xref: /vim-8.2.3635/src/evalbuffer.c (revision 3b0ef8cf)
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 = (char_u *)"";
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 (wip = curbuf->b_wininfo; wip != NULL; wip = wip->wi_next)
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 	range_list_materialize(l);
180 	li = l->lv_first;
181     }
182     else
183 	line = tv_get_string_chk(lines);
184 
185     // default result is zero == OK
186     for (;;)
187     {
188 	if (l != NULL)
189 	{
190 	    // list argument, get next string
191 	    if (li == NULL)
192 		break;
193 	    line = tv_get_string_chk(&li->li_tv);
194 	    li = li->li_next;
195 	}
196 
197 	rettv->vval.v_number = 1;	// FAIL
198 	if (line == NULL || lnum > curbuf->b_ml.ml_line_count + 1)
199 	    break;
200 
201 	// When coming here from Insert mode, sync undo, so that this can be
202 	// undone separately from what was previously inserted.
203 	if (u_sync_once == 2)
204 	{
205 	    u_sync_once = 1; // notify that u_sync() was called
206 	    u_sync(TRUE);
207 	}
208 
209 	if (!append && lnum <= curbuf->b_ml.ml_line_count)
210 	{
211 	    // Existing line, replace it.
212 	    // Removes any existing text properties.
213 	    if (u_savesub(lnum) == OK && ml_replace_len(
214 		      lnum, line, (colnr_T)STRLEN(line) + 1, TRUE, TRUE) == OK)
215 	    {
216 		changed_bytes(lnum, 0);
217 		if (is_curbuf && lnum == curwin->w_cursor.lnum)
218 		    check_cursor_col();
219 		rettv->vval.v_number = 0;	// OK
220 	    }
221 	}
222 	else if (added > 0 || u_save(lnum - 1, lnum) == OK)
223 	{
224 	    // append the line
225 	    ++added;
226 	    if (ml_append(lnum - 1, line, (colnr_T)0, FALSE) == OK)
227 		rettv->vval.v_number = 0;	// OK
228 	}
229 
230 	if (l == NULL)			// only one string argument
231 	    break;
232 	++lnum;
233     }
234 
235     if (added > 0)
236     {
237 	win_T	    *wp;
238 	tabpage_T   *tp;
239 
240 	appended_lines_mark(append_lnum, added);
241 
242 	// Only adjust the cursor for buffers other than the current, unless it
243 	// is the current window.  For curbuf and other windows it has been
244 	// done in mark_adjust_internal().
245 	FOR_ALL_TAB_WINDOWS(tp, wp)
246 	    if (wp->w_buffer == buf
247 		    && (wp->w_buffer != curbuf || wp == curwin)
248 		    && wp->w_cursor.lnum > append_lnum)
249 		wp->w_cursor.lnum += added;
250 	check_cursor_col();
251 	update_topline();
252     }
253 
254     if (!is_curbuf)
255     {
256 	curbuf = curbuf_save;
257 	curwin = curwin_save;
258     }
259 }
260 
261 /*
262  * "append(lnum, string/list)" function
263  */
264     void
265 f_append(typval_T *argvars, typval_T *rettv)
266 {
267     linenr_T	lnum = tv_get_lnum(&argvars[0]);
268 
269     set_buffer_lines(curbuf, lnum, TRUE, &argvars[1], rettv);
270 }
271 
272 /*
