xref: /vim-8.2.3635/src/screen.c (revision 81ea1dfb)
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 copying and usage conditions.
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 /*
11  * screen.c: Lower level code for displaying on the screen.
12  *
13  * Output to the screen (console, terminal emulator or GUI window) is minimized
14  * by remembering what is already on the screen, and only updating the parts
15  * that changed.
16  *
17  * ScreenLines[off]  Contains a copy of the whole screen, as it is currently
18  *		     displayed (excluding text written by external commands).
19  * ScreenAttrs[off]  Contains the associated attributes.
20  * LineOffset[row]   Contains the offset into ScreenLines*[] and ScreenAttrs[]
21  *		     for each line.
22  * LineWraps[row]    Flag for each line whether it wraps to the next line.
23  *
24  * For double-byte characters, two consecutive bytes in ScreenLines[] can form
25  * one character which occupies two display cells.
26  * For UTF-8 a multi-byte character is converted to Unicode and stored in
27  * ScreenLinesUC[].  ScreenLines[] contains the first byte only.  For an ASCII
28  * character without composing chars ScreenLinesUC[] will be 0 and
29  * ScreenLinesC[][] is not used.  When the character occupies two display
30  * cells the next byte in ScreenLines[] is 0.
31  * ScreenLinesC[][] contain up to 'maxcombine' composing characters
32  * (drawn on top of the first character).  There is 0 after the last one used.
33  * ScreenLines2[] is only used for euc-jp to store the second byte if the
34  * first byte is 0x8e (single-width character).
35  *
36  * The screen_*() functions write to the screen and handle updating
37  * ScreenLines[].
38  */
39 
40 #include "vim.h"
41 
42 /*
43  * The attributes that are actually active for writing to the screen.
44  */
45 static int	screen_attr = 0;
46 
47 static void screen_char_2(unsigned off, int row, int col);
48 static void screenclear2(void);
49 static void lineclear(unsigned off, int width, int attr);
50 static void lineinvalid(unsigned off, int width);
51 static int win_do_lines(win_T *wp, int row, int line_count, int mayclear, int del, int clear_attr);
52 static void win_rest_invalid(win_T *wp);
53 static void msg_pos_mode(void);
54 static void recording_mode(int attr);
55 
56 // Ugly global: overrule attribute used by screen_char()
57 static int screen_char_attr = 0;
58 
59 #if defined(FEAT_CONCEAL) || defined(PROTO)
60 /*
61  * Return TRUE if the cursor line in window "wp" may be concealed, according
62  * to the 'concealcursor' option.
63  */
64     int
65 conceal_cursor_line(win_T *wp)
66 {
67     int		c;
68 
69     if (*wp->w_p_cocu == NUL)
70 	return FALSE;
71     if (get_real_state() & VISUAL)
72 	c = 'v';
73     else if (State & INSERT)
74 	c = 'i';
75     else if (State & NORMAL)
76 	c = 'n';
77     else if (State & CMDLINE)
78 	c = 'c';
79     else
80 	return FALSE;
81     return vim_strchr(wp->w_p_cocu, c) != NULL;
82 }
83 
84 /*
85  * Check if the cursor line needs to be redrawn because of 'concealcursor'.
86  */
87     void
88 conceal_check_cursor_line(void)
89 {
90     if (curwin->w_p_cole > 0 && conceal_cursor_line(curwin))
91     {
92 	need_cursor_line_redraw = TRUE;
93 	// Need to recompute cursor column, e.g., when starting Visual mode
94 	// without concealing.
95 	curs_columns(TRUE);
96     }
97 }
98 #endif
99 
100 /*
101  * Get 'wincolor' attribute for window "wp".  If not set and "wp" is a popup
102  * window then get the "Pmenu" highlight attribute.
103  */
104     int
105 get_wcr_attr(win_T *wp)
106 {
107     int wcr_attr = 0;
108 
109     if (*wp->w_p_wcr != NUL)
110 	wcr_attr = syn_name2attr(wp->w_p_wcr);
111 #ifdef FEAT_PROP_POPUP
112     else if (WIN_IS_POPUP(wp))
113     {
114 	if (wp->w_popup_flags & POPF_INFO)
115 	    wcr_attr = HL_ATTR(HLF_PSI);    // PmenuSel
116 	else
117 	    wcr_attr = HL_ATTR(HLF_PNI);    // Pmenu
118     }
119 #endif
120     return wcr_attr;
121 }
122 
123 /*
124  * Call screen_fill() with the columns adjusted for 'rightleft' if needed.
125  * Return the new offset.
126  */
127     static int
128 screen_fill_end(
129 	win_T *wp,
130 	int	c1,
131 	int	c2,
132 	int	off,
133 	int	width,
134 	int	row,
135 	int	endrow,
136 	int	attr)
137 {
138     int	    nn = off + width;
139 
140     if (nn > wp->w_width)
141 	nn = wp->w_width;
142 #ifdef FEAT_RIGHTLEFT
143     if (wp->w_p_rl)
144     {
145 	screen_fill(W_WINROW(wp) + row, W_WINROW(wp) + endrow,
146 		W_ENDCOL(wp) - nn, (int)W_ENDCOL(wp) - off,
147 		c1, c2, attr);
148     }
149     else
150 #endif
151 	screen_fill(W_WINROW(wp) + row, W_WINROW(wp) + endrow,
152 		wp->w_wincol + off, (int)wp->w_wincol + nn,
153 		c1, c2, attr);
154     return nn;
155 }
156 
157 /*
158  * Clear lines near the end the window and mark the unused lines with "c1".
159  * use "c2" as the filler character.
160  * When "draw_margin" is TRUE then draw the sign, fold and number columns.
161  */
162     void
163 win_draw_end(
164     win_T	*wp,
165     int		c1,
166     int		c2,
167     int		draw_margin,
168     int		row,
169     int		endrow,
170     hlf_T	hl)
171 {
172     int		n = 0;
173     int		attr = HL_ATTR(hl);
174     int		wcr_attr = get_wcr_attr(wp);
175 
176     attr = hl_combine_attr(wcr_attr, attr);
177 
178     if (draw_margin)
179     {
180 #ifdef FEAT_FOLDING
181 	int	fdc = compute_foldcolumn(wp, 0);
182 
183 	if (fdc > 0)
184 	    // draw the fold column
185 	    n = screen_fill_end(wp, ' ', ' ', n, fdc,
186 		      row, endrow, hl_combine_attr(wcr_attr, HL_ATTR(HLF_FC)));
187 #endif
188 #ifdef FEAT_SIGNS
189 	if (signcolumn_on(wp))
190 	    // draw the sign column
191 	    n = screen_fill_end(wp, ' ', ' ', n, 2,
192 		      row, endrow, hl_combine_attr(wcr_attr, HL_ATTR(HLF_SC)));
193 #endif
194 	if ((wp->w_p_nu || wp->w_p_rnu)
195 				  && vim_strchr(p_cpo, CPO_NUMCOL) == NULL)
196 	    // draw the number column
197 	    n = screen_fill_end(wp, ' ', ' ', n, number_width(wp) + 1,
198 		       row, endrow, hl_combine_attr(wcr_attr, HL_ATTR(HLF_N)));
199     }
200 
201 #ifdef FEAT_RIGHTLEFT
202     if (wp->w_p_rl)
203     {
204 	screen_fill(W_WINROW(wp) + row, W_WINROW(wp) + endrow,
205 		wp->w_wincol, W_ENDCOL(wp) - 1 - n,
206 		c2, c2, attr);
207 	screen_fill(W_WINROW(wp) + row, W_WINROW(wp) + endrow,
208 		W_ENDCOL(wp) - 1 - n, W_ENDCOL(wp) - n,
209 		c1, c2, attr);
210     }
211     else
212 #endif
213     {
214 	screen_fill(W_WINROW(wp) + row, W_WINROW(wp) + endrow,
215 		wp->w_wincol + n, (int)W_ENDCOL(wp),
216 		c1, c2, attr);
217     }
218 
219     set_empty_rows(wp, row);
220 }
221 
222 #if defined(FEAT_FOLDING) || defined(PROTO)
223 /*
224  * Compute the width of the foldcolumn.  Based on 'foldcolumn' and how much
225  * space is available for window "wp", minus "col".
226  */
227     int
228 compute_foldcolumn(win_T *wp, int col)
229 {
230     int fdc = wp->w_p_fdc;
231     int wmw = wp == curwin && p_wmw == 0 ? 1 : p_wmw;
232     int wwidth = wp->w_width;
233 
234     if (fdc > wwidth - (col + wmw))
235 	fdc = wwidth - (col + wmw);
236     return fdc;
237 }
238 
239 /*
240  * Fill the foldcolumn at "p" for window "wp".
241  * Only to be called when 'foldcolumn' > 0.
242  */
243     void
244 fill_foldcolumn(
245     char_u	*p,
246     win_T	*wp,
247     int		closed,		// TRUE of FALSE
248     linenr_T	lnum)		// current line number
249 {
250     int		i = 0;
251     int		level;
252     int		first_level;
253     int		empty;
254     int		fdc = compute_foldcolumn(wp, 0);
255 
256     // Init to all spaces.
257     vim_memset(p, ' ', (size_t)fdc);
258 
259     level = win_foldinfo.fi_level;
260     if (level > 0)
261     {
262 	// If there is only one column put more info in it.
263 	empty = (fdc == 1) ? 0 : 1;
264 
265 	// If the column is too narrow, we start at the lowest level that
266 	// fits and use numbers to indicated the depth.
267 	first_level = level - fdc - closed + 1 + empty;
268 	if (first_level < 1)
269 	    first_level = 1;
270 
271 	for (i = 0; i + empty < fdc; ++i)
272 	{
273 	    if (win_foldinfo.fi_lnum == lnum
274 			      && first_level + i >= win_foldinfo.fi_low_level)
275 		p[i] = '-';
276 	    else if (first_level == 1)
277 		p[i] = '|';
278 	    else if (first_level + i <= 9)
279 		p[i] = '0' + first_level + i;
280 	    else
281 		p[i] = '>';
282 	    if (first_level + i == level)
283 		break;
284 	}
285     }
286     if (closed)
287 	p[i >= fdc ? i - 1 : i] = '+';
288 }
289 #endif // FEAT_FOLDING
290 
291 /*
292  * Return if the composing characters at "off_from" and "off_to" differ.
293  * Only to be used when ScreenLinesUC[off_from] != 0.
294  */
295     static int
296 comp_char_differs(int off_from, int off_to)
297 {
298     int	    i;
299 
300     for (i = 0; i < Screen_mco; ++i)
301     {
302 	if (ScreenLinesC[i][off_from] != ScreenLinesC[i][off_to])
303 	    return TRUE;
304 	if (ScreenLinesC[i][off_from] == 0)
305 	    break;
306     }
307     return FALSE;
308 }
309 
310 /*
311  * Check whether the given character needs redrawing:
312  * - the (first byte of the) character is different
313  * - the attributes are different
314  * - the character is multi-byte and the next byte is different
315  * - the character is two cells wide and the second cell differs.
316  */
317     static int
318 char_needs_redraw(int off_from, int off_to, int cols)
319 {
320     if (cols > 0
321 	    && ((ScreenLines[off_from] != ScreenLines[off_to]
322 		    || ScreenAttrs[off_from] != ScreenAttrs[off_to])
323 		|| (enc_dbcs != 0
324 		    && MB_BYTE2LEN(ScreenLines[off_from]) > 1
325 		    && (enc_dbcs == DBCS_JPNU && ScreenLines[off_from] == 0x8e
326 			? ScreenLines2[off_from] != ScreenLines2[off_to]
327 			: (cols > 1 && ScreenLines[off_from + 1]
328 						 != ScreenLines[off_to + 1])))
329 		|| (enc_utf8
330 		    && (ScreenLinesUC[off_from] != ScreenLinesUC[off_to]
331 			|| (ScreenLinesUC[off_from] != 0
332 			    && comp_char_differs(off_from, off_to))
333 			|| ((*mb_off2cells)(off_from, off_from + cols) > 1
334 			    && ScreenLines[off_from + 1]
335 						!= ScreenLines[off_to + 1])))))
336 	return TRUE;
337     return FALSE;
338 }
339 
340 #if defined(FEAT_TERMINAL) || defined(PROTO)
341 /*
342  * Return the index in ScreenLines[] for the current screen line.
343  */
344     int
345 screen_get_current_line_off()
346 {
347     return (int)(current_ScreenLine - ScreenLines);
348 }
349 #endif
350 
351 #ifdef FEAT_PROP_POPUP
352 /*
353  * Return TRUE if this position has a higher level popup or this cell is
354  * transparent in the current popup.
355  */
356     static int
357 blocked_by_popup(int row, int col)
358 {
359     int off;
360 
361     if (!popup_visible)
362 	return FALSE;
363     off = row * screen_Columns + col;
364     return popup_mask[off] > screen_zindex || popup_transparent[off];
365 }
366 #endif
367 
368 /*
369  * Reset the highlighting.  Used before clearing the screen.
370  */
371     void
372 reset_screen_attr(void)
373 {
374 #ifdef FEAT_GUI
375     if (gui.in_use)
376 	// Use a code that will reset gui.highlight_mask in
377 	// gui_stop_highlight().
378 	screen_attr = HL_ALL + 1;
379     else
380 #endif
381 	// Use attributes that is very unlikely to appear in text.
382 	screen_attr = HL_BOLD | HL_UNDERLINE | HL_INVERSE | HL_STRIKETHROUGH;
383 }
384 
385 /*
386  * Move one "cooked" screen line to the screen, but only the characters that
387  * have actually changed.  Handle insert/delete character.
388  * "coloff" gives the first column on the screen for this line.
389  * "endcol" gives the columns where valid characters are.
390  * "clear_width" is the width of the window.  It's > 0 if the rest of the line
391  * needs to be cleared, negative otherwise.
392  * "flags" can have bits:
393  * SLF_POPUP	    popup window
394  * SLF_RIGHTLEFT    rightleft window:
395  *    When TRUE and "clear_width" > 0, clear columns 0 to "endcol"
396  *    When FALSE and "clear_width" > 0, clear columns "endcol" to "clear_width"
397  */
398     void
399 screen_line(
400     int	    row,
401     int	    coloff,
402     int	    endcol,
403     int	    clear_width,
404     int	    flags UNUSED)
405 {
406     unsigned	    off_from;
407     unsigned	    off_to;
408     unsigned	    max_off_from;
409     unsigned	    max_off_to;
410     int		    col = 0;
411     int		    hl;
412     int		    force = FALSE;	// force update rest of the line
413     int		    redraw_this		// bool: does character need redraw?
414 #ifdef FEAT_GUI
415 				= TRUE	// For GUI when while-loop empty
416 #endif
417 				;
418     int		    redraw_next;	// redraw_this for next character
419     int		    clear_next = FALSE;
420     int		    char_cells;		// 1: normal char
421 					// 2: occupies two display cells
422 # define CHAR_CELLS char_cells
423 
424     // Check for illegal row and col, just in case.
425     if (row >= Rows)
426 	row = Rows - 1;
427     if (endcol > Columns)
428 	endcol = Columns;
429 
430 # ifdef FEAT_CLIPBOARD
431     clip_may_clear_selection(row, row);
432 # endif
433 
434     off_from = (unsigned)(current_ScreenLine - ScreenLines);
435     off_to = LineOffset[row] + coloff;
436     max_off_from = off_from + screen_Columns;
437     max_off_to = LineOffset[row] + screen_Columns;
438 
439 #ifdef FEAT_RIGHTLEFT
440     if (flags & SLF_RIGHTLEFT)
441     {
442 	// Clear rest first, because it's left of the text.
443 	if (clear_width > 0)
444 	{
445 	    while (col <= endcol && ScreenLines[off_to] == ' '
446 		    && ScreenAttrs[off_to] == 0
447 				  && (!enc_utf8 || ScreenLinesUC[off_to] == 0))
448 	    {
449 		++off_to;
450 		++col;
451 	    }
452 	    if (col <= endcol)
453 		screen_fill(row, row + 1, col + coloff,
454 					    endcol + coloff + 1, ' ', ' ', 0);
455 	}
456 	col = endcol + 1;
457 	off_to = LineOffset[row] + col + coloff;
458 	off_from += col;
459 	endcol = (clear_width > 0 ? clear_width : -clear_width);
460     }
461 #endif // FEAT_RIGHTLEFT
462 
463 #ifdef FEAT_PROP_POPUP
464     // First char of a popup window may go on top of the right half of a
465     // double-wide character. Clear the left half to avoid it getting the popup
466     // window background color.
467     if (coloff > 0 && ScreenLines[off_to] == 0)
468     {
469 	ScreenLines[off_to - 1] = ' ';
470 	ScreenLinesUC[off_to - 1] = 0;
471 	screen_char(off_to - 1, row, col + coloff - 1);
472     }
473 #endif
474 
475     redraw_next = char_needs_redraw(off_from, off_to, endcol - col);
476 
477     while (col < endcol)
478     {
479 	if (has_mbyte && (col + 1 < endcol))
480 	    char_cells = (*mb_off2cells)(off_from, max_off_from);
481 	else
482 	    char_cells = 1;
483 
484 	redraw_this = redraw_next;
485 	redraw_next = force || char_needs_redraw(off_from + CHAR_CELLS,
486 			      off_to + CHAR_CELLS, endcol - col - CHAR_CELLS);
487 
488 #ifdef FEAT_GUI
489 	// If the next character was bold, then redraw the current character to
490 	// remove any pixels that might have spilt over into us.  This only
491 	// happens in the GUI.
492 	if (redraw_next && gui.in_use)
493 	{
494 	    hl = ScreenAttrs[off_to + CHAR_CELLS];
495 	    if (hl > HL_ALL)
496 		hl = syn_attr2attr(hl);
497 	    if (hl & HL_BOLD)
498 		redraw_this = TRUE;
499 	}
500 #endif
501 #ifdef FEAT_PROP_POPUP
502 	if (blocked_by_popup(row, col + coloff))
503 	    redraw_this = FALSE;
504 #endif
505 	if (redraw_this)
506 	{
507 	    /*
508 	     * Special handling when 'xs' termcap flag set (hpterm):
509 	     * Attributes for characters are stored at the position where the
510 	     * cursor is when writing the highlighting code.  The
511 	     * start-highlighting code must be written with the cursor on the
512 	     * first highlighted character.  The stop-highlighting code must
513 	     * be written with the cursor just after the last highlighted
514 	     * character.
515 	     * Overwriting a character doesn't remove its highlighting.  Need
516 	     * to clear the rest of the line, and force redrawing it
517 	     * completely.
518 	     */
519 	    if (       p_wiv
520 		    && !force
521 #ifdef FEAT_GUI
522 		    && !gui.in_use
523 #endif
524 		    && ScreenAttrs[off_to] != 0
525 		    && ScreenAttrs[off_from] != ScreenAttrs[off_to])
526 	    {
527 		/*
528 		 * Need to remove highlighting attributes here.
529 		 */
530 		windgoto(row, col + coloff);
531 		out_str(T_CE);		// clear rest of this screen line
532 		screen_start();		// don't know where cursor is now
533 		force = TRUE;		// force redraw of rest of the line
534 		redraw_next = TRUE;	// or else next char would miss out
535 
536 		/*
537 		 * If the previous character was highlighted, need to stop
538 		 * highlighting at this character.
539 		 */
540 		if (col + coloff > 0 && ScreenAttrs[off_to - 1] != 0)
541 		{
542 		    screen_attr = ScreenAttrs[off_to - 1];
543 		    term_windgoto(row, col + coloff);
544 		    screen_stop_highlight();
545 		}
546 		else
547 		    screen_attr = 0;	    // highlighting has stopped
548 	    }
549 	    if (enc_dbcs != 0)
550 	    {
551 		// Check if overwriting a double-byte with a single-byte or
552 		// the other way around requires another character to be
553 		// redrawn.  For UTF-8 this isn't needed, because comparing
554 		// ScreenLinesUC[] is sufficient.
555 		if (char_cells == 1
556 			&& col + 1 < endcol
557 			&& (*mb_off2cells)(off_to, max_off_to) > 1)
558 		{
559 		    // Writing a single-cell character over a double-cell
560 		    // character: need to redraw the next cell.
561 		    ScreenLines[off_to + 1] = 0;
562 		    redraw_next = TRUE;
563 		}
564 		else if (char_cells == 2
565 			&& col + 2 < endcol
566 			&& (*mb_off2cells)(off_to, max_off_to) == 1
567 			&& (*mb_off2cells)(off_to + 1, max_off_to) > 1)
568 		{
569 		    // Writing the second half of a double-cell character over
570 		    // a double-cell character: need to redraw the second
571 		    // cell.
572 		    ScreenLines[off_to + 2] = 0;
573 		    redraw_next = TRUE;
574 		}
575 
576 		if (enc_dbcs == DBCS_JPNU)
577 		    ScreenLines2[off_to] = ScreenLines2[off_from];
578 	    }
579 	    // When writing a single-width character over a double-width
580 	    // character and at the end of the redrawn text, need to clear out
581 	    // the right halve of the old character.
582 	    // Also required when writing the right halve of a double-width
583 	    // char over the left halve of an existing one.
