xref: /vim-8.2.3635/src/change.c (revision ed37d9b3)
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  * change.c: functions related to changing text
12  */
13 
14 #include "vim.h"
15 
16 /*
17  * If the file is readonly, give a warning message with the first change.
18  * Don't do this for autocommands.
19  * Doesn't use emsg(), because it flushes the macro buffer.
20  * If we have undone all changes b_changed will be FALSE, but "b_did_warn"
21  * will be TRUE.
22  * "col" is the column for the message; non-zero when in insert mode and
23  * 'showmode' is on.
24  * Careful: may trigger autocommands that reload the buffer.
25  */
26     void
27 change_warning(int col)
28 {
29     static char *w_readonly = N_("W10: Warning: Changing a readonly file");
30 
31     if (curbuf->b_did_warn == FALSE
32 	    && curbufIsChanged() == 0
33 	    && !autocmd_busy
34 	    && curbuf->b_p_ro)
35     {
36 	++curbuf_lock;
37 	apply_autocmds(EVENT_FILECHANGEDRO, NULL, NULL, FALSE, curbuf);
38 	--curbuf_lock;
39 	if (!curbuf->b_p_ro)
40 	    return;
41 
42 	// Do what msg() does, but with a column offset if the warning should
43 	// be after the mode message.
44 	msg_start();
45 	if (msg_row == Rows - 1)
46 	    msg_col = col;
47 	msg_source(HL_ATTR(HLF_W));
48 	msg_puts_attr(_(w_readonly), HL_ATTR(HLF_W) | MSG_HIST);
49 #ifdef FEAT_EVAL
50 	set_vim_var_string(VV_WARNINGMSG, (char_u *)_(w_readonly), -1);
51 #endif
52 	msg_clr_eos();
53 	(void)msg_end();
54 	if (msg_silent == 0 && !silent_mode
55 #ifdef FEAT_EVAL
56 		&& time_for_testing != 1
57 #endif
58 		)
59 	{
60 	    out_flush();
61 	    ui_delay(1002L, TRUE); // give the user time to think about it
62 	}
63 	curbuf->b_did_warn = TRUE;
64 	redraw_cmdline = FALSE;	// don't redraw and erase the message
65 	if (msg_row < Rows - 1)
66 	    showmode();
67     }
68 }
69 
70 /*
71  * Call this function when something in the current buffer is changed.
72  *
73  * Most often called through changed_bytes() and changed_lines(), which also
74  * mark the area of the display to be redrawn.
75  *
76  * Careful: may trigger autocommands that reload the buffer.
77  */
78     void
79 changed(void)
80 {
81 #if defined(FEAT_XIM) && defined(FEAT_GUI_GTK)
82     if (p_imst == IM_ON_THE_SPOT)
83     {
84 	// The text of the preediting area is inserted, but this doesn't
85 	// mean a change of the buffer yet.  That is delayed until the
86 	// text is committed. (this means preedit becomes empty)
87 	if (im_is_preediting() && !xim_changed_while_preediting)
88 	    return;
89 	xim_changed_while_preediting = FALSE;
90     }
91 #endif
92 
93     if (!curbuf->b_changed)
94     {
95 	int	save_msg_scroll = msg_scroll;
96 
97 	// Give a warning about changing a read-only file.  This may also
98 	// check-out the file, thus change "curbuf"!
99 	change_warning(0);
100 
101 	// Create a swap file if that is wanted.
102 	// Don't do this for "nofile" and "nowrite" buffer types.
103 	if (curbuf->b_may_swap
104 #ifdef FEAT_QUICKFIX
105 		&& !bt_dontwrite(curbuf)
106 #endif
107 		)
108 	{
109 	    int save_need_wait_return = need_wait_return;
110 
111 	    need_wait_return = FALSE;
112 	    ml_open_file(curbuf);
113 
114 	    // The ml_open_file() can cause an ATTENTION message.
115 	    // Wait two seconds, to make sure the user reads this unexpected
116 	    // message.  Since we could be anywhere, call wait_return() now,
117 	    // and don't let the emsg() set msg_scroll.
118 	    if (need_wait_return && emsg_silent == 0)
119 	    {
120 		out_flush();
121 		ui_delay(2002L, TRUE);
122 		wait_return(TRUE);
123 		msg_scroll = save_msg_scroll;
124 	    }
125 	    else
126 		need_wait_return = save_need_wait_return;
127 	}
128 	changed_internal();
129     }
130     ++CHANGEDTICK(curbuf);
131 
132 #ifdef FEAT_SEARCH_EXTRA
133     // If a pattern is highlighted, the position may now be invalid.
134     highlight_match = FALSE;
135 #endif
136 }
137 
138 /*
139  * Internal part of changed(), no user interaction.
140  * Also used for recovery.
141  */
142     void
143 changed_internal(void)
144 {
145     curbuf->b_changed = TRUE;
146     ml_setflags(curbuf);
147     check_status(curbuf);
148     redraw_tabline = TRUE;
149 #ifdef FEAT_TITLE
150     need_maketitle = TRUE;	    // set window title later
151 #endif
152 }
153 
154 #ifdef FEAT_EVAL
155 static long next_listener_id = 0;
156 
157 /*
158  * Check if the change at "lnum" is above or overlaps with an existing
159  * change. If above then flush changes and invoke listeners.
160  * Returns TRUE if the change was merged.
161  */
162     static int
163 check_recorded_changes(
164 	buf_T		*buf,
165 	linenr_T	lnum,
166 	linenr_T	lnume,
167 	long		xtra)
168 {
169     if (buf->b_recorded_changes != NULL && xtra != 0)
170     {
171 	listitem_T *li;
172 	linenr_T    prev_lnum;
173 	linenr_T    prev_lnume;
174 
175 	FOR_ALL_LIST_ITEMS(buf->b_recorded_changes, li)
176 	{
177 	    prev_lnum = (linenr_T)dict_get_number(
178 				      li->li_tv.vval.v_dict, (char_u *)"lnum");
179 	    prev_lnume = (linenr_T)dict_get_number(
180 				       li->li_tv.vval.v_dict, (char_u *)"end");
181 	    if (prev_lnum >= lnum || prev_lnum > lnume || prev_lnume >= lnum)
182 	    {
183 		// the current change is going to make the line number in
184 		// the older change invalid, flush now
185 		invoke_listeners(curbuf);
186 		break;
187 	    }
188 	}
189     }
190     return FALSE;
191 }
192 
193 /*
194  * Record a change for listeners added with listener_add().
195  * Always for the current buffer.
196  */
197     static void
198 may_record_change(
199     linenr_T	lnum,
200     colnr_T	col,
201     linenr_T	lnume,
202     long	xtra)
203 {
204     dict_T	*dict;
205 
206     if (curbuf->b_listener == NULL)
207 	return;
208 
209     // If the new change is going to change the line numbers in already listed
210     // changes, then flush.
211     if (check_recorded_changes(curbuf, lnum, lnume, xtra))
212 	return;
213 
214     if (curbuf->b_recorded_changes == NULL)
215     {
216 	curbuf->b_recorded_changes = list_alloc();
217 	if (curbuf->b_recorded_changes == NULL)  // out of memory
218 	    return;
219 	++curbuf->b_recorded_changes->lv_refcount;
220 	curbuf->b_recorded_changes->lv_lock = VAR_FIXED;
221     }
222 
223     dict = dict_alloc();
224     if (dict == NULL)
225 	return;
226     dict_add_number(dict, "lnum", (varnumber_T)lnum);
227     dict_add_number(dict, "end", (varnumber_T)lnume);
228     dict_add_number(dict, "added", (varnumber_T)xtra);
229     dict_add_number(dict, "col", (varnumber_T)col + 1);
230 
231     list_append_dict(curbuf->b_recorded_changes, dict);
232 }
233 
234 /*
235  * listener_add() function
236  */
237     void
238 f_listener_add(typval_T *argvars, typval_T *rettv)
239 {
240     callback_T	callback;
241     listener_T	*lnr;
242     buf_T	*buf = curbuf;
243 
244     callback = get_callback(&argvars[0]);
245     if (callback.cb_name == NULL)
246 	return;
247 
248     if (argvars[1].v_type != VAR_UNKNOWN)
249     {
250 	buf = get_buf_arg(&argvars[1]);
251 	if (buf == NULL)
252 	{
253 	    free_callback(&callback);
254 	    return;
255 	}
256     }
257 
258     lnr = ALLOC_CLEAR_ONE(listener_T);
259     if (lnr == NULL)
260     {
261 	free_callback(&callback);
262 	return;
263     }
264     lnr->lr_next = buf->b_listener;
265     buf->b_listener = lnr;
266 
267     set_callback(&lnr->lr_callback, &callback);
268 
269     lnr->lr_id = ++next_listener_id;
270     rettv->vval.v_number = lnr->lr_id;
271 }
272 
273 /*
274  * listener_flush() function
275  */
276     void
277 f_listener_flush(typval_T *argvars, typval_T *rettv UNUSED)
278 {
279     buf_T	*buf = curbuf;
280 
281     if (argvars[0].v_type != VAR_UNKNOWN)
282     {
283 	buf = get_buf_arg(&argvars[0]);
284 	if (buf == NULL)
285 	    return;
286     }
287     invoke_listeners(buf);
288 }
289 
290 /*
291  * listener_remove() function
292  */
293     void
294 f_listener_remove(typval_T *argvars, typval_T *rettv)
295 {
296     listener_T	*lnr;
297     listener_T	*next;
298     listener_T	*prev;
299     int		id = tv_get_number(argvars);
300     buf_T	*buf;
301 
302     FOR_ALL_BUFFERS(buf)
303     {
304 	prev = NULL;
305 	for (lnr = buf->b_listener; lnr != NULL; lnr = next)
306 	{
307 	    next = lnr->lr_next;
308 	    if (lnr->lr_id == id)
309 	    {
310 		if (prev != NULL)
311 		    prev->lr_next = lnr->lr_next;
312 		else
313 		    buf->b_listener = lnr->lr_next;
314 		free_callback(&lnr->lr_callback);
315 		vim_free(lnr);
316 		rettv->vval.v_number = 1;
317 		return;
318 	    }
319 	    prev = lnr;
320 	}
321     }
322 }
323 
324 /*
325  * Called before inserting a line above "lnum"/"lnum3" or deleting line "lnum"
326  * to "lnume".
327  */
328     void
329 may_invoke_listeners(buf_T *buf, linenr_T lnum, linenr_T lnume, int added)
330 {
331     check_recorded_changes(buf, lnum, lnume, added);
332 }
333 
334 /*
335  * Called when a sequence of changes is done: invoke listeners added with
336  * listener_add().
