CHECK_CMDWIN;
459 		/* keep Visual mode, can select words to use as a tag */
460 		if (Prenum)
461 		    postponed_split = Prenum;
462 		else
463 		    postponed_split = -1;
464 #ifdef FEAT_QUICKFIX
465 		if (nchar != '}')
466 		    g_do_tagpreview = 0;
467 #endif
468 
469 		/* Execute the command right here, required when "wincmd ]"
470 		 * was used in a function. */
471 		do_nv_ident(Ctrl_RSB, NUL);
472 		break;
473 
474 #ifdef FEAT_SEARCHPATH
475 /* edit file name under cursor in a new window */
476     case 'f':
477     case 'F':
478     case Ctrl_F:
479 wingotofile:
480 		CHECK_CMDWIN;
481 
482 		ptr = grab_file_name(Prenum1, &lnum);
483 		if (ptr != NULL)
484 		{
485 		    tabpage_T	*oldtab = curtab;
486 		    win_T	*oldwin = curwin;
487 # ifdef FEAT_GUI
488 		    need_mouse_correct = TRUE;
489 # endif
490 		    setpcmark();
491 		    if (win_split(0, 0) == OK)
492 		    {
493 			RESET_BINDING(curwin);
494 			if (do_ecmd(0, ptr, NULL, NULL, ECMD_LASTL,
495 						   ECMD_HIDE, NULL) == FAIL)
496 			{
497 			    /* Failed to open the file, close the window
498 			     * opened for it. */
499 			    win_close(curwin, FALSE);
500 			    goto_tabpage_win(oldtab, oldwin);
501 			}
502 			else if (nchar == 'F' && lnum >= 0)
503 			{
504 			    curwin->w_cursor.lnum = lnum;
505 			    check_cursor_lnum();
506 			    beginline(BL_SOL | BL_FIX);
507 			}
508 		    }
509 		    vim_free(ptr);
510 		}
511 		break;
512 #endif
513 
514 #ifdef FEAT_FIND_ID
515 /* Go to the first occurrence of the identifier under cursor along path in a
516  * new window -- webb
517  */
518     case 'i':			    /* Go to any match */
519     case Ctrl_I:
520 		type = FIND_ANY;
521 		/* FALLTHROUGH */
522     case 'd':			    /* Go to definition, using 'define' */
523     case Ctrl_D:
524 		CHECK_CMDWIN;
525 		if ((len = find_ident_under_cursor(&ptr, FIND_IDENT)) == 0)
526 		    break;
527 		find_pattern_in_path(ptr, 0, len, TRUE,
528 			Prenum == 0 ? TRUE : FALSE, type,
529 			Prenum1, ACTION_SPLIT, (linenr_T)1, (linenr_T)MAXLNUM);
530 		curwin->w_set_curswant = TRUE;
531 		break;
532 #endif
533 
534 /* Quickfix window only: view the result under the cursor in a new split. */
535 #if defined(FEAT_QUICKFIX)
536     case K_KENTER:
537     case CAR:
538 		if (bt_quickfix(curbuf))
539 		    qf_view_result(TRUE);
540 		break;
541 #endif
542 
543 /* CTRL-W g  extended commands */
544     case 'g':
545     case Ctrl_G:
546 		CHECK_CMDWIN;
547 #ifdef USE_ON_FLY_SCROLL
548 		dont_scroll = TRUE;		/* disallow scrolling here */
549 #endif
550 		++no_mapping;
551 		++allow_keys;   /* no mapping for xchar, but allow key codes */
552 		if (xchar == NUL)
553 		    xchar = plain_vgetc();
554 		LANGMAP_ADJUST(xchar, TRUE);
555 		--no_mapping;
556 		--allow_keys;
557 #ifdef FEAT_CMDL_INFO
558 		(void)add_to_showcmd(xchar);
559 #endif
560 		switch (xchar)
561 		{
562 #if defined(FEAT_QUICKFIX)
563 		    case '}':
564 			xchar = Ctrl_RSB;
565 			if (Prenum)
566 			    g_do_tagpreview = Prenum;
567 			else
568 			    g_do_tagpreview = p_pvh;
569 #endif
570 			/* FALLTHROUGH */
571 		    case ']':
572 		    case Ctrl_RSB:
573 			/* keep Visual mode, can select words to use as a tag */
574 			if (Prenum)
575 			    postponed_split = Prenum;
576 			else
577 			    postponed_split = -1;
578 
579 			/* Execute the command right here, required when
580 			 * "wincmd g}" was used in a function. */
581 			do_nv_ident('g', xchar);
582 			break;
583 
584 #ifdef FEAT_SEARCHPATH
585 		    case 'f':	    /* CTRL-W gf: "gf" in a new tab page */
586 		    case 'F':	    /* CTRL-W gF: "gF" in a new tab page */
587 			cmdmod.tab = tabpage_index(curtab) + 1;
588 			nchar = xchar;
589 			goto wingotofile;
590 #endif
591 		    default:
592 			beep_flush();
593 			break;
594 		}
595 		break;
596 
597     default:	beep_flush();
598 		break;
599     }
600 }
601 
602 /*
603  * Figure out the address type for ":wnncmd".
604  */
605     void
606 get_wincmd_addr_type(char_u *arg, exarg_T *eap)
607 {
608     switch (*arg)
609     {
610     case 'S':
611     case Ctrl_S:
612     case 's':
613     case Ctrl_N:
614     case 'n':
615     case 'j':
616     case Ctrl_J:
617     case 'k':
618     case Ctrl_K:
619     case 'T':
620     case Ctrl_R:
621     case 'r':
622     case 'R':
623     case 'K':
624     case 'J':
625     case '+':
626     case '-':
627     case Ctrl__:
628     case '_':
629     case '|':
630     case ']':
631     case Ctrl_RSB:
632     case 'g':
633     case Ctrl_G:
634     case Ctrl_V:
635     case 'v':
636     case 'h':
637     case Ctrl_H:
638     case 'l':
639     case Ctrl_L:
640     case 'H':
641     case 'L':
642     case '>':
643     case '<':
644 #if defined(FEAT_QUICKFIX)
645     case '}':
646 #endif
647 #ifdef FEAT_SEARCHPATH
648     case 'f':
649     case 'F':
650     case Ctrl_F:
651 #endif
652 #ifdef FEAT_FIND_ID
653     case 'i':
654     case Ctrl_I:
655     case 'd':
656     case Ctrl_D:
657 #endif
658 		/* window size or any count */
659 		eap->addr_type = ADDR_LINES;
660 		break;
661 
662     case Ctrl_HAT:
663     case '^':
664 		/* buffer number */
665 		eap->addr_type = ADDR_BUFFERS;
666 		break;
667 
668     case Ctrl_Q:
669     case 'q':
670     case Ctrl_C:
671     case 'c':
672     case Ctrl_O:
673     case 'o':
674     case Ctrl_W:
675     case 'w':
676     case 'W':
677     case 'x':
678     case Ctrl_X:
679 		/* window number */
680 		eap->addr_type = ADDR_WINDOWS;
681 		break;
682 
683 #if defined(FEAT_QUICKFIX)
684     case Ctrl_Z:
685     case 'z':
686     case 'P':
687 #endif
688     case 't':
689     case Ctrl_T:
690     case 'b':
691     case Ctrl_B:
692     case 'p':
693     case Ctrl_P:
694     case '=':
695     case CAR:
696 		/* no count */
697 		eap->addr_type = 0;
698 		break;
699     }
700 }
701 
702     static void
703 cmd_with_count(
704     char	*cmd,
705     char_u	*bufp,
706     size_t	bufsize,
707     long	Prenum)
708 {
709     size_t	len = STRLEN(cmd);
710 
711     STRCPY(bufp, cmd);
712     if (Prenum > 0)
713 	vim_snprintf((char *)bufp + len, bufsize - len, "%ld", Prenum);
714 }
715 
716 /*
717  * split the current window, implements CTRL-W s and :split
718  *
719  * "size" is the height or width for the new window, 0 to use half of current
720  * height or width.
721  *
722  * "flags":
723  * WSP_ROOM: require enough room for new window
724  * WSP_VERT: vertical split.
725  * WSP_TOP:  open window at the top-left of the shell (help window).
726  * WSP_BOT:  open window at the bottom-right of the shell (quickfix window).
727  * WSP_HELP: creating the help window, keep layout snapshot
728  *
729  * return FAIL for failure, OK otherwise
730  */
731     int
732 win_split(int size, int flags)
733 {
734     /* When the ":tab" modifier was used open a new tab page instead. */
735     if (may_open_tabpage() == OK)
736 	return OK;
737 
738     /* Add flags from ":vertical", ":topleft" and ":botright". */
739     flags |= cmdmod.split;
740     if ((flags & WSP_TOP) && (flags & WSP_BOT))
741     {
742 	EMSG(_("E442: Can't split topleft and botright at the same time"));
743 	return FAIL;
744     }
745 
746     /* When creating the help window make a snapshot of the window layout.
747      * Otherwise clear the snapshot, it's now invalid. */
748     if (flags & WSP_HELP)
749 	make_snapshot(SNAP_HELP_IDX);
750     else
751 	clear_snapshot(curtab, SNAP_HELP_IDX);
752 
753     return win_split_ins(size, flags, NULL, 0);
754 }
755 
756 /*
757  * When "new_wp" is NULL: split the current window in two.
758  * When "new_wp" is not NULL: insert this window at the far
759  * top/left/right/bottom.
760  * return FAIL for failure, OK otherwise
761  */
762     int
763 win_split_ins(
764     int		size,
765     int		flags,
766     win_T	*new_wp,
767     int		dir)
768 {
769     win_T	*wp = new_wp;
770     win_T	*oldwin;
771     int		new_size = size;
772     int		i;
773     int		need_status = 0;
774     int		do_equal = FALSE;
775     int		needed;
776     int		available;
777     int		oldwin_height = 0;
778     int		layout;
779     frame_T	*frp, *curfrp, *frp2, *prevfrp;
780     int		before;
781     int		minheight;
782     int		wmh1;
783     int		did_set_fraction = FALSE;
784 
785     if (flags & WSP_TOP)
786 	oldwin = firstwin;
787     else if (flags & WSP_BOT)
788 	oldwin = lastwin;
789     else
790 	oldwin = curwin;
791 
792     /* add a status line when p_ls == 1 and splitting the first window */
793     if (ONE_WINDOW && p_ls == 1 && oldwin->w_status_height == 0)
794     {
795 	if (VISIBLE_HEIGHT(oldwin) <= p_wmh && new_wp == NULL)
796 	{
797 	    EMSG(_(e_noroom));
798 	    return FAIL;
799 	}
800 	need_status = STATUS_HEIGHT;
801     }
802 
803 #ifdef FEAT_GUI
804     /* May be needed for the scrollbars that are going to change. */
805     if (gui.in_use)
806 	out_flush();
807 #endif
808 
809     if (flags & WSP_VERT)
810     {
811 	int	wmw1;
812 	int	minwidth;
813 
814 	layout = FR_ROW;
815 
816 	/*
817 	 * Check if we are able to split the current window and compute its
818 	 * width.
819 	 */
820 	/* Current window requires at least 1 space. */
821 	wmw1 = (p_wmw == 0 ? 1 : p_wmw);
822 	needed = wmw1 + 1;
823 	if (flags & WSP_ROOM)
824 	    needed += p_wiw - wmw1;
825 	if (flags & (WSP_BOT | WSP_TOP))
826 	{
827 	    minwidth = frame_minwidth(topframe, NOWIN);
828 	    available = topframe->fr_width;
829 	    needed += minwidth;
830 	}
831 	else if (p_ea)
832 	{
833 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
834 	    prevfrp = oldwin->w_frame;
835 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
836 							frp = frp->fr_parent)
837 	    {
838 		if (frp->fr_layout == FR_ROW)
839 		    for (frp2 = frp->fr_child; frp2 != NULL;
840 							frp2 = frp2->fr_next)
841 			if (frp2 != prevfrp)
842 			    minwidth += frame_minwidth(frp2, NOWIN);
843 		prevfrp = frp;
844 	    }
845 	    available = topframe->fr_width;
846 	    needed += minwidth;
847 	}
848 	else
849 	{
850 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
851 	    available = oldwin->w_frame->fr_width;
852 	    needed += minwidth;
853 	}
854 	if (available < needed && new_wp == NULL)
855 	{
856 	    EMSG(_(e_noroom));
857 	    return FAIL;
858 	}
859 	if (new_size == 0)
860 	    new_size = oldwin->w_width / 2;
861 	if (new_size > available - minwidth - 1)
862 	    new_size = available - minwidth - 1;
863 	if (new_size < wmw1)
864 	    new_size = wmw1;
865 
866 	/* if it doesn't fit in the current window, need win_equal() */
867 	if (oldwin->w_width - new_size - 1 < p_wmw)
868 	    do_equal = TRUE;
869 
870 	/* We don't like to take lines for the new window from a
871 	 * 'winfixwidth' window.  Take them from a window to the left or right
872 	 * instead, if possible. Add one for the separator. */
873 	if (oldwin->w_p_wfw)
874 	    win_setwidth_win(oldwin->w_width + new_size + 1, oldwin);
875 
876 	/* Only make all windows the same width if one of them (except oldwin)
877 	 * is wider than one of the split windows. */
878 	if (!do_equal && p_ea && size == 0 && *p_ead != 'v'
879 	   && oldwin->w_frame->fr_parent != NULL)
880 	{
881 	    frp = oldwin->w_frame->fr_parent->fr_child;
882 	    while (frp != NULL)
883 	    {
884 		if (frp->fr_win != oldwin && frp->fr_win != NULL
885 			&& (frp->fr_win->w_width > new_size
886 			    || frp->fr_win->w_width > oldwin->w_width
887 							      - new_size - 1))
888 		{
889 		    do_equal = TRUE;
890 		    break;
891 		}
892 		frp = frp->fr_next;
893 	    }
894 	}
895     }
896     else
897     {
898 	layout = FR_COL;
899 
900 	/*
901 	 * Check if we are able to split the current window and compute its
902 	 * height.
903 	 */
904 	/* Current window requires at least 1 space. */
905 	wmh1 = (p_wmh == 0 ? 1 : p_wmh) + WINBAR_HEIGHT(curwin);
906 	needed = wmh1 + STATUS_HEIGHT;
907 	if (flags & WSP_ROOM)
908 	    needed += p_wh - wmh1;
909 	if (flags & (WSP_BOT | WSP_TOP))
910 	{
911 	    minheight = frame_minheight(topframe, NOWIN) + need_status;
912 	    available = topframe->fr_height;
913 	    needed += minheight;
914 	}
915 	else if (p_ea)
916 	{
917 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
918 	    prevfrp = oldwin->w_frame;
919 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
920 							frp = frp->fr_parent)
921 	    {
922 		if (frp->fr_layout == FR_COL)
923 		    for (frp2 = frp->fr_child; frp2 != NULL;
924 							frp2 = frp2->fr_next)
925 			if (frp2 != prevfrp)
926 			    minheight += frame_minheight(frp2, NOWIN);
927 		prevfrp = frp;
928 	    }
929 	    available = topframe->fr_height;
930 	    needed += minheight;
931 	}
932 	else
933 	{
934 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
935 	    available = oldwin->w_frame->fr_height;
936 	    needed += minheight;
937 	}
938 	if (available < needed && new_wp == NULL)
939 	{
940 	    EMSG(_(e_noroom));
941 	    return FAIL;
942 	}
943 	oldwin_height = oldwin->w_height;
944 	if (need_status)
945 	{
946 	    oldwin->w_status_height = STATUS_HEIGHT;
947 	    oldwin_height -= STATUS_HEIGHT;
948 	}
949 	if (new_size == 0)
950 	    new_size = oldwin_height / 2;
951 	if (new_size > available - minheight - STATUS_HEIGHT)
952 	    new_size = available - minheight - STATUS_HEIGHT;
953 	if (new_size < wmh1)
954 	    new_size = wmh1;
955 
956 	/* if it doesn't fit in the current window, need win_equal() */
957 	if (oldwin_height - new_size - STATUS_HEIGHT < p_wmh)
958 	    do_equal = TRUE;
959 
960 	/* We don't like to take lines for the new window from a
961 	 * 'winfixheight' window.  Take them from a window above or below
962 	 * instead, if possible. */
963 	if (oldwin->w_p_wfh)
964 	{
965 	    /* Set w_fraction now so that the cursor keeps the same relative
966 	     * vertical position using the old height. */
967 	    set_fraction(oldwin);
968 	    did_set_fraction = TRUE;
969 
970 	    win_setheight_win(oldwin->w_height + new_size + STATUS_HEIGHT,
971 								      oldwin);
972 	    oldwin_height = oldwin->w_height;
973 	    if (need_status)
974 		oldwin_height -= STATUS_HEIGHT;
975 	}
976 
977 	/* Only make all windows the same height if one of them (except oldwin)
978 	 * is higher than one of the split windows. */
979 	if (!do_equal && p_ea && size == 0 && *p_ead != 'h'
980 	   && oldwin->w_frame->fr_parent != NULL)
981 	{
982 	    frp = oldwin->w_frame->fr_parent->fr_child;
983 	    while (frp != NULL)
984 	    {
985 		if (frp->fr_win != oldwin && frp->fr_win != NULL
986 			&& (frp->fr_win->w_height > new_size
987 			    || frp->fr_win->w_height > oldwin_height - new_size
988 							      - STATUS_HEIGHT))
989 		{
990 		    do_equal = TRUE;
991 		    break;
992 		}
993 		frp = frp->fr_next;
994 	    }
995 	}
996     }
997 
998     /*
999      * allocate new window structure and link it in the window list
1000      */
1001     if ((flags & WSP_TOP) == 0
1002 	    && ((flags & WSP_BOT)
1003 		|| (flags & WSP_BELOW)
1004 		|| (!(flags & WSP_ABOVE)
1005 		    && ( (flags & WSP_VERT) ? p_spr : p_sb))))
1006     {
1007 	/* new window below/right of current one */
1008 	if (new_wp == NULL)
1009 	    wp = win_alloc(oldwin, FALSE);
1010 	else
1011 	    win_append(oldwin, wp);
1012     }
1013     else
1014     {
1015 	if (new_wp == NULL)
1016 	    wp = win_alloc(oldwin->w_prev, FALSE);
1017 	else
1018 	    win_append(oldwin->w_prev, wp);
1019     }
1020 
1021     if (new_wp == NULL)
1022     {
1023 	if (wp == NULL)
1024 	    return FAIL;
1025 
1026 	new_frame(wp);
1027 	if (wp->w_frame == NULL)
1028 	{
1029 	    win_free(wp, NULL);
1030 	    return FAIL;
1031 	}
1032 
1033 	/* make the contents of the new window the same as the current one */
1034 	win_init(wp, curwin, flags);
1035     }
1036 
1037     /*
1038      * Reorganise the tree of frames to insert the new window.
1039      */
1040     if (flags & (WSP_TOP | WSP_BOT))
1041     {
1042 	if ((topframe->fr_layout == FR_COL && (flags & WSP_VERT) == 0)
1043 	    || (topframe->fr_layout == FR_ROW && (flags & WSP_VERT) != 0))
1044 	{
1045 	    curfrp = topframe->fr_child;
1046 	    if (flags & WSP_BOT)
1047 		while (curfrp->fr_next != NULL)
1048 		    curfrp = curfrp->fr_next;
1049 	}
1050 	else
1051 	    curfrp = topframe;
1052 	before = (flags & WSP_TOP);
1053     }
1054     else
1055     {
1056 	curfrp = oldwin->w_frame;
1057 	if (flags & WSP_BELOW)
1058 	    before = FALSE;
1059 	else if (flags & WSP_ABOVE)
1060 	    before = TRUE;
1061 	else if (flags & WSP_VERT)
1062 	    before = !p_spr;
1063 	else
1064 	    before = !p_sb;
1065     }
1066     if (curfrp->fr_parent == NULL || curfrp->fr_parent->fr_layout != layout)
1067     {
1068 	/* Need to create a new frame in the tree to make a branch. */
1069 	frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
1070 	*frp = *curfrp;
1071 	curfrp->fr_layout = layout;
1072 	frp->fr_parent = curfrp;
1073 	frp->fr_next = NULL;
1074 	frp->fr_prev = NULL;
1075 	curfrp->fr_child = frp;
1076 	curfrp->fr_win = NULL;
1077 	curfrp = frp;
1078 	if (frp->fr_win != NULL)
1079 	    oldwin->w_frame = frp;
1080 	else
1081 	    for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
1082 		frp->fr_parent = curfrp;
1083     }
1084 
1085     if (new_wp == NULL)
1086 	frp = wp->w_frame;
1087     else
1088 	frp = new_wp->w_frame;
1089     frp->fr_parent = curfrp->fr_parent;
1090 
1091     /* Insert the new frame at the right place in the frame list. */
1092     if (before)
1093 	frame_insert(curfrp, frp);
1094     else
1095 	frame_append(curfrp, frp);
1096 
1097     /* Set w_fraction now so that the cursor keeps the same relative
1098      * vertical position. */
1099     if (!did_set_fraction)
1100 	set_fraction(oldwin);
1101     wp->w_fraction = oldwin->w_fraction;
1102 
1103     if (flags & WSP_VERT)
1104     {
1105 	wp->w_p_scr = curwin->w_p_scr;
1106 
1107 	if (need_status)
1108 	{
1109 	    win_new_height(oldwin, oldwin->w_height - 1);
1110 	    oldwin->w_status_height = need_status;
1111 	}
1112 	if (flags & (WSP_TOP | WSP_BOT))
1113 	{
1114 	    /* set height and row of new window to full height */
1115 	    wp->w_winrow = tabline_height();
1116 	    win_new_height(wp, curfrp->fr_height - (p_ls > 0)
1117 							  - WINBAR_HEIGHT(wp));
1118 	    wp->w_status_height = (p_ls > 0);
1119 	}
1120 	else
1121 	{
1122 	    /* height and row of new window is same as current window */
1123 	    wp->w_winrow = oldwin->w_winrow;
1124 	    win_new_height(wp, VISIBLE_HEIGHT(oldwin));
1125 	    wp->w_status_height = oldwin->w_status_height;
1126 	}
1127 	frp->fr_height = curfrp->fr_height;
1128 
1129 	/* "new_size" of the current window goes to the new window, use
1130 	 * one column for the vertical separator */
1131 	win_new_width(wp, new_size);
1132 	if (before)
1133 	    wp->w_vsep_width = 1;
1134 	else
1135 	{
1136 	    wp->w_vsep_width = oldwin->w_vsep_width;
1137 	    oldwin->w_vsep_width = 1;
1138 	}
1139 	if (flags & (WSP_TOP | WSP_BOT))
1140 	{
1141 	    if (flags & WSP_BOT)
1142 		frame_add_vsep(curfrp);
1143 	    /* Set width of neighbor frame */
1144 	    frame_new_width(curfrp, curfrp->fr_width
1145 		     - (new_size + ((flags & WSP_TOP) != 0)), flags & WSP_TOP,
1146 								       FALSE);
1147 	}
1148 	else
1149 	    win_new_width(oldwin, oldwin->w_width - (new_size + 1));
1150 	if (before)	/* new window left of current one */
1151 	{
1152 	    wp->w_wincol = oldwin->w_wincol;
1153 	    oldwin->w_wincol += new_size + 1;
1154 	}
1155 	else		/* new window right of current one */
1156 	    wp->w_wincol = oldwin->w_wincol + oldwin->w_width + 1;
1157 	frame_fix_width(oldwin);
1158 	frame_fix_width(wp);
1159     }
1160     else
1161     {
1162 	/* width and column of new window is same as current window */
1163 	if (flags & (WSP_TOP | WSP_BOT))
1164 	{
1165 	    wp->w_wincol = 0;
1166 	    win_new_width(wp, Columns);
1167 	    wp->w_vsep_width = 0;
1168 	}
1169 	else
1170 	{
1171 	    wp->w_wincol = oldwin->w_wincol;
1172 	    win_new_width(wp, oldwin->w_width);
1173 	    wp->w_vsep_width = oldwin->w_vsep_width;
1174 	}
1175 	frp->fr_width = curfrp->fr_width;
1176 
1177 	/* "new_size" of the current window goes to the new window, use
1178 	 * one row for the status line */
1179 	win_new_height(wp, new_size);
1180 	if (flags & (WSP_TOP | WSP_BOT))
1181 	{
1182 	    int new_fr_height = curfrp->fr_height - new_size
1183 							  + WINBAR_HEIGHT(wp) ;
1184 
1185 	    if (!((flags & WSP_BOT) && p_ls == 0))
1186 		new_fr_height -= STATUS_HEIGHT;
1187 	    frame_new_height(curfrp, new_fr_height, flags & WSP_TOP, FALSE);
1188 	}
1189 	else
1190 	    win_new_height(oldwin, oldwin_height - (new_size + STATUS_HEIGHT));
1191 	if (before)	/* new window above current one */
1192 	{
1193 	    wp->w_winrow = oldwin->w_winrow;
1194 	    wp->w_status_height = STATUS_HEIGHT;
1195 	    oldwin->w_winrow += wp->w_height + STATUS_HEIGHT;
1196 	}
1197 	else		/* new window below current one */
1198 	{
1199 	    wp->w_winrow = oldwin->w_winrow + VISIBLE_HEIGHT(oldwin)
1200 							       + STATUS_HEIGHT;
1201 	    wp->w_status_height = oldwin->w_status_height;
1202 	    if (!(flags & WSP_BOT))
1203 		oldwin->w_status_height = STATUS_HEIGHT;
1204 	}
1205 	if (flags & WSP_BOT)
1206 	    frame_add_statusline(curfrp);
1207 	frame_fix_height(wp);
1208 	frame_fix_height(oldwin);
1209     }
1210 
1211     if (flags & (WSP_TOP | WSP_BOT))
1212 	(void)win_comp_pos();
1213 
1214     /*
1215      * Both windows need redrawing
1216      */
1217     redraw_win_later(wp, NOT_VALID);
1218     wp->w_redr_status = TRUE;
1219     redraw_win_later(oldwin, NOT_VALID);
1220     oldwin->w_redr_status = TRUE;
1221 
1222     if (need_status)
1223     {
1224 	msg_row = Rows - 1;
1225 	msg_col = sc_col;
1226 	msg_clr_eos_force();	/* Old command/ruler may still be there */
1227 	comp_col();
1228 	msg_row = Rows - 1;
1229 	msg_col = 0;	/* put position back at start of line */
1230     }
1231 
1232     /*
1233      * equalize the window sizes.
1234      */
1235     if (do_equal || dir != 0)
1236 	win_equal(wp, TRUE,
1237 		(flags & WSP_VERT) ? (dir == 'v' ? 'b' : 'h')
1238 		: dir == 'h' ? 'b' : 'v');
1239 
1240     /* Don't change the window height/width to 'winheight' / 'winwidth' if a
1241      * size was given. */
1242     if (flags & WSP_VERT)
1243     {
1244 	i = p_wiw;
1245 	if (size != 0)
1246 	    p_wiw = size;
1247 
1248 # ifdef FEAT_GUI
1249 	/* When 'guioptions' includes 'L' or 'R' may have to add scrollbars. */
1250 	if (gui.in_use)
1251 	    gui_init_which_components(NULL);
1252 # endif
1253     }
1254     else
1255     {
1256 	i = p_wh;
1257 	if (size != 0)
1258 	    p_wh = size;
1259     }
1260 
1261 #ifdef FEAT_JUMPLIST
1262     /* Keep same changelist position in new window. */
1263     wp->w_changelistidx = oldwin->w_changelistidx;
1264 #endif
1265 
1266     /*
1267      * make the new window the current window
1268      */
1269     win_enter_ext(wp, FALSE, FALSE, TRUE, TRUE, TRUE);
1270     if (flags & WSP_VERT)
1271 	p_wiw = i;
1272     else
1273 	p_wh = i;
1274 
1275     return OK;
1276 }
1277 
1278 
1279 /*
1280  * Initialize window "newp" from window "oldp".
1281  * Used when splitting a window and when creating a new tab page.
1282  * The windows will both edit the same buffer.
1283  * WSP_NEWLOC may be specified in flags to prevent the location list from
1284  * being copied.