584 	    if (has_mbyte && col + char_cells == endcol
585 		    && ((char_cells == 1
586 			    && (*mb_off2cells)(off_to, max_off_to) > 1)
587 			|| (char_cells == 2
588 			    && (*mb_off2cells)(off_to, max_off_to) == 1
589 			    && (*mb_off2cells)(off_to + 1, max_off_to) > 1)))
590 		clear_next = TRUE;
591 
592 	    ScreenLines[off_to] = ScreenLines[off_from];
593 	    if (enc_utf8)
594 	    {
595 		ScreenLinesUC[off_to] = ScreenLinesUC[off_from];
596 		if (ScreenLinesUC[off_from] != 0)
597 		{
598 		    int	    i;
599 
600 		    for (i = 0; i < Screen_mco; ++i)
601 			ScreenLinesC[i][off_to] = ScreenLinesC[i][off_from];
602 		}
603 	    }
604 	    if (char_cells == 2)
605 		ScreenLines[off_to + 1] = ScreenLines[off_from + 1];
606 
607 #if defined(FEAT_GUI) || defined(UNIX)
608 	    // The bold trick makes a single column of pixels appear in the
609 	    // next character.  When a bold character is removed, the next
610 	    // character should be redrawn too.  This happens for our own GUI
611 	    // and for some xterms.
612 	    if (
613 # ifdef FEAT_GUI
614 		    gui.in_use
615 # endif
616 # if defined(FEAT_GUI) && defined(UNIX)
617 		    ||
618 # endif
619 # ifdef UNIX
620 		    term_is_xterm
621 # endif
622 		    )
623 	    {
624 		hl = ScreenAttrs[off_to];
625 		if (hl > HL_ALL)
626 		    hl = syn_attr2attr(hl);
627 		if (hl & HL_BOLD)
628 		    redraw_next = TRUE;
629 	    }
630 #endif
631 	    ScreenAttrs[off_to] = ScreenAttrs[off_from];
632 
633 	    // For simplicity set the attributes of second half of a
634 	    // double-wide character equal to the first half.
635 	    if (char_cells == 2)
636 		ScreenAttrs[off_to + 1] = ScreenAttrs[off_from];
637 
638 	    if (enc_dbcs != 0 && char_cells == 2)
639 		screen_char_2(off_to, row, col + coloff);
640 	    else
641 		screen_char(off_to, row, col + coloff);
642 	}
643 	else if (  p_wiv
644 #ifdef FEAT_GUI
645 		&& !gui.in_use
646 #endif
647 		&& col + coloff > 0)
648 	{
649 	    if (ScreenAttrs[off_to] == ScreenAttrs[off_to - 1])
650 	    {
651 		/*
652 		 * Don't output stop-highlight when moving the cursor, it will
653 		 * stop the highlighting when it should continue.
654 		 */
655 		screen_attr = 0;
656 	    }
657 	    else if (screen_attr != 0)
658 		screen_stop_highlight();
659 	}
660 
661 	off_to += CHAR_CELLS;
662 	off_from += CHAR_CELLS;
663 	col += CHAR_CELLS;
664     }
665 
666     if (clear_next)
667     {
668 	// Clear the second half of a double-wide character of which the left
669 	// half was overwritten with a single-wide character.
670 	ScreenLines[off_to] = ' ';
671 	if (enc_utf8)
672 	    ScreenLinesUC[off_to] = 0;
673 	screen_char(off_to, row, col + coloff);
674     }
675 
676     if (clear_width > 0
677 #ifdef FEAT_RIGHTLEFT
678 		    && !(flags & SLF_RIGHTLEFT)
679 #endif
680 				   )
681     {
682 #ifdef FEAT_GUI
683 	int startCol = col;
684 #endif
685 
686 	// blank out the rest of the line
687 	while (col < clear_width && ScreenLines[off_to] == ' '
688 						  && ScreenAttrs[off_to] == 0
689 				  && (!enc_utf8 || ScreenLinesUC[off_to] == 0))
690 	{
691 	    ++off_to;
692 	    ++col;
693 	}
694 	if (col < clear_width)
695 	{
696 #ifdef FEAT_GUI
697 	    /*
698 	     * In the GUI, clearing the rest of the line may leave pixels
699 	     * behind if the first character cleared was bold.  Some bold
700 	     * fonts spill over the left.  In this case we redraw the previous
701 	     * character too.  If we didn't skip any blanks above, then we
702 	     * only redraw if the character wasn't already redrawn anyway.
703 	     */
704 	    if (gui.in_use && (col > startCol || !redraw_this))
705 	    {
706 		hl = ScreenAttrs[off_to];
707 		if (hl > HL_ALL || (hl & HL_BOLD))
708 		{
709 		    int prev_cells = 1;
710 
711 		    if (enc_utf8)
712 			// for utf-8, ScreenLines[char_offset + 1] == 0 means
713 			// that its width is 2.
714 			prev_cells = ScreenLines[off_to - 1] == 0 ? 2 : 1;
715 		    else if (enc_dbcs != 0)
716 		    {
717 			// find previous character by counting from first
718 			// column and get its width.
719 			unsigned off = LineOffset[row];
720 			unsigned max_off = LineOffset[row] + screen_Columns;
721 
722 			while (off < off_to)
723 			{
724 			    prev_cells = (*mb_off2cells)(off, max_off);
725 			    off += prev_cells;
726 			}
727 		    }
728 
729 		    if (enc_dbcs != 0 && prev_cells > 1)
730 			screen_char_2(off_to - prev_cells, row,
731 						   col + coloff - prev_cells);
732 		    else
733 			screen_char(off_to - prev_cells, row,
734 						   col + coloff - prev_cells);
735 		}
736 	    }
737 #endif
738 	    screen_fill(row, row + 1, col + coloff, clear_width + coloff,
739 								 ' ', ' ', 0);
740 	    off_to += clear_width - col;
741 	    col = clear_width;
742 	}
743     }
744 
745     if (clear_width > 0
746 #ifdef FEAT_PROP_POPUP
747 	    && !(flags & SLF_POPUP)  // no separator for popup window
748 #endif
749 	    )
750     {
751 	// For a window that has a right neighbor, draw the separator char
752 	// right of the window contents.  But not on top of a popup window.
753 	if (coloff + col < Columns)
754 	{
755 #ifdef FEAT_PROP_POPUP
756 	    if (!blocked_by_popup(row, col + coloff))
757 #endif
758 	    {
759 		int c;
760 
761 		c = fillchar_vsep(&hl);
762 		if (ScreenLines[off_to] != (schar_T)c
763 			|| (enc_utf8 && (int)ScreenLinesUC[off_to]
764 							!= (c >= 0x80 ? c : 0))
765 			|| ScreenAttrs[off_to] != hl)
766 		{
767 		    ScreenLines[off_to] = c;
768 		    ScreenAttrs[off_to] = hl;
769 		    if (enc_utf8)
770 		    {
771 			if (c >= 0x80)
772 			{
773 			    ScreenLinesUC[off_to] = c;
774 			    ScreenLinesC[0][off_to] = 0;
775 			}
776 			else
777 			    ScreenLinesUC[off_to] = 0;
778 		    }
779 		    screen_char(off_to, row, col + coloff);
780 		}
781 	    }
782 	}
783 	else
784 	    LineWraps[row] = FALSE;
785     }
786 }
787 
788 #if defined(FEAT_RIGHTLEFT) || defined(PROTO)
789 /*
790  * Mirror text "str" for right-left displaying.
791  * Only works for single-byte characters (e.g., numbers).
792  */
793     void
794 rl_mirror(char_u *str)
795 {
796     char_u	*p1, *p2;
797     int		t;
798 
799     for (p1 = str, p2 = str + STRLEN(str) - 1; p1 < p2; ++p1, --p2)
800     {
801 	t = *p1;
802 	*p1 = *p2;
803 	*p2 = t;
804     }
805 }
806 #endif
807 
808 /*
809  * Draw the verticap separator right of window "wp" starting with line "row".
810  */
811     void
812 draw_vsep_win(win_T *wp, int row)
813 {
814     int		hl;
815     int		c;
816 
817     if (wp->w_vsep_width)
818     {
819 	// draw the vertical separator right of this window
820 	c = fillchar_vsep(&hl);
821 	screen_fill(W_WINROW(wp) + row, W_WINROW(wp) + wp->w_height,
822 		W_ENDCOL(wp), W_ENDCOL(wp) + 1,
823 		c, ' ', hl);
824     }
825 }
826 
827 #ifdef FEAT_WILDMENU
828 static int skip_status_match_char(expand_T *xp, char_u *s);
829 
830 /*
831  * Get the length of an item as it will be shown in the status line.
832  */
833     static int
834 status_match_len(expand_T *xp, char_u *s)
835 {
836     int	len = 0;
837 
838 #ifdef FEAT_MENU
839     int emenu = (xp->xp_context == EXPAND_MENUS
840 	    || xp->xp_context == EXPAND_MENUNAMES);
841 
842     // Check for menu separators - replace with '|'.
843     if (emenu && menu_is_separator(s))
844 	return 1;
845 #endif
846 
847     while (*s != NUL)
848     {
849 	s += skip_status_match_char(xp, s);
850 	len += ptr2cells(s);
851 	MB_PTR_ADV(s);
852     }
853 
854     return len;
855 }
856 
857 /*
858  * Return the number of characters that should be skipped in a status match.
859  * These are backslashes used for escaping.  Do show backslashes in help tags.
860  */
861     static int
862 skip_status_match_char(expand_T *xp, char_u *s)
863 {
864     if ((rem_backslash(s) && xp->xp_context != EXPAND_HELP)
865 #ifdef FEAT_MENU
866 	    || ((xp->xp_context == EXPAND_MENUS
867 		    || xp->xp_context == EXPAND_MENUNAMES)
868 			  && (s[0] == '\t' || (s[0] == '\\' && s[1] != NUL)))
869 #endif
870 	   )
871     {
872 #ifndef BACKSLASH_IN_FILENAME
873 	if (xp->xp_shell && csh_like_shell() && s[1] == '\\' && s[2] == '!')
874 	    return 2;
875 #endif
876 	return 1;
877     }
878     return 0;
879 }
880 
881 /*
882  * Show wildchar matches in the status line.
883  * Show at least the "match" item.
884  * We start at item 'first_match' in the list and show all matches that fit.
885  *
886  * If inversion is possible we use it. Else '=' characters are used.
887  */
888     void
889 win_redr_status_matches(
890     expand_T	*xp,
891     int		num_matches,
892     char_u	**matches,	// list of matches
893     int		match,
894     int		showtail)
895 {
896 #define L_MATCH(m) (showtail ? sm_gettail(matches[m]) : matches[m])
897     int		row;
898     char_u	*buf;
899     int		len;
900     int		clen;		// length in screen cells
901     int		fillchar;
902     int		attr;
903     int		i;
904     int		highlight = TRUE;
905     char_u	*selstart = NULL;
906     int		selstart_col = 0;
907     char_u	*selend = NULL;
908     static int	first_match = 0;
909     int		add_left = FALSE;
910     char_u	*s;
911 #ifdef FEAT_MENU
912     int		emenu;
913 #endif
914     int		l;
915 
916     if (matches == NULL)	// interrupted completion?
917 	return;
918 
919     if (has_mbyte)
920 	buf = alloc(Columns * MB_MAXBYTES + 1);
921     else
922 	buf = alloc(Columns + 1);
923     if (buf == NULL)
924 	return;
925 
926     if (match == -1)	// don't show match but original text
927     {
928 	match = 0;
929 	highlight = FALSE;
930     }
931     // count 1 for the ending ">"
932     clen = status_match_len(xp, L_MATCH(match)) + 3;
933     if (match == 0)
934 	first_match = 0;
935     else if (match < first_match)
936     {
937 	// jumping left, as far as we can go
938 	first_match = match;
939 	add_left = TRUE;
940     }
941     else
942     {
943 	// check if match fits on the screen
944 	for (i = first_match; i < match; ++i)
945 	    clen += status_match_len(xp, L_MATCH(i)) + 2;
946 	if (first_match > 0)
947 	    clen += 2;
948 	// jumping right, put match at the left
949 	if ((long)clen > Columns)
950 	{
951 	    first_match = match;
952 	    // if showing the last match, we can add some on the left
953 	    clen = 2;
954 	    for (i = match; i < num_matches; ++i)
955 	    {
956 		clen += status_match_len(xp, L_MATCH(i)) + 2;
957 		if ((long)clen >= Columns)
958 		    break;
959 	    }
960 	    if (i == num_matches)
961 		add_left = TRUE;
962 	}
963     }
964     if (add_left)
965 	while (first_match > 0)
966 	{
967 	    clen += status_match_len(xp, L_MATCH(first_match - 1)) + 2;
968 	    if ((long)clen >= Columns)
969 		break;
970 	    --first_match;
971 	}
972 
973     fillchar = fillchar_status(&attr, curwin);
974 
975     if (first_match == 0)
976     {
977 	*buf = NUL;
978 	len = 0;
979     }
980     else
981     {
982 	STRCPY(buf, "< ");
983 	len = 2;
984     }
985     clen = len;
986 
987     i = first_match;
988     while ((long)(clen + status_match_len(xp, L_MATCH(i)) + 2) < Columns)
989     {
990 	if (i == match)
991 	{
992 	    selstart = buf + len;
993 	    selstart_col = clen;
994 	}
995 
996 	s = L_MATCH(i);
997 	// Check for menu separators - replace with '|'
998 #ifdef FEAT_MENU
999 	emenu = (xp->xp_context == EXPAND_MENUS
1000 		|| xp->xp_context == EXPAND_MENUNAMES);
1001 	if (emenu && menu_is_separator(s))
1002 	{
1003 	    STRCPY(buf + len, transchar('|'));
1004 	    l = (int)STRLEN(buf + len);
1005 	    len += l;
1006 	    clen += l;
1007 	}
1008 	else
1009 #endif
1010 	    for ( ; *s != NUL; ++s)
1011 	{
1012 	    s += skip_status_match_char(xp, s);
1013 	    clen += ptr2cells(s);
1014 	    if (has_mbyte && (l = (*mb_ptr2len)(s)) > 1)
1015 	    {
1016 		STRNCPY(buf + len, s, l);
1017 		s += l - 1;
1018 		len += l;
1019 	    }
1020 	    else
1021 	    {
1022 		STRCPY(buf + len, transchar_byte(*s));
1023 		len += (int)STRLEN(buf + len);
1024 	    }
1025 	}
1026 	if (i == match)
1027 	    selend = buf + len;
1028 
1029 	*(buf + len++) = ' ';
1030 	*(buf + len++) = ' ';
1031 	clen += 2;
1032 	if (++i == num_matches)
1033 		break;
1034     }
1035 
1036     if (i != num_matches)
1037     {
1038 	*(buf + len++) = '>';
1039 	++clen;
1040     }
1041 
1042     buf[len] = NUL;
1043 
1044     row = cmdline_row - 1;
1045     if (row >= 0)
1046     {
1047 	if (wild_menu_showing == 0)
1048 	{
1049 	    if (msg_scrolled > 0)
1050 	    {
1051 		// Put the wildmenu just above the command line.  If there is
1052 		// no room, scroll the screen one line up.
1053 		if (cmdline_row == Rows - 1)
1054 		{
1055 		    screen_del_lines(0, 0, 1, (int)Rows, TRUE, 0, NULL);
1056 		    ++msg_scrolled;
1057 		}
1058 		else
1059 		{
1060 		    ++cmdline_row;
1061 		    ++row;
1062 		}
1063 		wild_menu_showing = WM_SCROLLED;
1064 	    }
1065 	    else
1066 	    {
1067 		// Create status line if needed by setting 'laststatus' to 2.
1068 		// Set 'winminheight' to zero to avoid that the window is
1069 		// resized.
1070 		if (lastwin->w_status_height == 0)
1071 		{
1072 		    save_p_ls = p_ls;
1073 		    save_p_wmh = p_wmh;
1074 		    p_ls = 2;
1075 		    p_wmh = 0;
1076 		    last_status(FALSE);
1077 		}
1078 		wild_menu_showing = WM_SHOWN;
1079 	    }
1080 	}
1081 
1082 	screen_puts(buf, row, 0, attr);
1083 	if (selstart != NULL && highlight)
1084 	{
1085 	    *selend = NUL;
1086 	    screen_puts(selstart, row, selstart_col, HL_ATTR(HLF_WM));
1087 	}
1088 
1089 	screen_fill(row, row + 1, clen, (int)Columns, fillchar, fillchar, attr);
1090     }
1091 
1092     win_redraw_last_status(topframe);
1093     vim_free(buf);
1094 }
1095 #endif
1096 
1097 /*
1098  * Return TRUE if the status line of window "wp" is connected to the status
1099  * line of the window right of it.  If not, then it's a vertical separator.
1100  * Only call if (wp->w_vsep_width != 0).
1101  */
1102     int
1103 stl_connected(win_T *wp)
1104 {
1105     frame_T	*fr;
1106 
1107     fr = wp->w_frame;
1108     while (fr->fr_parent != NULL)
1109     {
1110 	if (fr->fr_parent->fr_layout == FR_COL)
1111 	{
1112 	    if (fr->fr_next != NULL)
1113 		break;
1114 	}
1115 	else
1116 	{
1117 	    if (fr->fr_next != NULL)
1118 		return TRUE;
1119 	}
1120 	fr = fr->fr_parent;
1121     }
1122     return FALSE;
1123 }
1124 
1125 
1126 /*
1127  * Get the value to show for the language mappings, active 'keymap'.
1128  */
1129     int
1130 get_keymap_str(
1131     win_T	*wp,
1132     char_u	*fmt,	    // format string containing one %s item
1133     char_u	*buf,	    // buffer for the result
1134     int		len)	    // length of buffer
1135 {
1136     char_u	*p;
1137 
1138     if (wp->w_buffer->b_p_iminsert != B_IMODE_LMAP)
1139 	return FALSE;
1140 
1141     {
1142 #ifdef FEAT_EVAL
1143 	buf_T	*old_curbuf = curbuf;
1144 	win_T	*old_curwin = curwin;
1145 	char_u	*s;
1146 
1147 	curbuf = wp->w_buffer;
1148 	curwin = wp;
1149 	STRCPY(buf, "b:keymap_name");	// must be writable
1150 	++emsg_skip;
1151 	s = p = eval_to_string(buf, NULL, FALSE);
1152 	--emsg_skip;
1153 	curbuf = old_curbuf;
1154 	curwin = old_curwin;
1155 	if (p == NULL || *p == NUL)
1156 #endif
1157 	{
1158 #ifdef FEAT_KEYMAP
1159 	    if (wp->w_buffer->b_kmap_state & KEYMAP_LOADED)
1160 		p = wp->w_buffer->b_p_keymap;
1161 	    else
1162 #endif
1163 		p = (char_u *)"lang";
1164 	}
1165 	if (vim_snprintf((char *)buf, len, (char *)fmt, p) > len - 1)
1166 	    buf[0] = NUL;
1167 #ifdef FEAT_EVAL
1168 	vim_free(s);
1169 #endif
1170     }
1171     return buf[0] != NUL;
1172 }
1173 
1174 #if defined(FEAT_STL_OPT) || defined(PROTO)
1175 /*
1176  * Redraw the status line or ruler of window "wp".
1177  * When "wp" is NULL redraw the tab pages line from 'tabline'.
1178  */
1179     void
1180 win_redr_custom(
1181     win_T	*wp,
1182     int		draw_ruler)	// TRUE or FALSE
1183 {
1184     static int	entered = FALSE;
1185     int		attr;
1186     int		curattr;
1187     int		row;
1188     int		col = 0;
1189     int		maxwidth;
1190     int		width;
1191     int		n;
1192     int		len;
1193     int		fillchar;
1194     char_u	buf[MAXPATHL];
1195     char_u	*stl;
1196     char_u	*p;
1197     struct	stl_hlrec hltab[STL_MAX_ITEM];
1198     struct	stl_hlrec tabtab[STL_MAX_ITEM];
1199     int		use_sandbox = FALSE;
1200     win_T	*ewp;
1201     int		p_crb_save;
1202 
1203     // There is a tiny chance that this gets called recursively: When
1204     // redrawing a status line triggers redrawing the ruler or tabline.
1205     // Avoid trouble by not allowing recursion.
1206     if (entered)
1207 	return;
1208     entered = TRUE;
1209 
1210     // setup environment for the task at hand
1211     if (wp == NULL)
1212     {
1213 	// Use 'tabline'.  Always at the first line of the screen.
1214 	stl = p_tal;
1215 	row = 0;
1216 	fillchar = ' ';
1217 	attr = HL_ATTR(HLF_TPF);
1218 	maxwidth = Columns;
1219 # ifdef FEAT_EVAL
1220 	use_sandbox = was_set_insecurely((char_u *)"tabline", 0);
1221 # endif
1222     }
1223     else
1224     {
1225 	row = W_WINROW(wp) + wp->w_height;
1226 	fillchar = fillchar_status(&attr, wp);
1227 	maxwidth = wp->w_width;
1228 
1229 	if (draw_ruler)
1230 	{
1231 	    stl = p_ruf;
1232 	    // advance past any leading group spec - implicit in ru_col
1233 	    if (*stl == '%')
1234 	    {
1235 		if (*++stl == '-')
1236 		    stl++;
1237 		if (atoi((char *)stl))
1238 		    while (VIM_ISDIGIT(*stl))
1239 			stl++;
1240 		if (*stl++ != '(')
1241 		    stl = p_ruf;
1242 	    }
1243 	    col = ru_col - (Columns - wp->w_width);
1244 	    if (col < (wp->w_width + 1) / 2)
1245 		col = (wp->w_width + 1) / 2;
1246 	    maxwidth = wp->w_width - col;
1247 	    if (!wp->w_status_height)
1248 	    {
1249 		row = Rows - 1;
1250 		--maxwidth;	// writing in last column may cause scrolling
1251 		fillchar = ' ';
1252 		attr = 0;
1253 	    }
1254 
1255 # ifdef FEAT_EVAL
1256 	    use_sandbox = was_set_insecurely((char_u *)"rulerformat", 0);
1257 # endif
1258 	}
1259 	else
1260 	{
1261 	    if (*wp->w_p_stl != NUL)
1262 		stl = wp->w_p_stl;
1263 	    else
1264 		stl = p_stl;
1265 # ifdef FEAT_EVAL
1266 	    use_sandbox = was_set_insecurely((char_u *)"statusline",
1267 					 *wp->w_p_stl == NUL ? 0 : OPT_LOCAL);
1268 # endif
1269 	}
1270 
1271 	col += wp->w_wincol;
1272     }
1273 
1274     if (maxwidth <= 0)
1275 	goto theend;
1276 
1277     // Temporarily reset 'cursorbind', we don't want a side effect from moving
1278     // the cursor away and back.