337  */
338     void
339 invoke_listeners(buf_T *buf)
340 {
341     listener_T	*lnr;
342     typval_T	rettv;
343     typval_T	argv[6];
344     listitem_T	*li;
345     linenr_T	start = MAXLNUM;
346     linenr_T	end = 0;
347     linenr_T	added = 0;
348     int		save_updating_screen = updating_screen;
349     static int	recursive = FALSE;
350 
351     if (buf->b_recorded_changes == NULL  // nothing changed
352 	    || buf->b_listener == NULL   // no listeners
353 	    || recursive)		 // already busy
354 	return;
355     recursive = TRUE;
356 
357     // Block messages on channels from being handled, so that they don't make
358     // text changes here.
359     ++updating_screen;
360 
361     argv[0].v_type = VAR_NUMBER;
362     argv[0].vval.v_number = buf->b_fnum; // a:bufnr
363 
364     FOR_ALL_LIST_ITEMS(buf->b_recorded_changes, li)
365     {
366 	varnumber_T lnum;
367 
368 	lnum = dict_get_number(li->li_tv.vval.v_dict, (char_u *)"lnum");
369 	if (start > lnum)
370 	    start = lnum;
371 	lnum = dict_get_number(li->li_tv.vval.v_dict, (char_u *)"end");
372 	if (end < lnum)
373 	    end = lnum;
374 	added += dict_get_number(li->li_tv.vval.v_dict, (char_u *)"added");
375     }
376     argv[1].v_type = VAR_NUMBER;
377     argv[1].vval.v_number = start;
378     argv[2].v_type = VAR_NUMBER;
379     argv[2].vval.v_number = end;
380     argv[3].v_type = VAR_NUMBER;
381     argv[3].vval.v_number = added;
382 
383     argv[4].v_type = VAR_LIST;
384     argv[4].vval.v_list = buf->b_recorded_changes;
385     ++textwinlock;
386 
387     for (lnr = buf->b_listener; lnr != NULL; lnr = lnr->lr_next)
388     {
389 	call_callback(&lnr->lr_callback, -1, &rettv, 5, argv);
390 	clear_tv(&rettv);
391     }
392 
393     --textwinlock;
394     list_unref(buf->b_recorded_changes);
395     buf->b_recorded_changes = NULL;
396 
397     if (save_updating_screen)
398 	updating_screen = TRUE;
399     else
400 	after_updating_screen(TRUE);
401     recursive = FALSE;
402 }
403 
404 /*
405  * Remove all listeners associated with "buf".
406  */
407     void
408 remove_listeners(buf_T *buf)
409 {
410     listener_T	*lnr;
411     listener_T	*next;
412 
413     for (lnr = buf->b_listener; lnr != NULL; lnr = next)
414     {
415 	next = lnr->lr_next;
416 	free_callback(&lnr->lr_callback);
417 	vim_free(lnr);
418     }
419     buf->b_listener = NULL;
420 }
421 #endif
422 
423 /*
424  * Common code for when a change was made.
425  * See changed_lines() for the arguments.
426  * Careful: may trigger autocommands that reload the buffer.
427  */
428     static void
429 changed_common(
430     linenr_T	lnum,
431     colnr_T	col,
432     linenr_T	lnume,
433     long	xtra)
434 {
435     win_T	*wp;
436     tabpage_T	*tp;
437     int		i;
438 #ifdef FEAT_JUMPLIST
439     int		cols;
440     pos_T	*p;
441     int		add;
442 #endif
443 
444     // mark the buffer as modified
445     changed();
446 
447 #ifdef FEAT_EVAL
448     may_record_change(lnum, col, lnume, xtra);
449 #endif
450 #ifdef FEAT_DIFF
451     if (curwin->w_p_diff && diff_internal())
452 	curtab->tp_diff_update = TRUE;
453 #endif
454 
455     // set the '. mark
456     if (!cmdmod.keepjumps)
457     {
458 	curbuf->b_last_change.lnum = lnum;
459 	curbuf->b_last_change.col = col;
460 
461 #ifdef FEAT_JUMPLIST
462 	// Create a new entry if a new undo-able change was started or we
463 	// don't have an entry yet.
464 	if (curbuf->b_new_change || curbuf->b_changelistlen == 0)
465 	{
466 	    if (curbuf->b_changelistlen == 0)
467 		add = TRUE;
468 	    else
469 	    {
470 		// Don't create a new entry when the line number is the same
471 		// as the last one and the column is not too far away.  Avoids
472 		// creating many entries for typing "xxxxx".
473 		p = &curbuf->b_changelist[curbuf->b_changelistlen - 1];
474 		if (p->lnum != lnum)
475 		    add = TRUE;
476 		else
477 		{
478 		    cols = comp_textwidth(FALSE);
479 		    if (cols == 0)
480 			cols = 79;
481 		    add = (p->col + cols < col || col + cols < p->col);
482 		}
483 	    }
484 	    if (add)
485 	    {
486 		// This is the first of a new sequence of undo-able changes
487 		// and it's at some distance of the last change.  Use a new
488 		// position in the changelist.
489 		curbuf->b_new_change = FALSE;
490 
491 		if (curbuf->b_changelistlen == JUMPLISTSIZE)
492 		{
493 		    // changelist is full: remove oldest entry
494 		    curbuf->b_changelistlen = JUMPLISTSIZE - 1;
495 		    mch_memmove(curbuf->b_changelist, curbuf->b_changelist + 1,
496 					  sizeof(pos_T) * (JUMPLISTSIZE - 1));
497 		    FOR_ALL_TAB_WINDOWS(tp, wp)
498 		    {
499 			// Correct position in changelist for other windows on
500 			// this buffer.
501 			if (wp->w_buffer == curbuf && wp->w_changelistidx > 0)
502 			    --wp->w_changelistidx;
503 		    }
504 		}
505 		FOR_ALL_TAB_WINDOWS(tp, wp)
506 		{
507 		    // For other windows, if the position in the changelist is
508 		    // at the end it stays at the end.
509 		    if (wp->w_buffer == curbuf
510 			    && wp->w_changelistidx == curbuf->b_changelistlen)
511 			++wp->w_changelistidx;
512 		}
513 		++curbuf->b_changelistlen;
514 	    }
515 	}
516 	curbuf->b_changelist[curbuf->b_changelistlen - 1] =
517 							curbuf->b_last_change;
518 	// The current window is always after the last change, so that "g,"
519 	// takes you back to it.
520 	curwin->w_changelistidx = curbuf->b_changelistlen;
521 #endif
522     }
523 
524     FOR_ALL_TAB_WINDOWS(tp, wp)
525     {
526 	if (wp->w_buffer == curbuf)
527 	{
528 	    // Mark this window to be redrawn later.
529 	    if (wp->w_redr_type < VALID)
530 		wp->w_redr_type = VALID;
531 
532 	    // Check if a change in the buffer has invalidated the cached
533 	    // values for the cursor.
534 #ifdef FEAT_FOLDING
535 	    // Update the folds for this window.  Can't postpone this, because
536 	    // a following operator might work on the whole fold: ">>dd".
537 	    foldUpdate(wp, lnum, lnume + xtra - 1);
538 
539 	    // The change may cause lines above or below the change to become
540 	    // included in a fold.  Set lnum/lnume to the first/last line that
541 	    // might be displayed differently.
542 	    // Set w_cline_folded here as an efficient way to update it when
543 	    // inserting lines just above a closed fold.
544 	    i = hasFoldingWin(wp, lnum, &lnum, NULL, FALSE, NULL);
545 	    if (wp->w_cursor.lnum == lnum)
546 		wp->w_cline_folded = i;
547 	    i = hasFoldingWin(wp, lnume, NULL, &lnume, FALSE, NULL);
548 	    if (wp->w_cursor.lnum == lnume)
549 		wp->w_cline_folded = i;
550 
551 	    // If the changed line is in a range of previously folded lines,
552 	    // compare with the first line in that range.
553 	    if (wp->w_cursor.lnum <= lnum)
554 	    {
555 		i = find_wl_entry(wp, lnum);
556 		if (i >= 0 && wp->w_cursor.lnum > wp->w_lines[i].wl_lnum)
557 		    changed_line_abv_curs_win(wp);
558 	    }
559 #endif
560 	    if (wp->w_cursor.lnum > lnum)
561 		changed_line_abv_curs_win(wp);
562 	    else if (wp->w_cursor.lnum == lnum && wp->w_cursor.col >= col)
563 		changed_cline_bef_curs_win(wp);
564 	    if (wp->w_botline >= lnum)
565 	    {
566 		// Assume that botline doesn't change (inserted lines make
567 		// other lines scroll down below botline).
568 		approximate_botline_win(wp);
569 	    }
570 
571 	    // Check if any w_lines[] entries have become invalid.
572 	    // For entries below the change: Correct the lnums for
573 	    // inserted/deleted lines.  Makes it possible to stop displaying
574 	    // after the change.
575 	    for (i = 0; i < wp->w_lines_valid; ++i)
576 		if (wp->w_lines[i].wl_valid)
577 		{
578 		    if (wp->w_lines[i].wl_lnum >= lnum)
579 		    {
580 			if (wp->w_lines[i].wl_lnum < lnume)
581 			{
582 			    // line included in change
583 			    wp->w_lines[i].wl_valid = FALSE;
584 			}
585 			else if (xtra != 0)
586 			{
587 			    // line below change
588 			    wp->w_lines[i].wl_lnum += xtra;
589 #ifdef FEAT_FOLDING
590 			    wp->w_lines[i].wl_lastlnum += xtra;
591 #endif
592 			}
593 		    }
594 #ifdef FEAT_FOLDING
595 		    else if (wp->w_lines[i].wl_lastlnum >= lnum)
596 		    {
597 			// change somewhere inside this range of folded lines,
598 			// may need to be redrawn
599 			wp->w_lines[i].wl_valid = FALSE;
600 		    }
601 #endif
602 		}
603 
604 #ifdef FEAT_FOLDING
605 	    // Take care of side effects for setting w_topline when folds have
606 	    // changed.  Esp. when the buffer was changed in another window.
607 	    if (hasAnyFolding(wp))
608 		set_topline(wp, wp->w_topline);
609 #endif
610 	    // Relative numbering may require updating more.
611 	    if (wp->w_p_rnu)
612 		redraw_win_later(wp, SOME_VALID);
613 #ifdef FEAT_SYN_HL
614 	    // Cursor line highlighting probably need to be updated with
615 	    // "VALID" if it's below the change.
616 	    // If the cursor line is inside the change we need to redraw more.
617 	    if (wp->w_p_cul)
618 	    {
619 		if (xtra == 0)
620 		    redraw_win_later(wp, VALID);
621 		else if (lnum <= wp->w_last_cursorline)
622 		    redraw_win_later(wp, SOME_VALID);
623 	    }
624 #endif
625 	}
626     }
627 
628     // Call update_screen() later, which checks out what needs to be redrawn,
629     // since it notices b_mod_set and then uses b_mod_*.
