xref: /vim-8.2.3635/src/evalbuffer.c (revision 7d60384a)
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  * evalbuffer.c: Buffer related builtin functions
12  */
13 
14 #include "vim.h"
15 
16 #if defined(FEAT_EVAL) || defined(PROTO)
17 /*
18  * Mark references in functions of buffers.
19  */
20     int
21 set_ref_in_buffers(int copyID)
22 {
23     int		abort = FALSE;
24     buf_T	*bp;
25 
26     FOR_ALL_BUFFERS(bp)
27     {
28 	listener_T *lnr;
29 	typval_T tv;
30 
31 	for (lnr = bp->b_listener; !abort && lnr != NULL; lnr = lnr->lr_next)
32 	{
33 	    if (lnr->lr_callback.cb_partial != NULL)
34 	    {
35 		tv.v_type = VAR_PARTIAL;
36 		tv.vval.v_partial = lnr->lr_callback.cb_partial;
37 		abort = abort || set_ref_in_item(&tv, copyID, NULL, NULL);
38 	    }
39 	}
40 # ifdef FEAT_JOB_CHANNEL
41 	if (!abort && bp->b_prompt_callback.cb_partial != NULL)
42 	{
43 	    tv.v_type = VAR_PARTIAL;
44 	    tv.vval.v_partial = bp->b_prompt_callback.cb_partial;
45 	    abort = abort || set_ref_in_item(&tv, copyID, NULL, NULL);
46 	}
47 	if (!abort && bp->b_prompt_interrupt.cb_partial != NULL)
48 	{
49 	    tv.v_type = VAR_PARTIAL;
50 	    tv.vval.v_partial = bp->b_prompt_interrupt.cb_partial;
51 	    abort = abort || set_ref_in_item(&tv, copyID, NULL, NULL);
52 	}
53 # endif
54 	if (abort)
55 	    break;
56     }
57     return abort;
58 }
59 
60     buf_T *
61 buflist_find_by_name(char_u *name, int curtab_only)
62 {
63     int		save_magic;
64     char_u	*save_cpo;
65     buf_T	*buf;
66 
67     // Ignore 'magic' and 'cpoptions' here to make scripts portable
68     save_magic = p_magic;
69     p_magic = TRUE;
70     save_cpo = p_cpo;
71     p_cpo = empty_option;
72 
73     buf = buflist_findnr(buflist_findpat(name, name + STRLEN(name),
74 						    TRUE, FALSE, curtab_only));
75 
76     p_magic = save_magic;
77     p_cpo = save_cpo;
78     return buf;
79 }
80 
81 /*
82  * Find a buffer by number or exact name.
83  */
84     buf_T *
85 find_buffer(typval_T *avar)
86 {
87     buf_T	*buf = NULL;
88 
89     if (avar->v_type == VAR_NUMBER)
90 	buf = buflist_findnr((int)avar->vval.v_number);
91     else if (in_vim9script() && check_for_string_arg(avar, 0) == FAIL)
92 	return NULL;
93     else if (avar->v_type == VAR_STRING && avar->vval.v_string != NULL)
94     {
95 	buf = buflist_findname_exp(avar->vval.v_string);
96 	if (buf == NULL)
97 	{
98 	    // No full path name match, try a match with a URL or a "nofile"
99 	    // buffer, these don't use the full path.
100 	    FOR_ALL_BUFFERS(buf)
101 		if (buf->b_fname != NULL
102 			&& (path_with_url(buf->b_fname)
103 #ifdef FEAT_QUICKFIX
104 			    || bt_nofilename(buf)
105 #endif
106 			   )
107 			&& STRCMP(buf->b_fname, avar->vval.v_string) == 0)
108 		    break;
109 	}
110     }
111     return buf;
112 }
113 
114 /*
115  * If there is a window for "curbuf", make it the current window.
116  */
117     static void
118 find_win_for_curbuf(void)
119 {
120     wininfo_T *wip;
121 
122     FOR_ALL_BUF_WININFO(curbuf, wip)
123     {
124 	if (wip->wi_win != NULL)
125 	{
126 	    curwin = wip->wi_win;
127 	    break;
128 	}
129     }
130 }
131 
132 /*
133  * Set line or list of lines in buffer "buf" to "lines".
134  * Any type is allowed and converted to a string.
