xref: /vim-8.2.3635/src/window.c (revision e16b00a1)
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     frame_T	*win_frame = win->w_frame->fr_parent;
2286 
2287     if (last_window())
2288     {
2289 	EMSG(_("E444: Cannot close last window"));
2290 	return FAIL;
2291     }
2292 
2293 #ifdef FEAT_AUTOCMD
2294     if (win->w_closing || (win->w_buffer != NULL
2295 					       && win->w_buffer->b_locked > 0))
2296 	return FAIL; /* window is already being closed */
2297     if (win == aucmd_win)
2298     {
2299 	EMSG(_("E813: Cannot close autocmd window"));
2300 	return FAIL;
2301     }
2302     if ((firstwin == aucmd_win || lastwin == aucmd_win) && one_window())
2303     {
2304 	EMSG(_("E814: Cannot close window, only autocmd window would remain"));
2305 	return FAIL;
2306     }
2307 #endif
2308 
2309     /* When closing the last window in a tab page first go to another tab page
2310      * and then close the window and the tab page to avoid that curwin and
2311      * curtab are invalid while we are freeing memory. */
2312     if (close_last_window_tabpage(win, free_buf, prev_curtab))
2313       return FAIL;
2314 
2315     /* When closing the help window, try restoring a snapshot after closing
2316      * the window.  Otherwise clear the snapshot, it's now invalid. */
2317     if (bt_help(win->w_buffer))
2318 	help_window = TRUE;
2319     else
2320 	clear_snapshot(curtab, SNAP_HELP_IDX);
2321 
2322 #ifdef FEAT_AUTOCMD
2323     if (win == curwin)
2324     {
2325 	/*
2326 	 * Guess which window is going to be the new current window.
2327 	 * This may change because of the autocommands (sigh).
2328 	 */
2329 	wp = frame2win(win_altframe(win, NULL));
2330 
2331 	/*
2332 	 * Be careful: If autocommands delete the window or cause this window
2333 	 * to be the last one left, return now.
2334 	 */
2335 	if (wp->w_buffer != curbuf)
2336 	{
2337 	    other_buffer = TRUE;
2338 	    win->w_closing = TRUE;
2339 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
2340 	    if (!win_valid(win))
2341 		return FAIL;
2342 	    win->w_closing = FALSE;
2343 	    if (last_window())
2344 		return FAIL;
2345 	}
2346 	win->w_closing = TRUE;
2347 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
2348 	if (!win_valid(win))
2349 	    return FAIL;
2350 	win->w_closing = FALSE;
2351 	if (last_window())
2352 	    return FAIL;
2353 # ifdef FEAT_EVAL
2354 	/* autocmds may abort script processing */
2355 	if (aborting())
2356 	    return FAIL;
2357 # endif
2358     }
2359 #endif
2360 
2361 #ifdef FEAT_GUI
2362     /* Avoid trouble with scrollbars that are going to be deleted in
2363      * win_free(). */
2364     if (gui.in_use)
2365 	out_flush();
2366 #endif
2367 
2368 #ifdef FEAT_SYN_HL
2369     /* Free independent synblock before the buffer is freed. */
2370     if (win->w_buffer != NULL)
2371 	reset_synblock(win);
2372 #endif
2373 
2374     /*
2375      * Close the link to the buffer.
2376      */
2377     if (win->w_buffer != NULL)
2378     {
2379 	bufref_T    bufref;
2380 
2381 	set_bufref(&bufref, curbuf);
2382 #ifdef FEAT_AUTOCMD
2383 	win->w_closing = TRUE;
2384 #endif
2385 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0, TRUE);
2386 #ifdef FEAT_AUTOCMD
2387 	if (win_valid_any_tab(win))
2388 	    win->w_closing = FALSE;
2389 #endif
2390 	/* Make sure curbuf is valid. It can become invalid if 'bufhidden' is
2391 	 * "wipe". */
2392 	if (!bufref_valid(&bufref))
2393 	    curbuf = firstbuf;
2394     }
2395 
2396     if (only_one_window() && win_valid(win) && win->w_buffer == NULL
2397 	    && (last_window() || curtab != prev_curtab
2398 		|| close_last_window_tabpage(win, free_buf, prev_curtab)))
2399     {
2400 	/* Autocommands have closed all windows, quit now.  Restore
2401 	 * curwin->w_buffer, otherwise writing viminfo may fail. */
2402 	if (curwin->w_buffer == NULL)
2403 	    curwin->w_buffer = curbuf;
2404 	getout(0);
2405     }
2406 
2407     /* Autocommands may have moved to another tab page. */
2408     if (curtab != prev_curtab && win_valid_any_tab(win)
2409 						      && win->w_buffer == NULL)
2410     {
2411 	/* Need to close the window anyway, since the buffer is NULL. */
2412 	win_close_othertab(win, FALSE, prev_curtab);
2413 	return FAIL;
2414     }
2415 
2416     /* Autocommands may have closed the window already or closed the only
2417      * other window. */
2418     if (!win_valid(win) || last_window()
2419 	    || close_last_window_tabpage(win, free_buf, prev_curtab))
2420 	return FAIL;
2421 
2422     /* Free the memory used for the window and get the window that received
2423      * the screen space. */
2424     wp = win_free_mem(win, &dir, NULL);
2425 
2426     /* Make sure curwin isn't invalid.  It can cause severe trouble when
2427      * printing an error message.  For win_equal() curbuf needs to be valid
2428      * too. */
2429     if (win == curwin)
2430     {
2431 	curwin = wp;
2432 #ifdef FEAT_QUICKFIX
2433 	if (wp->w_p_pvw || bt_quickfix(wp->w_buffer))
2434 	{
2435 	    /*
2436 	     * If the cursor goes to the preview or the quickfix window, try
2437 	     * finding another window to go to.
2438 	     */
2439 	    for (;;)
2440 	    {
2441 		if (wp->w_next == NULL)
2442 		    wp = firstwin;
2443 		else
2444 		    wp = wp->w_next;
2445 		if (wp == curwin)
2446 		    break;
2447 		if (!wp->w_p_pvw && !bt_quickfix(wp->w_buffer))
2448 		{
2449 		    curwin = wp;
2450 		    break;
2451 		}
2452 	    }
2453 	}
2454 #endif
2455 	curbuf = curwin->w_buffer;
2456 	close_curwin = TRUE;
2457 
2458 	/* The cursor position may be invalid if the buffer changed after last
2459 	 * using the window. */
2460 	check_cursor();
2461     }
2462     if (p_ea && (*p_ead == 'b' || *p_ead == dir))
2463 	/* If the frame of the closed window contains the new current window,
2464 	 * only resize that frame.  Otherwise resize all windows. */
2465 	win_equal(curwin, curwin->w_frame->fr_parent == win_frame, dir);
2466     else
2467 	win_comp_pos();
2468     if (close_curwin)
2469     {
2470 	win_enter_ext(wp, FALSE, TRUE, FALSE, TRUE, TRUE);
2471 #ifdef FEAT_AUTOCMD
2472 	if (other_buffer)
2473 	    /* careful: after this wp and win may be invalid! */
2474 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
2475 #endif
2476     }
2477 
2478     /*
2479      * If last window has a status line now and we don't want one,
2480      * remove the status line.
2481      */
2482     last_status(FALSE);
2483 
2484     /* After closing the help window, try restoring the window layout from
2485      * before it was opened. */
2486     if (help_window)
2487 	restore_snapshot(SNAP_HELP_IDX, close_curwin);
2488 
2489 #if defined(FEAT_GUI)
2490     /* When 'guioptions' includes 'L' or 'R' may have to remove scrollbars. */
2491     if (gui.in_use && !win_hasvertsplit())
2492 	gui_init_which_components(NULL);
2493 #endif
2494 
2495     redraw_all_later(NOT_VALID);
2496     return OK;
2497 }
2498 
2499 /*
2500  * Close window "win" in tab page "tp", which is not the current tab page.
2501  * This may be the last window in that tab page and result in closing the tab,
2502  * thus "tp" may become invalid!
2503  * Caller must check if buffer is hidden and whether the tabline needs to be
2504  * updated.
2505  */
2506     void
2507 win_close_othertab(win_T *win, int free_buf, tabpage_T *tp)
2508 {
2509     win_T	*wp;
2510     int		dir;
2511     tabpage_T   *ptp = NULL;
2512     int		free_tp = FALSE;
2513 
2514 #ifdef FEAT_AUTOCMD
2515     /* Get here with win->w_buffer == NULL when win_close() detects the tab
2516      * page changed. */
2517     if (win->w_closing || (win->w_buffer != NULL
2518 					       && win->w_buffer->b_locked > 0))
2519 	return; /* window is already being closed */
2520 #endif
2521 
2522     if (win->w_buffer != NULL)
2523 	/* Close the link to the buffer. */
2524 	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0, FALSE);
2525 
2526     /* Careful: Autocommands may have closed the tab page or made it the
2527      * current tab page.  */
2528     for (ptp = first_tabpage; ptp != NULL && ptp != tp; ptp = ptp->tp_next)
2529 	;
2530     if (ptp == NULL || tp == curtab)
2531 	return;
2532 
2533     /* Autocommands may have closed the window already. */
2534     for (wp = tp->tp_firstwin; wp != NULL && wp != win; wp = wp->w_next)
2535 	;
2536     if (wp == NULL)
2537 	return;
2538 
2539     /* When closing the last window in a tab page remove the tab page. */
2540     if (tp->tp_firstwin == tp->tp_lastwin)
2541     {
2542 	if (tp == first_tabpage)
2543 	    first_tabpage = tp->tp_next;
2544 	else
2545 	{
2546 	    for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tp;
2547 							   ptp = ptp->tp_next)
2548 		;
2549 	    if (ptp == NULL)
2550 	    {
2551 		internal_error("win_close_othertab()");
2552 		return;
2553 	    }
2554 	    ptp->tp_next = tp->tp_next;
2555 	}
2556 	free_tp = TRUE;
2557     }
2558 
2559     /* Free the memory used for the window. */
2560     win_free_mem(win, &dir, tp);
2561 
2562     if (free_tp)
2563 	free_tabpage(tp);
2564 }
2565 
2566 /*
2567  * Free the memory used for a window.
2568  * Returns a pointer to the window that got the freed up space.
2569  */
2570     static win_T *
2571 win_free_mem(
2572     win_T	*win,
2573     int		*dirp,		/* set to 'v' or 'h' for direction if 'ea' */
2574     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2575 {
2576     frame_T	*frp;
2577     win_T	*wp;
2578 
2579     /* Remove the window and its frame from the tree of frames. */
2580     frp = win->w_frame;
2581     wp = winframe_remove(win, dirp, tp);
2582     vim_free(frp);
2583     win_free(win, tp);
2584 
2585     /* When deleting the current window of another tab page select a new
2586      * current window. */
2587     if (tp != NULL && win == tp->tp_curwin)
2588 	tp->tp_curwin = wp;
2589 
2590     return wp;
2591 }
2592 
2593 #if defined(EXITFREE) || defined(PROTO)
2594     void
2595 win_free_all(void)
2596 {
2597     int		dummy;
2598 
2599 # ifdef FEAT_WINDOWS
2600     while (first_tabpage->tp_next != NULL)
2601 	tabpage_close(TRUE);
2602 # endif
2603 
2604 # ifdef FEAT_AUTOCMD
2605     if (aucmd_win != NULL)
2606     {
2607 	(void)win_free_mem(aucmd_win, &dummy, NULL);
2608 	aucmd_win = NULL;
2609     }
2610 # endif
2611 
2612     while (firstwin != NULL)
2613 	(void)win_free_mem(firstwin, &dummy, NULL);
2614 
2615     /* No window should be used after this. Set curwin to NULL to crash
2616      * instead of using freed memory. */
2617     curwin = NULL;
2618 }
2619 #endif
2620 
2621 /*
2622  * Remove a window and its frame from the tree of frames.
2623  * Returns a pointer to the window that got the freed up space.
2624  */
2625     win_T *
2626 winframe_remove(
2627     win_T	*win,
2628     int		*dirp UNUSED,	/* set to 'v' or 'h' for direction if 'ea' */
2629     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2630 {
2631     frame_T	*frp, *frp2, *frp3;
2632     frame_T	*frp_close = win->w_frame;
2633     win_T	*wp;
2634 
2635     /*
2636      * If there is only one window there is nothing to remove.
2637      */
2638     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2639 	return NULL;
2640 
2641     /*
2642      * Remove the window from its frame.
2643      */
2644     frp2 = win_altframe(win, tp);
2645     wp = frame2win(frp2);
2646 
2647     /* Remove this frame from the list of frames. */
2648     frame_remove(frp_close);
2649 
2650     if (frp_close->fr_parent->fr_layout == FR_COL)
2651     {
2652 	/* When 'winfixheight' is set, try to find another frame in the column
2653 	 * (as close to the closed frame as possible) to distribute the height
2654 	 * to. */
2655 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfh)
2656 	{
2657 	    frp = frp_close->fr_prev;
2658 	    frp3 = frp_close->fr_next;
2659 	    while (frp != NULL || frp3 != NULL)
2660 	    {
2661 		if (frp != NULL)
2662 		{
2663 		    if (frp->fr_win != NULL && !frp->fr_win->w_p_wfh)
2664 		    {
2665 			frp2 = frp;
2666 			wp = frp->fr_win;
2667 			break;
2668 		    }
2669 		    frp = frp->fr_prev;
2670 		}
2671 		if (frp3 != NULL)
2672 		{
2673 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfh)
2674 		    {
2675 			frp2 = frp3;
2676 			wp = frp3->fr_win;
2677 			break;
2678 		    }
2679 		    frp3 = frp3->fr_next;
2680 		}
2681 	    }
2682 	}
2683 	frame_new_height(frp2, frp2->fr_height + frp_close->fr_height,
2684 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2685 	*dirp = 'v';
2686     }
2687     else
2688     {
2689 	/* When 'winfixwidth' is set, try to find another frame in the column
2690 	 * (as close to the closed frame as possible) to distribute the width
2691 	 * to. */
2692 	if (frp2->fr_win != NULL && frp2->fr_win->w_p_wfw)
2693 	{
2694 	    frp = frp_close->fr_prev;
2695 	    frp3 = frp_close->fr_next;
2696 	    while (frp != NULL || frp3 != NULL)
2697 	    {
2698 		if (frp != NULL)
2699 		{
2700 		    if (frp->fr_win != NULL && !frp->fr_win->w_p_wfw)
2701 		    {
2702 			frp2 = frp;
2703 			wp = frp->fr_win;
2704 			break;
2705 		    }
2706 		    frp = frp->fr_prev;
2707 		}
2708 		if (frp3 != NULL)
2709 		{
2710 		    if (frp3->fr_win != NULL && !frp3->fr_win->w_p_wfw)
2711 		    {
2712 			frp2 = frp3;
2713 			wp = frp3->fr_win;
2714 			break;
2715 		    }
2716 		    frp3 = frp3->fr_next;
2717 		}
2718 	    }
2719 	}
2720 	frame_new_width(frp2, frp2->fr_width + frp_close->fr_width,
2721 			    frp2 == frp_close->fr_next ? TRUE : FALSE, FALSE);
2722 	*dirp = 'h';
2723     }
2724 
2725     /* If rows/columns go to a window below/right its positions need to be
2726      * updated.  Can only be done after the sizes have been updated. */
2727     if (frp2 == frp_close->fr_next)
2728     {
2729 	int row = win->w_winrow;
2730 	int col = W_WINCOL(win);
2731 
2732 	frame_comp_pos(frp2, &row, &col);
2733     }
2734 
2735     if (frp2->fr_next == NULL && frp2->fr_prev == NULL)
2736     {
2737 	/* There is no other frame in this list, move its info to the parent
2738 	 * and remove it. */
2739 	frp2->fr_parent->fr_layout = frp2->fr_layout;
2740 	frp2->fr_parent->fr_child = frp2->fr_child;
2741 	for (frp = frp2->fr_child; frp != NULL; frp = frp->fr_next)
2742 	    frp->fr_parent = frp2->fr_parent;
2743 	frp2->fr_parent->fr_win = frp2->fr_win;
2744 	if (frp2->fr_win != NULL)
2745 	    frp2->fr_win->w_frame = frp2->fr_parent;
2746 	frp = frp2->fr_parent;
2747 	vim_free(frp2);
2748 
2749 	frp2 = frp->fr_parent;
2750 	if (frp2 != NULL && frp2->fr_layout == frp->fr_layout)
2751 	{
2752 	    /* The frame above the parent has the same layout, have to merge
2753 	     * the frames into this list. */
2754 	    if (frp2->fr_child == frp)
2755 		frp2->fr_child = frp->fr_child;
2756 	    frp->fr_child->fr_prev = frp->fr_prev;
2757 	    if (frp->fr_prev != NULL)
2758 		frp->fr_prev->fr_next = frp->fr_child;
2759 	    for (frp3 = frp->fr_child; ; frp3 = frp3->fr_next)
2760 	    {
2761 		frp3->fr_parent = frp2;
2762 		if (frp3->fr_next == NULL)
2763 		{
2764 		    frp3->fr_next = frp->fr_next;
2765 		    if (frp->fr_next != NULL)
2766 			frp->fr_next->fr_prev = frp3;
2767 		    break;
2768 		}
2769 	    }
2770 	    vim_free(frp);
2771 	}
2772     }
2773 
2774     return wp;
2775 }
2776 
2777 /*
2778  * Find out which frame is going to get the freed up space when "win" is
2779  * closed.
2780  * if 'splitbelow'/'splitleft' the space goes to the window above/left.
2781  * if 'nosplitbelow'/'nosplitleft' the space goes to the window below/right.
2782  * This makes opening a window and closing it immediately keep the same window
2783  * layout.
2784  */
2785     static frame_T *
2786 win_altframe(
2787     win_T	*win,
2788     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
2789 {
2790     frame_T	*frp;
2791     int		b;
2792 
2793     if (tp == NULL ? ONE_WINDOW : tp->tp_firstwin == tp->tp_lastwin)
2794 	/* Last window in this tab page, will go to next tab page. */
2795 	return alt_tabpage()->tp_curwin->w_frame;
2796 
2797     frp = win->w_frame;
2798     if (frp->fr_parent != NULL && frp->fr_parent->fr_layout == FR_ROW)
2799 	b = p_spr;
2800     else
2801 	b = p_sb;
2802     if ((!b && frp->fr_next != NULL) || frp->fr_prev == NULL)
2803 	return frp->fr_next;
2804     return frp->fr_prev;
2805 }
2806 
2807 /*
2808  * Return the tabpage that will be used if the current one is closed.
2809  */
2810     static tabpage_T *
2811 alt_tabpage(void)
2812 {
2813     tabpage_T	*tp;
2814 
2815     /* Use the next tab page if possible. */
2816     if (curtab->tp_next != NULL)
2817 	return curtab->tp_next;
2818 
2819     /* Find the last but one tab page. */
2820     for (tp = first_tabpage; tp->tp_next != curtab; tp = tp->tp_next)
2821 	;
2822     return tp;
2823 }
2824 
2825 /*
2826  * Find the left-upper window in frame "frp".
2827  */
2828     static win_T *
2829 frame2win(frame_T *frp)
2830 {
2831     while (frp->fr_win == NULL)
2832 	frp = frp->fr_child;
2833     return frp->fr_win;
2834 }
2835 
2836 /*
2837  * Return TRUE if frame "frp" contains window "wp".
2838  */
2839     static int
2840 frame_has_win(frame_T *frp, win_T *wp)
2841 {
2842     frame_T	*p;
2843 
2844     if (frp->fr_layout == FR_LEAF)
2845 	return frp->fr_win == wp;
2846 
2847     for (p = frp->fr_child; p != NULL; p = p->fr_next)
2848 	if (frame_has_win(p, wp))
2849 	    return TRUE;
2850     return FALSE;
2851 }
2852 
2853 /*
2854  * Set a new height for a frame.  Recursively sets the height for contained
2855  * frames and windows.  Caller must take care of positions.