630     if (must_redraw < VALID)
631 	must_redraw = VALID;
632 
633     // when the cursor line is changed always trigger CursorMoved
634     if (lnum <= curwin->w_cursor.lnum
635 		 && lnume + (xtra < 0 ? -xtra : xtra) > curwin->w_cursor.lnum)
636 	last_cursormoved.lnum = 0;
637 }
638 
639     static void
640 changedOneline(buf_T *buf, linenr_T lnum)
641 {
642     if (buf->b_mod_set)
643     {
644 	// find the maximum area that must be redisplayed
645 	if (lnum < buf->b_mod_top)
646 	    buf->b_mod_top = lnum;
647 	else if (lnum >= buf->b_mod_bot)
648 	    buf->b_mod_bot = lnum + 1;
649     }
650     else
651     {
652 	// set the area that must be redisplayed to one line
653 	buf->b_mod_set = TRUE;
654 	buf->b_mod_top = lnum;
655 	buf->b_mod_bot = lnum + 1;
656 	buf->b_mod_xlines = 0;
657     }
658 }
659 
660 /*
661  * Changed bytes within a single line for the current buffer.
662  * - marks the windows on this buffer to be redisplayed
663  * - marks the buffer changed by calling changed()
664  * - invalidates cached values
665  * Careful: may trigger autocommands that reload the buffer.
666  */
667     void
668 changed_bytes(linenr_T lnum, colnr_T col)
669 {
670     changedOneline(curbuf, lnum);
671     changed_common(lnum, col, lnum + 1, 0L);
672 
673 #ifdef FEAT_DIFF
674     // Diff highlighting in other diff windows may need to be updated too.
675     if (curwin->w_p_diff)
676     {
677 	win_T	    *wp;
678 	linenr_T    wlnum;
679 
680 	FOR_ALL_WINDOWS(wp)
681 	    if (wp->w_p_diff && wp != curwin)
682 	    {
683 		redraw_win_later(wp, VALID);
684 		wlnum = diff_lnum_win(lnum, wp);
685 		if (wlnum > 0)
686 		    changedOneline(wp->w_buffer, wlnum);
687 	    }
688     }
689 #endif
690 }
691 
692 /*
693  * Like changed_bytes() but also adjust text properties for "added" bytes.
694  * When "added" is negative text was deleted.
695  */
696     static void
697 inserted_bytes(linenr_T lnum, colnr_T col, int added UNUSED)
698 {
699 #ifdef FEAT_PROP_POPUP
700     if (curbuf->b_has_textprop && added != 0)
701 	adjust_prop_columns(lnum, col, added, 0);
702 #endif
703 
704     changed_bytes(lnum, col);
705 }
706 
707 /*
708  * Appended "count" lines below line "lnum" in the current buffer.
709  * Must be called AFTER the change and after mark_adjust().
710  * Takes care of marking the buffer to be redrawn and sets the changed flag.
711  */
712     void
713 appended_lines(linenr_T lnum, long count)
714 {
715     changed_lines(lnum + 1, 0, lnum + 1, count);
716 }
717 
718 /*
719  * Like appended_lines(), but adjust marks first.
720  */
721     void
722 appended_lines_mark(linenr_T lnum, long count)
723 {
724     // Skip mark_adjust when adding a line after the last one, there can't
725     // be marks there. But it's still needed in diff mode.
726     if (lnum + count < curbuf->b_ml.ml_line_count
727 #ifdef FEAT_DIFF
728 	    || curwin->w_p_diff
729 #endif
730 	)
731 	mark_adjust(lnum + 1, (linenr_T)MAXLNUM, count, 0L);
732     changed_lines(lnum + 1, 0, lnum + 1, count);
733 }
734 
735 /*
736  * Deleted "count" lines at line "lnum" in the current buffer.
737  * Must be called AFTER the change and after mark_adjust().
738  * Takes care of marking the buffer to be redrawn and sets the changed flag.
739  */
740     void
741 deleted_lines(linenr_T lnum, long count)
742 {
743     changed_lines(lnum, 0, lnum + count, -count);
744 }
745 
746 /*
747  * Like deleted_lines(), but adjust marks first.
748  * Make sure the cursor is on a valid line before calling, a GUI callback may
749  * be triggered to display the cursor.
750  */
751     void
752 deleted_lines_mark(linenr_T lnum, long count)
753 {
754     mark_adjust(lnum, (linenr_T)(lnum + count - 1), (long)MAXLNUM, -count);
755     changed_lines(lnum, 0, lnum + count, -count);
756 }
757 
758 /*
759  * Marks the area to be redrawn after a change.
760  */
761     static void
762 changed_lines_buf(
763     buf_T	*buf,
764     linenr_T	lnum,	    // first line with change
765     linenr_T	lnume,	    // line below last changed line
766     long	xtra)	    // number of extra lines (negative when deleting)
767 {
768     if (buf->b_mod_set)
769     {
770 	// find the maximum area that must be redisplayed
771 	if (lnum < buf->b_mod_top)
772 	    buf->b_mod_top = lnum;
773 	if (lnum < buf->b_mod_bot)
774 	{
775 	    // adjust old bot position for xtra lines
776 	    buf->b_mod_bot += xtra;
777 	    if (buf->b_mod_bot < lnum)
778 		buf->b_mod_bot = lnum;
779 	}
780 	if (lnume + xtra > buf->b_mod_bot)
781 	    buf->b_mod_bot = lnume + xtra;
782 	buf->b_mod_xlines += xtra;
783     }
784     else
785     {
786 	// set the area that must be redisplayed
787 	buf->b_mod_set = TRUE;
788 	buf->b_mod_top = lnum;
789 	buf->b_mod_bot = lnume + xtra;
790 	buf->b_mod_xlines = xtra;
791     }
792 }
793 
794 /*
795  * Changed lines for the current buffer.
796  * Must be called AFTER the change and after mark_adjust().
797  * - mark the buffer changed by calling changed()
798  * - mark the windows on this buffer to be redisplayed
799  * - invalidate cached values
800  * "lnum" is the first line that needs displaying, "lnume" the first line
801  * below the changed lines (BEFORE the change).
802  * When only inserting lines, "lnum" and "lnume" are equal.
803  * Takes care of calling changed() and updating b_mod_*.
804  * Careful: may trigger autocommands that reload the buffer.
805  */
806     void
807 changed_lines(
808     linenr_T	lnum,	    // first line with change
809     colnr_T	col,	    // column in first line with change
810     linenr_T	lnume,	    // line below last changed line
811     long	xtra)	    // number of extra lines (negative when deleting)
812 {
813     changed_lines_buf(curbuf, lnum, lnume, xtra);
814 
815 #ifdef FEAT_DIFF
816     if (xtra == 0 && curwin->w_p_diff && !diff_internal())
817     {
818 	// When the number of lines doesn't change then mark_adjust() isn't
819 	// called and other diff buffers still need to be marked for
820 	// displaying.
821 	win_T	    *wp;
822 	linenr_T    wlnum;
823 
824 	FOR_ALL_WINDOWS(wp)
825 	    if (wp->w_p_diff && wp != curwin)
826 	    {
827 		redraw_win_later(wp, VALID);
828 		wlnum = diff_lnum_win(lnum, wp);
829 		if (wlnum > 0)
830 		    changed_lines_buf(wp->w_buffer, wlnum,
831 						    lnume - lnum + wlnum, 0L);
832 	    }
833     }
834 #endif
835 
836     changed_common(lnum, col, lnume, xtra);
837 }
838 
839 /*
840  * Called when the changed flag must be reset for buffer "buf".
841  * When "ff" is TRUE also reset 'fileformat'.
842  * When "always_inc_changedtick" is TRUE b:changedtick is incremented also when
843  * the changed flag was off.
844  */
845     void
846 unchanged(buf_T *buf, int ff, int always_inc_changedtick)
847 {
848     if (buf->b_changed || (ff && file_ff_differs(buf, FALSE)))
849     {
850 	buf->b_changed = 0;
851 	ml_setflags(buf);
852 	if (ff)
853 	    save_file_ff(buf);
854 	check_status(buf);
855 	redraw_tabline = TRUE;
856 #ifdef FEAT_TITLE
857 	need_maketitle = TRUE;	    // set window title later
858 #endif
859 	++CHANGEDTICK(buf);
860     }
861     else if (always_inc_changedtick)
862 	++CHANGEDTICK(buf);
863 #ifdef FEAT_NETBEANS_INTG
864     netbeans_unmodified(buf);
865 #endif
866 }
867 
868 /*
869  * Save the current values of 'fileformat' and 'fileencoding', so that we know
870  * the file must be considered changed when the value is different.
871  */
872     void
873 save_file_ff(buf_T *buf)
874 {
875     buf->b_start_ffc = *buf->b_p_ff;
876     buf->b_start_eol = buf->b_p_eol;
877     buf->b_start_bomb = buf->b_p_bomb;
878 
879     // Only use free/alloc when necessary, they take time.
880     if (buf->b_start_fenc == NULL
881 			     || STRCMP(buf->b_start_fenc, buf->b_p_fenc) != 0)
882     {
883 	vim_free(buf->b_start_fenc);
884 	buf->b_start_fenc = vim_strsave(buf->b_p_fenc);
885     }
886 }
887 
888 /*
889  * Return TRUE if 'fileformat' and/or 'fileencoding' has a different value
890  * from when editing started (save_file_ff() called).
891  * Also when 'endofline' was changed and 'binary' is set, or when 'bomb' was
892  * changed and 'binary' is not set.
893  * Also when 'endofline' was changed and 'fixeol' is not set.
894  * When "ignore_empty" is true don't consider a new, empty buffer to be
895  * changed.
896  */
897     int
898 file_ff_differs(buf_T *buf, int ignore_empty)
899 {
900     // In a buffer that was never loaded the options are not valid.
901     if (buf->b_flags & BF_NEVERLOADED)
902 	return FALSE;
903     if (ignore_empty
904 	    && (buf->b_flags & BF_NEW)
905 	    && buf->b_ml.ml_line_count == 1
906 	    && *ml_get_buf(buf, (linenr_T)1, FALSE) == NUL)
907 	return FALSE;
908     if (buf->b_start_ffc != *buf->b_p_ff)
909 	return TRUE;
910     if ((buf->b_p_bin || !buf->b_p_fixeol) && buf->b_start_eol != buf->b_p_eol)
911 	return TRUE;
912     if (!buf->b_p_bin && buf->b_start_bomb != buf->b_p_bomb)
913 	return TRUE;
914     if (buf->b_start_fenc == NULL)
915 	return (*buf->b_p_fenc != NUL);
916     return (STRCMP(buf->b_start_fenc, buf->b_p_fenc) != 0);
917 }
918 
919 /*
920  * Insert string "p" at the cursor position.  Stops at a NUL byte.
921  * Handles Replace mode and multi-byte characters.