1279     ewp = wp == NULL ? curwin : wp;
1280     p_crb_save = ewp->w_p_crb;
1281     ewp->w_p_crb = FALSE;
1282 
1283     // Make a copy, because the statusline may include a function call that
1284     // might change the option value and free the memory.
1285     stl = vim_strsave(stl);
1286     width = build_stl_str_hl(ewp, buf, sizeof(buf),
1287 				stl, use_sandbox,
1288 				fillchar, maxwidth, hltab, tabtab);
1289     vim_free(stl);
1290     ewp->w_p_crb = p_crb_save;
1291 
1292     // Make all characters printable.
1293     p = transstr(buf);
1294     if (p != NULL)
1295     {
1296 	vim_strncpy(buf, p, sizeof(buf) - 1);
1297 	vim_free(p);
1298     }
1299 
1300     // fill up with "fillchar"
1301     len = (int)STRLEN(buf);
1302     while (width < maxwidth && len < (int)sizeof(buf) - 1)
1303     {
1304 	len += (*mb_char2bytes)(fillchar, buf + len);
1305 	++width;
1306     }
1307     buf[len] = NUL;
1308 
1309     /*
1310      * Draw each snippet with the specified highlighting.
1311      */
1312     curattr = attr;
1313     p = buf;
1314     for (n = 0; hltab[n].start != NULL; n++)
1315     {
1316 	len = (int)(hltab[n].start - p);
1317 	screen_puts_len(p, len, row, col, curattr);
1318 	col += vim_strnsize(p, len);
1319 	p = hltab[n].start;
1320 
1321 	if (hltab[n].userhl == 0)
1322 	    curattr = attr;
1323 	else if (hltab[n].userhl < 0)
1324 	    curattr = syn_id2attr(-hltab[n].userhl);
1325 #ifdef FEAT_TERMINAL
1326 	else if (wp != NULL && wp != curwin && bt_terminal(wp->w_buffer)
1327 						   && wp->w_status_height != 0)
1328 	    curattr = highlight_stltermnc[hltab[n].userhl - 1];
1329 	else if (wp != NULL && bt_terminal(wp->w_buffer)
1330 						   && wp->w_status_height != 0)
1331 	    curattr = highlight_stlterm[hltab[n].userhl - 1];
1332 #endif
1333 	else if (wp != NULL && wp != curwin && wp->w_status_height != 0)
1334 	    curattr = highlight_stlnc[hltab[n].userhl - 1];
1335 	else
1336 	    curattr = highlight_user[hltab[n].userhl - 1];
1337     }
1338     screen_puts(p, row, col, curattr);
1339 
1340     if (wp == NULL)
1341     {
1342 	// Fill the TabPageIdxs[] array for clicking in the tab pagesline.
1343 	col = 0;
1344 	len = 0;
1345 	p = buf;
1346 	fillchar = 0;
1347 	for (n = 0; tabtab[n].start != NULL; n++)
1348 	{
1349 	    len += vim_strnsize(p, (int)(tabtab[n].start - p));
1350 	    while (col < len)
1351 		TabPageIdxs[col++] = fillchar;
1352 	    p = tabtab[n].start;
1353 	    fillchar = tabtab[n].userhl;
1354 	}
1355 	while (col < Columns)
1356 	    TabPageIdxs[col++] = fillchar;
1357     }
1358 
1359 theend:
1360     entered = FALSE;
1361 }
1362 
1363 #endif // FEAT_STL_OPT
1364 
1365 /*
1366  * Output a single character directly to the screen and update ScreenLines.
1367  */
1368     void
1369 screen_putchar(int c, int row, int col, int attr)
1370 {
1371     char_u	buf[MB_MAXBYTES + 1];
1372 
1373     if (has_mbyte)
1374 	buf[(*mb_char2bytes)(c, buf)] = NUL;
1375     else
1376     {
1377 	buf[0] = c;
1378 	buf[1] = NUL;
1379     }
1380     screen_puts(buf, row, col, attr);
1381 }
1382 
1383 /*
1384  * Get a single character directly from ScreenLines into "bytes[]".
1385  * Also return its attribute in *attrp;
1386  */
1387     void
1388 screen_getbytes(int row, int col, char_u *bytes, int *attrp)
1389 {
1390     unsigned off;
1391 
1392     // safety check
1393     if (ScreenLines != NULL && row < screen_Rows && col < screen_Columns)
1394     {
1395 	off = LineOffset[row] + col;
1396 	*attrp = ScreenAttrs[off];
1397 	bytes[0] = ScreenLines[off];
1398 	bytes[1] = NUL;
1399 
1400 	if (enc_utf8 && ScreenLinesUC[off] != 0)
1401 	    bytes[utfc_char2bytes(off, bytes)] = NUL;
1402 	else if (enc_dbcs == DBCS_JPNU && ScreenLines[off] == 0x8e)
1403 	{
1404 	    bytes[0] = ScreenLines[off];
1405 	    bytes[1] = ScreenLines2[off];
1406 	    bytes[2] = NUL;
1407 	}
1408 	else if (enc_dbcs && MB_BYTE2LEN(bytes[0]) > 1)
1409 	{
1410 	    bytes[1] = ScreenLines[off + 1];
1411 	    bytes[2] = NUL;
1412 	}
1413     }
1414 }
1415 
1416 /*
1417  * Return TRUE if composing characters for screen posn "off" differs from
1418  * composing characters in "u8cc".
1419  * Only to be used when ScreenLinesUC[off] != 0.
1420  */
1421     static int
1422 screen_comp_differs(int off, int *u8cc)
1423 {
1424     int	    i;
1425 
1426     for (i = 0; i < Screen_mco; ++i)
1427     {
1428 	if (ScreenLinesC[i][off] != (u8char_T)u8cc[i])
1429 	    return TRUE;
1430 	if (u8cc[i] == 0)
1431 	    break;
1432     }
1433     return FALSE;
1434 }
1435 
1436 /*
1437  * Put string '*text' on the screen at position 'row' and 'col', with
1438  * attributes 'attr', and update ScreenLines[] and ScreenAttrs[].
1439  * Note: only outputs within one row, message is truncated at screen boundary!
1440  * Note: if ScreenLines[], row and/or col is invalid, nothing is done.
1441  */
1442     void
1443 screen_puts(
1444     char_u	*text,
1445     int		row,
1446     int		col,
1447     int		attr)
1448 {
1449     screen_puts_len(text, -1, row, col, attr);
1450 }
1451 
1452 /*
1453  * Like screen_puts(), but output "text[len]".  When "len" is -1 output up to
1454  * a NUL.
1455  */
1456     void
1457 screen_puts_len(
1458     char_u	*text,
1459     int		textlen,
1460     int		row,
1461     int		col,
1462     int		attr)
1463 {
1464     unsigned	off;
1465     char_u	*ptr = text;
1466     int		len = textlen;
1467     int		c;
1468     unsigned	max_off;
1469     int		mbyte_blen = 1;
1470     int		mbyte_cells = 1;
1471     int		u8c = 0;
1472     int		u8cc[MAX_MCO];
1473     int		clear_next_cell = FALSE;
1474 #ifdef FEAT_ARABIC
1475     int		prev_c = 0;		// previous Arabic character
1476     int		pc, nc, nc1;
1477     int		pcc[MAX_MCO];
1478 #endif
1479     int		force_redraw_this;
1480     int		force_redraw_next = FALSE;
1481     int		need_redraw;
1482 
1483     // Safety check. The check for negative row and column is to fix issue
1484     // #4102. TODO: find out why row/col could be negative.
1485     if (ScreenLines == NULL
1486 	    || row >= screen_Rows || row < 0
1487 	    || col >= screen_Columns || col < 0)
1488 	return;
1489     off = LineOffset[row] + col;
1490 
1491     // When drawing over the right halve of a double-wide char clear out the
1492     // left halve.  Only needed in a terminal.
1493     if (has_mbyte && col > 0 && col < screen_Columns
1494 #ifdef FEAT_GUI
1495 	    && !gui.in_use
1496 #endif
1497 	    && mb_fix_col(col, row) != col)
1498     {
1499 	ScreenLines[off - 1] = ' ';
1500 	ScreenAttrs[off - 1] = 0;
1501 	if (enc_utf8)
1502 	{
1503 	    ScreenLinesUC[off - 1] = 0;
1504 	    ScreenLinesC[0][off - 1] = 0;
1505 	}
1506 	// redraw the previous cell, make it empty
1507 	screen_char(off - 1, row, col - 1);
1508 	// force the cell at "col" to be redrawn
1509 	force_redraw_next = TRUE;
1510     }
1511 
1512     max_off = LineOffset[row] + screen_Columns;
1513     while (col < screen_Columns
1514 	    && (len < 0 || (int)(ptr - text) < len)
1515 	    && *ptr != NUL)
1516     {
1517 	c = *ptr;
1518 	// check if this is the first byte of a multibyte
1519 	if (has_mbyte)
1520 	{
1521 	    if (enc_utf8 && len > 0)
1522 		mbyte_blen = utfc_ptr2len_len(ptr, (int)((text + len) - ptr));
1523 	    else
1524 		mbyte_blen = (*mb_ptr2len)(ptr);
1525 	    if (enc_dbcs == DBCS_JPNU && c == 0x8e)
1526 		mbyte_cells = 1;
1527 	    else if (enc_dbcs != 0)
1528 		mbyte_cells = mbyte_blen;
1529 	    else	// enc_utf8
1530 	    {
1531 		if (len >= 0)
1532 		    u8c = utfc_ptr2char_len(ptr, u8cc,
1533 						   (int)((text + len) - ptr));
1534 		else
1535 		    u8c = utfc_ptr2char(ptr, u8cc);
1536 		mbyte_cells = utf_char2cells(u8c);
1537 #ifdef FEAT_ARABIC
1538 		if (p_arshape && !p_tbidi && ARABIC_CHAR(u8c))
1539 		{
1540 		    // Do Arabic shaping.
1541 		    if (len >= 0 && (int)(ptr - text) + mbyte_blen >= len)
1542 		    {
1543 			// Past end of string to be displayed.
1544 			nc = NUL;
1545 			nc1 = NUL;
1546 		    }
1547 		    else
1548 		    {
1549 			nc = utfc_ptr2char_len(ptr + mbyte_blen, pcc,
1550 				      (int)((text + len) - ptr - mbyte_blen));
1551 			nc1 = pcc[0];
1552 		    }
1553 		    pc = prev_c;
1554 		    prev_c = u8c;
1555 		    u8c = arabic_shape(u8c, &c, &u8cc[0], nc, nc1, pc);
1556 		}
1557 		else
1558 		    prev_c = u8c;
1559 #endif
1560 		if (col + mbyte_cells > screen_Columns)
1561 		{
1562 		    // Only 1 cell left, but character requires 2 cells:
1563 		    // display a '>' in the last column to avoid wrapping.
1564 		    c = '>';
1565 		    mbyte_cells = 1;
1566 		}
1567 	    }
1568 	}
1569 
1570 	force_redraw_this = force_redraw_next;
1571 	force_redraw_next = FALSE;
1572 
1573 	need_redraw = ScreenLines[off] != c
1574 		|| (mbyte_cells == 2
1575 		    && ScreenLines[off + 1] != (enc_dbcs ? ptr[1] : 0))
1576 		|| (enc_dbcs == DBCS_JPNU
1577 		    && c == 0x8e
1578 		    && ScreenLines2[off] != ptr[1])
1579 		|| (enc_utf8
1580 		    && (ScreenLinesUC[off] !=
1581 				(u8char_T)(c < 0x80 && u8cc[0] == 0 ? 0 : u8c)
1582 			|| (ScreenLinesUC[off] != 0
1583 					  && screen_comp_differs(off, u8cc))))
1584 		|| ScreenAttrs[off] != attr
1585 		|| exmode_active;
1586 
1587 	if ((need_redraw || force_redraw_this)
1588 #ifdef FEAT_PROP_POPUP
1589 		&& !blocked_by_popup(row, col)
1590 #endif
1591 	   )
1592 	{
1593 #if defined(FEAT_GUI) || defined(UNIX)
1594 	    // The bold trick makes a single row of pixels appear in the next
1595 	    // character.  When a bold character is removed, the next
1596 	    // character should be redrawn too.  This happens for our own GUI
1597 	    // and for some xterms.
1598 	    if (need_redraw && ScreenLines[off] != ' ' && (
1599 # ifdef FEAT_GUI
1600 		    gui.in_use
1601 # endif
1602 # if defined(FEAT_GUI) && defined(UNIX)
1603 		    ||
1604 # endif
1605 # ifdef UNIX
1606 		    term_is_xterm
1607 # endif
1608 		    ))
1609 	    {
1610 		int	n = ScreenAttrs[off];
1611 
1612 		if (n > HL_ALL)
1613 		    n = syn_attr2attr(n);
1614 		if (n & HL_BOLD)
1615 		    force_redraw_next = TRUE;
1616 	    }
1617 #endif
1618 	    // When at the end of the text and overwriting a two-cell
1619 	    // character with a one-cell character, need to clear the next
1620 	    // cell.  Also when overwriting the left halve of a two-cell char
1621 	    // with the right halve of a two-cell char.  Do this only once
1622 	    // (mb_off2cells() may return 2 on the right halve).
1623 	    if (clear_next_cell)
1624 		clear_next_cell = FALSE;
1625 	    else if (has_mbyte
1626 		    && (len < 0 ? ptr[mbyte_blen] == NUL
1627 					     : ptr + mbyte_blen >= text + len)
1628 		    && ((mbyte_cells == 1 && (*mb_off2cells)(off, max_off) > 1)
1629 			|| (mbyte_cells == 2
1630 			    && (*mb_off2cells)(off, max_off) == 1
1631 			    && (*mb_off2cells)(off + 1, max_off) > 1)))
1632 		clear_next_cell = TRUE;
1633 
1634 	    // Make sure we never leave a second byte of a double-byte behind,
1635 	    // it confuses mb_off2cells().
1636 	    if (enc_dbcs
1637 		    && ((mbyte_cells == 1 && (*mb_off2cells)(off, max_off) > 1)
1638 			|| (mbyte_cells == 2
1639 			    && (*mb_off2cells)(off, max_off) == 1
1640 			    && (*mb_off2cells)(off + 1, max_off) > 1)))
1641 		ScreenLines[off + mbyte_blen] = 0;
1642 	    ScreenLines[off] = c;
1643 	    ScreenAttrs[off] = attr;
1644 	    if (enc_utf8)
1645 	    {
1646 		if (c < 0x80 && u8cc[0] == 0)
1647 		    ScreenLinesUC[off] = 0;
1648 		else
1649 		{
1650 		    int	    i;
1651 
1652 		    ScreenLinesUC[off] = u8c;
1653 		    for (i = 0; i < Screen_mco; ++i)
1654 		    {
1655 			ScreenLinesC[i][off] = u8cc[i];
1656 			if (u8cc[i] == 0)
1657 			    break;
1658 		    }
1659 		}
1660 		if (mbyte_cells == 2)
1661 		{
1662 		    ScreenLines[off + 1] = 0;
1663 		    ScreenAttrs[off + 1] = attr;
1664 		}
1665 		screen_char(off, row, col);
1666 	    }
1667 	    else if (mbyte_cells == 2)
1668 	    {
1669 		ScreenLines[off + 1] = ptr[1];
1670 		ScreenAttrs[off + 1] = attr;
1671 		screen_char_2(off, row, col);
1672 	    }
1673 	    else if (enc_dbcs == DBCS_JPNU && c == 0x8e)
1674 	    {
1675 		ScreenLines2[off] = ptr[1];
1676 		screen_char(off, row, col);
1677 	    }
1678 	    else
1679 		screen_char(off, row, col);
1680 	}
1681 	if (has_mbyte)
1682 	{
1683 	    off += mbyte_cells;
1684 	    col += mbyte_cells;
1685 	    ptr += mbyte_blen;
1686 	    if (clear_next_cell)
1687 	    {
1688 		// This only happens at the end, display one space next.
1689 		ptr = (char_u *)" ";
1690 		len = -1;
1691 	    }
1692 	}
1693 	else
1694 	{
1695 	    ++off;
1696 	    ++col;
1697 	    ++ptr;
1698 	}
1699     }
1700 
1701     // If we detected the next character needs to be redrawn, but the text
1702     // doesn't extend up to there, update the character here.
1703     if (force_redraw_next && col < screen_Columns)
1704     {
1705 	if (enc_dbcs != 0 && dbcs_off2cells(off, max_off) > 1)
1706 	    screen_char_2(off, row, col);
1707 	else
1708 	    screen_char(off, row, col);
1709     }
1710 }
1711 
1712 #if defined(FEAT_SEARCH_EXTRA) || defined(PROTO)
1713 /*
1714  * Prepare for 'hlsearch' highlighting.
1715  */
1716     void
1717 start_search_hl(void)
1718 {
1719     if (p_hls && !no_hlsearch)
1720     {
1721 	last_pat_prog(&screen_search_hl.rm);
1722 	screen_search_hl.attr = HL_ATTR(HLF_L);
1723 # ifdef FEAT_RELTIME
1724 	// Set the time limit to 'redrawtime'.
1725 	profile_setlimit(p_rdt, &screen_search_hl.tm);
1726 # endif
1727     }
1728 }
1729 
1730 /*
1731  * Clean up for 'hlsearch' highlighting.
1732  */
1733     void
1734 end_search_hl(void)
1735 {
1736     if (screen_search_hl.rm.regprog != NULL)
1737     {
1738 	vim_regfree(screen_search_hl.rm.regprog);
1739 	screen_search_hl.rm.regprog = NULL;
1740     }
1741 }
1742 #endif
1743 
1744       static void
1745 screen_start_highlight(int attr)
1746 {
1747     attrentry_T *aep = NULL;
1748 
1749     screen_attr = attr;
1750     if (full_screen
1751 #ifdef MSWIN
1752 		    && termcap_active
1753 #endif
1754 				       )
1755     {
1756 #ifdef FEAT_GUI
1757 	if (gui.in_use)
1758 	{
1759 	    char	buf[20];
1760 
1761 	    // The GUI handles this internally.
1762 	    sprintf(buf, IF_EB("\033|%dh", ESC_STR "|%dh"), attr);
1763 	    OUT_STR(buf);
1764 	}
1765 	else
1766 #endif
1767 	{
1768 	    if (attr > HL_ALL)				// special HL attr.
1769 	    {
1770 		if (IS_CTERM)
1771 		    aep = syn_cterm_attr2entry(attr);
1772 		else
1773 		    aep = syn_term_attr2entry(attr);
1774 		if (aep == NULL)	    // did ":syntax clear"
1775 		    attr = 0;
1776 		else
1777 		    attr = aep->ae_attr;
1778 	    }
1779 #if defined(FEAT_VTP) && defined(FEAT_TERMGUICOLORS)
1780 	    if (use_vtp())
1781 	    {
1782 		guicolor_T  defguifg, defguibg;
1783 		int	    defctermfg, defctermbg;
1784 
1785 		// If FG and BG are unset, the color is undefined when
1786 		// BOLD+INVERSE. Use Normal as the default value.
1787 		get_default_console_color(&defctermfg, &defctermbg, &defguifg,
1788 								    &defguibg);
1789 
1790 		if (p_tgc)
1791 		{
1792 		    if (aep == NULL || COLOR_INVALID(aep->ae_u.cterm.fg_rgb))
1793 			term_fg_rgb_color(defguifg);
1794 		    if (aep == NULL || COLOR_INVALID(aep->ae_u.cterm.bg_rgb))
1795 			term_bg_rgb_color(defguibg);
1796 		}
1797 		else if (t_colors >= 256)
1798 		{
1799 		    if (aep == NULL || aep->ae_u.cterm.fg_color == 0)
1800 			term_fg_color(defctermfg);
1801 		    if (aep == NULL || aep->ae_u.cterm.bg_color == 0)
1802 			term_bg_color(defctermbg);
1803 		}
1804 	    }
1805 #endif
1806 	    if ((attr & HL_BOLD) && *T_MD != NUL)	// bold
1807 		out_str(T_MD);
1808 	    else if (aep != NULL && cterm_normal_fg_bold && (
1809 #ifdef FEAT_TERMGUICOLORS
1810 			p_tgc && aep->ae_u.cterm.fg_rgb != CTERMCOLOR
1811 			  ? aep->ae_u.cterm.fg_rgb != INVALCOLOR
1812 			  :
1813 #endif
1814 			    t_colors > 1 && aep->ae_u.cterm.fg_color))
1815 		// If the Normal FG color has BOLD attribute and the new HL
1816 		// has a FG color defined, clear BOLD.
1817 		out_str(T_ME);
1818 	    if ((attr & HL_STANDOUT) && *T_SO != NUL)	// standout
1819 		out_str(T_SO);
1820 	    if ((attr & HL_UNDERCURL) && *T_UCS != NUL) // undercurl
1821 		out_str(T_UCS);
1822 	    if (((attr & HL_UNDERLINE)	    // underline or undercurl
1823 			|| ((attr & HL_UNDERCURL) && *T_UCS == NUL))
1824 		    && *T_US != NUL)
1825 		out_str(T_US);
1826 	    if ((attr & HL_ITALIC) && *T_CZH != NUL)	// italic
1827 		out_str(T_CZH);
1828 	    if ((attr & HL_INVERSE) && *T_MR != NUL)	// inverse (reverse)
1829 		out_str(T_MR);
1830 	    if ((attr & HL_STRIKETHROUGH) && *T_STS != NUL)	// strike
1831 		out_str(T_STS);
1832 
1833 	    /*
1834 	     * Output the color or start string after bold etc., in case the
1835 	     * bold etc. override the color setting.