273  * "appendbufline(buf, lnum, string/list)" function
274  */
275     void
276 f_appendbufline(typval_T *argvars, typval_T *rettv)
277 {
278     linenr_T	lnum;
279     buf_T	*buf;
280 
281     buf = tv_get_buf(&argvars[0], FALSE);
282     if (buf == NULL)
283 	rettv->vval.v_number = 1; // FAIL
284     else
285     {
286 	lnum = tv_get_lnum_buf(&argvars[1], buf);
287 	set_buffer_lines(buf, lnum, TRUE, &argvars[2], rettv);
288     }
289 }
290 
291 /*
292  * "bufadd(expr)" function
293  */
294     void
295 f_bufadd(typval_T *argvars, typval_T *rettv)
296 {
297     char_u *name = tv_get_string(&argvars[0]);
298 
299     rettv->vval.v_number = buflist_add(*name == NUL ? NULL : name, 0);
300 }
301 
302 /*
303  * "bufexists(expr)" function
304  */
305     void
306 f_bufexists(typval_T *argvars, typval_T *rettv)
307 {
308     rettv->vval.v_number = (find_buffer(&argvars[0]) != NULL);
309 }
310 
311 /*
312  * "buflisted(expr)" function
313  */
314     void
315 f_buflisted(typval_T *argvars, typval_T *rettv)
316 {
317     buf_T	*buf;
318 
319     buf = find_buffer(&argvars[0]);
320     rettv->vval.v_number = (buf != NULL && buf->b_p_bl);
321 }
322 
323 /*
324  * "bufload(expr)" function
325  */
326     void
327 f_bufload(typval_T *argvars, typval_T *rettv UNUSED)
328 {
329     buf_T	*buf = get_buf_arg(&argvars[0]);
330 
331     if (buf != NULL)
332 	buffer_ensure_loaded(buf);
333 }
334 
335 /*
336  * "bufloaded(expr)" function
337  */
338     void
339 f_bufloaded(typval_T *argvars, typval_T *rettv)
340 {
341     buf_T	*buf;
342 
343     buf = find_buffer(&argvars[0]);
344     rettv->vval.v_number = (buf != NULL && buf->b_ml.ml_mfp != NULL);
345 }
346 
347 /*
348  * "bufname(expr)" function
349  */
350     void
351 f_bufname(typval_T *argvars, typval_T *rettv)
352 {
353     buf_T	*buf;
354 
355     if (argvars[0].v_type == VAR_UNKNOWN)
356 	buf = curbuf;
357     else
358     {
359 	(void)tv_get_number(&argvars[0]);	// issue errmsg if type error
360 	++emsg_off;
361 	buf = tv_get_buf(&argvars[0], FALSE);
362 	--emsg_off;
363     }
364     rettv->v_type = VAR_STRING;
365     if (buf != NULL && buf->b_fname != NULL)
366 	rettv->vval.v_string = vim_strsave(buf->b_fname);
367     else
368 	rettv->vval.v_string = NULL;
369 }
370 
371 /*
372  * "bufnr(expr)" function
373  */
374     void
375 f_bufnr(typval_T *argvars, typval_T *rettv)
376 {
377     buf_T	*buf;
378     int		error = FALSE;
379     char_u	*name;
380 
381     if (argvars[0].v_type == VAR_UNKNOWN)
382 	buf = curbuf;
383     else
384     {
385 	(void)tv_get_number(&argvars[0]);    // issue errmsg if type error
386 	++emsg_off;
387 	buf = tv_get_buf(&argvars[0], FALSE);
388 	--emsg_off;
389     }
390 
391     // If the buffer isn't found and the second argument is not zero create a
392     // new buffer.