922  */
923     void
924 ins_bytes(char_u *p)
925 {
926     ins_bytes_len(p, (int)STRLEN(p));
927 }
928 
929 /*
930  * Insert string "p" with length "len" at the cursor position.
931  * Handles Replace mode and multi-byte characters.
932  */
933     void
934 ins_bytes_len(char_u *p, int len)
935 {
936     int		i;
937     int		n;
938 
939     if (has_mbyte)
940 	for (i = 0; i < len; i += n)
941 	{
942 	    if (enc_utf8)
943 		// avoid reading past p[len]
944 		n = utfc_ptr2len_len(p + i, len - i);
945 	    else
946 		n = (*mb_ptr2len)(p + i);
947 	    ins_char_bytes(p + i, n);
948 	}
949     else
950 	for (i = 0; i < len; ++i)
951 	    ins_char(p[i]);
952 }
953 
954 /*
955  * Insert or replace a single character at the cursor position.
956  * When in REPLACE or VREPLACE mode, replace any existing character.
957  * Caller must have prepared for undo.
958  * For multi-byte characters we get the whole character, the caller must
959  * convert bytes to a character.
960  */
961     void
962 ins_char(int c)
963 {
964     char_u	buf[MB_MAXBYTES + 1];
965     int		n = (*mb_char2bytes)(c, buf);
966 
967     // When "c" is 0x100, 0x200, etc. we don't want to insert a NUL byte.
968     // Happens for CTRL-Vu9900.
969     if (buf[0] == 0)
970 	buf[0] = '\n';
971 
972     ins_char_bytes(buf, n);
973 }
974 
975     void
976 ins_char_bytes(char_u *buf, int charlen)
977 {
978     int		c = buf[0];
979     int		newlen;		// nr of bytes inserted
980     int		oldlen;		// nr of bytes deleted (0 when not replacing)
981     char_u	*p;
982     char_u	*newp;
983     char_u	*oldp;
984     int		linelen;	// length of old line including NUL
985     colnr_T	col;
986     linenr_T	lnum = curwin->w_cursor.lnum;
987     int		i;
988 
989     // Break tabs if needed.
990     if (virtual_active() && curwin->w_cursor.coladd > 0)
991 	coladvance_force(getviscol());
992 
993     col = curwin->w_cursor.col;
994     oldp = ml_get(lnum);
995     linelen = (int)STRLEN(oldp) + 1;
996 
997     // The lengths default to the values for when not replacing.
998     oldlen = 0;
999     newlen = charlen;
1000 
1001     if (State & REPLACE_FLAG)
1002     {
1003 	if (State & VREPLACE_FLAG)
1004 	{
1005 	    colnr_T	new_vcol = 0;   // init for GCC
1006 	    colnr_T	vcol;
1007 	    int		old_list;
1008 
1009 	    // Disable 'list' temporarily, unless 'cpo' contains the 'L' flag.
1010 	    // Returns the old value of list, so when finished,
1011 	    // curwin->w_p_list should be set back to this.
1012 	    old_list = curwin->w_p_list;
1013 	    if (old_list && vim_strchr(p_cpo, CPO_LISTWM) == NULL)
1014 		curwin->w_p_list = FALSE;
1015 
1016 	    // In virtual replace mode each character may replace one or more
1017 	    // characters (zero if it's a TAB).  Count the number of bytes to
1018 	    // be deleted to make room for the new character, counting screen
1019 	    // cells.  May result in adding spaces to fill a gap.
1020 	    getvcol(curwin, &curwin->w_cursor, NULL, &vcol, NULL);
1021 	    new_vcol = vcol + chartabsize(buf, vcol);
1022 	    while (oldp[col + oldlen] != NUL && vcol < new_vcol)
1023 	    {
1024 		vcol += chartabsize(oldp + col + oldlen, vcol);
1025 		// Don't need to remove a TAB that takes us to the right
1026 		// position.
1027 		if (vcol > new_vcol && oldp[col + oldlen] == TAB)
1028 		    break;
1029 		oldlen += (*mb_ptr2len)(oldp + col + oldlen);
1030 		// Deleted a bit too much, insert spaces.
1031 		if (vcol > new_vcol)
1032 		    newlen += vcol - new_vcol;
1033 	    }
1034 	    curwin->w_p_list = old_list;
1035 	}
1036 	else if (oldp[col] != NUL)
1037 	{
1038 	    // normal replace
1039 	    oldlen = (*mb_ptr2len)(oldp + col);
1040 	}
1041 
1042 
1043 	// Push the replaced bytes onto the replace stack, so that they can be
1044 	// put back when BS is used.  The bytes of a multi-byte character are
1045 	// done the other way around, so that the first byte is popped off
1046 	// first (it tells the byte length of the character).
1047 	replace_push(NUL);
1048 	for (i = 0; i < oldlen; ++i)
1049 	{
1050 	    if (has_mbyte)
1051 		i += replace_push_mb(oldp + col + i) - 1;
1052 	    else
1053 		replace_push(oldp[col + i]);
1054 	}
1055     }
1056 
1057     newp = alloc(linelen + newlen - oldlen);
1058     if (newp == NULL)
1059 	return;
1060 
1061     // Copy bytes before the cursor.
1062     if (col > 0)
1063 	mch_memmove(newp, oldp, (size_t)col);
1064 
1065     // Copy bytes after the changed character(s).
1066     p = newp + col;
1067     if (linelen > col + oldlen)
1068 	mch_memmove(p + newlen, oldp + col + oldlen,
1069 					    (size_t)(linelen - col - oldlen));
1070 
1071     // Insert or overwrite the new character.
1072     mch_memmove(p, buf, charlen);
1073     i = charlen;
1074 
1075     // Fill with spaces when necessary.
1076     while (i < newlen)
1077 	p[i++] = ' ';
1078 
1079     // Replace the line in the buffer.
1080     ml_replace(lnum, newp, FALSE);
1081 
1082     // mark the buffer as changed and prepare for displaying
1083     inserted_bytes(lnum, col, newlen - oldlen);
1084 
1085     // If we're in Insert or Replace mode and 'showmatch' is set, then briefly
1086     // show the match for right parens and braces.
1087     if (p_sm && (State & INSERT)
1088 	    && msg_silent == 0
1089 	    && !ins_compl_active())
1090     {
1091 	if (has_mbyte)
1092 	    showmatch(mb_ptr2char(buf));
1093 	else
1094 	    showmatch(c);
1095     }
1096 
1097 #ifdef FEAT_RIGHTLEFT
1098     if (!p_ri || (State & REPLACE_FLAG))
1099 #endif
1100     {
1101 	// Normal insert: move cursor right
1102 	curwin->w_cursor.col += charlen;
1103     }
1104 
1105     // TODO: should try to update w_row here, to avoid recomputing it later.
1106 }
1107 
1108 /*
1109  * Insert a string at the cursor position.
1110  * Note: Does NOT handle Replace mode.
1111  * Caller must have prepared for undo.
1112  */
1113     void
1114 ins_str(char_u *s)
1115 {
1116     char_u	*oldp, *newp;
1117     int		newlen = (int)STRLEN(s);
1118     int		oldlen;
1119     colnr_T	col;
1120     linenr_T	lnum = curwin->w_cursor.lnum;
1121 
1122     if (virtual_active() && curwin->w_cursor.coladd > 0)
1123 	coladvance_force(getviscol());
1124 
1125     col = curwin->w_cursor.col;
1126     oldp = ml_get(lnum);
1127     oldlen = (int)STRLEN(oldp);
1128 
1129     newp = alloc(oldlen + newlen + 1);
1130     if (newp == NULL)
1131 	return;
1132     if (col > 0)
1133 	mch_memmove(newp, oldp, (size_t)col);
1134     mch_memmove(newp + col, s, (size_t)newlen);
1135     mch_memmove(newp + col + newlen, oldp + col, (size_t)(oldlen - col + 1));
1136     ml_replace(lnum, newp, FALSE);
1137     inserted_bytes(lnum, col, newlen);
1138     curwin->w_cursor.col += newlen;
1139 }
1140 
1141 /*
1142  * Delete one character under the cursor.
1143  * If "fixpos" is TRUE, don't leave the cursor on the NUL after the line.
1144  * Caller must have prepared for undo.
1145  *
1146  * return FAIL for failure, OK otherwise
1147  */
1148     int
1149 del_char(int fixpos)
1150 {
1151     if (has_mbyte)
1152     {
1153 	// Make sure the cursor is at the start of a character.
1154 	mb_adjust_cursor();
1155 	if (*ml_get_cursor() == NUL)
1156 	    return FAIL;
1157 	return del_chars(1L, fixpos);
1158     }
1159     return del_bytes(1L, fixpos, TRUE);
1160 }
1161 
1162 /*
1163  * Like del_bytes(), but delete characters instead of bytes.
1164  */
1165     int
1166 del_chars(long count, int fixpos)
1167 {
1168     long	bytes = 0;
1169     long	i;
1170     char_u	*p;
1171     int		l;
1172 
1173     p = ml_get_cursor();
1174     for (i = 0; i < count && *p != NUL; ++i)
1175     {
1176 	l = (*mb_ptr2len)(p);
1177 	bytes += l;
1178 	p += l;
1179     }
1180     return del_bytes(bytes, fixpos, TRUE);
1181 }
1182 
1183 /*
1184  * Delete "count" bytes under the cursor.
1185  * If "fixpos" is TRUE, don't leave the cursor on the NUL after the line.
1186  * Caller must have prepared for undo.
1187  *
1188  * Return FAIL for failure, OK otherwise.
1189  */
1190     int
1191 del_bytes(
1192     long	count,
1193     int		fixpos_arg,
1194     int		use_delcombine UNUSED)	    // 'delcombine' option applies
1195 {
1196     char_u	*oldp, *newp;
1197     colnr_T	oldlen;
1198     colnr_T	newlen;
1199     linenr_T	lnum = curwin->w_cursor.lnum;
1200     colnr_T	col = curwin->w_cursor.col;
1201     int		alloc_newp;
1202     long	movelen;
1203     int		fixpos = fixpos_arg;
1204 
1205     oldp = ml_get(lnum);
1206     oldlen = (int)STRLEN(oldp);
1207 
1208     // Can't do anything when the cursor is on the NUL after the line.
1209     if (col >= oldlen)
1210 	return FAIL;
1211 
1212     // If "count" is zero there is nothing to do.
1213     if (count == 0)
1214 	return OK;
1215 
1216     // If "count" is negative the caller must be doing something wrong.
1217     if (count < 1)
1218     {
1219 	siemsg("E292: Invalid count for del_bytes(): %ld", count);
1220 	return FAIL;
1221     }
1222 
1223     // If 'delcombine' is set and deleting (less than) one character, only
1224     // delete the last combining character.