1285  */
1286     static void
1287 win_init(win_T *newp, win_T *oldp, int flags UNUSED)
1288 {
1289     int		i;
1290 
1291     newp->w_buffer = oldp->w_buffer;
1292 #ifdef FEAT_SYN_HL
1293     newp->w_s = &(oldp->w_buffer->b_s);
1294 #endif
1295     oldp->w_buffer->b_nwindows++;
1296     newp->w_cursor = oldp->w_cursor;
1297     newp->w_valid = 0;
1298     newp->w_curswant = oldp->w_curswant;
1299     newp->w_set_curswant = oldp->w_set_curswant;
1300     newp->w_topline = oldp->w_topline;
1301 #ifdef FEAT_DIFF
1302     newp->w_topfill = oldp->w_topfill;
1303 #endif
1304     newp->w_leftcol = oldp->w_leftcol;
1305     newp->w_pcmark = oldp->w_pcmark;
1306     newp->w_prev_pcmark = oldp->w_prev_pcmark;
1307     newp->w_alt_fnum = oldp->w_alt_fnum;
1308     newp->w_wrow = oldp->w_wrow;
1309     newp->w_fraction = oldp->w_fraction;
1310     newp->w_prev_fraction_row = oldp->w_prev_fraction_row;
1311 #ifdef FEAT_JUMPLIST
1312     copy_jumplist(oldp, newp);
1313 #endif
1314 #ifdef FEAT_QUICKFIX
1315     if (flags & WSP_NEWLOC)
1316     {
1317 	/* Don't copy the location list.  */
1318 	newp->w_llist = NULL;
1319 	newp->w_llist_ref = NULL;
1320     }
1321     else
1322 	copy_loclist_stack(oldp, newp);
1323 #endif
1324     newp->w_localdir = (oldp->w_localdir == NULL)
1325 				    ? NULL : vim_strsave(oldp->w_localdir);
1326 
1327     /* copy tagstack and folds */
1328     for (i = 0; i < oldp->w_tagstacklen; i++)
1329     {
1330 	newp->w_tagstack[i] = oldp->w_tagstack[i];
1331 	if (newp->w_tagstack[i].tagname != NULL)
1332 	    newp->w_tagstack[i].tagname =
1333 				   vim_strsave(newp->w_tagstack[i].tagname);
1334     }
1335     newp->w_tagstackidx = oldp->w_tagstackidx;
1336     newp->w_tagstacklen = oldp->w_tagstacklen;
1337 #ifdef FEAT_FOLDING
1338     copyFoldingState(oldp, newp);
1339 #endif
1340 
1341     win_init_some(newp, oldp);
1342 
1343 #ifdef FEAT_SYN_HL
1344     check_colorcolumn(newp);
1345 #endif
1346 }
1347 
1348 /*
1349  * Initialize window "newp" from window "old".
1350  * Only the essential things are copied.
1351  */
1352     static void
1353 win_init_some(win_T *newp, win_T *oldp)
1354 {
1355     /* Use the same argument list. */
1356     newp->w_alist = oldp->w_alist;
1357     ++newp->w_alist->al_refcount;
1358     newp->w_arg_idx = oldp->w_arg_idx;
1359 
1360     /* copy options from existing window */
1361     win_copy_options(oldp, newp);
1362 }
1363 
1364 
1365 /*
1366  * Check if "win" is a pointer to an existing window in the current tab page.
1367  */
1368     int
1369 win_valid(win_T *win)
1370 {
1371     win_T	*wp;
1372 
1373     if (win == NULL)
1374 	return FALSE;
1375     FOR_ALL_WINDOWS(wp)
1376 	if (wp == win)
1377 	    return TRUE;
1378     return FALSE;
1379 }
1380 
1381 /*
1382  * Check if "win" is a pointer to an existing window in any tab page.
1383  */
1384     int
1385 win_valid_any_tab(win_T *win)
1386 {
1387     win_T	*wp;
1388     tabpage_T	*tp;
1389 
1390     if (win == NULL)
1391 	return FALSE;
1392     FOR_ALL_TABPAGES(tp)
1393     {
1394 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
1395 	{
1396 	    if (wp == win)
1397 		return TRUE;
1398 	}
1399     }
1400     return FALSE;
1401 }
1402 
1403 /*
1404  * Return the number of windows.
1405  */
1406     int
1407 win_count(void)
1408 {
1409     win_T	*wp;
1410     int		count = 0;
1411 
1412     FOR_ALL_WINDOWS(wp)
1413 	++count;
1414     return count;
1415 }
1416 
1417 /*
1418  * Make "count" windows on the screen.
1419  * Return actual number of windows on the screen.
1420  * Must be called when there is just one window, filling the whole screen
1421  * (excluding the command line).
1422  */
1423     int
1424 make_windows(
1425     int		count,
1426     int		vertical UNUSED)  /* split windows vertically if TRUE */
1427 {
1428     int		maxcount;
1429     int		todo;
1430 
1431     if (vertical)
1432     {
1433 	/* Each windows needs at least 'winminwidth' lines and a separator
1434 	 * column. */
1435 	maxcount = (curwin->w_width + curwin->w_vsep_width
1436 					     - (p_wiw - p_wmw)) / (p_wmw + 1);
1437     }
1438     else
1439     {
1440 	/* Each window needs at least 'winminheight' lines and a status line. */
1441 	maxcount = (VISIBLE_HEIGHT(curwin) + curwin->w_status_height
1442 				  - (p_wh - p_wmh)) / (p_wmh + STATUS_HEIGHT);
1443     }
1444 
1445     if (maxcount < 2)
1446 	maxcount = 2;
1447     if (count > maxcount)
1448 	count = maxcount;
1449 
1450     /*
1451      * add status line now, otherwise first window will be too big
1452      */
1453     if (count > 1)
1454 	last_status(TRUE);
1455 
1456     /*
1457      * Don't execute autocommands while creating the windows.  Must do that
1458      * when putting the buffers in the windows.
1459      */
1460     block_autocmds();
1461 
1462     /* todo is number of windows left to create */
1463     for (todo = count - 1; todo > 0; --todo)
1464 	if (vertical)
1465 	{
1466 	    if (win_split(curwin->w_width - (curwin->w_width - todo)
1467 			/ (todo + 1) - 1, WSP_VERT | WSP_ABOVE) == FAIL)
1468 		break;
1469 	}
1470 	else
1471 	{
1472 	    if (win_split(curwin->w_height - (curwin->w_height - todo
1473 			    * STATUS_HEIGHT) / (todo + 1)
1474 			- STATUS_HEIGHT, WSP_ABOVE) == FAIL)
1475 		break;
1476 	}
1477 
1478     unblock_autocmds();
1479 
1480     /* return actual number of windows */
1481     return (count - todo);
1482 }
1483 
1484 /*
1485  * Exchange current and next window
1486  */
1487     static void
1488 win_exchange(long Prenum)
1489 {
1490     frame_T	*frp;
1491     frame_T	*frp2;
1492     win_T	*wp;
1493     win_T	*wp2;
1494     int		temp;
1495 
1496     if (ONE_WINDOW)	    /* just one window */
1497     {
1498 	beep_flush();
1499 	return;
1500     }
1501 
1502 #ifdef FEAT_GUI
1503     need_mouse_correct = TRUE;
1504 #endif
1505 
1506     /*
1507      * find window to exchange with
1508      */
1509     if (Prenum)
1510     {
1511 	frp = curwin->w_frame->fr_parent->fr_child;
1512 	while (frp != NULL && --Prenum > 0)
1513 	    frp = frp->fr_next;
1514     }
1515     else if (curwin->w_frame->fr_next != NULL)	/* Swap with next */
1516 	frp = curwin->w_frame->fr_next;
1517     else    /* Swap last window in row/col with previous */
1518 	frp = curwin->w_frame->fr_prev;
1519 
1520     /* We can only exchange a window with another window, not with a frame
1521      * containing windows. */
1522     if (frp == NULL || frp->fr_win == NULL || frp->fr_win == curwin)
1523 	return;
1524     wp = frp->fr_win;
1525 
1526 /*
1527  * 1. remove curwin from the list. Remember after which window it was in wp2
1528  * 2. insert curwin before wp in the list
1529  * if wp != wp2
1530  *    3. remove wp from the list
1531  *    4. insert wp after wp2
1532  * 5. exchange the status line height and vsep width.
1533  */
1534     wp2 = curwin->w_prev;
1535     frp2 = curwin->w_frame->fr_prev;
1536     if (wp->w_prev != curwin)
1537     {
1538 	win_remove(curwin, NULL);
1539 	frame_remove(curwin->w_frame);
1540 	win_append(wp->w_prev, curwin);
1541 	frame_insert(frp, curwin->w_frame);
1542     }
1543     if (wp != wp2)
1544     {
1545 	win_remove(wp, NULL);
1546 	frame_remove(wp->w_frame);
1547 	win_append(wp2, wp);
1548 	if (frp2 == NULL)
1549 	    frame_insert(wp->w_frame->fr_parent->fr_child, wp->w_frame);
1550 	else
1551 	    frame_append(frp2, wp->w_frame);
1552     }
1553     temp = curwin->w_status_height;
1554     curwin->w_status_height = wp->w_status_height;
1555     wp->w_status_height = temp;
1556     temp = curwin->w_vsep_width;
1557     curwin->w_vsep_width = wp->w_vsep_width;
1558     wp->w_vsep_width = temp;
1559 
1560     /* If the windows are not in the same frame, exchange the sizes to avoid
1561      * messing up the window layout.  Otherwise fix the frame sizes. */
1562     if (curwin->w_frame->fr_parent != wp->w_frame->fr_parent)
1563     {
1564 	temp = curwin->w_height;
1565 	curwin->w_height = wp->w_height;
1566 	wp->w_height = temp;
1567 	temp = curwin->w_width;
1568 	curwin->w_width = wp->w_width;
1569 	wp->w_width = temp;
1570     }
1571     else
1572     {
1573 	frame_fix_height(curwin);
1574 	frame_fix_height(wp);
1575 	frame_fix_width(curwin);
1576 	frame_fix_width(wp);
1577     }
1578 
1579     (void)win_comp_pos();		/* recompute window positions */
1580 
1581     win_enter(wp, TRUE);
1582     redraw_later(CLEAR);
1583 }
1584 
1585 /*
1586  * rotate windows: if upwards TRUE the second window becomes the first one
1587  *		   if upwards FALSE the first window becomes the second one
1588  */
1589     static void
1590 win_rotate(int upwards, int count)
1591 {
1592     win_T	*wp1;
1593     win_T	*wp2;
1594     frame_T	*frp;
1595     int		n;
1596 
1597     if (ONE_WINDOW)		/* nothing to do */
1598     {
1599 	beep_flush();
1600 	return;
1601     }
1602 
1603 #ifdef FEAT_GUI
1604     need_mouse_correct = TRUE;
1605 #endif
1606 
1607     /* Check if all frames in this row/col have one window. */
1608     for (frp = curwin->w_frame->fr_parent->fr_child; frp != NULL;
1609 							   frp = frp->fr_next)
1610 	if (frp->fr_win == NULL)
1611 	{
1612 	    EMSG(_("E443: Cannot rotate when another window is split"));
1613 	    return;
1614 	}
1615 
1616     while (count--)
1617     {
1618 	if (upwards)		/* first window becomes last window */
1619 	{
1620 	    /* remove first window/frame from the list */
1621 	    frp = curwin->w_frame->fr_parent->fr_child;
1622 	    wp1 = frp->fr_win;
1623 	    win_remove(wp1, NULL);
1624 	    frame_remove(frp);
1625 
1626 	    /* find last frame and append removed window/frame after it */
1627 	    for ( ; frp->fr_next != NULL; frp = frp->fr_next)
1628 		;
1629 	    win_append(frp->fr_win, wp1);
1630 	    frame_append(frp, wp1->w_frame);
1631 
1632 	    wp2 = frp->fr_win;		/* previously last window */
1633 	}
1634 	else			/* last window becomes first window */
1635 	{
1636 	    /* find last window/frame in the list and remove it */
1637 	    for (frp = curwin->w_frame; frp->fr_next != NULL;
1638 							   frp = frp->fr_next)
1639 		;
1640 	    wp1 = frp->fr_win;
1641 	    wp2 = wp1->w_prev;		    /* will become last window */
1642 	    win_remove(wp1, NULL);
1643 	    frame_remove(frp);
1644 
1645 	    /* append the removed window/frame before the first in the list */
1646 	    win_append(frp->fr_parent->fr_child->fr_win->w_prev, wp1);
1647 	    frame_insert(frp->fr_parent->fr_child, frp);
1648 	}
1649 
1650 	/* exchange status height and vsep width of old and new last window */
1651 	n = wp2->w_status_height;
1652 	wp2->w_status_height = wp1->w_status_height;
1653 	wp1->w_status_height = n;
1654 	frame_fix_height(wp1);
1655 	frame_fix_height(wp2);
1656 	n = wp2->w_vsep_width;
1657 	wp2->w_vsep_width = wp1->w_vsep_width;
1658 	wp1->w_vsep_width = n;
1659 	frame_fix_width(wp1);
1660 	frame_fix_width(wp2);
1661 
1662 	/* recompute w_winrow and w_wincol for all windows */
1663 	(void)win_comp_pos();
1664     }
1665 
1666     redraw_later(CLEAR);
1667 }
1668 
1669 /*
1670  * Move the current window to the very top/bottom/left/right of the screen.
1671  */
1672     static void
1673 win_totop(int size, int flags)
1674 {
1675     int		dir;
1676     int		height = curwin->w_height;
1677 
1678     if (ONE_WINDOW)
1679     {
1680 	beep_flush();
1681 	return;
1682     }
1683 
1684     /* Remove the window and frame from the tree of frames. */
1685     (void)winframe_remove(curwin, &dir, NULL);
1686     win_remove(curwin, NULL);
1687     last_status(FALSE);	    /* may need to remove last status line */
1688     (void)win_comp_pos();   /* recompute window positions */
1689 
1690     /* Split a window on the desired side and put the window there. */
1691     (void)win_split_ins(size, flags, curwin, dir);
1692     if (!(flags & WSP_VERT))
1693     {
1694 	win_setheight(height);
1695 	if (p_ea)
1696 	    win_equal(curwin, TRUE, 'v');
1697     }
1698 
1699 #if defined(FEAT_GUI)
1700     /* When 'guioptions' includes 'L' or 'R' may have to remove or add
1701      * scrollbars.  Have to update them anyway. */
1702     gui_may_update_scrollbars();
1703 #endif
1704 }
1705 
1706 /*
1707  * Move window "win1" to below/right of "win2" and make "win1" the current
1708  * window.  Only works within the same frame!
1709  */
1710     void
1711 win_move_after(win_T *win1, win_T *win2)
1712 {
1713     int		height;
1714 
1715     /* check if the arguments are reasonable */
1716     if (win1 == win2)
1717 	return;
1718 
1719     /* check if there is something to do */
1720     if (win2->w_next != win1)
1721     {
1722 	/* may need move the status line/vertical separator of the last window
1723 	 * */
1724 	if (win1 == lastwin)
1725 	{
1726 	    height = win1->w_prev->w_status_height;
1727 	    win1->w_prev->w_status_height = win1->w_status_height;
1728 	    win1->w_status_height = height;
1729 	    if (win1->w_prev->w_vsep_width == 1)
1730 	    {
1731 		/* Remove the vertical separator from the last-but-one window,
1732 		 * add it to the last window.  Adjust the frame widths. */
1733 		win1->w_prev->w_vsep_width = 0;
1734 		win1->w_prev->w_frame->fr_width -= 1;
1735 		win1->w_vsep_width = 1;
1736 		win1->w_frame->fr_width += 1;
1737 	    }
1738 	}
1739 	else if (win2 == lastwin)
1740 	{
1741 	    height = win1->w_status_height;
1742 	    win1->w_status_height = win2->w_status_height;
1743 	    win2->w_status_height = height;
1744 	    if (win1->w_vsep_width == 1)
1745 	    {
1746 		/* Remove the vertical separator from win1, add it to the last
1747 		 * window, win2.  Adjust the frame widths. */
1748 		win2->w_vsep_width = 1;
1749 		win2->w_frame->fr_width += 1;
1750 		win1->w_vsep_width = 0;
1751 		win1->w_frame->fr_width -= 1;
1752 	    }
1753 	}
1754 	win_remove(win1, NULL);
1755 	frame_remove(win1->w_frame);
1756 	win_append(win2, win1);
1757 	frame_append(win2->w_frame, win1->w_frame);
1758 
1759 	(void)win_comp_pos();	/* recompute w_winrow for all windows */
1760 	redraw_later(NOT_VALID);
1761     }
1762     win_enter(win1, FALSE);
1763 }
1764 
1765 /*
1766  * Make all windows the same height.
1767  * 'next_curwin' will soon be the current window, make sure it has enough
1768  * rows.
1769  */
1770     void
1771 win_equal(
1772     win_T	*next_curwin,	/* pointer to current window to be or NULL */
1773     int		current,	/* do only frame with current window */
1774     int		dir)		/* 'v' for vertically, 'h' for horizontally,
1775 				   'b' for both, 0 for using p_ead */
1776 {
1777     if (dir == 0)
1778 	dir = *p_ead;
1779     win_equal_rec(next_curwin == NULL ? curwin : next_curwin, current,
1780 		      topframe, dir, 0, tabline_height(),
1781 					   (int)Columns, topframe->fr_height);
1782 }
1783 
1784 /*
1785  * Set a frame to a new position and height, spreading the available room
1786  * equally over contained frames.
1787  * The window "next_curwin" (if not NULL) should at least get the size from
1788  * 'winheight' and 'winwidth' if possible.
1789  */
1790     static void
1791 win_equal_rec(
1792     win_T	*next_curwin,	/* pointer to current window to be or NULL */
1793     int		current,	/* do only frame with current window */
1794     frame_T	*topfr,		/* frame to set size off */
1795     int		dir,		/* 'v', 'h' or 'b', see win_equal() */
1796     int		col,		/* horizontal position for frame */
1797     int		row,		/* vertical position for frame */
1798     int		width,		/* new width of frame */
1799     int		height)		/* new height of frame */
1800 {
1801     int		n, m;
1802     int		extra_sep = 0;
1803     int		wincount, totwincount = 0;
1804     frame_T	*fr;
1805     int		next_curwin_size = 0;
1806     int		room = 0;
1807     int		new_size;
1808     int		has_next_curwin = 0;
1809     int		hnc;
1810 
1811     if (topfr->fr_layout == FR_LEAF)
1812     {
1813 	/* Set the width/height of this frame.
1814 	 * Redraw when size or position changes */
1815 	if (topfr->fr_height != height || topfr->fr_win->w_winrow != row
1816 		|| topfr->fr_width != width || topfr->fr_win->w_wincol != col
1817 	   )
1818 	{
1819 	    topfr->fr_win->w_winrow = row;
1820 	    frame_new_height(topfr, height, FALSE, FALSE);
1821 	    topfr->fr_win->w_wincol = col;
1822 	    frame_new_width(topfr, width, FALSE, FALSE);
1823 	    redraw_all_later(CLEAR);
1824 	}
1825     }
1826     else if (topfr->fr_layout == FR_ROW)
1827     {
1828 	topfr->fr_width = width;
1829 	topfr->fr_height = height;
1830 
1831 	if (dir != 'v')			/* equalize frame widths */
1832 	{
1833 	    /* Compute the maximum number of windows horizontally in this
1834 	     * frame. */
1835 	    n = frame_minwidth(topfr, NOWIN);
1836 	    /* add one for the rightmost window, it doesn't have a separator */
1837 	    if (col + width == Columns)
1838 		extra_sep = 1;
1839 	    else
1840 		extra_sep = 0;
1841 	    totwincount = (n + extra_sep) / (p_wmw + 1);
1842 	    has_next_curwin = frame_has_win(topfr, next_curwin);
1843 
1844 	    /*
1845 	     * Compute width for "next_curwin" window and room available for
1846 	     * other windows.
1847 	     * "m" is the minimal width when counting p_wiw for "next_curwin".
1848 	     */
1849 	    m = frame_minwidth(topfr, next_curwin);
1850 	    room = width - m;
1851 	    if (room < 0)
1852 	    {
1853 		next_curwin_size = p_wiw + room;
1854 		room = 0;
1855 	    }
1856 	    else
1857 	    {
1858 		next_curwin_size = -1;
1859 		for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
1860 		{
1861 		    /* If 'winfixwidth' set keep the window width if
1862 		     * possible.
1863 		     * Watch out for this window being the next_curwin. */
1864 		    if (frame_fixed_width(fr))
1865 		    {
1866 			n = frame_minwidth(fr, NOWIN);
1867 			new_size = fr->fr_width;
1868 			if (frame_has_win(fr, next_curwin))
1869 			{
1870 			    room += p_wiw - p_wmw;
1871 			    next_curwin_size = 0;
1872 			    if (new_size < p_wiw)
1873 				new_size = p_wiw;
1874 			}
1875 			else
1876 			    /* These windows don't use up room. */
1877 			    totwincount -= (n + (fr->fr_next == NULL
1878 					      ? extra_sep : 0)) / (p_wmw + 1);
1879 			room -= new_size - n;
1880 			if (room < 0)
1881 			{
1882 			    new_size += room;
1883 			    room = 0;
1884 			}
1885 			fr->fr_newwidth = new_size;
1886 		    }
1887 		}
1888 		if (next_curwin_size == -1)
1889 		{
1890 		    if (!has_next_curwin)
1891 			next_curwin_size = 0;
1892 		    else if (totwincount > 1
1893 			    && (room + (totwincount - 2))
1894 						  / (totwincount - 1) > p_wiw)
1895 		    {
1896 			/* Can make all windows wider than 'winwidth', spread
1897 			 * the room equally. */
1898 			next_curwin_size = (room + p_wiw
1899 					    + (totwincount - 1) * p_wmw
1900 					    + (totwincount - 1)) / totwincount;
1901 			room -= next_curwin_size - p_wiw;
1902 		    }
1903 		    else
1904 			next_curwin_size = p_wiw;
1905 		}
1906 	    }
1907 
1908 	    if (has_next_curwin)
1909 		--totwincount;		/* don't count curwin */
1910 	}
1911 
1912 	for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
1913 	{
1914 	    wincount = 1;
1915 	    if (fr->fr_next == NULL)
1916 		/* last frame gets all that remains (avoid roundoff error) */
1917 		new_size = width;
1918 	    else if (dir == 'v')
1919 		new_size = fr->fr_width;
1920 	    else if (frame_fixed_width(fr))
1921 	    {
1922 		new_size = fr->fr_newwidth;
1923 		wincount = 0;	    /* doesn't count as a sizeable window */
1924 	    }
1925 	    else
1926 	    {
1927 		/* Compute the maximum number of windows horiz. in "fr". */
1928 		n = frame_minwidth(fr, NOWIN);
1929 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
1930 								/ (p_wmw + 1);
1931 		m = frame_minwidth(fr, next_curwin);
1932 		if (has_next_curwin)
1933 		    hnc = frame_has_win(fr, next_curwin);
1934 		else
1935 		    hnc = FALSE;
1936 		if (hnc)	    /* don't count next_curwin */
1937 		    --wincount;
1938 		if (totwincount == 0)
1939 		    new_size = room;
1940 		else
1941 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
1942 								/ totwincount;
1943 		if (hnc)	    /* add next_curwin size */
1944 		{
1945 		    next_curwin_size -= p_wiw - (m - n);
1946 		    new_size += next_curwin_size;
1947 		    room -= new_size - next_curwin_size;
1948 		}
1949 		else
1950 		    room -= new_size;
1951 		new_size += n;
1952 	    }
1953 
1954 	    /* Skip frame that is full width when splitting or closing a
1955 	     * window, unless equalizing all frames. */
1956 	    if (!current || dir != 'v' || topfr->fr_parent != NULL
1957 		    || (new_size != fr->fr_width)
1958 		    || frame_has_win(fr, next_curwin))
1959 		win_equal_rec(next_curwin, current, fr, dir, col, row,
1960 							    new_size, height);
1961 	    col += new_size;
1962 	    width -= new_size;
1963 	    totwincount -= wincount;
1964 	}
1965     }
1966     else /* topfr->fr_layout == FR_COL */
1967     {
1968 	topfr->fr_width = width;
1969 	topfr->fr_height = height;
1970 
1971 	if (dir != 'h')			/* equalize frame heights */
1972 	{
1973 	    /* Compute maximum number of windows vertically in this frame. */
1974 	    n = frame_minheight(topfr, NOWIN);
1975 	    /* add one for the bottom window if it doesn't have a statusline */
1976 	    if (row + height == cmdline_row && p_ls == 0)
1977 		extra_sep = 1;
1978 	    else
1979 		extra_sep = 0;
1980 	    totwincount = (n + extra_sep) / (p_wmh + 1);
1981 	    has_next_curwin = frame_has_win(topfr, next_curwin);
1982 
1983 	    /*
1984 	     * Compute height for "next_curwin" window and room available for
1985 	     * other windows.
1986 	     * "m" is the minimal height when counting p_wh for "next_curwin".
1987 	     */
1988 	    m = frame_minheight(topfr, next_curwin);
1989 	    room = height - m;
1990 	    if (room < 0)
1991 	    {
1992 		/* The room is less then 'winheight', use all space for the
1993 		 * current window. */
1994 		next_curwin_size = p_wh + room;
1995 		room = 0;
1996 	    }
1997 	    else
1998 	    {
1999 		next_curwin_size = -1;
2000 		for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
2001 		{
2002 		    /* If 'winfixheight' set keep the window height if
2003 		     * possible.
2004 		     * Watch out for this window being the next_curwin. */
2005 		    if (frame_fixed_height(fr))
2006 		    {
2007 			n = frame_minheight(fr, NOWIN);
2008 			new_size = fr->fr_height;
2009 			if (frame_has_win(fr, next_curwin))
2010 			{
2011 			    room += p_wh - p_wmh;
2012 			    next_curwin_size = 0;
2013 			    if (new_size < p_wh)
2014 				new_size = p_wh;
2015 			}
2016 			else
2017 			    /* These windows don't use up room. */
2018 			    totwincount -= (n + (fr->fr_next == NULL
2019 					      ? extra_sep : 0)) / (p_wmh + 1);
2020 			room -= new_size - n;
2021 			if (room < 0)
2022 			{
2023 			    new_size += room;
2024 			    room = 0;
2025 			}
2026 			fr->fr_newheight = new_size;
2027 		    }
2028 		}
2029 		if (next_curwin_size == -1)
2030 		{
2031 		    if (!has_next_curwin)
2032 			next_curwin_size = 0;
2033 		    else if (totwincount > 1
2034 			    && (room + (totwincount - 2))
2035 						   / (totwincount - 1) > p_wh)
2036 		    {
2037 			/* can make all windows higher than 'winheight',
2038 			 * spread the room equally. */
2039 			next_curwin_size = (room + p_wh
2040 					   + (totwincount - 1) * p_wmh
2041 					   + (totwincount - 1)) / totwincount;
2042 			room -= next_curwin_size - p_wh;
2043 		    }
2044 		    else
2045 			next_curwin_size = p_wh;
2046 		}
2047 	    }
2048 
2049 	    if (has_next_curwin)
2050 		--totwincount;		/* don't count curwin */
2051 	}
2052 
2053 	for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
2054 	{
2055 	    wincount = 1;
2056 	    if (fr->fr_next == NULL)
2057 		/* last frame gets all that remains (avoid roundoff error) */
2058 		new_size = height;
2059 	    else if (dir == 'h')
2060 		new_size = fr->fr_height;
2061 	    else if (frame_fixed_height(fr))
2062 	    {
2063 		new_size = fr->fr_newheight;
2064 		wincount = 0;	    /* doesn't count as a sizeable window */
2065 	    }
2066 	    else
2067 	    {
2068 		/* Compute the maximum number of windows vert. in "fr". */
2069 		n = frame_minheight(fr, NOWIN);
2070 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2071 								/ (p_wmh + 1);
2072 		m = frame_minheight(fr, next_curwin);
2073 		if (has_next_curwin)
2074 		    hnc = frame_has_win(fr, next_curwin);
2075 		else
2076 		    hnc = FALSE;
2077 		if (hnc)	    /* don't count next_curwin */
2078 		    --wincount;
2079 		if (totwincount == 0)
2080 		    new_size = room;
2081 		else
2082 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2083 								/ totwincount;
2084 		if (hnc)	    /* add next_curwin size */
2085 		{
2086 		    next_curwin_size -= p_wh - (m - n);
2087 		    new_size += next_curwin_size;
2088 		    room -= new_size - next_curwin_size;
2089 		}
2090 		else
2091 		    room -= new_size;
2092 		new_size += n;
2093 	    }
2094 	    /* Skip frame that is full width when splitting or closing a
2095 	     * window, unless equalizing all frames. */
2096 	    if (!current || dir != 'h' || topfr->fr_parent != NULL
2097 		    || (new_size != fr->fr_height)
2098 		    || frame_has_win(fr, next_curwin))
2099 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2100 							     width, new_size);
2101 	    row += new_size;
2102 	    height -= new_size;
2103 	    totwincount -= wincount;
2104 	}
2105     }
2106 }
2107 
2108 #ifdef FEAT_JOB_CHANNEL
2109     static void
2110 leaving_window(win_T *win)
2111 {
2112     // Only matters for a prompt window.
