xref: /vim-8.2.3635/src/evalbuffer.c (revision a0122dcd)
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 (avar->v_type == VAR_STRING && avar->vval.v_string != NULL)
92     {
93 	buf = buflist_findname_exp(avar->vval.v_string);
94 	if (buf == NULL)
95 	{
96 	    // No full path name match, try a match with a URL or a "nofile"
97 	    // buffer, these don't use the full path.
98 	    FOR_ALL_BUFFERS(buf)
99 		if (buf->b_fname != NULL
100 			&& (path_with_url(buf->b_fname)
101 #ifdef FEAT_QUICKFIX
102 			    || bt_nofilename(buf)
103 #endif
104 			   )
105 			&& STRCMP(buf->b_fname, avar->vval.v_string) == 0)
106 		    break;
107 	}
108     }
109     return buf;
110 }
111 
112 /*
113  * If there is a window for "curbuf", make it the current window.
114  */
115     static void
116 find_win_for_curbuf(void)
117 {
118     wininfo_T *wip;
119 
120     FOR_ALL_BUF_WININFO(curbuf, wip)
121     {
122 	if (wip->wi_win != NULL)
123 	{
124 	    curwin = wip->wi_win;
125 	    break;
126 	}
127     }
128 }
129 
130 /*
131  * Set line or list of lines in buffer "buf".
132  */
133     static void
134 set_buffer_lines(
135 	buf_T	    *buf,
136 	linenr_T    lnum_arg,
137 	int	    append,
138 	typval_T    *lines,
139 	typval_T    *rettv)
140 {
141     linenr_T    lnum = lnum_arg + (append ? 1 : 0);
142     char_u	*line = NULL;
143     list_T	*l = NULL;
144     listitem_T	*li = NULL;
145     long	added = 0;
146     linenr_T	append_lnum;
147     buf_T	*curbuf_save = NULL;
148     win_T	*curwin_save = NULL;
149     int		is_curbuf = buf == curbuf;
150 
151     // When using the current buffer ml_mfp will be set if needed.  Useful when
152     // setline() is used on startup.  For other buffers the buffer must be
153     // loaded.
154     if (buf == NULL || (!is_curbuf && buf->b_ml.ml_mfp == NULL) || lnum < 1)
155     {
156 	rettv->vval.v_number = 1;	// FAIL
157 	return;
158     }
159 
160     if (!is_curbuf)
161     {
162 	curbuf_save = curbuf;
163 	curwin_save = curwin;
164 	curbuf = buf;
165 	find_win_for_curbuf();
166     }
167 
168     if (append)
169 	// appendbufline() uses the line number below which we insert
170 	append_lnum = lnum - 1;
171     else
172 	// setbufline() uses the line number above which we insert, we only
173 	// append if it's below the last line
174 	append_lnum = curbuf->b_ml.ml_line_count;
175 
176     if (lines->v_type == VAR_LIST)
177     {
178 	l = lines->vval.v_list;
179 	if (l == NULL || list_len(l) == 0)
180 	{
181 	    // set proper return code
182 	    if (lnum > curbuf->b_ml.ml_line_count)
183 		rettv->vval.v_number = 1;	// FAIL
184 	    goto done;
185 	}
186 	CHECK_LIST_MATERIALIZE(l);
187 	li = l->lv_first;
188     }
189     else
190 	line = tv_get_string_chk(lines);
191 
192     // default result is zero == OK
193     for (;;)
194     {
195 	if (l != NULL)
196 	{
197 	    // list argument, get next string
198 	    if (li == NULL)
199 		break;
200 	    line = tv_get_string_chk(&li->li_tv);
201 	    li = li->li_next;
202 	}
203 
204 	rettv->vval.v_number = 1;	// FAIL
205 	if (line == NULL || lnum > curbuf->b_ml.ml_line_count + 1)
206 	    break;
207 
208 	// When coming here from Insert mode, sync undo, so that this can be
209 	// undone separately from what was previously inserted.
210 	if (u_sync_once == 2)
211 	{
212 	    u_sync_once = 1; // notify that u_sync() was called
213 	    u_sync(TRUE);
214 	}
215 
216 	if (!append && lnum <= curbuf->b_ml.ml_line_count)
217 	{
218 	    // Existing line, replace it.
219 	    // Removes any existing text properties.