2856  */
2857     static void
2858 frame_new_height(
2859     frame_T	*topfrp,
2860     int		height,
2861     int		topfirst,	/* resize topmost contained frame first */
2862     int		wfh)		/* obey 'winfixheight' when there is a choice;
2863 				   may cause the height not to be set */
2864 {
2865     frame_T	*frp;
2866     int		extra_lines;
2867     int		h;
2868 
2869     if (topfrp->fr_win != NULL)
2870     {
2871 	/* Simple case: just one window. */
2872 	win_new_height(topfrp->fr_win,
2873 				    height - topfrp->fr_win->w_status_height);
2874     }
2875     else if (topfrp->fr_layout == FR_ROW)
2876     {
2877 	do
2878 	{
2879 	    /* All frames in this row get the same new height. */
2880 	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
2881 	    {
2882 		frame_new_height(frp, height, topfirst, wfh);
2883 		if (frp->fr_height > height)
2884 		{
2885 		    /* Could not fit the windows, make the whole row higher. */
2886 		    height = frp->fr_height;
2887 		    break;
2888 		}
2889 	    }
2890 	}
2891 	while (frp != NULL);
2892     }
2893     else    /* fr_layout == FR_COL */
2894     {
2895 	/* Complicated case: Resize a column of frames.  Resize the bottom
2896 	 * frame first, frames above that when needed. */
2897 
2898 	frp = topfrp->fr_child;
2899 	if (wfh)
2900 	    /* Advance past frames with one window with 'wfh' set. */
2901 	    while (frame_fixed_height(frp))
2902 	    {
2903 		frp = frp->fr_next;
2904 		if (frp == NULL)
2905 		    return;	    /* no frame without 'wfh', give up */
2906 	    }
2907 	if (!topfirst)
2908 	{
2909 	    /* Find the bottom frame of this column */
2910 	    while (frp->fr_next != NULL)
2911 		frp = frp->fr_next;
2912 	    if (wfh)
2913 		/* Advance back for frames with one window with 'wfh' set. */
2914 		while (frame_fixed_height(frp))
2915 		    frp = frp->fr_prev;
2916 	}
2917 
2918 	extra_lines = height - topfrp->fr_height;
2919 	if (extra_lines < 0)
2920 	{
2921 	    /* reduce height of contained frames, bottom or top frame first */
2922 	    while (frp != NULL)
2923 	    {
2924 		h = frame_minheight(frp, NULL);
2925 		if (frp->fr_height + extra_lines < h)
2926 		{
2927 		    extra_lines += frp->fr_height - h;
2928 		    frame_new_height(frp, h, topfirst, wfh);
2929 		}
2930 		else
2931 		{
2932 		    frame_new_height(frp, frp->fr_height + extra_lines,
2933 							       topfirst, wfh);
2934 		    break;
2935 		}
2936 		if (topfirst)
2937 		{
2938 		    do
2939 			frp = frp->fr_next;
2940 		    while (wfh && frp != NULL && frame_fixed_height(frp));
2941 		}
2942 		else
2943 		{
2944 		    do
2945 			frp = frp->fr_prev;
2946 		    while (wfh && frp != NULL && frame_fixed_height(frp));
2947 		}
2948 		/* Increase "height" if we could not reduce enough frames. */
2949 		if (frp == NULL)
2950 		    height -= extra_lines;
2951 	    }
2952 	}
2953 	else if (extra_lines > 0)
2954 	{
2955 	    /* increase height of bottom or top frame */
2956 	    frame_new_height(frp, frp->fr_height + extra_lines, topfirst, wfh);
2957 	}
2958     }
2959     topfrp->fr_height = height;
2960 }
2961 
2962 /*
2963  * Return TRUE if height of frame "frp" should not be changed because of
2964  * the 'winfixheight' option.
2965  */
2966     static int
2967 frame_fixed_height(frame_T *frp)
2968 {
2969     /* frame with one window: fixed height if 'winfixheight' set. */
2970     if (frp->fr_win != NULL)
2971 	return frp->fr_win->w_p_wfh;
2972 
2973     if (frp->fr_layout == FR_ROW)
2974     {
2975 	/* The frame is fixed height if one of the frames in the row is fixed
2976 	 * height. */
2977 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
2978 	    if (frame_fixed_height(frp))
2979 		return TRUE;
2980 	return FALSE;
2981     }
2982 
2983     /* frp->fr_layout == FR_COL: The frame is fixed height if all of the
2984      * frames in the row are fixed height. */
2985     for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
2986 	if (!frame_fixed_height(frp))
2987 	    return FALSE;
2988     return TRUE;
2989 }
2990 
2991 /*
2992  * Return TRUE if width of frame "frp" should not be changed because of
2993  * the 'winfixwidth' option.
2994  */
2995     static int
2996 frame_fixed_width(frame_T *frp)
2997 {
2998     /* frame with one window: fixed width if 'winfixwidth' set. */
2999     if (frp->fr_win != NULL)
3000 	return frp->fr_win->w_p_wfw;
3001 
3002     if (frp->fr_layout == FR_COL)
3003     {
3004 	/* The frame is fixed width if one of the frames in the row is fixed
3005 	 * width. */
3006 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3007 	    if (frame_fixed_width(frp))
3008 		return TRUE;
3009 	return FALSE;
3010     }
3011 
3012     /* frp->fr_layout == FR_ROW: The frame is fixed width if all of the
3013      * frames in the row are fixed width. */
3014     for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3015 	if (!frame_fixed_width(frp))
3016 	    return FALSE;
3017     return TRUE;
3018 }
3019 
3020 /*
3021  * Add a status line to windows at the bottom of "frp".
3022  * Note: Does not check if there is room!
3023  */
3024     static void
3025 frame_add_statusline(frame_T *frp)
3026 {
3027     win_T	*wp;
3028 
3029     if (frp->fr_layout == FR_LEAF)
3030     {
3031 	wp = frp->fr_win;
3032 	if (wp->w_status_height == 0)
3033 	{
3034 	    if (wp->w_height > 0)	/* don't make it negative */
3035 		--wp->w_height;
3036 	    wp->w_status_height = STATUS_HEIGHT;
3037 	}
3038     }
3039     else if (frp->fr_layout == FR_ROW)
3040     {
3041 	/* Handle all the frames in the row. */
3042 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3043 	    frame_add_statusline(frp);
3044     }
3045     else /* frp->fr_layout == FR_COL */
3046     {
3047 	/* Only need to handle the last frame in the column. */
3048 	for (frp = frp->fr_child; frp->fr_next != NULL; frp = frp->fr_next)
3049 	    ;
3050 	frame_add_statusline(frp);
3051     }
3052 }
3053 
3054 /*
3055  * Set width of a frame.  Handles recursively going through contained frames.
3056  * May remove separator line for windows at the right side (for win_close()).
3057  */
3058     static void
3059 frame_new_width(
3060     frame_T	*topfrp,
3061     int		width,
3062     int		leftfirst,	/* resize leftmost contained frame first */
3063     int		wfw)		/* obey 'winfixwidth' when there is a choice;
3064 				   may cause the width not to be set */
3065 {
3066     frame_T	*frp;
3067     int		extra_cols;
3068     int		w;
3069     win_T	*wp;
3070 
3071     if (topfrp->fr_layout == FR_LEAF)
3072     {
3073 	/* Simple case: just one window. */
3074 	wp = topfrp->fr_win;
3075 	/* Find out if there are any windows right of this one. */
3076 	for (frp = topfrp; frp->fr_parent != NULL; frp = frp->fr_parent)
3077 	    if (frp->fr_parent->fr_layout == FR_ROW && frp->fr_next != NULL)
3078 		break;
3079 	if (frp->fr_parent == NULL)
3080 	    wp->w_vsep_width = 0;
3081 	win_new_width(wp, width - wp->w_vsep_width);
3082     }
3083     else if (topfrp->fr_layout == FR_COL)
3084     {
3085 	do
3086 	{
3087 	    /* All frames in this column get the same new width. */
3088 	    for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3089 	    {
3090 		frame_new_width(frp, width, leftfirst, wfw);
3091 		if (frp->fr_width > width)
3092 		{
3093 		    /* Could not fit the windows, make whole column wider. */
3094 		    width = frp->fr_width;
3095 		    break;
3096 		}
3097 	    }
3098 	} while (frp != NULL);
3099     }
3100     else    /* fr_layout == FR_ROW */
3101     {
3102 	/* Complicated case: Resize a row of frames.  Resize the rightmost
3103 	 * frame first, frames left of it when needed. */
3104 
3105 	frp = topfrp->fr_child;
3106 	if (wfw)
3107 	    /* Advance past frames with one window with 'wfw' set. */
3108 	    while (frame_fixed_width(frp))
3109 	    {
3110 		frp = frp->fr_next;
3111 		if (frp == NULL)
3112 		    return;	    /* no frame without 'wfw', give up */
3113 	    }
3114 	if (!leftfirst)
3115 	{
3116 	    /* Find the rightmost frame of this row */
3117 	    while (frp->fr_next != NULL)
3118 		frp = frp->fr_next;
3119 	    if (wfw)
3120 		/* Advance back for frames with one window with 'wfw' set. */
3121 		while (frame_fixed_width(frp))
3122 		    frp = frp->fr_prev;
3123 	}
3124 
3125 	extra_cols = width - topfrp->fr_width;
3126 	if (extra_cols < 0)
3127 	{
3128 	    /* reduce frame width, rightmost frame first */
3129 	    while (frp != NULL)
3130 	    {
3131 		w = frame_minwidth(frp, NULL);
3132 		if (frp->fr_width + extra_cols < w)
3133 		{
3134 		    extra_cols += frp->fr_width - w;
3135 		    frame_new_width(frp, w, leftfirst, wfw);
3136 		}
3137 		else
3138 		{
3139 		    frame_new_width(frp, frp->fr_width + extra_cols,
3140 							      leftfirst, wfw);
3141 		    break;
3142 		}
3143 		if (leftfirst)
3144 		{
3145 		    do
3146 			frp = frp->fr_next;
3147 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3148 		}
3149 		else
3150 		{
3151 		    do
3152 			frp = frp->fr_prev;
3153 		    while (wfw && frp != NULL && frame_fixed_width(frp));
3154 		}
3155 		/* Increase "width" if we could not reduce enough frames. */
3156 		if (frp == NULL)
3157 		    width -= extra_cols;
3158 	    }
3159 	}
3160 	else if (extra_cols > 0)
3161 	{
3162 	    /* increase width of rightmost frame */
3163 	    frame_new_width(frp, frp->fr_width + extra_cols, leftfirst, wfw);
3164 	}
3165     }
3166     topfrp->fr_width = width;
3167 }
3168 
3169 /*
3170  * Add the vertical separator to windows at the right side of "frp".
3171  * Note: Does not check if there is room!
3172  */
3173     static void
3174 frame_add_vsep(frame_T *frp)
3175 {
3176     win_T	*wp;
3177 
3178     if (frp->fr_layout == FR_LEAF)
3179     {
3180 	wp = frp->fr_win;
3181 	if (wp->w_vsep_width == 0)
3182 	{
3183 	    if (wp->w_width > 0)	/* don't make it negative */
3184 		--wp->w_width;
3185 	    wp->w_vsep_width = 1;
3186 	}
3187     }
3188     else if (frp->fr_layout == FR_COL)
3189     {
3190 	/* Handle all the frames in the column. */
3191 	for (frp = frp->fr_child; frp != NULL; frp = frp->fr_next)
3192 	    frame_add_vsep(frp);
3193     }
3194     else /* frp->fr_layout == FR_ROW */
3195     {
3196 	/* Only need to handle the last frame in the row. */
3197 	frp = frp->fr_child;
3198 	while (frp->fr_next != NULL)
3199 	    frp = frp->fr_next;
3200 	frame_add_vsep(frp);
3201     }
3202 }
3203 
3204 /*
3205  * Set frame width from the window it contains.
3206  */
3207     static void
3208 frame_fix_width(win_T *wp)
3209 {
3210     wp->w_frame->fr_width = wp->w_width + wp->w_vsep_width;
3211 }
3212 
3213 /*
3214  * Set frame height from the window it contains.
3215  */
3216     static void
3217 frame_fix_height(win_T *wp)
3218 {
3219     wp->w_frame->fr_height = wp->w_height + wp->w_status_height;
3220 }
3221 
3222 /*
3223  * Compute the minimal height for frame "topfrp".
3224  * Uses the 'winminheight' option.
3225  * When "next_curwin" isn't NULL, use p_wh for this window.
3226  * When "next_curwin" is NOWIN, don't use at least one line for the current
3227  * window.
3228  */
3229     static int
3230 frame_minheight(frame_T *topfrp, win_T *next_curwin)
3231 {
3232     frame_T	*frp;
3233     int		m;
3234     int		n;
3235 
3236     if (topfrp->fr_win != NULL)
3237     {
3238 	if (topfrp->fr_win == next_curwin)
3239 	    m = p_wh + topfrp->fr_win->w_status_height;
3240 	else
3241 	{
3242 	    /* window: minimal height of the window plus status line */
3243 	    m = p_wmh + topfrp->fr_win->w_status_height;
3244 	    /* Current window is minimal one line high */
3245 	    if (p_wmh == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3246 		++m;
3247 	}
3248     }
3249     else if (topfrp->fr_layout == FR_ROW)
3250     {
3251 	/* get the minimal height from each frame in this row */
3252 	m = 0;
3253 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3254 	{
3255 	    n = frame_minheight(frp, next_curwin);
3256 	    if (n > m)
3257 		m = n;
3258 	}
3259     }
3260     else
3261     {
3262 	/* Add up the minimal heights for all frames in this column. */
3263 	m = 0;
3264 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3265 	    m += frame_minheight(frp, next_curwin);
3266     }
3267 
3268     return m;
3269 }
3270 
3271 /*
3272  * Compute the minimal width for frame "topfrp".
3273  * When "next_curwin" isn't NULL, use p_wiw for this window.
3274  * When "next_curwin" is NOWIN, don't use at least one column for the current
3275  * window.
3276  */
3277     static int
3278 frame_minwidth(
3279     frame_T	*topfrp,
3280     win_T	*next_curwin)	/* use p_wh and p_wiw for next_curwin */
3281 {
3282     frame_T	*frp;
3283     int		m, n;
3284 
3285     if (topfrp->fr_win != NULL)
3286     {
3287 	if (topfrp->fr_win == next_curwin)
3288 	    m = p_wiw + topfrp->fr_win->w_vsep_width;
3289 	else
3290 	{
3291 	    /* window: minimal width of the window plus separator column */
3292 	    m = p_wmw + topfrp->fr_win->w_vsep_width;
3293 	    /* Current window is minimal one column wide */
3294 	    if (p_wmw == 0 && topfrp->fr_win == curwin && next_curwin == NULL)
3295 		++m;
3296 	}
3297     }
3298     else if (topfrp->fr_layout == FR_COL)
3299     {
3300 	/* get the minimal width from each frame in this column */
3301 	m = 0;
3302 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3303 	{
3304 	    n = frame_minwidth(frp, next_curwin);
3305 	    if (n > m)
3306 		m = n;
3307 	}
3308     }
3309     else
3310     {
3311 	/* Add up the minimal widths for all frames in this row. */
3312 	m = 0;
3313 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
3314 	    m += frame_minwidth(frp, next_curwin);
3315     }
3316 
3317     return m;
3318 }
3319 
3320 
3321 /*
3322  * Try to close all windows except current one.
3323  * Buffers in the other windows become hidden if 'hidden' is set, or '!' is
3324  * used and the buffer was modified.
3325  *
3326  * Used by ":bdel" and ":only".
3327  */
3328     void
3329 close_others(
3330     int		message,
3331     int		forceit)	    /* always hide all other windows */
3332 {
3333     win_T	*wp;
3334     win_T	*nextwp;
3335     int		r;
3336 
3337     if (one_window())
3338     {
3339 	if (message
3340 #ifdef FEAT_AUTOCMD
3341 		    && !autocmd_busy
3342 #endif
3343 				    )
3344 	    MSG(_(m_onlyone));
3345 	return;
3346     }
3347 
3348     /* Be very careful here: autocommands may change the window layout. */
3349     for (wp = firstwin; win_valid(wp); wp = nextwp)
3350     {
3351 	nextwp = wp->w_next;
3352 	if (wp != curwin)		/* don't close current window */
3353 	{
3354 
3355 	    /* Check if it's allowed to abandon this window */
3356 	    r = can_abandon(wp->w_buffer, forceit);
3357 #ifdef FEAT_AUTOCMD
3358 	    if (!win_valid(wp))		/* autocommands messed wp up */
3359 	    {
3360 		nextwp = firstwin;
3361 		continue;
3362 	    }
3363 #endif
3364 	    if (!r)
3365 	    {
3366 #if defined(FEAT_GUI_DIALOG) || defined(FEAT_CON_DIALOG)
3367 		if (message && (p_confirm || cmdmod.confirm) && p_write)
3368 		{
3369 		    dialog_changed(wp->w_buffer, FALSE);
3370 # ifdef FEAT_AUTOCMD
3371 		    if (!win_valid(wp))		/* autocommands messed wp up */
3372 		    {
3373 			nextwp = firstwin;
3374 			continue;
3375 		    }
3376 # endif
3377 		}
3378 		if (bufIsChanged(wp->w_buffer))
3379 #endif
3380 		    continue;
3381 	    }
3382 	    win_close(wp, !buf_hide(wp->w_buffer)
3383 					       && !bufIsChanged(wp->w_buffer));
3384 	}
3385     }
3386 
3387     if (message && !ONE_WINDOW)
3388 	EMSG(_("E445: Other window contains changes"));
3389 }
3390 
3391 #endif /* FEAT_WINDOWS */
3392 
3393 /*
3394  * Init the current window "curwin".
3395  * Called when a new file is being edited.
3396  */
3397     void
3398 curwin_init(void)
3399 {
3400     win_init_empty(curwin);
3401 }
3402 
3403     void
3404 win_init_empty(win_T *wp)
3405 {
3406     redraw_win_later(wp, NOT_VALID);
3407     wp->w_lines_valid = 0;
3408     wp->w_cursor.lnum = 1;
3409     wp->w_curswant = wp->w_cursor.col = 0;
3410 #ifdef FEAT_VIRTUALEDIT
3411     wp->w_cursor.coladd = 0;
3412 #endif
3413     wp->w_pcmark.lnum = 1;	/* pcmark not cleared but set to line 1 */
3414     wp->w_pcmark.col = 0;
3415     wp->w_prev_pcmark.lnum = 0;
3416     wp->w_prev_pcmark.col = 0;
3417     wp->w_topline = 1;
3418 #ifdef FEAT_DIFF
3419     wp->w_topfill = 0;
3420 #endif
3421     wp->w_botline = 2;
3422 #ifdef FEAT_FKMAP
3423     if (wp->w_p_rl)
3424 	wp->w_farsi = W_CONV + W_R_L;
3425     else
3426 	wp->w_farsi = W_CONV;
3427 #endif
3428 #ifdef FEAT_SYN_HL
3429     wp->w_s = &wp->w_buffer->b_s;
3430 #endif
3431 }
3432 
3433 /*
3434  * Allocate the first window and put an empty buffer in it.
3435  * Called from main().
3436  * Return FAIL when something goes wrong (out of memory).
3437  */
3438     int
3439 win_alloc_first(void)
3440 {
3441     if (win_alloc_firstwin(NULL) == FAIL)
3442 	return FAIL;
3443 
3444 #ifdef FEAT_WINDOWS
3445     first_tabpage = alloc_tabpage();
3446     if (first_tabpage == NULL)
3447 	return FAIL;
3448     first_tabpage->tp_topframe = topframe;
3449     curtab = first_tabpage;
3450 #endif
3451 
3452     return OK;
3453 }
3454 
3455 #if defined(FEAT_AUTOCMD) || defined(PROTO)
3456 /*
3457  * Init "aucmd_win".  This can only be done after the first
3458  * window is fully initialized, thus it can't be in win_alloc_first().
3459  */
3460     void
3461 win_alloc_aucmd_win(void)
3462 {
3463     aucmd_win = win_alloc(NULL, TRUE);
3464     if (aucmd_win != NULL)
3465     {
3466 	win_init_some(aucmd_win, curwin);
3467 	RESET_BINDING(aucmd_win);
3468 	new_frame(aucmd_win);
3469     }
3470 }
3471 #endif
3472 
3473 /*
3474  * Allocate the first window or the first window in a new tab page.
3475  * When "oldwin" is NULL create an empty buffer for it.
3476  * When "oldwin" is not NULL copy info from it to the new window (only with
3477  * FEAT_WINDOWS).
3478  * Return FAIL when something goes wrong (out of memory).
3479  */
3480     static int
3481 win_alloc_firstwin(win_T *oldwin)
3482 {
3483     curwin = win_alloc(NULL, FALSE);
3484     if (oldwin == NULL)
3485     {
3486 	/* Very first window, need to create an empty buffer for it and
3487 	 * initialize from scratch. */
3488 	curbuf = buflist_new(NULL, NULL, 1L, BLN_LISTED);
3489 	if (curwin == NULL || curbuf == NULL)
3490 	    return FAIL;
3491 	curwin->w_buffer = curbuf;
3492 #ifdef FEAT_SYN_HL
3493 	curwin->w_s = &(curbuf->b_s);
3494 #endif
3495 	curbuf->b_nwindows = 1;	/* there is one window */
3496 #ifdef FEAT_WINDOWS
3497 	curwin->w_alist = &global_alist;
3498 #endif
3499 	curwin_init();		/* init current window */
3500     }
3501 #ifdef FEAT_WINDOWS
3502     else
3503     {
3504 	/* First window in new tab page, initialize it from "oldwin". */
3505 	win_init(curwin, oldwin, 0);
3506 
3507 	/* We don't want cursor- and scroll-binding in the first window. */
3508 	RESET_BINDING(curwin);
3509     }
3510 #endif
3511 
3512     new_frame(curwin);
3513     if (curwin->w_frame == NULL)
3514 	return FAIL;
3515     topframe = curwin->w_frame;
3516 #ifdef FEAT_WINDOWS
3517     topframe->fr_width = Columns;
3518 #endif
3519     topframe->fr_height = Rows - p_ch;
3520     topframe->fr_win = curwin;
3521 
3522     return OK;
3523 }
3524 
3525 /*
3526  * Create a frame for window "wp".