2113     if (!bt_prompt(win->w_buffer))
2114 	return;
2115 
2116     // When leaving a prompt window stop Insert mode and perhaps restart
2117     // it when entering that window again.
2118     win->w_buffer->b_prompt_insert = restart_edit;
2119     if (restart_edit != 0 && mode_displayed)
2120 	clear_cmdline = TRUE;		/* unshow mode later */
2121     restart_edit = NUL;
2122 
2123     // When leaving the window (or closing the window) was done from a
2124     // callback we need to break out of the Insert mode loop and restart Insert
2125     // mode when entering the window again.
2126     if (State & INSERT)
2127     {
2128 	stop_insert_mode = TRUE;
2129 	if (win->w_buffer->b_prompt_insert == NUL)
2130 	    win->w_buffer->b_prompt_insert = 'A';
2131     }
2132 }
2133 
2134     static void
2135 entering_window(win_T *win)
2136 {
2137     // Only matters for a prompt window.
2138     if (!bt_prompt(win->w_buffer))
2139 	return;
2140 
2141     // When switching to a prompt buffer that was in Insert mode, don't stop
2142     // Insert mode, it may have been set in leaving_window().
2143     if (win->w_buffer->b_prompt_insert != NUL)
2144 	stop_insert_mode = FALSE;
2145 
2146     // When entering the prompt window restart Insert mode if we were in Insert
2147     // mode when we left it.
2148     restart_edit = win->w_buffer->b_prompt_insert;
2149 }
2150 #endif
2151 
2152 /*
2153  * Close all windows for buffer "buf".
2154  */
2155     void
2156 close_windows(
2157     buf_T	*buf,
2158     int		keep_curwin)	    /* don't close "curwin" */
2159 {
2160     win_T	*wp;
2161     tabpage_T   *tp, *nexttp;
2162     int		h = tabline_height();
2163     int		count = tabpage_index(NULL);
2164 
2165     ++RedrawingDisabled;
2166 
2167     for (wp = firstwin; wp != NULL && !ONE_WINDOW; )
2168     {
2169 	if (wp->w_buffer == buf && (!keep_curwin || wp != curwin)
2170 		&& !(wp->w_closing || wp->w_buffer->b_locked > 0))
2171 	{
2172 	    if (win_close(wp, FALSE) == FAIL)
2173 		/* If closing the window fails give up, to avoid looping
2174 		 * forever. */
2175 		break;
2176 
2177 	    /* Start all over, autocommands may change the window layout. */
2178 	    wp = firstwin;
2179 	}
2180 	else
2181 	    wp = wp->w_next;
2182     }
2183 
2184     /* Also check windows in other tab pages. */
2185     for (tp = first_tabpage; tp != NULL; tp = nexttp)
2186     {
2187 	nexttp = tp->tp_next;
2188 	if (tp != curtab)
2189 	    for (wp = tp->tp_firstwin; wp != NULL; wp = wp->w_next)
2190 		if (wp->w_buffer == buf
2191 		    && !(wp->w_closing || wp->w_buffer->b_locked > 0))
2192 		{
2193 		    win_close_othertab(wp, FALSE, tp);
2194 
2195 		    /* Start all over, the tab page may be closed and
2196 		     * autocommands may change the window layout. */
2197 		    nexttp = first_tabpage;
2198 		    break;
2199 		}
2200     }
2201 
2202     --RedrawingDisabled;
2203 
2204     if (count != tabpage_index(NULL))
2205 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2206 
2207     redraw_tabline = TRUE;
2208     if (h != tabline_height())
2209 	shell_new_rows();
2210 }
2211 
2212 /*
2213  * Return TRUE if the current window is the only window that exists (ignoring
2214  * "aucmd_win").
2215  * Returns FALSE if there is a window, possibly in another tab page.
2216  */
2217     static int
2218 last_window(void)
2219 {
2220     return (one_window() && first_tabpage->tp_next == NULL);
2221 }
2222 
2223 /*
2224  * Return TRUE if there is only one window other than "aucmd_win" in the
2225  * current tab page.
2226  */
2227     int
2228 one_window(void)
2229 {
2230     win_T	*wp;
2231     int		seen_one = FALSE;
2232 
2233     FOR_ALL_WINDOWS(wp)
2234     {
2235 	if (wp != aucmd_win)
2236 	{
2237 	    if (seen_one)
2238 		return FALSE;
2239 	    seen_one = TRUE;
2240 	}
2241     }
2242     return TRUE;
2243 }
2244 
2245 /*
2246  * Close the possibly last window in a tab page.
2247  * Returns TRUE when the window was closed already.
2248  */
2249     static int
2250 close_last_window_tabpage(
2251     win_T	*win,
2252     int		free_buf,
2253     tabpage_T   *prev_curtab)
2254 {
2255     if (ONE_WINDOW)
2256     {
2257 	buf_T	*old_curbuf = curbuf;
2258 
2259 	/*
2260 	 * Closing the last window in a tab page.  First go to another tab
2261 	 * page and then close the window and the tab page.  This avoids that
2262 	 * curwin and curtab are invalid while we are freeing memory, they may
2263 	 * be used in GUI events.
2264 	 * Don't trigger autocommands yet, they may use wrong values, so do
2265 	 * that below.
2266 	 */
2267 	goto_tabpage_tp(alt_tabpage(), FALSE, TRUE);
2268 	redraw_tabline = TRUE;
2269 
2270 	/* Safety check: Autocommands may have closed the window when jumping
2271 	 * to the other tab page. */
2272 	if (valid_tabpage(prev_curtab) && prev_curtab->tp_firstwin == win)
2273 	{
2274 	    int	    h = tabline_height();
2275 
2276 	    win_close_othertab(win, free_buf, prev_curtab);
2277 	    if (h != tabline_height())
2278 		shell_new_rows();
2279 	}
2280 #ifdef FEAT_JOB_CHANNEL
2281 	entering_window(curwin);
2282 #endif
2283 	/* Since goto_tabpage_tp above did not trigger *Enter autocommands, do
2284 	 * that now. */
2285 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2286 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
2287 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
2288 	if (old_curbuf != curbuf)
2289 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2290 	return TRUE;
2291     }
2292     return FALSE;
2293 }
2294 
2295 /*
2296  * Close window "win".  Only works for the current tab page.
2297  * If "free_buf" is TRUE related buffer may be unloaded.
2298  *
2299  * Called by :quit, :close, :xit, :wq and findtag().
2300  * Returns FAIL when the window was not closed.
2301  */
2302     int
2303 win_close(win_T *win, int free_buf)
2304 {
2305     win_T	*wp;
2306     int		other_buffer = FALSE;
2307     int		close_curwin = FALSE;
2308     int		dir;
2309     int		help_window = FALSE;
2310     tabpage_T   *prev_curtab = curtab;
2311     frame_T	*win_frame = win->w_frame->fr_parent;
2312 
2313     if (last_window())
2314     {
2315 	EMSG(_("E444: Cannot close last window"));
2316 	return FAIL;
2317     }
2318 
2319     if (win->w_closing || (win->w_buffer != NULL
2320 					       && win->w_buffer->b_locked > 0))
2321 	return FAIL; /* window is already being closed */
2322     if (win == aucmd_win)
2323     {
2324 	EMSG(_("E813: Cannot close autocmd window"));
2325 	return FAIL;
2326     }
2327     if ((firstwin == aucmd_win || lastwin == aucmd_win) && one_window())
2328     {
2329 	EMSG(_("E814: Cannot close window, only autocmd window would remain"));
2330 	return FAIL;
2331     }
2332 
2333     /* When closing the last window in a tab page first go to another tab page
2334      * and then close the window and the tab page to avoid that curwin and
2335      * curtab are invalid while we are freeing memory. */
2336     if (close_last_window_tabpage(win, free_buf, prev_curtab))
2337       return FAIL;
2338 
2339     /* When closing the help window, try restoring a snapshot after closing
2340      * the window.  Otherwise clear the snapshot, it's now invalid. */
2341     if (bt_help(win->w_buffer))
2342 	help_window = TRUE;
2343     else
2344 	clear_snapshot(curtab, SNAP_HELP_IDX);
2345 
2346     if (win == curwin)
2347     {
2348 #ifdef FEAT_JOB_CHANNEL
2349 	leaving_window(curwin);
2350 #endif
2351 	/*
2352 	 * Guess which window is going to be the new current window.
2353 	 * This may change because of the autocommands (sigh).
2354 	 */
2355 	wp = frame2win(win_altframe(win, NULL));
2356 
2357 	/*
2358 	 * Be careful: If autocommands delete the window or cause this window
2359 	 * to be the last one left, return now.
2360 	 */
2361 	if (wp->w_buffer != curbuf)
2362 	{
2363 	    other_buffer = TRUE;
2364 	    win->w_closing = TRUE;
2365 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
2366 	    if (!win_valid(win))
2367 		return FAIL;
2368 	    win->w_closing = FALSE;
2369 	    if (last_window())
2370 		return FAIL;
2371 	}
2372 	win->w_closing = TRUE;
2373 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
2374 	if (!win_valid(win))
2375 	    return FAIL;
2376 	win->w_closing = FALSE;
2377 	if (last_window())
2378 	    return FAIL;
2379 #ifdef FEAT_EVAL
2380 	/* autocmds may abort script processing */
2381 	if (aborting())
2382 	    return FAIL;
2383 #endif
2384     }
2385 
2386 #ifdef FEAT_GUI
2387     /* Avoid trouble with scrollbars that are going to be deleted in
2388      * win_free(). */
2389     if (gui.in_use)
2390 	out_flush();
2391 #endif
2392 
2393 #ifdef FEAT_SYN_HL
2394     /* Free independent synblock before the buffer is freed. */
2395     if (win->w_buffer != NULL)
2396 	reset_synblock(win);
2397 #endif
2398 
2399     /*
2400      * Close the link to the buffer.
2401      */
2402     if (win->w_buffer != NULL)
2403     {
2404 	bufref_T    bufref;
2405 
2406 	set_bufref(&bufref, curbuf);
2407 	win->w_closing = TRUE;
2408 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0, TRUE);
2409 	if (win_valid_any_tab(win))
2410 	    win->w_closing = FALSE;
2411 	/* Make sure curbuf is valid. It can become invalid if 'bufhidden' is
2412 	 * "wipe". */
2413 	if (!bufref_valid(&bufref))
2414 	    curbuf = firstbuf;
2415     }
2416 
2417     if (only_one_window() && win_valid(win) && win->w_buffer == NULL
2418 	    && (last_window() || curtab != prev_curtab
2419 		|| close_last_window_tabpage(win, free_buf, prev_curtab)))
2420     {
2421 	/* Autocommands have closed all windows, quit now.  Restore
2422 	 * curwin->w_buffer, otherwise writing viminfo may fail. */
2423 	if (curwin->w_buffer == NULL)
2424 	    curwin->w_buffer = curbuf;
2425 	getout(0);
2426     }
2427 
2428     /* Autocommands may have moved to another tab page. */
2429     if (curtab != prev_curtab && win_valid_any_tab(win)
2430 						      && win->w_buffer == NULL)
2431     {
2432 	/* Need to close the window anyway, since the buffer is NULL. */
2433 	win_close_othertab(win, FALSE, prev_curtab);
2434 	return FAIL;
2435     }
2436 
2437     /* Autocommands may have closed the window already or closed the only
2438      * other window. */
2439     if (!win_valid(win) || last_window()
2440 	    || close_last_window_tabpage(win, free_buf, prev_curtab))
2441 	return FAIL;
2442 
2443     /* Free the memory used for the window and get the window that received
2444      * the screen space. */
2445     wp = win_free_mem(win, &dir, NULL);
2446 
2447     /* Make sure curwin isn't invalid.  It can cause severe trouble when
2448      * printing an error message.  For win_equal() curbuf needs to be valid
2449      * too. */
2450     if (win == curwin)
2451     {
2452 	curwin = wp;
2453 #ifdef FEAT_QUICKFIX
2454 	if (wp->w_p_pvw || bt_quickfix(wp->w_buffer))
2455 	{
2456 	    /*
2457 	     * If the cursor goes to the preview or the quickfix window, try
2458 	     * finding another window to go to.
2459 	     */
2460 	    for (;;)
2461 	    {
2462 		if (wp->w_next == NULL)
2463 		    wp = firstwin;
2464 		else
2465 		    wp = wp->w_next;
2466 		if (wp == curwin)
2467 		    break;
2468 		if (!wp->w_p_pvw && !bt_quickfix(wp->w_buffer))
2469 		{
2470 		    curwin = wp;
2471 		    break;
2472 		}
2473 	    }
2474 	}
2475 #endif
2476 	curbuf = curwin->w_buffer;
2477 	close_curwin = TRUE;
2478 
2479 	/* The cursor position may be invalid if the buffer changed after last
2480 	 * using the window. */
2481 	check_cursor();
2482     }
2483     if (p_ea && (*p_ead == 'b' || *p_ead == dir))
2484 	/* If the frame of the closed window contains the new current window,
2485 	 * only resize that frame.  Otherwise resize all windows. */
2486 	win_equal(curwin, curwin->w_frame->fr_parent == win_frame, dir);
2487     else
2488 	win_comp_pos();
2489     if (close_curwin)
2490     {
2491 	win_enter_ext(wp, FALSE, TRUE, FALSE, TRUE, TRUE);
2492 	if (other_buffer)
2493 	    /* careful: after this wp and win may be invalid! */
2494 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2495     }
2496 
2497     /*
2498      * If last window has a status line now and we don't want one,
2499      * remove the status line.
2500      */
2501     last_status(FALSE);
2502 
2503     /* After closing the help window, try restoring the window layout from
2504      * before it was opened. */
2505     if (help_window)
2506 	restore_snapshot(SNAP_HELP_IDX, close_curwin);
2507 
2508 #if defined(FEAT_GUI)
2509     /* When 'guioptions' includes 'L' or 'R' may have to remove scrollbars. */
2510     if (gui.in_use && !win_hasvertsplit())
2511 	gui_init_which_components(NULL);
2512 #endif
2513 
2514     redraw_all_later(NOT_VALID);
2515     return OK;
2516 }
2517 
2518 /*
2519  * Close window "win" in tab page "tp", which is not the current tab page.
2520  * This may be the last window in that tab page and result in closing the tab,
2521  * thus "tp" may become invalid!
2522  * Caller must check if buffer is hidden and whether the tabline needs to be
2523  * updated.
2524  */
2525     void
2526 win_close_othertab(win_T *win, int free_buf, tabpage_T *tp)
2527 {
2528     win_T	*wp;
2529     int		dir;
2530     tabpage_T   *ptp = NULL;
2531     int		free_tp = FALSE;
2532 
2533     /* Get here with win->w_buffer == NULL when win_close() detects the tab
2534      * page changed. */
2535     if (win->w_closing || (win->w_buffer != NULL
2536 					       && win->w_buffer->b_locked > 0))
2537 	return; /* window is already being closed */
2538 
2539     if (win->w_buffer != NULL)
2540 	/* Close the link to the buffer. */
2541 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0, FALSE);
2542 
2543     /* Careful: Autocommands may have closed the tab page or made it the
2544      * current tab page.  */
2545     for (ptp = first_tabpage; ptp != NULL && ptp != tp; ptp = ptp->tp_next)
2546 	;
2547     if (ptp == NULL || tp == curtab)
2548 	return;
2549 
2550     /* Autocommands may have closed the window already. */
2551     for (wp = tp->tp_firstwin; wp != NULL && wp != win; wp = wp->w_next)
2552 	;
2553     if (wp == NULL)
2554 	return;
2555 
2556     /* When closing the last window in a tab page remove the tab page. */
2557     if (tp->tp_firstwin == tp->tp_lastwin)
2558     {
2559 	if (tp == first_tabpage)
2560 	    first_tabpage = tp->tp_next;
2561 	else
2562 	{
2563 	    for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tp;
2564 							   ptp = ptp->tp_next)
2565 		;
2566 	    if (ptp == NULL)
2567 	    {
2568 		internal_error("win_close_othertab()");
2569 		return;
2570 	    }
2571 	    ptp->tp_next = tp->tp_next;
2572 	}
2573 	free_tp = TRUE;
2574     }
2575 
2576     /* Free the memory used for the window. */
2577     win_free_mem(win, &dir, tp);
2578 
2579     if (free_tp)
2580 	free_tabpage(tp);
2581 }
2582 
2583 /*
2584  * Free the memory used for a window.
2585  * Returns a pointer to the window that got the freed up space.
2586  */
2587     static win_T *
2588 win_free_mem(
2589     win_T	*win,
2590     int		*dirp,		/* set to 'v' or 'h' for direction if 'ea' */
2591     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2592 {
2593     frame_T	*frp;
2594     win_T	*wp;
2595 
2596     /* Remove the window and its frame from the tree of frames. */
2597     frp = win->w_frame;
2598     wp = winframe_remove(win, dirp, tp);
2599     vim_free(frp);
2600     win_free(win, tp);
2601 
2602     /* When deleting the current window of another tab page select a new
2603      * current window. */
2604     if (tp != NULL && win == tp->tp_curwin)
2605 	tp->tp_curwin = wp;
2606 
2607     return wp;
2608 }
2609 
2610 #if defined(EXITFREE) || defined(PROTO)
2611     void
2612 win_free_all(void)
2613 {
2614     int		dummy;
2615 
2616     while (first_tabpage->tp_next != NULL)
2617 	tabpage_close(TRUE);
2618 
2619     if (aucmd_win != NULL)
2620     {
2621 	(void)win_free_mem(aucmd_win, &dummy, NULL);
2622 	aucmd_win = NULL;
2623     }
2624 
2625     while (firstwin != NULL)
2626 	(void)win_free_mem(firstwin, &dummy, NULL);
2627 
2628     /* No window should be used after this. Set curwin to NULL to crash
2629      * instead of using freed memory. */
2630     curwin = NULL;
2631 }
2632 #endif
2633 
2634 /*
2635  * Remove a window and its frame from the tree of frames.
2636  * Returns a pointer to the window that got the freed up space.
2637  */
2638     win_T *
2639 winframe_remove(
2640     win_T	*win,
2641     int		*dirp UNUSED,	/* set to 'v' or 'h' for direction if 'ea' */
2642     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2643 {
2644     frame_T	*frp, *frp2, *frp3;
2645     frame_T	*frp_close = win->w_frame;
2646     win_T	*wp;
2647 
2648     /*
2649      * If there is only one window there is nothing to remove.
2650      */
2651     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2652 	return NULL;
2653 
2654     /*
2655      * Remove the window from its frame.
2656      */
2657     frp2 = win_altframe(win, tp);
2658     wp = frame2win(frp2);
2659 
2660     /* Remove this frame from the list of frames. */
2661     frame_remove(frp_close);
2662 
2663     if (frp_close->fr_parent->fr_layout == FR_COL)
2664     {
2665 	/* When 'winfixheight' is set, try to find another frame in the column
2666 	 * (as close to the closed frame as possible) to distribute the height
2667 	 * to. */
2668 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfh)
2669 	{
2670 	    frp = frp_close->fr_prev;
2671 	    frp3 = frp_close->fr_next;
2672 	    while (frp != NULL || frp3 != NULL)
2673 	    {
2674 		if (frp != NULL)
2675 		{
2676 		    if (frp->fr_win != NULL && !frp->fr_win->w_p_wfh)
2677 		    {
2678 			frp2 = frp;
2679 			wp = frp->fr_win;
2680 			break;
2681 		    }
2682 		    frp = frp->fr_prev;
2683 		}
2684 		if (frp3 != NULL)
2685 		{
2686 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfh)
2687 		    {
2688 			frp2 = frp3;
2689 			wp = frp3->fr_win;
2690 			break;
2691 		    }
2692 		    frp3 = frp3->fr_next;
2693 		}
2694 	    }
2695 	}
2696 	frame_new_height(frp2, frp2->fr_height + frp_close->fr_height,
2697 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2698 	*dirp = 'v';
2699     }
2700     else
2701     {
2702 	/* When 'winfixwidth' is set, try to find another frame in the column
2703 	 * (as close to the closed frame as possible) to distribute the width
2704 	 * to. */
2705 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfw)
2706 	{
2707 	    frp = frp_close->fr_prev;
2708 	    frp3 = frp_close->fr_next;
2709 	    while (frp != NULL || frp3 != NULL)
2710 	    {
2711 		if (frp != NULL)
2712 		{
2713 		    if (frp->fr_win != NULL && !frp->fr_win->w_p_wfw)
2714 		    {
2715 			frp2 = frp;
2716 			wp = frp->fr_win;
2717 			break;
2718 		    }
2719 		    frp = frp->fr_prev;
2720 		}
2721 		if (frp3 != NULL)
2722 		{
2723 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfw)
2724 		    {
2725 			frp2 = frp3;
2726 			wp = frp3->fr_win;
2727 			break;
2728 		    }
2729 		    frp3 = frp3->fr_next;
2730 		}
2731 	    }
2732 	}
2733 	frame_new_width(frp2, frp2->fr_width + frp_close->fr_width,
2734 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2735 	*dirp = 'h';
2736     }
2737 
2738     /* If rows/columns go to a window below/right its positions need to be
2739      * updated.  Can only be done after the sizes have been updated. */
2740     if (frp2 == frp_close->fr_next)
2741     {
2742 	int row = win->w_winrow;
2743 	int col = win->w_wincol;
2744 
2745 	frame_comp_pos(frp2, &row, &col);
2746     }
2747 
2748     if (frp2->fr_next == NULL && frp2->fr_prev == NULL)
2749     {
2750 	/* There is no other frame in this list, move its info to the parent
2751 	 * and remove it. */
2752 	frp2->fr_parent->fr_layout = frp2->fr_layout;
2753 	frp2->fr_parent->fr_child = frp2->fr_child;
2754 	for (frp = frp2->fr_child; frp != NULL; frp = frp->fr_next)
2755 	    frp->fr_parent = frp2->fr_parent;
2756 	frp2->fr_parent->fr_win = frp2->fr_win;
2757 	if (frp2->fr_win != NULL)
2758 	    frp2->fr_win->w_frame = frp2->fr_parent;
2759 	frp = frp2->fr_parent;
2760 	if (topframe->fr_child == frp2)
2761 	    topframe->fr_child = frp;
2762 	vim_free(frp2);
2763 
2764 	frp2 = frp->fr_parent;
2765 	if (frp2 != NULL && frp2->fr_layout == frp->fr_layout)
2766 	{
2767 	    /* The frame above the parent has the same layout, have to merge
2768 	     * the frames into this list. */
2769 	    if (frp2->fr_child == frp)
2770 		frp2->fr_child = frp->fr_child;
2771 	    frp->fr_child->fr_prev = frp->fr_prev;
2772 	    if (frp->fr_prev != NULL)
2773 		frp->fr_prev->fr_next = frp->fr_child;
2774 	    for (frp3 = frp->fr_child; ; frp3 = frp3->fr_next)
2775 	    {
2776 		frp3->fr_parent = frp2;
2777 		if (frp3->fr_next == NULL)
2778 		{
2779 		    frp3->fr_next = frp->fr_next;
2780 		    if (frp->fr_next != NULL)
2781 			frp->fr_next->fr_prev = frp3;
2782 		    break;
2783 		}
2784 	    }
2785 	    if (topframe->fr_child == frp)
2786 		topframe->fr_child = frp2;
2787 	    vim_free(frp);
2788 	}
2789     }
2790 
2791     return wp;
2792 }
2793 
2794 /*
2795  * Return a pointer to the frame that will receive the empty screen space that
2796  * is left over after "win" is closed.
2797  *
2798  * If 'splitbelow' or 'splitright' is set, the space goes above or to the left
2799  * by default.  Otherwise, the free space goes below or to the right.  The
2800  * result is that opening a window and then immediately closing it will
2801  * preserve the initial window layout.  The 'wfh' and 'wfw' settings are
2802  * respected when possible.
2803  */
2804     static frame_T *
2805 win_altframe(
2806     win_T	*win,
2807     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2808 {
2809     frame_T	*frp;
2810     frame_T	*other_fr, *target_fr;
2811 
2812     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2813 	return alt_tabpage()->tp_curwin->w_frame;
2814 
2815     frp = win->w_frame;
2816 
2817     if (frp->fr_prev == NULL)
2818 	return frp->fr_next;
2819     if (frp->fr_next == NULL)
2820 	return frp->fr_prev;
2821 
2822     target_fr = frp->fr_next;
2823     other_fr  = frp->fr_prev;
2824     if (p_spr || p_sb)
2825     {
2826 	target_fr = frp->fr_prev;
2827 	other_fr  = frp->fr_next;
2828     }
2829 
2830     /* If 'wfh' or 'wfw' is set for the target and not for the alternate
2831      * window, reverse the selection. */
2832     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW)
2833     {
2834 	if (frame_fixed_width(target_fr) && !frame_fixed_width(other_fr))
2835 	    target_fr = other_fr;
2836     }
2837     else
2838     {
2839 	if (frame_fixed_height(target_fr) && !frame_fixed_height(other_fr))
2840 	    target_fr = other_fr;
2841     }
2842 
2843     return target_fr;
2844 }
2845 
2846 /*
2847  * Return the tabpage that will be used if the current one is closed.
2848  */
2849     static tabpage_T *
2850 alt_tabpage(void)
2851 {
2852     tabpage_T	*tp;
2853 
2854     /* Use the next tab page if possible. */
2855     if (curtab->tp_next != NULL)
2856 	return curtab->tp_next;
2857 
2858     /* Find the last but one tab page. */
2859     for (tp = first_tabpage; tp->tp_next != curtab; tp = tp->tp_next)
2860 	;
2861     return tp;
2862 }
2863 
2864 /*
2865  * Find the left-upper window in frame "frp".
2866  */
2867     static win_T *
2868 frame2win(frame_T *frp)
2869 {
2870     while (frp->fr_win == NULL)
2871 	frp = frp->fr_child;
2872     return frp->fr_win;
2873 }
2874 
2875 /*
2876  * Return TRUE if frame "frp" contains window "wp".
2877  */
2878     static int
2879 frame_has_win(frame_T *frp, win_T *wp)
2880 {
2881     frame_T	*p;
2882 
2883     if (frp->fr_layout == FR_LEAF)
2884 	return frp->fr_win == wp;
2885 
2886     for (p = frp->fr_child; p != NULL; p = p->fr_next)
2887 	if (frame_has_win(p, wp))
2888 	    return TRUE;
2889     return FALSE;
2890 }
2891 
2892 /*
2893  * Set a new height for a frame.  Recursively sets the height for contained
2894  * frames and windows.  Caller must take care of positions.
2895  */
2896     static void
2897 frame_new_height(
2898     frame_T	*topfrp,
2899     int		height,
2900     int		topfirst,	/* resize topmost contained frame first */
2901     int		wfh)		/* obey 'winfixheight' when there is a choice;
2902 				   may cause the height not to be set */
2903 {
2904     frame_T	*frp;
2905     int		extra_lines;
2906     int		h;
2907 
2908     if (topfrp->fr_win != NULL)
2909     {
2910 	/* Simple case: just one window. */
2911 	win_new_height(topfrp->fr_win,
2912 				    height - topfrp->fr_win->w_status_height
2913 					      - WINBAR_HEIGHT(topfrp->fr_win));
2914     }
2915     else if (topfrp->fr_layout == FR_ROW)
2916     {
2917 	do
2918 	{
2919 	    /* All frames in this row get the same new height. */
2920 	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
2921 	    {
2922 		frame_new_height(frp, height, topfirst, wfh);
2923 		if (frp->fr_height > height)
2924 		{
2925 		    /* Could not fit the windows, make the whole row higher. */
2926 		    height = frp->fr_height;
2927 		    break;
2928 		}
2929 	    }
2930 	}
2931 	while (frp != NULL);
2932     }
2933     else    /* fr_layout == FR_COL */
2934     {
2935 	/* Complicated case: Resize a column of frames.  Resize the bottom
2936 	 * frame first, frames above that when needed. */
2937 
2938 	frp = topfrp->fr_child;
2939 	if (wfh)
2940 	    /* Advance past frames with one window with 'wfh' set. */
2941 	    while (frame_fixed_height(frp))
2942 	    {
2943 		frp = frp->fr_next;
2944 		if (frp == NULL)
2945 		    return;	    /* no frame without 'wfh', give up */
2946 	    }
2947 	if (!topfirst)
2948 	{
2949 	    /* Find the bottom frame of this column */
2950 	    while (frp->fr_next != NULL)
2951 		frp = frp->fr_next;
2952 	    if (wfh)
2953 		/* Advance back for frames with one window with 'wfh' set. */
2954 		while (frame_fixed_height(frp))
2955 		    frp = frp->fr_prev;
2956 	}
2957 
2958 	extra_lines = height - topfrp->fr_height;
2959 	if (extra_lines < 0)
2960 	{
2961 	    /* reduce height of contained frames, bottom or top frame first */
2962 	    while (frp != NULL)
2963 	    {
2964 		h = frame_minheight(frp, NULL);
2965 		if (frp->fr_height + extra_lines < h)
2966 		{
2967 		    extra_lines += frp->fr_height - h;
2968 		    frame_new_height(frp, h, topfirst, wfh);
2969 		}
2970 		else
2971 		{
2972 		    frame_new_height(frp, frp->fr_height + extra_lines,
2973 							       topfirst, wfh);
2974 		    break;
2975 		}
2976 		if (topfirst)
2977 		{
2978 		    do
2979 			frp = frp->fr_next;
2980 		    while (wfh && frp != NULL && frame_fixed_height(frp));
2981 		}
2982 		else
2983 		{
2984 		    do
2985 			frp = frp->fr_prev;
2986 		    while (wfh && frp != NULL && frame_fixed_height(frp));
2987 		}
2988 		/* Increase "height" if we could not reduce enough frames. */
2989 		if (frp == NULL)
2990 		    height -= extra_lines;
2991 	    }
2992 	}
2993 	else if (extra_lines > 0)
2994 	{
2995 	    /* increase height of bottom or top frame */
2996 	    frame_new_height(frp, frp->fr_height + extra_lines, topfirst, wfh);
2997 	}
2998     }
2999     topfrp->fr_height = height;
3000 }
3001 
3002 /*
3003  * Return TRUE if height of frame "frp" should not be changed because of
3004  * the 'winfixheight' option.