1225     if (p_deco && use_delcombine && enc_utf8
1226 					 && utfc_ptr2len(oldp + col) >= count)
1227     {
1228 	int	cc[MAX_MCO];
1229 	int	n;
1230 
1231 	(void)utfc_ptr2char(oldp + col, cc);
1232 	if (cc[0] != NUL)
1233 	{
1234 	    // Find the last composing char, there can be several.
1235 	    n = col;
1236 	    do
1237 	    {
1238 		col = n;
1239 		count = utf_ptr2len(oldp + n);
1240 		n += count;
1241 	    } while (UTF_COMPOSINGLIKE(oldp + col, oldp + n));
1242 	    fixpos = 0;
1243 	}
1244     }
1245 
1246     // When count is too big, reduce it.
1247     movelen = (long)oldlen - (long)col - count + 1; // includes trailing NUL
1248     if (movelen <= 1)
1249     {
1250 	// If we just took off the last character of a non-blank line, and
1251 	// fixpos is TRUE, we don't want to end up positioned at the NUL,
1252 	// unless "restart_edit" is set or 'virtualedit' contains "onemore".
1253 	if (col > 0 && fixpos && restart_edit == 0
1254 					      && (ve_flags & VE_ONEMORE) == 0)
1255 	{
1256 	    --curwin->w_cursor.col;
1257 	    curwin->w_cursor.coladd = 0;
1258 	    if (has_mbyte)
1259 		curwin->w_cursor.col -=
1260 			    (*mb_head_off)(oldp, oldp + curwin->w_cursor.col);
1261 	}
1262 	count = oldlen - col;
1263 	movelen = 1;
1264     }
1265     newlen = oldlen - count;
1266 
1267     // If the old line has been allocated the deletion can be done in the
1268     // existing line. Otherwise a new line has to be allocated
1269     // Can't do this when using Netbeans, because we would need to invoke
1270     // netbeans_removed(), which deallocates the line.  Let ml_replace() take
1271     // care of notifying Netbeans.
1272 #ifdef FEAT_NETBEANS_INTG
1273     if (netbeans_active())
1274 	alloc_newp = TRUE;
1275     else
1276 #endif
1277 	alloc_newp = !ml_line_alloced();    // check if oldp was allocated
1278     if (!alloc_newp)
1279 	newp = oldp;			    // use same allocated memory
1280     else
1281     {					    // need to allocate a new line
1282 	newp = alloc(newlen + 1);
1283 	if (newp == NULL)
1284 	    return FAIL;
1285 	mch_memmove(newp, oldp, (size_t)col);
1286     }
1287     mch_memmove(newp + col, oldp + col + count, (size_t)movelen);
1288     if (alloc_newp)
1289 	ml_replace(lnum, newp, FALSE);
1290 #ifdef FEAT_PROP_POPUP
1291     else
1292     {
1293 	// Also move any following text properties.
1294 	if (oldlen + 1 < curbuf->b_ml.ml_line_len)
1295 	    mch_memmove(newp + newlen + 1, oldp + oldlen + 1,
1296 			       (size_t)curbuf->b_ml.ml_line_len - oldlen - 1);
1297 	curbuf->b_ml.ml_line_len -= count;
1298     }
1299 #endif
1300 
1301     // mark the buffer as changed and prepare for displaying
1302     inserted_bytes(lnum, col, -count);
1303 
1304     return OK;
1305 }
1306 
1307 /*
1308  * open_line: Add a new line below or above the current line.
1309  *
1310  * For VREPLACE mode, we only add a new line when we get to the end of the
1311  * file, otherwise we just start replacing the next line.
1312  *
1313  * Caller must take care of undo.  Since VREPLACE may affect any number of
1314  * lines however, it may call u_save_cursor() again when starting to change a
1315  * new line.
1316  * "flags": OPENLINE_DELSPACES	delete spaces after cursor
1317  *	    OPENLINE_DO_COM	format comments
1318  *	    OPENLINE_KEEPTRAIL	keep trailing spaces
1319  *	    OPENLINE_MARKFIX	adjust mark positions after the line break
1320  *	    OPENLINE_COM_LIST	format comments with list or 2nd line indent
1321  *
1322  * "second_line_indent": indent for after ^^D in Insert mode or if flag
1323  *			  OPENLINE_COM_LIST
1324  *
1325  * Return OK for success, FAIL for failure
1326  */
1327     int
1328 open_line(
1329     int		dir,		// FORWARD or BACKWARD
1330     int		flags,
1331     int		second_line_indent)
1332 {
1333     char_u	*saved_line;		// copy of the original line
1334     char_u	*next_line = NULL;	// copy of the next line
1335     char_u	*p_extra = NULL;	// what goes to next line
1336     int		less_cols = 0;		// less columns for mark in new line
1337     int		less_cols_off = 0;	// columns to skip for mark adjust
1338     pos_T	old_cursor;		// old cursor position
1339     int		newcol = 0;		// new cursor column
1340     int		newindent = 0;		// auto-indent of the new line
1341     int		n;
1342     int		trunc_line = FALSE;	// truncate current line afterwards
1343     int		retval = FAIL;		// return value
1344     int		extra_len = 0;		// length of p_extra string
1345     int		lead_len;		// length of comment leader
1346     char_u	*lead_flags;	// position in 'comments' for comment leader
1347     char_u	*leader = NULL;		// copy of comment leader
1348     char_u	*allocated = NULL;	// allocated memory
1349     char_u	*p;
1350     int		saved_char = NUL;	// init for GCC
1351     pos_T	*pos;
1352 #ifdef FEAT_SMARTINDENT
1353     int		do_si = (!p_paste && curbuf->b_p_si
1354 # ifdef FEAT_CINDENT
1355 					&& !curbuf->b_p_cin
1356 # endif
1357 # ifdef FEAT_EVAL
1358 					&& *curbuf->b_p_inde == NUL
1359 # endif
1360 			);
1361     int		no_si = FALSE;		// reset did_si afterwards
1362     int		first_char = NUL;	// init for GCC
1363 #endif
1364 #if defined(FEAT_LISP) || defined(FEAT_CINDENT)
1365     int		vreplace_mode;
1366 #endif
1367     int		did_append;		// appended a new line
1368     int		saved_pi = curbuf->b_p_pi; // copy of preserveindent setting
1369 
1370     // make a copy of the current line so we can mess with it
1371     saved_line = vim_strsave(ml_get_curline());
1372     if (saved_line == NULL)	    // out of memory!
1373 	return FALSE;
1374 
1375     if (State & VREPLACE_FLAG)
1376     {
1377 	// With VREPLACE we make a copy of the next line, which we will be
1378 	// starting to replace.  First make the new line empty and let vim play
1379 	// with the indenting and comment leader to its heart's content.  Then
1380 	// we grab what it ended up putting on the new line, put back the
1381 	// original line, and call ins_char() to put each new character onto
1382 	// the line, replacing what was there before and pushing the right
1383 	// stuff onto the replace stack.  -- webb.
1384 	if (curwin->w_cursor.lnum < orig_line_count)
1385 	    next_line = vim_strsave(ml_get(curwin->w_cursor.lnum + 1));
1386 	else
1387 	    next_line = vim_strsave((char_u *)"");
1388 	if (next_line == NULL)	    // out of memory!
1389 	    goto theend;
1390 
1391 	// In VREPLACE mode, a NL replaces the rest of the line, and starts
1392 	// replacing the next line, so push all of the characters left on the
1393 	// line onto the replace stack.  We'll push any other characters that
1394 	// might be replaced at the start of the next line (due to autoindent
1395 	// etc) a bit later.
1396 	replace_push(NUL);  // Call twice because BS over NL expects it
1397 	replace_push(NUL);
1398 	p = saved_line + curwin->w_cursor.col;
1399 	while (*p != NUL)
1400 	{
1401 	    if (has_mbyte)
1402 		p += replace_push_mb(p);
1403 	    else
1404 		replace_push(*p++);
1405 	}
1406 	saved_line[curwin->w_cursor.col] = NUL;
1407     }
1408 
1409     if ((State & INSERT) && !(State & VREPLACE_FLAG))
1410     {
1411 	p_extra = saved_line + curwin->w_cursor.col;
1412 #ifdef FEAT_SMARTINDENT
1413 	if (do_si)		// need first char after new line break
1414 	{
1415 	    p = skipwhite(p_extra);
1416 	    first_char = *p;
1417 	}
1418 #endif
1419 	extra_len = (int)STRLEN(p_extra);
1420 	saved_char = *p_extra;
1421 	*p_extra = NUL;
1422     }
1423 
1424     u_clearline();		// cannot do "U" command when adding lines
1425 #ifdef FEAT_SMARTINDENT
1426     did_si = FALSE;
1427 #endif
1428     ai_col = 0;
1429 
1430     // If we just did an auto-indent, then we didn't type anything on
1431     // the prior line, and it should be truncated.  Do this even if 'ai' is not
1432     // set because automatically inserting a comment leader also sets did_ai.
1433     if (dir == FORWARD && did_ai)
1434 	trunc_line = TRUE;
1435 
1436     // If 'autoindent' and/or 'smartindent' is set, try to figure out what
1437     // indent to use for the new line.
1438     if (curbuf->b_p_ai
1439 #ifdef FEAT_SMARTINDENT
1440 			|| do_si
1441 #endif
1442 					    )
1443     {
1444 	// count white space on current line
1445 #ifdef FEAT_VARTABS
1446 	newindent = get_indent_str_vtab(saved_line, curbuf->b_p_ts,
1447 						 curbuf->b_p_vts_array, FALSE);
1448 #else
1449 	newindent = get_indent_str(saved_line, (int)curbuf->b_p_ts, FALSE);
1450 #endif
1451 	if (newindent == 0 && !(flags & OPENLINE_COM_LIST))
1452 	    newindent = second_line_indent; // for ^^D command in insert mode
1453 
1454 #ifdef FEAT_SMARTINDENT
1455 	// Do smart indenting.
1456 	// In insert/replace mode (only when dir == FORWARD)
1457 	// we may move some text to the next line. If it starts with '{'
1458 	// don't add an indent. Fixes inserting a NL before '{' in line
1459 	//	"if (condition) {"
1460 	if (!trunc_line && do_si && *saved_line != NUL
1461 				    && (p_extra == NULL || first_char != '{'))
1462 	{
1463 	    char_u  *ptr;
1464 	    char_u  last_char;
1465 
1466 	    old_cursor = curwin->w_cursor;
1467 	    ptr = saved_line;
1468 	    if (flags & OPENLINE_DO_COM)
1469 		lead_len = get_leader_len(ptr, NULL, FALSE, TRUE);
1470 	    else
1471 		lead_len = 0;
1472 	    if (dir == FORWARD)
1473 	    {
1474 		// Skip preprocessor directives, unless they are
1475 		// recognised as comments.