3527  */
3528     static void
3529 new_frame(win_T *wp)
3530 {
3531     frame_T *frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
3532 
3533     wp->w_frame = frp;
3534     if (frp != NULL)
3535     {
3536 	frp->fr_layout = FR_LEAF;
3537 	frp->fr_win = wp;
3538     }
3539 }
3540 
3541 /*
3542  * Initialize the window and frame size to the maximum.
3543  */
3544     void
3545 win_init_size(void)
3546 {
3547     firstwin->w_height = ROWS_AVAIL;
3548     topframe->fr_height = ROWS_AVAIL;
3549 #ifdef FEAT_WINDOWS
3550     firstwin->w_width = Columns;
3551     topframe->fr_width = Columns;
3552 #endif
3553 }
3554 
3555 #if defined(FEAT_WINDOWS) || defined(PROTO)
3556 
3557 /*
3558  * Allocate a new tabpage_T and init the values.
3559  * Returns NULL when out of memory.
3560  */
3561     static tabpage_T *
3562 alloc_tabpage(void)
3563 {
3564     tabpage_T	*tp;
3565 # ifdef FEAT_GUI
3566     int		i;
3567 # endif
3568 
3569 
3570     tp = (tabpage_T *)alloc_clear((unsigned)sizeof(tabpage_T));
3571     if (tp == NULL)
3572 	return NULL;
3573 
3574 # ifdef FEAT_EVAL
3575     /* init t: variables */
3576     tp->tp_vars = dict_alloc();
3577     if (tp->tp_vars == NULL)
3578     {
3579 	vim_free(tp);
3580 	return NULL;
3581     }
3582     init_var_dict(tp->tp_vars, &tp->tp_winvar, VAR_SCOPE);
3583 # endif
3584 
3585 # ifdef FEAT_GUI
3586     for (i = 0; i < 3; i++)
3587 	tp->tp_prev_which_scrollbars[i] = -1;
3588 # endif
3589 # ifdef FEAT_DIFF
3590     tp->tp_diff_invalid = TRUE;
3591 # endif
3592     tp->tp_ch_used = p_ch;
3593 
3594     return tp;
3595 }
3596 
3597     void
3598 free_tabpage(tabpage_T *tp)
3599 {
3600     int idx;
3601 
3602 # ifdef FEAT_DIFF
3603     diff_clear(tp);
3604 # endif
3605     for (idx = 0; idx < SNAP_COUNT; ++idx)
3606 	clear_snapshot(tp, idx);
3607 #ifdef FEAT_EVAL
3608     vars_clear(&tp->tp_vars->dv_hashtab);	/* free all t: variables */
3609     hash_init(&tp->tp_vars->dv_hashtab);
3610     unref_var_dict(tp->tp_vars);
3611 #endif
3612 
3613 #ifdef FEAT_PYTHON
3614     python_tabpage_free(tp);
3615 #endif
3616 
3617 #ifdef FEAT_PYTHON3
3618     python3_tabpage_free(tp);
3619 #endif
3620 
3621     vim_free(tp);
3622 }
3623 
3624 /*
3625  * Create a new Tab page with one window.
3626  * It will edit the current buffer, like after ":split".
3627  * When "after" is 0 put it just after the current Tab page.
3628  * Otherwise put it just before tab page "after".
3629  * Return FAIL or OK.
3630  */
3631     int
3632 win_new_tabpage(int after)
3633 {
3634     tabpage_T	*tp = curtab;
3635     tabpage_T	*newtp;
3636     int		n;
3637 
3638     newtp = alloc_tabpage();
3639     if (newtp == NULL)
3640 	return FAIL;
3641 
3642     /* Remember the current windows in this Tab page. */
3643     if (leave_tabpage(curbuf, TRUE) == FAIL)
3644     {
3645 	vim_free(newtp);
3646 	return FAIL;
3647     }
3648     curtab = newtp;
3649 
3650     /* Create a new empty window. */
3651     if (win_alloc_firstwin(tp->tp_curwin) == OK)
3652     {
3653 	/* Make the new Tab page the new topframe. */
3654 	if (after == 1)
3655 	{
3656 	    /* New tab page becomes the first one. */
3657 	    newtp->tp_next = first_tabpage;
3658 	    first_tabpage = newtp;
3659 	}
3660 	else
3661 	{
3662 	    if (after > 0)
3663 	    {
3664 		/* Put new tab page before tab page "after". */
3665 		n = 2;
3666 		for (tp = first_tabpage; tp->tp_next != NULL
3667 					       && n < after; tp = tp->tp_next)
3668 		    ++n;
3669 	    }
3670 	    newtp->tp_next = tp->tp_next;
3671 	    tp->tp_next = newtp;
3672 	}
3673 	win_init_size();
3674 	firstwin->w_winrow = tabline_height();
3675 	win_comp_scroll(curwin);
3676 
3677 	newtp->tp_topframe = topframe;
3678 	last_status(FALSE);
3679 
3680 #if defined(FEAT_GUI)
3681 	/* When 'guioptions' includes 'L' or 'R' may have to remove or add
3682 	 * scrollbars.  Have to update them anyway. */
3683 	gui_may_update_scrollbars();
3684 #endif
3685 
3686 	redraw_all_later(CLEAR);
3687 #ifdef FEAT_AUTOCMD
3688 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
3689 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
3690 	apply_autocmds(EVENT_TABNEW, NULL, NULL, FALSE, curbuf);
3691 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3692 #endif
3693 	return OK;
3694     }
3695 
3696     /* Failed, get back the previous Tab page */
3697     enter_tabpage(curtab, curbuf, TRUE, TRUE);
3698     return FAIL;
3699 }
3700 
3701 /*
3702  * Open a new tab page if ":tab cmd" was used.  It will edit the same buffer,
3703  * like with ":split".
3704  * Returns OK if a new tab page was created, FAIL otherwise.
3705  */
3706     int
3707 may_open_tabpage(void)
3708 {
3709     int		n = (cmdmod.tab == 0) ? postponed_split_tab : cmdmod.tab;
3710 
3711     if (n != 0)
3712     {
3713 	cmdmod.tab = 0;	    /* reset it to avoid doing it twice */
3714 	postponed_split_tab = 0;
3715 	return win_new_tabpage(n);
3716     }
3717     return FAIL;
3718 }
3719 
3720 /*
3721  * Create up to "maxcount" tabpages with empty windows.
3722  * Returns the number of resulting tab pages.
3723  */
3724     int
3725 make_tabpages(int maxcount)
3726 {
3727     int		count = maxcount;
3728     int		todo;
3729 
3730     /* Limit to 'tabpagemax' tabs. */
3731     if (count > p_tpm)
3732 	count = p_tpm;
3733 
3734 #ifdef FEAT_AUTOCMD
3735     /*
3736      * Don't execute autocommands while creating the tab pages.  Must do that
3737      * when putting the buffers in the windows.
3738      */
3739     block_autocmds();
3740 #endif
3741 
3742     for (todo = count - 1; todo > 0; --todo)
3743 	if (win_new_tabpage(0) == FAIL)
3744 	    break;
3745 
3746 #ifdef FEAT_AUTOCMD
3747     unblock_autocmds();
3748 #endif
3749 
3750     /* return actual number of tab pages */
3751     return (count - todo);
3752 }
3753 
3754 /*
3755  * Return TRUE when "tpc" points to a valid tab page.
3756  */
3757     int
3758 valid_tabpage(tabpage_T *tpc)
3759 {
3760     tabpage_T	*tp;
3761 
3762     FOR_ALL_TABPAGES(tp)
3763 	if (tp == tpc)
3764 	    return TRUE;
3765     return FALSE;
3766 }
3767 
3768 /*
3769  * Return TRUE when "tpc" points to a valid tab page and at least one window is
3770  * valid.
3771  */
3772     int
3773 valid_tabpage_win(tabpage_T *tpc)
3774 {
3775     tabpage_T	*tp;
3776     win_T	*wp;
3777 
3778     FOR_ALL_TABPAGES(tp)
3779     {
3780 	if (tp == tpc)
3781 	{
3782 	    FOR_ALL_WINDOWS_IN_TAB(tp, wp)
3783 	    {
3784 		if (win_valid_any_tab(wp))
3785 		    return TRUE;
3786 	    }
3787 	    return FALSE;
3788 	}
3789     }
3790     /* shouldn't happen */
3791     return FALSE;
3792 }
3793 
3794 /*
3795  * Close tabpage "tab", assuming it has no windows in it.
3796  * There must be another tabpage or this will crash.
3797  */
3798     void
3799 close_tabpage(tabpage_T *tab)
3800 {
3801     tabpage_T	*ptp;
3802 
3803     if (tab == first_tabpage)
3804     {
3805 	first_tabpage = tab->tp_next;
3806 	ptp = first_tabpage;
3807     }
3808     else
3809     {
3810 	for (ptp = first_tabpage; ptp != NULL && ptp->tp_next != tab;
3811 							    ptp = ptp->tp_next)
3812 	    ;
3813 	assert(ptp != NULL);
3814 	ptp->tp_next = tab->tp_next;
3815     }
3816 
3817     goto_tabpage_tp(ptp, FALSE, FALSE);
3818     free_tabpage(tab);
3819 }
3820 
3821 /*
3822  * Find tab page "n" (first one is 1).  Returns NULL when not found.
3823  */
3824     tabpage_T *
3825 find_tabpage(int n)
3826 {
3827     tabpage_T	*tp;
3828     int		i = 1;
3829 
3830     for (tp = first_tabpage; tp != NULL && i != n; tp = tp->tp_next)
3831 	++i;
3832     return tp;
3833 }
3834 
3835 /*
3836  * Get index of tab page "tp".  First one has index 1.
3837  * When not found returns number of tab pages plus one.
3838  */
3839     int
3840 tabpage_index(tabpage_T *ftp)
3841 {
3842     int		i = 1;
3843     tabpage_T	*tp;
3844 
3845     for (tp = first_tabpage; tp != NULL && tp != ftp; tp = tp->tp_next)
3846 	++i;
3847     return i;
3848 }
3849 
3850 /*
3851  * Prepare for leaving the current tab page.
3852  * When autocommands change "curtab" we don't leave the tab page and return
3853  * FAIL.
3854  * Careful: When OK is returned need to get a new tab page very very soon!
3855  */
3856     static int
3857 leave_tabpage(
3858     buf_T	*new_curbuf UNUSED,    /* what is going to be the new curbuf,
3859 				       NULL if unknown */
3860     int		trigger_leave_autocmds UNUSED)
3861 {
3862     tabpage_T	*tp = curtab;
3863 
3864     reset_VIsual_and_resel();	/* stop Visual mode */
3865 #ifdef FEAT_AUTOCMD
3866     if (trigger_leave_autocmds)
3867     {
3868 	if (new_curbuf != curbuf)
3869 	{
3870 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
3871 	    if (curtab != tp)
3872 		return FAIL;
3873 	}
3874 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
3875 	if (curtab != tp)
3876 	    return FAIL;
3877 	apply_autocmds(EVENT_TABLEAVE, NULL, NULL, FALSE, curbuf);
3878 	if (curtab != tp)
3879 	    return FAIL;
3880     }
3881 #endif
3882 #if defined(FEAT_GUI)
3883     /* Remove the scrollbars.  They may be added back later. */
3884     if (gui.in_use)
3885 	gui_remove_scrollbars();
3886 #endif
3887     tp->tp_curwin = curwin;
3888     tp->tp_prevwin = prevwin;
3889     tp->tp_firstwin = firstwin;
3890     tp->tp_lastwin = lastwin;
3891     tp->tp_old_Rows = Rows;
3892     tp->tp_old_Columns = Columns;
3893     firstwin = NULL;
3894     lastwin = NULL;
3895     return OK;
3896 }
3897 
3898 /*
3899  * Start using tab page "tp".
3900  * Only to be used after leave_tabpage() or freeing the current tab page.
3901  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
3902  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
3903  */
3904     static void
3905 enter_tabpage(
3906     tabpage_T	*tp,
3907     buf_T	*old_curbuf UNUSED,
3908     int		trigger_enter_autocmds,
3909     int		trigger_leave_autocmds)
3910 {
3911     int		old_off = tp->tp_firstwin->w_winrow;
3912     win_T	*next_prevwin = tp->tp_prevwin;
3913 
3914     curtab = tp;
3915     firstwin = tp->tp_firstwin;
3916     lastwin = tp->tp_lastwin;
3917     topframe = tp->tp_topframe;
3918 
3919     /* We would like doing the TabEnter event first, but we don't have a
3920      * valid current window yet, which may break some commands.
3921      * This triggers autocommands, thus may make "tp" invalid. */
3922     win_enter_ext(tp->tp_curwin, FALSE, TRUE, FALSE,
3923 			      trigger_enter_autocmds, trigger_leave_autocmds);
3924     prevwin = next_prevwin;
3925 
3926     last_status(FALSE);		/* status line may appear or disappear */
3927     (void)win_comp_pos();	/* recompute w_winrow for all windows */
3928     must_redraw = CLEAR;	/* need to redraw everything */
3929 #ifdef FEAT_DIFF
3930     diff_need_scrollbind = TRUE;
3931 #endif
3932 
3933     /* The tabpage line may have appeared or disappeared, may need to resize
3934      * the frames for that.  When the Vim window was resized need to update
3935      * frame sizes too.  Use the stored value of p_ch, so that it can be
3936      * different for each tab page. */
3937     p_ch = curtab->tp_ch_used;
3938     if (curtab->tp_old_Rows != Rows || (old_off != firstwin->w_winrow
3939 #ifdef FEAT_GUI_TABLINE
3940 			    && !gui_use_tabline()
3941 #endif
3942 		))
3943 	shell_new_rows();
3944     if (curtab->tp_old_Columns != Columns && starting == 0)
3945 	shell_new_columns();	/* update window widths */
3946 
3947 #if defined(FEAT_GUI)
3948     /* When 'guioptions' includes 'L' or 'R' may have to remove or add
3949      * scrollbars.  Have to update them anyway. */
3950     gui_may_update_scrollbars();
3951 #endif
3952 
3953 #ifdef FEAT_AUTOCMD
3954     /* Apply autocommands after updating the display, when 'rows' and
3955      * 'columns' have been set correctly. */
3956     if (trigger_enter_autocmds)
3957     {
3958 	apply_autocmds(EVENT_TABENTER, NULL, NULL, FALSE, curbuf);
3959 	if (old_curbuf != curbuf)
3960 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
3961     }
3962 #endif
3963 
3964     redraw_all_later(CLEAR);
3965 }
3966 
3967 /*
3968  * Go to tab page "n".  For ":tab N" and "Ngt".
3969  * When "n" is 9999 go to the last tab page.
3970  */
3971     void
3972 goto_tabpage(int n)
3973 {
3974     tabpage_T	*tp;
3975     tabpage_T	*ttp;
3976     int		i;
3977 
3978     if (text_locked())
3979     {
3980 	/* Not allowed when editing the command line. */
3981 	text_locked_msg();
3982 	return;
3983     }
3984 
3985     /* If there is only one it can't work. */
3986     if (first_tabpage->tp_next == NULL)
3987     {
3988 	if (n > 1)
3989 	    beep_flush();
3990 	return;
3991     }
3992 
3993     if (n == 0)
3994     {
3995 	/* No count, go to next tab page, wrap around end. */
3996 	if (curtab->tp_next == NULL)
3997 	    tp = first_tabpage;
3998 	else
3999 	    tp = curtab->tp_next;
4000     }
4001     else if (n < 0)
4002     {
4003 	/* "gT": go to previous tab page, wrap around end.  "N gT" repeats
4004 	 * this N times. */
4005 	ttp = curtab;
4006 	for (i = n; i < 0; ++i)
4007 	{
4008 	    for (tp = first_tabpage; tp->tp_next != ttp && tp->tp_next != NULL;
4009 		    tp = tp->tp_next)
4010 		;
4011 	    ttp = tp;
4012 	}
4013     }
4014     else if (n == 9999)
4015     {
4016 	/* Go to last tab page. */
4017 	for (tp = first_tabpage; tp->tp_next != NULL; tp = tp->tp_next)
4018 	    ;
4019     }
4020     else
4021     {
4022 	/* Go to tab page "n". */
4023 	tp = find_tabpage(n);
4024 	if (tp == NULL)
4025 	{
4026 	    beep_flush();
4027 	    return;
4028 	}
4029     }
4030 
4031     goto_tabpage_tp(tp, TRUE, TRUE);
4032 
4033 #ifdef FEAT_GUI_TABLINE
4034     if (gui_use_tabline())
4035 	gui_mch_set_curtab(tabpage_index(curtab));
4036 #endif
4037 }
4038 
4039 /*
4040  * Go to tabpage "tp".
4041  * Only trigger *Enter autocommands when trigger_enter_autocmds is TRUE.
4042  * Only trigger *Leave autocommands when trigger_leave_autocmds is TRUE.
4043  * Note: doesn't update the GUI tab.
4044  */
4045     void
4046 goto_tabpage_tp(
4047     tabpage_T	*tp,
4048     int		trigger_enter_autocmds,
4049     int		trigger_leave_autocmds)
4050 {
4051     /* Don't repeat a message in another tab page. */
4052     set_keep_msg(NULL, 0);
4053 
4054     if (tp != curtab && leave_tabpage(tp->tp_curwin->w_buffer,
4055 					trigger_leave_autocmds) == OK)
4056     {
4057 	if (valid_tabpage(tp))
4058 	    enter_tabpage(tp, curbuf, trigger_enter_autocmds,
4059 		    trigger_leave_autocmds);
4060 	else
4061 	    enter_tabpage(curtab, curbuf, trigger_enter_autocmds,
4062 		    trigger_leave_autocmds);
4063     }
4064 }
4065 
4066 /*
4067  * Enter window "wp" in tab page "tp".
4068  * Also updates the GUI tab.
4069  */
4070     void
4071 goto_tabpage_win(tabpage_T *tp, win_T *wp)
4072 {
4073     goto_tabpage_tp(tp, TRUE, TRUE);
4074     if (curtab == tp && win_valid(wp))
4075     {
4076 	win_enter(wp, TRUE);
4077 # ifdef FEAT_GUI_TABLINE
4078 	if (gui_use_tabline())
4079 	    gui_mch_set_curtab(tabpage_index(curtab));
4080 # endif
4081     }
4082 }
4083 
4084 /*
4085  * Move the current tab page to after tab page "nr".
4086  */
4087     void
4088 tabpage_move(int nr)
4089 {
4090     int		n = 1;
4091     tabpage_T	*tp, *tp_dst;
4092 
4093     if (first_tabpage->tp_next == NULL)
4094 	return;
4095 
4096     for (tp = first_tabpage; tp->tp_next != NULL && n < nr; tp = tp->tp_next)
4097 	++n;
4098 
4099     if (tp == curtab || (nr > 0 && tp->tp_next != NULL
4100 						    && tp->tp_next == curtab))
4101 	return;
4102 
4103     tp_dst = tp;
4104 
4105     /* Remove the current tab page from the list of tab pages. */
4106     if (curtab == first_tabpage)
4107 	first_tabpage = curtab->tp_next;
4108     else
4109     {
4110 	FOR_ALL_TABPAGES(tp)
4111 	    if (tp->tp_next == curtab)
4112 		break;
4113 	if (tp == NULL)	/* "cannot happen" */
4114 	    return;
4115 	tp->tp_next = curtab->tp_next;
4116     }
4117 
4118     /* Re-insert it at the specified position. */
4119     if (nr <= 0)
4120     {
4121 	curtab->tp_next = first_tabpage;
4122 	first_tabpage = curtab;
4123     }
4124     else
4125     {
4126 	curtab->tp_next = tp_dst->tp_next;
4127 	tp_dst->tp_next = curtab;
4128     }
4129 
4130     /* Need to redraw the tabline.  Tab page contents doesn't change. */
4131     redraw_tabline = TRUE;
4132 }
4133 
4134 
4135 /*
4136  * Go to another window.
4137  * When jumping to another buffer, stop Visual mode.  Do this before
4138  * changing windows so we can yank the selection into the '*' register.
4139  * When jumping to another window on the same buffer, adjust its cursor
4140  * position to keep the same Visual area.
4141  */
4142     void
4143 win_goto(win_T *wp)
4144 {
4145 #ifdef FEAT_CONCEAL
4146     win_T	*owp = curwin;
4147 #endif
4148 
4149     if (text_locked())
4150     {
4151 	beep_flush();
4152 	text_locked_msg();
4153 	return;
4154     }
4155 #ifdef FEAT_AUTOCMD
4156     if (curbuf_locked())
4157 	return;
4158 #endif
4159 
4160     if (wp->w_buffer != curbuf)
4161 	reset_VIsual_and_resel();
4162     else if (VIsual_active)
4163 	wp->w_cursor = curwin->w_cursor;
4164 
4165 #ifdef FEAT_GUI
4166     need_mouse_correct = TRUE;
4167 #endif
4168     win_enter(wp, TRUE);
4169 
4170 #ifdef FEAT_CONCEAL
4171     /* Conceal cursor line in previous window, unconceal in current window. */
4172     if (win_valid(owp) && owp->w_p_cole > 0 && !msg_scrolled)
4173 	update_single_line(owp, owp->w_cursor.lnum);
4174     if (curwin->w_p_cole > 0 && !msg_scrolled)
4175 	need_cursor_line_redraw = TRUE;
4176 #endif
4177 }
4178 
4179 #if defined(FEAT_PERL) || defined(PROTO)
4180 /*
4181  * Find window number "winnr" (counting top to bottom).
