xref: /vim-8.2.3635/src/window.c (revision cd5c8f82)
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 #if defined(FEAT_WINDOWS) || defined(PROTO)
14 static void cmd_with_count(char *cmd, char_u *bufp, size_t bufsize, long Prenum);
15 static void win_init(win_T *newp, win_T *oldp, int flags);
16 static void win_init_some(win_T *newp, win_T *oldp);
17 static void frame_comp_pos(frame_T *topfrp, int *row, int *col);
18 static void frame_setheight(frame_T *curfrp, int height);
19 static void frame_setwidth(frame_T *curfrp, int width);
20 static void win_exchange(long);
21 static void win_rotate(int, int);
22 static void win_totop(int size, int flags);
23 static void win_equal_rec(win_T *next_curwin, int current, frame_T *topfr, int dir, int col, int row, int width, int height);
24 static int last_window(void);
25 static int close_last_window_tabpage(win_T *win, int free_buf, tabpage_T *prev_curtab);
26 static win_T *win_free_mem(win_T *win, int *dirp, tabpage_T *tp);
27 static frame_T *win_altframe(win_T *win, tabpage_T *tp);
28 static tabpage_T *alt_tabpage(void);
29 static win_T *frame2win(frame_T *frp);
30 static int frame_has_win(frame_T *frp, win_T *wp);
31 static void frame_new_height(frame_T *topfrp, int height, int topfirst, int wfh);
32 static int frame_fixed_height(frame_T *frp);
33 static int frame_fixed_width(frame_T *frp);
34 static void frame_add_statusline(frame_T *frp);
35 static void frame_new_width(frame_T *topfrp, int width, int leftfirst, int wfw);
36 static void frame_add_vsep(frame_T *frp);
37 static int frame_minwidth(frame_T *topfrp, win_T *next_curwin);
38 static void frame_fix_width(win_T *wp);
39 #endif
40 static int win_alloc_firstwin(win_T *oldwin);
41 static void new_frame(win_T *wp);
42 #if defined(FEAT_WINDOWS) || defined(PROTO)
43 static tabpage_T *alloc_tabpage(void);
44 static int leave_tabpage(buf_T *new_curbuf, int trigger_leave_autocmds);
45 static void enter_tabpage(tabpage_T *tp, buf_T *old_curbuf, int trigger_enter_autocmds, int trigger_leave_autocmds);
46 static void frame_fix_height(win_T *wp);
47 static int frame_minheight(frame_T *topfrp, win_T *next_curwin);
48 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);
49 static void win_free(win_T *wp, tabpage_T *tp);
50 static void frame_append(frame_T *after, frame_T *frp);
51 static void frame_insert(frame_T *before, frame_T *frp);
52 static void frame_remove(frame_T *frp);
53 static void win_goto_ver(int up, long count);
54 static void win_goto_hor(int left, long count);
55 static void frame_add_height(frame_T *frp, int n);
56 static void last_status_rec(frame_T *fr, int statusline);
57 
58 static void make_snapshot_rec(frame_T *fr, frame_T **frp);
59 static void clear_snapshot(tabpage_T *tp, int idx);
60 static void clear_snapshot_rec(frame_T *fr);
61 static int check_snapshot_rec(frame_T *sn, frame_T *fr);
62 static win_T *restore_snapshot_rec(frame_T *sn, frame_T *fr);
63 
64 static int frame_check_height(frame_T *topfrp, int height);
65 static int frame_check_width(frame_T *topfrp, int width);
66 
67 #endif /* FEAT_WINDOWS */
68 
69 static win_T *win_alloc(win_T *after, int hidden);
70 
71 #define URL_SLASH	1		/* path_is_url() has found "://" */
72 #define URL_BACKSLASH	2		/* path_is_url() has found ":\\" */
73 
74 #define NOWIN		(win_T *)-1	/* non-existing window */
75 
76 #ifdef FEAT_WINDOWS
77 # define ROWS_AVAIL (Rows - p_ch - tabline_height())
78 #else
79 # define ROWS_AVAIL (Rows - p_ch)
80 #endif
81 
82 #if defined(FEAT_WINDOWS) || defined(PROTO)
83 
84 static char *m_onlyone = N_("Already only one window");
85 
86 /*
87  * all CTRL-W window commands are handled here, called from normal_cmd().
88  */
89     void
90 do_window(
91     int		nchar,
92     long	Prenum,
93     int		xchar)	    /* extra char from ":wincmd gx" or NUL */
94 {
95     long	Prenum1;
96     win_T	*wp;
97 #if defined(FEAT_SEARCHPATH) || defined(FEAT_FIND_ID)
98     char_u	*ptr;
99     linenr_T    lnum = -1;
100 #endif
101 #ifdef FEAT_FIND_ID
102     int		type = FIND_DEFINE;
103     int		len;
104 #endif
105     char_u	cbuf[40];
106 
107     if (Prenum == 0)
108 	Prenum1 = 1;
109     else
110 	Prenum1 = Prenum;
111 
112 #ifdef FEAT_CMDWIN
113 # define CHECK_CMDWIN if (cmdwin_type != 0) { EMSG(_(e_cmdwin)); break; }
114 #else
115 # define CHECK_CMDWIN
116 #endif
117 
118     switch (nchar)
119     {
120 /* split current window in two parts, horizontally */
121     case 'S':
122     case Ctrl_S:
123     case 's':
124 		CHECK_CMDWIN
125 		reset_VIsual_and_resel();	/* stop Visual mode */
126 #ifdef FEAT_QUICKFIX
127 		/* When splitting the quickfix window open a new buffer in it,
128 		 * don't replicate the quickfix buffer. */
129 		if (bt_quickfix(curbuf))
130 		    goto newwindow;
131 #endif
132 #ifdef FEAT_GUI
133 		need_mouse_correct = TRUE;
134 #endif
135 		(void)win_split((int)Prenum, 0);
136 		break;
137 
138 /* split current window in two parts, vertically */
139     case Ctrl_V:
140     case 'v':
141 		CHECK_CMDWIN
142 		reset_VIsual_and_resel();	/* stop Visual mode */
143 #ifdef FEAT_QUICKFIX
144 		/* When splitting the quickfix window open a new buffer in it,
145 		 * don't replicate the quickfix buffer. */
146 		if (bt_quickfix(curbuf))
147 		    goto newwindow;
148 #endif
149 #ifdef FEAT_GUI
150 		need_mouse_correct = TRUE;
151 #endif
152 		(void)win_split((int)Prenum, WSP_VERT);
153 		break;
154 
155 /* split current window and edit alternate file */
156     case Ctrl_HAT:
157     case '^':
158 		CHECK_CMDWIN
159 		reset_VIsual_and_resel();	/* stop Visual mode */
160 		cmd_with_count("split #", cbuf, sizeof(cbuf), Prenum);
161 		do_cmdline_cmd(cbuf);
162 		break;
163 
164 /* open new window */
165     case Ctrl_N:
166     case 'n':
167 		CHECK_CMDWIN
168 		reset_VIsual_and_resel();	/* stop Visual mode */
169 #ifdef FEAT_QUICKFIX
170 newwindow:
171 #endif
172 		if (Prenum)
173 		    /* window height */
174 		    vim_snprintf((char *)cbuf, sizeof(cbuf) - 5, "%ld", Prenum);
175 		else
176 		    cbuf[0] = NUL;
177 #if defined(FEAT_QUICKFIX)
178 		if (nchar == 'v' || nchar == Ctrl_V)
179 		    STRCAT(cbuf, "v");
180 #endif
181 		STRCAT(cbuf, "new");
182 		do_cmdline_cmd(cbuf);
183 		break;
184 
185 /* quit current window */
186     case Ctrl_Q:
187     case 'q':
188 		reset_VIsual_and_resel();	/* stop Visual mode */
189 		cmd_with_count("quit", cbuf, sizeof(cbuf), Prenum);
190 		do_cmdline_cmd(cbuf);
191 		break;
192 
193 /* close current window */
194     case Ctrl_C:
195     case 'c':
196 		reset_VIsual_and_resel();	/* stop Visual mode */
197 		cmd_with_count("close", cbuf, sizeof(cbuf), Prenum);
198 		do_cmdline_cmd(cbuf);
199 		break;
200 
201 #if defined(FEAT_WINDOWS) && defined(FEAT_QUICKFIX)
202 /* close preview window */
203     case Ctrl_Z:
204     case 'z':
205 		CHECK_CMDWIN
206 		reset_VIsual_and_resel();	/* stop Visual mode */
207 		do_cmdline_cmd((char_u *)"pclose");
208 		break;
209 
210 /* cursor to preview window */
211     case 'P':
212 		FOR_ALL_WINDOWS(wp)
213 		    if (wp->w_p_pvw)
214 			break;
215 		if (wp == NULL)
216 		    EMSG(_("E441: There is no preview window"));
217 		else
218 		    win_goto(wp);
219 		break;
220 #endif
221 
222 /* close all but current window */
223     case Ctrl_O:
224     case 'o':
225 		CHECK_CMDWIN
226 		reset_VIsual_and_resel();	/* stop Visual mode */
227 		cmd_with_count("only", cbuf, sizeof(cbuf), Prenum);
228 		do_cmdline_cmd(cbuf);
229 		break;
230 
231 /* cursor to next window with wrap around */
232     case Ctrl_W:
233     case 'w':
234 /* cursor to previous window with wrap around */
235     case 'W':
236 		CHECK_CMDWIN
237 		if (ONE_WINDOW && Prenum != 1)	/* just one window */
238 		    beep_flush();
239 		else
240 		{
241 		    if (Prenum)			/* go to specified window */
242 		    {
243 			for (wp = firstwin; --Prenum > 0; )
244 			{
245 			    if (wp->w_next == NULL)
246 				break;
247 			    else
248 				wp = wp->w_next;
249 			}
250 		    }
251 		    else
252 		    {
253 			if (nchar == 'W')	    /* go to previous window */
254 			{
255 			    wp = curwin->w_prev;
256 			    if (wp == NULL)
257 				wp = lastwin;	    /* wrap around */
258 			}
259 			else			    /* go to next window */
260 			{
261 			    wp = curwin->w_next;
262 			    if (wp == NULL)
263 				wp = firstwin;	    /* wrap around */
264 			}
265 		    }
266 		    win_goto(wp);
267 		}
268 		break;
269 
270 /* cursor to window below */
271     case 'j':
272     case K_DOWN:
273     case Ctrl_J:
274 		CHECK_CMDWIN
275 		win_goto_ver(FALSE, Prenum1);
276 		break;
277 
278 /* cursor to window above */
279     case 'k':
280     case K_UP:
281     case Ctrl_K:
282 		CHECK_CMDWIN
283 		win_goto_ver(TRUE, Prenum1);
284 		break;
285 
286 /* cursor to left window */
287     case 'h':
288     case K_LEFT:
289     case Ctrl_H:
290     case K_BS:
291 		CHECK_CMDWIN
292 		win_goto_hor(TRUE, Prenum1);
293 		break;
294 
295 /* cursor to right window */
296     case 'l':
297     case K_RIGHT:
298     case Ctrl_L:
299 		CHECK_CMDWIN
300 		win_goto_hor(FALSE, Prenum1);
301 		break;
302 
303 /* move window to new tab page */
304     case 'T':
305 		if (one_window())
306 		    MSG(_(m_onlyone));
307 		else
308 		{
309 		    tabpage_T	*oldtab = curtab;
310 		    tabpage_T	*newtab;
311 
312 		    /* First create a new tab with the window, then go back to
313 		     * the old tab and close the window there. */
314 		    wp = curwin;
315 		    if (win_new_tabpage((int)Prenum) == OK
316 						     && valid_tabpage(oldtab))
317 		    {
318 			newtab = curtab;
319 			goto_tabpage_tp(oldtab, TRUE, TRUE);
320 			if (curwin == wp)
321 			    win_close(curwin, FALSE);
322 			if (valid_tabpage(newtab))
323 			    goto_tabpage_tp(newtab, TRUE, TRUE);
324 		    }
325 		}
326 		break;
327 
328 /* cursor to top-left window */
329     case 't':
330     case Ctrl_T:
331 		win_goto(firstwin);
332 		break;
333 
334 /* cursor to bottom-right window */
335     case 'b':
336     case Ctrl_B:
337 		win_goto(lastwin);
338 		break;
339 
340 /* cursor to last accessed (previous) window */
341     case 'p':
342     case Ctrl_P:
343 		if (!win_valid(prevwin))
344 		    beep_flush();
345 		else
346 		    win_goto(prevwin);
347 		break;
348 
349 /* exchange current and next window */
350     case 'x':
351     case Ctrl_X:
352 		CHECK_CMDWIN
353 		win_exchange(Prenum);
354 		break;
355 
356 /* rotate windows downwards */
357     case Ctrl_R:
358     case 'r':
359 		CHECK_CMDWIN
360 		reset_VIsual_and_resel();	/* stop Visual mode */
361 		win_rotate(FALSE, (int)Prenum1);    /* downwards */
362 		break;
363 
364 /* rotate windows upwards */
365     case 'R':
366 		CHECK_CMDWIN
367 		reset_VIsual_and_resel();	/* stop Visual mode */
368 		win_rotate(TRUE, (int)Prenum1);	    /* upwards */
369 		break;
370 
371 /* move window to the very top/bottom/left/right */
372     case 'K':
373     case 'J':
374     case 'H':
375     case 'L':
376 		CHECK_CMDWIN
377 		win_totop((int)Prenum,
378 			((nchar == 'H' || nchar == 'L') ? WSP_VERT : 0)
379 			| ((nchar == 'H' || nchar == 'K') ? WSP_TOP : WSP_BOT));
380 		break;
381 
382 /* make all windows the same height */
383     case '=':
384 #ifdef FEAT_GUI
385 		need_mouse_correct = TRUE;
386 #endif
387 		win_equal(NULL, FALSE, 'b');
388 		break;
389 
390 /* increase current window height */
391     case '+':
392 #ifdef FEAT_GUI
393 		need_mouse_correct = TRUE;
394 #endif
395 		win_setheight(curwin->w_height + (int)Prenum1);
396 		break;
397 
398 /* decrease current window height */
399     case '-':
400 #ifdef FEAT_GUI
401 		need_mouse_correct = TRUE;
402 #endif
403 		win_setheight(curwin->w_height - (int)Prenum1);
404 		break;
405 
406 /* set current window height */
407     case Ctrl__:
408     case '_':
409 #ifdef FEAT_GUI
410 		need_mouse_correct = TRUE;
411 #endif
412 		win_setheight(Prenum ? (int)Prenum : 9999);
413 		break;
414 
415 /* increase current window width */
416     case '>':
417 #ifdef FEAT_GUI
418 		need_mouse_correct = TRUE;
419 #endif
420 		win_setwidth(curwin->w_width + (int)Prenum1);
421 		break;
422 
423 /* decrease current window width */
424     case '<':
425 #ifdef FEAT_GUI
426 		need_mouse_correct = TRUE;
427 #endif
428 		win_setwidth(curwin->w_width - (int)Prenum1);
429 		break;
430 
431 /* set current window width */
432     case '|':
433 #ifdef FEAT_GUI
434 		need_mouse_correct = TRUE;
435 #endif
436 		win_setwidth(Prenum != 0 ? (int)Prenum : 9999);
437 		break;
438 
439 /* jump to tag and split window if tag exists (in preview window) */
440 #if defined(FEAT_QUICKFIX)
441     case '}':
442 		CHECK_CMDWIN
443 		if (Prenum)
444 		    g_do_tagpreview = Prenum;
445 		else
446 		    g_do_tagpreview = p_pvh;
447 		/*FALLTHROUGH*/
448 #endif
449     case ']':
450     case Ctrl_RSB:
451 		CHECK_CMDWIN
452 		/* keep Visual mode, can select words to use as a tag */
453 		if (Prenum)
454 		    postponed_split = Prenum;
455 		else
456 		    postponed_split = -1;
457 #ifdef FEAT_QUICKFIX
458 		if (nchar != '}')
459 		    g_do_tagpreview = 0;
460 #endif
461 
462 		/* Execute the command right here, required when "wincmd ]"
463 		 * was used in a function. */
464 		do_nv_ident(Ctrl_RSB, NUL);
465 		break;
466 
467 #ifdef FEAT_SEARCHPATH
468 /* edit file name under cursor in a new window */
469     case 'f':
470     case 'F':
471     case Ctrl_F:
472 wingotofile:
473 		CHECK_CMDWIN
474 
475 		ptr = grab_file_name(Prenum1, &lnum);
476 		if (ptr != NULL)
477 		{
478 		    tabpage_T	*oldtab = curtab;
479 		    win_T	*oldwin = curwin;
480 # ifdef FEAT_GUI
481 		    need_mouse_correct = TRUE;
482 # endif
483 		    setpcmark();
484 		    if (win_split(0, 0) == OK)
485 		    {
486 			RESET_BINDING(curwin);
487 			if (do_ecmd(0, ptr, NULL, NULL, ECMD_LASTL,
488 						   ECMD_HIDE, NULL) == FAIL)
489 			{
490 			    /* Failed to open the file, close the window
491 			     * opened for it. */
492 			    win_close(curwin, FALSE);
493 			    goto_tabpage_win(oldtab, oldwin);
494 			}
495 			else if (nchar == 'F' && lnum >= 0)
496 			{
497 			    curwin->w_cursor.lnum = lnum;
498 			    check_cursor_lnum();
499 			    beginline(BL_SOL | BL_FIX);
500 			}
501 		    }
502 		    vim_free(ptr);
503 		}
504 		break;
505 #endif
506 
507 #ifdef FEAT_FIND_ID
508 /* Go to the first occurrence of the identifier under cursor along path in a
509  * new window -- webb
510  */
511     case 'i':			    /* Go to any match */
512     case Ctrl_I:
513 		type = FIND_ANY;
514 		/* FALLTHROUGH */
515     case 'd':			    /* Go to definition, using 'define' */
516     case Ctrl_D:
517 		CHECK_CMDWIN
518 		if ((len = find_ident_under_cursor(&ptr, FIND_IDENT)) == 0)
519 		    break;
520 		find_pattern_in_path(ptr, 0, len, TRUE,
521 			Prenum == 0 ? TRUE : FALSE, type,
522 			Prenum1, ACTION_SPLIT, (linenr_T)1, (linenr_T)MAXLNUM);
523 		curwin->w_set_curswant = TRUE;
524 		break;
525 #endif
526 
527     case K_KENTER:
528     case CAR:
529 #if defined(FEAT_QUICKFIX)
530 		/*
531 		 * In a quickfix window a <CR> jumps to the error under the
532 		 * cursor in a new window.
533 		 */
534 		if (bt_quickfix(curbuf))
535 		{
536 		    sprintf((char *)cbuf, "split +%ld%s",
537 				(long)curwin->w_cursor.lnum,
538 				(curwin->w_llist_ref == NULL) ? "cc" : "ll");
539 		    do_cmdline_cmd(cbuf);
540 		}
541 #endif
542 		break;
543 
544 
545 /* CTRL-W g  extended commands */
546     case 'g':
547     case Ctrl_G:
548 		CHECK_CMDWIN
549 #ifdef USE_ON_FLY_SCROLL
550 		dont_scroll = TRUE;		/* disallow scrolling here */
551 #endif
552 		++no_mapping;
553 		++allow_keys;   /* no mapping for xchar, but allow key codes */
554 		if (xchar == NUL)
555 		    xchar = plain_vgetc();
556 		LANGMAP_ADJUST(xchar, TRUE);
557 		--no_mapping;
558 		--allow_keys;
559 #ifdef FEAT_CMDL_INFO
560 		(void)add_to_showcmd(xchar);
561 #endif
562 		switch (xchar)
563 		{
564 #if defined(FEAT_QUICKFIX)
565 		    case '}':
566 			xchar = Ctrl_RSB;
567 			if (Prenum)
568 			    g_do_tagpreview = Prenum;
569 			else
570 			    g_do_tagpreview = p_pvh;
571 			/*FALLTHROUGH*/
572 #endif
573 		    case ']':
574 		    case Ctrl_RSB:
575 			/* keep Visual mode, can select words to use as a tag */
576 			if (Prenum)
577 			    postponed_split = Prenum;
578 			else
579 			    postponed_split = -1;
580 
581 			/* Execute the command right here, required when
582 			 * "wincmd g}" was used in a function. */
583 			do_nv_ident('g', xchar);
584 			break;
585 
586 #ifdef FEAT_SEARCHPATH
587 		    case 'f':	    /* CTRL-W gf: "gf" in a new tab page */
588 		    case 'F':	    /* CTRL-W gF: "gF" in a new tab page */
589 			cmdmod.tab = tabpage_index(curtab) + 1;
590 			nchar = xchar;
591 			goto wingotofile;
592 #endif
593 		    default:
594 			beep_flush();
595 			break;
596 		}
597 		break;
598 
599     default:	beep_flush();
600 		break;
601     }
602 }
603 
604 /*
605  * Figure out the address type for ":wnncmd".
606  */
607     void
608 get_wincmd_addr_type(char_u *arg, exarg_T *eap)
609 {
610     switch (*arg)
611     {
612     case 'S':
613     case Ctrl_S:
614     case 's':
615     case Ctrl_N:
616     case 'n':
617     case 'j':
618     case Ctrl_J:
619     case 'k':
620     case Ctrl_K:
621     case 'T':
622     case Ctrl_R:
623     case 'r':
624     case 'R':
625     case 'K':
626     case 'J':
627     case '+':
628     case '-':
629     case Ctrl__:
630     case '_':
631     case '|':
632     case ']':
633     case Ctrl_RSB:
634     case 'g':
635     case Ctrl_G:
636     case Ctrl_V:
637     case 'v':
638     case 'h':
639     case Ctrl_H:
640     case 'l':
641     case Ctrl_L:
642     case 'H':
643     case 'L':
644     case '>':
645     case '<':
646 #if defined(FEAT_QUICKFIX)
647     case '}':
648 #endif
649 #ifdef FEAT_SEARCHPATH
650     case 'f':
651     case 'F':
652     case Ctrl_F:
653 #endif
654 #ifdef FEAT_FIND_ID
655     case 'i':
656     case Ctrl_I:
657     case 'd':
658     case Ctrl_D:
659 #endif
660 		/* window size or any count */
661 		eap->addr_type = ADDR_LINES;
662 		break;
663 
664     case Ctrl_HAT:
665     case '^':
666 		/* buffer number */
667 		eap->addr_type = ADDR_BUFFERS;
668 		break;
669 
670     case Ctrl_Q:
671     case 'q':
672     case Ctrl_C:
673     case 'c':
674     case Ctrl_O:
675     case 'o':
676     case Ctrl_W:
677     case 'w':
678     case 'W':
679     case 'x':
680     case Ctrl_X:
681 		/* window number */
682 		eap->addr_type = ADDR_WINDOWS;
683 		break;
684 
685 #if defined(FEAT_QUICKFIX)
686     case Ctrl_Z:
687     case 'z':
688     case 'P':
689 #endif
690     case 't':
691     case Ctrl_T:
692     case 'b':
693     case Ctrl_B:
694     case 'p':
695     case Ctrl_P:
696     case '=':
697     case CAR:
698 		/* no count */
699 		eap->addr_type = 0;
700 		break;
701     }
702 }
703 
704     static void
705 cmd_with_count(
706     char	*cmd,
707     char_u	*bufp,
708     size_t	bufsize,
709     long	Prenum)
710 {
711     size_t	len = STRLEN(cmd);
712 
713     STRCPY(bufp, cmd);
714     if (Prenum > 0)
715 	vim_snprintf((char *)bufp + len, bufsize - len, "%ld", Prenum);
716 }
717 
718 /*
719  * split the current window, implements CTRL-W s and :split
720  *
721  * "size" is the height or width for the new window, 0 to use half of current
722  * height or width.
723  *
724  * "flags":
725  * WSP_ROOM: require enough room for new window
726  * WSP_VERT: vertical split.
727  * WSP_TOP:  open window at the top-left of the shell (help window).
728  * WSP_BOT:  open window at the bottom-right of the shell (quickfix window).
729  * WSP_HELP: creating the help window, keep layout snapshot
730  *
731  * return FAIL for failure, OK otherwise
732  */
733     int
734 win_split(int size, int flags)
735 {
736     /* When the ":tab" modifier was used open a new tab page instead. */
737     if (may_open_tabpage() == OK)
738 	return OK;
739 
740     /* Add flags from ":vertical", ":topleft" and ":botright". */
741     flags |= cmdmod.split;
742     if ((flags & WSP_TOP) && (flags & WSP_BOT))
743     {
744 	EMSG(_("E442: Can't split topleft and botright at the same time"));
745 	return FAIL;
746     }
747 
748     /* When creating the help window make a snapshot of the window layout.
749      * Otherwise clear the snapshot, it's now invalid. */
750     if (flags & WSP_HELP)
751 	make_snapshot(SNAP_HELP_IDX);
752     else
753 	clear_snapshot(curtab, SNAP_HELP_IDX);
754 
755     return win_split_ins(size, flags, NULL, 0);
756 }
757 
758 /*
759  * When "new_wp" is NULL: split the current window in two.
760  * When "new_wp" is not NULL: insert this window at the far
761  * top/left/right/bottom.
762  * return FAIL for failure, OK otherwise
763  */
764     int
765 win_split_ins(
766     int		size,
767     int		flags,
768     win_T	*new_wp,
769     int		dir)
770 {
771     win_T	*wp = new_wp;
772     win_T	*oldwin;
773     int		new_size = size;
774     int		i;
775     int		need_status = 0;
776     int		do_equal = FALSE;
777     int		needed;
778     int		available;
779     int		oldwin_height = 0;
780     int		layout;
781     frame_T	*frp, *curfrp, *frp2, *prevfrp;
782     int		before;
783     int		minheight;
784     int		wmh1;
785 
786     if (flags & WSP_TOP)
787 	oldwin = firstwin;
788     else if (flags & WSP_BOT)
789 	oldwin = lastwin;
790     else
791 	oldwin = curwin;
792 
793     /* add a status line when p_ls == 1 and splitting the first window */
794     if (ONE_WINDOW && p_ls == 1 && oldwin->w_status_height == 0)
795     {
796 	if (oldwin->w_height <= p_wmh && new_wp == NULL)
797 	{
798 	    EMSG(_(e_noroom));
799 	    return FAIL;
800 	}
801 	need_status = STATUS_HEIGHT;
802     }
803 
804 #ifdef FEAT_GUI
805     /* May be needed for the scrollbars that are going to change. */
806     if (gui.in_use)
807 	out_flush();
808 #endif
809 
810     if (flags & WSP_VERT)
811     {
812 	int	wmw1;
813 	int	minwidth;
814 
815 	layout = FR_ROW;
816 
817 	/*
818 	 * Check if we are able to split the current window and compute its
819 	 * width.
820 	 */
821 	/* Current window requires at least 1 space. */
822 	wmw1 = (p_wmw == 0 ? 1 : p_wmw);
823 	needed = wmw1 + 1;
824 	if (flags & WSP_ROOM)
825 	    needed += p_wiw - wmw1;
826 	if (flags & (WSP_BOT | WSP_TOP))
827 	{
828 	    minwidth = frame_minwidth(topframe, NOWIN);
829 	    available = topframe->fr_width;
830 	    needed += minwidth;
831 	}
832 	else if (p_ea)
833 	{
834 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
835 	    prevfrp = oldwin->w_frame;
836 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
837 							frp = frp->fr_parent)
838 	    {
839 		if (frp->fr_layout == FR_ROW)
840 		    for (frp2 = frp->fr_child; frp2 != NULL;
841 							frp2 = frp2->fr_next)
842 			if (frp2 != prevfrp)
843 			    minwidth += frame_minwidth(frp2, NOWIN);
844 		prevfrp = frp;
845 	    }
846 	    available = topframe->fr_width;
847 	    needed += minwidth;
848 	}
849 	else
850 	{
851 	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
852 	    available = oldwin->w_frame->fr_width;
853 	    needed += minwidth;
854 	}
855 	if (available < needed && new_wp == NULL)
856 	{
857 	    EMSG(_(e_noroom));
858 	    return FAIL;
859 	}
860 	if (new_size == 0)
861 	    new_size = oldwin->w_width / 2;
862 	if (new_size > available - minwidth - 1)
863 	    new_size = available - minwidth - 1;
864 	if (new_size < wmw1)
865 	    new_size = wmw1;
866 
867 	/* if it doesn't fit in the current window, need win_equal() */
868 	if (oldwin->w_width - new_size - 1 < p_wmw)
869 	    do_equal = TRUE;
870 
871 	/* We don't like to take lines for the new window from a
872 	 * 'winfixwidth' window.  Take them from a window to the left or right
873 	 * instead, if possible. Add one for the separator. */
874 	if (oldwin->w_p_wfw)
875 	    win_setwidth_win(oldwin->w_width + new_size + 1, oldwin);
876 
877 	/* Only make all windows the same width if one of them (except oldwin)
878 	 * is wider than one of the split windows. */
879 	if (!do_equal && p_ea && size == 0 && *p_ead != 'v'
880 	   && oldwin->w_frame->fr_parent != NULL)
881 	{
882 	    frp = oldwin->w_frame->fr_parent->fr_child;
883 	    while (frp != NULL)
884 	    {
885 		if (frp->fr_win != oldwin && frp->fr_win != NULL
886 			&& (frp->fr_win->w_width > new_size
887 			    || frp->fr_win->w_width > oldwin->w_width
888 							      - new_size - 1))
889 		{
890 		    do_equal = TRUE;
891 		    break;
892 		}
893 		frp = frp->fr_next;
894 	    }
895 	}
896     }
897     else
898     {
899 	layout = FR_COL;
900 
901 	/*
902 	 * Check if we are able to split the current window and compute its
903 	 * height.