3005  */
3006     static int
3007 frame_fixed_height(frame_T *frp)
3008 {
3009     /* frame with one window: fixed height if 'winfixheight' set. */
3010     if (frp->fr_win != NULL)
3011 	return frp->fr_win->w_p_wfh;
3012 
3013     if (frp->fr_layout == FR_ROW)
3014     {
3015 	/* The frame is fixed height if one of the frames in the row is fixed
3016 	 * height. */
3017 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3018 	    if (frame_fixed_height(frp))
3019 		return TRUE;
3020 	return FALSE;
3021     }
3022 
3023     /* frp->fr_layout == FR_COL: The frame is fixed height if all of the
3024      * frames in the row are fixed height. */
3025     for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3026 	if (!frame_fixed_height(frp))
3027 	    return FALSE;
3028     return TRUE;
3029 }
3030 
3031 /*
3032  * Return TRUE if width of frame "frp" should not be changed because of
3033  * the 'winfixwidth' option.
3034  */
3035     static int
3036 frame_fixed_width(frame_T *frp)
3037 {
3038     /* frame with one window: fixed width if 'winfixwidth' set. */
3039     if (frp->fr_win != NULL)
3040 	return frp->fr_win->w_p_wfw;
3041 
3042     if (frp->fr_layout == FR_COL)
3043     {
3044 	/* The frame is fixed width if one of the frames in the row is fixed
3045 	 * width. */
3046 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3047 	    if (frame_fixed_width(frp))
3048 		return TRUE;
3049 	return FALSE;
3050     }
3051 
3052     /* frp->fr_layout == FR_ROW: The frame is fixed width if all of the
3053      * frames in the row are fixed width. */
3054     for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3055 	if (!frame_fixed_width(frp))
3056 	    return FALSE;
3057     return TRUE;
3058 }
3059 
3060 /*
3061  * Add a status line to windows at the bottom of "frp".
3062  * Note: Does not check if there is room!
3063  */
3064     static void
3065 frame_add_statusline(frame_T *frp)
3066 {
3067     win_T	*wp;
3068 
3069     if (frp->fr_layout == FR_LEAF)
3070     {
3071 	wp = frp->fr_win;
3072 	if (wp->w_status_height == 0)
3073 	{
3074 	    if (wp->w_height > 0)	/* don't make it negative */
3075 		--wp->w_height;
3076 	    wp->w_status_height = STATUS_HEIGHT;
3077 	}
3078     }
3079     else if (frp->fr_layout == FR_ROW)
3080     {
3081 	/* Handle all the frames in the row. */
3082 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3083 	    frame_add_statusline(frp);
3084     }
3085     else /* frp->fr_layout == FR_COL */
3086     {
3087 	/* Only need to handle the last frame in the column. */
3088 	for (frp = frp->fr_child; frp->fr_next != NULL; frp = frp->fr_next)
3089 	    ;
3090 	frame_add_statusline(frp);
3091     }
3092 }
3093 
3094 /*
3095  * Set width of a frame.  Handles recursively going through contained frames.
3096  * May remove separator line for windows at the right side (for win_close()).
3097  */
3098     static void
3099 frame_new_width(
3100     frame_T	*topfrp,
3101     int		width,
3102     int		leftfirst,	/* resize leftmost contained frame first */
3103     int		wfw)		/* obey 'winfixwidth' when there is a choice;
3104 				   may cause the width not to be set */
3105 {
3106     frame_T	*frp;
3107     int		extra_cols;
3108     int		w;
3109     win_T	*wp;
3110 
3111     if (topfrp->fr_layout == FR_LEAF)
3112     {
3113 	/* Simple case: just one window. */
3114 	wp = topfrp->fr_win;
3115 	/* Find out if there are any windows right of this one. */
3116 	for (frp = topfrp; frp->fr_parent != NULL; frp = frp->fr_parent)
3117 	    if (frp->fr_parent->fr_layout == FR_ROW && frp->fr_next != NULL)
3118 		break;
3119 	if (frp->fr_parent == NULL)
3120 	    wp->w_vsep_width = 0;
3121 	win_new_width(wp, width - wp->w_vsep_width);
3122     }
3123     else if (topfrp->fr_layout == FR_COL)
3124     {
3125 	do
3126 	{
3127 	    /* All frames in this column get the same new width. */
3128 	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3129 	    {
3130 		frame_new_width(frp, width, leftfirst, wfw);
3131 		if (frp->fr_width > width)
3132 		{
3133 		    /* Could not fit the windows, make whole column wider. */
3134 		    width = frp->fr_width;
3135 		    break;
3136 		}
3137 	    }
3138 	} while (frp != NULL);
3139     }
3140     else    /* fr_layout == FR_ROW */
3141     {
3142 	/* Complicated case: Resize a row of frames.  Resize the rightmost
3143 	 * frame first, frames left of it when needed. */
3144 
3145 	frp = topfrp->fr_child;
3146 	if (wfw)
3147 	    /* Advance past frames with one window with 'wfw' set. */
3148 	    while (frame_fixed_width(frp))
3149 	    {
3150 		frp = frp->fr_next;
3151 		if (frp == NULL)
3152 		    return;	    /* no frame without 'wfw', give up */
3153 	    }
3154 	if (!leftfirst)
3155 	{
3156 	    /* Find the rightmost frame of this row */
3157 	    while (frp->fr_next != NULL)
3158 		frp = frp->fr_next;
3159 	    if (wfw)
3160 		/* Advance back for frames with one window with 'wfw' set. */
3161 		while (frame_fixed_width(frp))
3162 		    frp = frp->fr_prev;
3163 	}
3164 
3165 	extra_cols = width - topfrp->fr_width;
3166 	if (extra_cols < 0)
3167 	{
3168 	    /* reduce frame width, rightmost frame first */
3169 	    while (frp != NULL)
3170 	    {
3171 		w = frame_minwidth(frp, NULL);
3172 		if (frp->fr_width + extra_cols < w)
3173 		{
3174 		    extra_cols += frp->fr_width - w;
3175 		    frame_new_width(frp, w, leftfirst, wfw);
3176 		}
3177 		else
3178 		{
3179 		    frame_new_width(frp, frp->fr_width + extra_cols,
3180 							      leftfirst, wfw);
3181 		    break;
3182 		}
3183 		if (leftfirst)
3184 		{
3185 		    do
3186 			frp = frp->fr_next;
3187 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3188 		}
3189 		else
3190 		{
3191 		    do
3192 			frp = frp->fr_prev;
3193 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3194 		}
3195 		/* Increase "width" if we could not reduce enough frames. */
3196 		if (frp == NULL)
3197 		    width -= extra_cols;
3198 	    }
3199 	}
3200 	else if (extra_cols > 0)
3201 	{
3202 	    /* increase width of rightmost frame */
3203 	    frame_new_width(frp, frp->fr_width + extra_cols, leftfirst, wfw);
3204 	}
3205     }
3206     topfrp->fr_width = width;
3207 }
3208 
3209 /*
3210  * Add the vertical separator to windows at the right side of "frp".
3211  * Note: Does not check if there is room!
3212  */
3213     static void
3214 frame_add_vsep(frame_T *frp)
3215 {
3216     win_T	*wp;
3217 
3218     if (frp->fr_layout == FR_LEAF)
3219     {
3220 	wp = frp->fr_win;
3221 	if (wp->w_vsep_width == 0)
3222 	{
3223 	    if (wp->w_width > 0)	/* don't make it negative */
3224 		--wp->w_width;
3225 	    wp->w_vsep_width = 1;
3226 	}
3227     }
3228     else if (frp->fr_layout == FR_COL)
3229     {
3230 	/* Handle all the frames in the column. */
3231 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3232 	    frame_add_vsep(frp);
3233     }
3234     else /* frp->fr_layout == FR_ROW */
3235     {
3236 	/* Only need to handle the last frame in the row. */
3237 	frp = frp->fr_child;
3238 	while (frp->fr_next != NULL)
3239 	    frp = frp->fr_next;
3240 	frame_add_vsep(frp);
3241     }
3242 }
3243 
3244 /*
3245  * Set frame width from the window it contains.
3246  */
3247     static void
3248 frame_fix_width(win_T *wp)
3249 {
3250     wp->w_frame->fr_width = wp->w_width + wp->w_vsep_width;
3251 }
3252 
3253 /*
3254  * Set frame height from the window it contains.
3255  */
3256     static void
3257 frame_fix_height(win_T *wp)
3258 {
3259     wp->w_frame->fr_height = VISIBLE_HEIGHT(wp) + wp->w_status_height;
3260 }
3261 
3262 /*
3263  * Compute the minimal height for frame "topfrp".
3264  * Uses the 'winminheight' option.
3265  * When "next_curwin" isn't NULL, use p_wh for this window.
3266  * When "next_curwin" is NOWIN, don't use at least one line for the current
3267  * window.
3268  */
3269     static int
3270 frame_minheight(frame_T *topfrp, win_T *next_curwin)
3271 {
3272     frame_T	*frp;
3273     int		m;
3274     int		n;
3275 
3276     if (topfrp->fr_win != NULL)
3277     {
3278 	if (topfrp->fr_win == next_curwin)
3279 	    m = p_wh + topfrp->fr_win->w_status_height;
3280 	else
3281 	{
3282 	    /* window: minimal height of the window plus status line */
3283 	    m = p_wmh + topfrp->fr_win->w_status_height;
3284 	    if (topfrp->fr_win == curwin && next_curwin == NULL)
3285 	    {
3286 		/* Current window is minimal one line high and WinBar is
3287 		 * visible. */
3288 		if (p_wmh == 0)
3289 		    ++m;
3290 		m += WINBAR_HEIGHT(curwin);
3291 	    }
3292 	}
3293     }
3294     else if (topfrp->fr_layout == FR_ROW)
3295     {
3296 	/* get the minimal height from each frame in this row */
3297 	m = 0;
3298 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3299 	{
3300 	    n = frame_minheight(frp, next_curwin);
3301 	    if (n > m)
3302 		m = n;
3303 	}
3304     }
3305     else
3306     {
3307 	/* Add up the minimal heights for all frames in this column. */
3308 	m = 0;
3309 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3310 	    m += frame_minheight(frp, next_curwin);
3311     }
3312 
3313     return m;
3314 }
3315 
3316 /*
3317  * Compute the minimal width for frame "topfrp".
3318  * When "next_curwin" isn't NULL, use p_wiw for this window.
3319  * When "next_curwin" is NOWIN, don't use at least one column for the current
3320  * window.
3321  */
3322     static int
3323 frame_minwidth(
3324     frame_T	*topfrp,
3325     win_T	*next_curwin)	/* use p_wh and p_wiw for next_curwin */
3326 {
3327     frame_T	*frp;
3328     int		m, n;
3329 
3330     if (topfrp->fr_win != NULL)
3331     {
3332 	if (topfrp->fr_win == next_curwin)
3333 	    m = p_wiw + topfrp->fr_win->w_vsep_width;
3334 	else
3335 	{
3336 	    /* window: minimal width of the window plus separator column */
3337 	    m = p_wmw + topfrp->fr_win->w_vsep_width;
3338 	    /* Current window is minimal one column wide */
3339 	    if (p_wmw == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3340 		++m;
3341 	}
3342     }
3343     else if (topfrp->fr_layout == FR_COL)
3344     {
3345 	/* get the minimal width from each frame in this column */
3346 	m = 0;
3347 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3348 	{
3349 	    n = frame_minwidth(frp, next_curwin);
3350 	    if (n > m)
3351 		m = n;
3352 	}
3353     }
3354     else
3355     {
3356 	/* Add up the minimal widths for all frames in this row. */
3357 	m = 0;
3358 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3359 	    m += frame_minwidth(frp, next_curwin);
3360     }
3361 
3362     return m;
3363 }
3364 
3365 
3366 /*
3367  * Try to close all windows except current one.
3368  * Buffers in the other windows become hidden if 'hidden' is set, or '!' is
3369  * used and the buffer was modified.
3370  *
3371  * Used by ":bdel" and ":only".
3372  */
3373     void
3374 close_others(
3375     int		message,
3376     int		forceit)	    /* always hide all other windows */
3377 {
3378     win_T	*wp;
3379     win_T	*nextwp;
3380     int		r;
3381 
3382     if (one_window())
3383     {
3384 	if (message && !autocmd_busy)
3385 	    MSG(_(m_onlyone));
3386 	return;
3387     }
3388 
3389     /* Be very careful here: autocommands may change the window layout. */
3390     for (wp = firstwin; win_valid(wp); wp = nextwp)
3391     {
3392 	nextwp = wp->w_next;
3393 	if (wp != curwin)		/* don't close current window */
3394 	{
3395 
3396 	    /* Check if it's allowed to abandon this window */
3397 	    r = can_abandon(wp->w_buffer, forceit);
3398 	    if (!win_valid(wp))		/* autocommands messed wp up */
3399 	    {
3400 		nextwp = firstwin;
3401 		continue;
3402 	    }
3403 	    if (!r)
3404 	    {
3405 #if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
3406 		if (message && (p_confirm || cmdmod.confirm) && p_write)
3407 		{
3408 		    dialog_changed(wp->w_buffer, FALSE);
3409 		    if (!win_valid(wp))		/* autocommands messed wp up */
3410 		    {
3411 			nextwp = firstwin;
3412 			continue;
3413 		    }
3414 		}
3415 		if (bufIsChanged(wp->w_buffer))
3416 #endif
3417 		    continue;
3418 	    }
3419 	    win_close(wp, !buf_hide(wp->w_buffer)
3420 					       && !bufIsChanged(wp->w_buffer));
3421 	}
3422     }
3423 
3424     if (message && !ONE_WINDOW)
3425 	EMSG(_("E445: Other window contains changes"));
3426 }
3427 
3428 /*
3429  * Init the current window "curwin".
3430  * Called when a new file is being edited.
3431  */
3432     void
3433 curwin_init(void)
3434 {
3435     win_init_empty(curwin);
3436 }
3437 
3438     void
3439 win_init_empty(win_T *wp)
3440 {
3441     redraw_win_later(wp, NOT_VALID);
3442     wp->w_lines_valid = 0;
3443     wp->w_cursor.lnum = 1;
3444     wp->w_curswant = wp->w_cursor.col = 0;
3445 #ifdef FEAT_VIRTUALEDIT
3446     wp->w_cursor.coladd = 0;
3447 #endif
3448     wp->w_pcmark.lnum = 1;	/* pcmark not cleared but set to line 1 */
3449     wp->w_pcmark.col = 0;
3450     wp->w_prev_pcmark.lnum = 0;
3451     wp->w_prev_pcmark.col = 0;
3452     wp->w_topline = 1;
3453 #ifdef FEAT_DIFF
3454     wp->w_topfill = 0;
3455 #endif
3456     wp->w_botline = 2;
3457 #ifdef FEAT_FKMAP
3458     if (wp->w_p_rl)
3459 	wp->w_farsi = W_CONV + W_R_L;
3460     else
3461 	wp->w_farsi = W_CONV;
3462 #endif
3463 #ifdef FEAT_SYN_HL
3464     wp->w_s = &wp->w_buffer->b_s;
3465 #endif
3466 }
3467 
3468 /*
3469  * Allocate the first window and put an empty buffer in it.
3470  * Called from main().
3471  * Return FAIL when something goes wrong (out of memory).
3472  */
3473     int
3474 win_alloc_first(void)
3475 {
3476     if (win_alloc_firstwin(NULL) == FAIL)
3477 	return FAIL;
3478 
3479     first_tabpage = alloc_tabpage();
3480     if (first_tabpage == NULL)
3481 	return FAIL;
3482     first_tabpage->tp_topframe = topframe;
3483     curtab = first_tabpage;
3484 
3485     return OK;
3486 }
3487 
3488 /*
3489  * Init "aucmd_win".  This can only be done after the first
3490  * window is fully initialized, thus it can't be in win_alloc_first().
3491  */
3492     void
3493 win_alloc_aucmd_win(void)
3494 {
3495     aucmd_win = win_alloc(NULL, TRUE);
3496     if (aucmd_win != NULL)
3497     {
3498 	win_init_some(aucmd_win, curwin);
3499 	RESET_BINDING(aucmd_win);
3500 	new_frame(aucmd_win);
3501     }
3502 }
3503 
3504 /*
3505  * Allocate the first window or the first window in a new tab page.
3506  * When "oldwin" is NULL create an empty buffer for it.
3507  * When "oldwin" is not NULL copy info from it to the new window.
3508  * Return FAIL when something goes wrong (out of memory).
3509  */
3510     static int
3511 win_alloc_firstwin(win_T *oldwin)
3512 {
3513     curwin = win_alloc(NULL, FALSE);
3514     if (oldwin == NULL)
3515     {
3516 	/* Very first window, need to create an empty buffer for it and
3517 	 * initialize from scratch. */
3518 	curbuf = buflist_new(NULL, NULL, 1L, BLN_LISTED);
3519 	if (curwin == NULL || curbuf == NULL)
3520 	    return FAIL;
3521 	curwin->w_buffer = curbuf;
3522 #ifdef FEAT_SYN_HL
3523 	curwin->w_s = &(curbuf->b_s);
3524 #endif
3525 	curbuf->b_nwindows = 1;	/* there is one window */
3526 	curwin->w_alist = &global_alist;
3527 	curwin_init();		/* init current window */
3528     }
3529     else
3530     {
3531 	/* First window in new tab page, initialize it from "oldwin". */
3532 	win_init(curwin, oldwin, 0);
3533 
3534 	/* We don't want cursor- and scroll-binding in the first window. */
3535 	RESET_BINDING(curwin);
3536     }
3537 
3538     new_frame(curwin);
3539     if (curwin->w_frame == NULL)
3540 	return FAIL;
3541     topframe = curwin->w_frame;
3542     topframe->fr_width = Columns;
3543     topframe->fr_height = Rows - p_ch;
3544 
3545     return OK;
3546 }
3547 
3548 /*
3549  * Create a frame for window "wp".
3550  */
3551     static void
3552 new_frame(win_T *wp)
3553 {
3554     frame_T *frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
3555 
3556     wp->w_frame = frp;
3557     if (frp != NULL)
3558     {
3559 	frp->fr_layout = FR_LEAF;
3560 	frp->fr_win = wp;
3561     }
3562 }
3563 
3564 /*
3565  * Initialize the window and frame size to the maximum.
3566  */
3567     void
3568 win_init_size(void)
3569 {
3570     firstwin->w_height = ROWS_AVAIL;
3571     topframe->fr_height = ROWS_AVAIL;
3572     firstwin->w_width = Columns;
3573     topframe->fr_width = Columns;
3574 }
3575 
3576 /*
3577  * Allocate a new tabpage_T and init the values.
3578  * Returns NULL when out of memory.
3579  */
3580     static tabpage_T *
3581 alloc_tabpage(void)
3582 {
3583     tabpage_T	*tp;
3584 # ifdef FEAT_GUI
3585     int		i;
3586 # endif
3587 
3588 
3589     tp = (tabpage_T *)alloc_clear((unsigned)sizeof(tabpage_T));
3590     if (tp == NULL)
3591 	return NULL;
3592 
3593 # ifdef FEAT_EVAL
3594     /* init t: variables */
3595     tp->tp_vars = dict_alloc();
3596     if (tp->tp_vars == NULL)
3597     {
3598 	vim_free(tp);
3599 	return NULL;
3600     }
3601     init_var_dict(tp->tp_vars, &tp->tp_winvar, VAR_SCOPE);
3602 # endif
3603 
3604 # ifdef FEAT_GUI
3605     for (i = 0; i < 3; i++)
3606 	tp->tp_prev_which_scrollbars[i] = -1;
3607 # endif
3608 # ifdef FEAT_DIFF
3609     tp->tp_diff_invalid = TRUE;
3610 # endif
3611     tp->tp_ch_used = p_ch;
3612 
3613     return tp;
3614 }
3615 
3616     void
3617 free_tabpage(tabpage_T *tp)
3618 {
3619     int idx;
3620 
3621 # ifdef FEAT_DIFF
3622     diff_clear(tp);
3623 # endif
3624     for (idx = 0; idx < SNAP_COUNT; ++idx)
3625 	clear_snapshot(tp, idx);
3626 #ifdef FEAT_EVAL
3627     vars_clear(&tp->tp_vars->dv_hashtab);	/* free all t: variables */
3628     hash_init(&tp->tp_vars->dv_hashtab);
3629     unref_var_dict(tp->tp_vars);
3630 #endif
3631 
3632 #ifdef FEAT_PYTHON
3633     python_tabpage_free(tp);
3634 #endif
3635 
3636 #ifdef FEAT_PYTHON3
3637     python3_tabpage_free(tp);
3638 #endif
3639 
3640     vim_free(tp);
3641 }
3642 
3643 /*
3644  * Create a new Tab page with one window.
3645  * It will edit the current buffer, like after ":split".
3646  * When "after" is 0 put it just after the current Tab page.
3647  * Otherwise put it just before tab page "after".
3648  * Return FAIL or OK.
3649  */
3650     int
3651 win_new_tabpage(int after)
3652 {
3653     tabpage_T	*tp = curtab;
3654     tabpage_T	*newtp;
3655     int		n;
3656 
3657     newtp = alloc_tabpage();
3658     if (newtp == NULL)
3659 	return FAIL;
3660 
3661     /* Remember the current windows in this Tab page. */
3662     if (leave_tabpage(curbuf, TRUE) == FAIL)
3663     {
3664 	vim_free(newtp);
3665 	return FAIL;
3666     }
3667     curtab = newtp;
3668 
3669     /* Create a new empty window. */
3670     if (win_alloc_firstwin(tp->tp_curwin) == OK)
3671     {
3672 	/* Make the new Tab page the new topframe. */
3673 	if (after == 1)
3674 	{
3675 	    /* New tab page becomes the first one. */
3676 	    newtp->tp_next = first_tabpage;
3677 	    first_tabpage = newtp;
3678 	}
3679 	else
3680 	{
3681 	    if (after > 0)
3682 	    {
3683 		/* Put new tab page before tab page "after". */
3684 		n = 2;
3685 		for (tp = first_tabpage; tp->tp_next != NULL
3686 					       && n < after; tp = tp->tp_next)
3687 		    ++n;
3688 	    }
3689 	    newtp->tp_next = tp->tp_next;
3690 	    tp->tp_next = newtp;
3691 	}
3692 	win_init_size();
3693 	firstwin->w_winrow = tabline_height();
3694 	win_comp_scroll(curwin);
3695 
3696 	newtp->tp_topframe = topframe;
3697 	last_status(FALSE);
3698 
3699 #if defined(FEAT_GUI)
3700 	/* When 'guioptions' includes 'L' or 'R' may have to remove or add
3701 	 * scrollbars.  Have to update them anyway. */
3702 	gui_may_update_scrollbars();
3703 #endif
3704 #ifdef FEAT_JOB_CHANNEL
3705 	entering_window(curwin);
3706 #endif
3707 
3708 	redraw_all_later(CLEAR);
3709 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
3710 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
3711 	apply_autocmds(EVENT_TABNEW, NULL, NULL, FALSE, curbuf);
3712 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3713 	return OK;
3714     }
3715 
3716     /* Failed, get back the previous Tab page */
3717     enter_tabpage(curtab, curbuf, TRUE, TRUE);
3718     return FAIL;
3719 }
3720 
3721 /*
3722  * Open a new tab page if ":tab cmd" was used.  It will edit the same buffer,
3723  * like with ":split".
3724  * Returns OK if a new tab page was created, FAIL otherwise.
3725  */
3726     int
3727 may_open_tabpage(void)
3728 {
3729     int		n = (cmdmod.tab == 0) ? postponed_split_tab : cmdmod.tab;
3730 
3731     if (n != 0)
3732     {
3733 	cmdmod.tab = 0;	    /* reset it to avoid doing it twice */
3734 	postponed_split_tab = 0;
3735 	return win_new_tabpage(n);
3736     }
3737     return FAIL;
3738 }
3739 
3740 /*
3741  * Create up to "maxcount" tabpages with empty windows.
3742  * Returns the number of resulting tab pages.
3743  */
3744     int
3745 make_tabpages(int maxcount)
3746 {
3747     int		count = maxcount;
3748     int		todo;
3749 
3750     /* Limit to 'tabpagemax' tabs. */
3751     if (count > p_tpm)
3752 	count = p_tpm;
3753 
3754     /*
3755      * Don't execute autocommands while creating the tab pages.  Must do that
3756      * when putting the buffers in the windows.
3757      */
3758     block_autocmds();
3759 
3760     for (todo = count - 1; todo > 0; --todo)
3761 	if (win_new_tabpage(0) == FAIL)
3762 	    break;
3763 
3764     unblock_autocmds();
3765 
3766     /* return actual number of tab pages */
3767     return (count - todo);
3768 }
3769 
3770 /*
3771  * Return TRUE when "tpc" points to a valid tab page.
3772  */
3773     int
3774 valid_tabpage(tabpage_T *tpc)
3775 {
3776     tabpage_T	*tp;
3777 
3778     FOR_ALL_TABPAGES(tp)
3779 	if (tp == tpc)
3780 	    return TRUE;
3781     return FALSE;
3782 }
3783 
3784 /*
3785  * Return TRUE when "tpc" points to a valid tab page and at least one window is
3786  * valid.
3787  */
3788     int
3789 valid_tabpage_win(tabpage_T *tpc)
3790 {
3791     tabpage_T	*tp;
3792     win_T	*wp;
3793 
3794     FOR_ALL_TABPAGES(tp)
3795     {
3796 	if (tp == tpc)
3797 	{
3798 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
3799 	    {
3800 		if (win_valid_any_tab(wp))
3801 		    return TRUE;
3802 	    }
3803 	    return FALSE;
3804 	}
3805     }
3806     /* shouldn't happen */
3807     return FALSE;
3808 }
3809 
3810 /*
3811  * Close tabpage "tab", assuming it has no windows in it.
3812  * There must be another tabpage or this will crash.
3813  */
3814     void
3815 close_tabpage(tabpage_T *tab)
3816 {
3817     tabpage_T	*ptp;
3818 
3819     if (tab == first_tabpage)
3820     {
3821 	first_tabpage = tab->tp_next;
3822 	ptp = first_tabpage;
3823     }
3824     else
3825     {
3826 	for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tab;
3827 							    ptp = ptp->tp_next)
3828 	    ;
3829 	assert(ptp != NULL);
3830 	ptp->tp_next = tab->tp_next;
3831     }
3832 
3833     goto_tabpage_tp(ptp, FALSE, FALSE);
3834     free_tabpage(tab);
3835 }
3836 
3837 /*
3838  * Find tab page "n" (first one is 1).  Returns NULL when not found.
3839  */
3840     tabpage_T *
3841 find_tabpage(int n)
3842 {
3843     tabpage_T	*tp;
3844     int		i = 1;
3845 
3846     for (tp = first_tabpage; tp != NULL && i != n; tp = tp->tp_next)
3847 	++i;
3848     return tp;
3849 }
3850 
3851 /*
3852  * Get index of tab page "tp".  First one has index 1.