4182  */
4183     win_T *
4184 win_find_nr(int winnr)
4185 {
4186     win_T	*wp;
4187 
4188 # ifdef FEAT_WINDOWS
4189     FOR_ALL_WINDOWS(wp)
4190 	if (--winnr == 0)
4191 	    break;
4192     return wp;
4193 # else
4194     return curwin;
4195 # endif
4196 }
4197 #endif
4198 
4199 #if (defined(FEAT_WINDOWS) && (defined(FEAT_PYTHON) || defined(FEAT_PYTHON3))) \
4200 	|| defined(PROTO)
4201 /*
4202  * Find the tabpage for window "win".
4203  */
4204     tabpage_T *
4205 win_find_tabpage(win_T *win)
4206 {
4207     win_T	*wp;
4208     tabpage_T	*tp;
4209 
4210     FOR_ALL_TAB_WINDOWS(tp, wp)
4211 	    if (wp == win)
4212 		return tp;
4213     return NULL;
4214 }
4215 #endif
4216 
4217 /*
4218  * Move to window above or below "count" times.
4219  */
4220     static void
4221 win_goto_ver(
4222     int		up,		/* TRUE to go to win above */
4223     long	count)
4224 {
4225     frame_T	*fr;
4226     frame_T	*nfr;
4227     frame_T	*foundfr;
4228 
4229     foundfr = curwin->w_frame;
4230     while (count--)
4231     {
4232 	/*
4233 	 * First go upwards in the tree of frames until we find a upwards or
4234 	 * downwards neighbor.
4235 	 */
4236 	fr = foundfr;
4237 	for (;;)
4238 	{
4239 	    if (fr == topframe)
4240 		goto end;
4241 	    if (up)
4242 		nfr = fr->fr_prev;
4243 	    else
4244 		nfr = fr->fr_next;
4245 	    if (fr->fr_parent->fr_layout == FR_COL && nfr != NULL)
4246 		break;
4247 	    fr = fr->fr_parent;
4248 	}
4249 
4250 	/*
4251 	 * Now go downwards to find the bottom or top frame in it.
4252 	 */
4253 	for (;;)
4254 	{
4255 	    if (nfr->fr_layout == FR_LEAF)
4256 	    {
4257 		foundfr = nfr;
4258 		break;
4259 	    }
4260 	    fr = nfr->fr_child;
4261 	    if (nfr->fr_layout == FR_ROW)
4262 	    {
4263 		/* Find the frame at the cursor row. */
4264 		while (fr->fr_next != NULL
4265 			&& frame2win(fr)->w_wincol + fr->fr_width
4266 					 <= curwin->w_wincol + curwin->w_wcol)
4267 		    fr = fr->fr_next;
4268 	    }
4269 	    if (nfr->fr_layout == FR_COL && up)
4270 		while (fr->fr_next != NULL)
4271 		    fr = fr->fr_next;
4272 	    nfr = fr;
4273 	}
4274     }
4275 end:
4276     if (foundfr != NULL)
4277 	win_goto(foundfr->fr_win);
4278 }
4279 
4280 /*
4281  * Move to left or right window.
4282  */
4283     static void
4284 win_goto_hor(
4285     int		left,		/* TRUE to go to left win */
4286     long	count)
4287 {
4288     frame_T	*fr;
4289     frame_T	*nfr;
4290     frame_T	*foundfr;
4291 
4292     foundfr = curwin->w_frame;
4293     while (count--)
4294     {
4295 	/*
4296 	 * First go upwards in the tree of frames until we find a left or
4297 	 * right neighbor.
4298 	 */
4299 	fr = foundfr;
4300 	for (;;)
4301 	{
4302 	    if (fr == topframe)
4303 		goto end;
4304 	    if (left)
4305 		nfr = fr->fr_prev;
4306 	    else
4307 		nfr = fr->fr_next;
4308 	    if (fr->fr_parent->fr_layout == FR_ROW && nfr != NULL)
4309 		break;
4310 	    fr = fr->fr_parent;
4311 	}
4312 
4313 	/*
4314 	 * Now go downwards to find the leftmost or rightmost frame in it.
4315 	 */
4316 	for (;;)
4317 	{
4318 	    if (nfr->fr_layout == FR_LEAF)
4319 	    {
4320 		foundfr = nfr;
4321 		break;
4322 	    }
4323 	    fr = nfr->fr_child;
4324 	    if (nfr->fr_layout == FR_COL)
4325 	    {
4326 		/* Find the frame at the cursor row. */
4327 		while (fr->fr_next != NULL
4328 			&& frame2win(fr)->w_winrow + fr->fr_height
4329 					 <= curwin->w_winrow + curwin->w_wrow)
4330 		    fr = fr->fr_next;
4331 	    }
4332 	    if (nfr->fr_layout == FR_ROW && left)
4333 		while (fr->fr_next != NULL)
4334 		    fr = fr->fr_next;
4335 	    nfr = fr;
4336 	}
4337     }
4338 end:
4339     if (foundfr != NULL)
4340 	win_goto(foundfr->fr_win);
4341 }
4342 
4343 /*
4344  * Make window "wp" the current window.
4345  */
4346     void
4347 win_enter(win_T *wp, int undo_sync)
4348 {
4349     win_enter_ext(wp, undo_sync, FALSE, FALSE, TRUE, TRUE);
4350 }
4351 
4352 /*
4353  * Make window wp the current window.
4354  * Can be called with "curwin_invalid" TRUE, which means that curwin has just
4355  * been closed and isn't valid.
4356  */
4357     static void
4358 win_enter_ext(
4359     win_T	*wp,
4360     int		undo_sync,
4361     int		curwin_invalid,
4362     int		trigger_new_autocmds UNUSED,
4363     int		trigger_enter_autocmds UNUSED,
4364     int		trigger_leave_autocmds UNUSED)
4365 {
4366 #ifdef FEAT_AUTOCMD
4367     int		other_buffer = FALSE;
4368 #endif
4369 
4370     if (wp == curwin && !curwin_invalid)	/* nothing to do */
4371 	return;
4372 
4373 #ifdef FEAT_AUTOCMD
4374     if (!curwin_invalid && trigger_leave_autocmds)
4375     {
4376 	/*
4377 	 * Be careful: If autocommands delete the window, return now.
4378 	 */
4379 	if (wp->w_buffer != curbuf)
4380 	{
4381 	    apply_autocmds(EVENT_BUFLEAVE, NULL, NULL, FALSE, curbuf);
4382 	    other_buffer = TRUE;
4383 	    if (!win_valid(wp))
4384 		return;
4385 	}
4386 	apply_autocmds(EVENT_WINLEAVE, NULL, NULL, FALSE, curbuf);
4387 	if (!win_valid(wp))
4388 	    return;
4389 # ifdef FEAT_EVAL
4390 	/* autocmds may abort script processing */
4391 	if (aborting())
4392 	    return;
4393 # endif
4394     }
4395 #endif
4396 
4397     /* sync undo before leaving the current buffer */
4398     if (undo_sync && curbuf != wp->w_buffer)
4399 	u_sync(FALSE);
4400 
4401     /* Might need to scroll the old window before switching, e.g., when the
4402      * cursor was moved. */
4403     update_topline();
4404 
4405     /* may have to copy the buffer options when 'cpo' contains 'S' */
4406     if (wp->w_buffer != curbuf)
4407 	buf_copy_options(wp->w_buffer, BCO_ENTER | BCO_NOHELP);
4408     if (!curwin_invalid)
4409     {
4410 	prevwin = curwin;	/* remember for CTRL-W p */
4411 	curwin->w_redr_status = TRUE;
4412     }
4413     curwin = wp;
4414     curbuf = wp->w_buffer;
4415     check_cursor();
4416 #ifdef FEAT_VIRTUALEDIT
4417     if (!virtual_active())
4418 	curwin->w_cursor.coladd = 0;
4419 #endif
4420     changed_line_abv_curs();	/* assume cursor position needs updating */
4421 
4422     if (curwin->w_localdir != NULL)
4423     {
4424 	/* Window has a local directory: Save current directory as global
4425 	 * directory (unless that was done already) and change to the local
4426 	 * directory. */
4427 	if (globaldir == NULL)
4428 	{
4429 	    char_u	cwd[MAXPATHL];
4430 
4431 	    if (mch_dirname(cwd, MAXPATHL) == OK)
4432 		globaldir = vim_strsave(cwd);
4433 	}
4434 	if (mch_chdir((char *)curwin->w_localdir) == 0)
4435 	    shorten_fnames(TRUE);
4436     }
4437     else if (globaldir != NULL)
4438     {
4439 	/* Window doesn't have a local directory and we are not in the global
4440 	 * directory: Change to the global directory. */
4441 	ignored = mch_chdir((char *)globaldir);
4442 	vim_free(globaldir);
4443 	globaldir = NULL;
4444 	shorten_fnames(TRUE);
4445     }
4446 
4447 #ifdef FEAT_AUTOCMD
4448     if (trigger_new_autocmds)
4449 	apply_autocmds(EVENT_WINNEW, NULL, NULL, FALSE, curbuf);
4450     if (trigger_enter_autocmds)
4451     {
4452 	apply_autocmds(EVENT_WINENTER, NULL, NULL, FALSE, curbuf);
4453 	if (other_buffer)
4454 	    apply_autocmds(EVENT_BUFENTER, NULL, NULL, FALSE, curbuf);
4455     }
4456 #endif
4457 
4458 #ifdef FEAT_TITLE
4459     maketitle();
4460 #endif
4461     curwin->w_redr_status = TRUE;
4462     redraw_tabline = TRUE;
4463     if (restart_edit)
4464 	redraw_later(VALID);	/* causes status line redraw */
4465 
4466     /* set window height to desired minimal value */
4467     if (curwin->w_height < p_wh && !curwin->w_p_wfh)
4468 	win_setheight((int)p_wh);
4469     else if (curwin->w_height == 0)
4470 	win_setheight(1);
4471 
4472     /* set window width to desired minimal value */
4473     if (curwin->w_width < p_wiw && !curwin->w_p_wfw)
4474 	win_setwidth((int)p_wiw);
4475 
4476 #ifdef FEAT_MOUSE
4477     setmouse();			/* in case jumped to/from help buffer */
4478 #endif
4479 
4480     /* Change directories when the 'acd' option is set. */
4481     DO_AUTOCHDIR
4482 }
4483 
4484 #endif /* FEAT_WINDOWS */
4485 
4486 #if defined(FEAT_WINDOWS) || defined(FEAT_SIGNS) || defined(PROTO)
4487 /*
4488  * Jump to the first open window that contains buffer "buf", if one exists.
4489  * Returns a pointer to the window found, otherwise NULL.
4490  */
4491     win_T *
4492 buf_jump_open_win(buf_T *buf)
4493 {
4494     win_T	*wp = NULL;
4495 
4496     if (curwin->w_buffer == buf)
4497 	wp = curwin;
4498 # ifdef FEAT_WINDOWS
4499     else
4500 	FOR_ALL_WINDOWS(wp)
4501 	    if (wp->w_buffer == buf)
4502 		break;
4503     if (wp != NULL)
4504 	win_enter(wp, FALSE);
4505 # endif
4506     return wp;
4507 }
4508 
4509 /*
4510  * Jump to the first open window in any tab page that contains buffer "buf",
4511  * if one exists.
4512  * Returns a pointer to the window found, otherwise NULL.
4513  */
4514     win_T *
4515 buf_jump_open_tab(buf_T *buf)
4516 {
4517     win_T	*wp = buf_jump_open_win(buf);
4518 # ifdef FEAT_WINDOWS
4519     tabpage_T	*tp;
4520 
4521     if (wp != NULL)
4522 	return wp;
4523 
4524     FOR_ALL_TABPAGES(tp)
4525 	if (tp != curtab)
4526 	{
4527 	    for (wp = tp->tp_firstwin; wp != NULL; wp = wp->w_next)
4528 		if (wp->w_buffer == buf)
4529 		    break;
4530 	    if (wp != NULL)
4531 	    {
4532 		goto_tabpage_win(tp, wp);
4533 		if (curwin != wp)
4534 		    wp = NULL;	/* something went wrong */
4535 		break;
4536 	    }
4537 	}
4538 # endif
4539     return wp;
4540 }
4541 #endif
4542 
4543 static int last_win_id = LOWEST_WIN_ID - 1;
4544 
4545 /*
4546  * Allocate a window structure and link it in the window list when "hidden" is
4547  * FALSE.
4548  */
4549     static win_T *
4550 win_alloc(win_T *after UNUSED, int hidden UNUSED)
4551 {
4552     win_T	*new_wp;
4553 
4554     /*
4555      * allocate window structure and linesizes arrays
4556      */
4557     new_wp = (win_T *)alloc_clear((unsigned)sizeof(win_T));
4558     if (new_wp == NULL)
4559 	return NULL;
4560 
4561     if (win_alloc_lines(new_wp) == FAIL)
4562     {
4563 	vim_free(new_wp);
4564 	return NULL;
4565     }
4566 
4567     new_wp->w_id = ++last_win_id;
4568 
4569 #ifdef FEAT_EVAL
4570     /* init w: variables */
4571     new_wp->w_vars = dict_alloc();
4572     if (new_wp->w_vars == NULL)
4573     {
4574 	win_free_lsize(new_wp);
4575 	vim_free(new_wp);
4576 	return NULL;
4577     }
4578     init_var_dict(new_wp->w_vars, &new_wp->w_winvar, VAR_SCOPE);
4579 #endif
4580 
4581 #ifdef FEAT_AUTOCMD
4582     /* Don't execute autocommands while the window is not properly
4583      * initialized yet.  gui_create_scrollbar() may trigger a FocusGained
4584      * event. */
4585     block_autocmds();
4586 #endif
4587     /*
4588      * link the window in the window list
4589      */
4590 #ifdef FEAT_WINDOWS
4591     if (!hidden)
4592 	win_append(after, new_wp);
4593     new_wp->w_wincol = 0;
4594     new_wp->w_width = Columns;
4595 #endif
4596 
4597     /* position the display and the cursor at the top of the file. */
4598     new_wp->w_topline = 1;
4599 #ifdef FEAT_DIFF
4600     new_wp->w_topfill = 0;
4601 #endif
4602     new_wp->w_botline = 2;
4603     new_wp->w_cursor.lnum = 1;
4604 #ifdef FEAT_SCROLLBIND
4605     new_wp->w_scbind_pos = 1;
4606 #endif
4607 
4608     /* We won't calculate w_fraction until resizing the window */
4609     new_wp->w_fraction = 0;
4610     new_wp->w_prev_fraction_row = -1;
4611 
4612 #ifdef FEAT_GUI
4613     if (gui.in_use)
4614     {
4615 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_LEFT],
4616 		SBAR_LEFT, new_wp);
4617 	gui_create_scrollbar(&new_wp->w_scrollbars[SBAR_RIGHT],
4618 		SBAR_RIGHT, new_wp);
4619     }
4620 #endif
4621 #ifdef FEAT_FOLDING
4622     foldInitWin(new_wp);
4623 #endif
4624 #ifdef FEAT_AUTOCMD
4625     unblock_autocmds();
4626 #endif
4627 #ifdef FEAT_SEARCH_EXTRA
4628     new_wp->w_match_head = NULL;
4629     new_wp->w_next_match_id = 4;
4630 #endif
4631     return new_wp;
4632 }
4633 
4634 #if defined(FEAT_WINDOWS) || defined(PROTO)
4635 
4636 /*
4637  * Remove window 'wp' from the window list and free the structure.
4638  */
4639     static void
4640 win_free(
4641     win_T	*wp,
4642     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
4643 {
4644     int		i;
4645     buf_T	*buf;
4646     wininfo_T	*wip;
4647 
4648 #ifdef FEAT_FOLDING
4649     clearFolding(wp);
4650 #endif
4651 
4652     /* reduce the reference count to the argument list. */
4653     alist_unlink(wp->w_alist);
4654 
4655 #ifdef FEAT_AUTOCMD
4656     /* Don't execute autocommands while the window is halfway being deleted.
4657      * gui_mch_destroy_scrollbar() may trigger a FocusGained event. */
4658     block_autocmds();
4659 #endif
4660 
4661 #ifdef FEAT_LUA
4662     lua_window_free(wp);
4663 #endif
4664 
4665 #ifdef FEAT_MZSCHEME
4666     mzscheme_window_free(wp);
4667 #endif
4668 
4669 #ifdef FEAT_PERL
4670     perl_win_free(wp);
4671 #endif
4672 
4673 #ifdef FEAT_PYTHON
4674     python_window_free(wp);
4675 #endif
4676 
4677 #ifdef FEAT_PYTHON3
4678     python3_window_free(wp);
4679 #endif
4680 
4681 #ifdef FEAT_TCL
4682     tcl_window_free(wp);
4683 #endif
4684 
4685 #ifdef FEAT_RUBY
4686     ruby_window_free(wp);
4687 #endif
4688 
4689     clear_winopt(&wp->w_onebuf_opt);
4690     clear_winopt(&wp->w_allbuf_opt);
4691 
4692 #ifdef FEAT_EVAL
4693     vars_clear(&wp->w_vars->dv_hashtab);	/* free all w: variables */
4694     hash_init(&wp->w_vars->dv_hashtab);
4695     unref_var_dict(wp->w_vars);
4696 #endif
4697 
4698     {
4699 	tabpage_T	*ttp;
4700 
4701 	if (prevwin == wp)
4702 	    prevwin = NULL;
4703 	FOR_ALL_TABPAGES(ttp)
4704 	    if (ttp->tp_prevwin == wp)
4705 		ttp->tp_prevwin = NULL;
4706     }
4707     win_free_lsize(wp);
4708 
4709     for (i = 0; i < wp->w_tagstacklen; ++i)
4710 	vim_free(wp->w_tagstack[i].tagname);
4711 
4712     vim_free(wp->w_localdir);
4713 
4714     /* Remove the window from the b_wininfo lists, it may happen that the
4715      * freed memory is re-used for another window. */
4716     FOR_ALL_BUFFERS(buf)
4717 	for (wip = buf->b_wininfo; wip != NULL; wip = wip->wi_next)
4718 	    if (wip->wi_win == wp)
4719 		wip->wi_win = NULL;
4720 
4721 #ifdef FEAT_SEARCH_EXTRA
4722     clear_matches(wp);
4723 #endif
4724 
4725 #ifdef FEAT_JUMPLIST
4726     free_jumplist(wp);
4727 #endif
4728 
4729 #ifdef FEAT_QUICKFIX
4730     qf_free_all(wp);
4731 #endif
4732 
4733 #ifdef FEAT_GUI
4734     if (gui.in_use)
4735     {
4736 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_LEFT]);
4737 	gui_mch_destroy_scrollbar(&wp->w_scrollbars[SBAR_RIGHT]);
4738     }
4739 #endif /* FEAT_GUI */
4740 
4741 #ifdef FEAT_SYN_HL
4742     vim_free(wp->w_p_cc_cols);
4743 #endif
4744 
4745 #ifdef FEAT_AUTOCMD
4746     if (wp != aucmd_win)
4747 #endif
4748 	win_remove(wp, tp);
4749 #ifdef FEAT_AUTOCMD
4750     if (autocmd_busy)
4751     {
4752 	wp->w_next = au_pending_free_win;
4753 	au_pending_free_win = wp;
4754     }
4755     else
4756 #endif
4757 	vim_free(wp);
4758 
4759 #ifdef FEAT_AUTOCMD
4760     unblock_autocmds();
4761 #endif
4762 }
4763 
4764 /*
4765  * Append window "wp" in the window list after window "after".
4766  */
4767     void
4768 win_append(win_T *after, win_T *wp)
4769 {
4770     win_T	*before;
4771 
4772     if (after == NULL)	    /* after NULL is in front of the first */
4773 	before = firstwin;
4774     else
4775 	before = after->w_next;
4776 
4777     wp->w_next = before;
4778     wp->w_prev = after;
4779     if (after == NULL)
4780 	firstwin = wp;
4781     else
4782 	after->w_next = wp;
4783     if (before == NULL)
4784 	lastwin = wp;
4785     else
4786 	before->w_prev = wp;
4787 }
4788 
4789 /*
4790  * Remove a window from the window list.
4791  */
4792     void
4793 win_remove(
4794     win_T	*wp,
4795     tabpage_T	*tp)		/* tab page "win" is in, NULL for current */
4796 {
4797     if (wp->w_prev != NULL)
4798 	wp->w_prev->w_next = wp->w_next;
4799     else if (tp == NULL)
4800 	firstwin = wp->w_next;
4801     else
4802 	tp->tp_firstwin = wp->w_next;
4803     if (wp->w_next != NULL)
4804 	wp->w_next->w_prev = wp->w_prev;
4805     else if (tp == NULL)
4806 	lastwin = wp->w_prev;
4807     else
4808 	tp->tp_lastwin = wp->w_prev;
4809 }
4810 
4811 /*
4812  * Append frame "frp" in a frame list after frame "after".