1476 		if ( lead_len == 0 && ptr[0] == '#')
1477 		{
1478 		    while (ptr[0] == '#' && curwin->w_cursor.lnum > 1)
1479 			ptr = ml_get(--curwin->w_cursor.lnum);
1480 		    newindent = get_indent();
1481 		}
1482 		if (flags & OPENLINE_DO_COM)
1483 		    lead_len = get_leader_len(ptr, NULL, FALSE, TRUE);
1484 		else
1485 		    lead_len = 0;
1486 		if (lead_len > 0)
1487 		{
1488 		    // This case gets the following right:
1489 		    //	    /*
1490 		    //	     * A comment (read '\' as '/').
1491 		    //	     */
1492 		    // #define IN_THE_WAY
1493 		    //	    This should line up here;
1494 		    p = skipwhite(ptr);
1495 		    if (p[0] == '/' && p[1] == '*')
1496 			p++;
1497 		    if (p[0] == '*')
1498 		    {
1499 			for (p++; *p; p++)
1500 			{
1501 			    if (p[0] == '/' && p[-1] == '*')
1502 			    {
1503 				// End of C comment, indent should line up
1504 				// with the line containing the start of
1505 				// the comment
1506 				curwin->w_cursor.col = (colnr_T)(p - ptr);
1507 				if ((pos = findmatch(NULL, NUL)) != NULL)
1508 				{
1509 				    curwin->w_cursor.lnum = pos->lnum;
1510 				    newindent = get_indent();
1511 				}
1512 			    }
1513 			}
1514 		    }
1515 		}
1516 		else	// Not a comment line
1517 		{
1518 		    // Find last non-blank in line
1519 		    p = ptr + STRLEN(ptr) - 1;
1520 		    while (p > ptr && VIM_ISWHITE(*p))
1521 			--p;
1522 		    last_char = *p;
1523 
1524 		    // find the character just before the '{' or ';'
1525 		    if (last_char == '{' || last_char == ';')
1526 		    {
1527 			if (p > ptr)
1528 			    --p;
1529 			while (p > ptr && VIM_ISWHITE(*p))
1530 			    --p;
1531 		    }
1532 		    // Try to catch lines that are split over multiple
1533 		    // lines.  eg:
1534 		    //	    if (condition &&
1535 		    //			condition) {
1536 		    //		Should line up here!
1537 		    //	    }
1538 		    if (*p == ')')
1539 		    {
1540 			curwin->w_cursor.col = (colnr_T)(p - ptr);
1541 			if ((pos = findmatch(NULL, '(')) != NULL)
1542 			{
1543 			    curwin->w_cursor.lnum = pos->lnum;
1544 			    newindent = get_indent();
1545 			    ptr = ml_get_curline();
1546 			}
1547 		    }
1548 		    // If last character is '{' do indent, without
1549 		    // checking for "if" and the like.
1550 		    if (last_char == '{')
1551 		    {
1552 			did_si = TRUE;	// do indent
1553 			no_si = TRUE;	// don't delete it when '{' typed
1554 		    }
1555 		    // Look for "if" and the like, use 'cinwords'.
1556 		    // Don't do this if the previous line ended in ';' or
1557 		    // '}'.
1558 		    else if (last_char != ';' && last_char != '}'
1559 						       && cin_is_cinword(ptr))
1560 			did_si = TRUE;
1561 		}
1562 	    }
1563 	    else // dir == BACKWARD
1564 	    {
1565 		// Skip preprocessor directives, unless they are
1566 		// recognised as comments.
1567 		if (lead_len == 0 && ptr[0] == '#')
1568 		{
1569 		    int was_backslashed = FALSE;
1570 
1571 		    while ((ptr[0] == '#' || was_backslashed) &&
1572 			 curwin->w_cursor.lnum < curbuf->b_ml.ml_line_count)
1573 		    {
1574 			if (*ptr && ptr[STRLEN(ptr) - 1] == '\\')
1575 			    was_backslashed = TRUE;
1576 			else
1577 			    was_backslashed = FALSE;
1578 			ptr = ml_get(++curwin->w_cursor.lnum);
1579 		    }
1580 		    if (was_backslashed)
1581 			newindent = 0;	    // Got to end of file
1582 		    else
1583 			newindent = get_indent();
1584 		}
1585 		p = skipwhite(ptr);
1586 		if (*p == '}')	    // if line starts with '}': do indent
1587 		    did_si = TRUE;
1588 		else		    // can delete indent when '{' typed
1589 		    can_si_back = TRUE;
1590 	    }
1591 	    curwin->w_cursor = old_cursor;
1592 	}
1593 	if (do_si)
1594 	    can_si = TRUE;
1595 #endif // FEAT_SMARTINDENT
1596 
1597 	did_ai = TRUE;
1598     }
1599 
1600     // Find out if the current line starts with a comment leader.
1601     // This may then be inserted in front of the new line.
1602     end_comment_pending = NUL;
1603     if (flags & OPENLINE_DO_COM)
1604 	lead_len = get_leader_len(saved_line, &lead_flags,
1605 							dir == BACKWARD, TRUE);
1606     else
1607 	lead_len = 0;
1608     if (lead_len > 0)
1609     {
1610 	char_u	*lead_repl = NULL;	    // replaces comment leader
1611 	int	lead_repl_len = 0;	    // length of *lead_repl
1612 	char_u	lead_middle[COM_MAX_LEN];   // middle-comment string
1613 	char_u	lead_end[COM_MAX_LEN];	    // end-comment string
1614 	char_u	*comment_end = NULL;	    // where lead_end has been found
1615 	int	extra_space = FALSE;	    // append extra space
1616 	int	current_flag;
1617 	int	require_blank = FALSE;	    // requires blank after middle
1618 	char_u	*p2;
1619 
1620 	// If the comment leader has the start, middle or end flag, it may not
1621 	// be used or may be replaced with the middle leader.
1622 	for (p = lead_flags; *p && *p != ':'; ++p)
1623 	{
1624 	    if (*p == COM_BLANK)
1625 	    {
1626 		require_blank = TRUE;
1627 		continue;
1628 	    }
1629 	    if (*p == COM_START || *p == COM_MIDDLE)
1630 	    {
1631 		current_flag = *p;
1632 		if (*p == COM_START)
1633 		{
1634 		    // Doing "O" on a start of comment does not insert leader.
1635 		    if (dir == BACKWARD)
1636 		    {
1637 			lead_len = 0;
1638 			break;
1639 		    }
1640 
1641 		    // find start of middle part
1642 		    (void)copy_option_part(&p, lead_middle, COM_MAX_LEN, ",");
1643 		    require_blank = FALSE;
1644 		}
1645 
1646 		// Isolate the strings of the middle and end leader.
1647 		while (*p && p[-1] != ':')	// find end of middle flags
1648 		{
1649 		    if (*p == COM_BLANK)
1650 			require_blank = TRUE;
1651 		    ++p;
1652 		}
1653 		(void)copy_option_part(&p, lead_middle, COM_MAX_LEN, ",");
1654 
1655 		while (*p && p[-1] != ':')	// find end of end flags
1656 		{
1657 		    // Check whether we allow automatic ending of comments
1658 		    if (*p == COM_AUTO_END)
1659 			end_comment_pending = -1; // means we want to set it
1660 		    ++p;
1661 		}
1662 		n = copy_option_part(&p, lead_end, COM_MAX_LEN, ",");
1663 
1664 		if (end_comment_pending == -1)	// we can set it now
1665 		    end_comment_pending = lead_end[n - 1];
1666 
1667 		// If the end of the comment is in the same line, don't use
1668 		// the comment leader.
1669 		if (dir == FORWARD)
1670 		{
1671 		    for (p = saved_line + lead_len; *p; ++p)
1672 			if (STRNCMP(p, lead_end, n) == 0)
1673 			{
1674 			    comment_end = p;
1675 			    lead_len = 0;
1676 			    break;
1677 			}
1678 		}
1679 
1680 		// Doing "o" on a start of comment inserts the middle leader.
1681 		if (lead_len > 0)
1682 		{
1683 		    if (current_flag == COM_START)
1684 		    {
1685 			lead_repl = lead_middle;
1686 			lead_repl_len = (int)STRLEN(lead_middle);
1687 		    }
1688 
1689 		    // If we have hit RETURN immediately after the start
1690 		    // comment leader, then put a space after the middle
1691 		    // comment leader on the next line.
1692 		    if (!VIM_ISWHITE(saved_line[lead_len - 1])
1693 			    && ((p_extra != NULL
1694 				    && (int)curwin->w_cursor.col == lead_len)
1695 				|| (p_extra == NULL
1696 				    && saved_line[lead_len] == NUL)
1697 				|| require_blank))
1698 			extra_space = TRUE;
1699 		}
1700 		break;
1701 	    }
1702 	    if (*p == COM_END)
1703 	    {
1704 		// Doing "o" on the end of a comment does not insert leader.
1705 		// Remember where the end is, might want to use it to find the
1706 		// start (for C-comments).
1707 		if (dir == FORWARD)
1708 		{
1709 		    comment_end = skipwhite(saved_line);
1710 		    lead_len = 0;
1711 		    break;
1712 		}
1713 
1714 		// Doing "O" on the end of a comment inserts the middle leader.
1715 		// Find the string for the middle leader, searching backwards.
1716 		while (p > curbuf->b_p_com && *p != ',')
1717 		    --p;
1718 		for (lead_repl = p; lead_repl > curbuf->b_p_com
1719 					 && lead_repl[-1] != ':'; --lead_repl)
1720 		    ;
1721 		lead_repl_len = (int)(p - lead_repl);
1722 
1723 		// We can probably always add an extra space when doing "O" on
1724 		// the comment-end
1725 		extra_space = TRUE;
1726 
1727 		// Check whether we allow automatic ending of comments
1728 		for (p2 = p; *p2 && *p2 != ':'; p2++)
1729 		{
1730 		    if (*p2 == COM_AUTO_END)
1731 			end_comment_pending = -1; // means we want to set it
1732 		}
1733 		if (end_comment_pending == -1)
1734 		{
1735 		    // Find last character in end-comment string
1736 		    while (*p2 && *p2 != ',')
1737 			p2++;
1738 		    end_comment_pending = p2[-1];
1739 		}
1740 		break;
1741 	    }
1742 	    if (*p == COM_FIRST)
1743 	    {
1744 		// Comment leader for first line only:	Don't repeat leader
1745 		// when using "O", blank out leader when using "o".