3853  * When not found returns number of tab pages plus one.
3854  */
3855     int
3856 tabpage_index(tabpage_T *ftp)
3857 {
3858     int		i = 1;
3859     tabpage_T	*tp;
3860 
3861     for (tp = first_tabpage; tp != NULL && tp != ftp; tp = tp->tp_next)
3862 	++i;
3863     return i;
3864 }
3865 
3866 /*
3867  * Prepare for leaving the current tab page.
3868  * When autocommands change "curtab" we don't leave the tab page and return
3869  * FAIL.
3870  * Careful: When OK is returned need to get a new tab page very very soon!
3871  */
3872     static int
3873 leave_tabpage(
3874     buf_T	*new_curbuf UNUSED,    /* what is going to be the new curbuf,
3875 				       NULL if unknown */
3876     int		trigger_leave_autocmds UNUSED)
3877 {
3878     tabpage_T	*tp = curtab;
3879 
3880 #ifdef FEAT_JOB_CHANNEL
3881     leaving_window(curwin);
3882 #endif
3883     reset_VIsual_and_resel();	/* stop Visual mode */
3884     if (trigger_leave_autocmds)
3885     {
3886 	if (new_curbuf != curbuf)
3887 	{
3888 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
3889 	    if (curtab != tp)
3890 		return FAIL;
3891 	}
3892 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
3893 	if (curtab != tp)
3894 	    return FAIL;
3895 	apply_autocmds(EVENT_TABLEAVE, NULL, NULL, FALSE, curbuf);
3896 	if (curtab != tp)
3897 	    return FAIL;
3898     }
3899 #if defined(FEAT_GUI)
3900     /* Remove the scrollbars.  They may be added back later. */
3901     if (gui.in_use)
3902 	gui_remove_scrollbars();
3903 #endif
3904     tp->tp_curwin = curwin;
3905     tp->tp_prevwin = prevwin;
3906     tp->tp_firstwin = firstwin;
3907     tp->tp_lastwin = lastwin;
3908     tp->tp_old_Rows = Rows;
3909     tp->tp_old_Columns = Columns;
3910     firstwin = NULL;
3911     lastwin = NULL;
3912     return OK;
3913 }
3914 
3915 /*
3916  * Start using tab page "tp".
3917  * Only to be used after leave_tabpage() or freeing the current tab page.
3918  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
3919  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
3920  */
3921     static void
3922 enter_tabpage(
3923     tabpage_T	*tp,
3924     buf_T	*old_curbuf UNUSED,
3925     int		trigger_enter_autocmds,
3926     int		trigger_leave_autocmds)
3927 {
3928     int		old_off = tp->tp_firstwin->w_winrow;
3929     win_T	*next_prevwin = tp->tp_prevwin;
3930 
3931     curtab = tp;
3932     firstwin = tp->tp_firstwin;
3933     lastwin = tp->tp_lastwin;
3934     topframe = tp->tp_topframe;
3935 
3936     /* We would like doing the TabEnter event first, but we don't have a
3937      * valid current window yet, which may break some commands.
3938      * This triggers autocommands, thus may make "tp" invalid. */
3939     win_enter_ext(tp->tp_curwin, FALSE, TRUE, FALSE,
3940 			      trigger_enter_autocmds, trigger_leave_autocmds);
3941     prevwin = next_prevwin;
3942 
3943     last_status(FALSE);		/* status line may appear or disappear */
3944     (void)win_comp_pos();	/* recompute w_winrow for all windows */
3945     must_redraw = CLEAR;	/* need to redraw everything */
3946 #ifdef FEAT_DIFF
3947     diff_need_scrollbind = TRUE;
3948 #endif
3949 
3950     /* The tabpage line may have appeared or disappeared, may need to resize
3951      * the frames for that.  When the Vim window was resized need to update
3952      * frame sizes too.  Use the stored value of p_ch, so that it can be
3953      * different for each tab page. */
3954     p_ch = curtab->tp_ch_used;
3955     if (curtab->tp_old_Rows != Rows || (old_off != firstwin->w_winrow
3956 #ifdef FEAT_GUI_TABLINE
3957 			    && !gui_use_tabline()
3958 #endif
3959 		))
3960 	shell_new_rows();
3961     if (curtab->tp_old_Columns != Columns && starting == 0)
3962 	shell_new_columns();	/* update window widths */
3963 
3964 #if defined(FEAT_GUI)
3965     /* When 'guioptions' includes 'L' or 'R' may have to remove or add
3966      * scrollbars.  Have to update them anyway. */
3967     gui_may_update_scrollbars();
3968 #endif
3969 
3970     /* Apply autocommands after updating the display, when 'rows' and
3971      * 'columns' have been set correctly. */
3972     if (trigger_enter_autocmds)
3973     {
3974 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3975 	if (old_curbuf != curbuf)
3976 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
3977     }
3978 
3979     redraw_all_later(CLEAR);
3980 }
3981 
3982 /*
3983  * Go to tab page "n".  For ":tab N" and "Ngt".
3984  * When "n" is 9999 go to the last tab page.
3985  */
3986     void
3987 goto_tabpage(int n)
3988 {
3989     tabpage_T	*tp;
3990     tabpage_T	*ttp;
3991     int		i;
3992 
3993     if (text_locked())
3994     {
3995 	/* Not allowed when editing the command line. */
3996 	text_locked_msg();
3997 	return;
3998     }
3999 
4000     /* If there is only one it can't work. */
4001     if (first_tabpage->tp_next == NULL)
4002     {
4003 	if (n > 1)
4004 	    beep_flush();
4005 	return;
4006     }
4007 
4008     if (n == 0)
4009     {
4010 	/* No count, go to next tab page, wrap around end. */
4011 	if (curtab->tp_next == NULL)
4012 	    tp = first_tabpage;
4013 	else
4014 	    tp = curtab->tp_next;
4015     }
4016     else if (n < 0)
4017     {
4018 	/* "gT": go to previous tab page, wrap around end.  "N gT" repeats
4019 	 * this N times. */
4020 	ttp = curtab;
4021 	for (i = n; i < 0; ++i)
4022 	{
4023 	    for (tp = first_tabpage; tp->tp_next != ttp && tp->tp_next != NULL;
4024 		    tp = tp->tp_next)
4025 		;
4026 	    ttp = tp;
4027 	}
4028     }
4029     else if (n == 9999)
4030     {
4031 	/* Go to last tab page. */
4032 	for (tp = first_tabpage; tp->tp_next != NULL; tp = tp->tp_next)
4033 	    ;
4034     }
4035     else
4036     {
4037 	/* Go to tab page "n". */
4038 	tp = find_tabpage(n);
4039 	if (tp == NULL)
4040 	{
4041 	    beep_flush();
4042 	    return;
4043 	}
4044     }
4045 
4046     goto_tabpage_tp(tp, TRUE, TRUE);
4047 
4048 #ifdef FEAT_GUI_TABLINE
4049     if (gui_use_tabline())
4050 	gui_mch_set_curtab(tabpage_index(curtab));
4051 #endif
4052 }
4053 
4054 /*
4055  * Go to tabpage "tp".
4056  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4057  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4058  * Note: doesn't update the GUI tab.
4059  */
4060     void
4061 goto_tabpage_tp(
4062     tabpage_T	*tp,
4063     int		trigger_enter_autocmds,
4064     int		trigger_leave_autocmds)
4065 {
4066     /* Don't repeat a message in another tab page. */
4067     set_keep_msg(NULL, 0);
4068 
4069     if (tp != curtab && leave_tabpage(tp->tp_curwin->w_buffer,
4070 					trigger_leave_autocmds) == OK)
4071     {
4072 	if (valid_tabpage(tp))
4073 	    enter_tabpage(tp, curbuf, trigger_enter_autocmds,
4074 		    trigger_leave_autocmds);
4075 	else
4076 	    enter_tabpage(curtab, curbuf, trigger_enter_autocmds,
4077 		    trigger_leave_autocmds);
4078     }
4079 }
4080 
4081 /*
4082  * Enter window "wp" in tab page "tp".
4083  * Also updates the GUI tab.
4084  */
4085     void
4086 goto_tabpage_win(tabpage_T *tp, win_T *wp)
4087 {
4088     goto_tabpage_tp(tp, TRUE, TRUE);
4089     if (curtab == tp && win_valid(wp))
4090     {
4091 	win_enter(wp, TRUE);
4092 # ifdef FEAT_GUI_TABLINE
4093 	if (gui_use_tabline())
4094 	    gui_mch_set_curtab(tabpage_index(curtab));
4095 # endif
4096     }
4097 }
4098 
4099 /*
4100  * Move the current tab page to after tab page "nr".
4101  */
4102     void
4103 tabpage_move(int nr)
4104 {
4105     int		n = 1;
4106     tabpage_T	*tp, *tp_dst;
4107 
4108     if (first_tabpage->tp_next == NULL)
4109 	return;
4110 
4111     for (tp = first_tabpage; tp->tp_next != NULL && n < nr; tp = tp->tp_next)
4112 	++n;
4113 
4114     if (tp == curtab || (nr > 0 && tp->tp_next != NULL
4115 						    && tp->tp_next == curtab))
4116 	return;
4117 
4118     tp_dst = tp;
4119 
4120     /* Remove the current tab page from the list of tab pages. */
4121     if (curtab == first_tabpage)
4122 	first_tabpage = curtab->tp_next;
4123     else
4124     {
4125 	FOR_ALL_TABPAGES(tp)
4126 	    if (tp->tp_next == curtab)
4127 		break;
4128 	if (tp == NULL)	/* "cannot happen" */
4129 	    return;
4130 	tp->tp_next = curtab->tp_next;
4131     }
4132 
4133     /* Re-insert it at the specified position. */
4134     if (nr <= 0)
4135     {
4136 	curtab->tp_next = first_tabpage;
4137 	first_tabpage = curtab;
4138     }
4139     else
4140     {
4141 	curtab->tp_next = tp_dst->tp_next;
4142 	tp_dst->tp_next = curtab;
4143     }
4144 
4145     /* Need to redraw the tabline.  Tab page contents doesn't change. */
4146     redraw_tabline = TRUE;
4147 }
4148 
4149 
4150 /*
4151  * Go to another window.
4152  * When jumping to another buffer, stop Visual mode.  Do this before
4153  * changing windows so we can yank the selection into the '*' register.
4154  * When jumping to another window on the same buffer, adjust its cursor
4155  * position to keep the same Visual area.
4156  */
4157     void
4158 win_goto(win_T *wp)
4159 {
4160 #ifdef FEAT_CONCEAL
4161     win_T	*owp = curwin;
4162 #endif
4163 
4164     if (text_locked())
4165     {
4166 	beep_flush();
4167 	text_locked_msg();
4168 	return;
4169     }
4170     if (curbuf_locked())
4171 	return;
4172 
4173     if (wp->w_buffer != curbuf)
4174 	reset_VIsual_and_resel();
4175     else if (VIsual_active)
4176 	wp->w_cursor = curwin->w_cursor;
4177 
4178 #ifdef FEAT_GUI
4179     need_mouse_correct = TRUE;
4180 #endif
4181     win_enter(wp, TRUE);
4182 
4183 #ifdef FEAT_CONCEAL
4184     /* Conceal cursor line in previous window, unconceal in current window. */
4185     if (win_valid(owp) && owp->w_p_cole > 0 && !msg_scrolled)
4186 	update_single_line(owp, owp->w_cursor.lnum);
4187     if (curwin->w_p_cole > 0 && !msg_scrolled)
4188 	need_cursor_line_redraw = TRUE;
4189 #endif
4190 }
4191 
4192 #if defined(FEAT_PERL) || defined(PROTO)
4193 /*
4194  * Find window number "winnr" (counting top to bottom).
4195  */
4196     win_T *
4197 win_find_nr(int winnr)
4198 {
4199     win_T	*wp;
4200 
4201     FOR_ALL_WINDOWS(wp)
4202 	if (--winnr == 0)
4203 	    break;
4204     return wp;
4205 }
4206 #endif
4207 
4208 #if ((defined(FEAT_PYTHON) || defined(FEAT_PYTHON3))) || defined(PROTO)
4209 /*
4210  * Find the tabpage for window "win".
4211  */
4212     tabpage_T *
4213 win_find_tabpage(win_T *win)
4214 {
4215     win_T	*wp;
4216     tabpage_T	*tp;
4217 
4218     FOR_ALL_TAB_WINDOWS(tp, wp)
4219 	    if (wp == win)
4220 		return tp;
4221     return NULL;
4222 }
4223 #endif
4224 
4225 /*
4226  * Move to window above or below "count" times.
4227  */
4228     static void
4229 win_goto_ver(
4230     int		up,		/* TRUE to go to win above */
4231     long	count)
4232 {
4233     frame_T	*fr;
4234     frame_T	*nfr;
4235     frame_T	*foundfr;
4236 
4237     foundfr = curwin->w_frame;
4238     while (count--)
4239     {
4240 	/*
4241 	 * First go upwards in the tree of frames until we find a upwards or
4242 	 * downwards neighbor.
4243 	 */
4244 	fr = foundfr;
4245 	for (;;)
4246 	{
4247 	    if (fr == topframe)
4248 		goto end;
4249 	    if (up)
4250 		nfr = fr->fr_prev;
4251 	    else
4252 		nfr = fr->fr_next;
4253 	    if (fr->fr_parent->fr_layout == FR_COL && nfr != NULL)
4254 		break;
4255 	    fr = fr->fr_parent;
4256 	}
4257 
4258 	/*
4259 	 * Now go downwards to find the bottom or top frame in it.
4260 	 */
4261 	for (;;)
4262 	{
4263 	    if (nfr->fr_layout == FR_LEAF)
4264 	    {
4265 		foundfr = nfr;
4266 		break;
4267 	    }
4268 	    fr = nfr->fr_child;
4269 	    if (nfr->fr_layout == FR_ROW)
4270 	    {
4271 		/* Find the frame at the cursor row. */
4272 		while (fr->fr_next != NULL
4273 			&& frame2win(fr)->w_wincol + fr->fr_width
4274 					 <= curwin->w_wincol + curwin->w_wcol)
4275 		    fr = fr->fr_next;
4276 	    }
4277 	    if (nfr->fr_layout == FR_COL && up)
4278 		while (fr->fr_next != NULL)
4279 		    fr = fr->fr_next;
4280 	    nfr = fr;
4281 	}
4282     }
4283 end:
4284     if (foundfr != NULL)
4285 	win_goto(foundfr->fr_win);
4286 }
4287 
4288 /*
4289  * Move to left or right window.
4290  */
4291     static void
4292 win_goto_hor(
4293     int		left,		/* TRUE to go to left win */
4294     long	count)
4295 {
4296     frame_T	*fr;
4297     frame_T	*nfr;
4298     frame_T	*foundfr;
4299 
4300     foundfr = curwin->w_frame;
4301     while (count--)
4302     {
4303 	/*
4304 	 * First go upwards in the tree of frames until we find a left or
4305 	 * right neighbor.
4306 	 */
4307 	fr = foundfr;
4308 	for (;;)
4309 	{
4310 	    if (fr == topframe)
4311 		goto end;
4312 	    if (left)
4313 		nfr = fr->fr_prev;
4314 	    else
4315 		nfr = fr->fr_next;
4316 	    if (fr->fr_parent->fr_layout == FR_ROW && nfr != NULL)
4317 		break;
4318 	    fr = fr->fr_parent;
4319 	}
4320 
4321 	/*
4322 	 * Now go downwards to find the leftmost or rightmost frame in it.
4323 	 */
4324 	for (;;)
4325 	{
4326 	    if (nfr->fr_layout == FR_LEAF)
4327 	    {
4328 		foundfr = nfr;
4329 		break;
4330 	    }
4331 	    fr = nfr->fr_child;
4332 	    if (nfr->fr_layout == FR_COL)
4333 	    {
4334 		/* Find the frame at the cursor row. */
4335 		while (fr->fr_next != NULL
4336 			&& frame2win(fr)->w_winrow + fr->fr_height
4337 					 <= curwin->w_winrow + curwin->w_wrow)
4338 		    fr = fr->fr_next;
4339 	    }
4340 	    if (nfr->fr_layout == FR_ROW && left)
4341 		while (fr->fr_next != NULL)
4342 		    fr = fr->fr_next;
4343 	    nfr = fr;
4344 	}
4345     }
4346 end:
4347     if (foundfr != NULL)
4348 	win_goto(foundfr->fr_win);
4349 }
4350 
4351 /*
4352  * Make window "wp" the current window.
4353  */
4354     void
4355 win_enter(win_T *wp, int undo_sync)
4356 {
4357     win_enter_ext(wp, undo_sync, FALSE, FALSE, TRUE, TRUE);
4358 }
4359 
4360 /*
4361  * Make window wp the current window.
4362  * Can be called with "curwin_invalid" TRUE, which means that curwin has just
4363  * been closed and isn't valid.
4364  */
4365     static void
4366 win_enter_ext(
4367     win_T	*wp,
4368     int		undo_sync,
4369     int		curwin_invalid,
4370     int		trigger_new_autocmds,
4371     int		trigger_enter_autocmds,
4372     int		trigger_leave_autocmds)
4373 {
4374     int		other_buffer = FALSE;
4375 
4376     if (wp == curwin && !curwin_invalid)	/* nothing to do */
4377 	return;
4378 
4379 #ifdef FEAT_JOB_CHANNEL
4380     if (!curwin_invalid)
4381 	leaving_window(curwin);
4382 #endif
4383 
4384     if (!curwin_invalid && trigger_leave_autocmds)
4385     {
4386 	/*
4387 	 * Be careful: If autocommands delete the window, return now.
4388 	 */
4389 	if (wp->w_buffer != curbuf)
4390 	{
4391 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4392 	    other_buffer = TRUE;
4393 	    if (!win_valid(wp))
4394 		return;
4395 	}
4396 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4397 	if (!win_valid(wp))
4398 	    return;
4399 #ifdef FEAT_EVAL
4400 	/* autocmds may abort script processing */
4401 	if (aborting())
4402 	    return;
4403 #endif
4404     }
4405 
4406     /* sync undo before leaving the current buffer */
4407     if (undo_sync && curbuf != wp->w_buffer)
4408 	u_sync(FALSE);
4409 
4410     /* Might need to scroll the old window before switching, e.g., when the
4411      * cursor was moved. */
4412     update_topline();
4413 
4414     /* may have to copy the buffer options when 'cpo' contains 'S' */
4415     if (wp->w_buffer != curbuf)
4416 	buf_copy_options(wp->w_buffer, BCO_ENTER | BCO_NOHELP);
4417     if (!curwin_invalid)
4418     {
4419 	prevwin = curwin;	/* remember for CTRL-W p */
4420 	curwin->w_redr_status = TRUE;
4421     }
4422     curwin = wp;
4423     curbuf = wp->w_buffer;
4424     check_cursor();
4425 #ifdef FEAT_VIRTUALEDIT
4426     if (!virtual_active())
4427 	curwin->w_cursor.coladd = 0;
4428 #endif
4429     changed_line_abv_curs();	/* assume cursor position needs updating */
4430 
4431     if (curwin->w_localdir != NULL)
4432     {
4433 	/* Window has a local directory: Save current directory as global
4434 	 * directory (unless that was done already) and change to the local
4435 	 * directory. */
4436 	if (globaldir == NULL)
4437 	{
4438 	    char_u	cwd[MAXPATHL];
4439 
4440 	    if (mch_dirname(cwd, MAXPATHL) == OK)
4441 		globaldir = vim_strsave(cwd);
4442 	}
4443 	if (mch_chdir((char *)curwin->w_localdir) == 0)
4444 	    shorten_fnames(TRUE);
4445     }
4446     else if (globaldir != NULL)
4447     {
4448 	/* Window doesn't have a local directory and we are not in the global
4449 	 * directory: Change to the global directory. */
4450 	vim_ignored = mch_chdir((char *)globaldir);
4451 	VIM_CLEAR(globaldir);
4452 	shorten_fnames(TRUE);
4453     }
4454 
4455 #ifdef FEAT_JOB_CHANNEL
4456     entering_window(curwin);
4457 #endif
4458     if (trigger_new_autocmds)
4459 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
4460     if (trigger_enter_autocmds)
4461     {
4462 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
4463 	if (other_buffer)
4464 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4465     }
4466 
4467 #ifdef FEAT_TITLE
4468     maketitle();
4469 #endif
4470     curwin->w_redr_status = TRUE;
4471     redraw_tabline = TRUE;
4472     if (restart_edit)
4473 	redraw_later(VALID);	/* causes status line redraw */
4474 
4475     /* set window height to desired minimal value */
4476     if (curwin->w_height < p_wh && !curwin->w_p_wfh)
4477 	win_setheight((int)p_wh);
4478     else if (curwin->w_height == 0)
4479 	win_setheight(1);
4480 
4481     /* set window width to desired minimal value */
4482     if (curwin->w_width < p_wiw && !curwin->w_p_wfw)
4483 	win_setwidth((int)p_wiw);
4484 
4485 #ifdef FEAT_MOUSE
4486     setmouse();			/* in case jumped to/from help buffer */
4487 #endif
4488 
4489     /* Change directories when the 'acd' option is set. */
4490     DO_AUTOCHDIR;
4491 }
4492 
4493 
4494 /*
4495  * Jump to the first open window that contains buffer "buf", if one exists.
4496  * Returns a pointer to the window found, otherwise NULL.
4497  */
4498     win_T *
4499 buf_jump_open_win(buf_T *buf)
4500 {
4501     win_T	*wp = NULL;
4502 
4503     if (curwin->w_buffer == buf)
4504 	wp = curwin;
4505     else
4506 	FOR_ALL_WINDOWS(wp)
4507 	    if (wp->w_buffer == buf)
4508 		break;
4509     if (wp != NULL)
4510 	win_enter(wp, FALSE);
4511     return wp;
4512 }
4513 
4514 /*
4515  * Jump to the first open window in any tab page that contains buffer "buf",
4516  * if one exists.
4517  * Returns a pointer to the window found, otherwise NULL.
4518  */
4519     win_T *
4520 buf_jump_open_tab(buf_T *buf)
4521 {
4522     win_T	*wp = buf_jump_open_win(buf);
4523     tabpage_T	*tp;
4524 
4525     if (wp != NULL)
4526 	return wp;
4527 
4528     FOR_ALL_TABPAGES(tp)
4529 	if (tp != curtab)
4530 	{
4531 	    for (wp = tp->tp_firstwin; wp != NULL; wp = wp->w_next)
4532 		if (wp->w_buffer == buf)
4533 		    break;
4534 	    if (wp != NULL)
4535 	    {
4536 		goto_tabpage_win(tp, wp);
4537 		if (curwin != wp)
4538 		    wp = NULL;	/* something went wrong */
4539 		break;
4540 	    }
4541 	}
4542     return wp;
4543 }
4544 
4545 static int last_win_id = LOWEST_WIN_ID - 1;
4546 
4547 /*
4548  * Allocate a window structure and link it in the window list when "hidden" is
4549  * FALSE.
4550  */
4551     static win_T *
4552 win_alloc(win_T *after UNUSED, int hidden UNUSED)
4553 {
4554     win_T	*new_wp;
4555 
4556     /*
4557      * allocate window structure and linesizes arrays
4558      */
4559     new_wp = (win_T *)alloc_clear((unsigned)sizeof(win_T));
4560     if (new_wp == NULL)
4561 	return NULL;
4562 
4563     if (win_alloc_lines(new_wp) == FAIL)
4564     {
4565 	vim_free(new_wp);
4566 	return NULL;
4567     }
4568 
4569     new_wp->w_id = ++last_win_id;
4570 
4571 #ifdef FEAT_EVAL
4572     /* init w: variables */
4573     new_wp->w_vars = dict_alloc();
4574     if (new_wp->w_vars == NULL)
4575     {
4576 	win_free_lsize(new_wp);
4577 	vim_free(new_wp);
4578 	return NULL;
4579     }
4580     init_var_dict(new_wp->w_vars, &new_wp->w_winvar, VAR_SCOPE);
4581 #endif
4582 
4583     /* Don't execute autocommands while the window is not properly
4584      * initialized yet.  gui_create_scrollbar() may trigger a FocusGained
4585      * event. */
4586     block_autocmds();
4587 
4588     /*
4589      * link the window in the window list
4590      */
4591     if (!hidden)
4592 	win_append(after, new_wp);
4593     new_wp->w_wincol = 0;
4594     new_wp->w_width = Columns;
4595 
4596     /* position the display and the cursor at the top of the file. */
4597     new_wp->w_topline = 1;
4598 #ifdef FEAT_DIFF
4599     new_wp->w_topfill = 0;
4600 #endif
4601     new_wp->w_botline = 2;
4602     new_wp->w_cursor.lnum = 1;
4603     new_wp->w_scbind_pos = 1;
4604 
4605     /* We won't calculate w_fraction until resizing the window */
4606     new_wp->w_fraction = 0;
4607     new_wp->w_prev_fraction_row = -1;
4608 
4609 #ifdef FEAT_GUI
4610     if (gui.in_use)
4611     {
4612 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_LEFT],
4613 		SBAR_LEFT, new_wp);
4614 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_RIGHT],
4615 		SBAR_RIGHT, new_wp);
4616     }
4617 #endif
4618 #ifdef FEAT_FOLDING
4619     foldInitWin(new_wp);
4620 #endif
4621     unblock_autocmds();
4622 #ifdef FEAT_SEARCH_EXTRA
4623     new_wp->w_match_head = NULL;
4624     new_wp->w_next_match_id = 4;
4625 #endif
4626     return new_wp;
4627 }
4628 
4629 /*
4630  * Remove window 'wp' from the window list and free the structure.
4631  */
4632     static void
4633 win_free(
4634     win_T	*wp,
4635     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
4636 {
4637     int		i;
4638     buf_T	*buf;
4639     wininfo_T	*wip;
4640 
4641 #ifdef FEAT_FOLDING
4642     clearFolding(wp);
4643 #endif
4644 
4645     /* reduce the reference count to the argument list. */
4646     alist_unlink(wp->w_alist);
4647 
4648     /* Don't execute autocommands while the window is halfway being deleted.
4649      * gui_mch_destroy_scrollbar() may trigger a FocusGained event. */
4650     block_autocmds();
4651 
4652 #ifdef FEAT_LUA
4653     lua_window_free(wp);
4654 #endif
4655 
4656 #ifdef FEAT_MZSCHEME
4657     mzscheme_window_free(wp);
4658 #endif
4659 
4660 #ifdef FEAT_PERL
4661     perl_win_free(wp);
4662 #endif
4663 
4664 #ifdef FEAT_PYTHON
4665     python_window_free(wp);
4666 #endif
4667 
4668 #ifdef FEAT_PYTHON3
4669     python3_window_free(wp);
4670 #endif
4671 
4672 #ifdef FEAT_TCL
4673     tcl_window_free(wp);
4674 #endif
4675 
4676 #ifdef FEAT_RUBY
4677     ruby_window_free(wp);
4678 #endif
4679 
4680     clear_winopt(&wp->w_onebuf_opt);
4681     clear_winopt(&wp->w_allbuf_opt);
4682 
4683 #ifdef FEAT_EVAL
4684     vars_clear(&wp->w_vars->dv_hashtab);	/* free all w: variables */
4685     hash_init(&wp->w_vars->dv_hashtab);
4686     unref_var_dict(wp->w_vars);
4687 #endif
4688 
4689     {
4690 	tabpage_T	*ttp;
4691 
4692 	if (prevwin == wp)
4693 	    prevwin = NULL;
4694 	FOR_ALL_TABPAGES(ttp)
4695 	    if (ttp->tp_prevwin == wp)
4696 		ttp->tp_prevwin = NULL;
4697     }
4698     win_free_lsize(wp);
4699 
4700     for (i = 0; i < wp->w_tagstacklen; ++i)
4701 	vim_free(wp->w_tagstack[i].tagname);
4702 
4703     vim_free(wp->w_localdir);
4704 
4705     /* Remove the window from the b_wininfo lists, it may happen that the
4706      * freed memory is re-used for another window. */
4707     FOR_ALL_BUFFERS(buf)
4708 	for (wip = buf->b_wininfo; wip != NULL; wip = wip->wi_next)
4709 	    if (wip->wi_win == wp)
4710 		wip->wi_win = NULL;
4711 
4712 #ifdef FEAT_SEARCH_EXTRA
4713     clear_matches(wp);
4714 #endif
4715 
4716 #ifdef FEAT_JUMPLIST
4717     free_jumplist(wp);
4718 #endif
4719 
4720 #ifdef FEAT_QUICKFIX
4721     qf_free_all(wp);
4722 #endif
4723 
4724 #ifdef FEAT_GUI
4725     if (gui.in_use)
4726     {
4727 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_LEFT]);
4728 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_RIGHT]);
4729     }
4730 #endif /* FEAT_GUI */
4731 
4732 #ifdef FEAT_MENU
4733     remove_winbar(wp);
4734 #endif
4735 
4736 #ifdef FEAT_SYN_HL
4737     vim_free(wp->w_p_cc_cols);
4738 #endif
4739 
4740     if (wp != aucmd_win)
4741 	win_remove(wp, tp);
4742     if (autocmd_busy)
4743     {
4744 	wp->w_next = au_pending_free_win;
4745 	au_pending_free_win = wp;
4746     }
4747     else
4748 	vim_free(wp);
4749 
4750     unblock_autocmds();
4751 }
4752 
4753 /*
4754  * Append window "wp" in the window list after window "after".