1836 	     */
1837 	    if (aep != NULL)
1838 	    {
1839 #ifdef FEAT_TERMGUICOLORS
1840 		// When 'termguicolors' is set but fg or bg is unset,
1841 		// fall back to the cterm colors.   This helps for SpellBad,
1842 		// where the GUI uses a red undercurl.
1843 		if (p_tgc && aep->ae_u.cterm.fg_rgb != CTERMCOLOR)
1844 		{
1845 		    if (aep->ae_u.cterm.fg_rgb != INVALCOLOR)
1846 			term_fg_rgb_color(aep->ae_u.cterm.fg_rgb);
1847 		}
1848 		else
1849 #endif
1850 		if (t_colors > 1)
1851 		{
1852 		    if (aep->ae_u.cterm.fg_color)
1853 			term_fg_color(aep->ae_u.cterm.fg_color - 1);
1854 		}
1855 #ifdef FEAT_TERMGUICOLORS
1856 		if (p_tgc && aep->ae_u.cterm.bg_rgb != CTERMCOLOR)
1857 		{
1858 		    if (aep->ae_u.cterm.bg_rgb != INVALCOLOR)
1859 			term_bg_rgb_color(aep->ae_u.cterm.bg_rgb);
1860 		}
1861 		else
1862 #endif
1863 		if (t_colors > 1)
1864 		{
1865 		    if (aep->ae_u.cterm.bg_color)
1866 			term_bg_color(aep->ae_u.cterm.bg_color - 1);
1867 		}
1868 
1869 		if (!IS_CTERM)
1870 		{
1871 		    if (aep->ae_u.term.start != NULL)
1872 			out_str(aep->ae_u.term.start);
1873 		}
1874 	    }
1875 	}
1876     }
1877 }
1878 
1879       void
1880 screen_stop_highlight(void)
1881 {
1882     int	    do_ME = FALSE;	    // output T_ME code
1883 
1884     if (screen_attr != 0
1885 #ifdef MSWIN
1886 			&& termcap_active
1887 #endif
1888 					   )
1889     {
1890 #ifdef FEAT_GUI
1891 	if (gui.in_use)
1892 	{
1893 	    char	buf[20];
1894 
1895 	    // use internal GUI code
1896 	    sprintf(buf, IF_EB("\033|%dH", ESC_STR "|%dH"), screen_attr);
1897 	    OUT_STR(buf);
1898 	}
1899 	else
1900 #endif
1901 	{
1902 	    if (screen_attr > HL_ALL)			// special HL attr.
1903 	    {
1904 		attrentry_T *aep;
1905 
1906 		if (IS_CTERM)
1907 		{
1908 		    /*
1909 		     * Assume that t_me restores the original colors!
1910 		     */
1911 		    aep = syn_cterm_attr2entry(screen_attr);
1912 		    if (aep != NULL && ((
1913 #ifdef FEAT_TERMGUICOLORS
1914 			    p_tgc && aep->ae_u.cterm.fg_rgb != CTERMCOLOR
1915 				? aep->ae_u.cterm.fg_rgb != INVALCOLOR
1916 				:
1917 #endif
1918 				aep->ae_u.cterm.fg_color) || (
1919 #ifdef FEAT_TERMGUICOLORS
1920 			    p_tgc && aep->ae_u.cterm.bg_rgb != CTERMCOLOR
1921 				? aep->ae_u.cterm.bg_rgb != INVALCOLOR
1922 				:
1923 #endif
1924 				aep->ae_u.cterm.bg_color)))
1925 			do_ME = TRUE;
1926 		}
1927 		else
1928 		{
1929 		    aep = syn_term_attr2entry(screen_attr);
1930 		    if (aep != NULL && aep->ae_u.term.stop != NULL)
1931 		    {
1932 			if (STRCMP(aep->ae_u.term.stop, T_ME) == 0)
1933 			    do_ME = TRUE;
1934 			else
1935 			    out_str(aep->ae_u.term.stop);
1936 		    }
1937 		}
1938 		if (aep == NULL)	    // did ":syntax clear"
1939 		    screen_attr = 0;
1940 		else
1941 		    screen_attr = aep->ae_attr;
1942 	    }
1943 
1944 	    /*
1945 	     * Often all ending-codes are equal to T_ME.  Avoid outputting the
1946 	     * same sequence several times.
1947 	     */
1948 	    if (screen_attr & HL_STANDOUT)
1949 	    {
1950 		if (STRCMP(T_SE, T_ME) == 0)
1951 		    do_ME = TRUE;
1952 		else
1953 		    out_str(T_SE);
1954 	    }
1955 	    if ((screen_attr & HL_UNDERCURL) && *T_UCE != NUL)
1956 	    {
1957 		if (STRCMP(T_UCE, T_ME) == 0)
1958 		    do_ME = TRUE;
1959 		else
1960 		    out_str(T_UCE);
1961 	    }
1962 	    if ((screen_attr & HL_UNDERLINE)
1963 			    || ((screen_attr & HL_UNDERCURL) && *T_UCE == NUL))
1964 	    {
1965 		if (STRCMP(T_UE, T_ME) == 0)
1966 		    do_ME = TRUE;
1967 		else
1968 		    out_str(T_UE);
1969 	    }
1970 	    if (screen_attr & HL_ITALIC)
1971 	    {
1972 		if (STRCMP(T_CZR, T_ME) == 0)
1973 		    do_ME = TRUE;
1974 		else
1975 		    out_str(T_CZR);
1976 	    }
1977 	    if (screen_attr & HL_STRIKETHROUGH)
1978 	    {
1979 		if (STRCMP(T_STE, T_ME) == 0)
1980 		    do_ME = TRUE;
1981 		else
1982 		    out_str(T_STE);
1983 	    }
1984 	    if (do_ME || (screen_attr & (HL_BOLD | HL_INVERSE)))
1985 		out_str(T_ME);
1986 
1987 #ifdef FEAT_TERMGUICOLORS
1988 	    if (p_tgc)
1989 	    {
1990 		if (cterm_normal_fg_gui_color != INVALCOLOR)
1991 		    term_fg_rgb_color(cterm_normal_fg_gui_color);
1992 		if (cterm_normal_bg_gui_color != INVALCOLOR)
1993 		    term_bg_rgb_color(cterm_normal_bg_gui_color);
1994 	    }
1995 	    else
1996 #endif
1997 	    {
1998 		if (t_colors > 1)
1999 		{
2000 		    // set Normal cterm colors
2001 		    if (cterm_normal_fg_color != 0)
2002 			term_fg_color(cterm_normal_fg_color - 1);
2003 		    if (cterm_normal_bg_color != 0)
2004 			term_bg_color(cterm_normal_bg_color - 1);
2005 		    if (cterm_normal_fg_bold)
2006 			out_str(T_MD);
2007 		}
2008 	    }
2009 	}
2010     }
2011     screen_attr = 0;
2012 }
2013 
2014 /*
2015  * Reset the colors for a cterm.  Used when leaving Vim.
2016  * The machine specific code may override this again.
2017  */
2018     void
2019 reset_cterm_colors(void)
2020 {
2021     if (IS_CTERM)
2022     {
2023 	// set Normal cterm colors
2024 #ifdef FEAT_TERMGUICOLORS
2025 	if (p_tgc ? (cterm_normal_fg_gui_color != INVALCOLOR
2026 		 || cterm_normal_bg_gui_color != INVALCOLOR)
2027 		: (cterm_normal_fg_color > 0 || cterm_normal_bg_color > 0))
2028 #else
2029 	if (cterm_normal_fg_color > 0 || cterm_normal_bg_color > 0)
2030 #endif
2031 	{
2032 	    out_str(T_OP);
2033 	    screen_attr = -1;
2034 	}
2035 	if (cterm_normal_fg_bold)
2036 	{
2037 	    out_str(T_ME);
2038 	    screen_attr = -1;
2039 	}
2040     }
2041 }
2042 
2043 /*
2044  * Put character ScreenLines["off"] on the screen at position "row" and "col",
2045  * using the attributes from ScreenAttrs["off"].
2046  */
2047     void
2048 screen_char(unsigned off, int row, int col)
2049 {
2050     int		attr;
2051 
2052     // Check for illegal values, just in case (could happen just after
2053     // resizing).
2054     if (row >= screen_Rows || col >= screen_Columns)
2055 	return;
2056 
2057     // Skip if under the popup menu.
2058     // Popup windows with zindex higher than POPUPMENU_ZINDEX go on top.
2059     if (pum_under_menu(row, col)
2060 #ifdef FEAT_PROP_POPUP
2061 	    && screen_zindex <= POPUPMENU_ZINDEX
2062 #endif
2063 	    )
2064 	return;
2065 #ifdef FEAT_PROP_POPUP
2066     if (blocked_by_popup(row, col))
2067 	return;
2068 #endif
2069 
2070     // Outputting a character in the last cell on the screen may scroll the
2071     // screen up.  Only do it when the "xn" termcap property is set, otherwise
2072     // mark the character invalid (update it when scrolled up).
2073     if (*T_XN == NUL
2074 	    && row == screen_Rows - 1 && col == screen_Columns - 1
2075 #ifdef FEAT_RIGHTLEFT
2076 	    // account for first command-line character in rightleft mode
2077 	    && !cmdmsg_rl
2078 #endif
2079        )
2080     {
2081 	ScreenAttrs[off] = (sattr_T)-1;
2082 	return;
2083     }
2084 
2085     /*
2086      * Stop highlighting first, so it's easier to move the cursor.
2087      */
2088     if (screen_char_attr != 0)
2089 	attr = screen_char_attr;
2090     else
2091 	attr = ScreenAttrs[off];
2092     if (screen_attr != attr)
2093 	screen_stop_highlight();
2094 
2095     windgoto(row, col);
2096 
2097     if (screen_attr != attr)
2098 	screen_start_highlight(attr);
2099 
2100     if (enc_utf8 && ScreenLinesUC[off] != 0)
2101     {
2102 	char_u	    buf[MB_MAXBYTES + 1];
2103 
2104 	if (utf_ambiguous_width(ScreenLinesUC[off]))
2105 	{
2106 	    if (*p_ambw == 'd'
2107 #ifdef FEAT_GUI
2108 		    && !gui.in_use
2109 #endif
2110 		    )
2111 	    {
2112 		// Clear the two screen cells. If the character is actually
2113 		// single width it won't change the second cell.
2114 		out_str((char_u *)"  ");
2115 		term_windgoto(row, col);
2116 	    }
2117 	    // not sure where the cursor is after drawing the ambiguous width
2118 	    // character
2119 	    screen_cur_col = 9999;
2120 	}
2121 	else if (utf_char2cells(ScreenLinesUC[off]) > 1)
2122 	    ++screen_cur_col;
2123 
2124 	// Convert the UTF-8 character to bytes and write it.
2125 	buf[utfc_char2bytes(off, buf)] = NUL;
2126 	out_str(buf);
2127     }
2128     else
2129     {
2130 	out_flush_check();
2131 	out_char(ScreenLines[off]);
2132 	// double-byte character in single-width cell
2133 	if (enc_dbcs == DBCS_JPNU && ScreenLines[off] == 0x8e)
2134 	    out_char(ScreenLines2[off]);
2135     }
2136 
2137     screen_cur_col++;
2138 }
2139 
2140 /*
2141  * Used for enc_dbcs only: Put one double-wide character at ScreenLines["off"]
2142  * on the screen at position 'row' and 'col'.
2143  * The attributes of the first byte is used for all.  This is required to
2144  * output the two bytes of a double-byte character with nothing in between.
2145  */
2146     static void
2147 screen_char_2(unsigned off, int row, int col)
2148 {
2149     // Check for illegal values (could be wrong when screen was resized).
2150     if (off + 1 >= (unsigned)(screen_Rows * screen_Columns))
2151 	return;
2152 
2153     // Outputting the last character on the screen may scrollup the screen.
2154     // Don't to it!  Mark the character invalid (update it when scrolled up)
2155     if (row == screen_Rows - 1 && col >= screen_Columns - 2)
2156     {
2157 	ScreenAttrs[off] = (sattr_T)-1;
2158 	return;
2159     }
2160 
2161     // Output the first byte normally (positions the cursor), then write the
2162     // second byte directly.
2163     screen_char(off, row, col);
2164     out_char(ScreenLines[off + 1]);
2165     ++screen_cur_col;
2166 }
2167 
2168 /*
2169  * Draw a rectangle of the screen, inverted when "invert" is TRUE.
2170  * This uses the contents of ScreenLines[] and doesn't change it.
2171  */
2172     void
2173 screen_draw_rectangle(
2174     int		row,
2175     int		col,
2176     int		height,
2177     int		width,
2178     int		invert)
2179 {
2180     int		r, c;
2181     int		off;
2182     int		max_off;
2183 
2184     // Can't use ScreenLines unless initialized
2185     if (ScreenLines == NULL)
2186 	return;
2187 
2188     if (invert)
2189 	screen_char_attr = HL_INVERSE;
2190     for (r = row; r < row + height; ++r)
2191     {
2192 	off = LineOffset[r];
2193 	max_off = off + screen_Columns;
2194 	for (c = col; c < col + width; ++c)
2195 	{
2196 	    if (enc_dbcs != 0 && dbcs_off2cells(off + c, max_off) > 1)
2197 	    {
2198 		screen_char_2(off + c, r, c);
2199 		++c;
2200 	    }
2201 	    else
2202 	    {
2203 		screen_char(off + c, r, c);
2204 		if (utf_off2cells(off + c, max_off) > 1)
2205 		    ++c;
2206 	    }
2207 	}
2208     }
2209     screen_char_attr = 0;
2210 }
2211 
2212 /*
2213  * Redraw the characters for a vertically split window.
2214  */
2215     static void
2216 redraw_block(int row, int end, win_T *wp)
2217 {
2218     int		col;
2219     int		width;
2220 
2221 # ifdef FEAT_CLIPBOARD
2222     clip_may_clear_selection(row, end - 1);
2223 # endif
2224 
2225     if (wp == NULL)
2226     {
2227 	col = 0;
2228 	width = Columns;
2229     }
2230     else
2231     {
2232 	col = wp->w_wincol;
2233 	width = wp->w_width;
2234     }
2235     screen_draw_rectangle(row, col, end - row, width, FALSE);
2236 }
2237 
2238     void
2239 space_to_screenline(int off, int attr)
2240 {
2241     ScreenLines[off] = ' ';
2242     ScreenAttrs[off] = attr;
2243     if (enc_utf8)
2244 	ScreenLinesUC[off] = 0;
2245 }
2246 
2247 /*
2248  * Fill the screen from 'start_row' to 'end_row', from 'start_col' to 'end_col'
2249  * with character 'c1' in first column followed by 'c2' in the other columns.
2250  * Use attributes 'attr'.
2251  */
2252     void
2253 screen_fill(
2254 	int	start_row,
2255 	int	end_row,
2256 	int	start_col,
2257 	int	end_col,
2258 	int	c1,
2259 	int	c2,
2260 	int	attr)
2261 {
2262     int	    row;
2263     int	    col;
2264     int	    off;
2265     int	    end_off;
2266     int	    did_delete;
2267     int	    c;
2268     int	    norm_term;
2269 #if defined(FEAT_GUI) || defined(UNIX)
2270     int	    force_next = FALSE;
2271 #endif
2272 
2273     if (end_row > screen_Rows)		// safety check
2274 	end_row = screen_Rows;
2275     if (end_col > screen_Columns)	// safety check
2276 	end_col = screen_Columns;
2277     if (ScreenLines == NULL
2278 	    || start_row >= end_row
2279 	    || start_col >= end_col)	// nothing to do
2280 	return;
2281 
2282     // it's a "normal" terminal when not in a GUI or cterm
2283     norm_term = (
2284 #ifdef FEAT_GUI
2285 	    !gui.in_use &&
2286 #endif
2287 	    !IS_CTERM);
2288     for (row = start_row; row < end_row; ++row)
2289     {
2290 	if (has_mbyte
2291 #ifdef FEAT_GUI
2292 		&& !gui.in_use
2293 #endif
2294 	   )
2295 	{
2296 	    // When drawing over the right halve of a double-wide char clear
2297 	    // out the left halve.  When drawing over the left halve of a
2298 	    // double wide-char clear out the right halve.  Only needed in a
2299 	    // terminal.
2300 	    if (start_col > 0 && mb_fix_col(start_col, row) != start_col)
2301 		screen_puts_len((char_u *)" ", 1, row, start_col - 1, 0);
2302 	    if (end_col < screen_Columns && mb_fix_col(end_col, row) != end_col)
2303 		screen_puts_len((char_u *)" ", 1, row, end_col, 0);
2304 	}
2305 	/*
2306 	 * Try to use delete-line termcap code, when no attributes or in a
2307 	 * "normal" terminal, where a bold/italic space is just a
2308 	 * space.
2309 	 */
2310 	did_delete = FALSE;
2311 	if (c2 == ' '
2312 		&& end_col == Columns
2313 		&& can_clear(T_CE)
2314 		&& (attr == 0
2315 		    || (norm_term
2316 			&& attr <= HL_ALL
2317 			&& ((attr & ~(HL_BOLD | HL_ITALIC)) == 0))))
2318 	{
2319 	    /*
2320 	     * check if we really need to clear something
2321 	     */
2322 	    col = start_col;
2323 	    if (c1 != ' ')			// don't clear first char
2324 		++col;
2325 
2326 	    off = LineOffset[row] + col;
2327 	    end_off = LineOffset[row] + end_col;
2328 
2329 	    // skip blanks (used often, keep it fast!)
2330 	    if (enc_utf8)
2331 		while (off < end_off && ScreenLines[off] == ' '
2332 			  && ScreenAttrs[off] == 0 && ScreenLinesUC[off] == 0)
2333 		    ++off;
2334 	    else
2335 		while (off < end_off && ScreenLines[off] == ' '
2336 						     && ScreenAttrs[off] == 0)
2337 		    ++off;
2338 	    if (off < end_off)		// something to be cleared
2339 	    {
2340 		col = off - LineOffset[row];
2341 		screen_stop_highlight();
2342 		term_windgoto(row, col);// clear rest of this screen line
2343 		out_str(T_CE);
2344 		screen_start();		// don't know where cursor is now
2345 		col = end_col - col;
2346 		while (col--)		// clear chars in ScreenLines
2347 		{
2348 		    space_to_screenline(off, 0);
2349 		    ++off;
2350 		}
2351 	    }
2352 	    did_delete = TRUE;		// the chars are cleared now
2353 	}
2354 
2355 	off = LineOffset[row] + start_col;
2356 	c = c1;
2357 	for (col = start_col; col < end_col; ++col)
2358 	{
2359 	    if ((ScreenLines[off] != c
2360 		    || (enc_utf8 && (int)ScreenLinesUC[off]
2361 						       != (c >= 0x80 ? c : 0))
2362 		    || ScreenAttrs[off] != attr
2363 #if defined(FEAT_GUI) || defined(UNIX)
2364 		    || force_next
2365 #endif
2366 		    )
2367 #ifdef FEAT_PROP_POPUP
2368 		    // Skip if under a(nother) popup.
2369 		    && !blocked_by_popup(row, col)
2370 #endif
2371 	       )
2372 	    {
2373 #if defined(FEAT_GUI) || defined(UNIX)
2374 		// The bold trick may make a single row of pixels appear in
2375 		// the next character.  When a bold character is removed, the
2376 		// next character should be redrawn too.  This happens for our
2377 		// own GUI and for some xterms.
2378 		if (
2379 # ifdef FEAT_GUI
2380 			gui.in_use
2381 # endif
2382 # if defined(FEAT_GUI) && defined(UNIX)
2383 			||
2384 # endif
2385 # ifdef UNIX
2386 			term_is_xterm
2387 # endif
2388 		   )
2389 		{
2390 		    if (ScreenLines[off] != ' '
2391 			    && (ScreenAttrs[off] > HL_ALL
2392 				|| ScreenAttrs[off] & HL_BOLD))
2393 			force_next = TRUE;
2394 		    else
2395 			force_next = FALSE;
2396 		}
2397 #endif
2398 		ScreenLines[off] = c;
2399 		if (enc_utf8)
2400 		{
2401 		    if (c >= 0x80)
2402 		    {
2403 			ScreenLinesUC[off] = c;
2404 			ScreenLinesC[0][off] = 0;
2405 		    }
2406 		    else
2407 			ScreenLinesUC[off] = 0;
2408 		}
2409 		ScreenAttrs[off] = attr;
2410 		if (!did_delete || c != ' ')
2411 		    screen_char(off, row, col);
2412 	    }
2413 	    ++off;
2414 	    if (col == start_col)
2415 	    {
2416 		if (did_delete)
2417 		    break;
2418 		c = c2;
2419 	    }
2420 	}
2421 	if (end_col == Columns)
2422 	    LineWraps[row] = FALSE;
2423 	if (row == Rows - 1)		// overwritten the command line
2424 	{
2425 	    redraw_cmdline = TRUE;
2426 	    if (start_col == 0 && end_col == Columns
2427 		    && c1 == ' ' && c2 == ' ' && attr == 0)
2428 		clear_cmdline = FALSE;	// command line has been cleared
2429 	    if (start_col == 0)
2430 		mode_displayed = FALSE; // mode cleared or overwritten
2431 	}
2432     }
2433 }
2434 
2435 /*
2436  * Check if there should be a delay.  Used before clearing or redrawing the
2437  * screen or the command line.