4813  */
4814     static void
4815 frame_append(frame_T *after, frame_T *frp)
4816 {
4817     frp->fr_next = after->fr_next;
4818     after->fr_next = frp;
4819     if (frp->fr_next != NULL)
4820 	frp->fr_next->fr_prev = frp;
4821     frp->fr_prev = after;
4822 }
4823 
4824 /*
4825  * Insert frame "frp" in a frame list before frame "before".
4826  */
4827     static void
4828 frame_insert(frame_T *before, frame_T *frp)
4829 {
4830     frp->fr_next = before;
4831     frp->fr_prev = before->fr_prev;
4832     before->fr_prev = frp;
4833     if (frp->fr_prev != NULL)
4834 	frp->fr_prev->fr_next = frp;
4835     else
4836 	frp->fr_parent->fr_child = frp;
4837 }
4838 
4839 /*
4840  * Remove a frame from a frame list.
4841  */
4842     static void
4843 frame_remove(frame_T *frp)
4844 {
4845     if (frp->fr_prev != NULL)
4846 	frp->fr_prev->fr_next = frp->fr_next;
4847     else
4848 	frp->fr_parent->fr_child = frp->fr_next;
4849     if (frp->fr_next != NULL)
4850 	frp->fr_next->fr_prev = frp->fr_prev;
4851 }
4852 
4853 #endif /* FEAT_WINDOWS */
4854 
4855 /*
4856  * Allocate w_lines[] for window "wp".
4857  * Return FAIL for failure, OK for success.
4858  */
4859     int
4860 win_alloc_lines(win_T *wp)
4861 {
4862     wp->w_lines_valid = 0;
4863     wp->w_lines = (wline_T *)alloc_clear((unsigned)(Rows * sizeof(wline_T)));
4864     if (wp->w_lines == NULL)
4865 	return FAIL;
4866     return OK;
4867 }
4868 
4869 /*
4870  * free lsize arrays for a window
4871  */
4872     void
4873 win_free_lsize(win_T *wp)
4874 {
4875     /* TODO: why would wp be NULL here? */
4876     if (wp != NULL)
4877     {
4878 	vim_free(wp->w_lines);
4879 	wp->w_lines = NULL;
4880     }
4881 }
4882 
4883 /*
4884  * Called from win_new_shellsize() after Rows changed.
4885  * This only does the current tab page, others must be done when made active.
4886  */
4887     void
4888 shell_new_rows(void)
4889 {
4890     int		h = (int)ROWS_AVAIL;
4891 
4892     if (firstwin == NULL)	/* not initialized yet */
4893 	return;
4894 #ifdef FEAT_WINDOWS
4895     if (h < frame_minheight(topframe, NULL))
4896 	h = frame_minheight(topframe, NULL);
4897 
4898     /* First try setting the heights of windows with 'winfixheight'.  If
4899      * that doesn't result in the right height, forget about that option. */
4900     frame_new_height(topframe, h, FALSE, TRUE);
4901     if (!frame_check_height(topframe, h))
4902 	frame_new_height(topframe, h, FALSE, FALSE);
4903 
4904     (void)win_comp_pos();		/* recompute w_winrow and w_wincol */
4905 #else
4906     if (h < 1)
4907 	h = 1;
4908     win_new_height(firstwin, h);
4909 #endif
4910     compute_cmdrow();
4911 #ifdef FEAT_WINDOWS
4912     curtab->tp_ch_used = p_ch;
4913 #endif
4914 
4915 #if 0
4916     /* Disabled: don't want making the screen smaller make a window larger. */
4917     if (p_ea)
4918 	win_equal(curwin, FALSE, 'v');
4919 #endif
4920 }
4921 
4922 #if defined(FEAT_WINDOWS) || defined(PROTO)
4923 /*
4924  * Called from win_new_shellsize() after Columns changed.
4925  */
4926     void
4927 shell_new_columns(void)
4928 {
4929     if (firstwin == NULL)	/* not initialized yet */
4930 	return;
4931 
4932     /* First try setting the widths of windows with 'winfixwidth'.  If that
4933      * doesn't result in the right width, forget about that option. */
4934     frame_new_width(topframe, (int)Columns, FALSE, TRUE);
4935     if (!frame_check_width(topframe, Columns))
4936 	frame_new_width(topframe, (int)Columns, FALSE, FALSE);
4937 
4938     (void)win_comp_pos();		/* recompute w_winrow and w_wincol */
4939 #if 0
4940     /* Disabled: don't want making the screen smaller make a window larger. */
4941     if (p_ea)
4942 	win_equal(curwin, FALSE, 'h');
4943 #endif
4944 }
4945 #endif
4946 
4947 #if defined(FEAT_CMDWIN) || defined(PROTO)
4948 /*
4949  * Save the size of all windows in "gap".
4950  */
4951     void
4952 win_size_save(garray_T *gap)
4953 
4954 {
4955     win_T	*wp;
4956 
4957     ga_init2(gap, (int)sizeof(int), 1);
4958     if (ga_grow(gap, win_count() * 2) == OK)
4959 	FOR_ALL_WINDOWS(wp)
4960 	{
4961 	    ((int *)gap->ga_data)[gap->ga_len++] =
4962 					       wp->w_width + wp->w_vsep_width;
4963 	    ((int *)gap->ga_data)[gap->ga_len++] = wp->w_height;
4964 	}
4965 }
4966 
4967 /*
4968  * Restore window sizes, but only if the number of windows is still the same.
4969  * Does not free the growarray.
4970  */
4971     void
4972 win_size_restore(garray_T *gap)
4973 {
4974     win_T	*wp;
4975     int		i, j;
4976 
4977     if (win_count() * 2 == gap->ga_len)
4978     {
4979 	/* The order matters, because frames contain other frames, but it's
4980 	 * difficult to get right. The easy way out is to do it twice. */
4981 	for (j = 0; j < 2; ++j)
4982 	{
4983 	    i = 0;
4984 	    FOR_ALL_WINDOWS(wp)
4985 	    {
4986 		frame_setwidth(wp->w_frame, ((int *)gap->ga_data)[i++]);
4987 		win_setheight_win(((int *)gap->ga_data)[i++], wp);
4988 	    }
4989 	}
4990 	/* recompute the window positions */
4991 	(void)win_comp_pos();
4992     }
4993 }
4994 #endif /* FEAT_CMDWIN */
4995 
4996 #if defined(FEAT_WINDOWS) || defined(PROTO)
4997 /*
4998  * Update the position for all windows, using the width and height of the
4999  * frames.
5000  * Returns the row just after the last window.
5001  */
5002     int
5003 win_comp_pos(void)
5004 {
5005     int		row = tabline_height();
5006     int		col = 0;
5007 
5008     frame_comp_pos(topframe, &row, &col);
5009     return row;
5010 }
5011 
5012 /*
5013  * Update the position of the windows in frame "topfrp", using the width and
5014  * height of the frames.
5015  * "*row" and "*col" are the top-left position of the frame.  They are updated
5016  * to the bottom-right position plus one.
5017  */
5018     static void
5019 frame_comp_pos(frame_T *topfrp, int *row, int *col)
5020 {
5021     win_T	*wp;
5022     frame_T	*frp;
5023     int		startcol;
5024     int		startrow;
5025 
5026     wp = topfrp->fr_win;
5027     if (wp != NULL)
5028     {
5029 	if (wp->w_winrow != *row || wp->w_wincol != *col)
5030 	{
5031 	    /* position changed, redraw */
5032 	    wp->w_winrow = *row;
5033 	    wp->w_wincol = *col;
5034 	    redraw_win_later(wp, NOT_VALID);
5035 	    wp->w_redr_status = TRUE;
5036 	}
5037 	*row += wp->w_height + wp->w_status_height;
5038 	*col += wp->w_width + wp->w_vsep_width;
5039     }
5040     else
5041     {
5042 	startrow = *row;
5043 	startcol = *col;
5044 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
5045 	{
5046 	    if (topfrp->fr_layout == FR_ROW)
5047 		*row = startrow;	/* all frames are at the same row */
5048 	    else
5049 		*col = startcol;	/* all frames are at the same col */
5050 	    frame_comp_pos(frp, row, col);
5051 	}
5052     }
5053 }
5054 
5055 #endif /* FEAT_WINDOWS */
5056 
5057 /*
5058  * Set current window height and take care of repositioning other windows to
5059  * fit around it.
5060  */
5061     void
5062 win_setheight(int height)
5063 {
5064     win_setheight_win(height, curwin);
5065 }
5066 
5067 /*
5068  * Set the window height of window "win" and take care of repositioning other
5069  * windows to fit around it.
5070  */
5071     void
5072 win_setheight_win(int height, win_T *win)
5073 {
5074     int		row;
5075 
5076     if (win == curwin)
5077     {
5078 	/* Always keep current window at least one line high, even when
5079 	 * 'winminheight' is zero. */
5080 #ifdef FEAT_WINDOWS
5081 	if (height < p_wmh)
5082 	    height = p_wmh;
5083 #endif
5084 	if (height == 0)
5085 	    height = 1;
5086     }
5087 
5088 #ifdef FEAT_WINDOWS
5089     frame_setheight(win->w_frame, height + win->w_status_height);
5090 
5091     /* recompute the window positions */
5092     row = win_comp_pos();
5093 #else
5094     if (height > topframe->fr_height)
5095 	height = topframe->fr_height;
5096     win->w_height = height;
5097     row = height;
5098 #endif
5099 
5100     /*
5101      * If there is extra space created between the last window and the command
5102      * line, clear it.
5103      */
5104     if (full_screen && msg_scrolled == 0 && row < cmdline_row)
5105 	screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5106     cmdline_row = row;
5107     msg_row = row;
5108     msg_col = 0;
5109 
5110     redraw_all_later(NOT_VALID);
5111 }
5112 
5113 #if defined(FEAT_WINDOWS) || defined(PROTO)
5114 
5115 /*
5116  * Set the height of a frame to "height" and take care that all frames and
5117  * windows inside it are resized.  Also resize frames on the left and right if
5118  * the are in the same FR_ROW frame.
5119  *
5120  * Strategy:
5121  * If the frame is part of a FR_COL frame, try fitting the frame in that
5122  * frame.  If that doesn't work (the FR_COL frame is too small), recursively
5123  * go to containing frames to resize them and make room.
5124  * If the frame is part of a FR_ROW frame, all frames must be resized as well.
5125  * Check for the minimal height of the FR_ROW frame.
5126  * At the top level we can also use change the command line height.
5127  */
5128     static void
5129 frame_setheight(frame_T *curfrp, int height)
5130 {
5131     int		room;		/* total number of lines available */
5132     int		take;		/* number of lines taken from other windows */
5133     int		room_cmdline;	/* lines available from cmdline */
5134     int		run;
5135     frame_T	*frp;
5136     int		h;
5137     int		room_reserved;
5138 
5139     /* If the height already is the desired value, nothing to do. */
5140     if (curfrp->fr_height == height)
5141 	return;
5142 
5143     if (curfrp->fr_parent == NULL)
5144     {
5145 	/* topframe: can only change the command line */
5146 	if (height > ROWS_AVAIL)
5147 	    height = ROWS_AVAIL;
5148 	if (height > 0)
5149 	    frame_new_height(curfrp, height, FALSE, FALSE);
5150     }
5151     else if (curfrp->fr_parent->fr_layout == FR_ROW)
5152     {
5153 	/* Row of frames: Also need to resize frames left and right of this
5154 	 * one.  First check for the minimal height of these. */
5155 	h = frame_minheight(curfrp->fr_parent, NULL);
5156 	if (height < h)
5157 	    height = h;
5158 	frame_setheight(curfrp->fr_parent, height);
5159     }
5160     else
5161     {
5162 	/*
5163 	 * Column of frames: try to change only frames in this column.
5164 	 */
5165 	/*
5166 	 * Do this twice:
5167 	 * 1: compute room available, if it's not enough try resizing the
5168 	 *    containing frame.
5169 	 * 2: compute the room available and adjust the height to it.
5170 	 * Try not to reduce the height of a window with 'winfixheight' set.
5171 	 */
5172 	for (run = 1; run <= 2; ++run)
5173 	{
5174 	    room = 0;
5175 	    room_reserved = 0;
5176 	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
5177 							   frp = frp->fr_next)
5178 	    {
5179 		if (frp != curfrp
5180 			&& frp->fr_win != NULL
5181 			&& frp->fr_win->w_p_wfh)
5182 		    room_reserved += frp->fr_height;
5183 		room += frp->fr_height;
5184 		if (frp != curfrp)
5185 		    room -= frame_minheight(frp, NULL);
5186 	    }
5187 	    if (curfrp->fr_width != Columns)
5188 		room_cmdline = 0;
5189 	    else
5190 	    {
5191 		room_cmdline = Rows - p_ch - (lastwin->w_winrow
5192 			       + lastwin->w_height + lastwin->w_status_height);
5193 		if (room_cmdline < 0)
5194 		    room_cmdline = 0;
5195 	    }
5196 
5197 	    if (height <= room + room_cmdline)
5198 		break;
5199 	    if (run == 2 || curfrp->fr_width == Columns)
5200 	    {
5201 		if (height > room + room_cmdline)
5202 		    height = room + room_cmdline;
5203 		break;
5204 	    }
5205 	    frame_setheight(curfrp->fr_parent, height
5206 		+ frame_minheight(curfrp->fr_parent, NOWIN) - (int)p_wmh - 1);
5207 	}
5208 
5209 	/*
5210 	 * Compute the number of lines we will take from others frames (can be
5211 	 * negative!).
5212 	 */
5213 	take = height - curfrp->fr_height;
5214 
5215 	/* If there is not enough room, also reduce the height of a window
5216 	 * with 'winfixheight' set. */
5217 	if (height > room + room_cmdline - room_reserved)
5218 	    room_reserved = room + room_cmdline - height;
5219 	/* If there is only a 'winfixheight' window and making the
5220 	 * window smaller, need to make the other window taller. */
5221 	if (take < 0 && room - curfrp->fr_height < room_reserved)
5222 	    room_reserved = 0;
5223 
5224 	if (take > 0 && room_cmdline > 0)
5225 	{
5226 	    /* use lines from cmdline first */
5227 	    if (take < room_cmdline)
5228 		room_cmdline = take;
5229 	    take -= room_cmdline;
5230 	    topframe->fr_height += room_cmdline;
5231 	}
5232 
5233 	/*
5234 	 * set the current frame to the new height
5235 	 */
5236 	frame_new_height(curfrp, height, FALSE, FALSE);
5237 
5238 	/*
5239 	 * First take lines from the frames after the current frame.  If
5240 	 * that is not enough, takes lines from frames above the current
5241 	 * frame.
5242 	 */
5243 	for (run = 0; run < 2; ++run)
5244 	{
5245 	    if (run == 0)
5246 		frp = curfrp->fr_next;	/* 1st run: start with next window */
5247 	    else
5248 		frp = curfrp->fr_prev;	/* 2nd run: start with prev window */
5249 	    while (frp != NULL && take != 0)
5250 	    {
5251 		h = frame_minheight(frp, NULL);
5252 		if (room_reserved > 0
5253 			&& frp->fr_win != NULL
5254 			&& frp->fr_win->w_p_wfh)
5255 		{
5256 		    if (room_reserved >= frp->fr_height)
5257 			room_reserved -= frp->fr_height;
5258 		    else
5259 		    {
5260 			if (frp->fr_height - room_reserved > take)
5261 			    room_reserved = frp->fr_height - take;
5262 			take -= frp->fr_height - room_reserved;
5263 			frame_new_height(frp, room_reserved, FALSE, FALSE);
5264 			room_reserved = 0;
5265 		    }
5266 		}
5267 		else
5268 		{
5269 		    if (frp->fr_height - take < h)
5270 		    {
5271 			take -= frp->fr_height - h;
5272 			frame_new_height(frp, h, FALSE, FALSE);
5273 		    }
5274 		    else
5275 		    {
5276 			frame_new_height(frp, frp->fr_height - take,
5277 								FALSE, FALSE);
5278 			take = 0;
5279 		    }
5280 		}
5281 		if (run == 0)
5282 		    frp = frp->fr_next;
5283 		else
5284 		    frp = frp->fr_prev;
5285 	    }
5286 	}
5287     }
5288 }
5289 
5290 /*
5291  * Set current window width and take care of repositioning other windows to
5292  * fit around it.
5293  */
5294     void
5295 win_setwidth(int width)
5296 {
5297     win_setwidth_win(width, curwin);
5298 }
5299 
5300     void
5301 win_setwidth_win(int width, win_T *wp)
5302 {
5303     /* Always keep current window at least one column wide, even when
5304      * 'winminwidth' is zero. */
5305     if (wp == curwin)
5306     {
5307 	if (width < p_wmw)
5308 	    width = p_wmw;
5309 	if (width == 0)
5310 	    width = 1;
5311     }
5312 
5313     frame_setwidth(wp->w_frame, width + wp->w_vsep_width);
5314 
5315     /* recompute the window positions */
5316     (void)win_comp_pos();
5317 
5318     redraw_all_later(NOT_VALID);
5319 }
5320 
5321 /*
5322  * Set the width of a frame to "width" and take care that all frames and
5323  * windows inside it are resized.  Also resize frames above and below if the
5324  * are in the same FR_ROW frame.
5325  *
5326  * Strategy is similar to frame_setheight().
5327  */
5328     static void
5329 frame_setwidth(frame_T *curfrp, int width)
5330 {
5331     int		room;		/* total number of lines available */
5332     int		take;		/* number of lines taken from other windows */
5333     int		run;
5334     frame_T	*frp;
5335     int		w;
5336     int		room_reserved;
5337 
5338     /* If the width already is the desired value, nothing to do. */
5339     if (curfrp->fr_width == width)
5340 	return;
5341 
5342     if (curfrp->fr_parent == NULL)
5343 	/* topframe: can't change width */
5344 	return;
5345 
5346     if (curfrp->fr_parent->fr_layout == FR_COL)
5347     {
5348 	/* Column of frames: Also need to resize frames above and below of
5349 	 * this one.  First check for the minimal width of these. */
5350 	w = frame_minwidth(curfrp->fr_parent, NULL);
5351 	if (width < w)
5352 	    width = w;
5353 	frame_setwidth(curfrp->fr_parent, width);
5354     }
5355     else
5356     {
5357 	/*
5358 	 * Row of frames: try to change only frames in this row.
5359 	 *
5360 	 * Do this twice:
5361 	 * 1: compute room available, if it's not enough try resizing the
5362 	 *    containing frame.
5363 	 * 2: compute the room available and adjust the width to it.
5364 	 */
5365 	for (run = 1; run <= 2; ++run)
5366 	{
5367 	    room = 0;
5368 	    room_reserved = 0;
5369 	    for (frp = curfrp->fr_parent->fr_child; frp != NULL;
5370 							   frp = frp->fr_next)
5371 	    {
5372 		if (frp != curfrp
5373 			&& frp->fr_win != NULL
5374 			&& frp->fr_win->w_p_wfw)
5375 		    room_reserved += frp->fr_width;
5376 		room += frp->fr_width;
5377 		if (frp != curfrp)
5378 		    room -= frame_minwidth(frp, NULL);
5379 	    }
5380 
5381 	    if (width <= room)
5382 		break;
5383 	    if (run == 2 || curfrp->fr_height >= ROWS_AVAIL)
5384 	    {
5385 		if (width > room)
5386 		    width = room;
5387 		break;
5388 	    }
5389 	    frame_setwidth(curfrp->fr_parent, width
5390 		 + frame_minwidth(curfrp->fr_parent, NOWIN) - (int)p_wmw - 1);
5391 	}
5392 
5393 	/*
5394 	 * Compute the number of lines we will take from others frames (can be
5395 	 * negative!).
5396 	 */
5397 	take = width - curfrp->fr_width;
5398 
5399 	/* If there is not enough room, also reduce the width of a window
5400 	 * with 'winfixwidth' set. */
5401 	if (width > room - room_reserved)
5402 	    room_reserved = room - width;
5403 	/* If there is only a 'winfixwidth' window and making the
5404 	 * window smaller, need to make the other window narrower. */
5405 	if (take < 0 && room - curfrp->fr_width < room_reserved)
5406 	    room_reserved = 0;
5407 
5408 	/*
5409 	 * set the current frame to the new width
5410 	 */
5411 	frame_new_width(curfrp, width, FALSE, FALSE);
5412 
5413 	/*
5414 	 * First take lines from the frames right of the current frame.  If
5415 	 * that is not enough, takes lines from frames left of the current
5416 	 * frame.