4755  */
4756     void
4757 win_append(win_T *after, win_T *wp)
4758 {
4759     win_T	*before;
4760 
4761     if (after == NULL)	    /* after NULL is in front of the first */
4762 	before = firstwin;
4763     else
4764 	before = after->w_next;
4765 
4766     wp->w_next = before;
4767     wp->w_prev = after;
4768     if (after == NULL)
4769 	firstwin = wp;
4770     else
4771 	after->w_next = wp;
4772     if (before == NULL)
4773 	lastwin = wp;
4774     else
4775 	before->w_prev = wp;
4776 }
4777 
4778 /*
4779  * Remove a window from the window list.
4780  */
4781     void
4782 win_remove(
4783     win_T	*wp,
4784     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
4785 {
4786     if (wp->w_prev != NULL)
4787 	wp->w_prev->w_next = wp->w_next;
4788     else if (tp == NULL)
4789 	firstwin = curtab->tp_firstwin = wp->w_next;
4790     else
4791 	tp->tp_firstwin = wp->w_next;
4792 
4793     if (wp->w_next != NULL)
4794 	wp->w_next->w_prev = wp->w_prev;
4795     else if (tp == NULL)
4796 	lastwin = curtab->tp_lastwin = wp->w_prev;
4797     else
4798 	tp->tp_lastwin = wp->w_prev;
4799 }
4800 
4801 /*
4802  * Append frame "frp" in a frame list after frame "after".
4803  */
4804     static void
4805 frame_append(frame_T *after, frame_T *frp)
4806 {
4807     frp->fr_next = after->fr_next;
4808     after->fr_next = frp;
4809     if (frp->fr_next != NULL)
4810 	frp->fr_next->fr_prev = frp;
4811     frp->fr_prev = after;
4812 }
4813 
4814 /*
4815  * Insert frame "frp" in a frame list before frame "before".
4816  */
4817     static void
4818 frame_insert(frame_T *before, frame_T *frp)
4819 {
4820     frp->fr_next = before;
4821     frp->fr_prev = before->fr_prev;
4822     before->fr_prev = frp;
4823     if (frp->fr_prev != NULL)
4824 	frp->fr_prev->fr_next = frp;
4825     else
4826 	frp->fr_parent->fr_child = frp;
4827 }
4828 
4829 /*
4830  * Remove a frame from a frame list.
4831  */
4832     static void
4833 frame_remove(frame_T *frp)
4834 {
4835     if (frp->fr_prev != NULL)
4836 	frp->fr_prev->fr_next = frp->fr_next;
4837     else
4838     {
4839 	frp->fr_parent->fr_child = frp->fr_next;
4840 	/* special case: topframe->fr_child == frp */
4841 	if (topframe->fr_child == frp)
4842 	    topframe->fr_child = frp->fr_next;
4843     }
4844     if (frp->fr_next != NULL)
4845 	frp->fr_next->fr_prev = frp->fr_prev;
4846 }
4847 
4848 /*
4849  * Allocate w_lines[] for window "wp".
4850  * Return FAIL for failure, OK for success.
4851  */
4852     int
4853 win_alloc_lines(win_T *wp)
4854 {
4855     wp->w_lines_valid = 0;
4856     wp->w_lines = (wline_T *)alloc_clear((unsigned)(Rows * sizeof(wline_T)));
4857     if (wp->w_lines == NULL)
4858 	return FAIL;
4859     return OK;
4860 }
4861 
4862 /*
4863  * free lsize arrays for a window
4864  */
4865     void
4866 win_free_lsize(win_T *wp)
4867 {
4868     /* TODO: why would wp be NULL here? */
4869     if (wp != NULL)
4870 	VIM_CLEAR(wp->w_lines);
4871 }
4872 
4873 /*
4874  * Called from win_new_shellsize() after Rows changed.
4875  * This only does the current tab page, others must be done when made active.
4876  */
4877     void
4878 shell_new_rows(void)
4879 {
4880     int		h = (int)ROWS_AVAIL;
4881 
4882     if (firstwin == NULL)	/* not initialized yet */
4883 	return;
4884     if (h < frame_minheight(topframe, NULL))
4885 	h = frame_minheight(topframe, NULL);
4886 
4887     /* First try setting the heights of windows with 'winfixheight'.  If
4888      * that doesn't result in the right height, forget about that option. */
4889     frame_new_height(topframe, h, FALSE, TRUE);
4890     if (!frame_check_height(topframe, h))
4891 	frame_new_height(topframe, h, FALSE, FALSE);
4892 
4893     (void)win_comp_pos();		/* recompute w_winrow and w_wincol */
4894     compute_cmdrow();
4895     curtab->tp_ch_used = p_ch;
4896 
4897 #if 0
4898     /* Disabled: don't want making the screen smaller make a window larger. */
4899     if (p_ea)
4900 	win_equal(curwin, FALSE, 'v');
4901 #endif
4902 }
4903 
4904 /*
4905  * Called from win_new_shellsize() after Columns changed.
4906  */
4907     void
4908 shell_new_columns(void)
4909 {
4910     if (firstwin == NULL)	/* not initialized yet */
4911 	return;
4912 
4913     /* First try setting the widths of windows with 'winfixwidth'.  If that
4914      * doesn't result in the right width, forget about that option. */
4915     frame_new_width(topframe, (int)Columns, FALSE, TRUE);
4916     if (!frame_check_width(topframe, Columns))
4917 	frame_new_width(topframe, (int)Columns, FALSE, FALSE);
4918 
4919     (void)win_comp_pos();		/* recompute w_winrow and w_wincol */
4920 #if 0
4921     /* Disabled: don't want making the screen smaller make a window larger. */
4922     if (p_ea)
4923 	win_equal(curwin, FALSE, 'h');
4924 #endif
4925 }
4926 
4927 #if defined(FEAT_CMDWIN) || defined(PROTO)
4928 /*
4929  * Save the size of all windows in "gap".
4930  */
4931     void
4932 win_size_save(garray_T *gap)
4933 
4934 {
4935     win_T	*wp;
4936 
4937     ga_init2(gap, (int)sizeof(int), 1);
4938     if (ga_grow(gap, win_count() * 2) == OK)
4939 	FOR_ALL_WINDOWS(wp)
4940 	{
4941 	    ((int *)gap->ga_data)[gap->ga_len++] =
4942 					       wp->w_width + wp->w_vsep_width;
4943 	    ((int *)gap->ga_data)[gap->ga_len++] = wp->w_height;
4944 	}
4945 }
4946 
4947 /*
4948  * Restore window sizes, but only if the number of windows is still the same.
4949  * Does not free the growarray.
4950  */
4951     void
4952 win_size_restore(garray_T *gap)
4953 {
4954     win_T	*wp;
4955     int		i, j;
4956 
4957     if (win_count() * 2 == gap->ga_len)
4958     {
4959 	/* The order matters, because frames contain other frames, but it's
4960 	 * difficult to get right. The easy way out is to do it twice. */
4961 	for (j = 0; j < 2; ++j)
4962 	{
4963 	    i = 0;
4964 	    FOR_ALL_WINDOWS(wp)
4965 	    {
4966 		frame_setwidth(wp->w_frame, ((int *)gap->ga_data)[i++]);
4967 		win_setheight_win(((int *)gap->ga_data)[i++], wp);
4968 	    }
4969 	}
4970 	/* recompute the window positions */
4971 	(void)win_comp_pos();
4972     }
4973 }
4974 #endif /* FEAT_CMDWIN */
4975 
4976 /*
4977  * Update the position for all windows, using the width and height of the
4978  * frames.
4979  * Returns the row just after the last window.
4980  */
4981     int
4982 win_comp_pos(void)
4983 {
4984     int		row = tabline_height();
4985     int		col = 0;
4986 
4987     frame_comp_pos(topframe, &row, &col);
4988     return row;
4989 }
4990 
4991 /*
4992  * Update the position of the windows in frame "topfrp", using the width and
4993  * height of the frames.
4994  * "*row" and "*col" are the top-left position of the frame.  They are updated
4995  * to the bottom-right position plus one.
4996  */
4997     static void
4998 frame_comp_pos(frame_T *topfrp, int *row, int *col)
4999 {
5000     win_T	*wp;
5001     frame_T	*frp;
5002     int		startcol;
5003     int		startrow;
5004     int		h;
5005 
5006     wp = topfrp->fr_win;
5007     if (wp != NULL)
5008     {
5009 	if (wp->w_winrow != *row || wp->w_wincol != *col)
5010 	{
5011 	    /* position changed, redraw */
5012 	    wp->w_winrow = *row;
5013 	    wp->w_wincol = *col;
5014 	    redraw_win_later(wp, NOT_VALID);
5015 	    wp->w_redr_status = TRUE;
5016 	}
5017 	/* WinBar will not show if the window height is zero */
5018 	h = VISIBLE_HEIGHT(wp) + wp->w_status_height;
5019 	*row += h > topfrp->fr_height ? topfrp->fr_height : h;
5020 	*col += wp->w_width + wp->w_vsep_width;
5021     }
5022     else
5023     {
5024 	startrow = *row;
5025 	startcol = *col;
5026 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
5027 	{
5028 	    if (topfrp->fr_layout == FR_ROW)
5029 		*row = startrow;	/* all frames are at the same row */
5030 	    else
5031 		*col = startcol;	/* all frames are at the same col */
5032 	    frame_comp_pos(frp, row, col);
5033 	}
5034     }
5035 }
5036 
5037 /*
5038  * Set current window height and take care of repositioning other windows to
5039  * fit around it.
5040  */
5041     void
5042 win_setheight(int height)
5043 {
5044     win_setheight_win(height, curwin);
5045 }
5046 
5047 /*
5048  * Set the window height of window "win" and take care of repositioning other
5049  * windows to fit around it.
5050  */
5051     void
5052 win_setheight_win(int height, win_T *win)
5053 {
5054     int		row;
5055 
5056     if (win == curwin)
5057     {
5058 	/* Always keep current window at least one line high, even when
5059 	 * 'winminheight' is zero. */
5060 	if (height < p_wmh)
5061 	    height = p_wmh;
5062 	if (height == 0)
5063 	    height = 1;
5064 	height += WINBAR_HEIGHT(curwin);
5065     }
5066 
5067     frame_setheight(win->w_frame, height + win->w_status_height);
5068 
5069     /* recompute the window positions */
5070     row = win_comp_pos();
5071 
5072     /*
5073      * If there is extra space created between the last window and the command
5074      * line, clear it.
5075      */
5076     if (full_screen && msg_scrolled == 0 && row < cmdline_row)
5077 	screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5078     cmdline_row = row;
5079     msg_row = row;
5080     msg_col = 0;
5081 
5082     redraw_all_later(NOT_VALID);
5083 }
5084 
5085 /*
5086  * Set the height of a frame to "height" and take care that all frames and
5087  * windows inside it are resized.  Also resize frames on the left and right if
5088  * the are in the same FR_ROW frame.
5089  *
5090  * Strategy:
5091  * If the frame is part of a FR_COL frame, try fitting the frame in that
5092  * frame.  If that doesn't work (the FR_COL frame is too small), recursively
5093  * go to containing frames to resize them and make room.
5094  * If the frame is part of a FR_ROW frame, all frames must be resized as well.
5095  * Check for the minimal height of the FR_ROW frame.
5096  * At the top level we can also use change the command line height.
5097  */
5098     static void
5099 frame_setheight(frame_T *curfrp, int height)
5100 {
5101     int		room;		/* total number of lines available */
5102     int		take;		/* number of lines taken from other windows */
5103     int		room_cmdline;	/* lines available from cmdline */
5104     int		run;
5105     frame_T	*frp;
5106     int		h;
5107     int		room_reserved;
5108 
5109     /* If the height already is the desired value, nothing to do. */
5110     if (curfrp->fr_height == height)
5111 	return;
5112 
5113     if (curfrp->fr_parent == NULL)
5114     {
5115 	/* topframe: can only change the command line */
5116 	if (height > ROWS_AVAIL)
5117 	    height = ROWS_AVAIL;
5118 	if (height > 0)
5119 	    frame_new_height(curfrp, height, FALSE, FALSE);
5120     }
5121     else if (curfrp->fr_parent->fr_layout == FR_ROW)
5122     {
5123 	/* Row of frames: Also need to resize frames left and right of this
5124 	 * one.  First check for the minimal height of these. */
5125 	h = frame_minheight(curfrp->fr_parent, NULL);
5126 	if (height < h)
5127 	    height = h;
5128 	frame_setheight(curfrp->fr_parent, height);
5129     }
5130     else
5131     {
5132 	/*
5133 	 * Column of frames: try to change only frames in this column.
5134 	 */
5135 	/*
5136 	 * Do this twice:
5137 	 * 1: compute room available, if it's not enough try resizing the
5138 	 *    containing frame.
5139 	 * 2: compute the room available and adjust the height to it.
5140 	 * Try not to reduce the height of a window with 'winfixheight' set.
5141 	 */
5142 	for (run = 1; run <= 2; ++run)
5143 	{
5144 	    room = 0;
5145 	    room_reserved = 0;
5146 	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
5147 							   frp = frp->fr_next)
5148 	    {
5149 		if (frp != curfrp
5150 			&& frp->fr_win != NULL
5151 			&& frp->fr_win->w_p_wfh)
5152 		    room_reserved += frp->fr_height;
5153 		room += frp->fr_height;
5154 		if (frp != curfrp)
5155 		    room -= frame_minheight(frp, NULL);
5156 	    }
5157 	    if (curfrp->fr_width != Columns)
5158 		room_cmdline = 0;
5159 	    else
5160 	    {
5161 		room_cmdline = Rows - p_ch - (lastwin->w_winrow
5162 						+ VISIBLE_HEIGHT(lastwin)
5163 						+ lastwin->w_status_height);
5164 		if (room_cmdline < 0)
5165 		    room_cmdline = 0;
5166 	    }
5167 
5168 	    if (height <= room + room_cmdline)
5169 		break;
5170 	    if (run == 2 || curfrp->fr_width == Columns)
5171 	    {
5172 		if (height > room + room_cmdline)
5173 		    height = room + room_cmdline;
5174 		break;
5175 	    }
5176 	    frame_setheight(curfrp->fr_parent, height
5177 		+ frame_minheight(curfrp->fr_parent, NOWIN) - (int)p_wmh - 1);
5178 	}
5179 
5180 	/*
5181 	 * Compute the number of lines we will take from others frames (can be
5182 	 * negative!).
5183 	 */
5184 	take = height - curfrp->fr_height;
5185 
5186 	/* If there is not enough room, also reduce the height of a window
5187 	 * with 'winfixheight' set. */
5188 	if (height > room + room_cmdline - room_reserved)
5189 	    room_reserved = room + room_cmdline - height;
5190 	/* If there is only a 'winfixheight' window and making the
5191 	 * window smaller, need to make the other window taller. */
5192 	if (take < 0 && room - curfrp->fr_height < room_reserved)
5193 	    room_reserved = 0;
5194 
5195 	if (take > 0 && room_cmdline > 0)
5196 	{
5197 	    /* use lines from cmdline first */
5198 	    if (take < room_cmdline)
5199 		room_cmdline = take;
5200 	    take -= room_cmdline;
5201 	    topframe->fr_height += room_cmdline;
5202 	}
5203 
5204 	/*
5205 	 * set the current frame to the new height
5206 	 */
5207 	frame_new_height(curfrp, height, FALSE, FALSE);
5208 
5209 	/*
5210 	 * First take lines from the frames after the current frame.  If
5211 	 * that is not enough, takes lines from frames above the current
5212 	 * frame.
5213 	 */
5214 	for (run = 0; run < 2; ++run)
5215 	{
5216 	    if (run == 0)
5217 		frp = curfrp->fr_next;	/* 1st run: start with next window */
5218 	    else
5219 		frp = curfrp->fr_prev;	/* 2nd run: start with prev window */
5220 	    while (frp != NULL && take != 0)
5221 	    {
5222 		h = frame_minheight(frp, NULL);
5223 		if (room_reserved > 0
5224 			&& frp->fr_win != NULL
5225 			&& frp->fr_win->w_p_wfh)
5226 		{
5227 		    if (room_reserved >= frp->fr_height)
5228 			room_reserved -= frp->fr_height;
5229 		    else
5230 		    {
5231 			if (frp->fr_height - room_reserved > take)
5232 			    room_reserved = frp->fr_height - take;
5233 			take -= frp->fr_height - room_reserved;
5234 			frame_new_height(frp, room_reserved, FALSE, FALSE);
5235 			room_reserved = 0;
5236 		    }
5237 		}
5238 		else
5239 		{
5240 		    if (frp->fr_height - take < h)
5241 		    {
5242 			take -= frp->fr_height - h;
5243 			frame_new_height(frp, h, FALSE, FALSE);
5244 		    }
5245 		    else
5246 		    {
5247 			frame_new_height(frp, frp->fr_height - take,
5248 								FALSE, FALSE);
5249 			take = 0;
5250 		    }
5251 		}
5252 		if (run == 0)
5253 		    frp = frp->fr_next;
5254 		else
5255 		    frp = frp->fr_prev;
5256 	    }
5257 	}
5258     }
5259 }
5260 
5261 /*
5262  * Set current window width and take care of repositioning other windows to
5263  * fit around it.
5264  */
5265     void
5266 win_setwidth(int width)
5267 {
5268     win_setwidth_win(width, curwin);
5269 }
5270 
5271     void
5272 win_setwidth_win(int width, win_T *wp)
5273 {
5274     /* Always keep current window at least one column wide, even when
5275      * 'winminwidth' is zero. */
5276     if (wp == curwin)
5277     {
5278 	if (width < p_wmw)
5279 	    width = p_wmw;
5280 	if (width == 0)
5281 	    width = 1;
5282     }
5283 
5284     frame_setwidth(wp->w_frame, width + wp->w_vsep_width);
5285 
5286     /* recompute the window positions */
5287     (void)win_comp_pos();
5288 
5289     redraw_all_later(NOT_VALID);
5290 }
5291 
5292 /*
5293  * Set the width of a frame to "width" and take care that all frames and
5294  * windows inside it are resized.  Also resize frames above and below if the
5295  * are in the same FR_ROW frame.
5296  *
5297  * Strategy is similar to frame_setheight().
5298  */
5299     static void
5300 frame_setwidth(frame_T *curfrp, int width)
5301 {
5302     int		room;		/* total number of lines available */
5303     int		take;		/* number of lines taken from other windows */
5304     int		run;
5305     frame_T	*frp;
5306     int		w;
5307     int		room_reserved;
5308 
5309     /* If the width already is the desired value, nothing to do. */
5310     if (curfrp->fr_width == width)
5311 	return;
5312 
5313     if (curfrp->fr_parent == NULL)
5314 	/* topframe: can't change width */
5315 	return;
5316 
5317     if (curfrp->fr_parent->fr_layout == FR_COL)
5318     {
5319 	/* Column of frames: Also need to resize frames above and below of
5320 	 * this one.  First check for the minimal width of these. */
5321 	w = frame_minwidth(curfrp->fr_parent, NULL);
5322 	if (width < w)
5323 	    width = w;
5324 	frame_setwidth(curfrp->fr_parent, width);
5325     }
5326     else
5327     {
5328 	/*
5329 	 * Row of frames: try to change only frames in this row.
5330 	 *
5331 	 * Do this twice:
5332 	 * 1: compute room available, if it's not enough try resizing the
5333 	 *    containing frame.
5334 	 * 2: compute the room available and adjust the width to it.
5335 	 */
5336 	for (run = 1; run <= 2; ++run)
5337 	{
5338 	    room = 0;
5339 	    room_reserved = 0;
5340 	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
5341 							   frp = frp->fr_next)
5342 	    {
5343 		if (frp != curfrp
5344 			&& frp->fr_win != NULL
5345 			&& frp->fr_win->w_p_wfw)
5346 		    room_reserved += frp->fr_width;
5347 		room += frp->fr_width;
5348 		if (frp != curfrp)
5349 		    room -= frame_minwidth(frp, NULL);
5350 	    }
5351 
5352 	    if (width <= room)
5353 		break;
5354 	    if (run == 2 || curfrp->fr_height >= ROWS_AVAIL)
5355 	    {
5356 		if (width > room)
5357 		    width = room;
5358 		break;
5359 	    }
5360 	    frame_setwidth(curfrp->fr_parent, width
5361 		 + frame_minwidth(curfrp->fr_parent, NOWIN) - (int)p_wmw - 1);
5362 	}
5363 
5364 	/*
5365 	 * Compute the number of lines we will take from others frames (can be
5366 	 * negative!).
5367 	 */
5368 	take = width - curfrp->fr_width;
5369 
5370 	/* If there is not enough room, also reduce the width of a window
5371 	 * with 'winfixwidth' set. */
5372 	if (width > room - room_reserved)
5373 	    room_reserved = room - width;
5374 	/* If there is only a 'winfixwidth' window and making the
5375 	 * window smaller, need to make the other window narrower. */
5376 	if (take < 0 && room - curfrp->fr_width < room_reserved)
5377 	    room_reserved = 0;
5378 
5379 	/*
5380 	 * set the current frame to the new width
5381 	 */
5382 	frame_new_width(curfrp, width, FALSE, FALSE);
5383 
5384 	/*
5385 	 * First take lines from the frames right of the current frame.  If
5386 	 * that is not enough, takes lines from frames left of the current
5387 	 * frame.
5388 	 */
5389 	for (run = 0; run < 2; ++run)
5390 	{
5391 	    if (run == 0)
5392 		frp = curfrp->fr_next;	/* 1st run: start with next window */
5393 	    else
5394 		frp = curfrp->fr_prev;	/* 2nd run: start with prev window */
5395 	    while (frp != NULL && take != 0)
5396 	    {
5397 		w = frame_minwidth(frp, NULL);
5398 		if (room_reserved > 0
5399 			&& frp->fr_win != NULL
5400 			&& frp->fr_win->w_p_wfw)
5401 		{
5402 		    if (room_reserved >= frp->fr_width)
5403 			room_reserved -= frp->fr_width;
5404 		    else
5405 		    {
5406 			if (frp->fr_width - room_reserved > take)
5407 			    room_reserved = frp->fr_width - take;
5408 			take -= frp->fr_width - room_reserved;
5409 			frame_new_width(frp, room_reserved, FALSE, FALSE);
5410 			room_reserved = 0;
5411 		    }
5412 		}
5413 		else
5414 		{
5415 		    if (frp->fr_width - take < w)
5416 		    {
5417 			take -= frp->fr_width - w;
5418 			frame_new_width(frp, w, FALSE, FALSE);
5419 		    }
5420 		    else
5421 		    {
5422 			frame_new_width(frp, frp->fr_width - take,
5423 								FALSE, FALSE);
5424 			take = 0;
5425 		    }
5426 		}
5427 		if (run == 0)
5428 		    frp = frp->fr_next;
5429 		else
5430 		    frp = frp->fr_prev;
5431 	    }
5432 	}
5433     }
5434 }
5435 
5436 /*
5437  * Check 'winminheight' for a valid value and reduce it if needed.
5438  */
5439     void
5440 win_setminheight(void)
5441 {
5442     int		room;
5443     int		needed;
5444     int		first = TRUE;
5445 
5446     // loop until there is a 'winminheight' that is possible
5447     while (p_wmh > 0)
5448     {
5449 	room = Rows - p_ch;
5450 	needed = frame_minheight(topframe, NULL);
5451 	if (room >= needed)
5452 	    break;
5453 	--p_wmh;
5454 	if (first)
5455 	{
5456 	    EMSG(_(e_noroom));
5457 	    first = FALSE;
5458 	}
5459     }
5460 }
5461 
5462 /*
5463  * Check 'winminwidth' for a valid value and reduce it if needed.
5464  */
5465     void
5466 win_setminwidth(void)
5467 {
5468     int		room;
5469     int		needed;
5470     int		first = TRUE;
5471 
5472     // loop until there is a 'winminheight' that is possible
5473     while (p_wmw > 0)
5474     {
5475 	room = Columns;
5476 	needed = frame_minwidth(topframe, NULL);
5477 	if (room >= needed)
5478 	    break;
5479 	--p_wmw;
5480 	if (first)
5481 	{
5482 	    EMSG(_(e_noroom));
5483 	    first = FALSE;
5484 	}
5485     }
5486 }
5487 
5488 #if defined(FEAT_MOUSE) || defined(PROTO)
5489 
5490 /*
5491  * Status line of dragwin is dragged "offset" lines down (negative is up).
5492  */
5493     void
5494 win_drag_status_line(win_T *dragwin, int offset)
5495 {
5496     frame_T	*curfr;
5497     frame_T	*fr;
5498     int		room;
5499     int		row;
5500     int		up;	/* if TRUE, drag status line up, otherwise down */
5501     int		n;
5502 
5503     fr = dragwin->w_frame;
5504     curfr = fr;
5505     if (fr != topframe)		/* more than one window */
5506     {
5507 	fr = fr->fr_parent;
5508 	/* When the parent frame is not a column of frames, its parent should
5509 	 * be. */
5510 	if (fr->fr_layout != FR_COL)
5511 	{
5512 	    curfr = fr;
5513 	    if (fr != topframe)	/* only a row of windows, may drag statusline */
5514 		fr = fr->fr_parent;
5515 	}
5516     }
5517 
5518     /* If this is the last frame in a column, may want to resize the parent
5519      * frame instead (go two up to skip a row of frames). */
5520     while (curfr != topframe && curfr->fr_next == NULL)
5521     {
5522 	if (fr != topframe)
5523 	    fr = fr->fr_parent;
5524 	curfr = fr;
5525 	if (fr != topframe)
5526 	    fr = fr->fr_parent;
5527     }
5528 
5529     if (offset < 0) /* drag up */
5530     {
5531 	up = TRUE;
5532 	offset = -offset;
5533 	/* sum up the room of the current frame and above it */
5534 	if (fr == curfr)
5535 	{
5536 	    /* only one window */
5537 	    room = fr->fr_height - frame_minheight(fr, NULL);
5538 	}
5539 	else
5540 	{
5541 	    room = 0;
5542 	    for (fr = fr->fr_child; ; fr = fr->fr_next)
5543 	    {
5544 		room += fr->fr_height - frame_minheight(fr, NULL);
5545 		if (fr == curfr)
5546 		    break;
5547 	    }
5548 	}
5549 	fr = curfr->fr_next;		/* put fr at frame that grows */
5550     }
5551     else    /* drag down */
5552     {
5553 	up = FALSE;
5554 	/*
5555 	 * Only dragging the last status line can reduce p_ch.
5556 	 */
5557 	room = Rows - cmdline_row;
5558 	if (curfr->fr_next == NULL)
5559 	    room -= 1;
5560 	else
5561 	    room -= p_ch;
5562 	if (room < 0)
5563 	    room = 0;
5564 	/* sum up the room of frames below of the current one */
5565 	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
5566 	    room += fr->fr_height - frame_minheight(fr, NULL);
5567 	fr = curfr;			/* put fr at window that grows */
5568     }
5569 
5570     if (room < offset)		/* Not enough room */
5571 	offset = room;		/* Move as far as we can */
5572     if (offset <= 0)
5573 	return;
5574 
5575     /*
5576      * Grow frame fr by "offset" lines.
5577      * Doesn't happen when dragging the last status line up.
5578      */
5579     if (fr != NULL)
5580 	frame_new_height(fr, fr->fr_height + offset, up, FALSE);
5581 
5582     if (up)
5583 	fr = curfr;		/* current frame gets smaller */
5584     else
5585 	fr = curfr->fr_next;	/* next frame gets smaller */
5586 
5587     /*
5588      * Now make the other frames smaller.