220 	    if (u_savesub(lnum) == OK && ml_replace_len(
221 		      lnum, line, (colnr_T)STRLEN(line) + 1, TRUE, TRUE) == OK)
222 	    {
223 		changed_bytes(lnum, 0);
224 		if (is_curbuf && lnum == curwin->w_cursor.lnum)
225 		    check_cursor_col();
226 		rettv->vval.v_number = 0;	// OK
227 	    }
228 	}
229 	else if (added > 0 || u_save(lnum - 1, lnum) == OK)
230 	{
231 	    // append the line
232 	    ++added;
233 	    if (ml_append(lnum - 1, line, (colnr_T)0, FALSE) == OK)
234 		rettv->vval.v_number = 0;	// OK
235 	}
236 
237 	if (l == NULL)			// only one string argument
238 	    break;
239 	++lnum;
240     }
241 
242     if (added > 0)
243     {
244 	win_T	    *wp;
245 	tabpage_T   *tp;
246 
247 	appended_lines_mark(append_lnum, added);
248 
249 	// Only adjust the cursor for buffers other than the current, unless it
250 	// is the current window.  For curbuf and other windows it has been
251 	// done in mark_adjust_internal().
252 	FOR_ALL_TAB_WINDOWS(tp, wp)
253 	    if (wp->w_buffer == buf
254 		    && (wp->w_buffer != curbuf || wp == curwin)
255 		    && wp->w_cursor.lnum > append_lnum)
256 		wp->w_cursor.lnum += added;
257 	check_cursor_col();
258 	update_topline();
259     }
260 
261 done:
262     if (!is_curbuf)
263     {
264 	curbuf = curbuf_save;
265 	curwin = curwin_save;
266     }
267 }
268 
269 /*
270  * "append(lnum, string/list)" function
271  */
272     void
273 f_append(typval_T *argvars, typval_T *rettv)
274 {
275     linenr_T	lnum = tv_get_lnum(&argvars[0]);
276 
277     set_buffer_lines(curbuf, lnum, TRUE, &argvars[1], rettv);
278 }
279 
280 /*
281  * "appendbufline(buf, lnum, string/list)" function
282  */
283     void
284 f_appendbufline(typval_T *argvars, typval_T *rettv)
285 {
286     linenr_T	lnum;
287     buf_T	*buf;
288 
289     buf = tv_get_buf(&argvars[0], FALSE);
290     if (buf == NULL)
291 	rettv->vval.v_number = 1; // FAIL
292     else
293     {
294 	lnum = tv_get_lnum_buf(&argvars[1], buf);
295 	set_buffer_lines(buf, lnum, TRUE, &argvars[2], rettv);
296     }
297 }
298 
299 /*
300  * "bufadd(expr)" function
301  */
302     void
303 f_bufadd(typval_T *argvars, typval_T *rettv)
304 {
305     char_u *name = tv_get_string(&argvars[0]);
306 
307     rettv->vval.v_number = buflist_add(*name == NUL ? NULL : name, 0);
308 }
309 
310 /*
311  * "bufexists(expr)" function
312  */
313     void
314 f_bufexists(typval_T *argvars, typval_T *rettv)
315 {
316     rettv->vval.v_number = (find_buffer(&argvars[0]) != NULL);
317 }
318 
319 /*
320  * "buflisted(expr)" function
321  */
322     void
323 f_buflisted(typval_T *argvars, typval_T *rettv)
324 {
325     buf_T	*buf;
326 
327     buf = find_buffer(&argvars[0]);
328     rettv->vval.v_number = (buf != NULL && buf->b_p_bl);
329 }
330 
331 /*
332  * "bufload(expr)" function
333  */
334     void
335 f_bufload(typval_T *argvars, typval_T *rettv UNUSED)
336 {
337     buf_T	*buf = get_buf_arg(&argvars[0]);
338 
339     if (buf != NULL)
340 	buffer_ensure_loaded(buf);
341 }
342 
343 /*
344  * "bufloaded(expr)" function
345  */
346     void
347 f_bufloaded(typval_T *argvars, typval_T *rettv)
348 {
349     buf_T	*buf;
350 
351     buf = find_buffer(&argvars[0]);
352     rettv->vval.v_number = (buf != NULL && buf->b_ml.ml_mfp != NULL);
353 }
354 
355 /*
356  * "bufname(expr)" function
357  */
358     void
359 f_bufname(typval_T *argvars, typval_T *rettv)
360 {
361     buf_T	*buf;
362     typval_T	*tv = &argvars[0];
363 
364     if (tv->v_type == VAR_UNKNOWN)
365 	buf = curbuf;
366     else
367 	buf = tv_get_buf_from_arg(tv);
368     rettv->v_type = VAR_STRING;
369     if (buf != NULL && buf->b_fname != NULL)
370 	rettv->vval.v_string = vim_strsave(buf->b_fname);
371     else
372 	rettv->vval.v_string = NULL;
373 }
374 
375 /*
376  * "bufnr(expr)" function
377  */
378     void
379 f_bufnr(typval_T *argvars, typval_T *rettv)
380 {
381     buf_T	*buf;
382     int		error = FALSE;
383     char_u	*name;
384 
385     if (argvars[0].v_type == VAR_UNKNOWN)
386 	buf = curbuf;
387     else
388 	buf = tv_get_buf_from_arg(&argvars[0]);
389 
390     // If the buffer isn't found and the second argument is not zero create a
391     // new buffer.