135  */
136     static void
137 set_buffer_lines(
138 	buf_T	    *buf,
139 	linenr_T    lnum_arg,
140 	int	    append,
141 	typval_T    *lines,
142 	typval_T    *rettv)
143 {
144     linenr_T    lnum = lnum_arg + (append ? 1 : 0);
145     char_u	*line = NULL;
146     list_T	*l = NULL;
147     listitem_T	*li = NULL;
148     long	added = 0;
149     linenr_T	append_lnum;
150     buf_T	*curbuf_save = NULL;
151     win_T	*curwin_save = NULL;
152     int		is_curbuf = buf == curbuf;
153 
154     // When using the current buffer ml_mfp will be set if needed.  Useful when
155     // setline() is used on startup.  For other buffers the buffer must be
156     // loaded.
157     if (buf == NULL || (!is_curbuf && buf->b_ml.ml_mfp == NULL) || lnum < 1)
158     {
159 	rettv->vval.v_number = 1;	// FAIL
160 	return;
161     }
162 
163     if (!is_curbuf)
164     {
165 	curbuf_save = curbuf;
166 	curwin_save = curwin;
167 	curbuf = buf;
168 	find_win_for_curbuf();
169     }
170 
171     if (append)
172 	// appendbufline() uses the line number below which we insert
173 	append_lnum = lnum - 1;
174     else
175 	// setbufline() uses the line number above which we insert, we only
176 	// append if it's below the last line
177 	append_lnum = curbuf->b_ml.ml_line_count;
178 
179     if (lines->v_type == VAR_LIST)
180     {
181 	l = lines->vval.v_list;
182 	if (l == NULL || list_len(l) == 0)
183 	{
184 	    // set proper return code
185 	    if (lnum > curbuf->b_ml.ml_line_count)
186 		rettv->vval.v_number = 1;	// FAIL
187 	    goto done;
188 	}
189 	CHECK_LIST_MATERIALIZE(l);
190 	li = l->lv_first;
191     }
192     else
193 	line = typval_tostring(lines, FALSE);
194 
195     // default result is zero == OK
196     for (;;)
197     {
198 	if (l != NULL)
199 	{
200 	    // list argument, get next string
201 	    if (li == NULL)
202 		break;
203 	    vim_free(line);
204 	    line = typval_tostring(&li->li_tv, FALSE);
205 	    li = li->li_next;
206 	}
207 
208 	rettv->vval.v_number = 1;	// FAIL
209 	if (line == NULL || lnum > curbuf->b_ml.ml_line_count + 1)
210 	    break;
211 
212 	// When coming here from Insert mode, sync undo, so that this can be
213 	// undone separately from what was previously inserted.
214 	if (u_sync_once == 2)
215 	{
216 	    u_sync_once = 1; // notify that u_sync() was called
217 	    u_sync(TRUE);
218 	}
219 
220 	if (!append && lnum <= curbuf->b_ml.ml_line_count)
221 	{
222 	    // Existing line, replace it.
223 	    // Removes any existing text properties.
224 	    if (u_savesub(lnum) == OK && ml_replace_len(
225 		      lnum, line, (colnr_T)STRLEN(line) + 1, TRUE, TRUE) == OK)
226 	    {
227 		changed_bytes(lnum, 0);
228 		if (is_curbuf && lnum == curwin->w_cursor.lnum)
229 		    check_cursor_col();
230 		rettv->vval.v_number = 0;	// OK
231 	    }
232 	}
233 	else if (added > 0 || u_save(lnum - 1, lnum) == OK)
234 	{
235 	    // append the line
236 	    ++added;
237 	    if (ml_append(lnum - 1, line, (colnr_T)0, FALSE) == OK)
238 		rettv->vval.v_number = 0;	// OK
239 	}
240 
241 	if (l == NULL)			// only one string argument
242 	    break;
243 	++lnum;
244     }
245     vim_free(line);
246 
247     if (added > 0)
248     {
249 	win_T	    *wp;
250 	tabpage_T   *tp;
251 
252 	appended_lines_mark(append_lnum, added);
253 
254 	// Only adjust the cursor for buffers other than the current, unless it
255 	// is the current window.  For curbuf and other windows it has been
256 	// done in mark_adjust_internal().