904 	 */
905 	/* Current window requires at least 1 space. */
906 	wmh1 = (p_wmh == 0 ? 1 : p_wmh);
907 	needed = wmh1 + STATUS_HEIGHT;
908 	if (flags & WSP_ROOM)
909 	    needed += p_wh - wmh1;
910 	if (flags & (WSP_BOT | WSP_TOP))
911 	{
912 	    minheight = frame_minheight(topframe, NOWIN) + need_status;
913 	    available = topframe->fr_height;
914 	    needed += minheight;
915 	}
916 	else if (p_ea)
917 	{
918 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
919 	    prevfrp = oldwin->w_frame;
920 	    for (frp = oldwin->w_frame->fr_parent; frp != NULL;
921 							frp = frp->fr_parent)
922 	    {
923 		if (frp->fr_layout == FR_COL)
924 		    for (frp2 = frp->fr_child; frp2 != NULL;
925 							frp2 = frp2->fr_next)
926 			if (frp2 != prevfrp)
927 			    minheight += frame_minheight(frp2, NOWIN);
928 		prevfrp = frp;
929 	    }
930 	    available = topframe->fr_height;
931 	    needed += minheight;
932 	}
933 	else
934 	{
935 	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
936 	    available = oldwin->w_frame->fr_height;
937 	    needed += minheight;
938 	}
939 	if (available < needed && new_wp == NULL)
940 	{
941 	    EMSG(_(e_noroom));
942 	    return FAIL;
943 	}
944 	oldwin_height = oldwin->w_height;
945 	if (need_status)
946 	{
947 	    oldwin->w_status_height = STATUS_HEIGHT;
948 	    oldwin_height -= STATUS_HEIGHT;
949 	}
950 	if (new_size == 0)
951 	    new_size = oldwin_height / 2;
952 	if (new_size > available - minheight - STATUS_HEIGHT)
953 	    new_size = available - minheight - STATUS_HEIGHT;
954 	if (new_size < wmh1)
955 	    new_size = wmh1;
956 
957 	/* if it doesn't fit in the current window, need win_equal() */
958 	if (oldwin_height - new_size - STATUS_HEIGHT < p_wmh)
959 	    do_equal = TRUE;
960 
961 	/* We don't like to take lines for the new window from a
962 	 * 'winfixheight' window.  Take them from a window above or below
963 	 * instead, if possible. */
964 	if (oldwin->w_p_wfh)
965 	{
966 	    win_setheight_win(oldwin->w_height + new_size + STATUS_HEIGHT,
967 								      oldwin);
968 	    oldwin_height = oldwin->w_height;
969 	    if (need_status)
970 		oldwin_height -= STATUS_HEIGHT;
971 	}
972 
973 	/* Only make all windows the same height if one of them (except oldwin)
974 	 * is higher than one of the split windows. */
975 	if (!do_equal && p_ea && size == 0 && *p_ead != 'h'
976 	   && oldwin->w_frame->fr_parent != NULL)
977 	{
978 	    frp = oldwin->w_frame->fr_parent->fr_child;
979 	    while (frp != NULL)
980 	    {
981 		if (frp->fr_win != oldwin && frp->fr_win != NULL
982 			&& (frp->fr_win->w_height > new_size
983 			    || frp->fr_win->w_height > oldwin_height - new_size
984 							      - STATUS_HEIGHT))
985 		{
986 		    do_equal = TRUE;
987 		    break;
988 		}
989 		frp = frp->fr_next;
990 	    }
991 	}
992     }
993 
994     /*
995      * allocate new window structure and link it in the window list
996      */
997     if ((flags & WSP_TOP) == 0
998 	    && ((flags & WSP_BOT)
999 		|| (flags & WSP_BELOW)
1000 		|| (!(flags & WSP_ABOVE)
1001 		    && ( (flags & WSP_VERT) ? p_spr : p_sb))))
1002     {
1003 	/* new window below/right of current one */
1004 	if (new_wp == NULL)
1005 	    wp = win_alloc(oldwin, FALSE);
1006 	else
1007 	    win_append(oldwin, wp);
1008     }
1009     else
1010     {
1011 	if (new_wp == NULL)
1012 	    wp = win_alloc(oldwin->w_prev, FALSE);
1013 	else
1014 	    win_append(oldwin->w_prev, wp);
1015     }
1016 
1017     if (new_wp == NULL)
1018     {
1019 	if (wp == NULL)
1020 	    return FAIL;
1021 
1022 	new_frame(wp);
1023 	if (wp->w_frame == NULL)
1024 	{
1025 	    win_free(wp, NULL);
1026 	    return FAIL;
1027 	}
1028 
1029 	/* make the contents of the new window the same as the current one */
1030 	win_init(wp, curwin, flags);
1031     }
1032 
1033     /*
1034      * Reorganise the tree of frames to insert the new window.
1035      */
1036     if (flags & (WSP_TOP | WSP_BOT))
1037     {
1038 	if ((topframe->fr_layout == FR_COL && (flags & WSP_VERT) == 0)
1039 	    || (topframe->fr_layout == FR_ROW && (flags & WSP_VERT) != 0))
1040 	{
1041 	    curfrp = topframe->fr_child;
1042 	    if (flags & WSP_BOT)
1043 		while (curfrp->fr_next != NULL)
1044 		    curfrp = curfrp->fr_next;
1045 	}
1046 	else
1047 	    curfrp = topframe;
1048 	before = (flags & WSP_TOP);
1049     }
1050     else
1051     {
1052 	curfrp = oldwin->w_frame;
1053 	if (flags & WSP_BELOW)
1054 	    before = FALSE;
1055 	else if (flags & WSP_ABOVE)
1056 	    before = TRUE;
1057 	else if (flags & WSP_VERT)
1058 	    before = !p_spr;
1059 	else
1060 	    before = !p_sb;
1061     }
1062     if (curfrp->fr_parent == NULL || curfrp->fr_parent->fr_layout != layout)
1063     {
1064 	/* Need to create a new frame in the tree to make a branch. */
1065 	frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
1066 	*frp = *curfrp;
1067 	curfrp->fr_layout = layout;
1068 	frp->fr_parent = curfrp;
1069 	frp->fr_next = NULL;
1070 	frp->fr_prev = NULL;
1071 	curfrp->fr_child = frp;
1072 	curfrp->fr_win = NULL;
1073 	curfrp = frp;
1074 	if (frp->fr_win != NULL)
1075 	    oldwin->w_frame = frp;
1076 	else
1077 	    for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
1078 		frp->fr_parent = curfrp;
1079     }
1080 
1081     if (new_wp == NULL)
1082 	frp = wp->w_frame;
1083     else
1084 	frp = new_wp->w_frame;
1085     frp->fr_parent = curfrp->fr_parent;
1086 
1087     /* Insert the new frame at the right place in the frame list. */
1088     if (before)
1089 	frame_insert(curfrp, frp);
1090     else
1091 	frame_append(curfrp, frp);
1092 
1093     /* Set w_fraction now so that the cursor keeps the same relative
1094      * vertical position. */
1095     if (oldwin->w_height > 0)
1096 	set_fraction(oldwin);
1097     wp->w_fraction = oldwin->w_fraction;
1098 
1099     if (flags & WSP_VERT)
1100     {
1101 	wp->w_p_scr = curwin->w_p_scr;
1102 
1103 	if (need_status)
1104 	{
1105 	    win_new_height(oldwin, oldwin->w_height - 1);
1106 	    oldwin->w_status_height = need_status;
1107 	}
1108 	if (flags & (WSP_TOP | WSP_BOT))
1109 	{
1110 	    /* set height and row of new window to full height */
1111 	    wp->w_winrow = tabline_height();
1112 	    win_new_height(wp, curfrp->fr_height - (p_ls > 0));
1113 	    wp->w_status_height = (p_ls > 0);
1114 	}
1115 	else
1116 	{
1117 	    /* height and row of new window is same as current window */
1118 	    wp->w_winrow = oldwin->w_winrow;
1119 	    win_new_height(wp, oldwin->w_height);
1120 	    wp->w_status_height = oldwin->w_status_height;
1121 	}
1122 	frp->fr_height = curfrp->fr_height;
1123 
1124 	/* "new_size" of the current window goes to the new window, use
1125 	 * one column for the vertical separator */
1126 	win_new_width(wp, new_size);
1127 	if (before)
1128 	    wp->w_vsep_width = 1;
1129 	else
1130 	{
1131 	    wp->w_vsep_width = oldwin->w_vsep_width;
1132 	    oldwin->w_vsep_width = 1;
1133 	}
1134 	if (flags & (WSP_TOP | WSP_BOT))
1135 	{
1136 	    if (flags & WSP_BOT)
1137 		frame_add_vsep(curfrp);
1138 	    /* Set width of neighbor frame */
1139 	    frame_new_width(curfrp, curfrp->fr_width
1140 		     - (new_size + ((flags & WSP_TOP) != 0)), flags & WSP_TOP,
1141 								       FALSE);
1142 	}
1143 	else
1144 	    win_new_width(oldwin, oldwin->w_width - (new_size + 1));
1145 	if (before)	/* new window left of current one */
1146 	{
1147 	    wp->w_wincol = oldwin->w_wincol;
1148 	    oldwin->w_wincol += new_size + 1;
1149 	}
1150 	else		/* new window right of current one */
1151 	    wp->w_wincol = oldwin->w_wincol + oldwin->w_width + 1;
1152 	frame_fix_width(oldwin);
1153 	frame_fix_width(wp);
1154     }
1155     else
1156     {
1157 	/* width and column of new window is same as current window */
1158 	if (flags & (WSP_TOP | WSP_BOT))
1159 	{
1160 	    wp->w_wincol = 0;
1161 	    win_new_width(wp, Columns);
1162 	    wp->w_vsep_width = 0;
1163 	}
1164 	else
1165 	{
1166 	    wp->w_wincol = oldwin->w_wincol;
1167 	    win_new_width(wp, oldwin->w_width);
1168 	    wp->w_vsep_width = oldwin->w_vsep_width;
1169 	}
1170 	frp->fr_width = curfrp->fr_width;
1171 
1172 	/* "new_size" of the current window goes to the new window, use
1173 	 * one row for the status line */
1174 	win_new_height(wp, new_size);
1175 	if (flags & (WSP_TOP | WSP_BOT))
1176 	{
1177 	    int new_fr_height = curfrp->fr_height - new_size;
1178 
1179 	    if (!((flags & WSP_BOT) && p_ls == 0))
1180 		new_fr_height -= STATUS_HEIGHT;
1181 	    frame_new_height(curfrp, new_fr_height, flags & WSP_TOP, FALSE);
1182 	}
1183 	else
1184 	    win_new_height(oldwin, oldwin_height - (new_size + STATUS_HEIGHT));
1185 	if (before)	/* new window above current one */
1186 	{
1187 	    wp->w_winrow = oldwin->w_winrow;
1188 	    wp->w_status_height = STATUS_HEIGHT;
1189 	    oldwin->w_winrow += wp->w_height + STATUS_HEIGHT;
1190 	}
1191 	else		/* new window below current one */
1192 	{
1193 	    wp->w_winrow = oldwin->w_winrow + oldwin->w_height + STATUS_HEIGHT;
1194 	    wp->w_status_height = oldwin->w_status_height;
1195 	    if (!(flags & WSP_BOT))
1196 		oldwin->w_status_height = STATUS_HEIGHT;
1197 	}
1198 	if (flags & WSP_BOT)
1199 	    frame_add_statusline(curfrp);
1200 	frame_fix_height(wp);
1201 	frame_fix_height(oldwin);
1202     }
1203 
1204     if (flags & (WSP_TOP | WSP_BOT))
1205 	(void)win_comp_pos();
1206 
1207     /*
1208      * Both windows need redrawing
1209      */
1210     redraw_win_later(wp, NOT_VALID);
1211     wp->w_redr_status = TRUE;
1212     redraw_win_later(oldwin, NOT_VALID);
1213     oldwin->w_redr_status = TRUE;
1214 
1215     if (need_status)
1216     {
1217 	msg_row = Rows - 1;
1218 	msg_col = sc_col;
1219 	msg_clr_eos_force();	/* Old command/ruler may still be there */
1220 	comp_col();
1221 	msg_row = Rows - 1;
1222 	msg_col = 0;	/* put position back at start of line */
1223     }
1224 
1225     /*
1226      * equalize the window sizes.
1227      */
1228     if (do_equal || dir != 0)
1229 	win_equal(wp, TRUE,
1230 		(flags & WSP_VERT) ? (dir == 'v' ? 'b' : 'h')
1231 		: dir == 'h' ? 'b' : 'v');
1232 
1233     /* Don't change the window height/width to 'winheight' / 'winwidth' if a
1234      * size was given. */
1235     if (flags & WSP_VERT)
1236     {
1237 	i = p_wiw;
1238 	if (size != 0)
1239 	    p_wiw = size;
1240 
1241 # ifdef FEAT_GUI
1242 	/* When 'guioptions' includes 'L' or 'R' may have to add scrollbars. */
1243 	if (gui.in_use)
1244 	    gui_init_which_components(NULL);
1245 # endif
1246     }
1247     else
1248     {
1249 	i = p_wh;
1250 	if (size != 0)
1251 	    p_wh = size;
1252     }
1253 
1254 #ifdef FEAT_JUMPLIST
1255     /* Keep same changelist position in new window. */
1256     wp->w_changelistidx = oldwin->w_changelistidx;
1257 #endif
1258 
1259     /*
1260      * make the new window the current window
1261      */
1262     win_enter_ext(wp, FALSE, FALSE, TRUE, TRUE, TRUE);
1263     if (flags & WSP_VERT)
1264 	p_wiw = i;
1265     else
1266 	p_wh = i;
1267 
1268     return OK;
1269 }
1270 
1271 
1272 /*
1273  * Initialize window "newp" from window "oldp".
1274  * Used when splitting a window and when creating a new tab page.
1275  * The windows will both edit the same buffer.
1276  * WSP_NEWLOC may be specified in flags to prevent the location list from
1277  * being copied.
1278  */
1279     static void
1280 win_init(win_T *newp, win_T *oldp, int flags UNUSED)
1281 {
1282     int		i;
1283 
1284     newp->w_buffer = oldp->w_buffer;
1285 #ifdef FEAT_SYN_HL
1286     newp->w_s = &(oldp->w_buffer->b_s);
1287 #endif
1288     oldp->w_buffer->b_nwindows++;
1289     newp->w_cursor = oldp->w_cursor;
1290     newp->w_valid = 0;
1291     newp->w_curswant = oldp->w_curswant;
1292     newp->w_set_curswant = oldp->w_set_curswant;
1293     newp->w_topline = oldp->w_topline;
1294 #ifdef FEAT_DIFF
1295     newp->w_topfill = oldp->w_topfill;
1296 #endif
1297     newp->w_leftcol = oldp->w_leftcol;
1298     newp->w_pcmark = oldp->w_pcmark;
1299     newp->w_prev_pcmark = oldp->w_prev_pcmark;
1300     newp->w_alt_fnum = oldp->w_alt_fnum;
1301     newp->w_wrow = oldp->w_wrow;
1302     newp->w_fraction = oldp->w_fraction;
1303     newp->w_prev_fraction_row = oldp->w_prev_fraction_row;
1304 #ifdef FEAT_JUMPLIST
1305     copy_jumplist(oldp, newp);
1306 #endif
1307 #ifdef FEAT_QUICKFIX
1308     if (flags & WSP_NEWLOC)
1309     {
1310 	/* Don't copy the location list.  */
1311 	newp->w_llist = NULL;
1312 	newp->w_llist_ref = NULL;
1313     }
1314     else
1315 	copy_loclist(oldp, newp);
1316 #endif
1317     newp->w_localdir = (oldp->w_localdir == NULL)
1318 				    ? NULL : vim_strsave(oldp->w_localdir);
1319 
1320     /* copy tagstack and folds */
1321     for (i = 0; i < oldp->w_tagstacklen; i++)
1322     {
1323 	newp->w_tagstack[i] = oldp->w_tagstack[i];
1324 	if (newp->w_tagstack[i].tagname != NULL)
1325 	    newp->w_tagstack[i].tagname =
1326 				   vim_strsave(newp->w_tagstack[i].tagname);
1327     }
1328     newp->w_tagstackidx = oldp->w_tagstackidx;
1329     newp->w_tagstacklen = oldp->w_tagstacklen;
1330 #ifdef FEAT_FOLDING
1331     copyFoldingState(oldp, newp);
1332 #endif
1333 
1334     win_init_some(newp, oldp);
1335 
1336 #ifdef FEAT_SYN_HL
1337     check_colorcolumn(newp);
1338 #endif
1339 }
1340 
1341 /*
1342  * Initialize window "newp" from window "old".
1343  * Only the essential things are copied.
1344  */
1345     static void
1346 win_init_some(win_T *newp, win_T *oldp)
1347 {
1348     /* Use the same argument list. */
1349     newp->w_alist = oldp->w_alist;
1350     ++newp->w_alist->al_refcount;
1351     newp->w_arg_idx = oldp->w_arg_idx;
1352 
1353     /* copy options from existing window */
1354     win_copy_options(oldp, newp);
1355 }
1356 
1357 #endif /* FEAT_WINDOWS */
1358 
1359 #if defined(FEAT_WINDOWS) || defined(PROTO)
1360 /*
1361  * Check if "win" is a pointer to an existing window in the current tab page.
1362  */
1363     int
1364 win_valid(win_T *win)
1365 {
1366     win_T	*wp;
1367 
1368     if (win == NULL)
1369 	return FALSE;
1370     FOR_ALL_WINDOWS(wp)
1371 	if (wp == win)
1372 	    return TRUE;
1373     return FALSE;
1374 }
1375 
1376 /*
1377  * Check if "win" is a pointer to an existing window in any tab page.
1378  */
1379     int
1380 win_valid_any_tab(win_T *win)
1381 {
1382     win_T	*wp;
1383     tabpage_T	*tp;
1384 
1385     if (win == NULL)
1386 	return FALSE;
1387     FOR_ALL_TABPAGES(tp)
1388     {
1389 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
1390 	{
1391 	    if (wp == win)
1392 		return TRUE;
1393 	}
1394     }
1395     return FALSE;
1396 }
1397 
1398 /*
1399  * Return the number of windows.
1400  */
1401     int
1402 win_count(void)
1403 {
1404     win_T	*wp;
1405     int		count = 0;
1406 
1407     FOR_ALL_WINDOWS(wp)
1408 	++count;
1409     return count;
1410 }
1411 
1412 /*
1413  * Make "count" windows on the screen.
1414  * Return actual number of windows on the screen.
1415  * Must be called when there is just one window, filling the whole screen
1416  * (excluding the command line).
1417  */
1418     int
1419 make_windows(
1420     int		count,
1421     int		vertical UNUSED)  /* split windows vertically if TRUE */
1422 {
1423     int		maxcount;
1424     int		todo;
1425 
1426     if (vertical)
1427     {
1428 	/* Each windows needs at least 'winminwidth' lines and a separator
1429 	 * column. */
1430 	maxcount = (curwin->w_width + curwin->w_vsep_width
1431 					     - (p_wiw - p_wmw)) / (p_wmw + 1);
1432     }
1433     else
1434     {
1435 	/* Each window needs at least 'winminheight' lines and a status line. */
1436 	maxcount = (curwin->w_height + curwin->w_status_height
1437 				  - (p_wh - p_wmh)) / (p_wmh + STATUS_HEIGHT);
1438     }
1439 
1440     if (maxcount < 2)
1441 	maxcount = 2;
1442     if (count > maxcount)
1443 	count = maxcount;
1444 
1445     /*
1446      * add status line now, otherwise first window will be too big
1447      */
1448     if (count > 1)
1449 	last_status(TRUE);
1450 
1451 #ifdef FEAT_AUTOCMD
1452     /*
1453      * Don't execute autocommands while creating the windows.  Must do that
1454      * when putting the buffers in the windows.
1455      */
1456     block_autocmds();
1457 #endif
1458 
1459     /* todo is number of windows left to create */
1460     for (todo = count - 1; todo > 0; --todo)
1461 	if (vertical)
1462 	{
1463 	    if (win_split(curwin->w_width - (curwin->w_width - todo)
1464 			/ (todo + 1) - 1, WSP_VERT | WSP_ABOVE) == FAIL)
1465 		break;
1466 	}
1467 	else
1468 	{
1469 	    if (win_split(curwin->w_height - (curwin->w_height - todo
1470 			    * STATUS_HEIGHT) / (todo + 1)
1471 			- STATUS_HEIGHT, WSP_ABOVE) == FAIL)
1472 		break;
1473 	}
1474 
1475 #ifdef FEAT_AUTOCMD
1476     unblock_autocmds();
1477 #endif
1478 
1479     /* return actual number of windows */
1480     return (count - todo);
1481 }
1482 
1483 /*
1484  * Exchange current and next window
1485  */
1486     static void
1487 win_exchange(long Prenum)
1488 {
1489     frame_T	*frp;
1490     frame_T	*frp2;
1491     win_T	*wp;
1492     win_T	*wp2;
1493     int		temp;
1494 
1495     if (ONE_WINDOW)	    /* just one window */
1496     {
1497 	beep_flush();
1498 	return;
1499     }
1500 
1501 #ifdef FEAT_GUI
1502     need_mouse_correct = TRUE;
1503 #endif
1504 
1505     /*
1506      * find window to exchange with
1507      */
1508     if (Prenum)
1509     {
1510 	frp = curwin->w_frame->fr_parent->fr_child;
1511 	while (frp != NULL && --Prenum > 0)
1512 	    frp = frp->fr_next;
1513     }
1514     else if (curwin->w_frame->fr_next != NULL)	/* Swap with next */
1515 	frp = curwin->w_frame->fr_next;
1516     else    /* Swap last window in row/col with previous */
1517 	frp = curwin->w_frame->fr_prev;
1518 
1519     /* We can only exchange a window with another window, not with a frame
1520      * containing windows. */
1521     if (frp == NULL || frp->fr_win == NULL || frp->fr_win == curwin)
1522 	return;
1523     wp = frp->fr_win;
1524 
1525 /*
1526  * 1. remove curwin from the list. Remember after which window it was in wp2
1527  * 2. insert curwin before wp in the list
1528  * if wp != wp2
1529  *    3. remove wp from the list
1530  *    4. insert wp after wp2
1531  * 5. exchange the status line height and vsep width.
1532  */
1533     wp2 = curwin->w_prev;
1534     frp2 = curwin->w_frame->fr_prev;
1535     if (wp->w_prev != curwin)
1536     {
1537 	win_remove(curwin, NULL);
1538 	frame_remove(curwin->w_frame);
1539 	win_append(wp->w_prev, curwin);
1540 	frame_insert(frp, curwin->w_frame);
1541     }
1542     if (wp != wp2)
1543     {
1544 	win_remove(wp, NULL);
1545 	frame_remove(wp->w_frame);
1546 	win_append(wp2, wp);
1547 	if (frp2 == NULL)
1548 	    frame_insert(wp->w_frame->fr_parent->fr_child, wp->w_frame);
1549 	else
1550 	    frame_append(frp2, wp->w_frame);
1551     }
1552     temp = curwin->w_status_height;
1553     curwin->w_status_height = wp->w_status_height;
1554     wp->w_status_height = temp;
1555     temp = curwin->w_vsep_width;
1556     curwin->w_vsep_width = wp->w_vsep_width;
1557     wp->w_vsep_width = temp;
1558 
1559     /* If the windows are not in the same frame, exchange the sizes to avoid
1560      * messing up the window layout.  Otherwise fix the frame sizes. */
1561     if (curwin->w_frame->fr_parent != wp->w_frame->fr_parent)
1562     {
1563 	temp = curwin->w_height;
1564 	curwin->w_height = wp->w_height;
1565 	wp->w_height = temp;
1566 	temp = curwin->w_width;
1567 	curwin->w_width = wp->w_width;
1568 	wp->w_width = temp;
1569     }
1570     else
1571     {
1572 	frame_fix_height(curwin);
1573 	frame_fix_height(wp);
1574 	frame_fix_width(curwin);
1575 	frame_fix_width(wp);
1576     }
1577 
1578     (void)win_comp_pos();		/* recompute window positions */
1579 
1580     win_enter(wp, TRUE);
1581     redraw_later(CLEAR);
1582 }
1583 
1584 /*
1585  * rotate windows: if upwards TRUE the second window becomes the first one
1586  *		   if upwards FALSE the first window becomes the second one
1587  */
1588     static void
1589 win_rotate(int upwards, int count)
1590 {
1591     win_T	*wp1;
1592     win_T	*wp2;
1593     frame_T	*frp;
1594     int		n;
1595 
1596     if (ONE_WINDOW)		/* nothing to do */
1597     {
1598 	beep_flush();
1599 	return;
1600     }
1601 
1602 #ifdef FEAT_GUI
1603     need_mouse_correct = TRUE;
1604 #endif
1605 
1606     /* Check if all frames in this row/col have one window. */
1607     for (frp = curwin->w_frame->fr_parent->fr_child; frp != NULL;
1608 							   frp = frp->fr_next)
1609 	if (frp->fr_win == NULL)
1610 	{
1611 	    EMSG(_("E443: Cannot rotate when another window is split"));
1612 	    return;
1613 	}
1614 
1615     while (count--)
1616     {
1617 	if (upwards)		/* first window becomes last window */
1618 	{
1619 	    /* remove first window/frame from the list */
1620 	    frp = curwin->w_frame->fr_parent->fr_child;
1621 	    wp1 = frp->fr_win;
1622 	    win_remove(wp1, NULL);
1623 	    frame_remove(frp);
1624 
1625 	    /* find last frame and append removed window/frame after it */
1626 	    for ( ; frp->fr_next != NULL; frp = frp->fr_next)
1627 		;
1628 	    win_append(frp->fr_win, wp1);
1629 	    frame_append(frp, wp1->w_frame);
1630 
1631 	    wp2 = frp->fr_win;		/* previously last window */
1632 	}
1633 	else			/* last window becomes first window */
1634 	{
1635 	    /* find last window/frame in the list and remove it */
1636 	    for (frp = curwin->w_frame; frp->fr_next != NULL;
1637 							   frp = frp->fr_next)
1638 		;
1639 	    wp1 = frp->fr_win;
1640 	    wp2 = wp1->w_prev;		    /* will become last window */
1641 	    win_remove(wp1, NULL);
1642 	    frame_remove(frp);
1643 
1644 	    /* append the removed window/frame before the first in the list */
1645 	    win_append(frp->fr_parent->fr_child->fr_win->w_prev, wp1);
1646 	    frame_insert(frp->fr_parent->fr_child, frp);
1647 	}
1648 
1649 	/* exchange status height and vsep width of old and new last window */
1650 	n = wp2->w_status_height;
1651 	wp2->w_status_height = wp1->w_status_height;
1652 	wp1->w_status_height = n;
1653 	frame_fix_height(wp1);
1654 	frame_fix_height(wp2);
1655 	n = wp2->w_vsep_width;
1656 	wp2->w_vsep_width = wp1->w_vsep_width;
1657 	wp1->w_vsep_width = n;
1658 	frame_fix_width(wp1);
1659 	frame_fix_width(wp2);
1660 
1661 	/* recompute w_winrow and w_wincol for all windows */
1662 	(void)win_comp_pos();
1663     }
1664 
1665     redraw_later(CLEAR);
1666 }
1667 
1668 /*
1669  * Move the current window to the very top/bottom/left/right of the screen.
1670  */
1671     static void
1672 win_totop(int size, int flags)
1673 {
1674     int		dir;
1675     int		height = curwin->w_height;
1676 
1677     if (ONE_WINDOW)
1678     {
1679 	beep_flush();
1680 	return;
1681     }
1682 
1683     /* Remove the window and frame from the tree of frames. */
1684     (void)winframe_remove(curwin, &dir, NULL);
1685     win_remove(curwin, NULL);
1686     last_status(FALSE);	    /* may need to remove last status line */
1687     (void)win_comp_pos();   /* recompute window positions */
1688 
1689     /* Split a window on the desired side and put the window there. */
1690     (void)win_split_ins(size, flags, curwin, dir);
1691     if (!(flags & WSP_VERT))
1692     {
1693 	win_setheight(height);
1694 	if (p_ea)
1695 	    win_equal(curwin, TRUE, 'v');
1696     }
1697 
1698 #if defined(FEAT_GUI)
1699     /* When 'guioptions' includes 'L' or 'R' may have to remove or add
1700      * scrollbars.  Have to update them anyway. */
1701     gui_may_update_scrollbars();
1702 #endif
1703 }
1704 
1705 /*
1706  * Move window "win1" to below/right of "win2" and make "win1" the current
1707  * window.  Only works within the same frame!
1708  */
1709     void
1710 win_move_after(win_T *win1, win_T *win2)
1711 {
1712     int		height;
1713 
1714     /* check if the arguments are reasonable */
1715     if (win1 == win2)
1716 	return;
1717 
1718     /* check if there is something to do */
1719     if (win2->w_next != win1)
1720     {
1721 	/* may need move the status line/vertical separator of the last window
1722 	 * */
1723 	if (win1 == lastwin)
1724 	{
1725 	    height = win1->w_prev->w_status_height;
1726 	    win1->w_prev->w_status_height = win1->w_status_height;
1727 	    win1->w_status_height = height;
1728 	    if (win1->w_prev->w_vsep_width == 1)
1729 	    {
1730 		/* Remove the vertical separator from the last-but-one window,
1731 		 * add it to the last window.  Adjust the frame widths. */
1732 		win1->w_prev->w_vsep_width = 0;
1733 		win1->w_prev->w_frame->fr_width -= 1;
1734 		win1->w_vsep_width = 1;
1735 		win1->w_frame->fr_width += 1;
1736 	    }
1737 	}
1738 	else if (win2 == lastwin)
1739 	{
1740 	    height = win1->w_status_height;
1741 	    win1->w_status_height = win2->w_status_height;
1742 	    win2->w_status_height = height;
1743 	    if (win1->w_vsep_width == 1)
1744 	    {
1745 		/* Remove the vertical separator from win1, add it to the last
1746 		 * window, win2.  Adjust the frame widths. */
1747 		win2->w_vsep_width = 1;
1748 		win2->w_frame->fr_width += 1;
1749 		win1->w_vsep_width = 0;
1750 		win1->w_frame->fr_width -= 1;
1751 	    }
1752 	}
1753 	win_remove(win1, NULL);
1754 	frame_remove(win1->w_frame);
1755 	win_append(win2, win1);
1756 	frame_append(win2->w_frame, win1->w_frame);
1757 
1758 	(void)win_comp_pos();	/* recompute w_winrow for all windows */
1759 	redraw_later(NOT_VALID);
1760     }
1761     win_enter(win1, FALSE);
1762 }
1763 
1764 /*
1765  * Make all windows the same height.