2438  */
2439     void
2440 check_for_delay(int check_msg_scroll)
2441 {
2442     if ((emsg_on_display || (check_msg_scroll && msg_scroll))
2443 	    && !did_wait_return
2444 	    && emsg_silent == 0)
2445     {
2446 	out_flush();
2447 	ui_delay(1006L, TRUE);
2448 	emsg_on_display = FALSE;
2449 	if (check_msg_scroll)
2450 	    msg_scroll = FALSE;
2451     }
2452 }
2453 
2454 /*
2455  * Init TabPageIdxs[] to zero: Clicking outside of tabs has no effect.
2456  */
2457     static void
2458 clear_TabPageIdxs(void)
2459 {
2460     int		scol;
2461 
2462     for (scol = 0; scol < Columns; ++scol)
2463 	TabPageIdxs[scol] = 0;
2464 }
2465 
2466 /*
2467  * screen_valid -  allocate screen buffers if size changed
2468  *   If "doclear" is TRUE: clear screen if it has been resized.
2469  *	Returns TRUE if there is a valid screen to write to.
2470  *	Returns FALSE when starting up and screen not initialized yet.
2471  */
2472     int
2473 screen_valid(int doclear)
2474 {
2475     screenalloc(doclear);	   // allocate screen buffers if size changed
2476     return (ScreenLines != NULL);
2477 }
2478 
2479 /*
2480  * Resize the shell to Rows and Columns.
2481  * Allocate ScreenLines[] and associated items.
2482  *
2483  * There may be some time between setting Rows and Columns and (re)allocating
2484  * ScreenLines[].  This happens when starting up and when (manually) changing
2485  * the shell size.  Always use screen_Rows and screen_Columns to access items
2486  * in ScreenLines[].  Use Rows and Columns for positioning text etc. where the
2487  * final size of the shell is needed.
2488  */
2489     void
2490 screenalloc(int doclear)
2491 {
2492     int		    new_row, old_row;
2493 #ifdef FEAT_GUI
2494     int		    old_Rows;
2495 #endif
2496     win_T	    *wp;
2497     int		    outofmem = FALSE;
2498     int		    len;
2499     schar_T	    *new_ScreenLines;
2500     u8char_T	    *new_ScreenLinesUC = NULL;
2501     u8char_T	    *new_ScreenLinesC[MAX_MCO];
2502     schar_T	    *new_ScreenLines2 = NULL;
2503     int		    i;
2504     sattr_T	    *new_ScreenAttrs;
2505     unsigned	    *new_LineOffset;
2506     char_u	    *new_LineWraps;
2507     short	    *new_TabPageIdxs;
2508 #ifdef FEAT_PROP_POPUP
2509     short	    *new_popup_mask;
2510     short	    *new_popup_mask_next;
2511     char	    *new_popup_transparent;
2512 #endif
2513     tabpage_T	    *tp;
2514     static int	    entered = FALSE;		// avoid recursiveness
2515     static int	    done_outofmem_msg = FALSE;	// did outofmem message
2516     int		    retry_count = 0;
2517 
2518 retry:
2519     /*
2520      * Allocation of the screen buffers is done only when the size changes and
2521      * when Rows and Columns have been set and we have started doing full
2522      * screen stuff.
2523      */
2524     if ((ScreenLines != NULL
2525 		&& Rows == screen_Rows
2526 		&& Columns == screen_Columns
2527 		&& enc_utf8 == (ScreenLinesUC != NULL)
2528 		&& (enc_dbcs == DBCS_JPNU) == (ScreenLines2 != NULL)
2529 		&& p_mco == Screen_mco)
2530 	    || Rows == 0
2531 	    || Columns == 0
2532 	    || (!full_screen && ScreenLines == NULL))
2533 	return;
2534 
2535     /*
2536      * It's possible that we produce an out-of-memory message below, which
2537      * will cause this function to be called again.  To break the loop, just
2538      * return here.
2539      */
2540     if (entered)
2541 	return;
2542     entered = TRUE;
2543 
2544     /*
2545      * Note that the window sizes are updated before reallocating the arrays,
2546      * thus we must not redraw here!
2547      */
2548     ++RedrawingDisabled;
2549 
2550     win_new_shellsize();    // fit the windows in the new sized shell
2551 
2552 #ifdef FEAT_GUI_HAIKU
2553     vim_lock_screen();  // be safe, put it here
2554 #endif
2555 
2556     comp_col();		// recompute columns for shown command and ruler
2557 
2558     /*
2559      * We're changing the size of the screen.
2560      * - Allocate new arrays for ScreenLines and ScreenAttrs.
2561      * - Move lines from the old arrays into the new arrays, clear extra
2562      *	 lines (unless the screen is going to be cleared).
2563      * - Free the old arrays.
2564      *
2565      * If anything fails, make ScreenLines NULL, so we don't do anything!
2566      * Continuing with the old ScreenLines may result in a crash, because the
2567      * size is wrong.
2568      */
2569     FOR_ALL_TAB_WINDOWS(tp, wp)
2570 	win_free_lsize(wp);
2571     if (aucmd_win != NULL)
2572 	win_free_lsize(aucmd_win);
2573 #ifdef FEAT_PROP_POPUP
2574     // global popup windows
2575     FOR_ALL_POPUPWINS(wp)
2576 	win_free_lsize(wp);
2577     // tab-local popup windows
2578     FOR_ALL_TABPAGES(tp)
2579 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
2580 	    win_free_lsize(wp);
2581 #endif
2582 
2583     new_ScreenLines = LALLOC_MULT(schar_T, (Rows + 1) * Columns);
2584     vim_memset(new_ScreenLinesC, 0, sizeof(u8char_T *) * MAX_MCO);
2585     if (enc_utf8)
2586     {
2587 	new_ScreenLinesUC = LALLOC_MULT(u8char_T, (Rows + 1) * Columns);
2588 	for (i = 0; i < p_mco; ++i)
2589 	    new_ScreenLinesC[i] = LALLOC_CLEAR_MULT(u8char_T,
2590 							 (Rows + 1) * Columns);
2591     }
2592     if (enc_dbcs == DBCS_JPNU)
2593 	new_ScreenLines2 = LALLOC_MULT(schar_T, (Rows + 1) * Columns);
2594     new_ScreenAttrs = LALLOC_MULT(sattr_T, (Rows + 1) * Columns);
2595     new_LineOffset = LALLOC_MULT(unsigned, Rows);
2596     new_LineWraps = LALLOC_MULT(char_u, Rows);
2597     new_TabPageIdxs = LALLOC_MULT(short, Columns);
2598 #ifdef FEAT_PROP_POPUP
2599     new_popup_mask = LALLOC_MULT(short, Rows * Columns);
2600     new_popup_mask_next = LALLOC_MULT(short, Rows * Columns);
2601     new_popup_transparent = LALLOC_MULT(char, Rows * Columns);
2602 #endif
2603 
2604     FOR_ALL_TAB_WINDOWS(tp, wp)
2605     {
2606 	if (win_alloc_lines(wp) == FAIL)
2607 	{
2608 	    outofmem = TRUE;
2609 	    goto give_up;
2610 	}
2611     }
2612     if (aucmd_win != NULL && aucmd_win->w_lines == NULL
2613 					&& win_alloc_lines(aucmd_win) == FAIL)
2614 	outofmem = TRUE;
2615 #ifdef FEAT_PROP_POPUP
2616     // global popup windows
2617     FOR_ALL_POPUPWINS(wp)
2618 	if (win_alloc_lines(wp) == FAIL)
2619 	{
2620 	    outofmem = TRUE;
2621 	    goto give_up;
2622 	}
2623     // tab-local popup windows
2624     FOR_ALL_TABPAGES(tp)
2625 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
2626 	    if (win_alloc_lines(wp) == FAIL)
2627 	    {
2628 		outofmem = TRUE;
2629 		goto give_up;
2630 	    }
2631 #endif
2632 
2633 give_up:
2634 
2635     for (i = 0; i < p_mco; ++i)
2636 	if (new_ScreenLinesC[i] == NULL)
2637 	    break;
2638     if (new_ScreenLines == NULL
2639 	    || (enc_utf8 && (new_ScreenLinesUC == NULL || i != p_mco))
2640 	    || (enc_dbcs == DBCS_JPNU && new_ScreenLines2 == NULL)
2641 	    || new_ScreenAttrs == NULL
2642 	    || new_LineOffset == NULL
2643 	    || new_LineWraps == NULL
2644 	    || new_TabPageIdxs == NULL
2645 #ifdef FEAT_PROP_POPUP
2646 	    || new_popup_mask == NULL
2647 	    || new_popup_mask_next == NULL
2648 	    || new_popup_transparent == NULL
2649 #endif
2650 	    || outofmem)
2651     {
2652 	if (ScreenLines != NULL || !done_outofmem_msg)
2653 	{
2654 	    // guess the size
2655 	    do_outofmem_msg((long_u)((Rows + 1) * Columns));
2656 
2657 	    // Remember we did this to avoid getting outofmem messages over
2658 	    // and over again.
2659 	    done_outofmem_msg = TRUE;
2660 	}
2661 	VIM_CLEAR(new_ScreenLines);
2662 	VIM_CLEAR(new_ScreenLinesUC);
2663 	for (i = 0; i < p_mco; ++i)
2664 	    VIM_CLEAR(new_ScreenLinesC[i]);
2665 	VIM_CLEAR(new_ScreenLines2);
2666 	VIM_CLEAR(new_ScreenAttrs);
2667 	VIM_CLEAR(new_LineOffset);
2668 	VIM_CLEAR(new_LineWraps);
2669 	VIM_CLEAR(new_TabPageIdxs);
2670 #ifdef FEAT_PROP_POPUP
2671 	VIM_CLEAR(new_popup_mask);
2672 	VIM_CLEAR(new_popup_mask_next);
2673 	VIM_CLEAR(new_popup_transparent);
2674 #endif
2675     }
2676     else
2677     {
2678 	done_outofmem_msg = FALSE;
2679 
2680 	for (new_row = 0; new_row < Rows; ++new_row)
2681 	{
2682 	    new_LineOffset[new_row] = new_row * Columns;
2683 	    new_LineWraps[new_row] = FALSE;
2684 
2685 	    /*
2686 	     * If the screen is not going to be cleared, copy as much as
2687 	     * possible from the old screen to the new one and clear the rest
2688 	     * (used when resizing the window at the "--more--" prompt or when
2689 	     * executing an external command, for the GUI).
2690 	     */
2691 	    if (!doclear)
2692 	    {
2693 		(void)vim_memset(new_ScreenLines + new_row * Columns,
2694 				      ' ', (size_t)Columns * sizeof(schar_T));
2695 		if (enc_utf8)
2696 		{
2697 		    (void)vim_memset(new_ScreenLinesUC + new_row * Columns,
2698 				       0, (size_t)Columns * sizeof(u8char_T));
2699 		    for (i = 0; i < p_mco; ++i)
2700 			(void)vim_memset(new_ScreenLinesC[i]
2701 							  + new_row * Columns,
2702 				       0, (size_t)Columns * sizeof(u8char_T));
2703 		}
2704 		if (enc_dbcs == DBCS_JPNU)
2705 		    (void)vim_memset(new_ScreenLines2 + new_row * Columns,
2706 				       0, (size_t)Columns * sizeof(schar_T));
2707 		(void)vim_memset(new_ScreenAttrs + new_row * Columns,
2708 					0, (size_t)Columns * sizeof(sattr_T));
2709 		old_row = new_row + (screen_Rows - Rows);
2710 		if (old_row >= 0 && ScreenLines != NULL)
2711 		{
2712 		    if (screen_Columns < Columns)
2713 			len = screen_Columns;
2714 		    else
2715 			len = Columns;
2716 		    // When switching to utf-8 don't copy characters, they
2717 		    // may be invalid now.  Also when p_mco changes.
2718 		    if (!(enc_utf8 && ScreenLinesUC == NULL)
2719 						       && p_mco == Screen_mco)
2720 			mch_memmove(new_ScreenLines + new_LineOffset[new_row],
2721 				ScreenLines + LineOffset[old_row],
2722 				(size_t)len * sizeof(schar_T));
2723 		    if (enc_utf8 && ScreenLinesUC != NULL
2724 						       && p_mco == Screen_mco)
2725 		    {
2726 			mch_memmove(new_ScreenLinesUC + new_LineOffset[new_row],
2727 				ScreenLinesUC + LineOffset[old_row],
2728 				(size_t)len * sizeof(u8char_T));
2729 			for (i = 0; i < p_mco; ++i)
2730 			    mch_memmove(new_ScreenLinesC[i]
2731 						    + new_LineOffset[new_row],
2732 				ScreenLinesC[i] + LineOffset[old_row],
2733 				(size_t)len * sizeof(u8char_T));
2734 		    }
2735 		    if (enc_dbcs == DBCS_JPNU && ScreenLines2 != NULL)
2736 			mch_memmove(new_ScreenLines2 + new_LineOffset[new_row],
2737 				ScreenLines2 + LineOffset[old_row],
2738 				(size_t)len * sizeof(schar_T));
2739 		    mch_memmove(new_ScreenAttrs + new_LineOffset[new_row],
2740 			    ScreenAttrs + LineOffset[old_row],
2741 			    (size_t)len * sizeof(sattr_T));
2742 		}
2743 	    }
2744 	}
2745 	// Use the last line of the screen for the current line.
2746 	current_ScreenLine = new_ScreenLines + Rows * Columns;
2747 
2748 #ifdef FEAT_PROP_POPUP
2749 	vim_memset(new_popup_mask, 0, Rows * Columns * sizeof(short));
2750 	vim_memset(new_popup_transparent, 0, Rows * Columns * sizeof(char));
2751 #endif
2752     }
2753 
2754     free_screenlines();
2755 
2756     // NOTE: this may result in all pointers to become NULL.
2757     ScreenLines = new_ScreenLines;
2758     ScreenLinesUC = new_ScreenLinesUC;
2759     for (i = 0; i < p_mco; ++i)
2760 	ScreenLinesC[i] = new_ScreenLinesC[i];
2761     Screen_mco = p_mco;
2762     ScreenLines2 = new_ScreenLines2;
2763     ScreenAttrs = new_ScreenAttrs;
2764     LineOffset = new_LineOffset;
2765     LineWraps = new_LineWraps;
2766     TabPageIdxs = new_TabPageIdxs;
2767 #ifdef FEAT_PROP_POPUP
2768     popup_mask = new_popup_mask;
2769     popup_mask_next = new_popup_mask_next;
2770     popup_transparent = new_popup_transparent;
2771     popup_mask_refresh = TRUE;
2772 #endif
2773 
2774     // It's important that screen_Rows and screen_Columns reflect the actual
2775     // size of ScreenLines[].  Set them before calling anything.
2776 #ifdef FEAT_GUI
2777     old_Rows = screen_Rows;
2778 #endif
2779     screen_Rows = Rows;
2780     screen_Columns = Columns;
2781 
2782     must_redraw = CLEAR;	// need to clear the screen later
2783     if (doclear)
2784 	screenclear2();
2785 #ifdef FEAT_GUI
2786     else if (gui.in_use
2787 	    && !gui.starting
2788 	    && ScreenLines != NULL
2789 	    && old_Rows != Rows)
2790     {
2791 	gui_redraw_block(0, 0, (int)Rows - 1, (int)Columns - 1, 0);
2792 
2793 	// Adjust the position of the cursor, for when executing an external
2794 	// command.
2795 	if (msg_row >= Rows)		// Rows got smaller
2796 	    msg_row = Rows - 1;		// put cursor at last row
2797 	else if (Rows > old_Rows)	// Rows got bigger
2798 	    msg_row += Rows - old_Rows; // put cursor in same place
2799 	if (msg_col >= Columns)		// Columns got smaller
2800 	    msg_col = Columns - 1;	// put cursor at last column
2801     }
2802 #endif
2803     clear_TabPageIdxs();
2804 
2805 #ifdef FEAT_GUI_HAIKU
2806     vim_unlock_screen();
2807 #endif
2808 
2809     entered = FALSE;
2810     --RedrawingDisabled;
2811 
2812     /*
2813      * Do not apply autocommands more than 3 times to avoid an endless loop
2814      * in case applying autocommands always changes Rows or Columns.
2815      */
2816     if (starting == 0 && ++retry_count <= 3)
2817     {
2818 	apply_autocmds(EVENT_VIMRESIZED, NULL, NULL, FALSE, curbuf);
2819 	// In rare cases, autocommands may have altered Rows or Columns,
2820 	// jump back to check if we need to allocate the screen again.
2821 	goto retry;
2822     }
2823 }
2824 
2825     void
2826 free_screenlines(void)
2827 {
2828     int		i;
2829 
2830     VIM_CLEAR(ScreenLinesUC);
2831     for (i = 0; i < Screen_mco; ++i)
2832 	VIM_CLEAR(ScreenLinesC[i]);
2833     VIM_CLEAR(ScreenLines2);
2834     VIM_CLEAR(ScreenLines);
2835     VIM_CLEAR(ScreenAttrs);
2836     VIM_CLEAR(LineOffset);
2837     VIM_CLEAR(LineWraps);
2838     VIM_CLEAR(TabPageIdxs);
2839 #ifdef FEAT_PROP_POPUP
2840     VIM_CLEAR(popup_mask);
2841     VIM_CLEAR(popup_mask_next);
2842     VIM_CLEAR(popup_transparent);
2843 #endif
2844 }
2845 
2846     void
2847 screenclear(void)
2848 {
2849     check_for_delay(FALSE);
2850     screenalloc(FALSE);	    // allocate screen buffers if size changed
2851     screenclear2();	    // clear the screen
2852 }
2853 
2854     static void
2855 screenclear2(void)
2856 {
2857     int	    i;
2858 
2859     if (starting == NO_SCREEN || ScreenLines == NULL
2860 #ifdef FEAT_GUI
2861 	    || (gui.in_use && gui.starting)
2862 #endif
2863 	    )
2864 	return;
2865 
2866 #ifdef FEAT_GUI
2867     if (!gui.in_use)
2868 #endif
2869 	screen_attr = -1;	// force setting the Normal colors
2870     screen_stop_highlight();	// don't want highlighting here
2871 
2872 #ifdef FEAT_CLIPBOARD
2873     // disable selection without redrawing it
2874     clip_scroll_selection(9999);
2875 #endif
2876 
2877     // blank out ScreenLines
2878     for (i = 0; i < Rows; ++i)
2879     {
2880 	lineclear(LineOffset[i], (int)Columns, 0);
2881 	LineWraps[i] = FALSE;
2882     }
2883 
2884     if (can_clear(T_CL))
2885     {
2886 	out_str(T_CL);		// clear the display
2887 	clear_cmdline = FALSE;
2888 	mode_displayed = FALSE;
2889     }
2890     else
2891     {
2892 	// can't clear the screen, mark all chars with invalid attributes
2893 	for (i = 0; i < Rows; ++i)
2894 	    lineinvalid(LineOffset[i], (int)Columns);
2895 	clear_cmdline = TRUE;
2896     }
2897 
2898     screen_cleared = TRUE;	// can use contents of ScreenLines now
2899 
2900     win_rest_invalid(firstwin);
2901     redraw_cmdline = TRUE;
2902     redraw_tabline = TRUE;
2903     if (must_redraw == CLEAR)	// no need to clear again
2904 	must_redraw = NOT_VALID;
2905     compute_cmdrow();
2906     msg_row = cmdline_row;	// put cursor on last line for messages
2907     msg_col = 0;
2908     screen_start();		// don't know where cursor is now
2909     msg_scrolled = 0;		// can't scroll back
2910     msg_didany = FALSE;
2911     msg_didout = FALSE;
2912 }
2913 
2914 /*
2915  * Clear one line in ScreenLines.
2916  */
2917     static void
2918 lineclear(unsigned off, int width, int attr)
2919 {
2920     (void)vim_memset(ScreenLines + off, ' ', (size_t)width * sizeof(schar_T));
2921     if (enc_utf8)
2922 	(void)vim_memset(ScreenLinesUC + off, 0,
2923 					  (size_t)width * sizeof(u8char_T));
2924     (void)vim_memset(ScreenAttrs + off, attr, (size_t)width * sizeof(sattr_T));
2925 }
2926 
2927 /*
2928  * Mark one line in ScreenLines invalid by setting the attributes to an
2929  * invalid value.
2930  */
2931     static void
2932 lineinvalid(unsigned off, int width)
2933 {
2934     (void)vim_memset(ScreenAttrs + off, -1, (size_t)width * sizeof(sattr_T));
2935 }
2936 
2937 /*
2938  * Copy part of a Screenline for vertically split window "wp".
2939  */
2940     static void
2941 linecopy(int to, int from, win_T *wp)
2942 {
2943     unsigned	off_to = LineOffset[to] + wp->w_wincol;
2944     unsigned	off_from = LineOffset[from] + wp->w_wincol;
2945 
2946     mch_memmove(ScreenLines + off_to, ScreenLines + off_from,
2947 	    wp->w_width * sizeof(schar_T));
2948     if (enc_utf8)
2949     {
2950 	int	i;
2951 
2952 	mch_memmove(ScreenLinesUC + off_to, ScreenLinesUC + off_from,
2953 		wp->w_width * sizeof(u8char_T));
2954 	for (i = 0; i < p_mco; ++i)
2955 	    mch_memmove(ScreenLinesC[i] + off_to, ScreenLinesC[i] + off_from,
2956 		    wp->w_width * sizeof(u8char_T));
2957     }
2958     if (enc_dbcs == DBCS_JPNU)
2959 	mch_memmove(ScreenLines2 + off_to, ScreenLines2 + off_from,
2960 		wp->w_width * sizeof(schar_T));
2961     mch_memmove(ScreenAttrs + off_to, ScreenAttrs + off_from,
2962 	    wp->w_width * sizeof(sattr_T));
2963 }
2964 
2965 /*
2966  * Return TRUE if clearing with term string "p" would work.
2967  * It can't work when the string is empty or it won't set the right background.