257 	FOR_ALL_TAB_WINDOWS(tp, wp)
258 	    if (wp->w_buffer == buf
259 		    && (wp->w_buffer != curbuf || wp == curwin)
260 		    && wp->w_cursor.lnum > append_lnum)
261 		wp->w_cursor.lnum += added;
262 	check_cursor_col();
263 	update_topline();
264     }
265 
266 done:
267     if (!is_curbuf)
268     {
269 	curbuf = curbuf_save;
270 	curwin = curwin_save;
271     }
272 }
273 
274 /*
275  * "append(lnum, string/list)" function
276  */
277     void
278 f_append(typval_T *argvars, typval_T *rettv)
279 {
280     linenr_T	lnum = tv_get_lnum(&argvars[0]);
281 
282     set_buffer_lines(curbuf, lnum, TRUE, &argvars[1], rettv);
283 }
284 
285 /*
286  * "appendbufline(buf, lnum, string/list)" function
287  */
288     void
289 f_appendbufline(typval_T *argvars, typval_T *rettv)
290 {
291     linenr_T	lnum;
292     buf_T	*buf;
293 
294     buf = tv_get_buf(&argvars[0], FALSE);
295     if (buf == NULL)
296 	rettv->vval.v_number = 1; // FAIL
297     else
298     {
299 	lnum = tv_get_lnum_buf(&argvars[1], buf);
300 	set_buffer_lines(buf, lnum, TRUE, &argvars[2], rettv);
301     }
302 }
303 
304 /*
305  * "bufadd(expr)" function
306  */
307     void
308 f_bufadd(typval_T *argvars, typval_T *rettv)
309 {
310     char_u *name = tv_get_string(&argvars[0]);
311 
312     rettv->vval.v_number = buflist_add(*name == NUL ? NULL : name, 0);
313 }
314 
315 /*
316  * "bufexists(expr)" function
317  */
318     void
319 f_bufexists(typval_T *argvars, typval_T *rettv)
320 {
321     rettv->vval.v_number = (find_buffer(&argvars[0]) != NULL);
322 }
323 
324 /*
325  * "buflisted(expr)" function
326  */
327     void
328 f_buflisted(typval_T *argvars, typval_T *rettv)
329 {
330     buf_T	*buf;
331 
332     buf = find_buffer(&argvars[0]);
333     rettv->vval.v_number = (buf != NULL && buf->b_p_bl);
334 }
335 
336 /*
337  * "bufload(expr)" function
338  */
339     void
340 f_bufload(typval_T *argvars, typval_T *rettv UNUSED)
341 {
342     buf_T	*buf = get_buf_arg(&argvars[0]);
343 
344     if (buf != NULL)
345 	buffer_ensure_loaded(buf);
346 }
347 
348 /*
349  * "bufloaded(expr)" function
350  */
351     void
352 f_bufloaded(typval_T *argvars, typval_T *rettv)
353 {
354     buf_T	*buf;
355 
356     buf = find_buffer(&argvars[0]);
357     rettv->vval.v_number = (buf != NULL && buf->b_ml.ml_mfp != NULL);
358 }
359 
360 /*
361  * "bufname(expr)" function
362  */
363     void
364 f_bufname(typval_T *argvars, typval_T *rettv)
365 {
366     buf_T	*buf;
367     typval_T	*tv = &argvars[0];
368 
369     if (tv->v_type == VAR_UNKNOWN)
370 	buf = curbuf;
371     else
372 	buf = tv_get_buf_from_arg(tv);
373     rettv->v_type = VAR_STRING;
374     if (buf != NULL && buf->b_fname != NULL)
375 	rettv->vval.v_string = vim_strsave(buf->b_fname);
376     else
377 	rettv->vval.v_string = NULL;
378 }
379 
380 /*
381  * "bufnr(expr)" function
382  */
383     void
384 f_bufnr(typval_T *argvars, typval_T *rettv)
385 {
386     buf_T	*buf;
387     int		error = FALSE;
388     char_u	*name;
389 
390     if (in_vim9script()
391 	    && (check_for_opt_buffer_arg(argvars, 0) == FAIL
392 		|| (argvars[0].v_type != VAR_UNKNOWN
393 		    && check_for_opt_bool_arg(argvars, 1) == FAIL)))
394 	return;
395 
396     if (argvars[0].v_type == VAR_UNKNOWN)
397 	buf = curbuf;
398     else
399 	buf = tv_get_buf_from_arg(&argvars[0]);
400 
401     // If the buffer isn't found and the second argument is not zero create a
402     // new buffer.