1766  * 'next_curwin' will soon be the current window, make sure it has enough
1767  * rows.
1768  */
1769     void
1770 win_equal(
1771     win_T	*next_curwin,	/* pointer to current window to be or NULL */
1772     int		current,	/* do only frame with current window */
1773     int		dir)		/* 'v' for vertically, 'h' for horizontally,
1774 				   'b' for both, 0 for using p_ead */
1775 {
1776     if (dir == 0)
1777 	dir = *p_ead;
1778     win_equal_rec(next_curwin == NULL ? curwin : next_curwin, current,
1779 		      topframe, dir, 0, tabline_height(),
1780 					   (int)Columns, topframe->fr_height);
1781 }
1782 
1783 /*
1784  * Set a frame to a new position and height, spreading the available room
1785  * equally over contained frames.
1786  * The window "next_curwin" (if not NULL) should at least get the size from
1787  * 'winheight' and 'winwidth' if possible.
1788  */
1789     static void
1790 win_equal_rec(
1791     win_T	*next_curwin,	/* pointer to current window to be or NULL */
1792     int		current,	/* do only frame with current window */
1793     frame_T	*topfr,		/* frame to set size off */
1794     int		dir,		/* 'v', 'h' or 'b', see win_equal() */
1795     int		col,		/* horizontal position for frame */
1796     int		row,		/* vertical position for frame */
1797     int		width,		/* new width of frame */
1798     int		height)		/* new height of frame */
1799 {
1800     int		n, m;
1801     int		extra_sep = 0;
1802     int		wincount, totwincount = 0;
1803     frame_T	*fr;
1804     int		next_curwin_size = 0;
1805     int		room = 0;
1806     int		new_size;
1807     int		has_next_curwin = 0;
1808     int		hnc;
1809 
1810     if (topfr->fr_layout == FR_LEAF)
1811     {
1812 	/* Set the width/height of this frame.
1813 	 * Redraw when size or position changes */
1814 	if (topfr->fr_height != height || topfr->fr_win->w_winrow != row
1815 		|| topfr->fr_width != width || topfr->fr_win->w_wincol != col
1816 	   )
1817 	{
1818 	    topfr->fr_win->w_winrow = row;
1819 	    frame_new_height(topfr, height, FALSE, FALSE);
1820 	    topfr->fr_win->w_wincol = col;
1821 	    frame_new_width(topfr, width, FALSE, FALSE);
1822 	    redraw_all_later(CLEAR);
1823 	}
1824     }
1825     else if (topfr->fr_layout == FR_ROW)
1826     {
1827 	topfr->fr_width = width;
1828 	topfr->fr_height = height;
1829 
1830 	if (dir != 'v')			/* equalize frame widths */
1831 	{
1832 	    /* Compute the maximum number of windows horizontally in this
1833 	     * frame. */
1834 	    n = frame_minwidth(topfr, NOWIN);
1835 	    /* add one for the rightmost window, it doesn't have a separator */
1836 	    if (col + width == Columns)
1837 		extra_sep = 1;
1838 	    else
1839 		extra_sep = 0;
1840 	    totwincount = (n + extra_sep) / (p_wmw + 1);
1841 	    has_next_curwin = frame_has_win(topfr, next_curwin);
1842 
1843 	    /*
1844 	     * Compute width for "next_curwin" window and room available for
1845 	     * other windows.
1846 	     * "m" is the minimal width when counting p_wiw for "next_curwin".
1847 	     */
1848 	    m = frame_minwidth(topfr, next_curwin);
1849 	    room = width - m;
1850 	    if (room < 0)
1851 	    {
1852 		next_curwin_size = p_wiw + room;
1853 		room = 0;
1854 	    }
1855 	    else
1856 	    {
1857 		next_curwin_size = -1;
1858 		for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
1859 		{
1860 		    /* If 'winfixwidth' set keep the window width if
1861 		     * possible.
1862 		     * Watch out for this window being the next_curwin. */
1863 		    if (frame_fixed_width(fr))
1864 		    {
1865 			n = frame_minwidth(fr, NOWIN);
1866 			new_size = fr->fr_width;
1867 			if (frame_has_win(fr, next_curwin))
1868 			{
1869 			    room += p_wiw - p_wmw;
1870 			    next_curwin_size = 0;
1871 			    if (new_size < p_wiw)
1872 				new_size = p_wiw;
1873 			}
1874 			else
1875 			    /* These windows don't use up room. */
1876 			    totwincount -= (n + (fr->fr_next == NULL
1877 					      ? extra_sep : 0)) / (p_wmw + 1);
1878 			room -= new_size - n;
1879 			if (room < 0)
1880 			{
1881 			    new_size += room;
1882 			    room = 0;
1883 			}
1884 			fr->fr_newwidth = new_size;
1885 		    }
1886 		}
1887 		if (next_curwin_size == -1)
1888 		{
1889 		    if (!has_next_curwin)
1890 			next_curwin_size = 0;
1891 		    else if (totwincount > 1
1892 			    && (room + (totwincount - 2))
1893 						  / (totwincount - 1) > p_wiw)
1894 		    {
1895 			/* Can make all windows wider than 'winwidth', spread
1896 			 * the room equally. */
1897 			next_curwin_size = (room + p_wiw
1898 					    + (totwincount - 1) * p_wmw
1899 					    + (totwincount - 1)) / totwincount;
1900 			room -= next_curwin_size - p_wiw;
1901 		    }
1902 		    else
1903 			next_curwin_size = p_wiw;
1904 		}
1905 	    }
1906 
1907 	    if (has_next_curwin)
1908 		--totwincount;		/* don't count curwin */
1909 	}
1910 
1911 	for (fr = topfr->fr_child; fr != NULL; fr = fr->fr_next)
1912 	{
1913 	    n = m = 0;
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 	    n = m = 0;
2056 	    wincount = 1;
2057 	    if (fr->fr_next == NULL)
2058 		/* last frame gets all that remains (avoid roundoff error) */
2059 		new_size = height;
2060 	    else if (dir == 'h')
2061 		new_size = fr->fr_height;
2062 	    else if (frame_fixed_height(fr))
2063 	    {
2064 		new_size = fr->fr_newheight;
2065 		wincount = 0;	    /* doesn't count as a sizeable window */
2066 	    }
2067 	    else
2068 	    {
2069 		/* Compute the maximum number of windows vert. in "fr". */
2070 		n = frame_minheight(fr, NOWIN);
2071 		wincount = (n + (fr->fr_next == NULL ? extra_sep : 0))
2072 								/ (p_wmh + 1);
2073 		m = frame_minheight(fr, next_curwin);
2074 		if (has_next_curwin)
2075 		    hnc = frame_has_win(fr, next_curwin);
2076 		else
2077 		    hnc = FALSE;
2078 		if (hnc)	    /* don't count next_curwin */
2079 		    --wincount;
2080 		if (totwincount == 0)
2081 		    new_size = room;
2082 		else
2083 		    new_size = (wincount * room + ((unsigned)totwincount >> 1))
2084 								/ totwincount;
2085 		if (hnc)	    /* add next_curwin size */
2086 		{
2087 		    next_curwin_size -= p_wh - (m - n);
2088 		    new_size += next_curwin_size;
2089 		    room -= new_size - next_curwin_size;
2090 		}
2091 		else
2092 		    room -= new_size;
2093 		new_size += n;
2094 	    }
2095 	    /* Skip frame that is full width when splitting or closing a
2096 	     * window, unless equalizing all frames. */
2097 	    if (!current || dir != 'h' || topfr->fr_parent != NULL
2098 		    || (new_size != fr->fr_height)
2099 		    || frame_has_win(fr, next_curwin))
2100 		win_equal_rec(next_curwin, current, fr, dir, col, row,
2101 							     width, new_size);
2102 	    row += new_size;
2103 	    height -= new_size;
2104 	    totwincount -= wincount;
2105 	}
2106     }
2107 }
2108 
2109 /*
2110  * Close all windows for buffer "buf".
2111  */
2112     void
2113 close_windows(
2114     buf_T	*buf,
2115     int		keep_curwin)	    /* don't close "curwin" */
2116 {
2117     win_T	*wp;
2118     tabpage_T   *tp, *nexttp;
2119     int		h = tabline_height();
2120 #ifdef FEAT_AUTOCMD
2121     int		count = tabpage_index(NULL);
2122 #endif
2123 
2124     ++RedrawingDisabled;
2125 
2126     for (wp = firstwin; wp != NULL && !ONE_WINDOW; )
2127     {
2128 	if (wp->w_buffer == buf && (!keep_curwin || wp != curwin)
2129 #ifdef FEAT_AUTOCMD
2130 		&& !(wp->w_closing || wp->w_buffer->b_locked > 0)
2131 #endif
2132 		)
2133 	{
2134 	    if (win_close(wp, FALSE) == FAIL)
2135 		/* If closing the window fails give up, to avoid looping
2136 		 * forever. */
2137 		break;
2138 
2139 	    /* Start all over, autocommands may change the window layout. */
2140 	    wp = firstwin;
2141 	}
2142 	else
2143 	    wp = wp->w_next;
2144     }
2145 
2146     /* Also check windows in other tab pages. */
2147     for (tp = first_tabpage; tp != NULL; tp = nexttp)
2148     {
2149 	nexttp = tp->tp_next;
2150 	if (tp != curtab)
2151 	    for (wp = tp->tp_firstwin; wp != NULL; wp = wp->w_next)
2152 		if (wp->w_buffer == buf
2153 #ifdef FEAT_AUTOCMD
2154 		    && !(wp->w_closing || wp->w_buffer->b_locked > 0)
2155 #endif
2156 		    )
2157 		{
2158 		    win_close_othertab(wp, FALSE, tp);
2159 
2160 		    /* Start all over, the tab page may be closed and
2161 		     * autocommands may change the window layout. */
2162 		    nexttp = first_tabpage;
2163 		    break;
2164 		}
2165     }
2166 
2167     --RedrawingDisabled;
2168 
2169 #ifdef FEAT_AUTOCMD
2170     if (count != tabpage_index(NULL))
2171 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2172 #endif
2173 
2174     redraw_tabline = TRUE;
2175     if (h != tabline_height())
2176 	shell_new_rows();
2177 }
2178 
2179 /*
2180  * Return TRUE if the current window is the only window that exists (ignoring
2181  * "aucmd_win").
2182  * Returns FALSE if there is a window, possibly in another tab page.
2183  */
2184     static int
2185 last_window(void)
2186 {
2187     return (one_window() && first_tabpage->tp_next == NULL);
2188 }
2189 
2190 /*
2191  * Return TRUE if there is only one window other than "aucmd_win" in the
2192  * current tab page.
2193  */
2194     int
2195 one_window(void)
2196 {
2197 #ifdef FEAT_AUTOCMD
2198     win_T	*wp;
2199     int		seen_one = FALSE;
2200 
2201     FOR_ALL_WINDOWS(wp)
2202     {
2203 	if (wp != aucmd_win)
2204 	{
2205 	    if (seen_one)
2206 		return FALSE;
2207 	    seen_one = TRUE;
2208 	}
2209     }
2210     return TRUE;
2211 #else
2212     return ONE_WINDOW;
2213 #endif
2214 }
2215 
2216 /*
2217  * Close the possibly last window in a tab page.
2218  * Returns TRUE when the window was closed already.
2219  */
2220     static int
2221 close_last_window_tabpage(
2222     win_T	*win,
2223     int		free_buf,
2224     tabpage_T   *prev_curtab)
2225 {
2226     if (ONE_WINDOW)
2227     {
2228 #ifdef FEAT_AUTOCMD
2229 	buf_T	*old_curbuf = curbuf;
2230 #endif
2231 
2232 	/*
2233 	 * Closing the last window in a tab page.  First go to another tab
2234 	 * page and then close the window and the tab page.  This avoids that
2235 	 * curwin and curtab are invalid while we are freeing memory, they may
2236 	 * be used in GUI events.
2237 	 * Don't trigger autocommands yet, they may use wrong values, so do
2238 	 * that below.
2239 	 */
2240 	goto_tabpage_tp(alt_tabpage(), FALSE, TRUE);
2241 	redraw_tabline = TRUE;
2242 
2243 	/* Safety check: Autocommands may have closed the window when jumping
2244 	 * to the other tab page. */
2245 	if (valid_tabpage(prev_curtab) && prev_curtab->tp_firstwin == win)
2246 	{
2247 	    int	    h = tabline_height();
2248 
2249 	    win_close_othertab(win, free_buf, prev_curtab);
2250 	    if (h != tabline_height())
2251 		shell_new_rows();
2252 	}
2253 	/* Since goto_tabpage_tp above did not trigger *Enter autocommands, do
2254 	 * that now. */
2255 #ifdef FEAT_AUTOCMD
2256 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);
2257 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
2258 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
2259 	if (old_curbuf != curbuf)
2260 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2261 #endif
2262 	return TRUE;
2263     }
2264     return FALSE;
2265 }
2266 
2267 /*
2268  * Close window "win".  Only works for the current tab page.
2269  * If "free_buf" is TRUE related buffer may be unloaded.
2270  *
2271  * Called by :quit, :close, :xit, :wq and findtag().
2272  * Returns FAIL when the window was not closed.
2273  */
2274     int
2275 win_close(win_T *win, int free_buf)
2276 {
2277     win_T	*wp;
2278 #ifdef FEAT_AUTOCMD
2279     int		other_buffer = FALSE;
2280 #endif
2281     int		close_curwin = FALSE;
2282     int		dir;
2283     int		help_window = FALSE;
2284     tabpage_T   *prev_curtab = curtab;
2285 
2286     if (last_window())
2287     {
2288 	EMSG(_("E444: Cannot close last window"));
2289 	return FAIL;
2290     }
2291 
2292 #ifdef FEAT_AUTOCMD
2293     if (win->w_closing || (win->w_buffer != NULL
2294 					       && win->w_buffer->b_locked > 0))
2295 	return FAIL; /* window is already being closed */
2296     if (win == aucmd_win)
2297     {
2298 	EMSG(_("E813: Cannot close autocmd window"));
2299 	return FAIL;
2300     }
2301     if ((firstwin == aucmd_win || lastwin == aucmd_win) && one_window())
2302     {
2303 	EMSG(_("E814: Cannot close window, only autocmd window would remain"));
2304 	return FAIL;
2305     }
2306 #endif
2307 
2308     /* When closing the last window in a tab page first go to another tab page
2309      * and then close the window and the tab page to avoid that curwin and
2310      * curtab are invalid while we are freeing memory. */
2311     if (close_last_window_tabpage(win, free_buf, prev_curtab))
2312       return FAIL;
2313 
2314     /* When closing the help window, try restoring a snapshot after closing
2315      * the window.  Otherwise clear the snapshot, it's now invalid. */
2316     if (win->w_buffer != NULL && win->w_buffer->b_help)
2317 	help_window = TRUE;
2318     else
2319 	clear_snapshot(curtab, SNAP_HELP_IDX);
2320 
2321 #ifdef FEAT_AUTOCMD
2322     if (win == curwin)
2323     {
2324 	/*
2325 	 * Guess which window is going to be the new current window.
2326 	 * This may change because of the autocommands (sigh).
2327 	 */
2328 	wp = frame2win(win_altframe(win, NULL));
2329 
2330 	/*
2331 	 * Be careful: If autocommands delete the window or cause this window
2332 	 * to be the last one left, return now.
2333 	 */
2334 	if (wp->w_buffer != curbuf)
2335 	{
2336 	    other_buffer = TRUE;
2337 	    win->w_closing = TRUE;
2338 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
2339 	    if (!win_valid(win))
2340 		return FAIL;
2341 	    win->w_closing = FALSE;
2342 	    if (last_window())
2343 		return FAIL;
2344 	}
2345 	win->w_closing = TRUE;
2346 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
2347 	if (!win_valid(win))
2348 	    return FAIL;
2349 	win->w_closing = FALSE;
2350 	if (last_window())
2351 	    return FAIL;
2352 # ifdef FEAT_EVAL
2353 	/* autocmds may abort script processing */
2354 	if (aborting())
2355 	    return FAIL;
2356 # endif
2357     }
2358 #endif
2359 
2360 #ifdef FEAT_GUI
2361     /* Avoid trouble with scrollbars that are going to be deleted in
2362      * win_free(). */
2363     if (gui.in_use)
2364 	out_flush();
2365 #endif
2366 
2367 #ifdef FEAT_SYN_HL
2368     /* Free independent synblock before the buffer is freed. */
2369     if (win->w_buffer != NULL)
2370 	reset_synblock(win);
2371 #endif
2372 
2373     /*
2374      * Close the link to the buffer.
2375      */
2376     if (win->w_buffer != NULL)
2377     {
2378 	bufref_T    bufref;
2379 
2380 	set_bufref(&bufref, curbuf);
2381 #ifdef FEAT_AUTOCMD
2382 	win->w_closing = TRUE;
2383 #endif
2384 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0, TRUE);
2385 #ifdef FEAT_AUTOCMD
2386 	if (win_valid_any_tab(win))
2387 	    win->w_closing = FALSE;
2388 #endif
2389 	/* Make sure curbuf is valid. It can become invalid if 'bufhidden' is
2390 	 * "wipe". */
2391 	if (!bufref_valid(&bufref))
2392 	    curbuf = firstbuf;
2393     }
2394 
2395     if (only_one_window() && win_valid(win) && win->w_buffer == NULL
2396 	    && (last_window() || curtab != prev_curtab
2397 		|| close_last_window_tabpage(win, free_buf, prev_curtab)))
2398     {
2399 	/* Autocommands have close all windows, quit now.  Restore
2400 	 * curwin->w_buffer, otherwise writing viminfo may fail. */
2401 	if (curwin->w_buffer == NULL)
2402 	    curwin->w_buffer = curbuf;
2403 	getout(0);
2404     }
2405 
2406     /* Autocommands may have moved to another tab page. */
2407     if (curtab != prev_curtab && win_valid_any_tab(win)
2408 						      && win->w_buffer == NULL)
2409     {
2410 	/* Need to close the window anyway, since the buffer is NULL. */
2411 	win_close_othertab(win, FALSE, prev_curtab);
2412 	return FAIL;
2413     }
2414 
2415     /* Autocommands may have closed the window already or closed the only
2416      * other window. */
2417     if (!win_valid(win) || last_window()
2418 	    || close_last_window_tabpage(win, free_buf, prev_curtab))
2419 	return FAIL;
2420 
2421     /* Free the memory used for the window and get the window that received
2422      * the screen space. */
2423     wp = win_free_mem(win, &dir, NULL);
2424 
2425     /* Make sure curwin isn't invalid.  It can cause severe trouble when
2426      * printing an error message.  For win_equal() curbuf needs to be valid
2427      * too. */
2428     if (win == curwin)
2429     {
2430 	curwin = wp;
2431 #ifdef FEAT_QUICKFIX
2432 	if (wp->w_p_pvw || bt_quickfix(wp->w_buffer))
2433 	{
2434 	    /*
2435 	     * If the cursor goes to the preview or the quickfix window, try
2436 	     * finding another window to go to.
2437 	     */
2438 	    for (;;)
2439 	    {
2440 		if (wp->w_next == NULL)
2441 		    wp = firstwin;
2442 		else
2443 		    wp = wp->w_next;
2444 		if (wp == curwin)
2445 		    break;
2446 		if (!wp->w_p_pvw && !bt_quickfix(wp->w_buffer))
2447 		{
2448 		    curwin = wp;
2449 		    break;
2450 		}
2451 	    }
2452 	}
2453 #endif
2454 	curbuf = curwin->w_buffer;
2455 	close_curwin = TRUE;
2456 
2457 	/* The cursor position may be invalid if the buffer changed after last
2458 	 * using the window. */
2459 	check_cursor();
2460     }
2461     if (p_ea && (*p_ead == 'b' || *p_ead == dir))
2462 	win_equal(curwin, TRUE, dir);
2463     else
2464 	win_comp_pos();
2465     if (close_curwin)
2466     {
2467 	win_enter_ext(wp, FALSE, TRUE, FALSE, TRUE, TRUE);
2468 #ifdef FEAT_AUTOCMD
2469 	if (other_buffer)
2470 	    /* careful: after this wp and win may be invalid! */
2471 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2472 #endif
2473     }
2474 
2475     /*
2476      * If last window has a status line now and we don't want one,
2477      * remove the status line.
2478      */
2479     last_status(FALSE);
2480 
2481     /* After closing the help window, try restoring the window layout from
2482      * before it was opened. */
2483     if (help_window)
2484 	restore_snapshot(SNAP_HELP_IDX, close_curwin);
2485 
2486 #if defined(FEAT_GUI)
2487     /* When 'guioptions' includes 'L' or 'R' may have to remove scrollbars. */
2488     if (gui.in_use && !win_hasvertsplit())
2489 	gui_init_which_components(NULL);
2490 #endif
2491 
2492     redraw_all_later(NOT_VALID);
2493     return OK;
2494 }
2495 
2496 /*
2497  * Close window "win" in tab page "tp", which is not the current tab page.
2498  * This may be the last window in that tab page and result in closing the tab,
2499  * thus "tp" may become invalid!
2500  * Caller must check if buffer is hidden and whether the tabline needs to be
2501  * updated.
2502  */
2503     void
2504 win_close_othertab(win_T *win, int free_buf, tabpage_T *tp)
2505 {
2506     win_T	*wp;
2507     int		dir;
2508     tabpage_T   *ptp = NULL;
2509     int		free_tp = FALSE;
2510 
2511 #ifdef FEAT_AUTOCMD
2512     /* Get here with win->w_buffer == NULL when win_close() detects the tab
2513      * page changed. */
2514     if (win->w_closing || (win->w_buffer != NULL
2515 					       && win->w_buffer->b_locked > 0))
2516 	return; /* window is already being closed */
2517 #endif
2518 
2519     if (win->w_buffer != NULL)
2520 	/* Close the link to the buffer. */
2521 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0, FALSE);
2522 
2523     /* Careful: Autocommands may have closed the tab page or made it the
2524      * current tab page.  */
2525     for (ptp = first_tabpage; ptp != NULL && ptp != tp; ptp = ptp->tp_next)
2526 	;
2527     if (ptp == NULL || tp == curtab)
2528 	return;
2529 
2530     /* Autocommands may have closed the window already. */
2531     for (wp = tp->tp_firstwin; wp != NULL && wp != win; wp = wp->w_next)
2532 	;
2533     if (wp == NULL)
2534 	return;
2535 
2536     /* When closing the last window in a tab page remove the tab page. */
2537     if (tp->tp_firstwin == tp->tp_lastwin)
2538     {
2539 	if (tp == first_tabpage)
2540 	    first_tabpage = tp->tp_next;
2541 	else
2542 	{
2543 	    for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tp;
2544 							   ptp = ptp->tp_next)
2545 		;
2546 	    if (ptp == NULL)
2547 	    {
2548 		internal_error("win_close_othertab()");
2549 		return;
2550 	    }
2551 	    ptp->tp_next = tp->tp_next;
2552 	}
2553 	free_tp = TRUE;
2554     }
2555 
2556     /* Free the memory used for the window. */
2557     win_free_mem(win, &dir, tp);
2558 
2559     if (free_tp)
2560 	free_tabpage(tp);
2561 }
2562 
2563 /*
2564  * Free the memory used for a window.
2565  * Returns a pointer to the window that got the freed up space.
2566  */
2567     static win_T *
2568 win_free_mem(
2569     win_T	*win,
2570     int		*dirp,		/* set to 'v' or 'h' for direction if 'ea' */
2571     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2572 {
2573     frame_T	*frp;
2574     win_T	*wp;
2575 
2576     /* Remove the window and its frame from the tree of frames. */
2577     frp = win->w_frame;
2578     wp = winframe_remove(win, dirp, tp);
2579     vim_free(frp);
2580     win_free(win, tp);
2581 
2582     /* When deleting the current window of another tab page select a new
2583      * current window. */
2584     if (tp != NULL && win == tp->tp_curwin)
2585 	tp->tp_curwin = wp;
2586 
2587     return wp;
2588 }
2589 
2590 #if defined(EXITFREE) || defined(PROTO)
2591     void
2592 win_free_all(void)
2593 {
2594     int		dummy;
2595 
2596 # ifdef FEAT_WINDOWS
2597     while (first_tabpage->tp_next != NULL)
2598 	tabpage_close(TRUE);
2599 # endif
2600 
2601 # ifdef FEAT_AUTOCMD
2602     if (aucmd_win != NULL)
2603     {
2604 	(void)win_free_mem(aucmd_win, &dummy, NULL);
2605 	aucmd_win = NULL;
2606     }
2607 # endif
2608 
2609     while (firstwin != NULL)
2610 	(void)win_free_mem(firstwin, &dummy, NULL);
2611 
2612     /* No window should be used after this. Set curwin to NULL to crash
2613      * instead of using freed memory. */
2614     curwin = NULL;
2615 }
2616 #endif
2617 
2618 /*
2619  * Remove a window and its frame from the tree of frames.
2620  * Returns a pointer to the window that got the freed up space.
2621  */
2622     win_T *
2623 winframe_remove(
2624     win_T	*win,
2625     int		*dirp UNUSED,	/* set to 'v' or 'h' for direction if 'ea' */
2626     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2627 {
2628     frame_T	*frp, *frp2, *frp3;
2629     frame_T	*frp_close = win->w_frame;
2630     win_T	*wp;
2631 
2632     /*
2633      * If there is only one window there is nothing to remove.
2634      */
2635     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2636 	return NULL;
2637 
2638     /*
2639      * Remove the window from its frame.
2640      */
2641     frp2 = win_altframe(win, tp);
2642     wp = frame2win(frp2);
2643 
2644     /* Remove this frame from the list of frames. */
2645     frame_remove(frp_close);
2646 
2647     if (frp_close->fr_parent->fr_layout == FR_COL)
2648     {
2649 	/* When 'winfixheight' is set, try to find another frame in the column
2650 	 * (as close to the closed frame as possible) to distribute the height
2651 	 * to. */
2652 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfh)
2653 	{
2654 	    frp = frp_close->fr_prev;
2655 	    frp3 = frp_close->fr_next;
2656 	    while (frp != NULL || frp3 != NULL)
2657 	    {
2658 		if (frp != NULL)
2659 		{
2660 		    if (frp->fr_win != NULL && !frp->fr_win->w_p_wfh)
2661 		    {
2662 			frp2 = frp;
2663 			wp = frp->fr_win;
2664 			break;
2665 		    }
2666 		    frp = frp->fr_prev;
2667 		}
2668 		if (frp3 != NULL)
2669 		{
2670 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfh)
2671 		    {
2672 			frp2 = frp3;
2673 			wp = frp3->fr_win;
2674 			break;
2675 		    }
2676 		    frp3 = frp3->fr_next;
2677 		}
2678 	    }
2679 	}
2680 	frame_new_height(frp2, frp2->fr_height + frp_close->fr_height,
2681 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2682 	*dirp = 'v';
2683     }
2684     else
2685     {
2686 	/* When 'winfixwidth' is set, try to find another frame in the column
2687 	 * (as close to the closed frame as possible) to distribute the width
2688 	 * to. */
2689 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfw)
2690 	{
2691 	    frp = frp_close->fr_prev;
2692 	    frp3 = frp_close->fr_next;
2693 	    while (frp != NULL || frp3 != NULL)
2694 	    {
2695 		if (frp != NULL)
2696 		{
2697 		    if (frp->fr_win != NULL && !frp->fr_win->w_p_wfw)
2698 		    {
2699 			frp2 = frp;
2700 			wp = frp->fr_win;
2701 			break;
2702 		    }
2703 		    frp = frp->fr_prev;
2704 		}
2705 		if (frp3 != NULL)
2706 		{
2707 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfw)
2708 		    {
2709 			frp2 = frp3;
2710 			wp = frp3->fr_win;
2711 			break;
2712 		    }
2713 		    frp3 = frp3->fr_next;
2714 		}
2715 	    }
2716 	}
2717 	frame_new_width(frp2, frp2->fr_width + frp_close->fr_width,
2718 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2719 	*dirp = 'h';
2720     }
2721 
2722     /* If rows/columns go to a window below/right its positions need to be
2723      * updated.  Can only be done after the sizes have been updated. */
2724     if (frp2 == frp_close->fr_next)
2725     {
2726 	int row = win->w_winrow;
2727 	int col = W_WINCOL(win);
2728 
2729 	frame_comp_pos(frp2, &row, &col);
2730     }
2731 
2732     if (frp2->fr_next == NULL && frp2->fr_prev == NULL)
2733     {
2734 	/* There is no other frame in this list, move its info to the parent
2735 	 * and remove it. */
2736 	frp2->fr_parent->fr_layout = frp2->fr_layout;
2737 	frp2->fr_parent->fr_child = frp2->fr_child;
2738 	for (frp = frp2->fr_child; frp != NULL; frp = frp->fr_next)
2739 	    frp->fr_parent = frp2->fr_parent;
2740 	frp2->fr_parent->fr_win = frp2->fr_win;
2741 	if (frp2->fr_win != NULL)
2742 	    frp2->fr_win->w_frame = frp2->fr_parent;
2743 	frp = frp2->fr_parent;
2744 	vim_free(frp2);
2745 
2746 	frp2 = frp->fr_parent;
2747 	if (frp2 != NULL && frp2->fr_layout == frp->fr_layout)
2748 	{
2749 	    /* The frame above the parent has the same layout, have to merge
2750 	     * the frames into this list. */
2751 	    if (frp2->fr_child == frp)
2752 		frp2->fr_child = frp->fr_child;
2753 	    frp->fr_child->fr_prev = frp->fr_prev;
2754 	    if (frp->fr_prev != NULL)
2755 		frp->fr_prev->fr_next = frp->fr_child;
2756 	    for (frp3 = frp->fr_child; ; frp3 = frp3->fr_next)
2757 	    {
2758 		frp3->fr_parent = frp2;
2759 		if (frp3->fr_next == NULL)
2760 		{
2761 		    frp3->fr_next = frp->fr_next;
2762 		    if (frp->fr_next != NULL)
2763 			frp->fr_next->fr_prev = frp3;
2764 		    break;
2765 		}
2766 	    }
2767 	    vim_free(frp);
2768 	}
2769     }
2770 
2771     return wp;
2772 }
2773 
2774 /*
2775  * Find out which frame is going to get the freed up space when "win" is
2776  * closed.