5417 	 */
5418 	for (run = 0; run < 2; ++run)
5419 	{
5420 	    if (run == 0)
5421 		frp = curfrp->fr_next;	/* 1st run: start with next window */
5422 	    else
5423 		frp = curfrp->fr_prev;	/* 2nd run: start with prev window */
5424 	    while (frp != NULL && take != 0)
5425 	    {
5426 		w = frame_minwidth(frp, NULL);
5427 		if (room_reserved > 0
5428 			&& frp->fr_win != NULL
5429 			&& frp->fr_win->w_p_wfw)
5430 		{
5431 		    if (room_reserved >= frp->fr_width)
5432 			room_reserved -= frp->fr_width;
5433 		    else
5434 		    {
5435 			if (frp->fr_width - room_reserved > take)
5436 			    room_reserved = frp->fr_width - take;
5437 			take -= frp->fr_width - room_reserved;
5438 			frame_new_width(frp, room_reserved, FALSE, FALSE);
5439 			room_reserved = 0;
5440 		    }
5441 		}
5442 		else
5443 		{
5444 		    if (frp->fr_width - take < w)
5445 		    {
5446 			take -= frp->fr_width - w;
5447 			frame_new_width(frp, w, FALSE, FALSE);
5448 		    }
5449 		    else
5450 		    {
5451 			frame_new_width(frp, frp->fr_width - take,
5452 								FALSE, FALSE);
5453 			take = 0;
5454 		    }
5455 		}
5456 		if (run == 0)
5457 		    frp = frp->fr_next;
5458 		else
5459 		    frp = frp->fr_prev;
5460 	    }
5461 	}
5462     }
5463 }
5464 
5465 /*
5466  * Check 'winminheight' for a valid value.
5467  */
5468     void
5469 win_setminheight(void)
5470 {
5471     int		room;
5472     int		first = TRUE;
5473     win_T	*wp;
5474 
5475     /* loop until there is a 'winminheight' that is possible */
5476     while (p_wmh > 0)
5477     {
5478 	/* TODO: handle vertical splits */
5479 	room = -p_wh;
5480 	FOR_ALL_WINDOWS(wp)
5481 	    room += wp->w_height - p_wmh;
5482 	if (room >= 0)
5483 	    break;
5484 	--p_wmh;
5485 	if (first)
5486 	{
5487 	    EMSG(_(e_noroom));
5488 	    first = FALSE;
5489 	}
5490     }
5491 }
5492 
5493 #if defined(FEAT_MOUSE) || defined(PROTO)
5494 
5495 /*
5496  * Status line of dragwin is dragged "offset" lines down (negative is up).
5497  */
5498     void
5499 win_drag_status_line(win_T *dragwin, int offset)
5500 {
5501     frame_T	*curfr;
5502     frame_T	*fr;
5503     int		room;
5504     int		row;
5505     int		up;	/* if TRUE, drag status line up, otherwise down */
5506     int		n;
5507 
5508     fr = dragwin->w_frame;
5509     curfr = fr;
5510     if (fr != topframe)		/* more than one window */
5511     {
5512 	fr = fr->fr_parent;
5513 	/* When the parent frame is not a column of frames, its parent should
5514 	 * be. */
5515 	if (fr->fr_layout != FR_COL)
5516 	{
5517 	    curfr = fr;
5518 	    if (fr != topframe)	/* only a row of windows, may drag statusline */
5519 		fr = fr->fr_parent;
5520 	}
5521     }
5522 
5523     /* If this is the last frame in a column, may want to resize the parent
5524      * frame instead (go two up to skip a row of frames). */
5525     while (curfr != topframe && curfr->fr_next == NULL)
5526     {
5527 	if (fr != topframe)
5528 	    fr = fr->fr_parent;
5529 	curfr = fr;
5530 	if (fr != topframe)
5531 	    fr = fr->fr_parent;
5532     }
5533 
5534     if (offset < 0) /* drag up */
5535     {
5536 	up = TRUE;
5537 	offset = -offset;
5538 	/* sum up the room of the current frame and above it */
5539 	if (fr == curfr)
5540 	{
5541 	    /* only one window */
5542 	    room = fr->fr_height - frame_minheight(fr, NULL);
5543 	}
5544 	else
5545 	{
5546 	    room = 0;
5547 	    for (fr = fr->fr_child; ; fr = fr->fr_next)
5548 	    {
5549 		room += fr->fr_height - frame_minheight(fr, NULL);
5550 		if (fr == curfr)
5551 		    break;
5552 	    }
5553 	}
5554 	fr = curfr->fr_next;		/* put fr at frame that grows */
5555     }
5556     else    /* drag down */
5557     {
5558 	up = FALSE;
5559 	/*
5560 	 * Only dragging the last status line can reduce p_ch.
5561 	 */
5562 	room = Rows - cmdline_row;
5563 	if (curfr->fr_next == NULL)
5564 	    room -= 1;
5565 	else
5566 	    room -= p_ch;
5567 	if (room < 0)
5568 	    room = 0;
5569 	/* sum up the room of frames below of the current one */
5570 	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
5571 	    room += fr->fr_height - frame_minheight(fr, NULL);
5572 	fr = curfr;			/* put fr at window that grows */
5573     }
5574 
5575     if (room < offset)		/* Not enough room */
5576 	offset = room;		/* Move as far as we can */
5577     if (offset <= 0)
5578 	return;
5579 
5580     /*
5581      * Grow frame fr by "offset" lines.
5582      * Doesn't happen when dragging the last status line up.
5583      */
5584     if (fr != NULL)
5585 	frame_new_height(fr, fr->fr_height + offset, up, FALSE);
5586 
5587     if (up)
5588 	fr = curfr;		/* current frame gets smaller */
5589     else
5590 	fr = curfr->fr_next;	/* next frame gets smaller */
5591 
5592     /*
5593      * Now make the other frames smaller.
5594      */
5595     while (fr != NULL && offset > 0)
5596     {
5597 	n = frame_minheight(fr, NULL);
5598 	if (fr->fr_height - offset <= n)
5599 	{
5600 	    offset -= fr->fr_height - n;
5601 	    frame_new_height(fr, n, !up, FALSE);
5602 	}
5603 	else
5604 	{
5605 	    frame_new_height(fr, fr->fr_height - offset, !up, FALSE);
5606 	    break;
5607 	}
5608 	if (up)
5609 	    fr = fr->fr_prev;
5610 	else
5611 	    fr = fr->fr_next;
5612     }
5613     row = win_comp_pos();
5614     screen_fill(row, cmdline_row, 0, (int)Columns, ' ', ' ', 0);
5615     cmdline_row = row;
5616     p_ch = Rows - cmdline_row;
5617     if (p_ch < 1)
5618 	p_ch = 1;
5619     curtab->tp_ch_used = p_ch;
5620     redraw_all_later(SOME_VALID);
5621     showmode();
5622 }
5623 
5624 /*
5625  * Separator line of dragwin is dragged "offset" lines right (negative is left).
5626  */
5627     void
5628 win_drag_vsep_line(win_T *dragwin, int offset)
5629 {
5630     frame_T	*curfr;
5631     frame_T	*fr;
5632     int		room;
5633     int		left;	/* if TRUE, drag separator line left, otherwise right */
5634     int		n;
5635 
5636     fr = dragwin->w_frame;
5637     if (fr == topframe)		/* only one window (cannot happen?) */
5638 	return;
5639     curfr = fr;
5640     fr = fr->fr_parent;
5641     /* When the parent frame is not a row of frames, its parent should be. */
5642     if (fr->fr_layout != FR_ROW)
5643     {
5644 	if (fr == topframe)	/* only a column of windows (cannot happen?) */
5645 	    return;
5646 	curfr = fr;
5647 	fr = fr->fr_parent;
5648     }
5649 
5650     /* If this is the last frame in a row, may want to resize a parent
5651      * frame instead. */
5652     while (curfr->fr_next == NULL)
5653     {
5654 	if (fr == topframe)
5655 	    break;
5656 	curfr = fr;
5657 	fr = fr->fr_parent;
5658 	if (fr != topframe)
5659 	{
5660 	    curfr = fr;
5661 	    fr = fr->fr_parent;
5662 	}
5663     }
5664 
5665     if (offset < 0) /* drag left */
5666     {
5667 	left = TRUE;
5668 	offset = -offset;
5669 	/* sum up the room of the current frame and left of it */
5670 	room = 0;
5671 	for (fr = fr->fr_child; ; fr = fr->fr_next)
5672 	{
5673 	    room += fr->fr_width - frame_minwidth(fr, NULL);
5674 	    if (fr == curfr)
5675 		break;
5676 	}
5677 	fr = curfr->fr_next;		/* put fr at frame that grows */
5678     }
5679     else    /* drag right */
5680     {
5681 	left = FALSE;
5682 	/* sum up the room of frames right of the current one */
5683 	room = 0;
5684 	for (fr = curfr->fr_next; fr != NULL; fr = fr->fr_next)
5685 	    room += fr->fr_width - frame_minwidth(fr, NULL);
5686 	fr = curfr;			/* put fr at window that grows */
5687     }
5688 
5689     if (room < offset)		/* Not enough room */
5690 	offset = room;		/* Move as far as we can */
5691     if (offset <= 0)		/* No room at all, quit. */
5692 	return;
5693     if (fr == NULL)
5694 	return;			/* Safety check, should not happen. */
5695 
5696     /* grow frame fr by offset lines */
5697     frame_new_width(fr, fr->fr_width + offset, left, FALSE);
5698 
5699     /* shrink other frames: current and at the left or at the right */
5700     if (left)
5701 	fr = curfr;		/* current frame gets smaller */
5702     else
5703 	fr = curfr->fr_next;	/* next frame gets smaller */
5704 
5705     while (fr != NULL && offset > 0)
5706     {
5707 	n = frame_minwidth(fr, NULL);
5708 	if (fr->fr_width - offset <= n)
5709 	{
5710 	    offset -= fr->fr_width - n;
5711 	    frame_new_width(fr, n, !left, FALSE);
5712 	}
5713 	else
5714 	{
5715 	    frame_new_width(fr, fr->fr_width - offset, !left, FALSE);
5716 	    break;
5717 	}
5718 	if (left)
5719 	    fr = fr->fr_prev;
5720 	else
5721 	    fr = fr->fr_next;
5722     }
5723     (void)win_comp_pos();
5724     redraw_all_later(NOT_VALID);
5725 }
5726 #endif /* FEAT_MOUSE */
5727 
5728 #endif /* FEAT_WINDOWS */
5729 
5730 #define FRACTION_MULT	16384L
5731 
5732 /*
5733  * Set wp->w_fraction for the current w_wrow and w_height.
5734  */
5735     void
5736 set_fraction(win_T *wp)
5737 {
5738     wp->w_fraction = ((long)wp->w_wrow * FRACTION_MULT
5739 				    + wp->w_height / 2) / (long)wp->w_height;
5740 }
5741 
5742 /*
5743  * Set the height of a window.
5744  * This takes care of the things inside the window, not what happens to the
5745  * window position, the frame or to other windows.
5746  */
5747     void
5748 win_new_height(win_T *wp, int height)
5749 {
5750     int		prev_height = wp->w_height;
5751 
5752     /* Don't want a negative height.  Happens when splitting a tiny window.
5753      * Will equalize heights soon to fix it. */
5754     if (height < 0)
5755 	height = 0;
5756     if (wp->w_height == height)
5757 	return;	    /* nothing to do */
5758 
5759     if (wp->w_height > 0)
5760     {
5761 	if (wp == curwin)
5762 	    /* w_wrow needs to be valid. When setting 'laststatus' this may
5763 	     * call win_new_height() recursively. */
5764 	    validate_cursor();
5765 	if (wp->w_height != prev_height)
5766 	    return;  /* Recursive call already changed the size, bail out here
5767 			to avoid the following to mess things up. */
5768 	if (wp->w_wrow != wp->w_prev_fraction_row)
5769 	    set_fraction(wp);
5770     }
5771 
5772     wp->w_height = height;
5773     wp->w_skipcol = 0;
5774 
5775     /* There is no point in adjusting the scroll position when exiting.  Some
5776      * values might be invalid. */
5777     if (!exiting)
5778 	scroll_to_fraction(wp, prev_height);
5779 }
5780 
5781     void
5782 scroll_to_fraction(win_T *wp, int prev_height)
5783 {
5784     linenr_T	lnum;
5785     int		sline, line_size;
5786     int		height = wp->w_height;
5787 
5788     /* Don't change w_topline when height is zero.  Don't set w_topline when
5789      * 'scrollbind' is set and this isn't the current window. */
5790     if (height > 0
5791 #ifdef FEAT_SCROLLBIND
5792 	    && (!wp->w_p_scb || wp == curwin)
5793 #endif
5794        )
5795     {
5796 	/*
5797 	 * Find a value for w_topline that shows the cursor at the same
5798 	 * relative position in the window as before (more or less).
5799 	 */
5800 	lnum = wp->w_cursor.lnum;
5801 	if (lnum < 1)		/* can happen when starting up */
5802 	    lnum = 1;
5803 	wp->w_wrow = ((long)wp->w_fraction * (long)height - 1L
5804 					 + FRACTION_MULT / 2) / FRACTION_MULT;
5805 	line_size = plines_win_col(wp, lnum, (long)(wp->w_cursor.col)) - 1;
5806 	sline = wp->w_wrow - line_size;
5807 
5808 	if (sline >= 0)
5809 	{
5810 	    /* Make sure the whole cursor line is visible, if possible. */
5811 	    int rows = plines_win(wp, lnum, FALSE);
5812 
5813 	    if (sline > wp->w_height - rows)
5814 	    {
5815 		sline = wp->w_height - rows;
5816 		wp->w_wrow -= rows - line_size;
5817 	    }
5818 	}
5819 
5820 	if (sline < 0)
5821 	{
5822 	    /*
5823 	     * Cursor line would go off top of screen if w_wrow was this high.
5824 	     * Make cursor line the first line in the window.  If not enough
5825 	     * room use w_skipcol;
5826 	     */
5827 	    wp->w_wrow = line_size;
5828 	    if (wp->w_wrow >= wp->w_height
5829 				       && (W_WIDTH(wp) - win_col_off(wp)) > 0)
5830 	    {
5831 		wp->w_skipcol += W_WIDTH(wp) - win_col_off(wp);
5832 		--wp->w_wrow;
5833 		while (wp->w_wrow >= wp->w_height)
5834 		{
5835 		    wp->w_skipcol += W_WIDTH(wp) - win_col_off(wp)
5836 							   + win_col_off2(wp);
5837 		    --wp->w_wrow;
5838 		}
5839 	    }
5840 	    set_topline(wp, lnum);
5841 	}
5842 	else if (sline > 0)
5843 	{
5844 	    while (sline > 0 && lnum > 1)
5845 	    {
5846 #ifdef FEAT_FOLDING
5847 		hasFoldingWin(wp, lnum, &lnum, NULL, TRUE, NULL);
5848 		if (lnum == 1)
5849 		{
5850 		    /* first line in buffer is folded */
5851 		    line_size = 1;
5852 		    --sline;
5853 		    break;
5854 		}
5855 #endif
5856 		--lnum;
5857 #ifdef FEAT_DIFF
5858 		if (lnum == wp->w_topline)
5859 		    line_size = plines_win_nofill(wp, lnum, TRUE)
5860 							      + wp->w_topfill;
5861 		else
5862 #endif
5863 		    line_size = plines_win(wp, lnum, TRUE);
5864 		sline -= line_size;
5865 	    }
5866 
5867 	    if (sline < 0)
5868 	    {
5869 		/*
5870 		 * Line we want at top would go off top of screen.  Use next
5871 		 * line instead.
5872 		 */
5873 #ifdef FEAT_FOLDING
5874 		hasFoldingWin(wp, lnum, NULL, &lnum, TRUE, NULL);
5875 #endif
5876 		lnum++;
5877 		wp->w_wrow -= line_size + sline;
5878 	    }
5879 	    else if (sline > 0)
5880 	    {
5881 		/* First line of file reached, use that as topline. */
5882 		lnum = 1;
5883 		wp->w_wrow -= sline;
5884 	    }
5885 
5886 	    set_topline(wp, lnum);
5887 	}
5888     }
5889 
5890     if (wp == curwin)
5891     {
5892 	if (p_so)
5893 	    update_topline();
5894 	curs_columns(FALSE);	/* validate w_wrow */
5895     }
5896     if (prev_height > 0)
5897 	wp->w_prev_fraction_row = wp->w_wrow;
5898 
5899     win_comp_scroll(wp);
5900     redraw_win_later(wp, SOME_VALID);
5901 #ifdef FEAT_WINDOWS
5902     wp->w_redr_status = TRUE;
5903 #endif
5904     invalidate_botline_win(wp);
5905 }
5906 
5907 #ifdef FEAT_WINDOWS
5908 /*
5909  * Set the width of a window.
5910  */
5911     void
5912 win_new_width(win_T *wp, int width)
5913 {
5914     wp->w_width = width;
5915     wp->w_lines_valid = 0;
5916     changed_line_abv_curs_win(wp);
5917     invalidate_botline_win(wp);
5918     if (wp == curwin)
5919     {
5920 	update_topline();
5921 	curs_columns(TRUE);	/* validate w_wrow */
5922     }
5923     redraw_win_later(wp, NOT_VALID);
5924     wp->w_redr_status = TRUE;
5925 }
5926 #endif
5927 
5928     void
5929 win_comp_scroll(win_T *wp)
5930 {
5931     wp->w_p_scr = ((unsigned)wp->w_height >> 1);
5932     if (wp->w_p_scr == 0)
5933 	wp->w_p_scr = 1;
5934 }
5935 
5936 /*
5937  * command_height: called whenever p_ch has been changed
5938  */
5939     void
5940 command_height(void)
5941 {
5942 #ifdef FEAT_WINDOWS
5943     int		h;
5944     frame_T	*frp;
5945     int		old_p_ch = curtab->tp_ch_used;
5946 
5947     /* Use the value of p_ch that we remembered.  This is needed for when the
5948      * GUI starts up, we can't be sure in what order things happen.  And when
5949      * p_ch was changed in another tab page. */
5950     curtab->tp_ch_used = p_ch;
5951 
5952     /* Find bottom frame with width of screen. */
5953     frp = lastwin->w_frame;
5954     while (frp->fr_width != Columns && frp->fr_parent != NULL)
5955 	frp = frp->fr_parent;
5956 
5957     /* Avoid changing the height of a window with 'winfixheight' set. */
5958     while (frp->fr_prev != NULL && frp->fr_layout == FR_LEAF
5959 						      && frp->fr_win->w_p_wfh)
5960 	frp = frp->fr_prev;
5961 
5962     if (starting != NO_SCREEN)
5963     {
5964 	cmdline_row = Rows - p_ch;
5965 
5966 	if (p_ch > old_p_ch)		    /* p_ch got bigger */
5967 	{
5968 	    while (p_ch > old_p_ch)
5969 	    {
5970 		if (frp == NULL)
5971 		{
5972 		    EMSG(_(e_noroom));
5973 		    p_ch = old_p_ch;
5974 		    curtab->tp_ch_used = p_ch;
5975 		    cmdline_row = Rows - p_ch;
5976 		    break;
5977 		}
5978 		h = frp->fr_height - frame_minheight(frp, NULL);
5979 		if (h > p_ch - old_p_ch)
5980 		    h = p_ch - old_p_ch;
5981 		old_p_ch += h;
5982 		frame_add_height(frp, -h);
5983 		frp = frp->fr_prev;
5984 	    }
5985 
5986 	    /* Recompute window positions. */
5987 	    (void)win_comp_pos();
5988 
5989 	    /* clear the lines added to cmdline */
5990 	    if (full_screen)
5991 		screen_fill((int)(cmdline_row), (int)Rows, 0,
5992 						   (int)Columns, ' ', ' ', 0);
5993 	    msg_row = cmdline_row;
5994 	    redraw_cmdline = TRUE;
5995 	    return;
5996 	}
5997 
5998 	if (msg_row < cmdline_row)
5999 	    msg_row = cmdline_row;
6000 	redraw_cmdline = TRUE;
6001     }
6002     frame_add_height(frp, (int)(old_p_ch - p_ch));
6003 
6004     /* Recompute window positions. */
6005     if (frp != lastwin->w_frame)
6006 	(void)win_comp_pos();
6007 #else
6008     cmdline_row = Rows - p_ch;
6009     win_setheight(cmdline_row);
6010 #endif
6011 }
6012 
6013 #if defined(FEAT_WINDOWS) || defined(PROTO)
6014 /*
6015  * Resize frame "frp" to be "n" lines higher (negative for less high).
6016  * Also resize the frames it is contained in.
6017  */
6018     static void
6019 frame_add_height(frame_T *frp, int n)
6020 {
6021     frame_new_height(frp, frp->fr_height + n, FALSE, FALSE);
6022     for (;;)
6023     {
6024 	frp = frp->fr_parent;
6025 	if (frp == NULL)
6026 	    break;
6027 	frp->fr_height += n;
6028     }
6029 }
6030 
6031 /*
6032  * Add or remove a status line for the bottom window(s), according to the
6033  * value of 'laststatus'.