2968  * Don't clear to end-of-line when there are popups, it may cause flicker.
2969  */
2970     int
2971 can_clear(char_u *p)
2972 {
2973     return (*p != NUL && (t_colors <= 1
2974 #ifdef FEAT_GUI
2975 		|| gui.in_use
2976 #endif
2977 #ifdef FEAT_TERMGUICOLORS
2978 		|| (p_tgc && cterm_normal_bg_gui_color == INVALCOLOR)
2979 		|| (!p_tgc && cterm_normal_bg_color == 0)
2980 #else
2981 		|| cterm_normal_bg_color == 0
2982 #endif
2983 		|| *T_UT != NUL)
2984 #ifdef FEAT_PROP_POPUP
2985 	    && !(p == T_CE && popup_visible)
2986 #endif
2987 	    );
2988 }
2989 
2990 /*
2991  * Reset cursor position. Use whenever cursor was moved because of outputting
2992  * something directly to the screen (shell commands) or a terminal control
2993  * code.
2994  */
2995     void
2996 screen_start(void)
2997 {
2998     screen_cur_row = screen_cur_col = 9999;
2999 }
3000 
3001 /*
3002  * Move the cursor to position "row","col" in the screen.
3003  * This tries to find the most efficient way to move, minimizing the number of
3004  * characters sent to the terminal.
3005  */
3006     void
3007 windgoto(int row, int col)
3008 {
3009     sattr_T	    *p;
3010     int		    i;
3011     int		    plan;
3012     int		    cost;
3013     int		    wouldbe_col;
3014     int		    noinvcurs;
3015     char_u	    *bs;
3016     int		    goto_cost;
3017     int		    attr;
3018 
3019 #define GOTO_COST   7	// assume a term_windgoto() takes about 7 chars
3020 #define HIGHL_COST  5	// assume unhighlight takes 5 chars
3021 
3022 #define PLAN_LE	    1
3023 #define PLAN_CR	    2
3024 #define PLAN_NL	    3
3025 #define PLAN_WRITE  4
3026     // Can't use ScreenLines unless initialized
3027     if (ScreenLines == NULL)
3028 	return;
3029 
3030     if (col != screen_cur_col || row != screen_cur_row)
3031     {
3032 	// Check for valid position.
3033 	if (row < 0)	// window without text lines?
3034 	    row = 0;
3035 	if (row >= screen_Rows)
3036 	    row = screen_Rows - 1;
3037 	if (col >= screen_Columns)
3038 	    col = screen_Columns - 1;
3039 
3040 	// check if no cursor movement is allowed in highlight mode
3041 	if (screen_attr && *T_MS == NUL)
3042 	    noinvcurs = HIGHL_COST;
3043 	else
3044 	    noinvcurs = 0;
3045 	goto_cost = GOTO_COST + noinvcurs;
3046 
3047 	/*
3048 	 * Plan how to do the positioning:
3049 	 * 1. Use CR to move it to column 0, same row.
3050 	 * 2. Use T_LE to move it a few columns to the left.
3051 	 * 3. Use NL to move a few lines down, column 0.
3052 	 * 4. Move a few columns to the right with T_ND or by writing chars.
3053 	 *
3054 	 * Don't do this if the cursor went beyond the last column, the cursor
3055 	 * position is unknown then (some terminals wrap, some don't )
3056 	 *
3057 	 * First check if the highlighting attributes allow us to write
3058 	 * characters to move the cursor to the right.
3059 	 */
3060 	if (row >= screen_cur_row && screen_cur_col < Columns)
3061 	{
3062 	    /*
3063 	     * If the cursor is in the same row, bigger col, we can use CR
3064 	     * or T_LE.
3065 	     */
3066 	    bs = NULL;			    // init for GCC
3067 	    attr = screen_attr;
3068 	    if (row == screen_cur_row && col < screen_cur_col)
3069 	    {
3070 		// "le" is preferred over "bc", because "bc" is obsolete
3071 		if (*T_LE)
3072 		    bs = T_LE;		    // "cursor left"
3073 		else
3074 		    bs = T_BC;		    // "backspace character (old)
3075 		if (*bs)
3076 		    cost = (screen_cur_col - col) * (int)STRLEN(bs);
3077 		else
3078 		    cost = 999;
3079 		if (col + 1 < cost)	    // using CR is less characters
3080 		{
3081 		    plan = PLAN_CR;
3082 		    wouldbe_col = 0;
3083 		    cost = 1;		    // CR is just one character
3084 		}
3085 		else
3086 		{
3087 		    plan = PLAN_LE;
3088 		    wouldbe_col = col;
3089 		}
3090 		if (noinvcurs)		    // will stop highlighting
3091 		{
3092 		    cost += noinvcurs;
3093 		    attr = 0;
3094 		}
3095 	    }
3096 
3097 	    /*
3098 	     * If the cursor is above where we want to be, we can use CR LF.
3099 	     */
3100 	    else if (row > screen_cur_row)
3101 	    {
3102 		plan = PLAN_NL;
3103 		wouldbe_col = 0;
3104 		cost = (row - screen_cur_row) * 2;  // CR LF
3105 		if (noinvcurs)		    // will stop highlighting
3106 		{
3107 		    cost += noinvcurs;
3108 		    attr = 0;
3109 		}
3110 	    }
3111 
3112 	    /*
3113 	     * If the cursor is in the same row, smaller col, just use write.
3114 	     */
3115 	    else
3116 	    {
3117 		plan = PLAN_WRITE;
3118 		wouldbe_col = screen_cur_col;
3119 		cost = 0;
3120 	    }
3121 
3122 	    /*
3123 	     * Check if any characters that need to be written have the
3124 	     * correct attributes.  Also avoid UTF-8 characters.
3125 	     */
3126 	    i = col - wouldbe_col;
3127 	    if (i > 0)
3128 		cost += i;
3129 	    if (cost < goto_cost && i > 0)
3130 	    {
3131 		/*
3132 		 * Check if the attributes are correct without additionally
3133 		 * stopping highlighting.
3134 		 */
3135 		p = ScreenAttrs + LineOffset[row] + wouldbe_col;
3136 		while (i && *p++ == attr)
3137 		    --i;
3138 		if (i != 0)
3139 		{
3140 		    /*
3141 		     * Try if it works when highlighting is stopped here.
3142 		     */
3143 		    if (*--p == 0)
3144 		    {
3145 			cost += noinvcurs;
3146 			while (i && *p++ == 0)
3147 			    --i;
3148 		    }
3149 		    if (i != 0)
3150 			cost = 999;	// different attributes, don't do it
3151 		}
3152 		if (enc_utf8)
3153 		{
3154 		    // Don't use an UTF-8 char for positioning, it's slow.
3155 		    for (i = wouldbe_col; i < col; ++i)
3156 			if (ScreenLinesUC[LineOffset[row] + i] != 0)
3157 			{
3158 			    cost = 999;
3159 			    break;
3160 			}
3161 		}
3162 	    }
3163 
3164 	    /*
3165 	     * We can do it without term_windgoto()!
3166 	     */
3167 	    if (cost < goto_cost)
3168 	    {
3169 		if (plan == PLAN_LE)
3170 		{
3171 		    if (noinvcurs)
3172 			screen_stop_highlight();
3173 		    while (screen_cur_col > col)
3174 		    {
3175 			out_str(bs);
3176 			--screen_cur_col;
3177 		    }
3178 		}
3179 		else if (plan == PLAN_CR)
3180 		{
3181 		    if (noinvcurs)
3182 			screen_stop_highlight();
3183 		    out_char('\r');
3184 		    screen_cur_col = 0;
3185 		}
3186 		else if (plan == PLAN_NL)
3187 		{
3188 		    if (noinvcurs)
3189 			screen_stop_highlight();
3190 		    while (screen_cur_row < row)
3191 		    {
3192 			out_char('\n');
3193 			++screen_cur_row;
3194 		    }
3195 		    screen_cur_col = 0;
3196 		}
3197 
3198 		i = col - screen_cur_col;
3199 		if (i > 0)
3200 		{
3201 		    /*
3202 		     * Use cursor-right if it's one character only.  Avoids
3203 		     * removing a line of pixels from the last bold char, when
3204 		     * using the bold trick in the GUI.
3205 		     */
3206 		    if (T_ND[0] != NUL && T_ND[1] == NUL)
3207 		    {
3208 			while (i-- > 0)
3209 			    out_char(*T_ND);
3210 		    }
3211 		    else
3212 		    {
3213 			int	off;
3214 
3215 			off = LineOffset[row] + screen_cur_col;
3216 			while (i-- > 0)
3217 			{
3218 			    if (ScreenAttrs[off] != screen_attr)
3219 				screen_stop_highlight();
3220 			    out_flush_check();
3221 			    out_char(ScreenLines[off]);
3222 			    if (enc_dbcs == DBCS_JPNU
3223 						  && ScreenLines[off] == 0x8e)
3224 				out_char(ScreenLines2[off]);
3225 			    ++off;
3226 			}
3227 		    }
3228 		}
3229 	    }
3230 	}
3231 	else
3232 	    cost = 999;
3233 
3234 	if (cost >= goto_cost)
3235 	{
3236 	    if (noinvcurs)
3237 		screen_stop_highlight();
3238 	    if (row == screen_cur_row && (col > screen_cur_col)
3239 							     && *T_CRI != NUL)
3240 		term_cursor_right(col - screen_cur_col);
3241 	    else
3242 		term_windgoto(row, col);
3243 	}
3244 	screen_cur_row = row;
3245 	screen_cur_col = col;
3246     }
3247 }
3248 
3249 /*
3250  * Set cursor to its position in the current window.
3251  */
3252     void
3253 setcursor(void)
3254 {
3255     setcursor_mayforce(FALSE);
3256 }
3257 
3258 /*
3259  * Set cursor to its position in the current window.
3260  * When "force" is TRUE also when not redrawing.
3261  */
3262     void
3263 setcursor_mayforce(int force)
3264 {
3265     if (force || redrawing())
3266     {
3267 	validate_cursor();
3268 	windgoto(W_WINROW(curwin) + curwin->w_wrow,
3269 		curwin->w_wincol + (
3270 #ifdef FEAT_RIGHTLEFT
3271 		// With 'rightleft' set and the cursor on a double-wide
3272 		// character, position it on the leftmost column.
3273 		curwin->w_p_rl ? ((int)curwin->w_width - curwin->w_wcol
3274 		    - ((has_mbyte
3275 			   && (*mb_ptr2cells)(ml_get_cursor()) == 2
3276 			   && vim_isprintc(gchar_cursor())) ? 2 : 1)) :
3277 #endif
3278 							    curwin->w_wcol));
3279     }
3280 }
3281 
3282 
3283 /*
3284  * Insert 'line_count' lines at 'row' in window 'wp'.
3285  * If 'invalid' is TRUE the wp->w_lines[].wl_lnum is invalidated.
3286  * If 'mayclear' is TRUE the screen will be cleared if it is faster than
3287  * scrolling.
3288  * Returns FAIL if the lines are not inserted, OK for success.
3289  */
3290     int
3291 win_ins_lines(
3292     win_T	*wp,
3293     int		row,
3294     int		line_count,
3295     int		invalid,
3296     int		mayclear)
3297 {
3298     int		did_delete;
3299     int		nextrow;
3300     int		lastrow;
3301     int		retval;
3302 
3303     if (invalid)
3304 	wp->w_lines_valid = 0;
3305 
3306     if (wp->w_height < 5)
3307 	return FAIL;
3308 
3309     if (line_count > wp->w_height - row)
3310 	line_count = wp->w_height - row;
3311 
3312     retval = win_do_lines(wp, row, line_count, mayclear, FALSE, 0);
3313     if (retval != MAYBE)
3314 	return retval;
3315 
3316     /*
3317      * If there is a next window or a status line, we first try to delete the
3318      * lines at the bottom to avoid messing what is after the window.
3319      * If this fails and there are following windows, don't do anything to
3320      * avoid messing up those windows, better just redraw.
3321      */
3322     did_delete = FALSE;
3323     if (wp->w_next != NULL || wp->w_status_height)
3324     {
3325 	if (screen_del_lines(0, W_WINROW(wp) + wp->w_height - line_count,
3326 				  line_count, (int)Rows, FALSE, 0, NULL) == OK)
3327 	    did_delete = TRUE;
3328 	else if (wp->w_next)
3329 	    return FAIL;
3330     }
3331     /*
3332      * if no lines deleted, blank the lines that will end up below the window
3333      */
3334     if (!did_delete)
3335     {
3336 	wp->w_redr_status = TRUE;
3337 	redraw_cmdline = TRUE;
3338 	nextrow = W_WINROW(wp) + wp->w_height + wp->w_status_height;
3339 	lastrow = nextrow + line_count;
3340 	if (lastrow > Rows)
3341 	    lastrow = Rows;
3342 	screen_fill(nextrow - line_count, lastrow - line_count,
3343 		  wp->w_wincol, (int)W_ENDCOL(wp),
3344 		  ' ', ' ', 0);
3345     }
3346 
3347     if (screen_ins_lines(0, W_WINROW(wp) + row, line_count, (int)Rows, 0, NULL)
3348 								      == FAIL)
3349     {
3350 	// deletion will have messed up other windows
3351 	if (did_delete)
3352 	{
3353 	    wp->w_redr_status = TRUE;
3354 	    win_rest_invalid(W_NEXT(wp));
3355 	}
3356 	return FAIL;
3357     }
3358 
3359     return OK;
3360 }
3361 
3362 /*
3363  * Delete "line_count" window lines at "row" in window "wp".
3364  * If "invalid" is TRUE curwin->w_lines[] is invalidated.
3365  * If "mayclear" is TRUE the screen will be cleared if it is faster than
3366  * scrolling
3367  * Return OK for success, FAIL if the lines are not deleted.
3368  */
3369     int
3370 win_del_lines(
3371     win_T	*wp,
3372     int		row,
3373     int		line_count,
3374     int		invalid,
3375     int		mayclear,
3376     int		clear_attr)	    // for clearing lines
3377 {
3378     int		retval;
3379 
3380     if (invalid)
3381 	wp->w_lines_valid = 0;
3382 
3383     if (line_count > wp->w_height - row)
3384 	line_count = wp->w_height - row;
3385 
3386     retval = win_do_lines(wp, row, line_count, mayclear, TRUE, clear_attr);
3387     if (retval != MAYBE)
3388 	return retval;
3389 
3390     if (screen_del_lines(0, W_WINROW(wp) + row, line_count,
3391 				   (int)Rows, FALSE, clear_attr, NULL) == FAIL)
3392 	return FAIL;
3393 
3394     /*
3395      * If there are windows or status lines below, try to put them at the
3396      * correct place. If we can't do that, they have to be redrawn.
3397      */
3398     if (wp->w_next || wp->w_status_height || cmdline_row < Rows - 1)
3399     {
3400 	if (screen_ins_lines(0, W_WINROW(wp) + wp->w_height - line_count,
3401 			      line_count, (int)Rows, clear_attr, NULL) == FAIL)
3402 	{
3403 	    wp->w_redr_status = TRUE;
3404 	    win_rest_invalid(wp->w_next);
3405 	}
3406     }
3407     /*
3408      * If this is the last window and there is no status line, redraw the
3409      * command line later.
3410      */
3411     else
3412 	redraw_cmdline = TRUE;
3413     return OK;
3414 }
3415 
3416 /*
3417  * Common code for win_ins_lines() and win_del_lines().
3418  * Returns OK or FAIL when the work has been done.
3419  * Returns MAYBE when not finished yet.
3420  */
3421     static int
3422 win_do_lines(
3423     win_T	*wp,
3424     int		row,
3425     int		line_count,
3426     int		mayclear,
3427     int		del,
3428     int		clear_attr)
3429 {
3430     int		retval;
3431 
3432     if (!redrawing() || line_count <= 0)
3433 	return FAIL;
3434 
3435     // When inserting lines would result in loss of command output, just redraw
3436     // the lines.
3437     if (no_win_do_lines_ins && !del)
3438 	return FAIL;
3439 
3440     // only a few lines left: redraw is faster
3441     if (mayclear && Rows - line_count < 5 && wp->w_width == Columns)
3442     {
3443 	if (!no_win_do_lines_ins)
3444 	    screenclear();	    // will set wp->w_lines_valid to 0
3445 	return FAIL;
3446     }
3447 
3448 #ifdef FEAT_PROP_POPUP
3449     // this doesn't work when there are popups visible
3450     if (popup_visible)
3451 	return FAIL;
3452 #endif
3453 
3454     // Delete all remaining lines
3455     if (row + line_count >= wp->w_height)
3456     {
3457 	screen_fill(W_WINROW(wp) + row, W_WINROW(wp) + wp->w_height,
3458 		wp->w_wincol, (int)W_ENDCOL(wp),
3459 		' ', ' ', 0);
3460 	return OK;
3461     }
3462 
3463     /*
3464      * When scrolling, the message on the command line should be cleared,
3465      * otherwise it will stay there forever.
3466      * Don't do this when avoiding to insert lines.
3467      */
3468     if (!no_win_do_lines_ins)
3469 	clear_cmdline = TRUE;
3470 
3471     /*
3472      * If the terminal can set a scroll region, use that.
3473      * Always do this in a vertically split window.  This will redraw from
3474      * ScreenLines[] when t_CV isn't defined.  That's faster than using
3475      * win_line().
3476      * Don't use a scroll region when we are going to redraw the text, writing
3477      * a character in the lower right corner of the scroll region may cause a
3478      * scroll-up .
3479      */
3480     if (scroll_region || wp->w_width != Columns)
3481     {
3482 	if (scroll_region && (wp->w_width == Columns || *T_CSV != NUL))
3483 	    scroll_region_set(wp, row);
3484 	if (del)
3485 	    retval = screen_del_lines(W_WINROW(wp) + row, 0, line_count,
3486 				    wp->w_height - row, FALSE, clear_attr, wp);
3487 	else
3488 	    retval = screen_ins_lines(W_WINROW(wp) + row, 0, line_count,
3489 					   wp->w_height - row, clear_attr, wp);
3490 	if (scroll_region && (wp->w_width == Columns || *T_CSV != NUL))
3491 	    scroll_region_reset();
3492 	return retval;
3493     }
3494 
3495     if (wp->w_next != NULL && p_tf) // don't delete/insert on fast terminal
3496 	return FAIL;
3497 
3498     return MAYBE;
3499 }
3500 
3501 /*
3502  * window 'wp' and everything after it is messed up, mark it for redraw
3503  */
3504     static void
3505 win_rest_invalid(win_T *wp)
3506 {
3507     while (wp != NULL)
3508     {
3509 	redraw_win_later(wp, NOT_VALID);
3510 	wp->w_redr_status = TRUE;
3511 	wp = wp->w_next;
3512     }
3513     redraw_cmdline = TRUE;
3514 }
3515 
3516 /*
3517  * The rest of the routines in this file perform screen manipulations. The
3518  * given operation is performed physically on the screen. The corresponding
3519  * change is also made to the internal screen image. In this way, the editor
3520  * anticipates the effect of editing changes on the appearance of the screen.
3521  * That way, when we call screenupdate a complete redraw isn't usually
3522  * necessary. Another advantage is that we can keep adding code to anticipate
3523  * screen changes, and in the meantime, everything still works.
3524  */
3525 
3526 /*
3527  * types for inserting or deleting lines
3528  */
3529 #define USE_T_CAL   1
3530 #define USE_T_CDL   2
3531 #define USE_T_AL    3
3532 #define USE_T_CE    4
3533 #define USE_T_DL    5
3534 #define USE_T_SR    6
3535 #define USE_NL	    7
3536 #define USE_T_CD    8
3537 #define USE_REDRAW  9
3538 
3539 /*
3540  * insert lines on the screen and update ScreenLines[]
3541  * 'end' is the line after the scrolled part. Normally it is Rows.
3542  * When scrolling region used 'off' is the offset from the top for the region.
3543  * 'row' and 'end' are relative to the start of the region.
3544  *
3545  * return FAIL for failure, OK for success.
3546  */
3547     int
3548 screen_ins_lines(
3549     int		off,
3550     int		row,
3551     int		line_count,
3552     int		end,
3553     int		clear_attr,
3554     win_T	*wp)	    // NULL or window to use width from
3555 {
3556     int		i;
3557     int		j;
3558     unsigned	temp;
3559     int		cursor_row;
3560     int		cursor_col = 0;
3561     int		type;
3562     int		result_empty;
3563     int		can_ce = can_clear(T_CE);
3564 
3565     /*
3566      * FAIL if
3567      * - there is no valid screen
3568      * - the screen has to be redrawn completely
3569      * - the line count is less than one
3570      * - the line count is more than 'ttyscroll'
3571      * - redrawing for a callback and there is a modeless selection
3572      * - there is a popup window
3573      */
3574      if (!screen_valid(TRUE)
3575 	     || line_count <= 0 || line_count > p_ttyscroll
3576 #ifdef FEAT_CLIPBOARD
3577 	     || (clip_star.state != SELECT_CLEARED
3578 						 && redrawing_for_callback > 0)
3579 #endif
3580 #ifdef FEAT_PROP_POPUP
3581 	     || popup_visible
3582 #endif
3583 	     )
3584 	return FAIL;
3585 
3586     /*
3587      * There are seven ways to insert lines:
3588      * 0. When in a vertically split window and t_CV isn't set, redraw the
3589      *    characters from ScreenLines[].
3590      * 1. Use T_CD (clear to end of display) if it exists and the result of
3591      *	  the insert is just empty lines
3592      * 2. Use T_CAL (insert multiple lines) if it exists and T_AL is not
3593      *	  present or line_count > 1. It looks better if we do all the inserts
3594      *	  at once.
3595      * 3. Use T_CDL (delete multiple lines) if it exists and the result of the
3596      *	  insert is just empty lines and T_CE is not present or line_count >
3597      *	  1.