2777  * if 'splitbelow'/'splitleft' the space goes to the window above/left.
2778  * if 'nosplitbelow'/'nosplitleft' the space goes to the window below/right.
2779  * This makes opening a window and closing it immediately keep the same window
2780  * layout.
2781  */
2782     static frame_T *
2783 win_altframe(
2784     win_T	*win,
2785     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2786 {
2787     frame_T	*frp;
2788     int		b;
2789 
2790     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2791 	/* Last window in this tab page, will go to next tab page. */
2792 	return alt_tabpage()->tp_curwin->w_frame;
2793 
2794     frp = win->w_frame;
2795     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW)
2796 	b = p_spr;
2797     else
2798 	b = p_sb;
2799     if ((!b && frp->fr_next != NULL) || frp->fr_prev == NULL)
2800 	return frp->fr_next;
2801     return frp->fr_prev;
2802 }
2803 
2804 /*
2805  * Return the tabpage that will be used if the current one is closed.
2806  */
2807     static tabpage_T *
2808 alt_tabpage(void)
2809 {
2810     tabpage_T	*tp;
2811 
2812     /* Use the next tab page if possible. */
2813     if (curtab->tp_next != NULL)
2814 	return curtab->tp_next;
2815 
2816     /* Find the last but one tab page. */
2817     for (tp = first_tabpage; tp->tp_next != curtab; tp = tp->tp_next)
2818 	;
2819     return tp;
2820 }
2821 
2822 /*
2823  * Find the left-upper window in frame "frp".
2824  */
2825     static win_T *
2826 frame2win(frame_T *frp)
2827 {
2828     while (frp->fr_win == NULL)
2829 	frp = frp->fr_child;
2830     return frp->fr_win;
2831 }
2832 
2833 /*
2834  * Return TRUE if frame "frp" contains window "wp".
2835  */
2836     static int
2837 frame_has_win(frame_T *frp, win_T *wp)
2838 {
2839     frame_T	*p;
2840 
2841     if (frp->fr_layout == FR_LEAF)
2842 	return frp->fr_win == wp;
2843 
2844     for (p = frp->fr_child; p != NULL; p = p->fr_next)
2845 	if (frame_has_win(p, wp))
2846 	    return TRUE;
2847     return FALSE;
2848 }
2849 
2850 /*
2851  * Set a new height for a frame.  Recursively sets the height for contained
2852  * frames and windows.  Caller must take care of positions.
2853  */
2854     static void
2855 frame_new_height(
2856     frame_T	*topfrp,
2857     int		height,
2858     int		topfirst,	/* resize topmost contained frame first */
2859     int		wfh)		/* obey 'winfixheight' when there is a choice;
2860 				   may cause the height not to be set */
2861 {
2862     frame_T	*frp;
2863     int		extra_lines;
2864     int		h;
2865 
2866     if (topfrp->fr_win != NULL)
2867     {
2868 	/* Simple case: just one window. */
2869 	win_new_height(topfrp->fr_win,
2870 				    height - topfrp->fr_win->w_status_height);
2871     }
2872     else if (topfrp->fr_layout == FR_ROW)
2873     {
2874 	do
2875 	{
2876 	    /* All frames in this row get the same new height. */
2877 	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
2878 	    {
2879 		frame_new_height(frp, height, topfirst, wfh);
2880 		if (frp->fr_height > height)
2881 		{
2882 		    /* Could not fit the windows, make the whole row higher. */
2883 		    height = frp->fr_height;
2884 		    break;
2885 		}
2886 	    }
2887 	}
2888 	while (frp != NULL);
2889     }
2890     else    /* fr_layout == FR_COL */
2891     {
2892 	/* Complicated case: Resize a column of frames.  Resize the bottom
2893 	 * frame first, frames above that when needed. */
2894 
2895 	frp = topfrp->fr_child;
2896 	if (wfh)
2897 	    /* Advance past frames with one window with 'wfh' set. */
2898 	    while (frame_fixed_height(frp))
2899 	    {
2900 		frp = frp->fr_next;
2901 		if (frp == NULL)
2902 		    return;	    /* no frame without 'wfh', give up */
2903 	    }
2904 	if (!topfirst)
2905 	{
2906 	    /* Find the bottom frame of this column */
2907 	    while (frp->fr_next != NULL)
2908 		frp = frp->fr_next;
2909 	    if (wfh)
2910 		/* Advance back for frames with one window with 'wfh' set. */
2911 		while (frame_fixed_height(frp))
2912 		    frp = frp->fr_prev;
2913 	}
2914 
2915 	extra_lines = height - topfrp->fr_height;
2916 	if (extra_lines < 0)
2917 	{
2918 	    /* reduce height of contained frames, bottom or top frame first */
2919 	    while (frp != NULL)
2920 	    {
2921 		h = frame_minheight(frp, NULL);
2922 		if (frp->fr_height + extra_lines < h)
2923 		{
2924 		    extra_lines += frp->fr_height - h;
2925 		    frame_new_height(frp, h, topfirst, wfh);
2926 		}
2927 		else
2928 		{
2929 		    frame_new_height(frp, frp->fr_height + extra_lines,
2930 							       topfirst, wfh);
2931 		    break;
2932 		}
2933 		if (topfirst)
2934 		{
2935 		    do
2936 			frp = frp->fr_next;
2937 		    while (wfh && frp != NULL && frame_fixed_height(frp));
2938 		}
2939 		else
2940 		{
2941 		    do
2942 			frp = frp->fr_prev;
2943 		    while (wfh && frp != NULL && frame_fixed_height(frp));
2944 		}
2945 		/* Increase "height" if we could not reduce enough frames. */
2946 		if (frp == NULL)
2947 		    height -= extra_lines;
2948 	    }
2949 	}
2950 	else if (extra_lines > 0)
2951 	{
2952 	    /* increase height of bottom or top frame */
2953 	    frame_new_height(frp, frp->fr_height + extra_lines, topfirst, wfh);
2954 	}
2955     }
2956     topfrp->fr_height = height;
2957 }
2958 
2959 /*
2960  * Return TRUE if height of frame "frp" should not be changed because of
2961  * the 'winfixheight' option.
2962  */
2963     static int
2964 frame_fixed_height(frame_T *frp)
2965 {
2966     /* frame with one window: fixed height if 'winfixheight' set. */
2967     if (frp->fr_win != NULL)
2968 	return frp->fr_win->w_p_wfh;
2969 
2970     if (frp->fr_layout == FR_ROW)
2971     {
2972 	/* The frame is fixed height if one of the frames in the row is fixed
2973 	 * height. */
2974 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
2975 	    if (frame_fixed_height(frp))
2976 		return TRUE;
2977 	return FALSE;
2978     }
2979 
2980     /* frp->fr_layout == FR_COL: The frame is fixed height if all of the
2981      * frames in the row are fixed height. */
2982     for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
2983 	if (!frame_fixed_height(frp))
2984 	    return FALSE;
2985     return TRUE;
2986 }
2987 
2988 /*
2989  * Return TRUE if width of frame "frp" should not be changed because of
2990  * the 'winfixwidth' option.
2991  */
2992     static int
2993 frame_fixed_width(frame_T *frp)
2994 {
2995     /* frame with one window: fixed width if 'winfixwidth' set. */
2996     if (frp->fr_win != NULL)
2997 	return frp->fr_win->w_p_wfw;
2998 
2999     if (frp->fr_layout == FR_COL)
3000     {
3001 	/* The frame is fixed width if one of the frames in the row is fixed
3002 	 * width. */
3003 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3004 	    if (frame_fixed_width(frp))
3005 		return TRUE;
3006 	return FALSE;
3007     }
3008 
3009     /* frp->fr_layout == FR_ROW: The frame is fixed width if all of the
3010      * frames in the row are fixed width. */
3011     for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3012 	if (!frame_fixed_width(frp))
3013 	    return FALSE;
3014     return TRUE;
3015 }
3016 
3017 /*
3018  * Add a status line to windows at the bottom of "frp".
3019  * Note: Does not check if there is room!
3020  */
3021     static void
3022 frame_add_statusline(frame_T *frp)
3023 {
3024     win_T	*wp;
3025 
3026     if (frp->fr_layout == FR_LEAF)
3027     {
3028 	wp = frp->fr_win;
3029 	if (wp->w_status_height == 0)
3030 	{
3031 	    if (wp->w_height > 0)	/* don't make it negative */
3032 		--wp->w_height;
3033 	    wp->w_status_height = STATUS_HEIGHT;
3034 	}
3035     }
3036     else if (frp->fr_layout == FR_ROW)
3037     {
3038 	/* Handle all the frames in the row. */
3039 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3040 	    frame_add_statusline(frp);
3041     }
3042     else /* frp->fr_layout == FR_COL */
3043     {
3044 	/* Only need to handle the last frame in the column. */
3045 	for (frp = frp->fr_child; frp->fr_next != NULL; frp = frp->fr_next)
3046 	    ;
3047 	frame_add_statusline(frp);
3048     }
3049 }
3050 
3051 /*
3052  * Set width of a frame.  Handles recursively going through contained frames.
3053  * May remove separator line for windows at the right side (for win_close()).
3054  */
3055     static void
3056 frame_new_width(
3057     frame_T	*topfrp,
3058     int		width,
3059     int		leftfirst,	/* resize leftmost contained frame first */
3060     int		wfw)		/* obey 'winfixwidth' when there is a choice;
3061 				   may cause the width not to be set */
3062 {
3063     frame_T	*frp;
3064     int		extra_cols;
3065     int		w;
3066     win_T	*wp;
3067 
3068     if (topfrp->fr_layout == FR_LEAF)
3069     {
3070 	/* Simple case: just one window. */
3071 	wp = topfrp->fr_win;
3072 	/* Find out if there are any windows right of this one. */
3073 	for (frp = topfrp; frp->fr_parent != NULL; frp = frp->fr_parent)
3074 	    if (frp->fr_parent->fr_layout == FR_ROW && frp->fr_next != NULL)
3075 		break;
3076 	if (frp->fr_parent == NULL)
3077 	    wp->w_vsep_width = 0;
3078 	win_new_width(wp, width - wp->w_vsep_width);
3079     }
3080     else if (topfrp->fr_layout == FR_COL)
3081     {
3082 	do
3083 	{
3084 	    /* All frames in this column get the same new width. */
3085 	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3086 	    {
3087 		frame_new_width(frp, width, leftfirst, wfw);
3088 		if (frp->fr_width > width)
3089 		{
3090 		    /* Could not fit the windows, make whole column wider. */
3091 		    width = frp->fr_width;
3092 		    break;
3093 		}
3094 	    }
3095 	} while (frp != NULL);
3096     }
3097     else    /* fr_layout == FR_ROW */
3098     {
3099 	/* Complicated case: Resize a row of frames.  Resize the rightmost
3100 	 * frame first, frames left of it when needed. */
3101 
3102 	frp = topfrp->fr_child;
3103 	if (wfw)
3104 	    /* Advance past frames with one window with 'wfw' set. */
3105 	    while (frame_fixed_width(frp))
3106 	    {
3107 		frp = frp->fr_next;
3108 		if (frp == NULL)
3109 		    return;	    /* no frame without 'wfw', give up */
3110 	    }
3111 	if (!leftfirst)
3112 	{
3113 	    /* Find the rightmost frame of this row */
3114 	    while (frp->fr_next != NULL)
3115 		frp = frp->fr_next;
3116 	    if (wfw)
3117 		/* Advance back for frames with one window with 'wfw' set. */
3118 		while (frame_fixed_width(frp))
3119 		    frp = frp->fr_prev;
3120 	}
3121 
3122 	extra_cols = width - topfrp->fr_width;
3123 	if (extra_cols < 0)
3124 	{
3125 	    /* reduce frame width, rightmost frame first */
3126 	    while (frp != NULL)
3127 	    {
3128 		w = frame_minwidth(frp, NULL);
3129 		if (frp->fr_width + extra_cols < w)
3130 		{
3131 		    extra_cols += frp->fr_width - w;
3132 		    frame_new_width(frp, w, leftfirst, wfw);
3133 		}
3134 		else
3135 		{
3136 		    frame_new_width(frp, frp->fr_width + extra_cols,
3137 							      leftfirst, wfw);
3138 		    break;
3139 		}
3140 		if (leftfirst)
3141 		{
3142 		    do
3143 			frp = frp->fr_next;
3144 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3145 		}
3146 		else
3147 		{
3148 		    do
3149 			frp = frp->fr_prev;
3150 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3151 		}
3152 		/* Increase "width" if we could not reduce enough frames. */
3153 		if (frp == NULL)
3154 		    width -= extra_cols;
3155 	    }
3156 	}
3157 	else if (extra_cols > 0)
3158 	{
3159 	    /* increase width of rightmost frame */
3160 	    frame_new_width(frp, frp->fr_width + extra_cols, leftfirst, wfw);
3161 	}
3162     }
3163     topfrp->fr_width = width;
3164 }
3165 
3166 /*
3167  * Add the vertical separator to windows at the right side of "frp".
3168  * Note: Does not check if there is room!
3169  */
3170     static void
3171 frame_add_vsep(frame_T *frp)
3172 {
3173     win_T	*wp;
3174 
3175     if (frp->fr_layout == FR_LEAF)
3176     {
3177 	wp = frp->fr_win;
3178 	if (wp->w_vsep_width == 0)
3179 	{
3180 	    if (wp->w_width > 0)	/* don't make it negative */
3181 		--wp->w_width;
3182 	    wp->w_vsep_width = 1;
3183 	}
3184     }
3185     else if (frp->fr_layout == FR_COL)
3186     {
3187 	/* Handle all the frames in the column. */
3188 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3189 	    frame_add_vsep(frp);
3190     }
3191     else /* frp->fr_layout == FR_ROW */
3192     {
3193 	/* Only need to handle the last frame in the row. */
3194 	frp = frp->fr_child;
3195 	while (frp->fr_next != NULL)
3196 	    frp = frp->fr_next;
3197 	frame_add_vsep(frp);
3198     }
3199 }
3200 
3201 /*
3202  * Set frame width from the window it contains.
3203  */
3204     static void
3205 frame_fix_width(win_T *wp)
3206 {
3207     wp->w_frame->fr_width = wp->w_width + wp->w_vsep_width;
3208 }
3209 
3210 /*
3211  * Set frame height from the window it contains.
3212  */
3213     static void
3214 frame_fix_height(win_T *wp)
3215 {
3216     wp->w_frame->fr_height = wp->w_height + wp->w_status_height;
3217 }
3218 
3219 /*
3220  * Compute the minimal height for frame "topfrp".
3221  * Uses the 'winminheight' option.
3222  * When "next_curwin" isn't NULL, use p_wh for this window.
3223  * When "next_curwin" is NOWIN, don't use at least one line for the current
3224  * window.
3225  */
3226     static int
3227 frame_minheight(frame_T *topfrp, win_T *next_curwin)
3228 {
3229     frame_T	*frp;
3230     int		m;
3231     int		n;
3232 
3233     if (topfrp->fr_win != NULL)
3234     {
3235 	if (topfrp->fr_win == next_curwin)
3236 	    m = p_wh + topfrp->fr_win->w_status_height;
3237 	else
3238 	{
3239 	    /* window: minimal height of the window plus status line */
3240 	    m = p_wmh + topfrp->fr_win->w_status_height;
3241 	    /* Current window is minimal one line high */
3242 	    if (p_wmh == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3243 		++m;
3244 	}
3245     }
3246     else if (topfrp->fr_layout == FR_ROW)
3247     {
3248 	/* get the minimal height from each frame in this row */
3249 	m = 0;
3250 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3251 	{
3252 	    n = frame_minheight(frp, next_curwin);
3253 	    if (n > m)
3254 		m = n;
3255 	}
3256     }
3257     else
3258     {
3259 	/* Add up the minimal heights for all frames in this column. */
3260 	m = 0;
3261 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3262 	    m += frame_minheight(frp, next_curwin);
3263     }
3264 
3265     return m;
3266 }
3267 
3268 /*
3269  * Compute the minimal width for frame "topfrp".
3270  * When "next_curwin" isn't NULL, use p_wiw for this window.
3271  * When "next_curwin" is NOWIN, don't use at least one column for the current
3272  * window.
3273  */
3274     static int
3275 frame_minwidth(
3276     frame_T	*topfrp,
3277     win_T	*next_curwin)	/* use p_wh and p_wiw for next_curwin */
3278 {
3279     frame_T	*frp;
3280     int		m, n;
3281 
3282     if (topfrp->fr_win != NULL)
3283     {
3284 	if (topfrp->fr_win == next_curwin)
3285 	    m = p_wiw + topfrp->fr_win->w_vsep_width;
3286 	else
3287 	{
3288 	    /* window: minimal width of the window plus separator column */
3289 	    m = p_wmw + topfrp->fr_win->w_vsep_width;
3290 	    /* Current window is minimal one column wide */
3291 	    if (p_wmw == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3292 		++m;
3293 	}
3294     }
3295     else if (topfrp->fr_layout == FR_COL)
3296     {
3297 	/* get the minimal width from each frame in this column */
3298 	m = 0;
3299 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3300 	{
3301 	    n = frame_minwidth(frp, next_curwin);
3302 	    if (n > m)
3303 		m = n;
3304 	}
3305     }
3306     else
3307     {
3308 	/* Add up the minimal widths for all frames in this row. */
3309 	m = 0;
3310 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3311 	    m += frame_minwidth(frp, next_curwin);
3312     }
3313 
3314     return m;
3315 }
3316 
3317 
3318 /*
3319  * Try to close all windows except current one.
3320  * Buffers in the other windows become hidden if 'hidden' is set, or '!' is
3321  * used and the buffer was modified.
3322  *
3323  * Used by ":bdel" and ":only".
3324  */
3325     void
3326 close_others(
3327     int		message,
3328     int		forceit)	    /* always hide all other windows */
3329 {
3330     win_T	*wp;
3331     win_T	*nextwp;
3332     int		r;
3333 
3334     if (one_window())
3335     {
3336 	if (message
3337 #ifdef FEAT_AUTOCMD
3338 		    && !autocmd_busy
3339 #endif
3340 				    )
3341 	    MSG(_(m_onlyone));
3342 	return;
3343     }
3344 
3345     /* Be very careful here: autocommands may change the window layout. */
3346     for (wp = firstwin; win_valid(wp); wp = nextwp)
3347     {
3348 	nextwp = wp->w_next;
3349 	if (wp != curwin)		/* don't close current window */
3350 	{
3351 
3352 	    /* Check if it's allowed to abandon this window */
3353 	    r = can_abandon(wp->w_buffer, forceit);
3354 #ifdef FEAT_AUTOCMD
3355 	    if (!win_valid(wp))		/* autocommands messed wp up */
3356 	    {
3357 		nextwp = firstwin;
3358 		continue;
3359 	    }
3360 #endif
3361 	    if (!r)
3362 	    {
3363 #if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
3364 		if (message && (p_confirm || cmdmod.confirm) && p_write)
3365 		{
3366 		    dialog_changed(wp->w_buffer, FALSE);
3367 # ifdef FEAT_AUTOCMD
3368 		    if (!win_valid(wp))		/* autocommands messed wp up */
3369 		    {
3370 			nextwp = firstwin;
3371 			continue;
3372 		    }
3373 # endif
3374 		}
3375 		if (bufIsChanged(wp->w_buffer))
3376 #endif
3377 		    continue;
3378 	    }
3379 	    win_close(wp, !P_HID(wp->w_buffer) && !bufIsChanged(wp->w_buffer));
3380 	}
3381     }
3382 
3383     if (message && !ONE_WINDOW)
3384 	EMSG(_("E445: Other window contains changes"));
3385 }
3386 
3387 #endif /* FEAT_WINDOWS */
3388 
3389 /*
3390  * Init the current window "curwin".
3391  * Called when a new file is being edited.
3392  */
3393     void
3394 curwin_init(void)
3395 {
3396     win_init_empty(curwin);
3397 }
3398 
3399     void
3400 win_init_empty(win_T *wp)
3401 {
3402     redraw_win_later(wp, NOT_VALID);
3403     wp->w_lines_valid = 0;
3404     wp->w_cursor.lnum = 1;
3405     wp->w_curswant = wp->w_cursor.col = 0;
3406 #ifdef FEAT_VIRTUALEDIT
3407     wp->w_cursor.coladd = 0;
3408 #endif
3409     wp->w_pcmark.lnum = 1;	/* pcmark not cleared but set to line 1 */
3410     wp->w_pcmark.col = 0;
3411     wp->w_prev_pcmark.lnum = 0;
3412     wp->w_prev_pcmark.col = 0;
3413     wp->w_topline = 1;
3414 #ifdef FEAT_DIFF
3415     wp->w_topfill = 0;
3416 #endif
3417     wp->w_botline = 2;
3418 #ifdef FEAT_FKMAP
3419     if (wp->w_p_rl)
3420 	wp->w_farsi = W_CONV + W_R_L;
3421     else
3422 	wp->w_farsi = W_CONV;
3423 #endif
3424 #ifdef FEAT_SYN_HL
3425     wp->w_s = &wp->w_buffer->b_s;
3426 #endif
3427 }
3428 
3429 /*
3430  * Allocate the first window and put an empty buffer in it.
3431  * Called from main().
3432  * Return FAIL when something goes wrong (out of memory).
3433  */
3434     int
3435 win_alloc_first(void)
3436 {
3437     if (win_alloc_firstwin(NULL) == FAIL)
3438 	return FAIL;
3439 
3440 #ifdef FEAT_WINDOWS
3441     first_tabpage = alloc_tabpage();
3442     if (first_tabpage == NULL)
3443 	return FAIL;
3444     first_tabpage->tp_topframe = topframe;
3445     curtab = first_tabpage;
3446 #endif
3447 
3448     return OK;
3449 }
3450 
3451 #if defined(FEAT_AUTOCMD) || defined(PROTO)
3452 /*
3453  * Init "aucmd_win".  This can only be done after the first
3454  * window is fully initialized, thus it can't be in win_alloc_first().
3455  */
3456     void
3457 win_alloc_aucmd_win(void)
3458 {
3459     aucmd_win = win_alloc(NULL, TRUE);
3460     if (aucmd_win != NULL)
3461     {
3462 	win_init_some(aucmd_win, curwin);
3463 	RESET_BINDING(aucmd_win);
3464 	new_frame(aucmd_win);
3465     }
3466 }
3467 #endif
3468 
3469 /*
3470  * Allocate the first window or the first window in a new tab page.
3471  * When "oldwin" is NULL create an empty buffer for it.
3472  * When "oldwin" is not NULL copy info from it to the new window (only with
3473  * FEAT_WINDOWS).
3474  * Return FAIL when something goes wrong (out of memory).
3475  */
3476     static int
3477 win_alloc_firstwin(win_T *oldwin)
3478 {
3479     curwin = win_alloc(NULL, FALSE);
3480     if (oldwin == NULL)
3481     {
3482 	/* Very first window, need to create an empty buffer for it and
3483 	 * initialize from scratch. */
3484 	curbuf = buflist_new(NULL, NULL, 1L, BLN_LISTED);
3485 	if (curwin == NULL || curbuf == NULL)
3486 	    return FAIL;
3487 	curwin->w_buffer = curbuf;
3488 #ifdef FEAT_SYN_HL
3489 	curwin->w_s = &(curbuf->b_s);
3490 #endif
3491 	curbuf->b_nwindows = 1;	/* there is one window */
3492 #ifdef FEAT_WINDOWS
3493 	curwin->w_alist = &global_alist;
3494 #endif
3495 	curwin_init();		/* init current window */
3496     }
3497 #ifdef FEAT_WINDOWS
3498     else
3499     {
3500 	/* First window in new tab page, initialize it from "oldwin". */
3501 	win_init(curwin, oldwin, 0);
3502 
3503 	/* We don't want cursor- and scroll-binding in the first window. */
3504 	RESET_BINDING(curwin);
3505     }
3506 #endif
3507 
3508     new_frame(curwin);
3509     if (curwin->w_frame == NULL)
3510 	return FAIL;
3511     topframe = curwin->w_frame;
3512 #ifdef FEAT_WINDOWS
3513     topframe->fr_width = Columns;
3514 #endif
3515     topframe->fr_height = Rows - p_ch;
3516     topframe->fr_win = curwin;
3517 
3518     return OK;
3519 }
3520 
3521 /*
3522  * Create a frame for window "wp".
3523  */
3524     static void
3525 new_frame(win_T *wp)
3526 {
3527     frame_T *frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
3528 
3529     wp->w_frame = frp;
3530     if (frp != NULL)
3531     {
3532 	frp->fr_layout = FR_LEAF;
3533 	frp->fr_win = wp;
3534     }
3535 }
3536 
3537 /*
3538  * Initialize the window and frame size to the maximum.
3539  */
3540     void
3541 win_init_size(void)
3542 {
3543     firstwin->w_height = ROWS_AVAIL;
3544     topframe->fr_height = ROWS_AVAIL;
3545 #ifdef FEAT_WINDOWS
3546     firstwin->w_width = Columns;
3547     topframe->fr_width = Columns;
3548 #endif
3549 }
3550 
3551 #if defined(FEAT_WINDOWS) || defined(PROTO)
3552 
3553 /*
3554  * Allocate a new tabpage_T and init the values.
3555  * Returns NULL when out of memory.
3556  */
3557     static tabpage_T *
3558 alloc_tabpage(void)
3559 {
3560     tabpage_T	*tp;
3561 # ifdef FEAT_GUI
3562     int		i;
3563 # endif
3564 
3565 
3566     tp = (tabpage_T *)alloc_clear((unsigned)sizeof(tabpage_T));
3567     if (tp == NULL)
3568 	return NULL;
3569 
3570 # ifdef FEAT_EVAL
3571     /* init t: variables */
3572     tp->tp_vars = dict_alloc();
3573     if (tp->tp_vars == NULL)
3574     {
3575 	vim_free(tp);
3576 	return NULL;
3577     }
3578     init_var_dict(tp->tp_vars, &tp->tp_winvar, VAR_SCOPE);
3579 # endif
3580 
3581 # ifdef FEAT_GUI
3582     for (i = 0; i < 3; i++)
3583 	tp->tp_prev_which_scrollbars[i] = -1;
3584 # endif
3585 # ifdef FEAT_DIFF
3586     tp->tp_diff_invalid = TRUE;
3587 # endif
3588     tp->tp_ch_used = p_ch;
3589 
3590     return tp;
3591 }
3592 
3593     void
3594 free_tabpage(tabpage_T *tp)
3595 {
3596     int idx;
3597 
3598 # ifdef FEAT_DIFF
3599     diff_clear(tp);
3600 # endif
3601     for (idx = 0; idx < SNAP_COUNT; ++idx)
3602 	clear_snapshot(tp, idx);
3603 #ifdef FEAT_EVAL
3604     vars_clear(&tp->tp_vars->dv_hashtab);	/* free all t: variables */
3605     hash_init(&tp->tp_vars->dv_hashtab);
3606     unref_var_dict(tp->tp_vars);
3607 #endif
3608 
3609 #ifdef FEAT_PYTHON
3610     python_tabpage_free(tp);
3611 #endif
3612 
3613 #ifdef FEAT_PYTHON3
3614     python3_tabpage_free(tp);
3615 #endif
3616 
3617     vim_free(tp);
3618 }
3619 
3620 /*
3621  * Create a new Tab page with one window.
3622  * It will edit the current buffer, like after ":split".
3623  * When "after" is 0 put it just after the current Tab page.
3624  * Otherwise put it just before tab page "after".
3625  * Return FAIL or OK.