393     if (buf == NULL
394 	    && argvars[1].v_type != VAR_UNKNOWN
395 	    && tv_get_number_chk(&argvars[1], &error) != 0
396 	    && !error
397 	    && (name = tv_get_string_chk(&argvars[0])) != NULL
398 	    && !error)
399 	buf = buflist_new(name, NULL, (linenr_T)1, 0);
400 
401     if (buf != NULL)
402 	rettv->vval.v_number = buf->b_fnum;
403     else
404 	rettv->vval.v_number = -1;
405 }
406 
407     static void
408 buf_win_common(typval_T *argvars, typval_T *rettv, int get_nr)
409 {
410     win_T	*wp;
411     int		winnr = 0;
412     buf_T	*buf;
413 
414     (void)tv_get_number(&argvars[0]);	    // issue errmsg if type error
415     ++emsg_off;
416     buf = tv_get_buf(&argvars[0], TRUE);
417     FOR_ALL_WINDOWS(wp)
418     {
419 	++winnr;
420 	if (wp->w_buffer == buf)
421 	    break;
422     }
423     rettv->vval.v_number = (wp != NULL ? (get_nr ? winnr : wp->w_id) : -1);
424     --emsg_off;
425 }
426 
427 /*
428  * "bufwinid(nr)" function
429  */
430     void
431 f_bufwinid(typval_T *argvars, typval_T *rettv)
432 {
433     buf_win_common(argvars, rettv, FALSE);
434 }
435 
436 /*
437  * "bufwinnr(nr)" function
438  */
439     void
440 f_bufwinnr(typval_T *argvars, typval_T *rettv)
441 {
442     buf_win_common(argvars, rettv, TRUE);
443 }
444 
445 /*
446  * "deletebufline()" function
447  */
448     void
449 f_deletebufline(typval_T *argvars, typval_T *rettv)
450 {
451     buf_T	*buf;
452     linenr_T	first, last;
453     linenr_T	lnum;
454     long	count;
455     int		is_curbuf;
456     buf_T	*curbuf_save = NULL;
457     win_T	*curwin_save = NULL;
458     tabpage_T	*tp;
459     win_T	*wp;
460 
461     buf = tv_get_buf(&argvars[0], FALSE);
462     if (buf == NULL)
463     {
464 	rettv->vval.v_number = 1; // FAIL
465 	return;
466     }
467     is_curbuf = buf == curbuf;
468 
469     first = tv_get_lnum_buf(&argvars[1], buf);
470     if (argvars[2].v_type != VAR_UNKNOWN)
471 	last = tv_get_lnum_buf(&argvars[2], buf);
472     else
473 	last = first;
474 
475     if (buf->b_ml.ml_mfp == NULL || first < 1
476 			   || first > buf->b_ml.ml_line_count || last < first)
477     {
478 	rettv->vval.v_number = 1;	// FAIL
479 	return;
480     }
481 
482     if (!is_curbuf)
483     {
484 	curbuf_save = curbuf;
485 	curwin_save = curwin;
486 	curbuf = buf;
487 	find_win_for_curbuf();
488     }
489     if (last > curbuf->b_ml.ml_line_count)
490 	last = curbuf->b_ml.ml_line_count;
491     count = last - first + 1;
492 
493     // When coming here from Insert mode, sync undo, so that this can be
494     // undone separately from what was previously inserted.
495     if (u_sync_once == 2)
496     {
497 	u_sync_once = 1; // notify that u_sync() was called
498 	u_sync(TRUE);
499     }
500 
501     if (u_save(first - 1, last + 1) == FAIL)
502     {
503 	rettv->vval.v_number = 1;	// FAIL
504 	return;
505     }
506 
507     for (lnum = first; lnum <= last; ++lnum)
508 	ml_delete(first, TRUE);
509 
510     FOR_ALL_TAB_WINDOWS(tp, wp)
511 	if (wp->w_buffer == buf)
512 	{
513 	    if (wp->w_cursor.lnum > last)
514 		wp->w_cursor.lnum -= count;
515 	    else if (wp->w_cursor.lnum> first)
516 		wp->w_cursor.lnum = first;
517 	    if (wp->w_cursor.lnum > wp->w_buffer->b_ml.ml_line_count)
518 		wp->w_cursor.lnum = wp->w_buffer->b_ml.ml_line_count;
519 	}
520     check_cursor_col();
521     deleted_lines_mark(first, count);
522 
523     if (!is_curbuf)
524     {
525 	curbuf = curbuf_save;
526 	curwin = curwin_save;
527     }
528 }
529 
530 /*
531  * Returns buffer options, variables and other attributes in a dictionary.