3598      * 4. Use T_AL (insert line) if it exists.
3599      * 5. Use T_CE (erase line) if it exists and the result of the insert is
3600      *	  just empty lines.
3601      * 6. Use T_DL (delete line) if it exists and the result of the insert is
3602      *	  just empty lines.
3603      * 7. Use T_SR (scroll reverse) if it exists and inserting at row 0 and
3604      *	  the 'da' flag is not set or we have clear line capability.
3605      * 8. redraw the characters from ScreenLines[].
3606      *
3607      * Careful: In a hpterm scroll reverse doesn't work as expected, it moves
3608      * the scrollbar for the window. It does have insert line, use that if it
3609      * exists.
3610      */
3611     result_empty = (row + line_count >= end);
3612     if (wp != NULL && wp->w_width != Columns && *T_CSV == NUL)
3613 	type = USE_REDRAW;
3614     else if (can_clear(T_CD) && result_empty)
3615 	type = USE_T_CD;
3616     else if (*T_CAL != NUL && (line_count > 1 || *T_AL == NUL))
3617 	type = USE_T_CAL;
3618     else if (*T_CDL != NUL && result_empty && (line_count > 1 || !can_ce))
3619 	type = USE_T_CDL;
3620     else if (*T_AL != NUL)
3621 	type = USE_T_AL;
3622     else if (can_ce && result_empty)
3623 	type = USE_T_CE;
3624     else if (*T_DL != NUL && result_empty)
3625 	type = USE_T_DL;
3626     else if (*T_SR != NUL && row == 0 && (*T_DA == NUL || can_ce))
3627 	type = USE_T_SR;
3628     else
3629 	return FAIL;
3630 
3631     /*
3632      * For clearing the lines screen_del_lines() is used. This will also take
3633      * care of t_db if necessary.
3634      */
3635     if (type == USE_T_CD || type == USE_T_CDL ||
3636 					 type == USE_T_CE || type == USE_T_DL)
3637 	return screen_del_lines(off, row, line_count, end, FALSE, 0, wp);
3638 
3639     /*
3640      * If text is retained below the screen, first clear or delete as many
3641      * lines at the bottom of the window as are about to be inserted so that
3642      * the deleted lines won't later surface during a screen_del_lines.
3643      */
3644     if (*T_DB)
3645 	screen_del_lines(off, end - line_count, line_count, end, FALSE, 0, wp);
3646 
3647 #ifdef FEAT_CLIPBOARD
3648     // Remove a modeless selection when inserting lines halfway the screen
3649     // or not the full width of the screen.
3650     if (off + row > 0 || (wp != NULL && wp->w_width != Columns))
3651 	clip_clear_selection(&clip_star);
3652     else
3653 	clip_scroll_selection(-line_count);
3654 #endif
3655 
3656 #ifdef FEAT_GUI_HAIKU
3657     vim_lock_screen();
3658 #endif
3659 
3660 #ifdef FEAT_GUI
3661     // Don't update the GUI cursor here, ScreenLines[] is invalid until the
3662     // scrolling is actually carried out.
3663     gui_dont_update_cursor(row + off <= gui.cursor_row);
3664 #endif
3665 
3666     if (wp != NULL && wp->w_wincol != 0 && *T_CSV != NUL && *T_CCS == NUL)
3667 	cursor_col = wp->w_wincol;
3668 
3669     if (*T_CCS != NUL)	   // cursor relative to region
3670 	cursor_row = row;
3671     else
3672 	cursor_row = row + off;
3673 
3674     /*
3675      * Shift LineOffset[] line_count down to reflect the inserted lines.
3676      * Clear the inserted lines in ScreenLines[].
3677      */
3678     row += off;
3679     end += off;
3680     for (i = 0; i < line_count; ++i)
3681     {
3682 	if (wp != NULL && wp->w_width != Columns)
3683 	{
3684 	    // need to copy part of a line
3685 	    j = end - 1 - i;
3686 	    while ((j -= line_count) >= row)
3687 		linecopy(j + line_count, j, wp);
3688 	    j += line_count;
3689 	    if (can_clear((char_u *)" "))
3690 		lineclear(LineOffset[j] + wp->w_wincol, wp->w_width,
3691 								   clear_attr);
3692 	    else
3693 		lineinvalid(LineOffset[j] + wp->w_wincol, wp->w_width);
3694 	    LineWraps[j] = FALSE;
3695 	}
3696 	else
3697 	{
3698 	    j = end - 1 - i;
3699 	    temp = LineOffset[j];
3700 	    while ((j -= line_count) >= row)
3701 	    {
3702 		LineOffset[j + line_count] = LineOffset[j];
3703 		LineWraps[j + line_count] = LineWraps[j];
3704 	    }
3705 	    LineOffset[j + line_count] = temp;
3706 	    LineWraps[j + line_count] = FALSE;
3707 	    if (can_clear((char_u *)" "))
3708 		lineclear(temp, (int)Columns, clear_attr);
3709 	    else
3710 		lineinvalid(temp, (int)Columns);
3711 	}
3712     }
3713 
3714 #ifdef FEAT_GUI_HAIKU
3715     vim_unlock_screen();
3716 #endif
3717 
3718     screen_stop_highlight();
3719     windgoto(cursor_row, cursor_col);
3720     if (clear_attr != 0)
3721 	screen_start_highlight(clear_attr);
3722 
3723     // redraw the characters
3724     if (type == USE_REDRAW)
3725 	redraw_block(row, end, wp);
3726     else if (type == USE_T_CAL)
3727     {
3728 	term_append_lines(line_count);
3729 	screen_start();		// don't know where cursor is now
3730     }
3731     else
3732     {
3733 	for (i = 0; i < line_count; i++)
3734 	{
3735 	    if (type == USE_T_AL)
3736 	    {
3737 		if (i && cursor_row != 0)
3738 		    windgoto(cursor_row, cursor_col);
3739 		out_str(T_AL);
3740 	    }
3741 	    else  // type == USE_T_SR
3742 		out_str(T_SR);
3743 	    screen_start();	    // don't know where cursor is now
3744 	}
3745     }
3746 
3747     /*
3748      * With scroll-reverse and 'da' flag set we need to clear the lines that
3749      * have been scrolled down into the region.
3750      */
3751     if (type == USE_T_SR && *T_DA)
3752     {
3753 	for (i = 0; i < line_count; ++i)
3754 	{
3755 	    windgoto(off + i, cursor_col);
3756 	    out_str(T_CE);
3757 	    screen_start();	    // don't know where cursor is now
3758 	}
3759     }
3760 
3761 #ifdef FEAT_GUI
3762     gui_can_update_cursor();
3763     if (gui.in_use)
3764 	out_flush();	// always flush after a scroll
3765 #endif
3766     return OK;
3767 }
3768 
3769 /*
3770  * Delete lines on the screen and update ScreenLines[].
3771  * "end" is the line after the scrolled part. Normally it is Rows.
3772  * When scrolling region used "off" is the offset from the top for the region.
3773  * "row" and "end" are relative to the start of the region.
3774  *
3775  * Return OK for success, FAIL if the lines are not deleted.
3776  */
3777     int
3778 screen_del_lines(
3779     int		off,
3780     int		row,
3781     int		line_count,
3782     int		end,
3783     int		force,		// even when line_count > p_ttyscroll
3784     int		clear_attr,	// used for clearing lines
3785     win_T	*wp UNUSED)	// NULL or window to use width from
3786 {
3787     int		j;
3788     int		i;
3789     unsigned	temp;
3790     int		cursor_row;
3791     int		cursor_col = 0;
3792     int		cursor_end;
3793     int		result_empty;	// result is empty until end of region
3794     int		can_delete;	// deleting line codes can be used
3795     int		type;
3796 
3797     /*
3798      * FAIL if
3799      * - there is no valid screen
3800      * - the screen has to be redrawn completely
3801      * - the line count is less than one
3802      * - the line count is more than 'ttyscroll'
3803      * - redrawing for a callback and there is a modeless selection
3804      */
3805     if (!screen_valid(TRUE) || line_count <= 0
3806 					|| (!force && line_count > p_ttyscroll)
3807 #ifdef FEAT_CLIPBOARD
3808 	     || (clip_star.state != SELECT_CLEARED
3809 						 && redrawing_for_callback > 0)
3810 #endif
3811        )
3812 	return FAIL;
3813 
3814     /*
3815      * Check if the rest of the current region will become empty.
3816      */
3817     result_empty = row + line_count >= end;
3818 
3819     /*
3820      * We can delete lines only when 'db' flag not set or when 'ce' option
3821      * available.
3822      */
3823     can_delete = (*T_DB == NUL || can_clear(T_CE));
3824 
3825     /*
3826      * There are six ways to delete lines:
3827      * 0. When in a vertically split window and t_CV isn't set, redraw the
3828      *    characters from ScreenLines[].
3829      * 1. Use T_CD if it exists and the result is empty.
3830      * 2. Use newlines if row == 0 and count == 1 or T_CDL does not exist.
3831      * 3. Use T_CDL (delete multiple lines) if it exists and line_count > 1 or
3832      *	  none of the other ways work.
3833      * 4. Use T_CE (erase line) if the result is empty.
3834      * 5. Use T_DL (delete line) if it exists.
3835      * 6. redraw the characters from ScreenLines[].
3836      */
3837     if (wp != NULL && wp->w_width != Columns && *T_CSV == NUL)
3838 	type = USE_REDRAW;
3839     else if (can_clear(T_CD) && result_empty)
3840 	type = USE_T_CD;
3841 #if defined(__BEOS__) && defined(BEOS_DR8)
3842     /*
3843      * USE_NL does not seem to work in Terminal of DR8 so we set T_DB="" in
3844      * its internal termcap... this works okay for tests which test *T_DB !=
3845      * NUL.  It has the disadvantage that the user cannot use any :set t_*
3846      * command to get T_DB (back) to empty_option, only :set term=... will do
3847      * the trick...
3848      * Anyway, this hack will hopefully go away with the next OS release.
3849      * (Olaf Seibert)
3850      */
3851     else if (row == 0 && T_DB == empty_option
3852 					&& (line_count == 1 || *T_CDL == NUL))
3853 #else
3854     else if (row == 0 && (
3855 #ifndef AMIGA
3856 	// On the Amiga, somehow '\n' on the last line doesn't always scroll
3857 	// up, so use delete-line command
3858 			    line_count == 1 ||
3859 #endif
3860 						*T_CDL == NUL))
3861 #endif
3862 	type = USE_NL;
3863     else if (*T_CDL != NUL && line_count > 1 && can_delete)
3864 	type = USE_T_CDL;
3865     else if (can_clear(T_CE) && result_empty
3866 	    && (wp == NULL || wp->w_width == Columns))
3867 	type = USE_T_CE;
3868     else if (*T_DL != NUL && can_delete)
3869 	type = USE_T_DL;
3870     else if (*T_CDL != NUL && can_delete)
3871 	type = USE_T_CDL;
3872     else
3873 	return FAIL;
3874 
3875 #ifdef FEAT_CLIPBOARD
3876     // Remove a modeless selection when deleting lines halfway the screen or
3877     // not the full width of the screen.
3878     if (off + row > 0 || (wp != NULL && wp->w_width != Columns))
3879 	clip_clear_selection(&clip_star);
3880     else
3881 	clip_scroll_selection(line_count);
3882 #endif
3883 
3884 #ifdef FEAT_GUI
3885     // Don't update the GUI cursor here, ScreenLines[] is invalid until the
3886     // scrolling is actually carried out.
3887     gui_dont_update_cursor(gui.cursor_row >= row + off
3888 						&& gui.cursor_row < end + off);
3889 #endif
3890 
3891     if (wp != NULL && wp->w_wincol != 0 && *T_CSV != NUL && *T_CCS == NUL)
3892 	cursor_col = wp->w_wincol;
3893 
3894     if (*T_CCS != NUL)	    // cursor relative to region
3895     {
3896 	cursor_row = row;
3897 	cursor_end = end;
3898     }
3899     else
3900     {
3901 	cursor_row = row + off;
3902 	cursor_end = end + off;
3903     }
3904 
3905     /*
3906      * Now shift LineOffset[] line_count up to reflect the deleted lines.
3907      * Clear the inserted lines in ScreenLines[].
3908      */
3909     row += off;
3910     end += off;
3911     for (i = 0; i < line_count; ++i)
3912     {
3913 	if (wp != NULL && wp->w_width != Columns)
3914 	{
3915 	    // need to copy part of a line
3916 	    j = row + i;
3917 	    while ((j += line_count) <= end - 1)
3918 		linecopy(j - line_count, j, wp);
3919 	    j -= line_count;
3920 	    if (can_clear((char_u *)" "))
3921 		lineclear(LineOffset[j] + wp->w_wincol, wp->w_width,
3922 								   clear_attr);
3923 	    else
3924 		lineinvalid(LineOffset[j] + wp->w_wincol, wp->w_width);
3925 	    LineWraps[j] = FALSE;
3926 	}
3927 	else
3928 	{
3929 	    // whole width, moving the line pointers is faster
3930 	    j = row + i;
3931 	    temp = LineOffset[j];
3932 	    while ((j += line_count) <= end - 1)
3933 	    {
3934 		LineOffset[j - line_count] = LineOffset[j];
3935 		LineWraps[j - line_count] = LineWraps[j];
3936 	    }
3937 	    LineOffset[j - line_count] = temp;
3938 	    LineWraps[j - line_count] = FALSE;
3939 	    if (can_clear((char_u *)" "))
3940 		lineclear(temp, (int)Columns, clear_attr);
3941 	    else
3942 		lineinvalid(temp, (int)Columns);
3943 	}
3944     }
3945 
3946 #ifdef FEAT_GUI_HAIKU
3947     vim_unlock_screen();
3948 #endif
3949 
3950     if (screen_attr != clear_attr)
3951 	screen_stop_highlight();
3952     if (clear_attr != 0)
3953 	screen_start_highlight(clear_attr);
3954 
3955     // redraw the characters
3956     if (type == USE_REDRAW)
3957 	redraw_block(row, end, wp);
3958     else if (type == USE_T_CD)	// delete the lines
3959     {
3960 	windgoto(cursor_row, cursor_col);
3961 	out_str(T_CD);
3962 	screen_start();			// don't know where cursor is now
3963     }
3964     else if (type == USE_T_CDL)
3965     {
3966 	windgoto(cursor_row, cursor_col);
3967 	term_delete_lines(line_count);
3968 	screen_start();			// don't know where cursor is now
3969     }
3970     /*
3971      * Deleting lines at top of the screen or scroll region: Just scroll
3972      * the whole screen (scroll region) up by outputting newlines on the
3973      * last line.
3974      */
3975     else if (type == USE_NL)
3976     {
3977 	windgoto(cursor_end - 1, cursor_col);
3978 	for (i = line_count; --i >= 0; )
3979 	    out_char('\n');		// cursor will remain on same line
3980     }
3981     else
3982     {
3983 	for (i = line_count; --i >= 0; )
3984 	{
3985 	    if (type == USE_T_DL)
3986 	    {
3987 		windgoto(cursor_row, cursor_col);
3988 		out_str(T_DL);		// delete a line
3989 	    }
3990 	    else // type == USE_T_CE
3991 	    {
3992 		windgoto(cursor_row + i, cursor_col);
3993 		out_str(T_CE);		// erase a line
3994 	    }
3995 	    screen_start();		// don't know where cursor is now
3996 	}
3997     }
3998 
3999     /*
4000      * If the 'db' flag is set, we need to clear the lines that have been
4001      * scrolled up at the bottom of the region.
4002      */
4003     if (*T_DB && (type == USE_T_DL || type == USE_T_CDL))
4004     {
4005 	for (i = line_count; i > 0; --i)
4006 	{
4007 	    windgoto(cursor_end - i, cursor_col);
4008 	    out_str(T_CE);		// erase a line
4009 	    screen_start();		// don't know where cursor is now
4010 	}
4011     }
4012 
4013 #ifdef FEAT_GUI
4014     gui_can_update_cursor();
4015     if (gui.in_use)
4016 	out_flush();	// always flush after a scroll
4017 #endif
4018 
4019     return OK;
4020 }
4021 
4022 /*
4023  * Return TRUE when postponing displaying the mode message: when not redrawing
4024  * or inside a mapping.
4025  */
4026     int
4027 skip_showmode()
4028 {
4029     // Call char_avail() only when we are going to show something, because it
4030     // takes a bit of time.  redrawing() may also call char_avail_avail().
4031     if (global_busy
4032 	    || msg_silent != 0
4033 	    || !redrawing()
4034 	    || (char_avail() && !KeyTyped))
4035     {
4036 	redraw_mode = TRUE;		// show mode later
4037 	return TRUE;
4038     }
4039     return FALSE;
4040 }
4041 
4042 /*
4043  * Show the current mode and ruler.
4044  *
4045  * If clear_cmdline is TRUE, clear the rest of the cmdline.
4046  * If clear_cmdline is FALSE there may be a message there that needs to be
4047  * cleared only if a mode is shown.
4048  * If redraw_mode is TRUE show or clear the mode.
4049  * Return the length of the message (0 if no message).
4050  */
4051     int
4052 showmode(void)
4053 {
4054     int		need_clear;
4055     int		length = 0;
4056     int		do_mode;
4057     int		attr;
4058     int		nwr_save;
4059     int		sub_attr;
4060 
4061     do_mode = ((p_smd && msg_silent == 0)
4062 	    && ((State & INSERT)
4063 		|| restart_edit != NUL
4064 		|| VIsual_active));
4065     if (do_mode || reg_recording != 0)
4066     {
4067 	if (skip_showmode())
4068 	    return 0;		// show mode later
4069 
4070 	nwr_save = need_wait_return;
4071 
4072 	// wait a bit before overwriting an important message
4073 	check_for_delay(FALSE);
4074 
4075 	// if the cmdline is more than one line high, erase top lines
4076 	need_clear = clear_cmdline;
4077 	if (clear_cmdline && cmdline_row < Rows - 1)
4078 	    msg_clr_cmdline();			// will reset clear_cmdline
4079 
4080 	// Position on the last line in the window, column 0
4081 	msg_pos_mode();
4082 	cursor_off();
4083 	attr = HL_ATTR(HLF_CM);			// Highlight mode
4084 	if (do_mode)
4085 	{
4086 	    msg_puts_attr("--", attr);
4087 #if defined(FEAT_XIM)
4088 	    if (
4089 # ifdef FEAT_GUI_GTK
4090 		    preedit_get_status()
4091 # else
4092 		    im_get_status()
4093 # endif
4094 	       )
4095 # ifdef FEAT_GUI_GTK // most of the time, it's not XIM being used
4096 		msg_puts_attr(" IM", attr);
4097 # else
4098 		msg_puts_attr(" XIM", attr);
4099 # endif
4100 #endif
4101 	    // CTRL-X in Insert mode
4102 	    if (edit_submode != NULL && !shortmess(SHM_COMPLETIONMENU))
4103 	    {
4104 		// These messages can get long, avoid a wrap in a narrow
4105 		// window.  Prefer showing edit_submode_extra.
4106 		length = (Rows - msg_row) * Columns - 3;
4107 		if (edit_submode_extra != NULL)
4108 		    length -= vim_strsize(edit_submode_extra);
4109 		if (length > 0)
4110 		{
4111 		    if (edit_submode_pre != NULL)
4112 			length -= vim_strsize(edit_submode_pre);
4113 		    if (length - vim_strsize(edit_submode) > 0)
4114 		    {
4115 			if (edit_submode_pre != NULL)
4116 			    msg_puts_attr((char *)edit_submode_pre, attr);
4117 			msg_puts_attr((char *)edit_submode, attr);
4118 		    }
4119 		    if (edit_submode_extra != NULL)
4120 		    {
4121 			msg_puts_attr(" ", attr);  // add a space in between
4122 			if ((int)edit_submode_highl < (int)HLF_COUNT)
4123 			    sub_attr = HL_ATTR(edit_submode_highl);
4124 			else
4125 			    sub_attr = attr;
4126 			msg_puts_attr((char *)edit_submode_extra, sub_attr);
4127 		    }
4128 		}
4129 	    }
4130 	    else
4131 	    {
4132 		if (State & VREPLACE_FLAG)
4133 		    msg_puts_attr(_(" VREPLACE"), attr);
4134 		else if (State & REPLACE_FLAG)
4135 		    msg_puts_attr(_(" REPLACE"), attr);
4136 		else if (State & INSERT)
4137 		{
4138 #ifdef FEAT_RIGHTLEFT
4139 		    if (p_ri)
4140 			msg_puts_attr(_(" REVERSE"), attr);
4141 #endif
4142 		    msg_puts_attr(_(" INSERT"), attr);
4143 		}
4144 		else if (restart_edit == 'I' || restart_edit == 'A')
4145 		    msg_puts_attr(_(" (insert)"), attr);
4146 		else if (restart_edit == 'R')
4147 		    msg_puts_attr(_(" (replace)"), attr);
4148 		else if (restart_edit == 'V')
4149 		    msg_puts_attr(_(" (vreplace)"), attr);
4150 #ifdef FEAT_RIGHTLEFT
4151 		if (p_hkmap)
4152 		    msg_puts_attr(_(" Hebrew"), attr);
4153 #endif
4154 #ifdef FEAT_KEYMAP
4155 		if (State & LANGMAP)
4156 		{
4157 # ifdef FEAT_ARABIC
4158 		    if (curwin->w_p_arab)
4159 			msg_puts_attr(_(" Arabic"), attr);
4160 		    else
4161 # endif
4162 			if (get_keymap_str(curwin, (char_u *)" (%s)",
4163 							   NameBuff, MAXPATHL))
4164 			    msg_puts_attr((char *)NameBuff, attr);
4165 		}
4166 #endif
4167 		if ((State & INSERT) && p_paste)
4168 		    msg_puts_attr(_(" (paste)"), attr);
4169 
4170 		if (VIsual_active)
4171 		{
4172 		    char *p;
4173 
4174 		    // Don't concatenate separate words to avoid translation
4175 		    // problems.