3626  */
3627     int
3628 win_new_tabpage(int after)
3629 {
3630     tabpage_T	*tp = curtab;
3631     tabpage_T	*newtp;
3632     int		n;
3633 
3634     newtp = alloc_tabpage();
3635     if (newtp == NULL)
3636 	return FAIL;
3637 
3638     /* Remember the current windows in this Tab page. */
3639     if (leave_tabpage(curbuf, TRUE) == FAIL)
3640     {
3641 	vim_free(newtp);
3642 	return FAIL;
3643     }
3644     curtab = newtp;
3645 
3646     /* Create a new empty window. */
3647     if (win_alloc_firstwin(tp->tp_curwin) == OK)
3648     {
3649 	/* Make the new Tab page the new topframe. */
3650 	if (after == 1)
3651 	{
3652 	    /* New tab page becomes the first one. */
3653 	    newtp->tp_next = first_tabpage;
3654 	    first_tabpage = newtp;
3655 	}
3656 	else
3657 	{
3658 	    if (after > 0)
3659 	    {
3660 		/* Put new tab page before tab page "after". */
3661 		n = 2;
3662 		for (tp = first_tabpage; tp->tp_next != NULL
3663 					       && n < after; tp = tp->tp_next)
3664 		    ++n;
3665 	    }
3666 	    newtp->tp_next = tp->tp_next;
3667 	    tp->tp_next = newtp;
3668 	}
3669 	win_init_size();
3670 	firstwin->w_winrow = tabline_height();
3671 	win_comp_scroll(curwin);
3672 
3673 	newtp->tp_topframe = topframe;
3674 	last_status(FALSE);
3675 
3676 #if defined(FEAT_GUI)
3677 	/* When 'guioptions' includes 'L' or 'R' may have to remove or add
3678 	 * scrollbars.  Have to update them anyway. */
3679 	gui_may_update_scrollbars();
3680 #endif
3681 
3682 	redraw_all_later(CLEAR);
3683 #ifdef FEAT_AUTOCMD
3684 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
3685 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
3686 	apply_autocmds(EVENT_TABNEW, NULL, NULL, FALSE, curbuf);
3687 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3688 #endif
3689 	return OK;
3690     }
3691 
3692     /* Failed, get back the previous Tab page */
3693     enter_tabpage(curtab, curbuf, TRUE, TRUE);
3694     return FAIL;
3695 }
3696 
3697 /*
3698  * Open a new tab page if ":tab cmd" was used.  It will edit the same buffer,
3699  * like with ":split".
3700  * Returns OK if a new tab page was created, FAIL otherwise.
3701  */
3702     int
3703 may_open_tabpage(void)
3704 {
3705     int		n = (cmdmod.tab == 0) ? postponed_split_tab : cmdmod.tab;
3706 
3707     if (n != 0)
3708     {
3709 	cmdmod.tab = 0;	    /* reset it to avoid doing it twice */
3710 	postponed_split_tab = 0;
3711 	return win_new_tabpage(n);
3712     }
3713     return FAIL;
3714 }
3715 
3716 /*
3717  * Create up to "maxcount" tabpages with empty windows.
3718  * Returns the number of resulting tab pages.
3719  */
3720     int
3721 make_tabpages(int maxcount)
3722 {
3723     int		count = maxcount;
3724     int		todo;
3725 
3726     /* Limit to 'tabpagemax' tabs. */
3727     if (count > p_tpm)
3728 	count = p_tpm;
3729 
3730 #ifdef FEAT_AUTOCMD
3731     /*
3732      * Don't execute autocommands while creating the tab pages.  Must do that
3733      * when putting the buffers in the windows.
3734      */
3735     block_autocmds();
3736 #endif
3737 
3738     for (todo = count - 1; todo > 0; --todo)
3739 	if (win_new_tabpage(0) == FAIL)
3740 	    break;
3741 
3742 #ifdef FEAT_AUTOCMD
3743     unblock_autocmds();
3744 #endif
3745 
3746     /* return actual number of tab pages */
3747     return (count - todo);
3748 }
3749 
3750 /*
3751  * Return TRUE when "tpc" points to a valid tab page.
3752  */
3753     int
3754 valid_tabpage(tabpage_T *tpc)
3755 {
3756     tabpage_T	*tp;
3757 
3758     FOR_ALL_TABPAGES(tp)
3759 	if (tp == tpc)
3760 	    return TRUE;
3761     return FALSE;
3762 }
3763 
3764 /*
3765  * Return TRUE when "tpc" points to a valid tab page and at least one window is
3766  * valid.
3767  */
3768     int
3769 valid_tabpage_win(tabpage_T *tpc)
3770 {
3771     tabpage_T	*tp;
3772     win_T	*wp;
3773 
3774     FOR_ALL_TABPAGES(tp)
3775     {
3776 	if (tp == tpc)
3777 	{
3778 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
3779 	    {
3780 		if (win_valid_any_tab(wp))
3781 		    return TRUE;
3782 	    }
3783 	    return FALSE;
3784 	}
3785     }
3786     /* shouldn't happen */
3787     return FALSE;
3788 }
3789 
3790 /*
3791  * Close tabpage "tab", assuming it has no windows in it.
3792  * There must be another tabpage or this will crash.
3793  */
3794     void
3795 close_tabpage(tabpage_T *tab)
3796 {
3797     tabpage_T	*ptp;
3798 
3799     if (tab == first_tabpage)
3800     {
3801 	first_tabpage = tab->tp_next;
3802 	ptp = first_tabpage;
3803     }
3804     else
3805     {
3806 	for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tab;
3807 							    ptp = ptp->tp_next)
3808 	    ;
3809 	assert(ptp != NULL);
3810 	ptp->tp_next = tab->tp_next;
3811     }
3812 
3813     goto_tabpage_tp(ptp, FALSE, FALSE);
3814     free_tabpage(tab);
3815 }
3816 
3817 /*
3818  * Find tab page "n" (first one is 1).  Returns NULL when not found.
3819  */
3820     tabpage_T *
3821 find_tabpage(int n)
3822 {
3823     tabpage_T	*tp;
3824     int		i = 1;
3825 
3826     for (tp = first_tabpage; tp != NULL && i != n; tp = tp->tp_next)
3827 	++i;
3828     return tp;
3829 }
3830 
3831 /*
3832  * Get index of tab page "tp".  First one has index 1.
3833  * When not found returns number of tab pages plus one.
3834  */
3835     int
3836 tabpage_index(tabpage_T *ftp)
3837 {
3838     int		i = 1;
3839     tabpage_T	*tp;
3840 
3841     for (tp = first_tabpage; tp != NULL && tp != ftp; tp = tp->tp_next)
3842 	++i;
3843     return i;
3844 }
3845 
3846 /*
3847  * Prepare for leaving the current tab page.
3848  * When autocommands change "curtab" we don't leave the tab page and return
3849  * FAIL.
3850  * Careful: When OK is returned need to get a new tab page very very soon!
3851  */
3852     static int
3853 leave_tabpage(
3854     buf_T	*new_curbuf UNUSED,    /* what is going to be the new curbuf,
3855 				       NULL if unknown */
3856     int		trigger_leave_autocmds UNUSED)
3857 {
3858     tabpage_T	*tp = curtab;
3859 
3860     reset_VIsual_and_resel();	/* stop Visual mode */
3861 #ifdef FEAT_AUTOCMD
3862     if (trigger_leave_autocmds)
3863     {
3864 	if (new_curbuf != curbuf)
3865 	{
3866 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
3867 	    if (curtab != tp)
3868 		return FAIL;
3869 	}
3870 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
3871 	if (curtab != tp)
3872 	    return FAIL;
3873 	apply_autocmds(EVENT_TABLEAVE, NULL, NULL, FALSE, curbuf);
3874 	if (curtab != tp)
3875 	    return FAIL;
3876     }
3877 #endif
3878 #if defined(FEAT_GUI)
3879     /* Remove the scrollbars.  They may be added back later. */
3880     if (gui.in_use)
3881 	gui_remove_scrollbars();
3882 #endif
3883     tp->tp_curwin = curwin;
3884     tp->tp_prevwin = prevwin;
3885     tp->tp_firstwin = firstwin;
3886     tp->tp_lastwin = lastwin;
3887     tp->tp_old_Rows = Rows;
3888     tp->tp_old_Columns = Columns;
3889     firstwin = NULL;
3890     lastwin = NULL;
3891     return OK;
3892 }
3893 
3894 /*
3895  * Start using tab page "tp".
3896  * Only to be used after leave_tabpage() or freeing the current tab page.
3897  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
3898  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
3899  */
3900     static void
3901 enter_tabpage(
3902     tabpage_T	*tp,
3903     buf_T	*old_curbuf UNUSED,
3904     int		trigger_enter_autocmds,
3905     int		trigger_leave_autocmds)
3906 {
3907     int		old_off = tp->tp_firstwin->w_winrow;
3908     win_T	*next_prevwin = tp->tp_prevwin;
3909 
3910     curtab = tp;
3911     firstwin = tp->tp_firstwin;
3912     lastwin = tp->tp_lastwin;
3913     topframe = tp->tp_topframe;
3914 
3915     /* We would like doing the TabEnter event first, but we don't have a
3916      * valid current window yet, which may break some commands.
3917      * This triggers autocommands, thus may make "tp" invalid. */
3918     win_enter_ext(tp->tp_curwin, FALSE, TRUE, FALSE,
3919 			      trigger_enter_autocmds, trigger_leave_autocmds);
3920     prevwin = next_prevwin;
3921 
3922     last_status(FALSE);		/* status line may appear or disappear */
3923     (void)win_comp_pos();	/* recompute w_winrow for all windows */
3924     must_redraw = CLEAR;	/* need to redraw everything */
3925 #ifdef FEAT_DIFF
3926     diff_need_scrollbind = TRUE;
3927 #endif
3928 
3929     /* The tabpage line may have appeared or disappeared, may need to resize
3930      * the frames for that.  When the Vim window was resized need to update
3931      * frame sizes too.  Use the stored value of p_ch, so that it can be
3932      * different for each tab page. */
3933     p_ch = curtab->tp_ch_used;
3934     if (curtab->tp_old_Rows != Rows || (old_off != firstwin->w_winrow
3935 #ifdef FEAT_GUI_TABLINE
3936 			    && !gui_use_tabline()
3937 #endif
3938 		))
3939 	shell_new_rows();
3940     if (curtab->tp_old_Columns != Columns && starting == 0)
3941 	shell_new_columns();	/* update window widths */
3942 
3943 #if defined(FEAT_GUI)
3944     /* When 'guioptions' includes 'L' or 'R' may have to remove or add
3945      * scrollbars.  Have to update them anyway. */
3946     gui_may_update_scrollbars();
3947 #endif
3948 
3949 #ifdef FEAT_AUTOCMD
3950     /* Apply autocommands after updating the display, when 'rows' and
3951      * 'columns' have been set correctly. */
3952     if (trigger_enter_autocmds)
3953     {
3954 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3955 	if (old_curbuf != curbuf)
3956 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
3957     }
3958 #endif
3959 
3960     redraw_all_later(CLEAR);
3961 }
3962 
3963 /*
3964  * Go to tab page "n".  For ":tab N" and "Ngt".
3965  * When "n" is 9999 go to the last tab page.
3966  */
3967     void
3968 goto_tabpage(int n)
3969 {
3970     tabpage_T	*tp;
3971     tabpage_T	*ttp;
3972     int		i;
3973 
3974     if (text_locked())
3975     {
3976 	/* Not allowed when editing the command line. */
3977 	text_locked_msg();
3978 	return;
3979     }
3980 
3981     /* If there is only one it can't work. */
3982     if (first_tabpage->tp_next == NULL)
3983     {
3984 	if (n > 1)
3985 	    beep_flush();
3986 	return;
3987     }
3988 
3989     if (n == 0)
3990     {
3991 	/* No count, go to next tab page, wrap around end. */
3992 	if (curtab->tp_next == NULL)
3993 	    tp = first_tabpage;
3994 	else
3995 	    tp = curtab->tp_next;
3996     }
3997     else if (n < 0)
3998     {
3999 	/* "gT": go to previous tab page, wrap around end.  "N gT" repeats
4000 	 * this N times. */
4001 	ttp = curtab;
4002 	for (i = n; i < 0; ++i)
4003 	{
4004 	    for (tp = first_tabpage; tp->tp_next != ttp && tp->tp_next != NULL;
4005 		    tp = tp->tp_next)
4006 		;
4007 	    ttp = tp;
4008 	}
4009     }
4010     else if (n == 9999)
4011     {
4012 	/* Go to last tab page. */
4013 	for (tp = first_tabpage; tp->tp_next != NULL; tp = tp->tp_next)
4014 	    ;
4015     }
4016     else
4017     {
4018 	/* Go to tab page "n". */
4019 	tp = find_tabpage(n);
4020 	if (tp == NULL)
4021 	{
4022 	    beep_flush();
4023 	    return;
4024 	}
4025     }
4026 
4027     goto_tabpage_tp(tp, TRUE, TRUE);
4028 
4029 #ifdef FEAT_GUI_TABLINE
4030     if (gui_use_tabline())
4031 	gui_mch_set_curtab(tabpage_index(curtab));
4032 #endif
4033 }
4034 
4035 /*
4036  * Go to tabpage "tp".
4037  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4038  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4039  * Note: doesn't update the GUI tab.
4040  */
4041     void
4042 goto_tabpage_tp(
4043     tabpage_T	*tp,
4044     int		trigger_enter_autocmds,
4045     int		trigger_leave_autocmds)
4046 {
4047     /* Don't repeat a message in another tab page. */
4048     set_keep_msg(NULL, 0);
4049 
4050     if (tp != curtab && leave_tabpage(tp->tp_curwin->w_buffer,
4051 					trigger_leave_autocmds) == OK)
4052     {
4053 	if (valid_tabpage(tp))
4054 	    enter_tabpage(tp, curbuf, trigger_enter_autocmds,
4055 		    trigger_leave_autocmds);
4056 	else
4057 	    enter_tabpage(curtab, curbuf, trigger_enter_autocmds,
4058 		    trigger_leave_autocmds);
4059     }
4060 }
4061 
4062 /*
4063  * Enter window "wp" in tab page "tp".
4064  * Also updates the GUI tab.
4065  */
4066     void
4067 goto_tabpage_win(tabpage_T *tp, win_T *wp)
4068 {
4069     goto_tabpage_tp(tp, TRUE, TRUE);
4070     if (curtab == tp && win_valid(wp))
4071     {
4072 	win_enter(wp, TRUE);
4073 # ifdef FEAT_GUI_TABLINE
4074 	if (gui_use_tabline())
4075 	    gui_mch_set_curtab(tabpage_index(curtab));
4076 # endif
4077     }
4078 }
4079 
4080 /*
4081  * Move the current tab page to after tab page "nr".
4082  */
4083     void
4084 tabpage_move(int nr)
4085 {
4086     int		n = 1;
4087     tabpage_T	*tp, *tp_dst;
4088 
4089     if (first_tabpage->tp_next == NULL)
4090 	return;
4091 
4092     for (tp = first_tabpage; tp->tp_next != NULL && n < nr; tp = tp->tp_next)
4093 	++n;
4094 
4095     if (tp == curtab || (nr > 0 && tp->tp_next != NULL
4096 						    && tp->tp_next == curtab))
4097 	return;
4098 
4099     tp_dst = tp;
4100 
4101     /* Remove the current tab page from the list of tab pages. */
4102     if (curtab == first_tabpage)
4103 	first_tabpage = curtab->tp_next;
4104     else
4105     {
4106 	FOR_ALL_TABPAGES(tp)
4107 	    if (tp->tp_next == curtab)
4108 		break;
4109 	if (tp == NULL)	/* "cannot happen" */
4110 	    return;
4111 	tp->tp_next = curtab->tp_next;
4112     }
4113 
4114     /* Re-insert it at the specified position. */
4115     if (nr <= 0)
4116     {
4117 	curtab->tp_next = first_tabpage;
4118 	first_tabpage = curtab;
4119     }
4120     else
4121     {
4122 	curtab->tp_next = tp_dst->tp_next;
4123 	tp_dst->tp_next = curtab;
4124     }
4125 
4126     /* Need to redraw the tabline.  Tab page contents doesn't change. */
4127     redraw_tabline = TRUE;
4128 }
4129 
4130 
4131 /*
4132  * Go to another window.
4133  * When jumping to another buffer, stop Visual mode.  Do this before
4134  * changing windows so we can yank the selection into the '*' register.
4135  * When jumping to another window on the same buffer, adjust its cursor
4136  * position to keep the same Visual area.
4137  */
4138     void
4139 win_goto(win_T *wp)
4140 {
4141 #ifdef FEAT_CONCEAL
4142     win_T	*owp = curwin;
4143 #endif
4144 
4145     if (text_locked())
4146     {
4147 	beep_flush();
4148 	text_locked_msg();
4149 	return;
4150     }
4151 #ifdef FEAT_AUTOCMD
4152     if (curbuf_locked())
4153 	return;
4154 #endif
4155 
4156     if (wp->w_buffer != curbuf)
4157 	reset_VIsual_and_resel();
4158     else if (VIsual_active)
4159 	wp->w_cursor = curwin->w_cursor;
4160 
4161 #ifdef FEAT_GUI
4162     need_mouse_correct = TRUE;
4163 #endif
4164     win_enter(wp, TRUE);
4165 
4166 #ifdef FEAT_CONCEAL
4167     /* Conceal cursor line in previous window, unconceal in current window. */
4168     if (win_valid(owp) && owp->w_p_cole > 0 && !msg_scrolled)
4169 	update_single_line(owp, owp->w_cursor.lnum);
4170     if (curwin->w_p_cole > 0 && !msg_scrolled)
4171 	need_cursor_line_redraw = TRUE;
4172 #endif
4173 }
4174 
4175 #if defined(FEAT_PERL) || defined(PROTO)
4176 /*
4177  * Find window number "winnr" (counting top to bottom).
4178  */
4179     win_T *
4180 win_find_nr(int winnr)
4181 {
4182     win_T	*wp;
4183 
4184 # ifdef FEAT_WINDOWS
4185     FOR_ALL_WINDOWS(wp)
4186 	if (--winnr == 0)
4187 	    break;
4188     return wp;
4189 # else
4190     return curwin;
4191 # endif
4192 }
4193 #endif
4194 
4195 #if (defined(FEAT_WINDOWS) && (defined(FEAT_PYTHON) || defined(FEAT_PYTHON3))) \
4196 	|| defined(PROTO)
4197 /*
4198  * Find the tabpage for window "win".
4199  */
4200     tabpage_T *
4201 win_find_tabpage(win_T *win)
4202 {
4203     win_T	*wp;
4204     tabpage_T	*tp;
4205 
4206     FOR_ALL_TAB_WINDOWS(tp, wp)
4207 	    if (wp == win)
4208 		return tp;
4209     return NULL;
4210 }
4211 #endif
4212 
4213 /*
4214  * Move to window above or below "count" times.
4215  */
4216     static void
4217 win_goto_ver(
4218     int		up,		/* TRUE to go to win above */
4219     long	count)
4220 {
4221     frame_T	*fr;
4222     frame_T	*nfr;
4223     frame_T	*foundfr;
4224 
4225     foundfr = curwin->w_frame;
4226     while (count--)
4227     {
4228 	/*
4229 	 * First go upwards in the tree of frames until we find a upwards or
4230 	 * downwards neighbor.
4231 	 */
4232 	fr = foundfr;
4233 	for (;;)
4234 	{
4235 	    if (fr == topframe)
4236 		goto end;
4237 	    if (up)
4238 		nfr = fr->fr_prev;
4239 	    else
4240 		nfr = fr->fr_next;
4241 	    if (fr->fr_parent->fr_layout == FR_COL && nfr != NULL)
4242 		break;
4243 	    fr = fr->fr_parent;
4244 	}
4245 
4246 	/*
4247 	 * Now go downwards to find the bottom or top frame in it.
4248 	 */
4249 	for (;;)
4250 	{
4251 	    if (nfr->fr_layout == FR_LEAF)
4252 	    {
4253 		foundfr = nfr;
4254 		break;
4255 	    }
4256 	    fr = nfr->fr_child;
4257 	    if (nfr->fr_layout == FR_ROW)
4258 	    {
4259 		/* Find the frame at the cursor row. */
4260 		while (fr->fr_next != NULL
4261 			&& frame2win(fr)->w_wincol + fr->fr_width
4262 					 <= curwin->w_wincol + curwin->w_wcol)
4263 		    fr = fr->fr_next;
4264 	    }
4265 	    if (nfr->fr_layout == FR_COL && up)
4266 		while (fr->fr_next != NULL)
4267 		    fr = fr->fr_next;
4268 	    nfr = fr;
4269 	}
4270     }
4271 end:
4272     if (foundfr != NULL)
4273 	win_goto(foundfr->fr_win);
4274 }
4275 
4276 /*
4277  * Move to left or right window.
4278  */
4279     static void
4280 win_goto_hor(
4281     int		left,		/* TRUE to go to left win */
4282     long	count)
4283 {
4284     frame_T	*fr;
4285     frame_T	*nfr;
4286     frame_T	*foundfr;
4287 
4288     foundfr = curwin->w_frame;
4289     while (count--)
4290     {
4291 	/*
4292 	 * First go upwards in the tree of frames until we find a left or
4293 	 * right neighbor.
4294 	 */
4295 	fr = foundfr;
4296 	for (;;)
4297 	{
4298 	    if (fr == topframe)
4299 		goto end;
4300 	    if (left)
4301 		nfr = fr->fr_prev;
4302 	    else
4303 		nfr = fr->fr_next;
4304 	    if (fr->fr_parent->fr_layout == FR_ROW && nfr != NULL)
4305 		break;
4306 	    fr = fr->fr_parent;
4307 	}
4308 
4309 	/*
4310 	 * Now go downwards to find the leftmost or rightmost frame in it.
4311 	 */
4312 	for (;;)
4313 	{
4314 	    if (nfr->fr_layout == FR_LEAF)
4315 	    {
4316 		foundfr = nfr;
4317 		break;
4318 	    }
4319 	    fr = nfr->fr_child;
4320 	    if (nfr->fr_layout == FR_COL)
4321 	    {
4322 		/* Find the frame at the cursor row. */
4323 		while (fr->fr_next != NULL
4324 			&& frame2win(fr)->w_winrow + fr->fr_height
4325 					 <= curwin->w_winrow + curwin->w_wrow)
4326 		    fr = fr->fr_next;
4327 	    }
4328 	    if (nfr->fr_layout == FR_ROW && left)
4329 		while (fr->fr_next != NULL)
4330 		    fr = fr->fr_next;
4331 	    nfr = fr;
4332 	}
4333     }
4334 end:
4335     if (foundfr != NULL)
4336 	win_goto(foundfr->fr_win);
4337 }
4338 
4339 /*
4340  * Make window "wp" the current window.
4341  */
4342     void
4343 win_enter(win_T *wp, int undo_sync)
4344 {
4345     win_enter_ext(wp, undo_sync, FALSE, FALSE, TRUE, TRUE);
4346 }
4347 
4348 /*
4349  * Make window wp the current window.
4350  * Can be called with "curwin_invalid" TRUE, which means that curwin has just
4351  * been closed and isn't valid.
4352  */
4353     static void
4354 win_enter_ext(
4355     win_T	*wp,
4356     int		undo_sync,
4357     int		curwin_invalid,
4358     int		trigger_new_autocmds UNUSED,
4359     int		trigger_enter_autocmds UNUSED,
4360     int		trigger_leave_autocmds UNUSED)
4361 {
4362 #ifdef FEAT_AUTOCMD
4363     int		other_buffer = FALSE;
4364 #endif
4365 
4366     if (wp == curwin && !curwin_invalid)	/* nothing to do */
4367 	return;
4368 
4369 #ifdef FEAT_AUTOCMD
4370     if (!curwin_invalid && trigger_leave_autocmds)
4371     {
4372 	/*
4373 	 * Be careful: If autocommands delete the window, return now.
4374 	 */
4375 	if (wp->w_buffer != curbuf)
4376 	{
4377 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4378 	    other_buffer = TRUE;
4379 	    if (!win_valid(wp))
4380 		return;
4381 	}
4382 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4383 	if (!win_valid(wp))
4384 	    return;
4385 # ifdef FEAT_EVAL
4386 	/* autocmds may abort script processing */
4387 	if (aborting())
4388 	    return;
4389 # endif
4390     }
4391 #endif
4392 
4393     /* sync undo before leaving the current buffer */
4394     if (undo_sync && curbuf != wp->w_buffer)
4395 	u_sync(FALSE);
4396 
4397     /* Might need to scroll the old window before switching, e.g., when the
4398      * cursor was moved. */
4399     update_topline();
4400 
4401     /* may have to copy the buffer options when 'cpo' contains 'S' */
4402     if (wp->w_buffer != curbuf)
4403 	buf_copy_options(wp->w_buffer, BCO_ENTER | BCO_NOHELP);
4404     if (!curwin_invalid)
4405     {
4406 	prevwin = curwin;	/* remember for CTRL-W p */
4407 	curwin->w_redr_status = TRUE;
4408     }
4409     curwin = wp;
4410     curbuf = wp->w_buffer;
4411     check_cursor();
4412 #ifdef FEAT_VIRTUALEDIT
4413     if (!virtual_active())
4414 	curwin->w_cursor.coladd = 0;
4415 #endif
4416     changed_line_abv_curs();	/* assume cursor position needs updating */
4417 
4418     if (curwin->w_localdir != NULL)
4419     {
4420 	/* Window has a local directory: Save current directory as global
4421 	 * directory (unless that was done already) and change to the local
4422 	 * directory. */
4423 	if (globaldir == NULL)
4424 	{
4425 	    char_u	cwd[MAXPATHL];
4426 
4427 	    if (mch_dirname(cwd, MAXPATHL) == OK)
4428 		globaldir = vim_strsave(cwd);
4429 	}
4430 	if (mch_chdir((char *)curwin->w_localdir) == 0)
4431 	    shorten_fnames(TRUE);
4432     }
4433     else if (globaldir != NULL)
4434     {
4435 	/* Window doesn't have a local directory and we are not in the global
4436 	 * directory: Change to the global directory. */
4437 	ignored = mch_chdir((char *)globaldir);
4438 	vim_free(globaldir);
4439 	globaldir = NULL;
4440 	shorten_fnames(TRUE);
4441     }
4442 
4443 #ifdef FEAT_AUTOCMD
4444     if (trigger_new_autocmds)
4445 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
4446     if (trigger_enter_autocmds)
4447     {
4448 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
4449 	if (other_buffer)
4450 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4451     }
4452 #endif
4453 
4454 #ifdef FEAT_TITLE
4455     maketitle();
4456 #endif
4457     curwin->w_redr_status = TRUE;
4458     redraw_tabline = TRUE;
4459     if (restart_edit)
4460 	redraw_later(VALID);	/* causes status line redraw */
4461 
4462     /* set window height to desired minimal value */
4463     if (curwin->w_height < p_wh && !curwin->w_p_wfh)
4464 	win_setheight((int)p_wh);
4465     else if (curwin->w_height == 0)
4466 	win_setheight(1);
4467 
4468     /* set window width to desired minimal value */
4469     if (curwin->w_width < p_wiw && !curwin->w_p_wfw)
4470 	win_setwidth((int)p_wiw);
4471 
4472 #ifdef FEAT_MOUSE
4473     setmouse();			/* in case jumped to/from help buffer */
4474 #endif
4475 
4476     /* Change directories when the 'acd' option is set. */
4477     DO_AUTOCHDIR
4478 }
4479 
4480 #endif /* FEAT_WINDOWS */
4481 
4482 #if defined(FEAT_WINDOWS) || defined(FEAT_SIGNS) || defined(PROTO)
4483 /*
4484  * Jump to the first open window that contains buffer "buf", if one exists.
4485  * Returns a pointer to the window found, otherwise NULL.
4486  */
4487     win_T *
4488 buf_jump_open_win(buf_T *buf)
4489 {
4490     win_T	*wp = NULL;
4491 
4492     if (curwin->w_buffer == buf)
4493 	wp = curwin;
4494 # ifdef FEAT_WINDOWS
4495     else
4496 	FOR_ALL_WINDOWS(wp)
4497 	    if (wp->w_buffer == buf)
4498 		break;
4499     if (wp != NULL)
4500 	win_enter(wp, FALSE);
4501 # endif
4502     return wp;
4503 }
4504 
4505 /*
4506  * Jump to the first open window in any tab page that contains buffer "buf",
4507  * if one exists.
4508  * Returns a pointer to the window found, otherwise NULL.
4509  */
4510     win_T *
4511 buf_jump_open_tab(buf_T *buf)
4512 {
4513     win_T	*wp = buf_jump_open_win(buf);
4514 # ifdef FEAT_WINDOWS
4515     tabpage_T	*tp;
4516 
4517     if (wp != NULL)
4518 	return wp;
4519 
4520     FOR_ALL_TABPAGES(tp)
4521 	if (tp != curtab)
4522 	{
4523 	    for (wp = tp->tp_firstwin; wp != NULL; wp = wp->w_next)
4524 		if (wp->w_buffer == buf)
4525 		    break;
4526 	    if (wp != NULL)
4527 	    {
4528 		goto_tabpage_win(tp, wp);
4529 		if (curwin != wp)
4530 		    wp = NULL;	/* something went wrong */
4531 		break;
4532 	    }
4533 	}
4534 # endif
4535     return wp;
4536 }
4537 #endif
4538 
4539 static int last_win_id = LOWEST_WIN_ID - 1;
4540 
4541 /*
4542  * Allocate a window structure and link it in the window list when "hidden" is
4543  * FALSE.