392     if (buf == NULL
393 	    && argvars[1].v_type != VAR_UNKNOWN
394 	    && tv_get_bool_chk(&argvars[1], &error) != 0
395 	    && !error
396 	    && (name = tv_get_string_chk(&argvars[0])) != NULL
397 	    && !error)
398 	buf = buflist_new(name, NULL, (linenr_T)1, 0);
399 
400     if (buf != NULL)
401 	rettv->vval.v_number = buf->b_fnum;
402     else
403 	rettv->vval.v_number = -1;
404 }
405 
406     static void
407 buf_win_common(typval_T *argvars, typval_T *rettv, int get_nr)
408 {
409     win_T	*wp;
410     int		winnr = 0;
411     buf_T	*buf;
412 
413     buf = tv_get_buf_from_arg(&argvars[0]);
414     FOR_ALL_WINDOWS(wp)
415     {
416 	++winnr;
417 	if (wp->w_buffer == buf)
418 	    break;
419     }
420     rettv->vval.v_number = (wp != NULL ? (get_nr ? winnr : wp->w_id) : -1);
421 }
422 
423 /*
424  * "bufwinid(nr)" function
425  */
426     void
427 f_bufwinid(typval_T *argvars, typval_T *rettv)
428 {
429     buf_win_common(argvars, rettv, FALSE);
430 }
431 
432 /*
433  * "bufwinnr(nr)" function
434  */
435     void
436 f_bufwinnr(typval_T *argvars, typval_T *rettv)
437 {
438     buf_win_common(argvars, rettv, TRUE);
439 }
440 
441 /*
442  * "deletebufline()" function
443  */
444     void
445 f_deletebufline(typval_T *argvars, typval_T *rettv)
446 {
447     buf_T	*buf;
448     linenr_T	first, last;
449     linenr_T	lnum;
450     long	count;
451     int		is_curbuf;
452     buf_T	*curbuf_save = NULL;
453     win_T	*curwin_save = NULL;
454     tabpage_T	*tp;
455     win_T	*wp;
456 
457     buf = tv_get_buf(&argvars[0], FALSE);
458     if (buf == NULL)
459     {
460 	rettv->vval.v_number = 1; // FAIL
461 	return;
462     }
463     is_curbuf = buf == curbuf;
464 
465     first = tv_get_lnum_buf(&argvars[1], buf);
466     if (argvars[2].v_type != VAR_UNKNOWN)
467 	last = tv_get_lnum_buf(&argvars[2], buf);
468     else
469 	last = first;
470 
471     if (buf->b_ml.ml_mfp == NULL || first < 1
472 			   || first > buf->b_ml.ml_line_count || last < first)
473     {
474 	rettv->vval.v_number = 1;	// FAIL
475 	return;
476     }
477 
478     if (!is_curbuf)
479     {
480 	curbuf_save = curbuf;
481 	curwin_save = curwin;
482 	curbuf = buf;
483 	find_win_for_curbuf();
484     }
485     if (last > curbuf->b_ml.ml_line_count)
486 	last = curbuf->b_ml.ml_line_count;
487     count = last - first + 1;
488 
489     // When coming here from Insert mode, sync undo, so that this can be
490     // undone separately from what was previously inserted.