4176 		    switch ((VIsual_select ? 4 : 0)
4177 			    + (VIsual_mode == Ctrl_V) * 2
4178 			    + (VIsual_mode == 'V'))
4179 		    {
4180 			case 0:	p = N_(" VISUAL"); break;
4181 			case 1: p = N_(" VISUAL LINE"); break;
4182 			case 2: p = N_(" VISUAL BLOCK"); break;
4183 			case 4: p = N_(" SELECT"); break;
4184 			case 5: p = N_(" SELECT LINE"); break;
4185 			default: p = N_(" SELECT BLOCK"); break;
4186 		    }
4187 		    msg_puts_attr(_(p), attr);
4188 		}
4189 		msg_puts_attr(" --", attr);
4190 	    }
4191 
4192 	    need_clear = TRUE;
4193 	}
4194 	if (reg_recording != 0
4195 		&& edit_submode == NULL)    // otherwise it gets too long
4196 	{
4197 	    recording_mode(attr);
4198 	    need_clear = TRUE;
4199 	}
4200 
4201 	mode_displayed = TRUE;
4202 	if (need_clear || clear_cmdline || redraw_mode)
4203 	    msg_clr_eos();
4204 	msg_didout = FALSE;		// overwrite this message
4205 	length = msg_col;
4206 	msg_col = 0;
4207 	need_wait_return = nwr_save;	// never ask for hit-return for this
4208     }
4209     else if (clear_cmdline && msg_silent == 0)
4210 	// Clear the whole command line.  Will reset "clear_cmdline".
4211 	msg_clr_cmdline();
4212     else if (redraw_mode)
4213     {
4214 	msg_pos_mode();
4215 	msg_clr_eos();
4216     }
4217 
4218 #ifdef FEAT_CMDL_INFO
4219     // In Visual mode the size of the selected area must be redrawn.
4220     if (VIsual_active)
4221 	clear_showcmd();
4222 
4223     // If the last window has no status line, the ruler is after the mode
4224     // message and must be redrawn
4225     if (redrawing() && lastwin->w_status_height == 0)
4226 	win_redr_ruler(lastwin, TRUE, FALSE);
4227 #endif
4228     redraw_cmdline = FALSE;
4229     redraw_mode = FALSE;
4230     clear_cmdline = FALSE;
4231 
4232     return length;
4233 }
4234 
4235 /*
4236  * Position for a mode message.
4237  */
4238     static void
4239 msg_pos_mode(void)
4240 {
4241     msg_col = 0;
4242     msg_row = Rows - 1;
4243 }
4244 
4245 /*
4246  * Delete mode message.  Used when ESC is typed which is expected to end
4247  * Insert mode (but Insert mode didn't end yet!).
4248  * Caller should check "mode_displayed".
4249  */
4250     void
4251 unshowmode(int force)
4252 {
4253     /*
4254      * Don't delete it right now, when not redrawing or inside a mapping.
4255      */
4256     if (!redrawing() || (!force && char_avail() && !KeyTyped))
4257 	redraw_cmdline = TRUE;		// delete mode later
4258     else
4259 	clearmode();
4260 }
4261 
4262 /*
4263  * Clear the mode message.
4264  */
4265     void
4266 clearmode(void)
4267 {
4268     int save_msg_row = msg_row;
4269     int save_msg_col = msg_col;
4270 
4271     msg_pos_mode();
4272     if (reg_recording != 0)
4273 	recording_mode(HL_ATTR(HLF_CM));
4274     msg_clr_eos();
4275 
4276     msg_col = save_msg_col;
4277     msg_row = save_msg_row;
4278 }
4279 
4280     static void
4281 recording_mode(int attr)
4282 {
4283     msg_puts_attr(_("recording"), attr);
4284     if (!shortmess(SHM_RECORDING))
4285     {
4286 	char s[4];
4287 
4288 	sprintf(s, " @%c", reg_recording);
4289 	msg_puts_attr(s, attr);
4290     }
4291 }
4292 
4293 /*
4294  * Draw the tab pages line at the top of the Vim window.
4295  */
4296     void
4297 draw_tabline(void)
4298 {
4299     int		tabcount = 0;
4300     tabpage_T	*tp;
4301     int		tabwidth;
4302     int		col = 0;
4303     int		scol = 0;
4304     int		attr;
4305     win_T	*wp;
4306     win_T	*cwp;
4307     int		wincount;
4308     int		modified;
4309     int		c;
4310     int		len;
4311     int		attr_sel = HL_ATTR(HLF_TPS);
4312     int		attr_nosel = HL_ATTR(HLF_TP);
4313     int		attr_fill = HL_ATTR(HLF_TPF);
4314     char_u	*p;
4315     int		room;
4316     int		use_sep_chars = (t_colors < 8
4317 #ifdef FEAT_GUI
4318 					    && !gui.in_use
4319 #endif
4320 #ifdef FEAT_TERMGUICOLORS
4321 					    && !p_tgc
4322 #endif
4323 					    );
4324 
4325     if (ScreenLines == NULL)
4326 	return;
4327     redraw_tabline = FALSE;
4328 
4329 #ifdef FEAT_GUI_TABLINE
4330     // Take care of a GUI tabline.
4331     if (gui_use_tabline())
4332     {
4333 	gui_update_tabline();
4334 	return;
4335     }
4336 #endif
4337 
4338     if (tabline_height() < 1)
4339 	return;
4340 
4341 #if defined(FEAT_STL_OPT)
4342     clear_TabPageIdxs();
4343 
4344     // Use the 'tabline' option if it's set.
4345     if (*p_tal != NUL)
4346     {
4347 	int	saved_did_emsg = did_emsg;
4348 
4349 	// Check for an error.  If there is one we would loop in redrawing the
4350 	// screen.  Avoid that by making 'tabline' empty.
4351 	did_emsg = FALSE;
4352 	win_redr_custom(NULL, FALSE);
4353 	if (did_emsg)
4354 	    set_string_option_direct((char_u *)"tabline", -1,
4355 					   (char_u *)"", OPT_FREE, SID_ERROR);
4356 	did_emsg |= saved_did_emsg;
4357     }
4358     else
4359 #endif
4360     {
4361 	FOR_ALL_TABPAGES(tp)
4362 	    ++tabcount;
4363 
4364 	tabwidth = (Columns - 1 + tabcount / 2) / tabcount;
4365 	if (tabwidth < 6)
4366 	    tabwidth = 6;
4367 
4368 	attr = attr_nosel;
4369 	tabcount = 0;
4370 	for (tp = first_tabpage; tp != NULL && col < Columns - 4;
4371 							     tp = tp->tp_next)
4372 	{
4373 	    scol = col;
4374 
4375 	    if (tp->tp_topframe == topframe)
4376 		attr = attr_sel;
4377 	    if (use_sep_chars && col > 0)
4378 		screen_putchar('|', 0, col++, attr);
4379 
4380 	    if (tp->tp_topframe != topframe)
4381 		attr = attr_nosel;
4382 
4383 	    screen_putchar(' ', 0, col++, attr);
4384 
4385 	    if (tp == curtab)
4386 	    {
4387 		cwp = curwin;
4388 		wp = firstwin;
4389 	    }
4390 	    else
4391 	    {
4392 		cwp = tp->tp_curwin;
4393 		wp = tp->tp_firstwin;
4394 	    }
4395 
4396 	    modified = FALSE;
4397 	    for (wincount = 0; wp != NULL; wp = wp->w_next, ++wincount)
4398 		if (bufIsChanged(wp->w_buffer))
4399 		    modified = TRUE;
4400 	    if (modified || wincount > 1)
4401 	    {
4402 		if (wincount > 1)
4403 		{
4404 		    vim_snprintf((char *)NameBuff, MAXPATHL, "%d", wincount);
4405 		    len = (int)STRLEN(NameBuff);
4406 		    if (col + len >= Columns - 3)
4407 			break;
4408 		    screen_puts_len(NameBuff, len, 0, col,
4409 #if defined(FEAT_SYN_HL)
4410 					 hl_combine_attr(attr, HL_ATTR(HLF_T))
4411 #else
4412 					 attr
4413 #endif
4414 					       );
4415 		    col += len;
4416 		}
4417 		if (modified)
4418 		    screen_puts_len((char_u *)"+", 1, 0, col++, attr);
4419 		screen_putchar(' ', 0, col++, attr);
4420 	    }
4421 
4422 	    room = scol - col + tabwidth - 1;
4423 	    if (room > 0)
4424 	    {
4425 		// Get buffer name in NameBuff[]
4426 		get_trans_bufname(cwp->w_buffer);
4427 		shorten_dir(NameBuff);
4428 		len = vim_strsize(NameBuff);
4429 		p = NameBuff;
4430 		if (has_mbyte)
4431 		    while (len > room)
4432 		    {
4433 			len -= ptr2cells(p);
4434 			MB_PTR_ADV(p);
4435 		    }
4436 		else if (len > room)
4437 		{
4438 		    p += len - room;
4439 		    len = room;
4440 		}
4441 		if (len > Columns - col - 1)
4442 		    len = Columns - col - 1;
4443 
4444 		screen_puts_len(p, (int)STRLEN(p), 0, col, attr);
4445 		col += len;
4446 	    }
4447 	    screen_putchar(' ', 0, col++, attr);
4448 
4449 	    // Store the tab page number in TabPageIdxs[], so that
4450 	    // jump_to_mouse() knows where each one is.
4451 	    ++tabcount;
4452 	    while (scol < col)
4453 		TabPageIdxs[scol++] = tabcount;
4454 	}
4455 
4456 	if (use_sep_chars)
4457 	    c = '_';
4458 	else
4459 	    c = ' ';
4460 	screen_fill(0, 1, col, (int)Columns, c, c, attr_fill);
4461 
4462 	// Put an "X" for closing the current tab if there are several.
4463 	if (first_tabpage->tp_next != NULL)
4464 	{
4465 	    screen_putchar('X', 0, (int)Columns - 1, attr_nosel);
4466 	    TabPageIdxs[Columns - 1] = -999;
4467 	}
4468     }
4469 
4470     // Reset the flag here again, in case evaluating 'tabline' causes it to be
4471     // set.
4472     redraw_tabline = FALSE;
4473 }
4474 
4475 /*
4476  * Get buffer name for "buf" into NameBuff[].
4477  * Takes care of special buffer names and translates special characters.
4478  */
4479     void
4480 get_trans_bufname(buf_T *buf)
4481 {
4482     if (buf_spname(buf) != NULL)
4483 	vim_strncpy(NameBuff, buf_spname(buf), MAXPATHL - 1);
4484     else
4485 	home_replace(buf, buf->b_fname, NameBuff, MAXPATHL, TRUE);
4486     trans_characters(NameBuff, MAXPATHL);
4487 }
4488 
4489 /*
4490  * Get the character to use in a status line.  Get its attributes in "*attr".
4491  */
4492     int
4493 fillchar_status(int *attr, win_T *wp)
4494 {
4495     int fill;
4496 
4497 #ifdef FEAT_TERMINAL
4498     if (bt_terminal(wp->w_buffer))
4499     {
4500 	if (wp == curwin)
4501 	{
4502 	    *attr = HL_ATTR(HLF_ST);
4503 	    fill = fill_stl;
4504 	}
4505 	else
4506 	{
4507 	    *attr = HL_ATTR(HLF_STNC);
4508 	    fill = fill_stlnc;
4509 	}
4510     }
4511     else
4512 #endif
4513     if (wp == curwin)
4514     {
4515 	*attr = HL_ATTR(HLF_S);
4516 	fill = fill_stl;
4517     }
4518     else
4519     {
4520 	*attr = HL_ATTR(HLF_SNC);
4521 	fill = fill_stlnc;
4522     }
4523     // Use fill when there is highlighting, and highlighting of current
4524     // window differs, or the fillchars differ, or this is not the
4525     // current window
4526     if (*attr != 0 && ((HL_ATTR(HLF_S) != HL_ATTR(HLF_SNC)
4527 			|| wp != curwin || ONE_WINDOW)
4528 		    || (fill_stl != fill_stlnc)))
4529 	return fill;
4530     if (wp == curwin)
4531 	return '^';
4532     return '=';
4533 }
4534 
4535 /*
4536  * Get the character to use in a separator between vertically split windows.
4537  * Get its attributes in "*attr".
4538  */
4539     int
4540 fillchar_vsep(int *attr)
4541 {
4542     *attr = HL_ATTR(HLF_C);
4543     if (*attr == 0 && fill_vert == ' ')
4544 	return '|';
4545     else
4546 	return fill_vert;
4547 }
4548 
4549 /*
4550  * Return TRUE if redrawing should currently be done.
4551  */
4552     int
4553 redrawing(void)
4554 {
4555 #ifdef FEAT_EVAL
4556     if (disable_redraw_for_testing)
4557 	return 0;
4558     else
4559 #endif
4560 	return ((!RedrawingDisabled
4561 #ifdef FEAT_EVAL
4562 		    || ignore_redraw_flag_for_testing
4563 #endif
4564 		) && !(p_lz && char_avail() && !KeyTyped && !do_redraw));
4565 }
4566 
4567 /*
4568  * Return TRUE if printing messages should currently be done.
4569  */
4570     int
4571 messaging(void)
4572 {
4573     return (!(p_lz && char_avail() && !KeyTyped));
4574 }
4575 
4576 /*
4577  * Compute columns for ruler and shown command. 'sc_col' is also used to
4578  * decide what the maximum length of a message on the status line can be.
4579  * If there is a status line for the last window, 'sc_col' is independent
4580  * of 'ru_col'.
4581  */
4582 
4583 #define COL_RULER 17	    // columns needed by standard ruler
4584 
4585     void
4586 comp_col(void)
4587 {
4588 #if defined(FEAT_CMDL_INFO)
4589     int last_has_status = (p_ls == 2 || (p_ls == 1 && !ONE_WINDOW));
4590 
4591     sc_col = 0;
4592     ru_col = 0;
4593     if (p_ru)
4594     {
4595 # ifdef FEAT_STL_OPT
4596 	ru_col = (ru_wid ? ru_wid : COL_RULER) + 1;
4597 # else
4598 	ru_col = COL_RULER + 1;
4599 # endif
4600 	// no last status line, adjust sc_col
4601 	if (!last_has_status)
4602 	    sc_col = ru_col;
4603     }
4604     if (p_sc)
4605     {
4606 	sc_col += SHOWCMD_COLS;
4607 	if (!p_ru || last_has_status)	    // no need for separating space
4608 	    ++sc_col;
4609     }
4610     sc_col = Columns - sc_col;
4611     ru_col = Columns - ru_col;
4612     if (sc_col <= 0)		// screen too narrow, will become a mess
4613 	sc_col = 1;
4614     if (ru_col <= 0)
4615 	ru_col = 1;
4616 #else
4617     sc_col = Columns;
4618     ru_col = Columns;
4619 #endif
4620 #ifdef FEAT_EVAL
4621     set_vim_var_nr(VV_ECHOSPACE, sc_col - 1);
4622 #endif
4623 }
4624 
4625 #if defined(FEAT_LINEBREAK) || defined(PROTO)
4626 /*
4627  * Return the width of the 'number' and 'relativenumber' column.
4628  * Caller may need to check if 'number' or 'relativenumber' is set.
4629  * Otherwise it depends on 'numberwidth' and the line count.
4630  */
4631     int
4632 number_width(win_T *wp)
4633 {
4634     int		n;
4635     linenr_T	lnum;
4636 
4637     if (wp->w_p_rnu && !wp->w_p_nu)
4638 	// cursor line shows "0"
4639 	lnum = wp->w_height;
4640     else
4641 	// cursor line shows absolute line number
4642 	lnum = wp->w_buffer->b_ml.ml_line_count;
4643 
4644     if (lnum == wp->w_nrwidth_line_count && wp->w_nuw_cached == wp->w_p_nuw)
4645 	return wp->w_nrwidth_width;
4646     wp->w_nrwidth_line_count = lnum;
4647 
4648     n = 0;
4649     do
4650     {
4651 	lnum /= 10;
4652 	++n;
4653     } while (lnum > 0);
4654 
4655     // 'numberwidth' gives the minimal width plus one
4656     if (n < wp->w_p_nuw - 1)
4657 	n = wp->w_p_nuw - 1;
4658 
4659 # ifdef FEAT_SIGNS
4660     // If 'signcolumn' is set to 'number' and there is a sign to display, then
4661     // the minimal width for the number column is 2.
4662     if (n < 2 && get_first_valid_sign(wp) != NULL
4663 	    && (*wp->w_p_scl == 'n' && *(wp->w_p_scl + 1) == 'u'))
4664 	n = 2;
4665 # endif
4666 
4667     wp->w_nrwidth_width = n;
4668     wp->w_nuw_cached = wp->w_p_nuw;
4669     return n;
4670 }
4671 #endif
4672 
4673 #if defined(FEAT_EVAL) || defined(PROTO)
4674 /*
4675  * Return the current cursor column. This is the actual position on the
4676  * screen. First column is 0.
4677  */
4678     int
4679 screen_screencol(void)
4680 {
4681     return screen_cur_col;
4682 }
4683 
4684 /*
4685  * Return the current cursor row. This is the actual position on the screen.
4686  * First row is 0.
4687  */
4688     int
4689 screen_screenrow(void)
4690 {
4691     return screen_cur_row;
4692 }
4693 #endif
4694 
4695 /*
4696  * Handle setting 'listchars' or 'fillchars'.
4697  * Returns error message, NULL if it's OK.
4698  */
4699     char *
4700 set_chars_option(char_u **varp)
4701 {
4702     int		round, i, len, entries;
4703     char_u	*p, *s;
4704     int		c1 = 0, c2 = 0, c3 = 0;
4705     struct charstab
4706     {
4707 	int	*cp;
4708 	char	*name;
4709     };
4710     static struct charstab filltab[] =
4711     {
4712 	{&fill_stl,	"stl"},
4713 	{&fill_stlnc,	"stlnc"},
4714 	{&fill_vert,	"vert"},
4715 	{&fill_fold,	"fold"},
4716 	{&fill_diff,	"diff"},
4717     };
4718     static struct charstab lcstab[] =
4719     {
4720 	{&lcs_eol,	"eol"},
4721 	{&lcs_ext,	"extends"},
4722 	{&lcs_nbsp,	"nbsp"},
4723 	{&lcs_prec,	"precedes"},
4724 	{&lcs_space,	"space"},
4725 	{&lcs_tab2,	"tab"},
4726 	{&lcs_trail,	"trail"},
4727 #ifdef FEAT_CONCEAL
4728 	{&lcs_conceal,	"conceal"},
4729 #else
4730 	{NULL,		"conceal"},
4731 #endif
4732     };
4733     struct charstab *tab;
4734 
4735     if (varp == &p_lcs)
4736     {
4737 	tab = lcstab;
4738 	entries = sizeof(lcstab) / sizeof(struct charstab);
4739     }
4740     else
4741     {
4742 	tab = filltab;
4743 	entries = sizeof(filltab) / sizeof(struct charstab);
4744     }
4745 
4746     // first round: check for valid value, second round: assign values
4747     for (round = 0; round <= 1; ++round)
4748     {
4749 	if (round > 0)
4750 	{
4751 	    // After checking that the value is valid: set defaults: space for
4752 	    // 'fillchars', NUL for 'listchars'
4753 	    for (i = 0; i < entries; ++i)
4754 		if (tab[i].cp != NULL)
4755 		    *(tab[i].cp) = (varp == &p_lcs ? NUL : ' ');
4756 
4757 	    if (varp == &p_lcs)
4758 	    {
4759 		lcs_tab1 = NUL;
4760 		lcs_tab3 = NUL;
4761 	    }
4762 	    else
4763 		fill_diff = '-';
4764 	}
4765 	p = *varp;
4766 	while (*p)
4767 	{
4768 	    for (i = 0; i < entries; ++i)
4769 	    {
4770 		len = (int)STRLEN(tab[i].name);
4771 		if (STRNCMP(p, tab[i].name, len) == 0
4772 			&& p[len] == ':'
4773 			&& p[len + 1] != NUL)
4774 		{
4775 		    c2 = c3 = 0;
4776 		    s = p + len + 1;
4777 		    c1 = mb_ptr2char_adv(&s);
4778 		    if (mb_char2cells(c1) > 1)
4779 			continue;
4780 		    if (tab[i].cp == &lcs_tab2)
4781 		    {
4782 			if (*s == NUL)
4783 			    continue;
4784 			c2 = mb_ptr2char_adv(&s);
4785 			if (mb_char2cells(c2) > 1)
4786 			    continue;
4787 			if (!(*s == ',' || *s == NUL))
4788 			{
4789 			    c3 = mb_ptr2char_adv(&s);
4790 			    if (mb_char2cells(c3) > 1)
4791 				continue;
4792 			}
4793 		    }
4794 
4795 		    if (*s == ',' || *s == NUL)
4796 		    {
4797 			if (round)
4798 			{
4799 			    if (tab[i].cp == &lcs_tab2)
4800 			    {
4801 				lcs_tab1 = c1;
4802 				lcs_tab2 = c2;
4803 				lcs_tab3 = c3;
4804 			    }
4805 			    else if (tab[i].cp != NULL)
4806 				*(tab[i].cp) = c1;
4807 
4808 			}
4809 			p = s;
4810 			break;
4811 		    }
4812 		}
4813 	    }
4814 
4815 	    if (i == entries)
4816 		return e_invarg;
4817 	    if (*p == ',')
4818 		++p;
4819 	}
4820     }
4821 
4822     return NULL;	// no error
4823 }
4824 
4825