532  */
533     static dict_T *
534 get_buffer_info(buf_T *buf)
535 {
536     dict_T	*dict;
537     tabpage_T	*tp;
538     win_T	*wp;
539     list_T	*windows;
540 
541     dict = dict_alloc();
542     if (dict == NULL)
543 	return NULL;
544 
545     dict_add_number(dict, "bufnr", buf->b_fnum);
546     dict_add_string(dict, "name", buf->b_ffname);
547     dict_add_number(dict, "lnum", buf == curbuf ? curwin->w_cursor.lnum
548 						     : buflist_findlnum(buf));
549     dict_add_number(dict, "linecount", buf->b_ml.ml_line_count);
550     dict_add_number(dict, "loaded", buf->b_ml.ml_mfp != NULL);
551     dict_add_number(dict, "listed", buf->b_p_bl);
552     dict_add_number(dict, "changed", bufIsChanged(buf));
553     dict_add_number(dict, "changedtick", CHANGEDTICK(buf));
554     dict_add_number(dict, "hidden",
555 			    buf->b_ml.ml_mfp != NULL && buf->b_nwindows == 0);
556 
557     // Get a reference to buffer variables
558     dict_add_dict(dict, "variables", buf->b_vars);
559 
560     // List of windows displaying this buffer
561     windows = list_alloc();
562     if (windows != NULL)
563     {
564 	FOR_ALL_TAB_WINDOWS(tp, wp)
565 	    if (wp->w_buffer == buf)
566 		list_append_number(windows, (varnumber_T)wp->w_id);
567 	dict_add_list(dict, "windows", windows);
568     }
569 
570 #ifdef FEAT_PROP_POPUP
571     // List of popup windows displaying this buffer
572     windows = list_alloc();
573     if (windows != NULL)
574     {
575 	for (wp = first_popupwin; wp != NULL; wp = wp->w_next)
576 	    if (wp->w_buffer == buf)
577 		list_append_number(windows, (varnumber_T)wp->w_id);
578 	FOR_ALL_TABPAGES(tp)
579 	    for (wp = tp->tp_first_popupwin; wp != NULL; wp = wp->w_next)
580 		if (wp->w_buffer == buf)
581 		    list_append_number(windows, (varnumber_T)wp->w_id);
582 
583 	dict_add_list(dict, "popups", windows);
584     }
585 #endif
586 
587 #ifdef FEAT_SIGNS
588     if (buf->b_signlist != NULL)
589     {
590 	// List of signs placed in this buffer
591 	list_T	*signs = list_alloc();
592 	if (signs != NULL)
593 	{
594 	    get_buffer_signs(buf, signs);
595 	    dict_add_list(dict, "signs", signs);
596 	}
597     }
598 #endif
599 
600 #ifdef FEAT_VIMINFO
601     dict_add_number(dict, "lastused", buf->b_last_used);
602 #endif
603 
604     return dict;
605 }
606 
607 /*
608  * "getbufinfo()" function
609  */
610     void
611 f_getbufinfo(typval_T *argvars, typval_T *rettv)
612 {
613     buf_T	*buf = NULL;
614     buf_T	*argbuf = NULL;
615     dict_T	*d;
616     int		filtered = FALSE;
617     int		sel_buflisted = FALSE;
618     int		sel_bufloaded = FALSE;
619     int		sel_bufmodified = FALSE;
620 
621     if (rettv_list_alloc(rettv) != OK)
622 	return;
623 
624     // List of all the buffers or selected buffers
625     if (argvars[0].v_type == VAR_DICT)
626     {
627 	dict_T	*sel_d = argvars[0].vval.v_dict;
628 
629 	if (sel_d != NULL)
630 	{
631 	    dictitem_T	*di;
632 
633 	    filtered = TRUE;
634 
635 	    di = dict_find(sel_d, (char_u *)"buflisted", -1);
636 	    if (di != NULL && tv_get_number(&di->di_tv))
637 		sel_buflisted = TRUE;
638 
639 	    di = dict_find(sel_d, (char_u *)"bufloaded", -1);
640 	    if (di != NULL && tv_get_number(&di->di_tv))
641 		sel_bufloaded = TRUE;
642 
643 	    di = dict_find(sel_d, (char_u *)"bufmodified", -1);
644 	    if (di != NULL && tv_get_number(&di->di_tv))
645 		sel_bufmodified = TRUE;
646 	}
647     }
648     else if (argvars[0].v_type != VAR_UNKNOWN)
649     {
650 	// Information about one buffer.  Argument specifies the buffer
651 	(void)tv_get_number(&argvars[0]);   // issue errmsg if type error
652 	++emsg_off;
653 	argbuf = tv_get_buf(&argvars[0], FALSE);
654 	--emsg_off;
655 	if (argbuf == NULL)
656 	    return;
657     }
658 
659     // Return information about all the buffers or a specified buffer
660     FOR_ALL_BUFFERS(buf)
661     {
662 	if (argbuf != NULL && argbuf != buf)
663 	    continue;
664 	if (filtered && ((sel_bufloaded && buf->b_ml.ml_mfp == NULL)
665 			|| (sel_buflisted && !buf->b_p_bl)
666 			|| (sel_bufmodified && !buf->b_changed)))
667 	    continue;
668 
669 	d = get_buffer_info(buf);
670 	if (d != NULL)
671 	    list_append_dict(rettv->vval.v_list, d);
672 	if (argbuf != NULL)
673 	    return;
674     }
675 }
676 
677 /*
678  * Get line or list of lines from buffer "buf" into "rettv".