5589      */
5590     while (fr != NULL && offset > 0)
5591     {
5592 	n = frame_minheight(fr, NULL);
5593 	if (fr->fr_height - offset <= n)
5594 	{
5595 	    offset -= fr->fr_height - n;
5596 	    frame_new_height(fr, n, !up, FALSE);
5597 	}
5598 	else
5599 	{
5600 	    frame_new_height(fr, fr->fr_height - offset, !up, FALSE);
5601 	    break;
5602 	}
5603 	if (up)
5604 	    fr = fr->fr_prev;
5605 	else
5606 	    fr = fr->fr_next;
5607     }
5608     row = win_comp_pos();
5609     screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5610     cmdline_row = row;
5611     p_ch = Rows - cmdline_row;
5612     if (p_ch < 1)
5613 	p_ch = 1;
5614     curtab->tp_ch_used = p_ch;
5615     redraw_all_later(SOME_VALID);
5616     showmode();
5617 }
5618 
5619 /*
5620  * Separator line of dragwin is dragged "offset" lines right (negative is left).
5621  */
5622     void
5623 win_drag_vsep_line(win_T *dragwin, int offset)
5624 {
5625     frame_T	*curfr;
5626     frame_T	*fr;
5627     int		room;
5628     int		left;	/* if TRUE, drag separator line left, otherwise right */
5629     int		n;
5630 
5631     fr = dragwin->w_frame;
5632     if (fr == topframe)		/* only one window (cannot happen?) */
5633 	return;
5634     curfr = fr;
5635     fr = fr->fr_parent;
5636     /* When the parent frame is not a row of frames, its parent should be. */
5637     if (fr->fr_layout != FR_ROW)
5638     {
5639 	if (fr == topframe)	/* only a column of windows (cannot happen?) */
5640 	    return;
5641 	curfr = fr;
5642 	fr = fr->fr_parent;
5643     }
5644 
5645     /* If this is the last frame in a row, may want to resize a parent
5646      * frame instead. */
5647     while (curfr->fr_next == NULL)
5648     {
5649 	if (fr == topframe)
5650 	    break;
5651 	curfr = fr;
5652 	fr = fr->fr_parent;
5653 	if (fr != topframe)
5654 	{
5655 	    curfr = fr;
5656 	    fr = fr->fr_parent;
5657 	}
5658     }
5659 
5660     if (offset < 0) /* drag left */
5661     {
5662 	left = TRUE;
5663 	offset = -offset;
5664 	/* sum up the room of the current frame and left of it */
5665 	room = 0;
5666 	for (fr = fr->fr_child; ; fr = fr->fr_next)
5667 	{
5668 	    room += fr->fr_width - frame_minwidth(fr, NULL);
5669 	    if (fr == curfr)
5670 		break;
5671 	}
5672 	fr = curfr->fr_next;		/* put fr at frame that grows */
5673     }
5674     else    /* drag right */
5675     {
5676 	left = FALSE;
5677 	/* sum up the room of frames right of the current one */
5678 	room = 0;
5679 	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
5680 	    room += fr->fr_width - frame_minwidth(fr, NULL);
5681 	fr = curfr;			/* put fr at window that grows */
5682     }
5683 
5684     if (room < offset)		/* Not enough room */
5685 	offset = room;		/* Move as far as we can */
5686     if (offset <= 0)		/* No room at all, quit. */
5687 	return;
5688     if (fr == NULL)
5689 	return;			/* Safety check, should not happen. */
5690 
5691     /* grow frame fr by offset lines */
5692     frame_new_width(fr, fr->fr_width + offset, left, FALSE);
5693 
5694     /* shrink other frames: current and at the left or at the right */
5695     if (left)
5696 	fr = curfr;		/* current frame gets smaller */
5697     else
5698 	fr = curfr->fr_next;	/* next frame gets smaller */
5699 
5700     while (fr != NULL && offset > 0)
5701     {
5702 	n = frame_minwidth(fr, NULL);
5703 	if (fr->fr_width - offset <= n)
5704 	{
5705 	    offset -= fr->fr_width - n;
5706 	    frame_new_width(fr, n, !left, FALSE);
5707 	}
5708 	else
5709 	{
5710 	    frame_new_width(fr, fr->fr_width - offset, !left, FALSE);
5711 	    break;
5712 	}
5713 	if (left)
5714 	    fr = fr->fr_prev;
5715 	else
5716 	    fr = fr->fr_next;
5717     }
5718     (void)win_comp_pos();
5719     redraw_all_later(NOT_VALID);
5720 }
5721 #endif /* FEAT_MOUSE */
5722 
5723 #define FRACTION_MULT	16384L
5724 
5725 /*
5726  * Set wp->w_fraction for the current w_wrow and w_height.
5727  * Has no effect when the window is less than two lines.
5728  */
5729     void
5730 set_fraction(win_T *wp)
5731 {
5732     if (wp->w_height > 1)
5733 	wp->w_fraction = ((long)wp->w_wrow * FRACTION_MULT
5734 				    + wp->w_height / 2) / (long)wp->w_height;
5735 }
5736 
5737 /*
5738  * Set the height of a window.
5739  * "height" excludes any window toolbar.
5740  * This takes care of the things inside the window, not what happens to the
5741  * window position, the frame or to other windows.
5742  */
5743     void
5744 win_new_height(win_T *wp, int height)
5745 {
5746     int		prev_height = wp->w_height;
5747 
5748     /* Don't want a negative height.  Happens when splitting a tiny window.
5749      * Will equalize heights soon to fix it. */
5750     if (height < 0)
5751 	height = 0;
5752     if (wp->w_height == height)
5753 	return;	    /* nothing to do */
5754 
5755     if (wp->w_height > 0)
5756     {
5757 	if (wp == curwin)
5758 	    /* w_wrow needs to be valid. When setting 'laststatus' this may
5759 	     * call win_new_height() recursively. */
5760 	    validate_cursor();
5761 	if (wp->w_height != prev_height)
5762 	    return;  /* Recursive call already changed the size, bail out here
5763 			to avoid the following to mess things up. */
5764 	if (wp->w_wrow != wp->w_prev_fraction_row)
5765 	    set_fraction(wp);
5766     }
5767 
5768     wp->w_height = height;
5769     wp->w_skipcol = 0;
5770 
5771     /* There is no point in adjusting the scroll position when exiting.  Some
5772      * values might be invalid. */
5773     if (!exiting)
5774 	scroll_to_fraction(wp, prev_height);
5775 }
5776 
5777     void
5778 scroll_to_fraction(win_T *wp, int prev_height)
5779 {
5780     linenr_T	lnum;
5781     int		sline, line_size;
5782     int		height = wp->w_height;
5783 
5784     /* Don't change w_topline when height is zero.  Don't set w_topline when
5785      * 'scrollbind' is set and this isn't the current window. */
5786     if (height > 0 && (!wp->w_p_scb || wp == curwin))
5787     {
5788 	/*
5789 	 * Find a value for w_topline that shows the cursor at the same
5790 	 * relative position in the window as before (more or less).
5791 	 */
5792 	lnum = wp->w_cursor.lnum;
5793 	if (lnum < 1)		/* can happen when starting up */
5794 	    lnum = 1;
5795 	wp->w_wrow = ((long)wp->w_fraction * (long)height - 1L
5796 					 + FRACTION_MULT / 2) / FRACTION_MULT;
5797 	line_size = plines_win_col(wp, lnum, (long)(wp->w_cursor.col)) - 1;
5798 	sline = wp->w_wrow - line_size;
5799 
5800 	if (sline >= 0)
5801 	{
5802 	    /* Make sure the whole cursor line is visible, if possible. */
5803 	    int rows = plines_win(wp, lnum, FALSE);
5804 
5805 	    if (sline > wp->w_height - rows)
5806 	    {
5807 		sline = wp->w_height - rows;
5808 		wp->w_wrow -= rows - line_size;
5809 	    }
5810 	}
5811 
5812 	if (sline < 0)
5813 	{
5814 	    /*
5815 	     * Cursor line would go off top of screen if w_wrow was this high.
5816 	     * Make cursor line the first line in the window.  If not enough
5817 	     * room use w_skipcol;
5818 	     */
5819 	    wp->w_wrow = line_size;
5820 	    if (wp->w_wrow >= wp->w_height
5821 				       && (wp->w_width - win_col_off(wp)) > 0)
5822 	    {
5823 		wp->w_skipcol += wp->w_width - win_col_off(wp);
5824 		--wp->w_wrow;
5825 		while (wp->w_wrow >= wp->w_height)
5826 		{
5827 		    wp->w_skipcol += wp->w_width - win_col_off(wp)
5828 							   + win_col_off2(wp);
5829 		    --wp->w_wrow;
5830 		}
5831 	    }
5832 	    set_topline(wp, lnum);
5833 	}
5834 	else if (sline > 0)
5835 	{
5836 	    while (sline > 0 && lnum > 1)
5837 	    {
5838 #ifdef FEAT_FOLDING
5839 		hasFoldingWin(wp, lnum, &lnum, NULL, TRUE, NULL);
5840 		if (lnum == 1)
5841 		{
5842 		    /* first line in buffer is folded */
5843 		    line_size = 1;
5844 		    --sline;
5845 		    break;
5846 		}
5847 #endif
5848 		--lnum;
5849 #ifdef FEAT_DIFF
5850 		if (lnum == wp->w_topline)
5851 		    line_size = plines_win_nofill(wp, lnum, TRUE)
5852 							      + wp->w_topfill;
5853 		else
5854 #endif
5855 		    line_size = plines_win(wp, lnum, TRUE);
5856 		sline -= line_size;
5857 	    }
5858 
5859 	    if (sline < 0)
5860 	    {
5861 		/*
5862 		 * Line we want at top would go off top of screen.  Use next
5863 		 * line instead.
5864 		 */
5865 #ifdef FEAT_FOLDING
5866 		hasFoldingWin(wp, lnum, NULL, &lnum, TRUE, NULL);
5867 #endif
5868 		lnum++;
5869 		wp->w_wrow -= line_size + sline;
5870 	    }
5871 	    else if (sline > 0)
5872 	    {
5873 		/* First line of file reached, use that as topline. */
5874 		lnum = 1;
5875 		wp->w_wrow -= sline;
5876 	    }
5877 
5878 	    set_topline(wp, lnum);
5879 	}
5880     }
5881 
5882     if (wp == curwin)
5883     {
5884 	if (p_so)
5885 	    update_topline();
5886 	curs_columns(FALSE);	/* validate w_wrow */
5887     }
5888     if (prev_height > 0)
5889 	wp->w_prev_fraction_row = wp->w_wrow;
5890 
5891     win_comp_scroll(wp);
5892     redraw_win_later(wp, SOME_VALID);
5893     wp->w_redr_status = TRUE;
5894     invalidate_botline_win(wp);
5895 }
5896 
5897 /*
5898  * Set the width of a window.
5899  */
5900     void
5901 win_new_width(win_T *wp, int width)
5902 {
5903     wp->w_width = width;
5904     wp->w_lines_valid = 0;
5905     changed_line_abv_curs_win(wp);
5906     invalidate_botline_win(wp);
5907     if (wp == curwin)
5908     {
5909 	update_topline();
5910 	curs_columns(TRUE);	/* validate w_wrow */
5911     }
5912     redraw_win_later(wp, NOT_VALID);
5913     wp->w_redr_status = TRUE;
5914 }
5915 
5916     void
5917 win_comp_scroll(win_T *wp)
5918 {
5919     wp->w_p_scr = ((unsigned)wp->w_height >> 1);
5920     if (wp->w_p_scr == 0)
5921 	wp->w_p_scr = 1;
5922 }
5923 
5924 /*
5925  * command_height: called whenever p_ch has been changed
5926  */
5927     void
5928 command_height(void)
5929 {
5930     int		h;
5931     frame_T	*frp;
5932     int		old_p_ch = curtab->tp_ch_used;
5933 
5934     /* Use the value of p_ch that we remembered.  This is needed for when the
5935      * GUI starts up, we can't be sure in what order things happen.  And when
5936      * p_ch was changed in another tab page. */
5937     curtab->tp_ch_used = p_ch;
5938 
5939     /* Find bottom frame with width of screen. */
5940     frp = lastwin->w_frame;
5941     while (frp->fr_width != Columns && frp->fr_parent != NULL)
5942 	frp = frp->fr_parent;
5943 
5944     /* Avoid changing the height of a window with 'winfixheight' set. */
5945     while (frp->fr_prev != NULL && frp->fr_layout == FR_LEAF
5946 						      && frp->fr_win->w_p_wfh)
5947 	frp = frp->fr_prev;
5948 
5949     if (starting != NO_SCREEN)
5950     {
5951 	cmdline_row = Rows - p_ch;
5952 
5953 	if (p_ch > old_p_ch)		    /* p_ch got bigger */
5954 	{
5955 	    while (p_ch > old_p_ch)
5956 	    {
5957 		if (frp == NULL)
5958 		{
5959 		    EMSG(_(e_noroom));
5960 		    p_ch = old_p_ch;
5961 		    curtab->tp_ch_used = p_ch;
5962 		    cmdline_row = Rows - p_ch;
5963 		    break;
5964 		}
5965 		h = frp->fr_height - frame_minheight(frp, NULL);
5966 		if (h > p_ch - old_p_ch)
5967 		    h = p_ch - old_p_ch;
5968 		old_p_ch += h;
5969 		frame_add_height(frp, -h);
5970 		frp = frp->fr_prev;
5971 	    }
5972 
5973 	    /* Recompute window positions. */
5974 	    (void)win_comp_pos();
5975 
5976 	    /* clear the lines added to cmdline */
5977 	    if (full_screen)
5978 		screen_fill((int)(cmdline_row), (int)Rows, 0,
5979 						   (int)Columns, ' ', ' ', 0);
5980 	    msg_row = cmdline_row;
5981 	    redraw_cmdline = TRUE;
5982 	    return;
5983 	}
5984 
5985 	if (msg_row < cmdline_row)
5986 	    msg_row = cmdline_row;
5987 	redraw_cmdline = TRUE;
5988     }
5989     frame_add_height(frp, (int)(old_p_ch - p_ch));
5990 
5991     /* Recompute window positions. */
5992     if (frp != lastwin->w_frame)
5993 	(void)win_comp_pos();
5994 }
5995 
5996 /*
5997  * Resize frame "frp" to be "n" lines higher (negative for less high).
5998  * Also resize the frames it is contained in.
5999  */
6000     static void
6001 frame_add_height(frame_T *frp, int n)
6002 {
6003     frame_new_height(frp, frp->fr_height + n, FALSE, FALSE);
6004     for (;;)
6005     {
6006 	frp = frp->fr_parent;
6007 	if (frp == NULL)
6008 	    break;
6009 	frp->fr_height += n;
6010     }
6011 }
6012 
6013 /*
6014  * Add or remove a status line for the bottom window(s), according to the
6015  * value of 'laststatus'.
6016  */
6017     void
6018 last_status(
6019     int		morewin)	/* pretend there are two or more windows */
6020 {
6021     /* Don't make a difference between horizontal or vertical split. */
6022     last_status_rec(topframe, (p_ls == 2
6023 			  || (p_ls == 1 && (morewin || !ONE_WINDOW))));
6024 }
6025 
6026     static void
6027 last_status_rec(frame_T *fr, int statusline)
6028 {
6029     frame_T	*fp;
6030     win_T	*wp;
6031 
6032     if (fr->fr_layout == FR_LEAF)
6033     {
6034 	wp = fr->fr_win;
6035 	if (wp->w_status_height != 0 && !statusline)
6036 	{
6037 	    /* remove status line */
6038 	    win_new_height(wp, wp->w_height + 1);
6039 	    wp->w_status_height = 0;
6040 	    comp_col();
6041 	}
6042 	else if (wp->w_status_height == 0 && statusline)
6043 	{
6044 	    /* Find a frame to take a line from. */
6045 	    fp = fr;
6046 	    while (fp->fr_height <= frame_minheight(fp, NULL))
6047 	    {
6048 		if (fp == topframe)
6049 		{
6050 		    EMSG(_(e_noroom));
6051 		    return;
6052 		}
6053 		/* In a column of frames: go to frame above.  If already at
6054 		 * the top or in a row of frames: go to parent. */
6055 		if (fp->fr_parent->fr_layout == FR_COL && fp->fr_prev != NULL)
6056 		    fp = fp->fr_prev;
6057 		else
6058 		    fp = fp->fr_parent;
6059 	    }
6060 	    wp->w_status_height = 1;
6061 	    if (fp != fr)
6062 	    {
6063 		frame_new_height(fp, fp->fr_height - 1, FALSE, FALSE);
6064 		frame_fix_height(wp);
6065 		(void)win_comp_pos();
6066 	    }
6067 	    else
6068 		win_new_height(wp, wp->w_height - 1);
6069 	    comp_col();
6070 	    redraw_all_later(SOME_VALID);
6071 	}
6072     }
6073     else if (fr->fr_layout == FR_ROW)
6074     {
6075 	/* vertically split windows, set status line for each one */
6076 	for (fp = fr->fr_child; fp != NULL; fp = fp->fr_next)
6077 	    last_status_rec(fp, statusline);
6078     }
6079     else
6080     {
6081 	/* horizontally split window, set status line for last one */
6082 	for (fp = fr->fr_child; fp->fr_next != NULL; fp = fp->fr_next)
6083 	    ;
6084 	last_status_rec(fp, statusline);
6085     }
6086 }
6087 
6088 /*
6089  * Return the number of lines used by the tab page line.
6090  */
6091     int
6092 tabline_height(void)
6093 {
6094 #ifdef FEAT_GUI_TABLINE
6095     /* When the GUI has the tabline then this always returns zero. */
6096     if (gui_use_tabline())
6097 	return 0;
6098 #endif
6099     switch (p_stal)
6100     {
6101 	case 0: return 0;
6102 	case 1: return (first_tabpage->tp_next == NULL) ? 0 : 1;
6103     }
6104     return 1;
6105 }
6106 
6107 #if defined(FEAT_SEARCHPATH) || defined(PROTO)
6108 /*
6109  * Get the file name at the cursor.
6110  * If Visual mode is active, use the selected text if it's in one line.
6111  * Returns the name in allocated memory, NULL for failure.
6112  */
6113     char_u *
6114 grab_file_name(long count, linenr_T *file_lnum)
6115 {
6116     int options = FNAME_MESS|FNAME_EXP|FNAME_REL|FNAME_UNESC;
6117 
6118     if (VIsual_active)
6119     {
6120 	int	len;
6121 	char_u	*ptr;
6122 
6123 	if (get_visual_text(NULL, &ptr, &len) == FAIL)
6124 	    return NULL;
6125 	return find_file_name_in_path(ptr, len, options,
6126 						     count, curbuf->b_ffname);
6127     }
6128     return file_name_at_cursor(options | FNAME_HYP, count, file_lnum);
6129 }
6130 
6131 /*
6132  * Return the file name under or after the cursor.
6133  *
6134  * The 'path' option is searched if the file name is not absolute.
6135  * The string returned has been alloc'ed and should be freed by the caller.
6136  * NULL is returned if the file name or file is not found.
6137  *
6138  * options:
6139  * FNAME_MESS	    give error messages
6140  * FNAME_EXP	    expand to path
6141  * FNAME_HYP	    check for hypertext link
6142  * FNAME_INCL	    apply "includeexpr"
6143  */
6144     char_u *
6145 file_name_at_cursor(int options, long count, linenr_T *file_lnum)
6146 {
6147     return file_name_in_line(ml_get_curline(),
6148 		      curwin->w_cursor.col, options, count, curbuf->b_ffname,
6149 		      file_lnum);
6150 }
6151 
6152 /*
6153  * Return the name of the file under or after ptr[col].
6154  * Otherwise like file_name_at_cursor().
6155  */
6156     char_u *
6157 file_name_in_line(
6158     char_u	*line,
6159     int		col,
6160     int		options,
6161     long	count,
6162     char_u	*rel_fname,	/* file we are searching relative to */
6163     linenr_T	*file_lnum)	/* line number after the file name */
6164 {
6165     char_u	*ptr;
6166     int		len;
6167     int		in_type = TRUE;
6168     int		is_url = FALSE;
6169 
6170     /*
6171      * search forward for what could be the start of a file name
6172      */
6173     ptr = line + col;
6174     while (*ptr != NUL && !vim_isfilec(*ptr))
6175 	MB_PTR_ADV(ptr);
6176     if (*ptr == NUL)		/* nothing found */
6177     {
6178 	if (options & FNAME_MESS)
6179 	    EMSG(_("E446: No file name under cursor"));
6180 	return NULL;
6181     }
6182 
6183     /*
6184      * Search backward for first char of the file name.
6185      * Go one char back to ":" before "//" even when ':' is not in 'isfname'.
6186      */
6187     while (ptr > line)
6188     {
6189 #ifdef FEAT_MBYTE
6190 	if (has_mbyte && (len = (*mb_head_off)(line, ptr - 1)) > 0)
6191 	    ptr -= len + 1;
6192 	else
6193 #endif
6194 	if (vim_isfilec(ptr[-1])
6195 		|| ((options & FNAME_HYP) && path_is_url(ptr - 1)))
6196 	    --ptr;
6197 	else
6198 	    break;
6199     }
6200 
6201     /*
6202      * Search forward for the last char of the file name.
6203      * Also allow "://" when ':' is not in 'isfname'.
6204      */
6205     len = 0;
6206     while (vim_isfilec(ptr[len]) || (ptr[len] == '\\' && ptr[len + 1] == ' ')
6207 			 || ((options & FNAME_HYP) && path_is_url(ptr + len))
6208 			 || (is_url && vim_strchr((char_u *)"?&=", ptr[len]) != NULL))
6209     {
6210 	/* After type:// we also include ?, & and = as valid characters, so that
6211 	 * http://google.com?q=this&that=ok works. */
6212 	if ((ptr[len] >= 'A' && ptr[len] <= 'Z') || (ptr[len] >= 'a' && ptr[len] <= 'z'))
6213 	{
6214 	    if (in_type && path_is_url(ptr + len + 1))
6215 		is_url = TRUE;
6216 	}
6217 	else
6218 	    in_type = FALSE;
6219 
6220 	if (ptr[len] == '\\')
6221 	    /* Skip over the "\" in "\ ". */
6222 	    ++len;
6223 #ifdef FEAT_MBYTE
6224 	if (has_mbyte)
6225 	    len += (*mb_ptr2len)(ptr + len);
6226 	else
6227 #endif
6228 	    ++len;
6229     }
6230 
6231     /*
6232      * If there is trailing punctuation, remove it.
6233      * But don't remove "..", could be a directory name.
6234      */
6235     if (len > 2 && vim_strchr((char_u *)".,:;!", ptr[len - 1]) != NULL
6236 						       && ptr[len - 2] != '.')
6237 	--len;
6238 
6239     if (file_lnum != NULL)
6240     {
6241 	char_u *p;
6242 
6243 	/* Get the number after the file name and a separator character */
6244 	p = ptr + len;
6245 	p = skipwhite(p);
6246 	if (*p != NUL)
6247 	{
6248 	    if (!isdigit(*p))
6249 		++p;		    /* skip the separator */
6250 	    p = skipwhite(p);
6251 	    if (isdigit(*p))
6252 		*file_lnum = (int)getdigits(&p);
6253 	}
6254     }
6255 
6256     return find_file_name_in_path(ptr, len, options, count, rel_fname);
6257 }
6258 
6259 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6260     static char_u *
6261 eval_includeexpr(char_u *ptr, int len)
6262 {
6263     char_u	*res;
6264 
6265     set_vim_var_string(VV_FNAME, ptr, len);
6266     res = eval_to_string_safe(curbuf->b_p_inex, NULL,
6267 		      was_set_insecurely((char_u *)"includeexpr", OPT_LOCAL));
6268     set_vim_var_string(VV_FNAME, NULL, 0);
6269     return res;
6270 }
6271 #endif
6272 
6273 /*
6274  * Return the name of the file ptr[len] in 'path'.
6275  * Otherwise like file_name_at_cursor().
6276  */
6277     char_u *
6278 find_file_name_in_path(
6279     char_u	*ptr,
6280     int		len,
6281     int		options,
6282     long	count,
6283     char_u	*rel_fname)	/* file we are searching relative to */
6284 {
6285     char_u	*file_name;
6286     int		c;
6287 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6288     char_u	*tofree = NULL;
6289 
6290     if ((options & FNAME_INCL) && *curbuf->b_p_inex != NUL)
6291     {
6292 	tofree = eval_includeexpr(ptr, len);
6293 	if (tofree != NULL)
6294 	{
6295 	    ptr = tofree;
6296 	    len = (int)STRLEN(ptr);
6297 	}
6298     }
6299 # endif
6300 
6301     if (options & FNAME_EXP)
6302     {
6303 	file_name = find_file_in_path(ptr, len, options & ~FNAME_MESS,
6304 							     TRUE, rel_fname);
6305 
6306 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6307 	/*
6308 	 * If the file could not be found in a normal way, try applying
6309 	 * 'includeexpr' (unless done already).
6310 	 */
6311 	if (file_name == NULL
6312 		&& !(options & FNAME_INCL) && *curbuf->b_p_inex != NUL)
6313 	{
6314 	    tofree = eval_includeexpr(ptr, len);
6315 	    if (tofree != NULL)
6316 	    {
6317 		ptr = tofree;
6318 		len = (int)STRLEN(ptr);
6319 		file_name = find_file_in_path(ptr, len, options & ~FNAME_MESS,
6320 							     TRUE, rel_fname);
6321 	    }
6322 	}
6323 # endif
6324 	if (file_name == NULL && (options & FNAME_MESS))
6325 	{
6326 	    c = ptr[len];
6327 	    ptr[len] = NUL;
6328 	    EMSG2(_("E447: Can't find file \"%s\" in path"), ptr);
6329 	    ptr[len] = c;
6330 	}
6331 
6332 	/* Repeat finding the file "count" times.  This matters when it
6333 	 * appears several times in the path. */
6334 	while (file_name != NULL && --count > 0)
6335 	{
6336 	    vim_free(file_name);
6337 	    file_name = find_file_in_path(ptr, len, options, FALSE, rel_fname);
6338 	}
6339     }
6340     else
6341 	file_name = vim_strnsave(ptr, len);
6342 
6343 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6344     vim_free(tofree);
6345 # endif
6346 
6347     return file_name;
6348 }
6349 #endif /* FEAT_SEARCHPATH */
6350 
6351 /*
6352  * Check if the "://" of a URL is at the pointer, return URL_SLASH.
6353  * Also check for ":\\", which MS Internet Explorer accepts, return
6354  * URL_BACKSLASH.
6355  */
6356     static int
6357 path_is_url(char_u *p)
6358 {
6359     if (STRNCMP(p, "://", (size_t)3) == 0)
6360 	return URL_SLASH;
6361     else if (STRNCMP(p, ":\\\\", (size_t)3) == 0)
6362 	return URL_BACKSLASH;
6363     return 0;
6364 }
6365 
6366 /*
6367  * Check if "fname" starts with "name://".  Return URL_SLASH if it does.
6368  * Return URL_BACKSLASH for "name:\\".
6369  * Return zero otherwise.
6370  */
6371     int
6372 path_with_url(char_u *fname)
6373 {
6374     char_u *p;
6375 
6376     for (p = fname; isalpha(*p); ++p)
6377 	;
6378     return path_is_url(p);
6379 }
6380 
6381 /*
6382  * Return TRUE if "name" is a full (absolute) path name or URL.
6383  */
6384     int
6385 vim_isAbsName(char_u *name)
6386 {
6387     return (path_with_url(name) != 0 || mch_isFullName(name));
6388 }
6389 
6390 /*
6391  * Get absolute file name into buffer "buf[len]".
6392  *
6393  * return FAIL for failure, OK otherwise
6394  */
6395     int
6396 vim_FullName(
6397     char_u	*fname,
6398     char_u	*buf,
6399     int		len,
6400     int		force)	    /* force expansion even when already absolute */
6401 {
6402     int		retval = OK;
6403     int		url;
6404 
6405     *buf = NUL;
6406     if (fname == NULL)
6407 	return FAIL;
6408 
6409     url = path_with_url(fname);
6410     if (!url)
6411 	retval = mch_FullName(fname, buf, len, force);
6412     if (url || retval == FAIL)
6413     {
6414 	/* something failed; use the file name (truncate when too long) */
6415 	vim_strncpy(buf, fname, len - 1);
6416     }
6417 #if defined(MSWIN)
6418     slash_adjust(buf);
6419 #endif
6420     return retval;
6421 }
6422 
6423 /*
6424  * Return the minimal number of rows that is needed on the screen to display
6425  * the current number of windows.