4544  */
4545     static win_T *
4546 win_alloc(win_T *after UNUSED, int hidden UNUSED)
4547 {
4548     win_T	*new_wp;
4549 
4550     /*
4551      * allocate window structure and linesizes arrays
4552      */
4553     new_wp = (win_T *)alloc_clear((unsigned)sizeof(win_T));
4554     if (new_wp == NULL)
4555 	return NULL;
4556 
4557     if (win_alloc_lines(new_wp) == FAIL)
4558     {
4559 	vim_free(new_wp);
4560 	return NULL;
4561     }
4562 
4563     new_wp->w_id = ++last_win_id;
4564 
4565 #ifdef FEAT_EVAL
4566     /* init w: variables */
4567     new_wp->w_vars = dict_alloc();
4568     if (new_wp->w_vars == NULL)
4569     {
4570 	win_free_lsize(new_wp);
4571 	vim_free(new_wp);
4572 	return NULL;
4573     }
4574     init_var_dict(new_wp->w_vars, &new_wp->w_winvar, VAR_SCOPE);
4575 #endif
4576 
4577 #ifdef FEAT_AUTOCMD
4578     /* Don't execute autocommands while the window is not properly
4579      * initialized yet.  gui_create_scrollbar() may trigger a FocusGained
4580      * event. */
4581     block_autocmds();
4582 #endif
4583     /*
4584      * link the window in the window list
4585      */
4586 #ifdef FEAT_WINDOWS
4587     if (!hidden)
4588 	win_append(after, new_wp);
4589     new_wp->w_wincol = 0;
4590     new_wp->w_width = Columns;
4591 #endif
4592 
4593     /* position the display and the cursor at the top of the file. */
4594     new_wp->w_topline = 1;
4595 #ifdef FEAT_DIFF
4596     new_wp->w_topfill = 0;
4597 #endif
4598     new_wp->w_botline = 2;
4599     new_wp->w_cursor.lnum = 1;
4600 #ifdef FEAT_SCROLLBIND
4601     new_wp->w_scbind_pos = 1;
4602 #endif
4603 
4604     /* We won't calculate w_fraction until resizing the window */
4605     new_wp->w_fraction = 0;
4606     new_wp->w_prev_fraction_row = -1;
4607 
4608 #ifdef FEAT_GUI
4609     if (gui.in_use)
4610     {
4611 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_LEFT],
4612 		SBAR_LEFT, new_wp);
4613 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_RIGHT],
4614 		SBAR_RIGHT, new_wp);
4615     }
4616 #endif
4617 #ifdef FEAT_FOLDING
4618     foldInitWin(new_wp);
4619 #endif
4620 #ifdef FEAT_AUTOCMD
4621     unblock_autocmds();
4622 #endif
4623 #ifdef FEAT_SEARCH_EXTRA
4624     new_wp->w_match_head = NULL;
4625     new_wp->w_next_match_id = 4;
4626 #endif
4627     return new_wp;
4628 }
4629 
4630 #if defined(FEAT_WINDOWS) || defined(PROTO)
4631 
4632 /*
4633  * Remove window 'wp' from the window list and free the structure.
4634  */
4635     static void
4636 win_free(
4637     win_T	*wp,
4638     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
4639 {
4640     int		i;
4641     buf_T	*buf;
4642     wininfo_T	*wip;
4643 
4644 #ifdef FEAT_FOLDING
4645     clearFolding(wp);
4646 #endif
4647 
4648     /* reduce the reference count to the argument list. */
4649     alist_unlink(wp->w_alist);
4650 
4651 #ifdef FEAT_AUTOCMD
4652     /* Don't execute autocommands while the window is halfway being deleted.
4653      * gui_mch_destroy_scrollbar() may trigger a FocusGained event. */
4654     block_autocmds();
4655 #endif
4656 
4657 #ifdef FEAT_LUA
4658     lua_window_free(wp);
4659 #endif
4660 
4661 #ifdef FEAT_MZSCHEME
4662     mzscheme_window_free(wp);
4663 #endif
4664 
4665 #ifdef FEAT_PERL
4666     perl_win_free(wp);
4667 #endif
4668 
4669 #ifdef FEAT_PYTHON
4670     python_window_free(wp);
4671 #endif
4672 
4673 #ifdef FEAT_PYTHON3
4674     python3_window_free(wp);
4675 #endif
4676 
4677 #ifdef FEAT_TCL
4678     tcl_window_free(wp);
4679 #endif
4680 
4681 #ifdef FEAT_RUBY
4682     ruby_window_free(wp);
4683 #endif
4684 
4685     clear_winopt(&wp->w_onebuf_opt);
4686     clear_winopt(&wp->w_allbuf_opt);
4687 
4688 #ifdef FEAT_EVAL
4689     vars_clear(&wp->w_vars->dv_hashtab);	/* free all w: variables */
4690     hash_init(&wp->w_vars->dv_hashtab);
4691     unref_var_dict(wp->w_vars);
4692 #endif
4693 
4694     {
4695 	tabpage_T	*ttp;
4696 
4697 	if (prevwin == wp)
4698 	    prevwin = NULL;
4699 	FOR_ALL_TABPAGES(ttp)
4700 	    if (ttp->tp_prevwin == wp)
4701 		ttp->tp_prevwin = NULL;
4702     }
4703     win_free_lsize(wp);
4704 
4705     for (i = 0; i < wp->w_tagstacklen; ++i)
4706 	vim_free(wp->w_tagstack[i].tagname);
4707 
4708     vim_free(wp->w_localdir);
4709 
4710     /* Remove the window from the b_wininfo lists, it may happen that the
4711      * freed memory is re-used for another window. */
4712     FOR_ALL_BUFFERS(buf)
4713 	for (wip = buf->b_wininfo; wip != NULL; wip = wip->wi_next)
4714 	    if (wip->wi_win == wp)
4715 		wip->wi_win = NULL;
4716 
4717 #ifdef FEAT_SEARCH_EXTRA
4718     clear_matches(wp);
4719 #endif
4720 
4721 #ifdef FEAT_JUMPLIST
4722     free_jumplist(wp);
4723 #endif
4724 
4725 #ifdef FEAT_QUICKFIX
4726     qf_free_all(wp);
4727 #endif
4728 
4729 #ifdef FEAT_GUI
4730     if (gui.in_use)
4731     {
4732 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_LEFT]);
4733 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_RIGHT]);
4734     }
4735 #endif /* FEAT_GUI */
4736 
4737 #ifdef FEAT_SYN_HL
4738     vim_free(wp->w_p_cc_cols);
4739 #endif
4740 
4741 #ifdef FEAT_AUTOCMD
4742     if (wp != aucmd_win)
4743 #endif
4744 	win_remove(wp, tp);
4745 #ifdef FEAT_AUTOCMD
4746     if (autocmd_busy)
4747     {
4748 	wp->w_next = au_pending_free_win;
4749 	au_pending_free_win = wp;
4750     }
4751     else
4752 #endif
4753 	vim_free(wp);
4754 
4755 #ifdef FEAT_AUTOCMD
4756     unblock_autocmds();
4757 #endif
4758 }
4759 
4760 /*
4761  * Append window "wp" in the window list after window "after".
4762  */
4763     void
4764 win_append(win_T *after, win_T *wp)
4765 {
4766     win_T	*before;
4767 
4768     if (after == NULL)	    /* after NULL is in front of the first */
4769 	before = firstwin;
4770     else
4771 	before = after->w_next;
4772 
4773     wp->w_next = before;
4774     wp->w_prev = after;
4775     if (after == NULL)
4776 	firstwin = wp;
4777     else
4778 	after->w_next = wp;
4779     if (before == NULL)
4780 	lastwin = wp;
4781     else
4782 	before->w_prev = wp;
4783 }
4784 
4785 /*
4786  * Remove a window from the window list.
4787  */
4788     void
4789 win_remove(
4790     win_T	*wp,
4791     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
4792 {
4793     if (wp->w_prev != NULL)
4794 	wp->w_prev->w_next = wp->w_next;
4795     else if (tp == NULL)
4796 	firstwin = wp->w_next;
4797     else
4798 	tp->tp_firstwin = wp->w_next;
4799     if (wp->w_next != NULL)
4800 	wp->w_next->w_prev = wp->w_prev;
4801     else if (tp == NULL)
4802 	lastwin = wp->w_prev;
4803     else
4804 	tp->tp_lastwin = wp->w_prev;
4805 }
4806 
4807 /*
4808  * Append frame "frp" in a frame list after frame "after".
4809  */
4810     static void
4811 frame_append(frame_T *after, frame_T *frp)
4812 {
4813     frp->fr_next = after->fr_next;
4814     after->fr_next = frp;
4815     if (frp->fr_next != NULL)
4816 	frp->fr_next->fr_prev = frp;
4817     frp->fr_prev = after;
4818 }
4819 
4820 /*
4821  * Insert frame "frp" in a frame list before frame "before".
4822  */
4823     static void
4824 frame_insert(frame_T *before, frame_T *frp)
4825 {
4826     frp->fr_next = before;
4827     frp->fr_prev = before->fr_prev;
4828     before->fr_prev = frp;
4829     if (frp->fr_prev != NULL)
4830 	frp->fr_prev->fr_next = frp;
4831     else
4832 	frp->fr_parent->fr_child = frp;
4833 }
4834 
4835 /*
4836  * Remove a frame from a frame list.
4837  */
4838     static void
4839 frame_remove(frame_T *frp)
4840 {
4841     if (frp->fr_prev != NULL)
4842 	frp->fr_prev->fr_next = frp->fr_next;
4843     else
4844 	frp->fr_parent->fr_child = frp->fr_next;
4845     if (frp->fr_next != NULL)
4846 	frp->fr_next->fr_prev = frp->fr_prev;
4847 }
4848 
4849 #endif /* FEAT_WINDOWS */
4850 
4851 /*
4852  * Allocate w_lines[] for window "wp".
4853  * Return FAIL for failure, OK for success.
4854  */
4855     int
4856 win_alloc_lines(win_T *wp)
4857 {
4858     wp->w_lines_valid = 0;
4859     wp->w_lines = (wline_T *)alloc_clear((unsigned)(Rows * sizeof(wline_T)));
4860     if (wp->w_lines == NULL)
4861 	return FAIL;
4862     return OK;
4863 }
4864 
4865 /*
4866  * free lsize arrays for a window
4867  */
4868     void
4869 win_free_lsize(win_T *wp)
4870 {
4871     /* TODO: why would wp be NULL here? */
4872     if (wp != NULL)
4873     {
4874 	vim_free(wp->w_lines);
4875 	wp->w_lines = NULL;
4876     }
4877 }
4878 
4879 /*
4880  * Called from win_new_shellsize() after Rows changed.
4881  * This only does the current tab page, others must be done when made active.
4882  */
4883     void
4884 shell_new_rows(void)
4885 {
4886     int		h = (int)ROWS_AVAIL;
4887 
4888     if (firstwin == NULL)	/* not initialized yet */
4889 	return;
4890 #ifdef FEAT_WINDOWS
4891     if (h < frame_minheight(topframe, NULL))
4892 	h = frame_minheight(topframe, NULL);
4893 
4894     /* First try setting the heights of windows with 'winfixheight'.  If
4895      * that doesn't result in the right height, forget about that option. */
4896     frame_new_height(topframe, h, FALSE, TRUE);
4897     if (!frame_check_height(topframe, h))
4898 	frame_new_height(topframe, h, FALSE, FALSE);
4899 
4900     (void)win_comp_pos();		/* recompute w_winrow and w_wincol */
4901 #else
4902     if (h < 1)
4903 	h = 1;
4904     win_new_height(firstwin, h);
4905 #endif
4906     compute_cmdrow();
4907 #ifdef FEAT_WINDOWS
4908     curtab->tp_ch_used = p_ch;
4909 #endif
4910 
4911 #if 0
4912     /* Disabled: don't want making the screen smaller make a window larger. */
4913     if (p_ea)
4914 	win_equal(curwin, FALSE, 'v');
4915 #endif
4916 }
4917 
4918 #if defined(FEAT_WINDOWS) || defined(PROTO)
4919 /*
4920  * Called from win_new_shellsize() after Columns changed.
4921  */
4922     void
4923 shell_new_columns(void)
4924 {
4925     if (firstwin == NULL)	/* not initialized yet */
4926 	return;
4927 
4928     /* First try setting the widths of windows with 'winfixwidth'.  If that
4929      * doesn't result in the right width, forget about that option. */
4930     frame_new_width(topframe, (int)Columns, FALSE, TRUE);
4931     if (!frame_check_width(topframe, Columns))
4932 	frame_new_width(topframe, (int)Columns, FALSE, FALSE);
4933 
4934     (void)win_comp_pos();		/* recompute w_winrow and w_wincol */
4935 #if 0
4936     /* Disabled: don't want making the screen smaller make a window larger. */
4937     if (p_ea)
4938 	win_equal(curwin, FALSE, 'h');
4939 #endif
4940 }
4941 #endif
4942 
4943 #if defined(FEAT_CMDWIN) || defined(PROTO)
4944 /*
4945  * Save the size of all windows in "gap".
4946  */
4947     void
4948 win_size_save(garray_T *gap)
4949 
4950 {
4951     win_T	*wp;
4952 
4953     ga_init2(gap, (int)sizeof(int), 1);
4954     if (ga_grow(gap, win_count() * 2) == OK)
4955 	FOR_ALL_WINDOWS(wp)
4956 	{
4957 	    ((int *)gap->ga_data)[gap->ga_len++] =
4958 					       wp->w_width + wp->w_vsep_width;
4959 	    ((int *)gap->ga_data)[gap->ga_len++] = wp->w_height;
4960 	}
4961 }
4962 
4963 /*
4964  * Restore window sizes, but only if the number of windows is still the same.
4965  * Does not free the growarray.
4966  */
4967     void
4968 win_size_restore(garray_T *gap)
4969 {
4970     win_T	*wp;
4971     int		i, j;
4972 
4973     if (win_count() * 2 == gap->ga_len)
4974     {
4975 	/* The order matters, because frames contain other frames, but it's
4976 	 * difficult to get right. The easy way out is to do it twice. */
4977 	for (j = 0; j < 2; ++j)
4978 	{
4979 	    i = 0;
4980 	    FOR_ALL_WINDOWS(wp)
4981 	    {
4982 		frame_setwidth(wp->w_frame, ((int *)gap->ga_data)[i++]);
4983 		win_setheight_win(((int *)gap->ga_data)[i++], wp);
4984 	    }
4985 	}
4986 	/* recompute the window positions */
4987 	(void)win_comp_pos();
4988     }
4989 }
4990 #endif /* FEAT_CMDWIN */
4991 
4992 #if defined(FEAT_WINDOWS) || defined(PROTO)
4993 /*
4994  * Update the position for all windows, using the width and height of the
4995  * frames.
4996  * Returns the row just after the last window.
4997  */
4998     int
4999 win_comp_pos(void)
5000 {
5001     int		row = tabline_height();
5002     int		col = 0;
5003 
5004     frame_comp_pos(topframe, &row, &col);
5005     return row;
5006 }
5007 
5008 /*
5009  * Update the position of the windows in frame "topfrp", using the width and
5010  * height of the frames.
5011  * "*row" and "*col" are the top-left position of the frame.  They are updated
5012  * to the bottom-right position plus one.
5013  */
5014     static void
5015 frame_comp_pos(frame_T *topfrp, int *row, int *col)
5016 {
5017     win_T	*wp;
5018     frame_T	*frp;
5019     int		startcol;
5020     int		startrow;
5021 
5022     wp = topfrp->fr_win;
5023     if (wp != NULL)
5024     {
5025 	if (wp->w_winrow != *row || wp->w_wincol != *col)
5026 	{
5027 	    /* position changed, redraw */
5028 	    wp->w_winrow = *row;
5029 	    wp->w_wincol = *col;
5030 	    redraw_win_later(wp, NOT_VALID);
5031 	    wp->w_redr_status = TRUE;
5032 	}
5033 	*row += wp->w_height + wp->w_status_height;
5034 	*col += wp->w_width + wp->w_vsep_width;
5035     }
5036     else
5037     {
5038 	startrow = *row;
5039 	startcol = *col;
5040 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
5041 	{
5042 	    if (topfrp->fr_layout == FR_ROW)
5043 		*row = startrow;	/* all frames are at the same row */
5044 	    else
5045 		*col = startcol;	/* all frames are at the same col */
5046 	    frame_comp_pos(frp, row, col);
5047 	}
5048     }
5049 }
5050 
5051 #endif /* FEAT_WINDOWS */
5052 
5053 /*
5054  * Set current window height and take care of repositioning other windows to
5055  * fit around it.
5056  */
5057     void
5058 win_setheight(int height)
5059 {
5060     win_setheight_win(height, curwin);
5061 }
5062 
5063 /*
5064  * Set the window height of window "win" and take care of repositioning other
5065  * windows to fit around it.
5066  */
5067     void
5068 win_setheight_win(int height, win_T *win)
5069 {
5070     int		row;
5071 
5072     if (win == curwin)
5073     {
5074 	/* Always keep current window at least one line high, even when
5075 	 * 'winminheight' is zero. */
5076 #ifdef FEAT_WINDOWS
5077 	if (height < p_wmh)
5078 	    height = p_wmh;
5079 #endif
5080 	if (height == 0)
5081 	    height = 1;
5082     }
5083 
5084 #ifdef FEAT_WINDOWS
5085     frame_setheight(win->w_frame, height + win->w_status_height);
5086 
5087     /* recompute the window positions */
5088     row = win_comp_pos();
5089 #else
5090     if (height > topframe->fr_height)
5091 	height = topframe->fr_height;
5092     win->w_height = height;
5093     row = height;
5094 #endif
5095 
5096     /*
5097      * If there is extra space created between the last window and the command
5098      * line, clear it.
5099      */
5100     if (full_screen && msg_scrolled == 0 && row < cmdline_row)
5101 	screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5102     cmdline_row = row;
5103     msg_row = row;
5104     msg_col = 0;
5105 
5106     redraw_all_later(NOT_VALID);
5107 }
5108 
5109 #if defined(FEAT_WINDOWS) || defined(PROTO)
5110 
5111 /*
5112  * Set the height of a frame to "height" and take care that all frames and
5113  * windows inside it are resized.  Also resize frames on the left and right if
5114  * the are in the same FR_ROW frame.
5115  *
5116  * Strategy:
5117  * If the frame is part of a FR_COL frame, try fitting the frame in that
5118  * frame.  If that doesn't work (the FR_COL frame is too small), recursively
5119  * go to containing frames to resize them and make room.
5120  * If the frame is part of a FR_ROW frame, all frames must be resized as well.
5121  * Check for the minimal height of the FR_ROW frame.
5122  * At the top level we can also use change the command line height.
5123  */
5124     static void
5125 frame_setheight(frame_T *curfrp, int height)
5126 {
5127     int		room;		/* total number of lines available */
5128     int		take;		/* number of lines taken from other windows */
5129     int		room_cmdline;	/* lines available from cmdline */
5130     int		run;
5131     frame_T	*frp;
5132     int		h;
5133     int		room_reserved;
5134 
5135     /* If the height already is the desired value, nothing to do. */
5136     if (curfrp->fr_height == height)
5137 	return;
5138 
5139     if (curfrp->fr_parent == NULL)
5140     {
5141 	/* topframe: can only change the command line */
5142 	if (height > ROWS_AVAIL)
5143 	    height = ROWS_AVAIL;
5144 	if (height > 0)
5145 	    frame_new_height(curfrp, height, FALSE, FALSE);
5146     }
5147     else if (curfrp->fr_parent->fr_layout == FR_ROW)
5148     {
5149 	/* Row of frames: Also need to resize frames left and right of this
5150 	 * one.  First check for the minimal height of these. */
5151 	h = frame_minheight(curfrp->fr_parent, NULL);
5152 	if (height < h)
5153 	    height = h;
5154 	frame_setheight(curfrp->fr_parent, height);
5155     }
5156     else
5157     {
5158 	/*
5159 	 * Column of frames: try to change only frames in this column.
5160 	 */
5161 	/*
5162 	 * Do this twice:
5163 	 * 1: compute room available, if it's not enough try resizing the
5164 	 *    containing frame.
5165 	 * 2: compute the room available and adjust the height to it.
5166 	 * Try not to reduce the height of a window with 'winfixheight' set.
5167 	 */
5168 	for (run = 1; run <= 2; ++run)
5169 	{
5170 	    room = 0;
5171 	    room_reserved = 0;
5172 	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
5173 							   frp = frp->fr_next)
5174 	    {
5175 		if (frp != curfrp
5176 			&& frp->fr_win != NULL
5177 			&& frp->fr_win->w_p_wfh)
5178 		    room_reserved += frp->fr_height;
5179 		room += frp->fr_height;
5180 		if (frp != curfrp)
5181 		    room -= frame_minheight(frp, NULL);
5182 	    }
5183 	    if (curfrp->fr_width != Columns)
5184 		room_cmdline = 0;
5185 	    else
5186 	    {
5187 		room_cmdline = Rows - p_ch - (lastwin->w_winrow
5188 			       + lastwin->w_height + lastwin->w_status_height);
5189 		if (room_cmdline < 0)
5190 		    room_cmdline = 0;
5191 	    }
5192 
5193 	    if (height <= room + room_cmdline)
5194 		break;
5195 	    if (run == 2 || curfrp->fr_width == Columns)
5196 	    {
5197 		if (height > room + room_cmdline)
5198 		    height = room + room_cmdline;
5199 		break;
5200 	    }
5201 	    frame_setheight(curfrp->fr_parent, height
5202 		+ frame_minheight(curfrp->fr_parent, NOWIN) - (int)p_wmh - 1);
5203 	}
5204 
5205 	/*
5206 	 * Compute the number of lines we will take from others frames (can be
5207 	 * negative!).
5208 	 */
5209 	take = height - curfrp->fr_height;
5210 
5211 	/* If there is not enough room, also reduce the height of a window
5212 	 * with 'winfixheight' set. */
5213 	if (height > room + room_cmdline - room_reserved)
5214 	    room_reserved = room + room_cmdline - height;
5215 	/* If there is only a 'winfixheight' window and making the
5216 	 * window smaller, need to make the other window taller. */
5217 	if (take < 0 && room - curfrp->fr_height < room_reserved)
5218 	    room_reserved = 0;
5219 
5220 	if (take > 0 && room_cmdline > 0)
5221 	{
5222 	    /* use lines from cmdline first */
5223 	    if (take < room_cmdline)
5224 		room_cmdline = take;
5225 	    take -= room_cmdline;
5226 	    topframe->fr_height += room_cmdline;
5227 	}
5228 
5229 	/*
5230 	 * set the current frame to the new height
5231 	 */
5232 	frame_new_height(curfrp, height, FALSE, FALSE);
5233 
5234 	/*
5235 	 * First take lines from the frames after the current frame.  If
5236 	 * that is not enough, takes lines from frames above the current
5237 	 * frame.
5238 	 */
5239 	for (run = 0; run < 2; ++run)
5240 	{
5241 	    if (run == 0)
5242 		frp = curfrp->fr_next;	/* 1st run: start with next window */
5243 	    else
5244 		frp = curfrp->fr_prev;	/* 2nd run: start with prev window */
5245 	    while (frp != NULL && take != 0)
5246 	    {
5247 		h = frame_minheight(frp, NULL);
5248 		if (room_reserved > 0
5249 			&& frp->fr_win != NULL
5250 			&& frp->fr_win->w_p_wfh)
5251 		{
5252 		    if (room_reserved >= frp->fr_height)
5253 			room_reserved -= frp->fr_height;
5254 		    else
5255 		    {
5256 			if (frp->fr_height - room_reserved > take)
5257 			    room_reserved = frp->fr_height - take;
5258 			take -= frp->fr_height - room_reserved;
5259 			frame_new_height(frp, room_reserved, FALSE, FALSE);
5260 			room_reserved = 0;
5261 		    }
5262 		}
5263 		else
5264 		{
5265 		    if (frp->fr_height - take < h)
5266 		    {
5267 			take -= frp->fr_height - h;
5268 			frame_new_height(frp, h, FALSE, FALSE);
5269 		    }
5270 		    else
5271 		    {
5272 			frame_new_height(frp, frp->fr_height - take,
5273 								FALSE, FALSE);
5274 			take = 0;
5275 		    }
5276 		}
5277 		if (run == 0)
5278 		    frp = frp->fr_next;
5279 		else
5280 		    frp = frp->fr_prev;
5281 	    }
5282 	}
5283     }
5284 }
5285 
5286 /*
5287  * Set current window width and take care of repositioning other windows to
5288  * fit around it.
5289  */
5290     void
5291 win_setwidth(int width)
5292 {
5293     win_setwidth_win(width, curwin);
5294 }
5295 
5296     void
5297 win_setwidth_win(int width, win_T *wp)
5298 {
5299     /* Always keep current window at least one column wide, even when
5300      * 'winminwidth' is zero. */
5301     if (wp == curwin)
5302     {
5303 	if (width < p_wmw)
5304 	    width = p_wmw;
5305 	if (width == 0)
5306 	    width = 1;
5307     }
5308 
5309     frame_setwidth(wp->w_frame, width + wp->w_vsep_width);
5310 
5311     /* recompute the window positions */
5312     (void)win_comp_pos();
5313 
5314     redraw_all_later(NOT_VALID);
5315 }
5316 
5317 /*
5318  * Set the width of a frame to "width" and take care that all frames and
5319  * windows inside it are resized.  Also resize frames above and below if the
5320  * are in the same FR_ROW frame.
5321  *
5322  * Strategy is similar to frame_setheight().
5323  */
5324     static void
5325 frame_setwidth(frame_T *curfrp, int width)
5326 {
5327     int		room;		/* total number of lines available */
5328     int		take;		/* number of lines taken from other windows */
5329     int		run;
5330     frame_T	*frp;
5331     int		w;
5332     int		room_reserved;
5333 
5334     /* If the width already is the desired value, nothing to do. */
5335     if (curfrp->fr_width == width)
5336 	return;
5337 
5338     if (curfrp->fr_parent == NULL)
5339 	/* topframe: can't change width */
5340 	return;
5341 
5342     if (curfrp->fr_parent->fr_layout == FR_COL)
5343     {
5344 	/* Column of frames: Also need to resize frames above and below of
5345 	 * this one.  First check for the minimal width of these. */
5346 	w = frame_minwidth(curfrp->fr_parent, NULL);
5347 	if (width < w)
5348 	    width = w;
5349 	frame_setwidth(curfrp->fr_parent, width);
5350     }
5351     else
5352     {
5353 	/*
5354 	 * Row of frames: try to change only frames in this row.
5355 	 *
5356 	 * Do this twice:
5357 	 * 1: compute room available, if it's not enough try resizing the
5358 	 *    containing frame.
5359 	 * 2: compute the room available and adjust the width to it.
5360 	 */
5361 	for (run = 1; run <= 2; ++run)
5362 	{
5363 	    room = 0;
5364 	    room_reserved = 0;
5365 	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
5366 							   frp = frp->fr_next)
5367 	    {
5368 		if (frp != curfrp
5369 			&& frp->fr_win != NULL
5370 			&& frp->fr_win->w_p_wfw)
5371 		    room_reserved += frp->fr_width;
5372 		room += frp->fr_width;
5373 		if (frp != curfrp)
5374 		    room -= frame_minwidth(frp, NULL);
5375 	    }
5376 
5377 	    if (width <= room)
5378 		break;
5379 	    if (run == 2 || curfrp->fr_height >= ROWS_AVAIL)
5380 	    {
5381 		if (width > room)
5382 		    width = room;
5383 		break;
5384 	    }
5385 	    frame_setwidth(curfrp->fr_parent, width
5386 		 + frame_minwidth(curfrp->fr_parent, NOWIN) - (int)p_wmw - 1);
5387 	}
5388 
5389 	/*
5390 	 * Compute the number of lines we will take from others frames (can be
5391 	 * negative!).
5392 	 */
5393 	take = width - curfrp->fr_width;
5394 
5395 	/* If there is not enough room, also reduce the width of a window
5396 	 * with 'winfixwidth' set. */
5397 	if (width > room - room_reserved)
5398 	    room_reserved = room - width;
5399 	/* If there is only a 'winfixwidth' window and making the
5400 	 * window smaller, need to make the other window narrower. */
5401 	if (take < 0 && room - curfrp->fr_width < room_reserved)
5402 	    room_reserved = 0;
5403 
5404 	/*
5405 	 * set the current frame to the new width
5406 	 */
5407 	frame_new_width(curfrp, width, FALSE, FALSE);
5408 
5409 	/*
5410 	 * First take lines from the frames right of the current frame.  If
5411 	 * that is not enough, takes lines from frames left of the current
5412 	 * frame.
5413 	 */
5414 	for (run = 0; run < 2; ++run)
5415 	{
5416 	    if (run == 0)
5417 		frp = curfrp->fr_next;	/* 1st run: start with next window */
5418 	    else
5419 		frp = curfrp->fr_prev;	/* 2nd run: start with prev window */
5420 	    while (frp != NULL && take != 0)
5421 	    {
5422 		w = frame_minwidth(frp, NULL);
5423 		if (room_reserved > 0
5424 			&& frp->fr_win != NULL
5425 			&& frp->fr_win->w_p_wfw)
5426 		{
5427 		    if (room_reserved >= frp->fr_width)
5428 			room_reserved -= frp->fr_width;
5429 		    else
5430 		    {
5431 			if (frp->fr_width - room_reserved > take)
5432 			    room_reserved = frp->fr_width - take;
5433 			take -= frp->fr_width - room_reserved;
5434 			frame_new_width(frp, room_reserved, FALSE, FALSE);
5435 			room_reserved = 0;
5436 		    }
5437 		}
5438 		else
5439 		{
5440 		    if (frp->fr_width - take < w)
5441 		    {
5442 			take -= frp->fr_width - w;
5443 			frame_new_width(frp, w, FALSE, FALSE);
5444 		    }
5445 		    else
5446 		    {
5447 			frame_new_width(frp, frp->fr_width - take,
5448 								FALSE, FALSE);
5449 			take = 0;
5450 		    }
5451 		}
5452 		if (run == 0)
5453 		    frp = frp->fr_next;
5454 		else
5455 		    frp = frp->fr_prev;
5456 	    }
5457 	}
5458     }
5459 }
5460 
5461 /*
5462  * Check 'winminheight' for a valid value.