6034  */
6035     void
6036 last_status(
6037     int		morewin)	/* pretend there are two or more windows */
6038 {
6039     /* Don't make a difference between horizontal or vertical split. */
6040     last_status_rec(topframe, (p_ls == 2
6041 			  || (p_ls == 1 && (morewin || !ONE_WINDOW))));
6042 }
6043 
6044     static void
6045 last_status_rec(frame_T *fr, int statusline)
6046 {
6047     frame_T	*fp;
6048     win_T	*wp;
6049 
6050     if (fr->fr_layout == FR_LEAF)
6051     {
6052 	wp = fr->fr_win;
6053 	if (wp->w_status_height != 0 && !statusline)
6054 	{
6055 	    /* remove status line */
6056 	    win_new_height(wp, wp->w_height + 1);
6057 	    wp->w_status_height = 0;
6058 	    comp_col();
6059 	}
6060 	else if (wp->w_status_height == 0 && statusline)
6061 	{
6062 	    /* Find a frame to take a line from. */
6063 	    fp = fr;
6064 	    while (fp->fr_height <= frame_minheight(fp, NULL))
6065 	    {
6066 		if (fp == topframe)
6067 		{
6068 		    EMSG(_(e_noroom));
6069 		    return;
6070 		}
6071 		/* In a column of frames: go to frame above.  If already at
6072 		 * the top or in a row of frames: go to parent. */
6073 		if (fp->fr_parent->fr_layout == FR_COL && fp->fr_prev != NULL)
6074 		    fp = fp->fr_prev;
6075 		else
6076 		    fp = fp->fr_parent;
6077 	    }
6078 	    wp->w_status_height = 1;
6079 	    if (fp != fr)
6080 	    {
6081 		frame_new_height(fp, fp->fr_height - 1, FALSE, FALSE);
6082 		frame_fix_height(wp);
6083 		(void)win_comp_pos();
6084 	    }
6085 	    else
6086 		win_new_height(wp, wp->w_height - 1);
6087 	    comp_col();
6088 	    redraw_all_later(SOME_VALID);
6089 	}
6090     }
6091     else if (fr->fr_layout == FR_ROW)
6092     {
6093 	/* vertically split windows, set status line for each one */
6094 	for (fp = fr->fr_child; fp != NULL; fp = fp->fr_next)
6095 	    last_status_rec(fp, statusline);
6096     }
6097     else
6098     {
6099 	/* horizontally split window, set status line for last one */
6100 	for (fp = fr->fr_child; fp->fr_next != NULL; fp = fp->fr_next)
6101 	    ;
6102 	last_status_rec(fp, statusline);
6103     }
6104 }
6105 
6106 /*
6107  * Return the number of lines used by the tab page line.
6108  */
6109     int
6110 tabline_height(void)
6111 {
6112 #ifdef FEAT_GUI_TABLINE
6113     /* When the GUI has the tabline then this always returns zero. */
6114     if (gui_use_tabline())
6115 	return 0;
6116 #endif
6117     switch (p_stal)
6118     {
6119 	case 0: return 0;
6120 	case 1: return (first_tabpage->tp_next == NULL) ? 0 : 1;
6121     }
6122     return 1;
6123 }
6124 
6125 #endif /* FEAT_WINDOWS */
6126 
6127 #if defined(FEAT_SEARCHPATH) || defined(PROTO)
6128 /*
6129  * Get the file name at the cursor.
6130  * If Visual mode is active, use the selected text if it's in one line.
6131  * Returns the name in allocated memory, NULL for failure.
6132  */
6133     char_u *
6134 grab_file_name(long count, linenr_T *file_lnum)
6135 {
6136     int options = FNAME_MESS|FNAME_EXP|FNAME_REL|FNAME_UNESC;
6137 
6138     if (VIsual_active)
6139     {
6140 	int	len;
6141 	char_u	*ptr;
6142 
6143 	if (get_visual_text(NULL, &ptr, &len) == FAIL)
6144 	    return NULL;
6145 	return find_file_name_in_path(ptr, len, options,
6146 						     count, curbuf->b_ffname);
6147     }
6148     return file_name_at_cursor(options | FNAME_HYP, count, file_lnum);
6149 
6150 }
6151 
6152 /*
6153  * Return the file name under or after the cursor.
6154  *
6155  * The 'path' option is searched if the file name is not absolute.
6156  * The string returned has been alloc'ed and should be freed by the caller.
6157  * NULL is returned if the file name or file is not found.
6158  *
6159  * options:
6160  * FNAME_MESS	    give error messages
6161  * FNAME_EXP	    expand to path
6162  * FNAME_HYP	    check for hypertext link
6163  * FNAME_INCL	    apply "includeexpr"
6164  */
6165     char_u *
6166 file_name_at_cursor(int options, long count, linenr_T *file_lnum)
6167 {
6168     return file_name_in_line(ml_get_curline(),
6169 		      curwin->w_cursor.col, options, count, curbuf->b_ffname,
6170 		      file_lnum);
6171 }
6172 
6173 /*
6174  * Return the name of the file under or after ptr[col].
6175  * Otherwise like file_name_at_cursor().
6176  */
6177     char_u *
6178 file_name_in_line(
6179     char_u	*line,
6180     int		col,
6181     int		options,
6182     long	count,
6183     char_u	*rel_fname,	/* file we are searching relative to */
6184     linenr_T	*file_lnum)	/* line number after the file name */
6185 {
6186     char_u	*ptr;
6187     int		len;
6188 
6189     /*
6190      * search forward for what could be the start of a file name
6191      */
6192     ptr = line + col;
6193     while (*ptr != NUL && !vim_isfilec(*ptr))
6194 	MB_PTR_ADV(ptr);
6195     if (*ptr == NUL)		/* nothing found */
6196     {
6197 	if (options & FNAME_MESS)
6198 	    EMSG(_("E446: No file name under cursor"));
6199 	return NULL;
6200     }
6201 
6202     /*
6203      * Search backward for first char of the file name.
6204      * Go one char back to ":" before "//" even when ':' is not in 'isfname'.
6205      */
6206     while (ptr > line)
6207     {
6208 #ifdef FEAT_MBYTE
6209 	if (has_mbyte && (len = (*mb_head_off)(line, ptr - 1)) > 0)
6210 	    ptr -= len + 1;
6211 	else
6212 #endif
6213 	if (vim_isfilec(ptr[-1])
6214 		|| ((options & FNAME_HYP) && path_is_url(ptr - 1)))
6215 	    --ptr;
6216 	else
6217 	    break;
6218     }
6219 
6220     /*
6221      * Search forward for the last char of the file name.
6222      * Also allow "://" when ':' is not in 'isfname'.
6223      */
6224     len = 0;
6225     while (vim_isfilec(ptr[len]) || (ptr[len] == '\\' && ptr[len + 1] == ' ')
6226 			 || ((options & FNAME_HYP) && path_is_url(ptr + len)))
6227     {
6228 	if (ptr[len] == '\\')
6229 	    /* Skip over the "\" in "\ ". */
6230 	    ++len;
6231 #ifdef FEAT_MBYTE
6232 	if (has_mbyte)
6233 	    len += (*mb_ptr2len)(ptr + len);
6234 	else
6235 #endif
6236 	    ++len;
6237     }
6238 
6239     /*
6240      * If there is trailing punctuation, remove it.
6241      * But don't remove "..", could be a directory name.
6242      */
6243     if (len > 2 && vim_strchr((char_u *)".,:;!", ptr[len - 1]) != NULL
6244 						       && ptr[len - 2] != '.')
6245 	--len;
6246 
6247     if (file_lnum != NULL)
6248     {
6249 	char_u *p;
6250 
6251 	/* Get the number after the file name and a separator character */
6252 	p = ptr + len;
6253 	p = skipwhite(p);
6254 	if (*p != NUL)
6255 	{
6256 	    if (!isdigit(*p))
6257 		++p;		    /* skip the separator */
6258 	    p = skipwhite(p);
6259 	    if (isdigit(*p))
6260 		*file_lnum = (int)getdigits(&p);
6261 	}
6262     }
6263 
6264     return find_file_name_in_path(ptr, len, options, count, rel_fname);
6265 }
6266 
6267 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6268 static char_u *eval_includeexpr(char_u *ptr, int len);
6269 
6270     static char_u *
6271 eval_includeexpr(char_u *ptr, int len)
6272 {
6273     char_u	*res;
6274 
6275     set_vim_var_string(VV_FNAME, ptr, len);
6276     res = eval_to_string_safe(curbuf->b_p_inex, NULL,
6277 		      was_set_insecurely((char_u *)"includeexpr", OPT_LOCAL));
6278     set_vim_var_string(VV_FNAME, NULL, 0);
6279     return res;
6280 }
6281 #endif
6282 
6283 /*
6284  * Return the name of the file ptr[len] in 'path'.
6285  * Otherwise like file_name_at_cursor().
6286  */
6287     char_u *
6288 find_file_name_in_path(
6289     char_u	*ptr,
6290     int		len,
6291     int		options,
6292     long	count,
6293     char_u	*rel_fname)	/* file we are searching relative to */
6294 {
6295     char_u	*file_name;
6296     int		c;
6297 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6298     char_u	*tofree = NULL;
6299 
6300     if ((options & FNAME_INCL) && *curbuf->b_p_inex != NUL)
6301     {
6302 	tofree = eval_includeexpr(ptr, len);
6303 	if (tofree != NULL)
6304 	{
6305 	    ptr = tofree;
6306 	    len = (int)STRLEN(ptr);
6307 	}
6308     }
6309 # endif
6310 
6311     if (options & FNAME_EXP)
6312     {
6313 	file_name = find_file_in_path(ptr, len, options & ~FNAME_MESS,
6314 							     TRUE, rel_fname);
6315 
6316 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6317 	/*
6318 	 * If the file could not be found in a normal way, try applying
6319 	 * 'includeexpr' (unless done already).
6320 	 */
6321 	if (file_name == NULL
6322 		&& !(options & FNAME_INCL) && *curbuf->b_p_inex != NUL)
6323 	{
6324 	    tofree = eval_includeexpr(ptr, len);
6325 	    if (tofree != NULL)
6326 	    {
6327 		ptr = tofree;
6328 		len = (int)STRLEN(ptr);
6329 		file_name = find_file_in_path(ptr, len, options & ~FNAME_MESS,
6330 							     TRUE, rel_fname);
6331 	    }
6332 	}
6333 # endif
6334 	if (file_name == NULL && (options & FNAME_MESS))
6335 	{
6336 	    c = ptr[len];
6337 	    ptr[len] = NUL;
6338 	    EMSG2(_("E447: Can't find file \"%s\" in path"), ptr);
6339 	    ptr[len] = c;
6340 	}
6341 
6342 	/* Repeat finding the file "count" times.  This matters when it
6343 	 * appears several times in the path. */
6344 	while (file_name != NULL && --count > 0)
6345 	{
6346 	    vim_free(file_name);
6347 	    file_name = find_file_in_path(ptr, len, options, FALSE, rel_fname);
6348 	}
6349     }
6350     else
6351 	file_name = vim_strnsave(ptr, len);
6352 
6353 # if defined(FEAT_FIND_ID) && defined(FEAT_EVAL)
6354     vim_free(tofree);
6355 # endif
6356 
6357     return file_name;
6358 }
6359 #endif /* FEAT_SEARCHPATH */
6360 
6361 /*
6362  * Check if the "://" of a URL is at the pointer, return URL_SLASH.
6363  * Also check for ":\\", which MS Internet Explorer accepts, return
6364  * URL_BACKSLASH.
6365  */
6366     static int
6367 path_is_url(char_u *p)
6368 {
6369     if (STRNCMP(p, "://", (size_t)3) == 0)
6370 	return URL_SLASH;
6371     else if (STRNCMP(p, ":\\\\", (size_t)3) == 0)
6372 	return URL_BACKSLASH;
6373     return 0;
6374 }
6375 
6376 /*
6377  * Check if "fname" starts with "name://".  Return URL_SLASH if it does.
6378  * Return URL_BACKSLASH for "name:\\".
6379  * Return zero otherwise.
6380  */
6381     int
6382 path_with_url(char_u *fname)
6383 {
6384     char_u *p;
6385 
6386     for (p = fname; isalpha(*p); ++p)
6387 	;
6388     return path_is_url(p);
6389 }
6390 
6391 /*
6392  * Return TRUE if "name" is a full (absolute) path name or URL.
6393  */
6394     int
6395 vim_isAbsName(char_u *name)
6396 {
6397     return (path_with_url(name) != 0 || mch_isFullName(name));
6398 }
6399 
6400 /*
6401  * Get absolute file name into buffer "buf[len]".
6402  *
6403  * return FAIL for failure, OK otherwise
6404  */
6405     int
6406 vim_FullName(
6407     char_u	*fname,
6408     char_u	*buf,
6409     int		len,
6410     int		force)	    /* force expansion even when already absolute */
6411 {
6412     int		retval = OK;
6413     int		url;
6414 
6415     *buf = NUL;
6416     if (fname == NULL)
6417 	return FAIL;
6418 
6419     url = path_with_url(fname);
6420     if (!url)
6421 	retval = mch_FullName(fname, buf, len, force);
6422     if (url || retval == FAIL)
6423     {
6424 	/* something failed; use the file name (truncate when too long) */
6425 	vim_strncpy(buf, fname, len - 1);
6426     }
6427 #if defined(MACOS_CLASSIC) || defined(MSWIN)
6428     slash_adjust(buf);
6429 #endif
6430     return retval;
6431 }
6432 
6433 /*
6434  * Return the minimal number of rows that is needed on the screen to display
6435  * the current number of windows.
6436  */
6437     int
6438 min_rows(void)
6439 {
6440     int		total;
6441 #ifdef FEAT_WINDOWS
6442     tabpage_T	*tp;
6443     int		n;
6444 #endif
6445 
6446     if (firstwin == NULL)	/* not initialized yet */
6447 	return MIN_LINES;
6448 
6449 #ifdef FEAT_WINDOWS
6450     total = 0;
6451     FOR_ALL_TABPAGES(tp)
6452     {
6453 	n = frame_minheight(tp->tp_topframe, NULL);
6454 	if (total < n)
6455 	    total = n;
6456     }
6457     total += tabline_height();
6458 #else
6459     total = 1;		/* at least one window should have a line! */
6460 #endif
6461     total += 1;		/* count the room for the command line */
6462     return total;
6463 }
6464 
6465 /*
6466  * Return TRUE if there is only one window (in the current tab page), not
6467  * counting a help or preview window, unless it is the current window.
6468  * Does not count "aucmd_win".
6469  */
6470     int
6471 only_one_window(void)
6472 {
6473 #ifdef FEAT_WINDOWS
6474     int		count = 0;
6475     win_T	*wp;
6476 
6477     /* If there is another tab page there always is another window. */
6478     if (first_tabpage->tp_next != NULL)
6479 	return FALSE;
6480 
6481     FOR_ALL_WINDOWS(wp)
6482 	if (wp->w_buffer != NULL
6483 		&& (!((bt_help(wp->w_buffer) && !bt_help(curbuf))
6484 # ifdef FEAT_QUICKFIX
6485 		    || wp->w_p_pvw
6486 # endif
6487 	     ) || wp == curwin)
6488 # ifdef FEAT_AUTOCMD
6489 		&& wp != aucmd_win
6490 # endif
6491 	   )
6492 	    ++count;
6493     return (count <= 1);
6494 #else
6495     return TRUE;
6496 #endif
6497 }
6498 
6499 #if defined(FEAT_WINDOWS) || defined(FEAT_AUTOCMD) || defined(PROTO)
6500 /*
6501  * Correct the cursor line number in other windows.  Used after changing the
6502  * current buffer, and before applying autocommands.
6503  * When "do_curwin" is TRUE, also check current window.
6504  */
6505     void
6506 check_lnums(int do_curwin)
6507 {
6508     win_T	*wp;
6509 
6510 #ifdef FEAT_WINDOWS
6511     tabpage_T	*tp;
6512 
6513     FOR_ALL_TAB_WINDOWS(tp, wp)
6514 	if ((do_curwin || wp != curwin) && wp->w_buffer == curbuf)
6515 #else
6516     wp = curwin;
6517     if (do_curwin)
6518 #endif
6519 	{
6520 	    if (wp->w_cursor.lnum > curbuf->b_ml.ml_line_count)
6521 		wp->w_cursor.lnum = curbuf->b_ml.ml_line_count;
6522 	    if (wp->w_topline > curbuf->b_ml.ml_line_count)
6523 		wp->w_topline = curbuf->b_ml.ml_line_count;
6524 	}
6525 }
6526 #endif
6527 
6528 #if defined(FEAT_WINDOWS) || defined(PROTO)
6529 
6530 /*
6531  * A snapshot of the window sizes, to restore them after closing the help
6532  * window.
6533  * Only these fields are used:
6534  * fr_layout
6535  * fr_width
6536  * fr_height
6537  * fr_next
6538  * fr_child
6539  * fr_win (only valid for the old curwin, NULL otherwise)
6540  */
6541 
6542 /*
6543  * Create a snapshot of the current frame sizes.
6544  */
6545     void
6546 make_snapshot(int idx)
6547 {
6548     clear_snapshot(curtab, idx);
6549     make_snapshot_rec(topframe, &curtab->tp_snapshot[idx]);
6550 }
6551 
6552     static void
6553 make_snapshot_rec(frame_T *fr, frame_T **frp)
6554 {
6555     *frp = (frame_T *)alloc_clear((unsigned)sizeof(frame_T));
6556     if (*frp == NULL)
6557 	return;
6558     (*frp)->fr_layout = fr->fr_layout;
6559     (*frp)->fr_width = fr->fr_width;
6560     (*frp)->fr_height = fr->fr_height;
6561     if (fr->fr_next != NULL)
6562 	make_snapshot_rec(fr->fr_next, &((*frp)->fr_next));
6563     if (fr->fr_child != NULL)
6564 	make_snapshot_rec(fr->fr_child, &((*frp)->fr_child));
6565     if (fr->fr_layout == FR_LEAF && fr->fr_win == curwin)
6566 	(*frp)->fr_win = curwin;
6567 }
6568 
6569 /*
6570  * Remove any existing snapshot.
6571  */
6572     static void
6573 clear_snapshot(tabpage_T *tp, int idx)
6574 {
6575     clear_snapshot_rec(tp->tp_snapshot[idx]);
6576     tp->tp_snapshot[idx] = NULL;
6577 }
6578 
6579     static void
6580 clear_snapshot_rec(frame_T *fr)
6581 {
6582     if (fr != NULL)
6583     {
6584 	clear_snapshot_rec(fr->fr_next);
6585 	clear_snapshot_rec(fr->fr_child);
6586 	vim_free(fr);
6587     }
6588 }
6589 
6590 /*
6591  * Restore a previously created snapshot, if there is any.
6592  * This is only done if the screen size didn't change and the window layout is
6593  * still the same.
6594  */
6595     void
6596 restore_snapshot(
6597     int		idx,
6598     int		close_curwin)	    /* closing current window */
6599 {
6600     win_T	*wp;
6601 
6602     if (curtab->tp_snapshot[idx] != NULL
6603 	    && curtab->tp_snapshot[idx]->fr_width == topframe->fr_width
6604 	    && curtab->tp_snapshot[idx]->fr_height == topframe->fr_height
6605 	    && check_snapshot_rec(curtab->tp_snapshot[idx], topframe) == OK)
6606     {
6607 	wp = restore_snapshot_rec(curtab->tp_snapshot[idx], topframe);
6608 	win_comp_pos();
6609 	if (wp != NULL && close_curwin)
6610 	    win_goto(wp);
6611 	redraw_all_later(CLEAR);
6612     }
6613     clear_snapshot(curtab, idx);
6614 }
6615 
6616 /*
6617  * Check if frames "sn" and "fr" have the same layout, same following frames
6618  * and same children.  And the window pointer is valid.
6619  */
6620     static int
6621 check_snapshot_rec(frame_T *sn, frame_T *fr)
6622 {
6623     if (sn->fr_layout != fr->fr_layout
6624 	    || (sn->fr_next == NULL) != (fr->fr_next == NULL)
6625 	    || (sn->fr_child == NULL) != (fr->fr_child == NULL)
6626 	    || (sn->fr_next != NULL
6627 		&& check_snapshot_rec(sn->fr_next, fr->fr_next) == FAIL)
6628 	    || (sn->fr_child != NULL
6629 		&& check_snapshot_rec(sn->fr_child, fr->fr_child) == FAIL)
6630 	    || (sn->fr_win != NULL && !win_valid(sn->fr_win)))
6631 	return FAIL;
6632     return OK;
6633 }
6634 
6635 /*
6636  * Copy the size of snapshot frame "sn" to frame "fr".  Do the same for all
6637  * following frames and children.
6638  * Returns a pointer to the old current window, or NULL.
6639  */
6640     static win_T *
6641 restore_snapshot_rec(frame_T *sn, frame_T *fr)
6642 {
6643     win_T	*wp = NULL;
6644     win_T	*wp2;
6645 
6646     fr->fr_height = sn->fr_height;
6647     fr->fr_width = sn->fr_width;
6648     if (fr->fr_layout == FR_LEAF)
6649     {
6650 	frame_new_height(fr, fr->fr_height, FALSE, FALSE);
6651 	frame_new_width(fr, fr->fr_width, FALSE, FALSE);
6652 	wp = sn->fr_win;
6653     }
6654     if (sn->fr_next != NULL)
6655     {
6656 	wp2 = restore_snapshot_rec(sn->fr_next, fr->fr_next);
6657 	if (wp2 != NULL)
6658 	    wp = wp2;
6659     }
6660     if (sn->fr_child != NULL)
6661     {
6662 	wp2 = restore_snapshot_rec(sn->fr_child, fr->fr_child);
6663 	if (wp2 != NULL)
6664 	    wp = wp2;
6665     }
6666     return wp;
6667 }
6668 
6669 #endif
6670 
6671 #if defined(FEAT_EVAL) || defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) \
6672 	|| defined(PROTO)
6673 /*
6674  * Set "win" to be the curwin and "tp" to be the current tab page.