403     if (buf == NULL
404 	    && argvars[1].v_type != VAR_UNKNOWN
405 	    && tv_get_bool_chk(&argvars[1], &error) != 0
406 	    && !error
407 	    && (name = tv_get_string_chk(&argvars[0])) != NULL
408 	    && !error)
409 	buf = buflist_new(name, NULL, (linenr_T)1, 0);
410 
411     if (buf != NULL)
412 	rettv->vval.v_number = buf->b_fnum;
413     else
414 	rettv->vval.v_number = -1;
415 }
416 
417     static void
418 buf_win_common(typval_T *argvars, typval_T *rettv, int get_nr)
419 {
420     win_T	*wp;
421     int		winnr = 0;
422     buf_T	*buf;
423 
424     buf = tv_get_buf_from_arg(&argvars[0]);
425     FOR_ALL_WINDOWS(wp)
426     {
427 	++winnr;
428 	if (wp->w_buffer == buf)
429 	    break;
430     }
431     rettv->vval.v_number = (wp != NULL ? (get_nr ? winnr : wp->w_id) : -1);
432 }
433 
434 /*
435  * "bufwinid(nr)" function
436  */
437     void
438 f_bufwinid(typval_T *argvars, typval_T *rettv)
439 {
440     buf_win_common(argvars, rettv, FALSE);
441 }
442 
443 /*
444  * "bufwinnr(nr)" function
445  */
446     void
447 f_bufwinnr(typval_T *argvars, typval_T *rettv)
448 {
449     buf_win_common(argvars, rettv, TRUE);
450 }
451 
452 /*
453  * "deletebufline()" function
454  */
455     void
456 f_deletebufline(typval_T *argvars, typval_T *rettv)
457 {
458     buf_T	*buf;
459     linenr_T	first, last;
460     linenr_T	lnum;
461     long	count;
462     int		is_curbuf;
463     buf_T	*curbuf_save = NULL;
464     win_T	*curwin_save = NULL;
465     tabpage_T	*tp;
466     win_T	*wp;
467 
468     if (in_vim9script()
469 	    && (check_for_buffer_arg(argvars, 0) == FAIL
470 		|| check_for_lnum_arg(argvars, 1) == FAIL
471 		|| check_for_opt_lnum_arg(argvars, 2) == FAIL))
472 	return;
473 
474     buf = tv_get_buf(&argvars[0], FALSE);
475     if (buf == NULL)
476     {
477 	rettv->vval.v_number = 1; // FAIL
478 	return;
479     }
480     is_curbuf = buf == curbuf;
481 
482     first = tv_get_lnum_buf(&argvars[1], buf);
483     if (argvars[2].v_type != VAR_UNKNOWN)
484 	last = tv_get_lnum_buf(&argvars[2], buf);
485     else
486 	last = first;
487 
488     if (buf->b_ml.ml_mfp == NULL || first < 1
489 			   || first > buf->b_ml.ml_line_count || last < first)
490     {
491 	rettv->vval.v_number = 1;	// FAIL
492 	return;
493     }
494 
495     if (!is_curbuf)
496     {
497 	curbuf_save = curbuf;
498 	curwin_save = curwin;
499 	curbuf = buf;
500 	find_win_for_curbuf();
501     }
502     if (last > curbuf->b_ml.ml_line_count)
503 	last = curbuf->b_ml.ml_line_count;
504     count = last - first + 1;
505 
506     // When coming here from Insert mode, sync undo, so that this can be
507     // undone separately from what was previously inserted.
508     if (u_sync_once == 2)
509     {
510 	u_sync_once = 1; // notify that u_sync() was called
511 	u_sync(TRUE);
512     }
513 
514     if (u_save(first - 1, last + 1) == FAIL)
515     {
516 	rettv->vval.v_number = 1;	// FAIL
517     }
518     else
519     {
520 	for (lnum = first; lnum <= last; ++lnum)
521 	    ml_delete_flags(first, ML_DEL_MESSAGE);
522 
523 	FOR_ALL_TAB_WINDOWS(tp, wp)
524 	    if (wp->w_buffer == buf)
525 	    {
526 		if (wp->w_cursor.lnum > last)
527 		    wp->w_cursor.lnum -= count;
528 		else if (wp->w_cursor.lnum> first)
529 		    wp->w_cursor.lnum = first;
530 		if (wp->w_cursor.lnum > wp->w_buffer->b_ml.ml_line_count)
531 		    wp->w_cursor.lnum = wp->w_buffer->b_ml.ml_line_count;
532 	    }
533 	check_cursor_col();
534 	deleted_lines_mark(first, count);
535     }
536 
537     if (!is_curbuf)
538     {
539 	curbuf = curbuf_save;
540 	curwin = curwin_save;
541     }
542 }
543 
544 /*
545  * Returns buffer options, variables and other attributes in a dictionary.