679  * Return a range (from start to end) of lines in rettv from the specified
680  * buffer.
681  * If 'retlist' is TRUE, then the lines are returned as a Vim List.
682  */
683     static void
684 get_buffer_lines(
685     buf_T	*buf,
686     linenr_T	start,
687     linenr_T	end,
688     int		retlist,
689     typval_T	*rettv)
690 {
691     char_u	*p;
692 
693     if (retlist)
694     {
695 	if (rettv_list_alloc(rettv) == FAIL)
696 	    return;
697     }
698     else
699     {
700 	rettv->v_type = VAR_STRING;
701 	rettv->vval.v_string = NULL;
702     }
703 
704     if (buf == NULL || buf->b_ml.ml_mfp == NULL || start < 0)
705 	return;
706 
707     if (!retlist)
708     {
709 	if (start >= 1 && start <= buf->b_ml.ml_line_count)
710 	    p = ml_get_buf(buf, start, FALSE);
711 	else
712 	    p = (char_u *)"";
713 	rettv->vval.v_string = vim_strsave(p);
714     }
715     else
716     {
717 	if (end < start)
718 	    return;
719 
720 	if (start < 1)
721 	    start = 1;
722 	if (end > buf->b_ml.ml_line_count)
723 	    end = buf->b_ml.ml_line_count;
724 	while (start <= end)
725 	    if (list_append_string(rettv->vval.v_list,
726 				 ml_get_buf(buf, start++, FALSE), -1) == FAIL)
727 		break;
728     }
729 }
730 
731 /*
732  * "getbufline()" function
733  */
734     void
735 f_getbufline(typval_T *argvars, typval_T *rettv)
736 {
737     linenr_T	lnum;
738     linenr_T	end;
739     buf_T	*buf;
740 
741     (void)tv_get_number(&argvars[0]);	    // issue errmsg if type error
742     ++emsg_off;
743     buf = tv_get_buf(&argvars[0], FALSE);
744     --emsg_off;
745 
746     lnum = tv_get_lnum_buf(&argvars[1], buf);
747     if (argvars[2].v_type == VAR_UNKNOWN)
748 	end = lnum;
749     else
750 	end = tv_get_lnum_buf(&argvars[2], buf);
751 
752     get_buffer_lines(buf, lnum, end, TRUE, rettv);
753 }
754 
755 /*
756  * "getline(lnum, [end])" function
757  */
758     void
759 f_getline(typval_T *argvars, typval_T *rettv)
760 {
761     linenr_T	lnum;
762     linenr_T	end;
763     int		retlist;
764 
765     lnum = tv_get_lnum(argvars);
766     if (argvars[1].v_type == VAR_UNKNOWN)
767     {
768 	end = 0;
769 	retlist = FALSE;
770     }
771     else
772     {
773 	end = tv_get_lnum(&argvars[1]);
774 	retlist = TRUE;
775     }
776 
777     get_buffer_lines(curbuf, lnum, end, retlist, rettv);
778 }
779 
780 /*
781  * "setbufline()" function
782  */
783     void
784 f_setbufline(typval_T *argvars, typval_T *rettv)
785 {
786     linenr_T	lnum;
787     buf_T	*buf;
788 
789     buf = tv_get_buf(&argvars[0], FALSE);
790     if (buf == NULL)
791 	rettv->vval.v_number = 1; // FAIL
792     else
793     {
794 	lnum = tv_get_lnum_buf(&argvars[1], buf);
795 	set_buffer_lines(buf, lnum, FALSE, &argvars[2], rettv);
796     }