5463  */
5464     void
5465 win_setminheight(void)
5466 {
5467     int		room;
5468     int		first = TRUE;
5469     win_T	*wp;
5470 
5471     /* loop until there is a 'winminheight' that is possible */
5472     while (p_wmh > 0)
5473     {
5474 	/* TODO: handle vertical splits */
5475 	room = -p_wh;
5476 	FOR_ALL_WINDOWS(wp)
5477 	    room += wp->w_height - p_wmh;
5478 	if (room >= 0)
5479 	    break;
5480 	--p_wmh;
5481 	if (first)
5482 	{
5483 	    EMSG(_(e_noroom));
5484 	    first = FALSE;
5485 	}
5486     }
5487 }
5488 
5489 #if defined(FEAT_MOUSE) || defined(PROTO)
5490 
5491 /*
5492  * Status line of dragwin is dragged "offset" lines down (negative is up).
5493  */
5494     void
5495 win_drag_status_line(win_T *dragwin, int offset)
5496 {
5497     frame_T	*curfr;
5498     frame_T	*fr;
5499     int		room;
5500     int		row;
5501     int		up;	/* if TRUE, drag status line up, otherwise down */
5502     int		n;
5503 
5504     fr = dragwin->w_frame;
5505     curfr = fr;
5506     if (fr != topframe)		/* more than one window */
5507     {
5508 	fr = fr->fr_parent;
5509 	/* When the parent frame is not a column of frames, its parent should
5510 	 * be. */
5511 	if (fr->fr_layout != FR_COL)
5512 	{
5513 	    curfr = fr;
5514 	    if (fr != topframe)	/* only a row of windows, may drag statusline */
5515 		fr = fr->fr_parent;
5516 	}
5517     }
5518 
5519     /* If this is the last frame in a column, may want to resize the parent
5520      * frame instead (go two up to skip a row of frames). */
5521     while (curfr != topframe && curfr->fr_next == NULL)
5522     {
5523 	if (fr != topframe)
5524 	    fr = fr->fr_parent;
5525 	curfr = fr;
5526 	if (fr != topframe)
5527 	    fr = fr->fr_parent;
5528     }
5529 
5530     if (offset < 0) /* drag up */
5531     {
5532 	up = TRUE;
5533 	offset = -offset;
5534 	/* sum up the room of the current frame and above it */
5535 	if (fr == curfr)
5536 	{
5537 	    /* only one window */
5538 	    room = fr->fr_height - frame_minheight(fr, NULL);
5539 	}
5540 	else
5541 	{
5542 	    room = 0;
5543 	    for (fr = fr->fr_child; ; fr = fr->fr_next)
5544 	    {
5545 		room += fr->fr_height - frame_minheight(fr, NULL);
5546 		if (fr == curfr)
5547 		    break;
5548 	    }
5549 	}
5550 	fr = curfr->fr_next;		/* put fr at frame that grows */
5551     }
5552     else    /* drag down */
5553     {
5554 	up = FALSE;
5555 	/*
5556 	 * Only dragging the last status line can reduce p_ch.
5557 	 */
5558 	room = Rows - cmdline_row;
5559 	if (curfr->fr_next == NULL)
5560 	    room -= 1;
5561 	else
5562 	    room -= p_ch;
5563 	if (room < 0)
5564 	    room = 0;
5565 	/* sum up the room of frames below of the current one */
5566 	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
5567 	    room += fr->fr_height - frame_minheight(fr, NULL);
5568 	fr = curfr;			/* put fr at window that grows */
5569     }
5570 
5571     if (room < offset)		/* Not enough room */
5572 	offset = room;		/* Move as far as we can */
5573     if (offset <= 0)
5574 	return;
5575 
5576     /*
5577      * Grow frame fr by "offset" lines.
5578      * Doesn't happen when dragging the last status line up.
5579      */
5580     if (fr != NULL)
5581 	frame_new_height(fr, fr->fr_height + offset, up, FALSE);
5582 
5583     if (up)
5584 	fr = curfr;		/* current frame gets smaller */
5585     else
5586 	fr = curfr->fr_next;	/* next frame gets smaller */
5587 
5588     /*
5589      * Now make the other frames smaller.
5590      */
5591     while (fr != NULL && offset > 0)
5592     {
5593 	n = frame_minheight(fr, NULL);
5594 	if (fr->fr_height - offset <= n)
5595 	{
5596 	    offset -= fr->fr_height - n;
5597 	    frame_new_height(fr, n, !up, FALSE);
5598 	}
5599 	else
5600 	{
5601 	    frame_new_height(fr, fr->fr_height - offset, !up, FALSE);
5602 	    break;
5603 	}
5604 	if (up)
5605 	    fr = fr->fr_prev;
5606 	else
5607 	    fr = fr->fr_next;
5608     }
5609     row = win_comp_pos();
5610     screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5611     cmdline_row = row;
5612     p_ch = Rows - cmdline_row;
5613     if (p_ch < 1)
5614 	p_ch = 1;
5615     curtab->tp_ch_used = p_ch;
5616     redraw_all_later(SOME_VALID);
5617     showmode();
5618 }
5619 
5620 /*
5621  * Separator line of dragwin is dragged "offset" lines right (negative is left).
5622  */
5623     void
5624 win_drag_vsep_line(win_T *dragwin, int offset)
5625 {
5626     frame_T	*curfr;
5627     frame_T	*fr;
5628     int		room;
5629     int		left;	/* if TRUE, drag separator line left, otherwise right */
5630     int		n;
5631 
5632     fr = dragwin->w_frame;
5633     if (fr == topframe)		/* only one window (cannot happen?) */
5634 	return;
5635     curfr = fr;
5636     fr = fr->fr_parent;
5637     /* When the parent frame is not a row of frames, its parent should be. */
5638     if (fr->fr_layout != FR_ROW)
5639     {
5640 	if (fr == topframe)	/* only a column of windows (cannot happen?) */
5641 	    return;
5642 	curfr = fr;
5643 	fr = fr->fr_parent;
5644     }
5645 
5646     /* If this is the last frame in a row, may want to resize a parent
5647      * frame instead. */
5648     while (curfr->fr_next == NULL)
5649     {
5650 	if (fr == topframe)
5651 	    break;
5652 	curfr = fr;
5653 	fr = fr->fr_parent;
5654 	if (fr != topframe)
5655 	{
5656 	    curfr = fr;
5657 	    fr = fr->fr_parent;
5658 	}
5659     }
5660 
5661     if (offset < 0) /* drag left */
5662     {
5663 	left = TRUE;
5664 	offset = -offset;
5665 	/* sum up the room of the current frame and left of it */
5666 	room = 0;
5667 	for (fr = fr->fr_child; ; fr = fr->fr_next)
5668 	{
5669 	    room += fr->fr_width - frame_minwidth(fr, NULL);
5670 	    if (fr == curfr)
5671 		break;
5672 	}
5673 	fr = curfr->fr_next;		/* put fr at frame that grows */
5674     }
5675     else    /* drag right */
5676     {
5677 	left = FALSE;
5678 	/* sum up the room of frames right of the current one */
5679 	room = 0;
5680 	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
5681 	    room += fr->fr_width - frame_minwidth(fr, NULL);
5682 	fr = curfr;			/* put fr at window that grows */
5683     }
5684 
5685     if (room < offset)		/* Not enough room */
5686 	offset = room;		/* Move as far as we can */
5687     if (offset <= 0)		/* No room at all, quit. */
5688 	return;
5689     if (fr == NULL)
5690 	return;			/* Safety check, should not happen. */
5691 
5692     /* grow frame fr by offset lines */
5693     frame_new_width(fr, fr->fr_width + offset, left, FALSE);
5694 
5695     /* shrink other frames: current and at the left or at the right */
5696     if (left)
5697 	fr = curfr;		/* current frame gets smaller */
5698     else
5699 	fr = curfr->fr_next;	/* next frame gets smaller */
5700 
5701     while (fr != NULL && offset > 0)
5702     {
5703 	n = frame_minwidth(fr, NULL);
5704 	if (fr->fr_width - offset <= n)
5705 	{
5706 	    offset -= fr->fr_width - n;
5707 	    frame_new_width(fr, n, !left, FALSE);
5708 	}
5709 	else
5710 	{
5711 	    frame_new_width(fr, fr->fr_width - offset, !left, FALSE);
5712 	    break;
5713 	}
5714 	if (left)
5715 	    fr = fr->fr_prev;
5716 	else
5717 	    fr = fr->fr_next;
5718     }
5719     (void)win_comp_pos();
5720     redraw_all_later(NOT_VALID);
5721 }
5722 #endif /* FEAT_MOUSE */
5723 
5724 #endif /* FEAT_WINDOWS */
5725 
5726 #define FRACTION_MULT	16384L
5727 
5728 /*
5729  * Set wp->w_fraction for the current w_wrow and w_height.
5730  */
5731     void
5732 set_fraction(win_T *wp)
5733 {
5734     wp->w_fraction = ((long)wp->w_wrow * FRACTION_MULT
5735 				    + wp->w_height / 2) / (long)wp->w_height;
5736 }
5737 
5738 /*
5739  * Set the height of a window.
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
5787 #ifdef FEAT_SCROLLBIND
5788 	    && (!wp->w_p_scb || wp == curwin)
5789 #endif
5790        )
5791     {
5792 	/*
5793 	 * Find a value for w_topline that shows the cursor at the same
5794 	 * relative position in the window as before (more or less).
5795 	 */
5796 	lnum = wp->w_cursor.lnum;
5797 	if (lnum < 1)		/* can happen when starting up */
5798 	    lnum = 1;
5799 	wp->w_wrow = ((long)wp->w_fraction * (long)height - 1L
5800 					 + FRACTION_MULT / 2) / FRACTION_MULT;
5801 	line_size = plines_win_col(wp, lnum, (long)(wp->w_cursor.col)) - 1;
5802 	sline = wp->w_wrow - line_size;
5803 
5804 	if (sline >= 0)
5805 	{
5806 	    /* Make sure the whole cursor line is visible, if possible. */
5807 	    int rows = plines_win(wp, lnum, FALSE);
5808 
5809 	    if (sline > wp->w_height - rows)
5810 	    {
5811 		sline = wp->w_height - rows;
5812 		wp->w_wrow -= rows - line_size;
5813 	    }
5814 	}
5815 
5816 	if (sline < 0)
5817 	{
5818 	    /*
5819 	     * Cursor line would go off top of screen if w_wrow was this high.
5820 	     * Make cursor line the first line in the window.  If not enough
5821 	     * room use w_skipcol;
5822 	     */
5823 	    wp->w_wrow = line_size;
5824 	    if (wp->w_wrow >= wp->w_height
5825 				       && (W_WIDTH(wp) - win_col_off(wp)) > 0)
5826 	    {
5827 		wp->w_skipcol += W_WIDTH(wp) - win_col_off(wp);
5828 		--wp->w_wrow;
5829 		while (wp->w_wrow >= wp->w_height)
5830 		{
5831 		    wp->w_skipcol += W_WIDTH(wp) - win_col_off(wp)
5832 							   + win_col_off2(wp);
5833 		    --wp->w_wrow;
5834 		}
5835 	    }
5836 	    set_topline(wp, lnum);
5837 	}
5838 	else if (sline > 0)
5839 	{
5840 	    while (sline > 0 && lnum > 1)
5841 	    {
5842 #ifdef FEAT_FOLDING
5843 		hasFoldingWin(wp, lnum, &lnum, NULL, TRUE, NULL);
5844 		if (lnum == 1)
5845 		{
5846 		    /* first line in buffer is folded */
5847 		    line_size = 1;
5848 		    --sline;
5849 		    break;
5850 		}
5851 #endif
5852 		--lnum;
5853 #ifdef FEAT_DIFF
5854 		if (lnum == wp->w_topline)
5855 		    line_size = plines_win_nofill(wp, lnum, TRUE)
5856 							      + wp->w_topfill;
5857 		else
5858 #endif
5859 		    line_size = plines_win(wp, lnum, TRUE);
5860 		sline -= line_size;
5861 	    }
5862 
5863 	    if (sline < 0)
5864 	    {
5865 		/*
5866 		 * Line we want at top would go off top of screen.  Use next
5867 		 * line instead.
5868 		 */
5869 #ifdef FEAT_FOLDING
5870 		hasFoldingWin(wp, lnum, NULL, &lnum, TRUE, NULL);
5871 #endif
5872 		lnum++;
5873 		wp->w_wrow -= line_size + sline;
5874 	    }
5875 	    else if (sline > 0)
5876 	    {
5877 		/* First line of file reached, use that as topline. */
5878 		lnum = 1;
5879 		wp->w_wrow -= sline;
5880 	    }
5881 
5882 	    set_topline(wp, lnum);
5883 	}
5884     }
5885 
5886     if (wp == curwin)
5887     {
5888 	if (p_so)
5889 	    update_topline();
5890 	curs_columns(FALSE);	/* validate w_wrow */
5891     }
5892     if (prev_height > 0)
5893 	wp->w_prev_fraction_row = wp->w_wrow;
5894 
5895     win_comp_scroll(wp);
5896     redraw_win_later(wp, SOME_VALID);
5897 #ifdef FEAT_WINDOWS
5898     wp->w_redr_status = TRUE;
5899 #endif
5900     invalidate_botline_win(wp);
5901 }
5902 
5903 #ifdef FEAT_WINDOWS
5904 /*
5905  * Set the width of a window.
5906  */
5907     void
5908 win_new_width(win_T *wp, int width)
5909 {
5910     wp->w_width = width;
5911     wp->w_lines_valid = 0;
5912     changed_line_abv_curs_win(wp);
5913     invalidate_botline_win(wp);
5914     if (wp == curwin)
5915     {
5916 	update_topline();
5917 	curs_columns(TRUE);	/* validate w_wrow */
5918     }
5919     redraw_win_later(wp, NOT_VALID);
5920     wp->w_redr_status = TRUE;
5921 }
5922 #endif
5923 
5924     void
5925 win_comp_scroll(win_T *wp)
5926 {
5927     wp->w_p_scr = ((unsigned)wp->w_height >> 1);
5928     if (wp->w_p_scr == 0)
5929 	wp->w_p_scr = 1;
5930 }
5931 
5932 /*
5933  * command_height: called whenever p_ch has been changed
5934  */
5935     void
5936 command_height(void)
5937 {
5938 #ifdef FEAT_WINDOWS
5939     int		h;
5940     frame_T	*frp;
5941     int		old_p_ch = curtab->tp_ch_used;
5942 
5943     /* Use the value of p_ch that we remembered.  This is needed for when the
5944      * GUI starts up, we can't be sure in what order things happen.  And when
5945      * p_ch was changed in another tab page. */
5946     curtab->tp_ch_used = p_ch;
5947 
5948     /* Find bottom frame with width of screen. */
5949     frp = lastwin->w_frame;
5950     while (frp->fr_width != Columns && frp->fr_parent != NULL)
5951 	frp = frp->fr_parent;
5952 
5953     /* Avoid changing the height of a window with 'winfixheight' set. */
5954     while (frp->fr_prev != NULL && frp->fr_layout == FR_LEAF
5955 						      && frp->fr_win->w_p_wfh)
5956 	frp = frp->fr_prev;
5957 
5958     if (starting != NO_SCREEN)
5959     {
5960 	cmdline_row = Rows - p_ch;
5961 
5962 	if (p_ch > old_p_ch)		    /* p_ch got bigger */
5963 	{
5964 	    while (p_ch > old_p_ch)
5965 	    {
5966 		if (frp == NULL)
5967 		{
5968 		    EMSG(_(e_noroom));
5969 		    p_ch = old_p_ch;
5970 		    curtab->tp_ch_used = p_ch;
5971 		    cmdline_row = Rows - p_ch;
5972 		    break;
5973 		}
5974 		h = frp->fr_height - frame_minheight(frp, NULL);
5975 		if (h > p_ch - old_p_ch)
5976 		    h = p_ch - old_p_ch;
5977 		old_p_ch += h;
5978 		frame_add_height(frp, -h);
5979 		frp = frp->fr_prev;
5980 	    }
5981 
5982 	    /* Recompute window positions. */
5983 	    (void)win_comp_pos();
5984 
5985 	    /* clear the lines added to cmdline */
5986 	    if (full_screen)
5987 		screen_fill((int)(cmdline_row), (int)Rows, 0,
5988 						   (int)Columns, ' ', ' ', 0);
5989 	    msg_row = cmdline_row;
5990 	    redraw_cmdline = TRUE;
5991 	    return;
5992 	}
5993 
5994 	if (msg_row < cmdline_row)
5995 	    msg_row = cmdline_row;
5996 	redraw_cmdline = TRUE;
5997     }
5998     frame_add_height(frp, (int)(old_p_ch - p_ch));
5999 
6000     /* Recompute window positions. */
6001     if (frp != lastwin->w_frame)
6002 	(void)win_comp_pos();
6003 #else
6004     cmdline_row = Rows - p_ch;
6005     win_setheight(cmdline_row);
6006 #endif
6007 }
6008 
6009 #if defined(FEAT_WINDOWS) || defined(PROTO)
6010 /*
6011  * Resize frame "frp" to be "n" lines higher (negative for less high).
6012  * Also resize the frames it is contained in.
6013  */
6014     static void
6015 frame_add_height(frame_T *frp, int n)
6016 {
6017     frame_new_height(frp, frp->fr_height + n, FALSE, FALSE);
6018     for (;;)
6019     {
6020 	frp = frp->fr_parent;
6021 	if (frp == NULL)
6022 	    break;
6023 	frp->fr_height += n;
6024     }
6025 }
6026 
6027 /*
6028  * Add or remove a status line for the bottom window(s), according to the
6029  * value of 'laststatus'.
6030  */
6031     void
6032 last_status(
6033     int		morewin)	/* pretend there are two or more windows */
6034 {
6035     /* Don't make a difference between horizontal or vertical split. */
6036     last_status_rec(topframe, (p_ls == 2
6037 			  || (p_ls == 1 && (morewin || !ONE_WINDOW))));
6038 }
6039 
6040     static void
6041 last_status_rec(frame_T *fr, int statusline)
6042 {
6043     frame_T	*fp;
6044     win_T	*wp;
6045 
6046     if (fr->fr_layout == FR_LEAF)
6047     {
6048 	wp = fr->fr_win;
6049 	if (wp->w_status_height != 0 && !statusline)
6050 	{
6051 	    /* remove status line */
6052 	    win_new_height(wp, wp->w_height + 1);
6053 	    wp->w_status_height = 0;
6054 	    comp_col();
6055 	}
6056 	else if (wp->w_status_height == 0 && statusline)
6057 	{
6058 	    /* Find a frame to take a line from. */
6059 	    fp = fr;
6060 	    while (fp->fr_height <= frame_minheight(fp, NULL))
6061 	    {
6062 		if (fp == topframe)
6063 		{
6064 		    EMSG(_(e_noroom));
6065 		    return;
6066 		}
6067 		/* In a column of frames: go to frame above.  If already at
6068 		 * the top or in a row of frames: go to parent. */
6069 		if (fp->fr_parent->fr_layout == FR_COL && fp->fr_prev != NULL)
6070 		    fp = fp->fr_prev;
6071 		else
6072 		    fp = fp->fr_parent;
6073 	    }
6074 	    wp->w_status_height = 1;
6075 	    if (fp != fr)
6076 	    {
6077 		frame_new_height(fp, fp->fr_height - 1, FALSE, FALSE);
6078 		frame_fix_height(wp);
6079 		(void)win_comp_pos();
6080 	    }
6081 	    else
6082 		win_new_height(wp, wp->w_height - 1);
6083 	    comp_col();
6084 	    redraw_all_later(SOME_VALID);
6085 	}
6086     }
6087     else if (fr->fr_layout == FR_ROW)
6088     {
6089 	/* vertically split windows, set status line for each one */
6090 	for (fp = fr->fr_child; fp != NULL; fp = fp->fr_next)
6091 	    last_status_rec(fp, statusline);
6092     }
6093     else
6094     {
6095 	/* horizontally split window, set status line for last one */
6096 	for (fp = fr->fr_child; fp->fr_next != NULL; fp = fp->fr_next)
6097 	    ;
6098 	last_status_rec(fp, statusline);
6099     }
6100 }
6101 
6102 /*
6103  * Return the number of lines used by the tab page line.
6104  */
6105     int
6106 tabline_height(void)
6107 {
6108 #ifdef FEAT_GUI_TABLINE
6109     /* When the GUI has the tabline then this always returns zero. */
6110     if (gui_use_tabline())
6111 	return 0;
6112 #endif
6113     switch (p_stal)
6114     {
6115 	case 0: return 0;
6116 	case 1: return (first_tabpage->tp_next == NULL) ? 0 : 1;
6117     }
6118     return 1;
6119 }
6120 
6121 #endif /* FEAT_WINDOWS */
6122 
6123 #if defined(FEAT_SEARCHPATH) || defined(PROTO)
6124 /*
6125  * Get the file name at the cursor.
6126  * If Visual mode is active, use the selected text if it's in one line.
6127  * Returns the name in allocated memory, NULL for failure.
6128  */
6129     char_u *
6130 grab_file_name(long count, linenr_T *file_lnum)
6131 {
6132     int options = FNAME_MESS|FNAME_EXP|FNAME_REL|FNAME_UNESC;
6133 
6134     if (VIsual_active)
6135     {
6136 	int	len;
6137 	char_u	*ptr;
6138 
6139 	if (get_visual_text(NULL, &ptr, &len) == FAIL)
6140 	    return NULL;
6141 	return find_file_name_in_path(ptr, len, options,
6142 						     count, curbuf->b_ffname);
6143     }
6144     return file_name_at_cursor(options | FNAME_HYP, count, file_lnum);
6145 
6146 }
6147 
6148 /*
6149  * Return the file name under or after the cursor.
6150  *
6151  * The 'path' option is searched if the file name is not absolute.
6152  * The string returned has been alloc'ed and should be freed by the caller.
6153  * NULL is returned if the file name or file is not found.
6154  *
6155  * options:
6156  * FNAME_MESS	    give error messages
6157  * FNAME_EXP	    expand to path
6158  * FNAME_HYP	    check for hypertext link
6159  * FNAME_INCL	    apply "includeexpr"
6160  */
6161     char_u *
6162 file_name_at_cursor(int options, long count, linenr_T *file_lnum)
6163 {
6164     return file_name_in_line(ml_get_curline(),
6165 		      curwin->w_cursor.col, options, count, curbuf->b_ffname,
6166 		      file_lnum);
6167 }
6168 
6169 /*
6170  * Return the name of the file under or after ptr[col].
6171  * Otherwise like file_name_at_cursor().
6172  */
6173     char_u *
6174 file_name_in_line(
6175     char_u	*line,
6176     int		col,
6177     int		options,
6178     long	count,
6179     char_u	*rel_fname,	/* file we are searching relative to */
6180     linenr_T	*file_lnum)	/* line number after the file name */
6181 {
6182     char_u	*ptr;
6183     int		len;
6184 
6185     /*
6186      * search forward for what could be the start of a file name
6187      */
6188     ptr = line + col;
6189     while (*ptr != NUL && !vim_isfilec(*ptr))
6190 	MB_PTR_ADV(ptr);
6191     if (*ptr == NUL)		/* nothing found */
6192     {
6193 	if (options & FNAME_MESS)
6194 	    EMSG(_("E446: No file name under cursor"));
6195 	return NULL;
6196     }
6197 
6198     /*
6199      * Search backward for first char of the file name.
6200      * Go one char back to ":" before "//" even when ':' is not in 'isfname'.
6201      */
6202     while (ptr > line)
6203     {
6204 #ifdef FEAT_MBYTE
6205 	if (has_mbyte && (len = (*mb_head_off)(line, ptr - 1)) > 0)
6206 	    ptr -= len + 1;
6207 	else
6208 #endif
6209 	if (vim_isfilec(ptr[-1])
6210 		|| ((options & FNAME_HYP) && path_is_url(ptr - 1)))
6211 	    --ptr;
6212 	else
6213 	    break;
6214     }
6215 
6216     /*
6217      * Search forward for the last char of the file name.
6218      * Also allow "://" when ':' is not in 'isfname'.
6219      */
6220     len = 0;
6221     while (vim_isfilec(ptr[len]) || (ptr[len] == '\\' && ptr[len + 1] == ' ')
6222 			 || ((options & FNAME_HYP) && path_is_url(ptr + len)))
6223     {
6224 	if (ptr[len] == '\\')
6225 	    /* Skip over the "\" in "\ ". */
6226 	    ++len;
6227 #ifdef FEAT_MBYTE
6228 	if (has_mbyte)
6229 	    len += (*mb_ptr2len)(ptr + len);
6230 	else
6231 #endif
6232 	    ++len;
6233     }
6234 
6235     /*
6236      * If there is trailing punctuation, remove it.
6237      * But don't remove "..", could be a directory name.
6238      */
6239     if (len > 2 && vim_strchr((char_u *)".,:;!", ptr[len - 1]) != NULL
6240 						       && ptr[len - 2] != '.')
6241 	--len;
6242 
6243     if (file_lnum != NULL)
6244     {
6245 	char_u *p;
6246 
6247 	/* Get the number after the file name and a separator character */
6248 	p = ptr + len;
6249 	p = skipwhite(p);
6250 	if (*p != NUL)
6251 	{
6252 	    if (!isdigit(*p))
6253 		++p;		    /* skip the separator */
6254 	    p = skipwhite(p);
6255 	    if (isdigit(*p))
6256 		*file_lnum = (int)getdigits(&p);
6257 	}
6258     }
6259 
6260     return find_file_name_in_path(ptr, len, options, count, rel_fname);
6261 }
6262 
6263 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6264 static char_u *eval_includeexpr(char_u *ptr, int len);
6265 
6266     static char_u *
6267 eval_includeexpr(char_u *ptr, int len)
6268 {
6269     char_u	*res;
6270 
6271     set_vim_var_string(VV_FNAME, ptr, len);
6272     res = eval_to_string_safe(curbuf->b_p_inex, NULL,
6273 		      was_set_insecurely((char_u *)"includeexpr", OPT_LOCAL));
6274     set_vim_var_string(VV_FNAME, NULL, 0);
6275     return res;
6276 }
6277 #endif
6278 
6279 /*
6280  * Return the name of the file ptr[len] in 'path'.
6281  * Otherwise like file_name_at_cursor().
6282  */
6283     char_u *
6284 find_file_name_in_path(
6285     char_u	*ptr,
6286     int		len,
6287     int		options,
6288     long	count,
6289     char_u	*rel_fname)	/* file we are searching relative to */
6290 {
6291     char_u	*file_name;
6292     int		c;
6293 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6294     char_u	*tofree = NULL;
6295 
6296     if ((options & FNAME_INCL) && *curbuf->b_p_inex != NUL)
6297     {
6298 	tofree = eval_includeexpr(ptr, len);
6299 	if (tofree != NULL)
6300 	{
6301 	    ptr = tofree;
6302 	    len = (int)STRLEN(ptr);
6303 	}
6304     }
6305 # endif
6306 
6307     if (options & FNAME_EXP)
6308     {
6309 	file_name = find_file_in_path(ptr, len, options & ~FNAME_MESS,
6310 							     TRUE, rel_fname);
6311 
6312 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6313 	/*
6314 	 * If the file could not be found in a normal way, try applying
6315 	 * 'includeexpr' (unless done already).
6316 	 */
6317 	if (file_name == NULL
6318 		&& !(options & FNAME_INCL) && *curbuf->b_p_inex != NUL)
6319 	{
6320 	    tofree = eval_includeexpr(ptr, len);
6321 	    if (tofree != NULL)
6322 	    {
6323 		ptr = tofree;
6324 		len = (int)STRLEN(ptr);
6325 		file_name = find_file_in_path(ptr, len, options & ~FNAME_MESS,
6326 							     TRUE, rel_fname);
6327 	    }
6328 	}
6329 # endif
6330 	if (file_name == NULL && (options & FNAME_MESS))
6331 	{
6332 	    c = ptr[len];
6333 	    ptr[len] = NUL;
6334 	    EMSG2(_("E447: Can't find file \"%s\" in path"), ptr);
6335 	    ptr[len] = c;
6336 	}
6337 
6338 	/* Repeat finding the file "count" times.  This matters when it
6339 	 * appears several times in the path. */
6340 	while (file_name != NULL && --count > 0)
6341 	{
6342 	    vim_free(file_name);
6343 	    file_name = find_file_in_path(ptr, len, options, FALSE, rel_fname);
6344 	}
6345     }
6346     else
6347 	file_name = vim_strnsave(ptr, len);
6348 
6349 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6350     vim_free(tofree);
6351 # endif
6352 
6353     return file_name;
6354 }
6355 #endif /* FEAT_SEARCHPATH */
6356 
6357 /*
6358  * Check if the "://" of a URL is at the pointer, return URL_SLASH.
6359  * Also check for ":\\", which MS Internet Explorer accepts, return
6360  * URL_BACKSLASH.
6361  */
6362     static int
6363 path_is_url(char_u *p)
6364 {
6365     if (STRNCMP(p, "://", (size_t)3) == 0)
6366 	return URL_SLASH;
6367     else if (STRNCMP(p, ":\\\\", (size_t)3) == 0)
6368 	return URL_BACKSLASH;
6369     return 0;
6370 }
6371 
6372 /*
6373  * Check if "fname" starts with "name://".  Return URL_SLASH if it does.
6374  * Return URL_BACKSLASH for "name:\\".
6375  * Return zero otherwise.
6376  */
6377     int
6378 path_with_url(char_u *fname)
6379 {
6380     char_u *p;
6381 
6382     for (p = fname; isalpha(*p); ++p)
6383 	;
6384     return path_is_url(p);
6385 }
6386 
6387 /*
6388  * Return TRUE if "name" is a full (absolute) path name or URL.
6389  */
6390     int
6391 vim_isAbsName(char_u *name)
6392 {
6393     return (path_with_url(name) != 0 || mch_isFullName(name));
6394 }
6395 
6396 /*
6397  * Get absolute file name into buffer "buf[len]".