546  */
547     static dict_T *
548 get_buffer_info(buf_T *buf)
549 {
550     dict_T	*dict;
551     tabpage_T	*tp;
552     win_T	*wp;
553     list_T	*windows;
554 
555     dict = dict_alloc();
556     if (dict == NULL)
557 	return NULL;
558 
559     dict_add_number(dict, "bufnr", buf->b_fnum);
560     dict_add_string(dict, "name", buf->b_ffname);
561     dict_add_number(dict, "lnum", buf == curbuf ? curwin->w_cursor.lnum
562 						     : buflist_findlnum(buf));
563     dict_add_number(dict, "linecount", buf->b_ml.ml_line_count);
564     dict_add_number(dict, "loaded", buf->b_ml.ml_mfp != NULL);
565     dict_add_number(dict, "listed", buf->b_p_bl);
566     dict_add_number(dict, "changed", bufIsChanged(buf));
567     dict_add_number(dict, "changedtick", CHANGEDTICK(buf));
568     dict_add_number(dict, "hidden",
569 			    buf->b_ml.ml_mfp != NULL && buf->b_nwindows == 0);
570 
571     // Get a reference to buffer variables
572     dict_add_dict(dict, "variables", buf->b_vars);
573 
574     // List of windows displaying this buffer
575     windows = list_alloc();
576     if (windows != NULL)
577     {
578 	FOR_ALL_TAB_WINDOWS(tp, wp)
579 	    if (wp->w_buffer == buf)
580 		list_append_number(windows, (varnumber_T)wp->w_id);
581 	dict_add_list(dict, "windows", windows);
582     }
583 
584 #ifdef FEAT_PROP_POPUP
585     // List of popup windows displaying this buffer
586     windows = list_alloc();
587     if (windows != NULL)
588     {
589 	FOR_ALL_POPUPWINS(wp)
590 	    if (wp->w_buffer == buf)
591 		list_append_number(windows, (varnumber_T)wp->w_id);
592 	FOR_ALL_TABPAGES(tp)
593 	    FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
594 		if (wp->w_buffer == buf)
595 		    list_append_number(windows, (varnumber_T)wp->w_id);
596 
597 	dict_add_list(dict, "popups", windows);
598     }
599 #endif
600 
601 #ifdef FEAT_SIGNS
602     if (buf->b_signlist != NULL)
603     {
604 	// List of signs placed in this buffer
605 	list_T	*signs = list_alloc();
606 	if (signs != NULL)
607 	{
608 	    get_buffer_signs(buf, signs);
609 	    dict_add_list(dict, "signs", signs);
610 	}
611     }
612 #endif
613 
614 #ifdef FEAT_VIMINFO
615     dict_add_number(dict, "lastused", buf->b_last_used);
616 #endif
617 
618     return dict;
619 }
620 
621 /*
622  * "getbufinfo()" function
623  */
624     void
625 f_getbufinfo(typval_T *argvars, typval_T *rettv)
626 {
627     buf_T	*buf = NULL;
628     buf_T	*argbuf = NULL;
629     dict_T	*d;
630     int		filtered = FALSE;
631     int		sel_buflisted = FALSE;
632     int		sel_bufloaded = FALSE;
633     int		sel_bufmodified = FALSE;
634 
635     if (rettv_list_alloc(rettv) != OK)
636 	return;
637 
638     if (in_vim9script()
639 	    && argvars[0].v_type != VAR_UNKNOWN
640 	    && check_for_buffer_or_dict_arg(argvars, 0) == FAIL)
641 	return;
642 
643     // List of all the buffers or selected buffers
644     if (argvars[0].v_type == VAR_DICT)
645     {
646 	dict_T	*sel_d = argvars[0].vval.v_dict;
647 
648 	if (sel_d != NULL)
649 	{
650 	    filtered = TRUE;
651 	    sel_buflisted = dict_get_bool(sel_d, (char_u *)"buflisted", FALSE);
652 	    sel_bufloaded = dict_get_bool(sel_d, (char_u *)"bufloaded", FALSE);
653 	    sel_bufmodified = dict_get_bool(sel_d, (char_u *)"bufmodified",
654 									FALSE);
655 	}
656     }
657     else if (argvars[0].v_type != VAR_UNKNOWN)
658     {
659 	// Information about one buffer.  Argument specifies the buffer
660 	argbuf = tv_get_buf_from_arg(&argvars[0]);
661 	if (argbuf == NULL)
662 	    return;
663     }
664 
665     // Return information about all the buffers or a specified buffer
666     FOR_ALL_BUFFERS(buf)
667     {
668 	if (argbuf != NULL && argbuf != buf)
669 	    continue;
670 	if (filtered && ((sel_bufloaded && buf->b_ml.ml_mfp == NULL)
671 			|| (sel_buflisted && !buf->b_p_bl)
672 			|| (sel_bufmodified && !buf->b_changed)))
673 	    continue;
674 
675 	d = get_buffer_info(buf);
676 	if (d != NULL)
677 	    list_append_dict(rettv->vval.v_list, d);
678 	if (argbuf != NULL)
679 	    return;
680     }
681 }
682 
683 /*
684  * Get line or list of lines from buffer "buf" into "rettv".