491     if (u_sync_once == 2)
492     {
493 	u_sync_once = 1; // notify that u_sync() was called
494 	u_sync(TRUE);
495     }
496 
497     if (u_save(first - 1, last + 1) == FAIL)
498     {
499 	rettv->vval.v_number = 1;	// FAIL
500 	return;
501     }
502 
503     for (lnum = first; lnum <= last; ++lnum)
504 	ml_delete_flags(first, ML_DEL_MESSAGE);
505 
506     FOR_ALL_TAB_WINDOWS(tp, wp)
507 	if (wp->w_buffer == buf)
508 	{
509 	    if (wp->w_cursor.lnum > last)
510 		wp->w_cursor.lnum -= count;
511 	    else if (wp->w_cursor.lnum> first)
512 		wp->w_cursor.lnum = first;
513 	    if (wp->w_cursor.lnum > wp->w_buffer->b_ml.ml_line_count)
514 		wp->w_cursor.lnum = wp->w_buffer->b_ml.ml_line_count;
515 	}
516     check_cursor_col();
517     deleted_lines_mark(first, count);
518 
519     if (!is_curbuf)
520     {
521 	curbuf = curbuf_save;
522 	curwin = curwin_save;
523     }
524 }
525 
526 /*
527  * Returns buffer options, variables and other attributes in a dictionary.
528  */
529     static dict_T *
530 get_buffer_info(buf_T *buf)
531 {
532     dict_T	*dict;
533     tabpage_T	*tp;
534     win_T	*wp;
535     list_T	*windows;
536 
537     dict = dict_alloc();
538     if (dict == NULL)
539 	return NULL;
540 
541     dict_add_number(dict, "bufnr", buf->b_fnum);
542     dict_add_string(dict, "name", buf->b_ffname);
543     dict_add_number(dict, "lnum", buf == curbuf ? curwin->w_cursor.lnum
544 						     : buflist_findlnum(buf));
545     dict_add_number(dict, "linecount", buf->b_ml.ml_line_count);
546     dict_add_number(dict, "loaded", buf->b_ml.ml_mfp != NULL);
547     dict_add_number(dict, "listed", buf->b_p_bl);
548     dict_add_number(dict, "changed", bufIsChanged(buf));
549     dict_add_number(dict, "changedtick", CHANGEDTICK(buf));
550     dict_add_number(dict, "hidden",
551 			    buf->b_ml.ml_mfp != NULL && buf->b_nwindows == 0);
552 
553     // Get a reference to buffer variables
554     dict_add_dict(dict, "variables", buf->b_vars);
555 
556     // List of windows displaying this buffer
557     windows = list_alloc();
558     if (windows != NULL)
559     {
560 	FOR_ALL_TAB_WINDOWS(tp, wp)
561 	    if (wp->w_buffer == buf)
562 		list_append_number(windows, (varnumber_T)wp->w_id);
563 	dict_add_list(dict, "windows", windows);
564     }
565 
566 #ifdef FEAT_PROP_POPUP
567     // List of popup windows displaying this buffer
568     windows = list_alloc();
569     if (windows != NULL)
570     {
571 	FOR_ALL_POPUPWINS(wp)
572 	    if (wp->w_buffer == buf)
573 		list_append_number(windows, (varnumber_T)wp->w_id);
574 	FOR_ALL_TABPAGES(tp)
575 	    FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
576 		if (wp->w_buffer == buf)
577 		    list_append_number(windows, (varnumber_T)wp->w_id);
578 
579 	dict_add_list(dict, "popups", windows);
580     }
581 #endif
582 
583 #ifdef FEAT_SIGNS
584     if (buf->b_signlist != NULL)
585     {
586 	// List of signs placed in this buffer
587 	list_T	*signs = list_alloc();
588 	if (signs != NULL)
589 	{
590 	    get_buffer_signs(buf, signs);
591 	    dict_add_list(dict, "signs", signs);
592 	}
593     }
594 #endif
595 
596 #ifdef FEAT_VIMINFO
597     dict_add_number(dict, "lastused", buf->b_last_used);
598 #endif
599 
600     return dict;
601 }
602 
603 /*
604  * "getbufinfo()" function
605  */
606     void
607 f_getbufinfo(typval_T *argvars, typval_T *rettv)
608 {
609     buf_T	*buf = NULL;
610     buf_T	*argbuf = NULL;
611     dict_T	*d;
612     int		filtered = FALSE;
613     int		sel_buflisted = FALSE;
614     int		sel_bufloaded = FALSE;