6398  *
6399  * return FAIL for failure, OK otherwise
6400  */
6401     int
6402 vim_FullName(
6403     char_u	*fname,
6404     char_u	*buf,
6405     int		len,
6406     int		force)	    /* force expansion even when already absolute */
6407 {
6408     int		retval = OK;
6409     int		url;
6410 
6411     *buf = NUL;
6412     if (fname == NULL)
6413 	return FAIL;
6414 
6415     url = path_with_url(fname);
6416     if (!url)
6417 	retval = mch_FullName(fname, buf, len, force);
6418     if (url || retval == FAIL)
6419     {
6420 	/* something failed; use the file name (truncate when too long) */
6421 	vim_strncpy(buf, fname, len - 1);
6422     }
6423 #if defined(MACOS_CLASSIC) || defined(MSWIN)
6424     slash_adjust(buf);
6425 #endif
6426     return retval;
6427 }
6428 
6429 /*
6430  * Return the minimal number of rows that is needed on the screen to display
6431  * the current number of windows.
6432  */
6433     int
6434 min_rows(void)
6435 {
6436     int		total;
6437 #ifdef FEAT_WINDOWS
6438     tabpage_T	*tp;
6439     int		n;
6440 #endif
6441 
6442     if (firstwin == NULL)	/* not initialized yet */
6443 	return MIN_LINES;
6444 
6445 #ifdef FEAT_WINDOWS
6446     total = 0;
6447     FOR_ALL_TABPAGES(tp)
6448     {
6449 	n = frame_minheight(tp->tp_topframe, NULL);
6450 	if (total < n)
6451 	    total = n;
6452     }
6453     total += tabline_height();
6454 #else
6455     total = 1;		/* at least one window should have a line! */
6456 #endif
6457     total += 1;		/* count the room for the command line */
6458     return total;
6459 }
6460 
6461 /*
6462  * Return TRUE if there is only one window (in the current tab page), not
6463  * counting a help or preview window, unless it is the current window.
6464  * Does not count "aucmd_win".
6465  */
6466     int
6467 only_one_window(void)
6468 {
6469 #ifdef FEAT_WINDOWS
6470     int		count = 0;
6471     win_T	*wp;
6472 
6473     /* If there is another tab page there always is another window. */
6474     if (first_tabpage->tp_next != NULL)
6475 	return FALSE;
6476 
6477     FOR_ALL_WINDOWS(wp)
6478 	if (wp->w_buffer != NULL
6479 		&& (!((wp->w_buffer->b_help && !curbuf->b_help)
6480 # ifdef FEAT_QUICKFIX
6481 		    || wp->w_p_pvw
6482 # endif
6483 	     ) || wp == curwin)
6484 # ifdef FEAT_AUTOCMD
6485 		&& wp != aucmd_win
6486 # endif
6487 	   )
6488 	    ++count;
6489     return (count <= 1);
6490 #else
6491     return TRUE;
6492 #endif
6493 }
6494 
6495 #if defined(FEAT_WINDOWS) || defined(FEAT_AUTOCMD) || defined(PROTO)
6496 /*
6497  * Correct the cursor line number in other windows.  Used after changing the
6498  * current buffer, and before applying autocommands.
6499  * When "do_curwin" is TRUE, also check current window.
6500  */
6501     void
6502 check_lnums(int do_curwin)
6503 {
6504     win_T	*wp;
6505 
6506 #ifdef FEAT_WINDOWS
6507     tabpage_T	*tp;
6508 
6509     FOR_ALL_TAB_WINDOWS(tp, wp)
6510 	if ((do_curwin || wp != curwin) && wp->w_buffer == curbuf)
6511 #else
6512     wp = curwin;
6513     if (do_curwin)
6514 #endif
6515 	{
6516 	    if (wp->w_cursor.lnum > curbuf->b_ml.ml_line_count)
6517 		wp->w_cursor.lnum = curbuf->b_ml.ml_line_count;
6518 	    if (wp->w_topline > curbuf->b_ml.ml_line_count)
6519 		wp->w_topline = curbuf->b_ml.ml_line_count;
6520 	}
6521 }
6522 #endif
6523 
6524 #if defined(FEAT_WINDOWS) || defined(PROTO)
6525 
6526 /*
6527  * A snapshot of the window sizes, to restore them after closing the help
6528  * window.
6529  * Only these fields are used:
6530  * fr_layout
6531  * fr_width
6532  * fr_height
6533  * fr_next
6534  * fr_child
6535  * fr_win (only valid for the old curwin, NULL otherwise)
6536  */
6537 
6538 /*
6539  * Create a snapshot of the current frame sizes.
6540  */
6541     void
6542 make_snapshot(int idx)
6543 {
6544     clear_snapshot(curtab, idx);
6545     make_snapshot_rec(topframe, &curtab->tp_snapshot[idx]);
6546 }
6547 
6548     static void
6549 make_snapshot_rec(frame_T *fr, frame_T **frp)
6550 {
6551     *frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
6552     if (*frp == NULL)
6553 	return;
6554     (*frp)->fr_layout = fr->fr_layout;
6555     (*frp)->fr_width = fr->fr_width;
6556     (*frp)->fr_height = fr->fr_height;
6557     if (fr->fr_next != NULL)
6558 	make_snapshot_rec(fr->fr_next, &((*frp)->fr_next));
6559     if (fr->fr_child != NULL)
6560 	make_snapshot_rec(fr->fr_child, &((*frp)->fr_child));
6561     if (fr->fr_layout == FR_LEAF && fr->fr_win == curwin)
6562 	(*frp)->fr_win = curwin;
6563 }
6564 
6565 /*
6566  * Remove any existing snapshot.
6567  */
6568     static void
6569 clear_snapshot(tabpage_T *tp, int idx)
6570 {
6571     clear_snapshot_rec(tp->tp_snapshot[idx]);
6572     tp->tp_snapshot[idx] = NULL;
6573 }
6574 
6575     static void
6576 clear_snapshot_rec(frame_T *fr)
6577 {
6578     if (fr != NULL)
6579     {
6580 	clear_snapshot_rec(fr->fr_next);
6581 	clear_snapshot_rec(fr->fr_child);
6582 	vim_free(fr);
6583     }
6584 }
6585 
6586 /*
6587  * Restore a previously created snapshot, if there is any.
6588  * This is only done if the screen size didn't change and the window layout is
6589  * still the same.
6590  */
6591     void
6592 restore_snapshot(
6593     int		idx,
6594     int		close_curwin)	    /* closing current window */
6595 {
6596     win_T	*wp;
6597 
6598     if (curtab->tp_snapshot[idx] != NULL
6599 	    && curtab->tp_snapshot[idx]->fr_width == topframe->fr_width
6600 	    && curtab->tp_snapshot[idx]->fr_height == topframe->fr_height
6601 	    && check_snapshot_rec(curtab->tp_snapshot[idx], topframe) == OK)
6602     {
6603 	wp = restore_snapshot_rec(curtab->tp_snapshot[idx], topframe);
6604 	win_comp_pos();
6605 	if (wp != NULL && close_curwin)
6606 	    win_goto(wp);
6607 	redraw_all_later(CLEAR);
6608     }
6609     clear_snapshot(curtab, idx);
6610 }
6611 
6612 /*
6613  * Check if frames "sn" and "fr" have the same layout, same following frames
6614  * and same children.  And the window pointer is valid.
6615  */
6616     static int
6617 check_snapshot_rec(frame_T *sn, frame_T *fr)
6618 {
6619     if (sn->fr_layout != fr->fr_layout
6620 	    || (sn->fr_next == NULL) != (fr->fr_next == NULL)
6621 	    || (sn->fr_child == NULL) != (fr->fr_child == NULL)
6622 	    || (sn->fr_next != NULL
6623 		&& check_snapshot_rec(sn->fr_next, fr->fr_next) == FAIL)
6624 	    || (sn->fr_child != NULL
6625 		&& check_snapshot_rec(sn->fr_child, fr->fr_child) == FAIL)
6626 	    || (sn->fr_win != NULL && !win_valid(sn->fr_win)))
6627 	return FAIL;
6628     return OK;
6629 }
6630 
6631 /*
6632  * Copy the size of snapshot frame "sn" to frame "fr".  Do the same for all
6633  * following frames and children.
6634  * Returns a pointer to the old current window, or NULL.
6635  */
6636     static win_T *
6637 restore_snapshot_rec(frame_T *sn, frame_T *fr)
6638 {
6639     win_T	*wp = NULL;
6640     win_T	*wp2;
6641 
6642     fr->fr_height = sn->fr_height;
6643     fr->fr_width = sn->fr_width;
6644     if (fr->fr_layout == FR_LEAF)
6645     {
6646 	frame_new_height(fr, fr->fr_height, FALSE, FALSE);
6647 	frame_new_width(fr, fr->fr_width, FALSE, FALSE);
6648 	wp = sn->fr_win;
6649     }
6650     if (sn->fr_next != NULL)
6651     {
6652 	wp2 = restore_snapshot_rec(sn->fr_next, fr->fr_next);
6653 	if (wp2 != NULL)
6654 	    wp = wp2;
6655     }
6656     if (sn->fr_child != NULL)
6657     {
6658 	wp2 = restore_snapshot_rec(sn->fr_child, fr->fr_child);
6659 	if (wp2 != NULL)
6660 	    wp = wp2;
6661     }
6662     return wp;
6663 }
6664 
6665 #endif
6666 
6667 #if defined(FEAT_EVAL) || defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) \
6668 	|| defined(PROTO)
6669 /*
6670  * Set "win" to be the curwin and "tp" to be the current tab page.
6671  * restore_win() MUST be called to undo, also when FAIL is returned.
6672  * No autocommands will be executed until restore_win() is called.
6673  * When "no_display" is TRUE the display won't be affected, no redraw is
6674  * triggered, another tabpage access is limited.
6675  * Returns FAIL if switching to "win" failed.
6676  */
6677     int
6678 switch_win(
6679     win_T	**save_curwin UNUSED,
6680     tabpage_T	**save_curtab UNUSED,
6681     win_T	*win UNUSED,
6682     tabpage_T	*tp UNUSED,
6683     int		no_display UNUSED)
6684 {
6685 # ifdef FEAT_AUTOCMD
6686     block_autocmds();
6687 # endif
6688 # ifdef FEAT_WINDOWS
6689     *save_curwin = curwin;
6690     if (tp != NULL)
6691     {
6692 	*save_curtab = curtab;
6693 	if (no_display)
6694 	{
6695 	    curtab->tp_firstwin = firstwin;
6696 	    curtab->tp_lastwin = lastwin;
6697 	    curtab = tp;
6698 	    firstwin = curtab->tp_firstwin;
6699 	    lastwin = curtab->tp_lastwin;
6700 	}
6701 	else
6702 	    goto_tabpage_tp(tp, FALSE, FALSE);
6703     }
6704     if (!win_valid(win))
6705 	return FAIL;
6706     curwin = win;
6707     curbuf = curwin->w_buffer;
6708 # endif
6709     return OK;
6710 }
6711 
6712 /*
6713  * Restore current tabpage and window saved by switch_win(), if still valid.
6714  * When "no_display" is TRUE the display won't be affected, no redraw is
6715  * triggered.
6716  */
6717     void
6718 restore_win(
6719     win_T	*save_curwin UNUSED,
6720     tabpage_T	*save_curtab UNUSED,
6721     int		no_display UNUSED)
6722 {
6723 # ifdef FEAT_WINDOWS
6724     if (save_curtab != NULL && valid_tabpage(save_curtab))
6725     {
6726 	if (no_display)
6727 	{
6728 	    curtab->tp_firstwin = firstwin;
6729 	    curtab->tp_lastwin = lastwin;
6730 	    curtab = save_curtab;
6731 	    firstwin = curtab->tp_firstwin;
6732 	    lastwin = curtab->tp_lastwin;
6733 	}
6734 	else
6735 	    goto_tabpage_tp(save_curtab, FALSE, FALSE);
6736     }
6737     if (win_valid(save_curwin))
6738     {
6739 	curwin = save_curwin;
6740 	curbuf = curwin->w_buffer;
6741     }
6742 # endif
6743 # ifdef FEAT_AUTOCMD
6744     unblock_autocmds();
6745 # endif
6746 }
6747 
6748 /*
6749  * Make "buf" the current buffer.  restore_buffer() MUST be called to undo.
6750  * No autocommands will be executed.  Use aucmd_prepbuf() if there are any.
6751  */
6752     void
6753 switch_buffer(bufref_T *save_curbuf, buf_T *buf)
6754 {
6755 # ifdef FEAT_AUTOCMD
6756     block_autocmds();
6757 # endif
6758     set_bufref(save_curbuf, curbuf);
6759     --curbuf->b_nwindows;
6760     curbuf = buf;
6761     curwin->w_buffer = buf;
6762     ++curbuf->b_nwindows;
6763 }
6764 
6765 /*
6766  * Restore the current buffer after using switch_buffer().
6767  */
6768     void
6769 restore_buffer(bufref_T *save_curbuf)
6770 {
6771 # ifdef FEAT_AUTOCMD
6772     unblock_autocmds();
6773 # endif
6774     /* Check for valid buffer, just in case. */
6775     if (bufref_valid(save_curbuf))
6776     {
6777 	--curbuf->b_nwindows;
6778 	curwin->w_buffer = save_curbuf->br_buf;
6779 	curbuf = save_curbuf->br_buf;
6780 	++curbuf->b_nwindows;
6781     }
6782 }
6783 #endif
6784 
6785 #if (defined(FEAT_GUI) && defined(FEAT_WINDOWS)) || defined(PROTO)
6786 /*
6787  * Return TRUE if there is any vertically split window.
6788  */
6789     int
6790 win_hasvertsplit(void)
6791 {
6792     frame_T	*fr;
6793 
6794     if (topframe->fr_layout == FR_ROW)
6795 	return TRUE;
6796 
6797     if (topframe->fr_layout == FR_COL)
6798 	for (fr = topframe->fr_child; fr != NULL; fr = fr->fr_next)
6799 	    if (fr->fr_layout == FR_ROW)
6800 		return TRUE;
6801 
6802     return FALSE;
6803 }
6804 #endif
6805 
6806 #if defined(FEAT_SEARCH_EXTRA) || defined(PROTO)
6807 /*
6808  * Add match to the match list of window 'wp'.  The pattern 'pat' will be
6809  * highlighted with the group 'grp' with priority 'prio'.
6810  * Optionally, a desired ID 'id' can be specified (greater than or equal to 1).
6811  * If no particular ID is desired, -1 must be specified for 'id'.
6812  * Return ID of added match, -1 on failure.
6813  */
6814     int
6815 match_add(
6816     win_T	*wp,
6817     char_u	*grp,
6818     char_u	*pat,
6819     int		prio,
6820     int		id,
6821     list_T	*pos_list,
6822     char_u      *conceal_char UNUSED) /* pointer to conceal replacement char */
6823 {
6824     matchitem_T	*cur;
6825     matchitem_T	*prev;
6826     matchitem_T	*m;
6827     int		hlg_id;
6828     regprog_T	*regprog = NULL;
6829     int		rtype = SOME_VALID;
6830 
6831     if (*grp == NUL || (pat != NULL && *pat == NUL))
6832 	return -1;
6833     if (id < -1 || id == 0)
6834     {
6835 	EMSGN(_("E799: Invalid ID: %ld (must be greater than or equal to 1)"), id);
6836 	return -1;
6837     }
6838     if (id != -1)
6839     {
6840 	cur = wp->w_match_head;
6841 	while (cur != NULL)
6842 	{
6843 	    if (cur->id == id)
6844 	    {
6845 		EMSGN(_("E801: ID already taken: %ld"), id);
6846 		return -1;
6847 	    }
6848 	    cur = cur->next;
6849 	}
6850     }
6851     if ((hlg_id = syn_namen2id(grp, (int)STRLEN(grp))) == 0)
6852     {
6853 	EMSG2(_(e_nogroup), grp);
6854 	return -1;
6855     }
6856     if (pat != NULL && (regprog = vim_regcomp(pat, RE_MAGIC)) == NULL)
6857     {
6858 	EMSG2(_(e_invarg2), pat);
6859 	return -1;
6860     }
6861 
6862     /* Find available match ID. */
6863     while (id == -1)
6864     {
6865 	cur = wp->w_match_head;
6866 	while (cur != NULL && cur->id != wp->w_next_match_id)
6867 	    cur = cur->next;
6868 	if (cur == NULL)
6869 	    id = wp->w_next_match_id;
6870 	wp->w_next_match_id++;
6871     }
6872 
6873     /* Build new match. */
6874     m = (matchitem_T *)alloc_clear(sizeof(matchitem_T));
6875     m->id = id;
6876     m->priority = prio;
6877     m->pattern = pat == NULL ? NULL : vim_strsave(pat);
6878     m->hlg_id = hlg_id;
6879     m->match.regprog = regprog;
6880     m->match.rmm_ic = FALSE;
6881     m->match.rmm_maxcol = 0;
6882 # if defined(FEAT_CONCEAL) && defined(FEAT_MBYTE)
6883     m->conceal_char = 0;
6884     if (conceal_char != NULL)
6885 	m->conceal_char = (*mb_ptr2char)(conceal_char);
6886 # endif
6887 
6888     /* Set up position matches */
6889     if (pos_list != NULL)
6890     {
6891 	linenr_T	toplnum = 0;
6892 	linenr_T	botlnum = 0;
6893 	listitem_T	*li;
6894 	int		i;
6895 
6896 	for (i = 0, li = pos_list->lv_first; li != NULL && i < MAXPOSMATCH;
6897 							i++, li = li->li_next)
6898 	{
6899 	    linenr_T	lnum = 0;
6900 	    colnr_T	col = 0;
6901 	    int		len = 1;
6902 	    list_T	*subl;
6903 	    listitem_T	*subli;
6904 	    int		error = FALSE;
6905 
6906 	    if (li->li_tv.v_type == VAR_LIST)
6907 	    {
6908 		subl = li->li_tv.vval.v_list;
6909 		if (subl == NULL)
6910 		    goto fail;
6911 		subli = subl->lv_first;
6912 		if (subli == NULL)
6913 		    goto fail;
6914 		lnum = get_tv_number_chk(&subli->li_tv, &error);
6915 		if (error == TRUE)
6916 		    goto fail;
6917 		if (lnum == 0)
6918 		{
6919 		    --i;
6920 		    continue;
6921 		}
6922 		m->pos.pos[i].lnum = lnum;
6923 		subli = subli->li_next;
6924 		if (subli != NULL)
6925 		{
6926 		    col = get_tv_number_chk(&subli->li_tv, &error);
6927 		    if (error == TRUE)
6928 			goto fail;
6929 		    subli = subli->li_next;
6930 		    if (subli != NULL)
6931 		    {
6932 			len = get_tv_number_chk(&subli->li_tv, &error);
6933 			if (error == TRUE)
6934 			    goto fail;
6935 		    }
6936 		}
6937 		m->pos.pos[i].col = col;
6938 		m->pos.pos[i].len = len;
6939 	    }
6940 	    else if (li->li_tv.v_type == VAR_NUMBER)
6941 	    {
6942 		if (li->li_tv.vval.v_number == 0)
6943 		{
6944 		    --i;
6945 		    continue;
6946 		}
6947 		m->pos.pos[i].lnum = li->li_tv.vval.v_number;
6948 		m->pos.pos[i].col = 0;
6949 		m->pos.pos[i].len = 0;
6950 	    }
6951 	    else
6952 	    {
6953 		EMSG(_("List or number required"));
6954 		goto fail;
6955 	    }
6956 	    if (toplnum == 0 || lnum < toplnum)
6957 		toplnum = lnum;
6958 	    if (botlnum == 0 || lnum >= botlnum)
6959 		botlnum = lnum + 1;
6960 	}
6961 
6962 	/* Calculate top and bottom lines for redrawing area */
6963 	if (toplnum != 0)
6964 	{
6965 	    if (wp->w_buffer->b_mod_set)
6966 	    {
6967 		if (wp->w_buffer->b_mod_top > toplnum)
6968 		    wp->w_buffer->b_mod_top = toplnum;
6969 		if (wp->w_buffer->b_mod_bot < botlnum)
6970 		    wp->w_buffer->b_mod_bot = botlnum;
6971 	    }
6972 	    else
6973 	    {
6974 		wp->w_buffer->b_mod_set = TRUE;
6975 		wp->w_buffer->b_mod_top = toplnum;
6976 		wp->w_buffer->b_mod_bot = botlnum;
6977 		wp->w_buffer->b_mod_xlines = 0;
6978 	    }
6979 	    m->pos.toplnum = toplnum;
6980 	    m->pos.botlnum = botlnum;
6981 	    rtype = VALID;
6982 	}
6983     }
6984 
6985     /* Insert new match.  The match list is in ascending order with regard to
6986      * the match priorities. */
6987     cur = wp->w_match_head;
6988     prev = cur;
6989     while (cur != NULL && prio >= cur->priority)
6990     {
6991 	prev = cur;
6992 	cur = cur->next;
6993     }
6994     if (cur == prev)
6995 	wp->w_match_head = m;
6996     else
6997 	prev->next = m;
6998     m->next = cur;
6999 
7000     redraw_later(rtype);
7001     return id;
7002 
7003 fail:
7004     vim_free(m);
7005     return -1;
7006 }
7007 
7008 /*
7009  * Delete match with ID 'id' in the match list of window 'wp'.
7010  * Print error messages if 'perr' is TRUE.
7011  */
7012     int
7013 match_delete(win_T *wp, int id, int perr)
7014 {
7015     matchitem_T	*cur = wp->w_match_head;
7016     matchitem_T	*prev = cur;
7017     int		rtype = SOME_VALID;
7018 
7019     if (id < 1)
7020     {
7021 	if (perr == TRUE)
7022 	    EMSGN(_("E802: Invalid ID: %ld (must be greater than or equal to 1)"),
7023 									  id);
7024 	return -1;
7025     }
7026     while (cur != NULL && cur->id != id)
7027     {
7028 	prev = cur;
7029 	cur = cur->next;
7030     }
7031     if (cur == NULL)
7032     {
7033 	if (perr == TRUE)
7034 	    EMSGN(_("E803: ID not found: %ld"), id);
7035 	return -1;
7036     }
7037     if (cur == prev)
7038 	wp->w_match_head = cur->next;
7039     else
7040 	prev->next = cur->next;
7041     vim_regfree(cur->match.regprog);
7042     vim_free(cur->pattern);
7043     if (cur->pos.toplnum != 0)
7044     {
7045 	if (wp->w_buffer->b_mod_set)
7046 	{
7047 	    if (wp->w_buffer->b_mod_top > cur->pos.toplnum)
7048 		wp->w_buffer->b_mod_top = cur->pos.toplnum;
7049 	    if (wp->w_buffer->b_mod_bot < cur->pos.botlnum)
7050 		wp->w_buffer->b_mod_bot = cur->pos.botlnum;
7051 	}
7052 	else
7053 	{
7054 	    wp->w_buffer->b_mod_set = TRUE;
7055 	    wp->w_buffer->b_mod_top = cur->pos.toplnum;
7056 	    wp->w_buffer->b_mod_bot = cur->pos.botlnum;
7057 	    wp->w_buffer->b_mod_xlines = 0;
7058 	}
7059 	rtype = VALID;
7060     }
7061     vim_free(cur);
7062     redraw_later(rtype);
7063     return 0;
7064 }
7065 
7066 /*
7067  * Delete all matches in the match list of window 'wp'.
7068  */
7069     void
7070 clear_matches(win_T *wp)
7071 {
7072     matchitem_T *m;
7073 
7074     while (wp->w_match_head != NULL)
7075     {
7076 	m = wp->w_match_head->next;
7077 	vim_regfree(wp->w_match_head->match.regprog);
7078 	vim_free(wp->w_match_head->pattern);
7079 	vim_free(wp->w_match_head);
7080 	wp->w_match_head = m;
7081     }
7082     redraw_later(SOME_VALID);
7083 }
7084 
7085 /*
7086  * Get match from ID 'id' in window 'wp'.
7087  * Return NULL if match not found.
7088  */
7089     matchitem_T *
7090 get_match(win_T *wp, int id)
7091 {
7092     matchitem_T *cur = wp->w_match_head;
7093 
7094     while (cur != NULL && cur->id != id)
7095 	cur = cur->next;
7096     return cur;
7097 }
7098 #endif
7099 
7100 #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) || defined(PROTO)
7101     int
7102 get_win_number(win_T *wp, win_T *first_win)
7103 {
7104     int		i = 1;
7105     win_T	*w;
7106 
7107     for (w = first_win; w != NULL && w != wp; w = W_NEXT(w))
7108 	++i;
7109 
7110     if (w == NULL)
7111 	return 0;
7112     else
7113 	return i;
7114 }
7115 
7116     int
7117 get_tab_number(tabpage_T *tp UNUSED)
7118 {
7119     int		i = 1;
7120 # ifdef FEAT_WINDOWS
7121     tabpage_T	*t;
7122 
7123     for (t = first_tabpage; t != NULL && t != tp; t = t->tp_next)
7124 	++i;
7125 
7126     if (t == NULL)
7127 	return 0;
7128     else
7129 # endif
7130 	return i;
7131 }
7132 #endif
7133 
7134 #if defined(FEAT_WINDOWS) || defined(PROTO)
7135 /*
7136  * Return TRUE if "topfrp" and its children are at the right height.
7137  */
7138     static int
7139 frame_check_height(frame_T *topfrp, int height)
7140 {
7141     frame_T *frp;
7142 
7143     if (topfrp->fr_height != height)
7144 	return FALSE;
7145 
7146     if (topfrp->fr_layout == FR_ROW)
7147 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
7148 	    if (frp->fr_height != height)
7149 		return FALSE;
7150 
7151     return TRUE;
7152 }
7153 #endif
7154 
7155 #if defined(FEAT_WINDOWS) || defined(PROTO)
7156 /*
7157  * Return TRUE if "topfrp" and its children are at the right width.
7158  */
7159     static int
7160 frame_check_width(frame_T *topfrp, int width)
7161 {
7162     frame_T *frp;
7163 
7164     if (topfrp->fr_width != width)
7165 	return FALSE;
7166 
7167     if (topfrp->fr_layout == FR_COL)
7168 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
7169 	    if (frp->fr_width != width)
7170 		return FALSE;
7171 
7172     return TRUE;
7173 }
7174 #endif
7175 
7176 #if defined(FEAT_EVAL) || defined(PROTO)
7177     int
7178 win_getid(typval_T *argvars)
7179 {
7180     int	    winnr;
7181     win_T   *wp;
7182 
7183     if (argvars[0].v_type == VAR_UNKNOWN)
7184 	return curwin->w_id;
7185     winnr = get_tv_number(&argvars[0]);
7186     if (winnr > 0)
7187     {
7188 	if (argvars[1].v_type == VAR_UNKNOWN)
7189 	    wp = firstwin;
7190 	else
7191 	{
7192 	    tabpage_T	*tp;
7193 	    int		tabnr = get_tv_number(&argvars[1]);
7194 
7195 	    FOR_ALL_TABPAGES(tp)
7196 		if (--tabnr == 0)
7197 		    break;
7198 	    if (tp == NULL)
7199 		return -1;
7200 	    if (tp == curtab)
7201 		wp = firstwin;
7202 	    else
7203 		wp = tp->tp_firstwin;
7204 	}
7205 	for ( ; wp != NULL; wp = wp->w_next)
7206 	    if (--winnr == 0)
7207 		return wp->w_id;
7208     }
7209     return 0;
7210 }
7211 
7212     int
7213 win_gotoid(typval_T *argvars)
7214 {
7215     win_T	*wp;
7216     tabpage_T   *tp;
7217     int		id = get_tv_number(&argvars[0]);
7218 
7219     FOR_ALL_TAB_WINDOWS(tp, wp)
7220 	    if (wp->w_id == id)
7221 	    {
7222 		goto_tabpage_win(tp, wp);
7223 		return 1;
7224 	    }
7225     return 0;
7226 }
7227 
7228     void
7229 win_id2tabwin(typval_T *argvars, list_T *list)
7230 {
7231     win_T	*wp;
7232     tabpage_T   *tp;
7233     int		winnr = 1;
7234     int		tabnr = 1;
7235     int		id = get_tv_number(&argvars[0]);
7236 
7237     FOR_ALL_TABPAGES(tp)
7238     {
7239 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
7240 	{
7241 	    if (wp->w_id == id)
7242 	    {
7243 		list_append_number(list, tabnr);
7244 		list_append_number(list, winnr);
7245 		return;
7246 	    }
7247 	    ++winnr;
7248 	}
7249 	++tabnr;
7250 	winnr = 1;
7251     }
7252     list_append_number(list, 0);
7253     list_append_number(list, 0);
7254 }
7255 
7256     win_T *
7257 win_id2wp(typval_T *argvars)
7258 {
7259     win_T	*wp;
7260     tabpage_T   *tp;
7261     int		id = get_tv_number(&argvars[0]);
7262 
7263     FOR_ALL_TAB_WINDOWS(tp, wp)
7264 	if (wp->w_id == id)
7265 	    return wp;
7266 
7267     return NULL;
7268 }
7269 
7270     int
7271 win_id2win(typval_T *argvars)
7272 {
7273     win_T   *wp;
7274     int	    nr = 1;
7275     int	    id = get_tv_number(&argvars[0]);
7276 
7277     FOR_ALL_WINDOWS(wp)
7278     {
7279 	if (wp->w_id == id)
7280 	    return nr;
7281 	++nr;
7282     }
7283     return 0;
7284 }
7285 
7286     void
7287 win_findbuf(typval_T *argvars, list_T *list)
7288 {
7289     win_T	*wp;
7290     tabpage_T   *tp;
7291     int		bufnr = get_tv_number(&argvars[0]);
7292 
7293     FOR_ALL_TAB_WINDOWS(tp, wp)
7294 	    if (wp->w_buffer->b_fnum == bufnr)
7295 		list_append_number(list, wp->w_id);
7296 }
7297 
7298 #endif
7299