685  * Return a range (from start to end) of lines in rettv from the specified
686  * buffer.
687  * If 'retlist' is TRUE, then the lines are returned as a Vim List.
688  */
689     static void
690 get_buffer_lines(
691     buf_T	*buf,
692     linenr_T	start,
693     linenr_T	end,
694     int		retlist,
695     typval_T	*rettv)
696 {
697     char_u	*p;
698 
699     if (retlist)
700     {
701 	if (rettv_list_alloc(rettv) == FAIL)
702 	    return;
703     }
704     else
705     {
706 	rettv->v_type = VAR_STRING;
707 	rettv->vval.v_string = NULL;
708     }
709 
710     if (buf == NULL || buf->b_ml.ml_mfp == NULL || start < 0)
711 	return;
712 
713     if (!retlist)
714     {
715 	if (start >= 1 && start <= buf->b_ml.ml_line_count)
716 	    p = ml_get_buf(buf, start, FALSE);
717 	else
718 	    p = (char_u *)"";
719 	rettv->vval.v_string = vim_strsave(p);
720     }
721     else
722     {
723 	if (end < start)
724 	    return;
725 
726 	if (start < 1)
727 	    start = 1;
728 	if (end > buf->b_ml.ml_line_count)
729 	    end = buf->b_ml.ml_line_count;
730 	while (start <= end)
731 	    if (list_append_string(rettv->vval.v_list,
732 				 ml_get_buf(buf, start++, FALSE), -1) == FAIL)
733 		break;
734     }
735 }
736 
737 /*
738  * "getbufline()" function
739  */
740     void
741 f_getbufline(typval_T *argvars, typval_T *rettv)
742 {
743     linenr_T	lnum = 1;
744     linenr_T	end = 1;
745     buf_T	*buf;
746 
747     if (in_vim9script()
748 	    && (check_for_buffer_arg(argvars, 0) == FAIL
749 		|| check_for_lnum_arg(argvars, 1) == FAIL
750 		|| check_for_opt_lnum_arg(argvars, 2) == FAIL))
751 	return;
752 
753     buf = tv_get_buf_from_arg(&argvars[0]);
754     if (buf != NULL)
755     {
756 	lnum = tv_get_lnum_buf(&argvars[1], buf);
757 	if (argvars[2].v_type == VAR_UNKNOWN)
758 	    end = lnum;
759 	else
760 	    end = tv_get_lnum_buf(&argvars[2], buf);
761     }
762 
763     get_buffer_lines(buf, lnum, end, TRUE, rettv);
764 }
765 
766     type_T *
767 ret_f_getline(int argcount, type_T **argtypes UNUSED)
768 {
769     return argcount == 1 ? &t_string : &t_list_string;
770 }
771 
772 /*
773  * "getline(lnum, [end])" function
774  */
775     void
776 f_getline(typval_T *argvars, typval_T *rettv)
777 {
778     linenr_T	lnum;
779     linenr_T	end;
780     int		retlist;
781 
782     if (in_vim9script()
783 	    && (check_for_lnum_arg(argvars, 0) == FAIL
784 		|| check_for_opt_lnum_arg(argvars, 1) == FAIL))
785 	return;
786 
787     lnum = tv_get_lnum(argvars);
788     if (argvars[1].v_type == VAR_UNKNOWN)
789     {
790 	end = 0;
791 	retlist = FALSE;
792     }
793     else
794     {
795 	end = tv_get_lnum(&argvars[1]);
796 	retlist = TRUE;
797     }
798 
799     get_buffer_lines(curbuf, lnum, end, retlist, rettv);
800 }
801 
802 /*
803  * "setbufline()" function
804  */
805     void
806 f_setbufline(typval_T *argvars, typval_T *rettv)
807 {
808     linenr_T	lnum;
809     buf_T	*buf;
810 
811     buf = tv_get_buf(&argvars[0], FALSE);
812     if (buf == NULL)
813 	rettv->vval.v_number = 1; // FAIL