1746 		if (dir == BACKWARD)
1747 		    lead_len = 0;
1748 		else
1749 		{
1750 		    lead_repl = (char_u *)"";
1751 		    lead_repl_len = 0;
1752 		}
1753 		break;
1754 	    }
1755 	}
1756 	if (lead_len)
1757 	{
1758 	    // allocate buffer (may concatenate p_extra later)
1759 	    leader = alloc(lead_len + lead_repl_len + extra_space + extra_len
1760 		     + (second_line_indent > 0 ? second_line_indent : 0) + 1);
1761 	    allocated = leader;		    // remember to free it later
1762 
1763 	    if (leader == NULL)
1764 		lead_len = 0;
1765 	    else
1766 	    {
1767 		vim_strncpy(leader, saved_line, lead_len);
1768 
1769 		// Replace leader with lead_repl, right or left adjusted
1770 		if (lead_repl != NULL)
1771 		{
1772 		    int		c = 0;
1773 		    int		off = 0;
1774 
1775 		    for (p = lead_flags; *p != NUL && *p != ':'; )
1776 		    {
1777 			if (*p == COM_RIGHT || *p == COM_LEFT)
1778 			    c = *p++;
1779 			else if (VIM_ISDIGIT(*p) || *p == '-')
1780 			    off = getdigits(&p);
1781 			else
1782 			    ++p;
1783 		    }
1784 		    if (c == COM_RIGHT)    // right adjusted leader
1785 		    {
1786 			// find last non-white in the leader to line up with
1787 			for (p = leader + lead_len - 1; p > leader
1788 						      && VIM_ISWHITE(*p); --p)
1789 			    ;
1790 			++p;
1791 
1792 			// Compute the length of the replaced characters in
1793 			// screen characters, not bytes.
1794 			{
1795 			    int	    repl_size = vim_strnsize(lead_repl,
1796 							       lead_repl_len);
1797 			    int	    old_size = 0;
1798 			    char_u  *endp = p;
1799 			    int	    l;
1800 
1801 			    while (old_size < repl_size && p > leader)
1802 			    {
1803 				MB_PTR_BACK(leader, p);
1804 				old_size += ptr2cells(p);
1805 			    }
1806 			    l = lead_repl_len - (int)(endp - p);
1807 			    if (l != 0)
1808 				mch_memmove(endp + l, endp,
1809 					(size_t)((leader + lead_len) - endp));
1810 			    lead_len += l;
1811 			}
1812 			mch_memmove(p, lead_repl, (size_t)lead_repl_len);
1813 			if (p + lead_repl_len > leader + lead_len)
1814 			    p[lead_repl_len] = NUL;
1815 
1816 			// blank-out any other chars from the old leader.
1817 			while (--p >= leader)
1818 			{
1819 			    int l = mb_head_off(leader, p);
1820 
1821 			    if (l > 1)
1822 			    {
1823 				p -= l;
1824 				if (ptr2cells(p) > 1)
1825 				{
1826 				    p[1] = ' ';
1827 				    --l;
1828 				}
1829 				mch_memmove(p + 1, p + l + 1,
1830 				   (size_t)((leader + lead_len) - (p + l + 1)));
1831 				lead_len -= l;
1832 				*p = ' ';
1833 			    }
1834 			    else if (!VIM_ISWHITE(*p))
1835 				*p = ' ';
1836 			}
1837 		    }
1838 		    else	// left adjusted leader
1839 		    {
1840 			p = skipwhite(leader);
1841 
1842 			// Compute the length of the replaced characters in
1843 			// screen characters, not bytes. Move the part that is
1844 			// not to be overwritten.
1845 			{
1846 			    int	    repl_size = vim_strnsize(lead_repl,
1847 							       lead_repl_len);
1848 			    int	    i;
1849 			    int	    l;
1850 
1851 			    for (i = 0; i < lead_len && p[i] != NUL; i += l)
1852 			    {
1853 				l = (*mb_ptr2len)(p + i);
1854 				if (vim_strnsize(p, i + l) > repl_size)
1855 				    break;
1856 			    }
1857 			    if (i != lead_repl_len)
1858 			    {
1859 				mch_memmove(p + lead_repl_len, p + i,
1860 				       (size_t)(lead_len - i - (p - leader)));
1861 				lead_len += lead_repl_len - i;
1862 			    }
1863 			}
1864 			mch_memmove(p, lead_repl, (size_t)lead_repl_len);
1865 
1866 			// Replace any remaining non-white chars in the old
1867 			// leader by spaces.  Keep Tabs, the indent must
1868 			// remain the same.
1869 			for (p += lead_repl_len; p < leader + lead_len; ++p)
1870 			    if (!VIM_ISWHITE(*p))
1871 			    {
1872 				// Don't put a space before a TAB.
1873 				if (p + 1 < leader + lead_len && p[1] == TAB)
1874 				{
1875 				    --lead_len;
1876 				    mch_memmove(p, p + 1,
1877 						     (leader + lead_len) - p);
1878 				}
1879 				else
1880 				{
1881 				    int	    l = (*mb_ptr2len)(p);
1882 
1883 				    if (l > 1)
1884 				    {
1885 					if (ptr2cells(p) > 1)
1886 					{
1887 					    // Replace a double-wide char with
1888 					    // two spaces
1889 					    --l;
1890 					    *p++ = ' ';
1891 					}
1892 					mch_memmove(p + 1, p + l,
1893 						     (leader + lead_len) - p);
1894 					lead_len -= l - 1;
1895 				    }
1896 				    *p = ' ';
1897 				}
1898 			    }
1899 			*p = NUL;
1900 		    }
1901 
1902 		    // Recompute the indent, it may have changed.
1903 		    if (curbuf->b_p_ai
1904 #ifdef FEAT_SMARTINDENT
1905 					|| do_si
1906 #endif
1907 							   )
1908 #ifdef FEAT_VARTABS
1909 			newindent = get_indent_str_vtab(leader, curbuf->b_p_ts,
1910 						 curbuf->b_p_vts_array, FALSE);
1911 #else
1912 			newindent = get_indent_str(leader,
1913 						   (int)curbuf->b_p_ts, FALSE);
1914 #endif
1915 
1916 		    // Add the indent offset
1917 		    if (newindent + off < 0)
1918 		    {
1919 			off = -newindent;
1920 			newindent = 0;
1921 		    }
1922 		    else
1923 			newindent += off;
1924 
1925 		    // Correct trailing spaces for the shift, so that
1926 		    // alignment remains equal.
1927 		    while (off > 0 && lead_len > 0
1928 					       && leader[lead_len - 1] == ' ')
1929 		    {
1930 			// Don't do it when there is a tab before the space
1931 			if (vim_strchr(skipwhite(leader), '\t') != NULL)
1932 			    break;
1933 			--lead_len;
1934 			--off;
1935 		    }
1936 
1937 		    // If the leader ends in white space, don't add an
1938 		    // extra space
1939 		    if (lead_len > 0 && VIM_ISWHITE(leader[lead_len - 1]))
1940 			extra_space = FALSE;
1941 		    leader[lead_len] = NUL;
1942 		}
1943 
1944 		if (extra_space)
1945 		{
1946 		    leader[lead_len++] = ' ';
1947 		    leader[lead_len] = NUL;
1948 		}
1949 
1950 		newcol = lead_len;
1951 
1952 		// if a new indent will be set below, remove the indent that
1953 		// is in the comment leader
1954 		if (newindent
1955 #ifdef FEAT_SMARTINDENT
1956 				|| did_si
1957 #endif
1958 					   )
1959 		{
1960 		    while (lead_len && VIM_ISWHITE(*leader))
1961 		    {
1962 			--lead_len;
1963 			--newcol;
1964 			++leader;
1965 		    }
1966 		}
1967 
1968 	    }
1969 #ifdef FEAT_SMARTINDENT
1970 	    did_si = can_si = FALSE;
1971 #endif
1972 	}
1973 	else if (comment_end != NULL)
1974 	{
1975 	    // We have finished a comment, so we don't use the leader.
1976 	    // If this was a C-comment and 'ai' or 'si' is set do a normal
1977 	    // indent to align with the line containing the start of the
1978 	    // comment.
1979 	    if (comment_end[0] == '*' && comment_end[1] == '/' &&
1980 			(curbuf->b_p_ai
1981 #ifdef FEAT_SMARTINDENT
1982 					|| do_si
1983 #endif
1984 							   ))
1985 	    {
1986 		old_cursor = curwin->w_cursor;
1987 		curwin->w_cursor.col = (colnr_T)(comment_end - saved_line);
1988 		if ((pos = findmatch(NULL, NUL)) != NULL)
1989 		{
1990 		    curwin->w_cursor.lnum = pos->lnum;
1991 		    newindent = get_indent();
1992 		}
1993 		curwin->w_cursor = old_cursor;
1994 	    }
1995 	}
1996     }
1997 
1998     // (State == INSERT || State == REPLACE), only when dir == FORWARD
1999     if (p_extra != NULL)
2000     {
2001 	*p_extra = saved_char;		// restore char that NUL replaced
2002 
2003 	// When 'ai' set or "flags" has OPENLINE_DELSPACES, skip to the first
2004 	// non-blank.
2005 	//
2006 	// When in REPLACE mode, put the deleted blanks on the replace stack,
2007 	// preceded by a NUL, so they can be put back when a BS is entered.
2008 	if (REPLACE_NORMAL(State))
2009 	    replace_push(NUL);	    // end of extra blanks
2010 	if (curbuf->b_p_ai || (flags & OPENLINE_DELSPACES))
2011 	{
2012 	    while ((*p_extra == ' ' || *p_extra == '\t')
2013 		    && (!enc_utf8
2014 			       || !utf_iscomposing(utf_ptr2char(p_extra + 1))))
2015 	    {
2016 		if (REPLACE_NORMAL(State))
2017 		    replace_push(*p_extra);
2018 		++p_extra;
2019 		++less_cols_off;
2020 	    }
2021 	}
2022 
2023 	// columns for marks adjusted for removed columns
2024 	less_cols = (int)(p_extra - saved_line);
2025     }
2026 
2027     if (p_extra == NULL)
2028 	p_extra = (char_u *)"";		    // append empty line
2029 
2030     // concatenate leader and p_extra, if there is a leader
2031     if (lead_len)
2032     {
2033 	if (flags & OPENLINE_COM_LIST && second_line_indent > 0)
2034 	{
2035 	    int i;
2036 	    int padding = second_line_indent
2037 					  - (newindent + (int)STRLEN(leader));
2038 
2039 	    // Here whitespace is inserted after the comment char.
2040 	    // Below, set_indent(newindent, SIN_INSERT) will insert the
2041 	    // whitespace needed before the comment char.
2042 	    for (i = 0; i < padding; i++)
2043 	    {
2044 		STRCAT(leader, " ");
2045 		less_cols--;
2046 		newcol++;
2047 	    }
2048 	}
2049 	STRCAT(leader, p_extra);
2050 	p_extra = leader;
2051 	did_ai = TRUE;	    // So truncating blanks works with comments
2052 	less_cols -= lead_len;
2053     }
2054     else
2055 	end_comment_pending = NUL;  // turns out there was no leader
2056 
2057     old_cursor = curwin->w_cursor;
2058     if (dir == BACKWARD)
2059 	--curwin->w_cursor.lnum;
2060     if (!(State & VREPLACE_FLAG) || old_cursor.lnum >= orig_line_count)
2061     {
2062 	if (ml_append(curwin->w_cursor.lnum, p_extra, (colnr_T)0, FALSE)
2063 								      == FAIL)
2064 	    goto theend;
2065 	// Postpone calling changed_lines(), because it would mess up folding
2066 	// with markers.