6426  */
6427     int
6428 min_rows(void)
6429 {
6430     int		total;
6431     tabpage_T	*tp;
6432     int		n;
6433 
6434     if (firstwin == NULL)	/* not initialized yet */
6435 	return MIN_LINES;
6436 
6437     total = 0;
6438     FOR_ALL_TABPAGES(tp)
6439     {
6440 	n = frame_minheight(tp->tp_topframe, NULL);
6441 	if (total < n)
6442 	    total = n;
6443     }
6444     total += tabline_height();
6445     total += 1;		/* count the room for the command line */
6446     return total;
6447 }
6448 
6449 /*
6450  * Return TRUE if there is only one window (in the current tab page), not
6451  * counting a help or preview window, unless it is the current window.
6452  * Does not count "aucmd_win".
6453  */
6454     int
6455 only_one_window(void)
6456 {
6457     int		count = 0;
6458     win_T	*wp;
6459 
6460     /* If there is another tab page there always is another window. */
6461     if (first_tabpage->tp_next != NULL)
6462 	return FALSE;
6463 
6464     FOR_ALL_WINDOWS(wp)
6465 	if (wp->w_buffer != NULL
6466 		&& (!((bt_help(wp->w_buffer) && !bt_help(curbuf))
6467 # ifdef FEAT_QUICKFIX
6468 		    || wp->w_p_pvw
6469 # endif
6470 	     ) || wp == curwin) && wp != aucmd_win)
6471 	    ++count;
6472     return (count <= 1);
6473 }
6474 
6475 /*
6476  * Correct the cursor line number in other windows.  Used after changing the
6477  * current buffer, and before applying autocommands.
6478  * When "do_curwin" is TRUE, also check current window.
6479  */
6480     void
6481 check_lnums(int do_curwin)
6482 {
6483     win_T	*wp;
6484     tabpage_T	*tp;
6485 
6486     FOR_ALL_TAB_WINDOWS(tp, wp)
6487 	if ((do_curwin || wp != curwin) && wp->w_buffer == curbuf)
6488 	{
6489 	    if (wp->w_cursor.lnum > curbuf->b_ml.ml_line_count)
6490 		wp->w_cursor.lnum = curbuf->b_ml.ml_line_count;
6491 	    if (wp->w_topline > curbuf->b_ml.ml_line_count)
6492 		wp->w_topline = curbuf->b_ml.ml_line_count;
6493 	}
6494 }
6495 
6496 /*
6497  * A snapshot of the window sizes, to restore them after closing the help
6498  * window.
6499  * Only these fields are used:
6500  * fr_layout
6501  * fr_width
6502  * fr_height
6503  * fr_next
6504  * fr_child
6505  * fr_win (only valid for the old curwin, NULL otherwise)
6506  */
6507 
6508 /*
6509  * Create a snapshot of the current frame sizes.
6510  */
6511     void
6512 make_snapshot(int idx)
6513 {
6514     clear_snapshot(curtab, idx);
6515     make_snapshot_rec(topframe, &curtab->tp_snapshot[idx]);
6516 }
6517 
6518     static void
6519 make_snapshot_rec(frame_T *fr, frame_T **frp)
6520 {
6521     *frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
6522     if (*frp == NULL)
6523 	return;
6524     (*frp)->fr_layout = fr->fr_layout;
6525     (*frp)->fr_width = fr->fr_width;
6526     (*frp)->fr_height = fr->fr_height;
6527     if (fr->fr_next != NULL)
6528 	make_snapshot_rec(fr->fr_next, &((*frp)->fr_next));
6529     if (fr->fr_child != NULL)
6530 	make_snapshot_rec(fr->fr_child, &((*frp)->fr_child));
6531     if (fr->fr_layout == FR_LEAF && fr->fr_win == curwin)
6532 	(*frp)->fr_win = curwin;
6533 }
6534 
6535 /*
6536  * Remove any existing snapshot.
6537  */
6538     static void
6539 clear_snapshot(tabpage_T *tp, int idx)
6540 {
6541     clear_snapshot_rec(tp->tp_snapshot[idx]);
6542     tp->tp_snapshot[idx] = NULL;
6543 }
6544 
6545     static void
6546 clear_snapshot_rec(frame_T *fr)
6547 {
6548     if (fr != NULL)
6549     {
6550 	clear_snapshot_rec(fr->fr_next);
6551 	clear_snapshot_rec(fr->fr_child);
6552 	vim_free(fr);
6553     }
6554 }
6555 
6556 /*
6557  * Restore a previously created snapshot, if there is any.
6558  * This is only done if the screen size didn't change and the window layout is
6559  * still the same.
6560  */
6561     void
6562 restore_snapshot(
6563     int		idx,
6564     int		close_curwin)	    /* closing current window */
6565 {
6566     win_T	*wp;
6567 
6568     if (curtab->tp_snapshot[idx] != NULL
6569 	    && curtab->tp_snapshot[idx]->fr_width == topframe->fr_width
6570 	    && curtab->tp_snapshot[idx]->fr_height == topframe->fr_height
6571 	    && check_snapshot_rec(curtab->tp_snapshot[idx], topframe) == OK)
6572     {
6573 	wp = restore_snapshot_rec(curtab->tp_snapshot[idx], topframe);
6574 	win_comp_pos();
6575 	if (wp != NULL && close_curwin)
6576 	    win_goto(wp);
6577 	redraw_all_later(CLEAR);
6578     }
6579     clear_snapshot(curtab, idx);
6580 }
6581 
6582 /*
6583  * Check if frames "sn" and "fr" have the same layout, same following frames
6584  * and same children.  And the window pointer is valid.
6585  */
6586     static int
6587 check_snapshot_rec(frame_T *sn, frame_T *fr)
6588 {
6589     if (sn->fr_layout != fr->fr_layout
6590 	    || (sn->fr_next == NULL) != (fr->fr_next == NULL)
6591 	    || (sn->fr_child == NULL) != (fr->fr_child == NULL)
6592 	    || (sn->fr_next != NULL
6593 		&& check_snapshot_rec(sn->fr_next, fr->fr_next) == FAIL)
6594 	    || (sn->fr_child != NULL
6595 		&& check_snapshot_rec(sn->fr_child, fr->fr_child) == FAIL)
6596 	    || (sn->fr_win != NULL && !win_valid(sn->fr_win)))
6597 	return FAIL;
6598     return OK;
6599 }
6600 
6601 /*
6602  * Copy the size of snapshot frame "sn" to frame "fr".  Do the same for all
6603  * following frames and children.
6604  * Returns a pointer to the old current window, or NULL.
6605  */
6606     static win_T *
6607 restore_snapshot_rec(frame_T *sn, frame_T *fr)
6608 {
6609     win_T	*wp = NULL;
6610     win_T	*wp2;
6611 
6612     fr->fr_height = sn->fr_height;
6613     fr->fr_width = sn->fr_width;
6614     if (fr->fr_layout == FR_LEAF)
6615     {
6616 	frame_new_height(fr, fr->fr_height, FALSE, FALSE);
6617 	frame_new_width(fr, fr->fr_width, FALSE, FALSE);
6618 	wp = sn->fr_win;
6619     }
6620     if (sn->fr_next != NULL)
6621     {
6622 	wp2 = restore_snapshot_rec(sn->fr_next, fr->fr_next);
6623 	if (wp2 != NULL)
6624 	    wp = wp2;
6625     }
6626     if (sn->fr_child != NULL)
6627     {
6628 	wp2 = restore_snapshot_rec(sn->fr_child, fr->fr_child);
6629 	if (wp2 != NULL)
6630 	    wp = wp2;
6631     }
6632     return wp;
6633 }
6634 
6635 #if defined(FEAT_EVAL) || defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) \
6636 	|| defined(PROTO)
6637 /*
6638  * Set "win" to be the curwin and "tp" to be the current tab page.
6639  * restore_win() MUST be called to undo, also when FAIL is returned.
6640  * No autocommands will be executed until restore_win() is called.
6641  * When "no_display" is TRUE the display won't be affected, no redraw is
6642  * triggered, another tabpage access is limited.
6643  * Returns FAIL if switching to "win" failed.
6644  */
6645     int
6646 switch_win(
6647     win_T	**save_curwin,
6648     tabpage_T	**save_curtab,
6649     win_T	*win,
6650     tabpage_T	*tp,
6651     int		no_display)
6652 {
6653     block_autocmds();
6654     *save_curwin = curwin;
6655     if (tp != NULL)
6656     {
6657 	*save_curtab = curtab;
6658 	if (no_display)
6659 	{
6660 	    curtab->tp_firstwin = firstwin;
6661 	    curtab->tp_lastwin = lastwin;
6662 	    curtab = tp;
6663 	    firstwin = curtab->tp_firstwin;
6664 	    lastwin = curtab->tp_lastwin;
6665 	}
6666 	else
6667 	    goto_tabpage_tp(tp, FALSE, FALSE);
6668     }
6669     if (!win_valid(win))
6670 	return FAIL;
6671     curwin = win;
6672     curbuf = curwin->w_buffer;
6673     return OK;
6674 }
6675 
6676 /*
6677  * Restore current tabpage and window saved by switch_win(), if still valid.
6678  * When "no_display" is TRUE the display won't be affected, no redraw is
6679  * triggered.
6680  */
6681     void
6682 restore_win(
6683     win_T	*save_curwin UNUSED,
6684     tabpage_T	*save_curtab UNUSED,
6685     int		no_display UNUSED)
6686 {
6687     if (save_curtab != NULL && valid_tabpage(save_curtab))
6688     {
6689 	if (no_display)
6690 	{
6691 	    curtab->tp_firstwin = firstwin;
6692 	    curtab->tp_lastwin = lastwin;
6693 	    curtab = save_curtab;
6694 	    firstwin = curtab->tp_firstwin;
6695 	    lastwin = curtab->tp_lastwin;
6696 	}
6697 	else
6698 	    goto_tabpage_tp(save_curtab, FALSE, FALSE);
6699     }
6700     if (win_valid(save_curwin))
6701     {
6702 	curwin = save_curwin;
6703 	curbuf = curwin->w_buffer;
6704     }
6705     unblock_autocmds();
6706 }
6707 
6708 /*
6709  * Make "buf" the current buffer.  restore_buffer() MUST be called to undo.
6710  * No autocommands will be executed.  Use aucmd_prepbuf() if there are any.
6711  */
6712     void
6713 switch_buffer(bufref_T *save_curbuf, buf_T *buf)
6714 {
6715     block_autocmds();
6716     set_bufref(save_curbuf, curbuf);
6717     --curbuf->b_nwindows;
6718     curbuf = buf;
6719     curwin->w_buffer = buf;
6720     ++curbuf->b_nwindows;
6721 }
6722 
6723 /*
6724  * Restore the current buffer after using switch_buffer().
6725  */
6726     void
6727 restore_buffer(bufref_T *save_curbuf)
6728 {
6729     unblock_autocmds();
6730     /* Check for valid buffer, just in case. */
6731     if (bufref_valid(save_curbuf))
6732     {
6733 	--curbuf->b_nwindows;
6734 	curwin->w_buffer = save_curbuf->br_buf;
6735 	curbuf = save_curbuf->br_buf;
6736 	++curbuf->b_nwindows;
6737     }
6738 }
6739 #endif
6740 
6741 #if defined(FEAT_GUI) || defined(PROTO)
6742 /*
6743  * Return TRUE if there is any vertically split window.
6744  */
6745     int
6746 win_hasvertsplit(void)
6747 {
6748     frame_T	*fr;
6749 
6750     if (topframe->fr_layout == FR_ROW)
6751 	return TRUE;
6752 
6753     if (topframe->fr_layout == FR_COL)
6754 	for (fr = topframe->fr_child; fr != NULL; fr = fr->fr_next)
6755 	    if (fr->fr_layout == FR_ROW)
6756 		return TRUE;
6757 
6758     return FALSE;
6759 }
6760 #endif
6761 
6762 #if defined(FEAT_SEARCH_EXTRA) || defined(PROTO)
6763 /*
6764  * Add match to the match list of window 'wp'.  The pattern 'pat' will be
6765  * highlighted with the group 'grp' with priority 'prio'.
6766  * Optionally, a desired ID 'id' can be specified (greater than or equal to 1).
6767  * If no particular ID is desired, -1 must be specified for 'id'.
6768  * Return ID of added match, -1 on failure.
6769  */
6770     int
6771 match_add(
6772     win_T	*wp,
6773     char_u	*grp,
6774     char_u	*pat,
6775     int		prio,
6776     int		id,
6777     list_T	*pos_list,
6778     char_u      *conceal_char UNUSED) /* pointer to conceal replacement char */
6779 {
6780     matchitem_T	*cur;
6781     matchitem_T	*prev;
6782     matchitem_T	*m;
6783     int		hlg_id;
6784     regprog_T	*regprog = NULL;
6785     int		rtype = SOME_VALID;
6786 
6787     if (*grp == NUL || (pat != NULL && *pat == NUL))
6788 	return -1;
6789     if (id < -1 || id == 0)
6790     {
6791 	EMSGN(_("E799: Invalid ID: %ld (must be greater than or equal to 1)"), id);
6792 	return -1;
6793     }
6794     if (id != -1)
6795     {
6796 	cur = wp->w_match_head;
6797 	while (cur != NULL)
6798 	{
6799 	    if (cur->id == id)
6800 	    {
6801 		EMSGN(_("E801: ID already taken: %ld"), id);
6802 		return -1;
6803 	    }
6804 	    cur = cur->next;
6805 	}
6806     }
6807     if ((hlg_id = syn_namen2id(grp, (int)STRLEN(grp))) == 0)
6808     {
6809 	EMSG2(_(e_nogroup), grp);
6810 	return -1;
6811     }
6812     if (pat != NULL && (regprog = vim_regcomp(pat, RE_MAGIC)) == NULL)
6813     {
6814 	EMSG2(_(e_invarg2), pat);
6815 	return -1;
6816     }
6817 
6818     /* Find available match ID. */
6819     while (id == -1)
6820     {
6821 	cur = wp->w_match_head;
6822 	while (cur != NULL && cur->id != wp->w_next_match_id)
6823 	    cur = cur->next;
6824 	if (cur == NULL)
6825 	    id = wp->w_next_match_id;
6826 	wp->w_next_match_id++;
6827     }
6828 
6829     /* Build new match. */
6830     m = (matchitem_T *)alloc_clear(sizeof(matchitem_T));
6831     m->id = id;
6832     m->priority = prio;
6833     m->pattern = pat == NULL ? NULL : vim_strsave(pat);
6834     m->hlg_id = hlg_id;
6835     m->match.regprog = regprog;
6836     m->match.rmm_ic = FALSE;
6837     m->match.rmm_maxcol = 0;
6838 # if defined(FEAT_CONCEAL) && defined(FEAT_MBYTE)
6839     m->conceal_char = 0;
6840     if (conceal_char != NULL)
6841 	m->conceal_char = (*mb_ptr2char)(conceal_char);
6842 # endif
6843 
6844     /* Set up position matches */
6845     if (pos_list != NULL)
6846     {
6847 	linenr_T	toplnum = 0;
6848 	linenr_T	botlnum = 0;
6849 	listitem_T	*li;
6850 	int		i;
6851 
6852 	for (i = 0, li = pos_list->lv_first; li != NULL && i < MAXPOSMATCH;
6853 							i++, li = li->li_next)
6854 	{
6855 	    linenr_T	lnum = 0;
6856 	    colnr_T	col = 0;
6857 	    int		len = 1;
6858 	    list_T	*subl;
6859 	    listitem_T	*subli;
6860 	    int		error = FALSE;
6861 
6862 	    if (li->li_tv.v_type == VAR_LIST)
6863 	    {
6864 		subl = li->li_tv.vval.v_list;
6865 		if (subl == NULL)
6866 		    goto fail;
6867 		subli = subl->lv_first;
6868 		if (subli == NULL)
6869 		    goto fail;
6870 		lnum = get_tv_number_chk(&subli->li_tv, &error);
6871 		if (error == TRUE)
6872 		    goto fail;
6873 		if (lnum == 0)
6874 		{
6875 		    --i;
6876 		    continue;
6877 		}
6878 		m->pos.pos[i].lnum = lnum;
6879 		subli = subli->li_next;
6880 		if (subli != NULL)
6881 		{
6882 		    col = get_tv_number_chk(&subli->li_tv, &error);
6883 		    if (error == TRUE)
6884 			goto fail;
6885 		    subli = subli->li_next;
6886 		    if (subli != NULL)
6887 		    {
6888 			len = get_tv_number_chk(&subli->li_tv, &error);
6889 			if (error == TRUE)
6890 			    goto fail;
6891 		    }
6892 		}
6893 		m->pos.pos[i].col = col;
6894 		m->pos.pos[i].len = len;
6895 	    }
6896 	    else if (li->li_tv.v_type == VAR_NUMBER)
6897 	    {
6898 		if (li->li_tv.vval.v_number == 0)
6899 		{
6900 		    --i;
6901 		    continue;
6902 		}
6903 		m->pos.pos[i].lnum = li->li_tv.vval.v_number;
6904 		m->pos.pos[i].col = 0;
6905 		m->pos.pos[i].len = 0;
6906 	    }
6907 	    else
6908 	    {
6909 		EMSG(_("List or number required"));
6910 		goto fail;
6911 	    }
6912 	    if (toplnum == 0 || lnum < toplnum)
6913 		toplnum = lnum;
6914 	    if (botlnum == 0 || lnum >= botlnum)
6915 		botlnum = lnum + 1;
6916 	}
6917 
6918 	/* Calculate top and bottom lines for redrawing area */
6919 	if (toplnum != 0)
6920 	{
6921 	    if (wp->w_buffer->b_mod_set)
6922 	    {
6923 		if (wp->w_buffer->b_mod_top > toplnum)
6924 		    wp->w_buffer->b_mod_top = toplnum;
6925 		if (wp->w_buffer->b_mod_bot < botlnum)
6926 		    wp->w_buffer->b_mod_bot = botlnum;
6927 	    }
6928 	    else
6929 	    {
6930 		wp->w_buffer->b_mod_set = TRUE;
6931 		wp->w_buffer->b_mod_top = toplnum;
6932 		wp->w_buffer->b_mod_bot = botlnum;
6933 		wp->w_buffer->b_mod_xlines = 0;
6934 	    }
6935 	    m->pos.toplnum = toplnum;
6936 	    m->pos.botlnum = botlnum;
6937 	    rtype = VALID;
6938 	}
6939     }
6940 
6941     /* Insert new match.  The match list is in ascending order with regard to
6942      * the match priorities. */
6943     cur = wp->w_match_head;
6944     prev = cur;
6945     while (cur != NULL && prio >= cur->priority)
6946     {
6947 	prev = cur;
6948 	cur = cur->next;
6949     }
6950     if (cur == prev)
6951 	wp->w_match_head = m;
6952     else
6953 	prev->next = m;
6954     m->next = cur;
6955 
6956     redraw_later(rtype);
6957     return id;
6958 
6959 fail:
6960     vim_free(m);
6961     return -1;
6962 }
6963 
6964 /*
6965  * Delete match with ID 'id' in the match list of window 'wp'.
6966  * Print error messages if 'perr' is TRUE.
6967  */
6968     int
6969 match_delete(win_T *wp, int id, int perr)
6970 {
6971     matchitem_T	*cur = wp->w_match_head;
6972     matchitem_T	*prev = cur;
6973     int		rtype = SOME_VALID;
6974 
6975     if (id < 1)
6976     {
6977 	if (perr == TRUE)
6978 	    EMSGN(_("E802: Invalid ID: %ld (must be greater than or equal to 1)"),
6979 									  id);
6980 	return -1;
6981     }
6982     while (cur != NULL && cur->id != id)
6983     {
6984 	prev = cur;
6985 	cur = cur->next;
6986     }
6987     if (cur == NULL)
6988     {
6989 	if (perr == TRUE)
6990 	    EMSGN(_("E803: ID not found: %ld"), id);
6991 	return -1;
6992     }
6993     if (cur == prev)
6994 	wp->w_match_head = cur->next;
6995     else
6996 	prev->next = cur->next;
6997     vim_regfree(cur->match.regprog);
6998     vim_free(cur->pattern);
6999     if (cur->pos.toplnum != 0)
7000     {
7001 	if (wp->w_buffer->b_mod_set)
7002 	{
7003 	    if (wp->w_buffer->b_mod_top > cur->pos.toplnum)
7004 		wp->w_buffer->b_mod_top = cur->pos.toplnum;
7005 	    if (wp->w_buffer->b_mod_bot < cur->pos.botlnum)
7006 		wp->w_buffer->b_mod_bot = cur->pos.botlnum;
7007 	}
7008 	else
7009 	{
7010 	    wp->w_buffer->b_mod_set = TRUE;
7011 	    wp->w_buffer->b_mod_top = cur->pos.toplnum;
7012 	    wp->w_buffer->b_mod_bot = cur->pos.botlnum;
7013 	    wp->w_buffer->b_mod_xlines = 0;
7014 	}
7015 	rtype = VALID;
7016     }
7017     vim_free(cur);
7018     redraw_later(rtype);
7019     return 0;
7020 }
7021 
7022 /*
7023  * Delete all matches in the match list of window 'wp'.
7024  */
7025     void
7026 clear_matches(win_T *wp)
7027 {
7028     matchitem_T *m;
7029 
7030     while (wp->w_match_head != NULL)
7031     {
7032 	m = wp->w_match_head->next;
7033 	vim_regfree(wp->w_match_head->match.regprog);
7034 	vim_free(wp->w_match_head->pattern);
7035 	vim_free(wp->w_match_head);
7036 	wp->w_match_head = m;
7037     }
7038     redraw_later(SOME_VALID);
7039 }
7040 
7041 /*
7042  * Get match from ID 'id' in window 'wp'.
7043  * Return NULL if match not found.
7044  */
7045     matchitem_T *
7046 get_match(win_T *wp, int id)
7047 {
7048     matchitem_T *cur = wp->w_match_head;
7049 
7050     while (cur != NULL && cur->id != id)
7051 	cur = cur->next;
7052     return cur;
7053 }
7054 #endif
7055 
7056 #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) || defined(PROTO)
7057     int
7058 get_win_number(win_T *wp, win_T *first_win)
7059 {
7060     int		i = 1;
7061     win_T	*w;
7062 
7063     for (w = first_win; w != NULL && w != wp; w = W_NEXT(w))
7064 	++i;
7065 
7066     if (w == NULL)
7067 	return 0;
7068     else
7069 	return i;
7070 }
7071 
7072     int
7073 get_tab_number(tabpage_T *tp UNUSED)
7074 {
7075     int		i = 1;
7076     tabpage_T	*t;
7077 
7078     for (t = first_tabpage; t != NULL && t != tp; t = t->tp_next)
7079 	++i;
7080 
7081     if (t == NULL)
7082 	return 0;
7083     else
7084 	return i;
7085 }
7086 #endif
7087 
7088 /*
7089  * Return TRUE if "topfrp" and its children are at the right height.
7090  */
7091     static int
7092 frame_check_height(frame_T *topfrp, int height)
7093 {
7094     frame_T *frp;
7095 
7096     if (topfrp->fr_height != height)
7097 	return FALSE;
7098 
7099     if (topfrp->fr_layout == FR_ROW)
7100 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
7101 	    if (frp->fr_height != height)
7102 		return FALSE;
7103 
7104     return TRUE;
7105 }
7106 
7107 /*
7108  * Return TRUE if "topfrp" and its children are at the right width.
7109  */
7110     static int
7111 frame_check_width(frame_T *topfrp, int width)
7112 {
7113     frame_T *frp;
7114 
7115     if (topfrp->fr_width != width)
7116 	return FALSE;
7117 
7118     if (topfrp->fr_layout == FR_COL)
7119 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
7120 	    if (frp->fr_width != width)
7121 		return FALSE;
7122 
7123     return TRUE;
7124 }
7125 
7126 #if defined(FEAT_EVAL) || defined(PROTO)
7127     int
7128 win_getid(typval_T *argvars)
7129 {
7130     int	    winnr;
7131     win_T   *wp;
7132 
7133     if (argvars[0].v_type == VAR_UNKNOWN)
7134 	return curwin->w_id;
7135     winnr = get_tv_number(&argvars[0]);
7136     if (winnr > 0)
7137     {
7138 	if (argvars[1].v_type == VAR_UNKNOWN)
7139 	    wp = firstwin;
7140 	else
7141 	{
7142 	    tabpage_T	*tp;
7143 	    int		tabnr = get_tv_number(&argvars[1]);
7144 
7145 	    FOR_ALL_TABPAGES(tp)
7146 		if (--tabnr == 0)
7147 		    break;
7148 	    if (tp == NULL)
7149 		return -1;
7150 	    if (tp == curtab)
7151 		wp = firstwin;
7152 	    else
7153 		wp = tp->tp_firstwin;
7154 	}
7155 	for ( ; wp != NULL; wp = wp->w_next)
7156 	    if (--winnr == 0)
7157 		return wp->w_id;
7158     }
7159     return 0;
7160 }
7161 
7162     int
7163 win_gotoid(typval_T *argvars)
7164 {
7165     win_T	*wp;
7166     tabpage_T   *tp;
7167     int		id = get_tv_number(&argvars[0]);
7168 
7169     FOR_ALL_TAB_WINDOWS(tp, wp)
7170 	    if (wp->w_id == id)
7171 	    {
7172 		goto_tabpage_win(tp, wp);
7173 		return 1;
7174 	    }
7175     return 0;
7176 }
7177 
7178     void
7179 win_id2tabwin(typval_T *argvars, list_T *list)
7180 {
7181     win_T	*wp;
7182     tabpage_T   *tp;
7183     int		winnr = 1;
7184     int		tabnr = 1;
7185     int		id = get_tv_number(&argvars[0]);
7186 
7187     FOR_ALL_TABPAGES(tp)
7188     {
7189 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
7190 	{
7191 	    if (wp->w_id == id)
7192 	    {
7193 		list_append_number(list, tabnr);
7194 		list_append_number(list, winnr);
7195 		return;
7196 	    }
7197 	    ++winnr;
7198 	}
7199 	++tabnr;
7200 	winnr = 1;
7201     }
7202     list_append_number(list, 0);
7203     list_append_number(list, 0);
7204 }
7205 
7206     win_T *
7207 win_id2wp(typval_T *argvars)
7208 {
7209     win_T	*wp;
7210     tabpage_T   *tp;
7211     int		id = get_tv_number(&argvars[0]);
7212 
7213     FOR_ALL_TAB_WINDOWS(tp, wp)
7214 	if (wp->w_id == id)
7215 	    return wp;
7216 
7217     return NULL;
7218 }
7219 
7220     int
7221 win_id2win(typval_T *argvars)
7222 {
7223     win_T   *wp;
7224     int	    nr = 1;
7225     int	    id = get_tv_number(&argvars[0]);
7226 
7227     FOR_ALL_WINDOWS(wp)
7228     {
7229 	if (wp->w_id == id)
7230 	    return nr;
7231 	++nr;
7232     }
7233     return 0;
7234 }
7235 
7236     void
7237 win_findbuf(typval_T *argvars, list_T *list)
7238 {
7239     win_T	*wp;
7240     tabpage_T   *tp;
7241     int		bufnr = get_tv_number(&argvars[0]);
7242 
7243     FOR_ALL_TAB_WINDOWS(tp, wp)
7244 	    if (wp->w_buffer->b_fnum == bufnr)
7245 		list_append_number(list, wp->w_id);
7246 }
7247 
7248 /*
7249  * Get the layout of the given tab page for winlayout().
7250  */
7251     void
7252 get_framelayout(frame_T *fr, list_T *l, int outer)
7253 {
7254     frame_T	*child;
7255     list_T	*fr_list;
7256     list_T	*win_list;
7257 
7258     if (fr == NULL)
7259 	return;
7260 
7261     if (outer)
7262 	// outermost call from f_winlayout()
7263 	fr_list = l;
7264     else
7265     {
7266 	fr_list = list_alloc();
7267 	if (fr_list == NULL)
7268 	    return;
7269 	list_append_list(l, fr_list);
7270     }
7271 
7272     if (fr->fr_layout == FR_LEAF)
7273     {
7274 	if (fr->fr_win != NULL)
7275 	{
7276 	    list_append_string(fr_list, (char_u *)"leaf", -1);
7277 	    list_append_number(fr_list, fr->fr_win->w_id);
7278 	}
7279     }
7280     else
7281     {
7282 	list_append_string(fr_list,
7283 	     fr->fr_layout == FR_ROW ?  (char_u *)"row" : (char_u *)"col", -1);
7284 
7285 	win_list = list_alloc();
7286 	if (win_list == NULL)
7287 	    return;
7288 	list_append_list(fr_list, win_list);
7289 	child = fr->fr_child;
7290 	while (child != NULL)
7291 	{
7292 	    get_framelayout(child, win_list, FALSE);
7293 	    child = child->fr_next;
7294 	}
7295     }
7296 }
7297 #endif
7298