615     int		sel_bufmodified = FALSE;
616 
617     if (rettv_list_alloc(rettv) != OK)
618 	return;
619 
620     // List of all the buffers or selected buffers
621     if (argvars[0].v_type == VAR_DICT)
622     {
623 	dict_T	*sel_d = argvars[0].vval.v_dict;
624 
625 	if (sel_d != NULL)
626 	{
627 	    filtered = TRUE;
628 	    sel_buflisted = dict_get_bool(sel_d, (char_u *)"buflisted", FALSE);
629 	    sel_bufloaded = dict_get_bool(sel_d, (char_u *)"bufloaded", FALSE);
630 	    sel_bufmodified = dict_get_bool(sel_d, (char_u *)"bufmodified",
631 									FALSE);
632 	}
633     }
634     else if (argvars[0].v_type != VAR_UNKNOWN)
635     {
636 	// Information about one buffer.  Argument specifies the buffer
637 	argbuf = tv_get_buf_from_arg(&argvars[0]);
638 	if (argbuf == NULL)
639 	    return;
640     }
641 
642     // Return information about all the buffers or a specified buffer
643     FOR_ALL_BUFFERS(buf)
644     {
645 	if (argbuf != NULL && argbuf != buf)
646 	    continue;
647 	if (filtered && ((sel_bufloaded && buf->b_ml.ml_mfp == NULL)
648 			|| (sel_buflisted && !buf->b_p_bl)
649 			|| (sel_bufmodified && !buf->b_changed)))
650 	    continue;
651 
652 	d = get_buffer_info(buf);
653 	if (d != NULL)
654 	    list_append_dict(rettv->vval.v_list, d);
655 	if (argbuf != NULL)
656 	    return;
657     }
658 }
659 
660 /*
661  * Get line or list of lines from buffer "buf" into "rettv".
662  * Return a range (from start to end) of lines in rettv from the specified
663  * buffer.
664  * If 'retlist' is TRUE, then the lines are returned as a Vim List.
665  */
666     static void
667 get_buffer_lines(
668     buf_T	*buf,
669     linenr_T	start,
670     linenr_T	end,
671     int		retlist,
672     typval_T	*rettv)
673 {
674     char_u	*p;
675 
676     if (retlist)
677     {
678 	if (rettv_list_alloc(rettv) == FAIL)
679 	    return;
680     }
681     else
682     {
683 	rettv->v_type = VAR_STRING;
684 	rettv->vval.v_string = NULL;
685     }
686 
687     if (buf == NULL || buf->b_ml.ml_mfp == NULL || start < 0)
688 	return;
689 
690     if (!retlist)
691     {
692 	if (start >= 1 && start <= buf->b_ml.ml_line_count)
693 	    p = ml_get_buf(buf, start, FALSE);
694 	else
695 	    p = (char_u *)"";
696 	rettv->vval.v_string = vim_strsave(p);
697     }
698     else
699     {
700 	if (end < start)
701 	    return;
702 
703 	if (start < 1)
704 	    start = 1;
705 	if (end > buf->b_ml.ml_line_count)
706 	    end = buf->b_ml.ml_line_count;
707 	while (start <= end)
708 	    if (list_append_string(rettv->vval.v_list,
709 				 ml_get_buf(buf, start++, FALSE), -1) == FAIL)
710 		break;
711     }
712 }
713 
714 /*
715  * "getbufline()" function
716  */
717     void
718 f_getbufline(typval_T *argvars, typval_T *rettv)
719 {
720     linenr_T	lnum = 1;
721     linenr_T	end = 1;
722     buf_T	*buf;
723 
724     buf = tv_get_buf_from_arg(&argvars[0]);
725     if (buf != NULL)
726     {
727 	lnum = tv_get_lnum_buf(&argvars[1], buf);
728 	if (argvars[2].v_type == VAR_UNKNOWN)
729 	    end = lnum;
730 	else
731 	    end = tv_get_lnum_buf(&argvars[2], buf);
732     }
733 
734     get_buffer_lines(buf, lnum, end, TRUE, rettv);
735 }
736 
737     type_T *
738 ret_f_getline(int argcount, type_T **argtypes UNUSED)
739 {
740     return argcount == 1 ? &t_string : &t_list_string;
741 }
742 
743 /*
744  * "getline(lnum, [end])" function
745  */
746     void
747 f_getline(typval_T *argvars, typval_T *rettv)
748 {
749     linenr_T	lnum;
750     linenr_T	end;
751     int		retlist;
752 
753     lnum = tv_get_lnum(argvars);