797 }
798 
799 /*
800  * "setline()" function
801  */
802     void
803 f_setline(typval_T *argvars, typval_T *rettv)
804 {
805     linenr_T	lnum = tv_get_lnum(&argvars[0]);
806 
807     set_buffer_lines(curbuf, lnum, FALSE, &argvars[1], rettv);
808 }
809 #endif  // FEAT_EVAL
810 
811 #if defined(FEAT_JOB_CHANNEL) \
812 	|| defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) \
813 	|| defined(PROTO)
814 /*
815  * Make "buf" the current buffer.  restore_buffer() MUST be called to undo.
816  * No autocommands will be executed.  Use aucmd_prepbuf() if there are any.
817  */
818     void
819 switch_buffer(bufref_T *save_curbuf, buf_T *buf)
820 {
821     block_autocmds();
822     set_bufref(save_curbuf, curbuf);
823     --curbuf->b_nwindows;
824     curbuf = buf;
825     curwin->w_buffer = buf;
826     ++curbuf->b_nwindows;
827 }
828 
829 /*
830  * Restore the current buffer after using switch_buffer().
831  */
832     void
833 restore_buffer(bufref_T *save_curbuf)
834 {
835     unblock_autocmds();
836     // Check for valid buffer, just in case.
837     if (bufref_valid(save_curbuf))
838     {
839 	--curbuf->b_nwindows;
840 	curwin->w_buffer = save_curbuf->br_buf;
841 	curbuf = save_curbuf->br_buf;
842 	++curbuf->b_nwindows;
843     }
844 }
845 
846 /*
847  * Find a window for buffer "buf".
848  * If found OK is returned and "wp" and "tp" are set to the window and tabpage.
849  * If not found FAIL is returned.
850  */
851     static int
852 find_win_for_buf(
853     buf_T     *buf,
854     win_T     **wp,
855     tabpage_T **tp)
856 {
857     FOR_ALL_TAB_WINDOWS(*tp, *wp)
858 	if ((*wp)->w_buffer == buf)
859 	    return OK;
860     return FAIL;
861 }
862 
863 /*
864  * Find a window that contains "buf" and switch to it.
865  * If there is no such window, use the current window and change "curbuf".
866  * Caller must initialize save_curbuf to NULL.
867  * restore_win_for_buf() MUST be called later!
868  */
869     void
870 switch_to_win_for_buf(
871     buf_T	*buf,
872     win_T	**save_curwinp,
873     tabpage_T	**save_curtabp,
874     bufref_T	*save_curbuf)
875 {
876     win_T	*wp;
877     tabpage_T	*tp;
878 
879     if (find_win_for_buf(buf, &wp, &tp) == FAIL)
880 	switch_buffer(save_curbuf, buf);
881     else if (switch_win(save_curwinp, save_curtabp, wp, tp, TRUE) == FAIL)
882     {
883 	restore_win(*save_curwinp, *save_curtabp, TRUE);
884 	switch_buffer(save_curbuf, buf);
885     }
886 }
887 
888     void
889 restore_win_for_buf(
890     win_T	*save_curwin,
891     tabpage_T	*save_curtab,
892     bufref_T	*save_curbuf)
893 {
894     if (save_curbuf->br_buf == NULL)
895 	restore_win(save_curwin, save_curtab, TRUE);
896     else
897 	restore_buffer(save_curbuf);
898 }
899 #endif
900