2067 	// Skip mark_adjust when adding a line after the last one, there can't
2068 	// be marks there. But still needed in diff mode.
2069 	if (curwin->w_cursor.lnum + 1 < curbuf->b_ml.ml_line_count
2070 #ifdef FEAT_DIFF
2071 		|| curwin->w_p_diff
2072 #endif
2073 	    )
2074 	    mark_adjust(curwin->w_cursor.lnum + 1, (linenr_T)MAXLNUM, 1L, 0L);
2075 	did_append = TRUE;
2076 #ifdef FEAT_PROP_POPUP
2077 	if ((State & INSERT) && !(State & VREPLACE_FLAG))
2078 	    // properties after the split move to the next line
2079 	    adjust_props_for_split(curwin->w_cursor.lnum, curwin->w_cursor.lnum,
2080 						  curwin->w_cursor.col + 1, 0);
2081 #endif
2082     }
2083     else
2084     {
2085 	// In VREPLACE mode we are starting to replace the next line.
2086 	curwin->w_cursor.lnum++;
2087 	if (curwin->w_cursor.lnum >= Insstart.lnum + vr_lines_changed)
2088 	{
2089 	    // In case we NL to a new line, BS to the previous one, and NL
2090 	    // again, we don't want to save the new line for undo twice.
2091 	    (void)u_save_cursor();		    // errors are ignored!
2092 	    vr_lines_changed++;
2093 	}
2094 	ml_replace(curwin->w_cursor.lnum, p_extra, TRUE);
2095 	changed_bytes(curwin->w_cursor.lnum, 0);
2096 	curwin->w_cursor.lnum--;
2097 	did_append = FALSE;
2098     }
2099 
2100     if (newindent
2101 #ifdef FEAT_SMARTINDENT
2102 		    || did_si
2103 #endif
2104 				)
2105     {
2106 	++curwin->w_cursor.lnum;
2107 #ifdef FEAT_SMARTINDENT
2108 	if (did_si)
2109 	{
2110 	    int sw = (int)get_sw_value(curbuf);
2111 
2112 	    if (p_sr)
2113 		newindent -= newindent % sw;
2114 	    newindent += sw;
2115 	}
2116 #endif
2117 	// Copy the indent
2118 	if (curbuf->b_p_ci)
2119 	{
2120 	    (void)copy_indent(newindent, saved_line);
2121 
2122 	    // Set the 'preserveindent' option so that any further screwing
2123 	    // with the line doesn't entirely destroy our efforts to preserve
2124 	    // it.  It gets restored at the function end.
2125 	    curbuf->b_p_pi = TRUE;
2126 	}
2127 	else
2128 	    (void)set_indent(newindent, SIN_INSERT);
2129 	less_cols -= curwin->w_cursor.col;
2130 
2131 	ai_col = curwin->w_cursor.col;
2132 
2133 	// In REPLACE mode, for each character in the new indent, there must
2134 	// be a NUL on the replace stack, for when it is deleted with BS
2135 	if (REPLACE_NORMAL(State))
2136 	    for (n = 0; n < (int)curwin->w_cursor.col; ++n)
2137 		replace_push(NUL);
2138 	newcol += curwin->w_cursor.col;
2139 #ifdef FEAT_SMARTINDENT
2140 	if (no_si)
2141 	    did_si = FALSE;
2142 #endif
2143     }
2144 
2145     // In REPLACE mode, for each character in the extra leader, there must be
2146     // a NUL on the replace stack, for when it is deleted with BS.
2147     if (REPLACE_NORMAL(State))
2148 	while (lead_len-- > 0)
2149 	    replace_push(NUL);
2150 
2151     curwin->w_cursor = old_cursor;
2152 
2153     if (dir == FORWARD)
2154     {
2155 	if (trunc_line || (State & INSERT))
2156 	{
2157 	    // truncate current line at cursor
2158 	    saved_line[curwin->w_cursor.col] = NUL;
2159 	    // Remove trailing white space, unless OPENLINE_KEEPTRAIL used.
2160 	    if (trunc_line && !(flags & OPENLINE_KEEPTRAIL))
2161 		truncate_spaces(saved_line);
2162 	    ml_replace(curwin->w_cursor.lnum, saved_line, FALSE);
2163 	    saved_line = NULL;
2164 	    if (did_append)
2165 	    {
2166 		changed_lines(curwin->w_cursor.lnum, curwin->w_cursor.col,
2167 					       curwin->w_cursor.lnum + 1, 1L);
2168 		did_append = FALSE;
2169 
2170 		// Move marks after the line break to the new line.
2171 		if (flags & OPENLINE_MARKFIX)
2172 		    mark_col_adjust(curwin->w_cursor.lnum,
2173 					 curwin->w_cursor.col + less_cols_off,
2174 						      1L, (long)-less_cols, 0);
2175 	    }
2176 	    else
2177 		changed_bytes(curwin->w_cursor.lnum, curwin->w_cursor.col);
2178 	}
2179 
2180 	// Put the cursor on the new line.  Careful: the scrollup() above may
2181 	// have moved w_cursor, we must use old_cursor.
2182 	curwin->w_cursor.lnum = old_cursor.lnum + 1;
2183     }
2184     if (did_append)
2185 	changed_lines(curwin->w_cursor.lnum, 0, curwin->w_cursor.lnum, 1L);
2186 
2187     curwin->w_cursor.col = newcol;
2188     curwin->w_cursor.coladd = 0;
2189 
2190 #if defined(FEAT_LISP) || defined(FEAT_CINDENT)
2191     // In VREPLACE mode, we are handling the replace stack ourselves, so stop
2192     // fixthisline() from doing it (via change_indent()) by telling it we're in
2193     // normal INSERT mode.
2194     if (State & VREPLACE_FLAG)
2195     {
2196 	vreplace_mode = State;	// So we know to put things right later
2197 	State = INSERT;
2198     }
2199     else
2200 	vreplace_mode = 0;
2201 #endif
2202 #ifdef FEAT_LISP
2203     // May do lisp indenting.
2204     if (!p_paste
2205 	    && leader == NULL
2206 	    && curbuf->b_p_lisp
2207 	    && curbuf->b_p_ai)
2208     {
2209 	fixthisline(get_lisp_indent);
2210 	ai_col = (colnr_T)getwhitecols_curline();
2211     }
2212 #endif
2213 #ifdef FEAT_CINDENT
2214     // May do indenting after opening a new line.
2215     if (!p_paste
2216 	    && (curbuf->b_p_cin
2217 #  ifdef FEAT_EVAL
2218 		    || *curbuf->b_p_inde != NUL
2219 #  endif
2220 		)
2221 	    && in_cinkeys(dir == FORWARD
2222 		? KEY_OPEN_FORW
2223 		: KEY_OPEN_BACK, ' ', linewhite(curwin->w_cursor.lnum)))
2224     {
2225 	do_c_expr_indent();
2226 	ai_col = (colnr_T)getwhitecols_curline();
2227     }
2228 #endif
2229 #if defined(FEAT_LISP) || defined(FEAT_CINDENT)
2230     if (vreplace_mode != 0)
2231 	State = vreplace_mode;
2232 #endif
2233 
2234     // Finally, VREPLACE gets the stuff on the new line, then puts back the
2235     // original line, and inserts the new stuff char by char, pushing old stuff
2236     // onto the replace stack (via ins_char()).
2237     if (State & VREPLACE_FLAG)
2238     {
2239 	// Put new line in p_extra
2240 	p_extra = vim_strsave(ml_get_curline());
2241 	if (p_extra == NULL)
2242 	    goto theend;
2243 
2244 	// Put back original line
2245 	ml_replace(curwin->w_cursor.lnum, next_line, FALSE);
2246 
2247 	// Insert new stuff into line again
2248 	curwin->w_cursor.col = 0;
2249 	curwin->w_cursor.coladd = 0;
2250 	ins_bytes(p_extra);	// will call changed_bytes()
2251 	vim_free(p_extra);
2252 	next_line = NULL;
2253     }
2254 
2255     retval = OK;		// success!
2256 theend:
2257     curbuf->b_p_pi = saved_pi;
2258     vim_free(saved_line);
2259     vim_free(next_line);
2260     vim_free(allocated);
2261     return retval;
2262 }
2263 
2264 /*
2265  * Delete from cursor to end of line.
2266  * Caller must have prepared for undo.
2267  * If "fixpos" is TRUE fix the cursor position when done.
2268  *
2269  * Return FAIL for failure, OK otherwise.
2270  */
2271     int
2272 truncate_line(int fixpos)
2273 {
2274     char_u	*newp;
2275     linenr_T	lnum = curwin->w_cursor.lnum;
2276     colnr_T	col = curwin->w_cursor.col;
2277 
2278     if (col == 0)
2279 	newp = vim_strsave((char_u *)"");
2280     else
2281 	newp = vim_strnsave(ml_get(lnum), col);
2282 
2283     if (newp == NULL)
2284 	return FAIL;
2285 
2286     ml_replace(lnum, newp, FALSE);
2287 
2288     // mark the buffer as changed and prepare for displaying
2289     changed_bytes(lnum, curwin->w_cursor.col);
2290 
2291     // If "fixpos" is TRUE we don't want to end up positioned at the NUL.
2292     if (fixpos && curwin->w_cursor.col > 0)
2293 	--curwin->w_cursor.col;
2294 
2295     return OK;
2296 }
2297 
2298 /*
2299  * Delete "nlines" lines at the cursor.
2300  * Saves the lines for undo first if "undo" is TRUE.
2301  */
2302     void
2303 del_lines(long nlines,	int undo)
2304 {
2305     long	n;
2306     linenr_T	first = curwin->w_cursor.lnum;
2307 
2308     if (nlines <= 0)
2309 	return;
2310 
2311     // save the deleted lines for undo
2312     if (undo && u_savedel(first, nlines) == FAIL)
2313 	return;
2314 
2315     for (n = 0; n < nlines; )
2316     {
2317 	if (curbuf->b_ml.ml_flags & ML_EMPTY)	    // nothing to delete
2318 	    break;
2319 
2320 	ml_delete(first, TRUE);
2321 	++n;
2322 
2323 	// If we delete the last line in the file, stop
2324 	if (first > curbuf->b_ml.ml_line_count)
2325 	    break;
2326     }
2327 
2328     // Correct the cursor position before calling deleted_lines_mark(), it may
2329     // trigger a callback to display the cursor.
2330     curwin->w_cursor.col = 0;
2331     check_cursor_lnum();
2332 
2333     // adjust marks, mark the buffer as changed and prepare for displaying
2334     deleted_lines_mark(first, n);
2335 }
2336