754     if (argvars[1].v_type == VAR_UNKNOWN)
755     {
756 	end = 0;
757 	retlist = FALSE;
758     }
759     else
760     {
761 	end = tv_get_lnum(&argvars[1]);
762 	retlist = TRUE;
763     }
764 
765     get_buffer_lines(curbuf, lnum, end, retlist, rettv);
766 }
767 
768 /*
769  * "setbufline()" function
770  */
771     void
772 f_setbufline(typval_T *argvars, typval_T *rettv)
773 {
774     linenr_T	lnum;
775     buf_T	*buf;
776 
777     buf = tv_get_buf(&argvars[0], FALSE);
778     if (buf == NULL)
779 	rettv->vval.v_number = 1; // FAIL
780     else
781     {
782 	lnum = tv_get_lnum_buf(&argvars[1], buf);
783 	set_buffer_lines(buf, lnum, FALSE, &argvars[2], rettv);
784     }
785 }
786 
787 /*
788  * "setline()" function
789  */
790     void
791 f_setline(typval_T *argvars, typval_T *rettv)
792 {
793     linenr_T	lnum = tv_get_lnum(&argvars[0]);
794 
795     set_buffer_lines(curbuf, lnum, FALSE, &argvars[1], rettv);
796 }
797 #endif  // FEAT_EVAL
798 
799 #if defined(FEAT_JOB_CHANNEL) \
800 	|| defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) \
801 	|| defined(PROTO)
802 /*
803  * Make "buf" the current buffer.  restore_buffer() MUST be called to undo.
804  * No autocommands will be executed.  Use aucmd_prepbuf() if there are any.
805  */
806     void
807 switch_buffer(bufref_T *save_curbuf, buf_T *buf)
808 {
809     block_autocmds();
810 #ifdef FEAT_FOLDING
811     ++disable_fold_update;
812 #endif
813     set_bufref(save_curbuf, curbuf);
814     --curbuf->b_nwindows;
815     curbuf = buf;
816     curwin->w_buffer = buf;
817     ++curbuf->b_nwindows;
818 }
819 
820 /*
821  * Restore the current buffer after using switch_buffer().
822  */
823     void
824 restore_buffer(bufref_T *save_curbuf)
825 {
826     unblock_autocmds();
827 #ifdef FEAT_FOLDING
828     --disable_fold_update;
829 #endif
830     // Check for valid buffer, just in case.
831     if (bufref_valid(save_curbuf))
832     {
833 	--curbuf->b_nwindows;
834 	curwin->w_buffer = save_curbuf->br_buf;
835 	curbuf = save_curbuf->br_buf;
836 	++curbuf->b_nwindows;
837     }
838 }
839 
840 /*
841  * Find a window for buffer "buf".
842  * If found OK is returned and "wp" and "tp" are set to the window and tabpage.
843  * If not found FAIL is returned.
844  */
845     static int
846 find_win_for_buf(
847     buf_T     *buf,
848     win_T     **wp,
849     tabpage_T **tp)
850 {
851     FOR_ALL_TAB_WINDOWS(*tp, *wp)
852 	if ((*wp)->w_buffer == buf)
853 	    return OK;
854     return FAIL;
855 }
856 
857 /*
858  * Find a window that contains "buf" and switch to it.
859  * If there is no such window, use the current window and change "curbuf".
860  * Caller must initialize save_curbuf to NULL.
861  * restore_win_for_buf() MUST be called later!
862  */
863     void
864 switch_to_win_for_buf(
865     buf_T	*buf,
866     win_T	**save_curwinp,
867     tabpage_T	**save_curtabp,
868     bufref_T	*save_curbuf)
869 {
870     win_T	*wp;
871     tabpage_T	*tp;
872 
873     if (find_win_for_buf(buf, &wp, &tp) == FAIL)
874 	switch_buffer(save_curbuf, buf);
875     else if (switch_win(save_curwinp, save_curtabp, wp, tp, TRUE) == FAIL)
876     {
877 	restore_win(*save_curwinp, *save_curtabp, TRUE);
878 	switch_buffer(save_curbuf, buf);
879     }
880 }
881 
882     void
883 restore_win_for_buf(
884     win_T	*save_curwin,
885     tabpage_T	*save_curtab,
886     bufref_T	*save_curbuf)
887 {
888     if (save_curbuf->br_buf == NULL)
889 	restore_win(save_curwin, save_curtab, TRUE);
890     else
891 	restore_buffer(save_curbuf);
892 }
893 #endif
894