814     else
815     {
816 	lnum = tv_get_lnum_buf(&argvars[1], buf);
817 	set_buffer_lines(buf, lnum, FALSE, &argvars[2], rettv);
818     }
819 }
820 
821 /*
822  * "setline()" function
823  */
824     void
825 f_setline(typval_T *argvars, typval_T *rettv)
826 {
827     linenr_T	lnum = tv_get_lnum(&argvars[0]);
828 
829     set_buffer_lines(curbuf, lnum, FALSE, &argvars[1], rettv);
830 }
831 #endif  // FEAT_EVAL
832 
833 #if defined(FEAT_JOB_CHANNEL) \
834 	|| defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) \
835 	|| defined(PROTO)
836 /*
837  * Make "buf" the current buffer.  restore_buffer() MUST be called to undo.
838  * No autocommands will be executed.  Use aucmd_prepbuf() if there are any.
839  */
840     void
841 switch_buffer(bufref_T *save_curbuf, buf_T *buf)
842 {
843     block_autocmds();
844 #ifdef FEAT_FOLDING
845     ++disable_fold_update;
846 #endif
847     set_bufref(save_curbuf, curbuf);
848     --curbuf->b_nwindows;
849     curbuf = buf;
850     curwin->w_buffer = buf;
851     ++curbuf->b_nwindows;
852 }
853 
854 /*
855  * Restore the current buffer after using switch_buffer().
856  */
857     void
858 restore_buffer(bufref_T *save_curbuf)
859 {
860     unblock_autocmds();
861 #ifdef FEAT_FOLDING
862     --disable_fold_update;
863 #endif
864     // Check for valid buffer, just in case.
865     if (bufref_valid(save_curbuf))
866     {
867 	--curbuf->b_nwindows;
868 	curwin->w_buffer = save_curbuf->br_buf;
869 	curbuf = save_curbuf->br_buf;
870 	++curbuf->b_nwindows;
871     }
872 }
873 
874 /*
875  * Find a window for buffer "buf".
876  * If found OK is returned and "wp" and "tp" are set to the window and tabpage.
877  * If not found FAIL is returned.
878  */
879     static int
880 find_win_for_buf(
881     buf_T     *buf,
882     win_T     **wp,
883     tabpage_T **tp)
884 {
885     FOR_ALL_TAB_WINDOWS(*tp, *wp)
886 	if ((*wp)->w_buffer == buf)
887 	    return OK;
888     return FAIL;
889 }
890 
891 /*
892  * Find a window that contains "buf" and switch to it.
893  * If there is no such window, use the current window and change "curbuf".
894  * Caller must initialize save_curbuf to NULL.
895  * restore_win_for_buf() MUST be called later!
896  */
897     void
898 switch_to_win_for_buf(
899     buf_T	*buf,
900     win_T	**save_curwinp,
901     tabpage_T	**save_curtabp,
902     bufref_T	*save_curbuf)
903 {
904     win_T	*wp;
905     tabpage_T	*tp;
906 
907     if (find_win_for_buf(buf, &wp, &tp) == FAIL)
908 	switch_buffer(save_curbuf, buf);
909     else if (switch_win(save_curwinp, save_curtabp, wp, tp, TRUE) == FAIL)
910     {
911 	restore_win(*save_curwinp, *save_curtabp, TRUE);
912 	switch_buffer(save_curbuf, buf);
913     }
914 }
915 
916     void
917 restore_win_for_buf(
918     win_T	*save_curwin,
919     tabpage_T	*save_curtab,
920     bufref_T	*save_curbuf)
921 {
922     if (save_curbuf->br_buf == NULL)
923 	restore_win(save_curwin, save_curtab, TRUE);
924     else
925 	restore_buffer(save_curbuf);
926 }
927 #endif
928