6675  * restore_win() MUST be called to undo, also when FAIL is returned.
6676  * No autocommands will be executed until restore_win() is called.
6677  * When "no_display" is TRUE the display won't be affected, no redraw is
6678  * triggered, another tabpage access is limited.
6679  * Returns FAIL if switching to "win" failed.
6680  */
6681     int
6682 switch_win(
6683     win_T	**save_curwin UNUSED,
6684     tabpage_T	**save_curtab UNUSED,
6685     win_T	*win UNUSED,
6686     tabpage_T	*tp UNUSED,
6687     int		no_display UNUSED)
6688 {
6689 # ifdef FEAT_AUTOCMD
6690     block_autocmds();
6691 # endif
6692 # ifdef FEAT_WINDOWS
6693     *save_curwin = curwin;
6694     if (tp != NULL)
6695     {
6696 	*save_curtab = curtab;
6697 	if (no_display)
6698 	{
6699 	    curtab->tp_firstwin = firstwin;
6700 	    curtab->tp_lastwin = lastwin;
6701 	    curtab = tp;
6702 	    firstwin = curtab->tp_firstwin;
6703 	    lastwin = curtab->tp_lastwin;
6704 	}
6705 	else
6706 	    goto_tabpage_tp(tp, FALSE, FALSE);
6707     }
6708     if (!win_valid(win))
6709 	return FAIL;
6710     curwin = win;
6711     curbuf = curwin->w_buffer;
6712 # endif
6713     return OK;
6714 }
6715 
6716 /*
6717  * Restore current tabpage and window saved by switch_win(), if still valid.
6718  * When "no_display" is TRUE the display won't be affected, no redraw is
6719  * triggered.
6720  */
6721     void
6722 restore_win(
6723     win_T	*save_curwin UNUSED,
6724     tabpage_T	*save_curtab UNUSED,
6725     int		no_display UNUSED)
6726 {
6727 # ifdef FEAT_WINDOWS
6728     if (save_curtab != NULL && valid_tabpage(save_curtab))
6729     {
6730 	if (no_display)
6731 	{
6732 	    curtab->tp_firstwin = firstwin;
6733 	    curtab->tp_lastwin = lastwin;
6734 	    curtab = save_curtab;
6735 	    firstwin = curtab->tp_firstwin;
6736 	    lastwin = curtab->tp_lastwin;
6737 	}
6738 	else
6739 	    goto_tabpage_tp(save_curtab, FALSE, FALSE);
6740     }
6741     if (win_valid(save_curwin))
6742     {
6743 	curwin = save_curwin;
6744 	curbuf = curwin->w_buffer;
6745     }
6746 # endif
6747 # ifdef FEAT_AUTOCMD
6748     unblock_autocmds();
6749 # endif
6750 }
6751 
6752 /*
6753  * Make "buf" the current buffer.  restore_buffer() MUST be called to undo.
6754  * No autocommands will be executed.  Use aucmd_prepbuf() if there are any.
6755  */
6756     void
6757 switch_buffer(bufref_T *save_curbuf, buf_T *buf)
6758 {
6759 # ifdef FEAT_AUTOCMD
6760     block_autocmds();
6761 # endif
6762     set_bufref(save_curbuf, curbuf);
6763     --curbuf->b_nwindows;
6764     curbuf = buf;
6765     curwin->w_buffer = buf;
6766     ++curbuf->b_nwindows;
6767 }
6768 
6769 /*
6770  * Restore the current buffer after using switch_buffer().
6771  */
6772     void
6773 restore_buffer(bufref_T *save_curbuf)
6774 {
6775 # ifdef FEAT_AUTOCMD
6776     unblock_autocmds();
6777 # endif
6778     /* Check for valid buffer, just in case. */
6779     if (bufref_valid(save_curbuf))
6780     {
6781 	--curbuf->b_nwindows;
6782 	curwin->w_buffer = save_curbuf->br_buf;
6783 	curbuf = save_curbuf->br_buf;
6784 	++curbuf->b_nwindows;
6785     }
6786 }
6787 #endif
6788 
6789 #if (defined(FEAT_GUI) && defined(FEAT_WINDOWS)) || defined(PROTO)
6790 /*
6791  * Return TRUE if there is any vertically split window.
6792  */
6793     int
6794 win_hasvertsplit(void)
6795 {
6796     frame_T	*fr;
6797 
6798     if (topframe->fr_layout == FR_ROW)
6799 	return TRUE;
6800 
6801     if (topframe->fr_layout == FR_COL)
6802 	for (fr = topframe->fr_child; fr != NULL; fr = fr->fr_next)
6803 	    if (fr->fr_layout == FR_ROW)
6804 		return TRUE;
6805 
6806     return FALSE;
6807 }
6808 #endif
6809 
6810 #if defined(FEAT_SEARCH_EXTRA) || defined(PROTO)
6811 /*
6812  * Add match to the match list of window 'wp'.  The pattern 'pat' will be
6813  * highlighted with the group 'grp' with priority 'prio'.
6814  * Optionally, a desired ID 'id' can be specified (greater than or equal to 1).
6815  * If no particular ID is desired, -1 must be specified for 'id'.
6816  * Return ID of added match, -1 on failure.
6817  */
6818     int
6819 match_add(
6820     win_T	*wp,
6821     char_u	*grp,
6822     char_u	*pat,
6823     int		prio,
6824     int		id,
6825     list_T	*pos_list,
6826     char_u      *conceal_char UNUSED) /* pointer to conceal replacement char */
6827 {
6828     matchitem_T	*cur;
6829     matchitem_T	*prev;
6830     matchitem_T	*m;
6831     int		hlg_id;
6832     regprog_T	*regprog = NULL;
6833     int		rtype = SOME_VALID;
6834 
6835     if (*grp == NUL || (pat != NULL && *pat == NUL))
6836 	return -1;
6837     if (id < -1 || id == 0)
6838     {
6839 	EMSGN(_("E799: Invalid ID: %ld (must be greater than or equal to 1)"), id);
6840 	return -1;
6841     }
6842     if (id != -1)
6843     {
6844 	cur = wp->w_match_head;
6845 	while (cur != NULL)
6846 	{
6847 	    if (cur->id == id)
6848 	    {
6849 		EMSGN(_("E801: ID already taken: %ld"), id);
6850 		return -1;
6851 	    }
6852 	    cur = cur->next;
6853 	}
6854     }
6855     if ((hlg_id = syn_namen2id(grp, (int)STRLEN(grp))) == 0)
6856     {
6857 	EMSG2(_(e_nogroup), grp);
6858 	return -1;
6859     }
6860     if (pat != NULL && (regprog = vim_regcomp(pat, RE_MAGIC)) == NULL)
6861     {
6862 	EMSG2(_(e_invarg2), pat);
6863 	return -1;
6864     }
6865 
6866     /* Find available match ID. */
6867     while (id == -1)
6868     {
6869 	cur = wp->w_match_head;
6870 	while (cur != NULL && cur->id != wp->w_next_match_id)
6871 	    cur = cur->next;
6872 	if (cur == NULL)
6873 	    id = wp->w_next_match_id;
6874 	wp->w_next_match_id++;
6875     }
6876 
6877     /* Build new match. */
6878     m = (matchitem_T *)alloc_clear(sizeof(matchitem_T));
6879     m->id = id;
6880     m->priority = prio;
6881     m->pattern = pat == NULL ? NULL : vim_strsave(pat);
6882     m->hlg_id = hlg_id;
6883     m->match.regprog = regprog;
6884     m->match.rmm_ic = FALSE;
6885     m->match.rmm_maxcol = 0;
6886 # if defined(FEAT_CONCEAL) && defined(FEAT_MBYTE)
6887     m->conceal_char = 0;
6888     if (conceal_char != NULL)
6889 	m->conceal_char = (*mb_ptr2char)(conceal_char);
6890 # endif
6891 
6892     /* Set up position matches */
6893     if (pos_list != NULL)
6894     {
6895 	linenr_T	toplnum = 0;
6896 	linenr_T	botlnum = 0;
6897 	listitem_T	*li;
6898 	int		i;
6899 
6900 	for (i = 0, li = pos_list->lv_first; li != NULL && i < MAXPOSMATCH;
6901 							i++, li = li->li_next)
6902 	{
6903 	    linenr_T	lnum = 0;
6904 	    colnr_T	col = 0;
6905 	    int		len = 1;
6906 	    list_T	*subl;
6907 	    listitem_T	*subli;
6908 	    int		error = FALSE;
6909 
6910 	    if (li->li_tv.v_type == VAR_LIST)
6911 	    {
6912 		subl = li->li_tv.vval.v_list;
6913 		if (subl == NULL)
6914 		    goto fail;
6915 		subli = subl->lv_first;
6916 		if (subli == NULL)
6917 		    goto fail;
6918 		lnum = get_tv_number_chk(&subli->li_tv, &error);
6919 		if (error == TRUE)
6920 		    goto fail;
6921 		if (lnum == 0)
6922 		{
6923 		    --i;
6924 		    continue;
6925 		}
6926 		m->pos.pos[i].lnum = lnum;
6927 		subli = subli->li_next;
6928 		if (subli != NULL)
6929 		{
6930 		    col = get_tv_number_chk(&subli->li_tv, &error);
6931 		    if (error == TRUE)
6932 			goto fail;
6933 		    subli = subli->li_next;
6934 		    if (subli != NULL)
6935 		    {
6936 			len = get_tv_number_chk(&subli->li_tv, &error);
6937 			if (error == TRUE)
6938 			    goto fail;
6939 		    }
6940 		}
6941 		m->pos.pos[i].col = col;
6942 		m->pos.pos[i].len = len;
6943 	    }
6944 	    else if (li->li_tv.v_type == VAR_NUMBER)
6945 	    {
6946 		if (li->li_tv.vval.v_number == 0)
6947 		{
6948 		    --i;
6949 		    continue;
6950 		}
6951 		m->pos.pos[i].lnum = li->li_tv.vval.v_number;
6952 		m->pos.pos[i].col = 0;
6953 		m->pos.pos[i].len = 0;
6954 	    }
6955 	    else
6956 	    {
6957 		EMSG(_("List or number required"));
6958 		goto fail;
6959 	    }
6960 	    if (toplnum == 0 || lnum < toplnum)
6961 		toplnum = lnum;
6962 	    if (botlnum == 0 || lnum >= botlnum)
6963 		botlnum = lnum + 1;
6964 	}
6965 
6966 	/* Calculate top and bottom lines for redrawing area */
6967 	if (toplnum != 0)
6968 	{
6969 	    if (wp->w_buffer->b_mod_set)
6970 	    {
6971 		if (wp->w_buffer->b_mod_top > toplnum)
6972 		    wp->w_buffer->b_mod_top = toplnum;
6973 		if (wp->w_buffer->b_mod_bot < botlnum)
6974 		    wp->w_buffer->b_mod_bot = botlnum;
6975 	    }
6976 	    else
6977 	    {
6978 		wp->w_buffer->b_mod_set = TRUE;
6979 		wp->w_buffer->b_mod_top = toplnum;
6980 		wp->w_buffer->b_mod_bot = botlnum;
6981 		wp->w_buffer->b_mod_xlines = 0;
6982 	    }
6983 	    m->pos.toplnum = toplnum;
6984 	    m->pos.botlnum = botlnum;
6985 	    rtype = VALID;
6986 	}
6987     }
6988 
6989     /* Insert new match.  The match list is in ascending order with regard to
6990      * the match priorities. */
6991     cur = wp->w_match_head;
6992     prev = cur;
6993     while (cur != NULL && prio >= cur->priority)
6994     {
6995 	prev = cur;
6996 	cur = cur->next;
6997     }
6998     if (cur == prev)
6999 	wp->w_match_head = m;
7000     else
7001 	prev->next = m;
7002     m->next = cur;
7003 
7004     redraw_later(rtype);
7005     return id;
7006 
7007 fail:
7008     vim_free(m);
7009     return -1;
7010 }
7011 
7012 /*
7013  * Delete match with ID 'id' in the match list of window 'wp'.
7014  * Print error messages if 'perr' is TRUE.
7015  */
7016     int
7017 match_delete(win_T *wp, int id, int perr)
7018 {
7019     matchitem_T	*cur = wp->w_match_head;
7020     matchitem_T	*prev = cur;
7021     int		rtype = SOME_VALID;
7022 
7023     if (id < 1)
7024     {
7025 	if (perr == TRUE)
7026 	    EMSGN(_("E802: Invalid ID: %ld (must be greater than or equal to 1)"),
7027 									  id);
7028 	return -1;
7029     }
7030     while (cur != NULL && cur->id != id)
7031     {
7032 	prev = cur;
7033 	cur = cur->next;
7034     }
7035     if (cur == NULL)
7036     {
7037 	if (perr == TRUE)
7038 	    EMSGN(_("E803: ID not found: %ld"), id);
7039 	return -1;
7040     }
7041     if (cur == prev)
7042 	wp->w_match_head = cur->next;
7043     else
7044 	prev->next = cur->next;
7045     vim_regfree(cur->match.regprog);
7046     vim_free(cur->pattern);
7047     if (cur->pos.toplnum != 0)
7048     {
7049 	if (wp->w_buffer->b_mod_set)
7050 	{
7051 	    if (wp->w_buffer->b_mod_top > cur->pos.toplnum)
7052 		wp->w_buffer->b_mod_top = cur->pos.toplnum;
7053 	    if (wp->w_buffer->b_mod_bot < cur->pos.botlnum)
7054 		wp->w_buffer->b_mod_bot = cur->pos.botlnum;
7055 	}
7056 	else
7057 	{
7058 	    wp->w_buffer->b_mod_set = TRUE;
7059 	    wp->w_buffer->b_mod_top = cur->pos.toplnum;
7060 	    wp->w_buffer->b_mod_bot = cur->pos.botlnum;
7061 	    wp->w_buffer->b_mod_xlines = 0;
7062 	}
7063 	rtype = VALID;
7064     }
7065     vim_free(cur);
7066     redraw_later(rtype);
7067     return 0;
7068 }
7069 
7070 /*
7071  * Delete all matches in the match list of window 'wp'.
7072  */
7073     void
7074 clear_matches(win_T *wp)
7075 {
7076     matchitem_T *m;
7077 
7078     while (wp->w_match_head != NULL)
7079     {
7080 	m = wp->w_match_head->next;
7081 	vim_regfree(wp->w_match_head->match.regprog);
7082 	vim_free(wp->w_match_head->pattern);
7083 	vim_free(wp->w_match_head);
7084 	wp->w_match_head = m;
7085     }
7086     redraw_later(SOME_VALID);
7087 }
7088 
7089 /*
7090  * Get match from ID 'id' in window 'wp'.
7091  * Return NULL if match not found.
7092  */
7093     matchitem_T *
7094 get_match(win_T *wp, int id)
7095 {
7096     matchitem_T *cur = wp->w_match_head;
7097 
7098     while (cur != NULL && cur->id != id)
7099 	cur = cur->next;
7100     return cur;
7101 }
7102 #endif
7103 
7104 #if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) || defined(PROTO)
7105     int
7106 get_win_number(win_T *wp, win_T *first_win)
7107 {
7108     int		i = 1;
7109     win_T	*w;
7110 
7111     for (w = first_win; w != NULL && w != wp; w = W_NEXT(w))
7112 	++i;
7113 
7114     if (w == NULL)
7115 	return 0;
7116     else
7117 	return i;
7118 }
7119 
7120     int
7121 get_tab_number(tabpage_T *tp UNUSED)
7122 {
7123     int		i = 1;
7124 # ifdef FEAT_WINDOWS
7125     tabpage_T	*t;
7126 
7127     for (t = first_tabpage; t != NULL && t != tp; t = t->tp_next)
7128 	++i;
7129 
7130     if (t == NULL)
7131 	return 0;
7132     else
7133 # endif
7134 	return i;
7135 }
7136 #endif
7137 
7138 #if defined(FEAT_WINDOWS) || defined(PROTO)
7139 /*
7140  * Return TRUE if "topfrp" and its children are at the right height.
7141  */
7142     static int
7143 frame_check_height(frame_T *topfrp, int height)
7144 {
7145     frame_T *frp;
7146 
7147     if (topfrp->fr_height != height)
7148 	return FALSE;
7149 
7150     if (topfrp->fr_layout == FR_ROW)
7151 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
7152 	    if (frp->fr_height != height)
7153 		return FALSE;
7154 
7155     return TRUE;
7156 }
7157 #endif
7158 
7159 #if defined(FEAT_WINDOWS) || defined(PROTO)
7160 /*
7161  * Return TRUE if "topfrp" and its children are at the right width.
7162  */
7163     static int
7164 frame_check_width(frame_T *topfrp, int width)
7165 {
7166     frame_T *frp;
7167 
7168     if (topfrp->fr_width != width)
7169 	return FALSE;
7170 
7171     if (topfrp->fr_layout == FR_COL)
7172 	for (frp = topfrp->fr_child; frp != NULL; frp = frp->fr_next)
7173 	    if (frp->fr_width != width)
7174 		return FALSE;
7175 
7176     return TRUE;
7177 }
7178 #endif
7179 
7180 #if defined(FEAT_EVAL) || defined(PROTO)
7181     int
7182 win_getid(typval_T *argvars)
7183 {
7184     int	    winnr;
7185     win_T   *wp;
7186 
7187     if (argvars[0].v_type == VAR_UNKNOWN)
7188 	return curwin->w_id;
7189     winnr = get_tv_number(&argvars[0]);
7190     if (winnr > 0)
7191     {
7192 	if (argvars[1].v_type == VAR_UNKNOWN)
7193 	    wp = firstwin;
7194 	else
7195 	{
7196 	    tabpage_T	*tp;
7197 	    int		tabnr = get_tv_number(&argvars[1]);
7198 
7199 	    FOR_ALL_TABPAGES(tp)
7200 		if (--tabnr == 0)
7201 		    break;
7202 	    if (tp == NULL)
7203 		return -1;
7204 	    if (tp == curtab)
7205 		wp = firstwin;
7206 	    else
7207 		wp = tp->tp_firstwin;
7208 	}
7209 	for ( ; wp != NULL; wp = wp->w_next)
7210 	    if (--winnr == 0)
7211 		return wp->w_id;
7212     }
7213     return 0;
7214 }
7215 
7216     int
7217 win_gotoid(typval_T *argvars)
7218 {
7219     win_T	*wp;
7220     tabpage_T   *tp;
7221     int		id = get_tv_number(&argvars[0]);
7222 
7223     FOR_ALL_TAB_WINDOWS(tp, wp)
7224 	    if (wp->w_id == id)
7225 	    {
7226 		goto_tabpage_win(tp, wp);
7227 		return 1;
7228 	    }
7229     return 0;
7230 }
7231 
7232     void
7233 win_id2tabwin(typval_T *argvars, list_T *list)
7234 {
7235     win_T	*wp;
7236     tabpage_T   *tp;
7237     int		winnr = 1;
7238     int		tabnr = 1;
7239     int		id = get_tv_number(&argvars[0]);
7240 
7241     FOR_ALL_TABPAGES(tp)
7242     {
7243 	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
7244 	{
7245 	    if (wp->w_id == id)
7246 	    {
7247 		list_append_number(list, tabnr);
7248 		list_append_number(list, winnr);
7249 		return;
7250 	    }
7251 	    ++winnr;
7252 	}
7253 	++tabnr;
7254 	winnr = 1;
7255     }
7256     list_append_number(list, 0);
7257     list_append_number(list, 0);
7258 }
7259 
7260     win_T *
7261 win_id2wp(typval_T *argvars)
7262 {
7263     win_T	*wp;
7264     tabpage_T   *tp;
7265     int		id = get_tv_number(&argvars[0]);
7266 
7267     FOR_ALL_TAB_WINDOWS(tp, wp)
7268 	if (wp->w_id == id)
7269 	    return wp;
7270 
7271     return NULL;
7272 }
7273 
7274     int
7275 win_id2win(typval_T *argvars)
7276 {
7277     win_T   *wp;
7278     int	    nr = 1;
7279     int	    id = get_tv_number(&argvars[0]);
7280 
7281     FOR_ALL_WINDOWS(wp)
7282     {
7283 	if (wp->w_id == id)
7284 	    return nr;
7285 	++nr;
7286     }
7287     return 0;
7288 }
7289 
7290     void
7291 win_findbuf(typval_T *argvars, list_T *list)
7292 {
7293     win_T	*wp;
7294     tabpage_T   *tp;
7295     int		bufnr = get_tv_number(&argvars[0]);
7296 
7297     FOR_ALL_TAB_WINDOWS(tp, wp)
7298 	    if (wp->w_buffer->b_fnum == bufnr)
7299 		list_append_number(list, wp->w_id);
7300 }
7301 
7302 #endif
7303