xref: /openbsd-src/usr.bin/tmux/window.c (revision 0b5493cb0c742202428c9cd6ec8d6e309804d203)
1 /* $OpenBSD: window.c,v 1.286 2023/07/10 09:24:53 nicm Exp $ */
2 
3 /*
4  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/ioctl.h>
21 
22 #include <ctype.h>
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <fnmatch.h>
26 #include <regex.h>
27 #include <signal.h>
28 #include <stdint.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <time.h>
32 #include <unistd.h>
33 #include <util.h>
34 #include <vis.h>
35 
36 #include "tmux.h"
37 
38 /*
39  * Each window is attached to a number of panes, each of which is a pty. This
40  * file contains code to handle them.
41  *
42  * A pane has two buffers attached, these are filled and emptied by the main
43  * server poll loop. Output data is received from pty's in screen format,
44  * translated and returned as a series of escape sequences and strings via
45  * input_parse (in input.c). Input data is received as key codes and written
46  * directly via input_key.
47  *
48  * Each pane also has a "virtual" screen (screen.c) which contains the current
49  * state and is redisplayed when the window is reattached to a client.
50  *
51  * Windows are stored directly on a global array and wrapped in any number of
52  * winlink structs to be linked onto local session RB trees. A reference count
53  * is maintained and a window removed from the global list and destroyed when
54  * it reaches zero.
55  */
56 
57 /* Global window list. */
58 struct windows windows;
59 
60 /* Global panes tree. */
61 struct window_pane_tree all_window_panes;
62 static u_int	next_window_pane_id;
63 static u_int	next_window_id;
64 static u_int	next_active_point;
65 
66 struct window_pane_input_data {
67 	struct cmdq_item	*item;
68 	u_int			 wp;
69 	struct client_file	*file;
70 };
71 
72 static struct window_pane *window_pane_create(struct window *, u_int, u_int,
73 		    u_int);
74 static void	window_pane_destroy(struct window_pane *);
75 
76 RB_GENERATE(windows, window, entry, window_cmp);
77 RB_GENERATE(winlinks, winlink, entry, winlink_cmp);
78 RB_GENERATE(window_pane_tree, window_pane, tree_entry, window_pane_cmp);
79 
80 int
81 window_cmp(struct window *w1, struct window *w2)
82 {
83 	return (w1->id - w2->id);
84 }
85 
86 int
87 winlink_cmp(struct winlink *wl1, struct winlink *wl2)
88 {
89 	return (wl1->idx - wl2->idx);
90 }
91 
92 int
93 window_pane_cmp(struct window_pane *wp1, struct window_pane *wp2)
94 {
95 	return (wp1->id - wp2->id);
96 }
97 
98 struct winlink *
99 winlink_find_by_window(struct winlinks *wwl, struct window *w)
100 {
101 	struct winlink	*wl;
102 
103 	RB_FOREACH(wl, winlinks, wwl) {
104 		if (wl->window == w)
105 			return (wl);
106 	}
107 
108 	return (NULL);
109 }
110 
111 struct winlink *
112 winlink_find_by_index(struct winlinks *wwl, int idx)
113 {
114 	struct winlink	wl;
115 
116 	if (idx < 0)
117 		fatalx("bad index");
118 
119 	wl.idx = idx;
120 	return (RB_FIND(winlinks, wwl, &wl));
121 }
122 
123 struct winlink *
124 winlink_find_by_window_id(struct winlinks *wwl, u_int id)
125 {
126 	struct winlink *wl;
127 
128 	RB_FOREACH(wl, winlinks, wwl) {
129 		if (wl->window->id == id)
130 			return (wl);
131 	}
132 	return (NULL);
133 }
134 
135 static int
136 winlink_next_index(struct winlinks *wwl, int idx)
137 {
138 	int	i;
139 
140 	i = idx;
141 	do {
142 		if (winlink_find_by_index(wwl, i) == NULL)
143 			return (i);
144 		if (i == INT_MAX)
145 			i = 0;
146 		else
147 			i++;
148 	} while (i != idx);
149 	return (-1);
150 }
151 
152 u_int
153 winlink_count(struct winlinks *wwl)
154 {
155 	struct winlink	*wl;
156 	u_int		 n;
157 
158 	n = 0;
159 	RB_FOREACH(wl, winlinks, wwl)
160 		n++;
161 
162 	return (n);
163 }
164 
165 struct winlink *
166 winlink_add(struct winlinks *wwl, int idx)
167 {
168 	struct winlink	*wl;
169 
170 	if (idx < 0) {
171 		if ((idx = winlink_next_index(wwl, -idx - 1)) == -1)
172 			return (NULL);
173 	} else if (winlink_find_by_index(wwl, idx) != NULL)
174 		return (NULL);
175 
176 	wl = xcalloc(1, sizeof *wl);
177 	wl->idx = idx;
178 	RB_INSERT(winlinks, wwl, wl);
179 
180 	return (wl);
181 }
182 
183 void
184 winlink_set_window(struct winlink *wl, struct window *w)
185 {
186 	if (wl->window != NULL) {
187 		TAILQ_REMOVE(&wl->window->winlinks, wl, wentry);
188 		window_remove_ref(wl->window, __func__);
189 	}
190 	TAILQ_INSERT_TAIL(&w->winlinks, wl, wentry);
191 	wl->window = w;
192 	window_add_ref(w, __func__);
193 }
194 
195 void
196 winlink_remove(struct winlinks *wwl, struct winlink *wl)
197 {
198 	struct window	*w = wl->window;
199 
200 	if (w != NULL) {
201 		TAILQ_REMOVE(&w->winlinks, wl, wentry);
202 		window_remove_ref(w, __func__);
203 	}
204 
205 	RB_REMOVE(winlinks, wwl, wl);
206 	free(wl);
207 }
208 
209 struct winlink *
210 winlink_next(struct winlink *wl)
211 {
212 	return (RB_NEXT(winlinks, wwl, wl));
213 }
214 
215 struct winlink *
216 winlink_previous(struct winlink *wl)
217 {
218 	return (RB_PREV(winlinks, wwl, wl));
219 }
220 
221 struct winlink *
222 winlink_next_by_number(struct winlink *wl, struct session *s, int n)
223 {
224 	for (; n > 0; n--) {
225 		if ((wl = RB_NEXT(winlinks, wwl, wl)) == NULL)
226 			wl = RB_MIN(winlinks, &s->windows);
227 	}
228 
229 	return (wl);
230 }
231 
232 struct winlink *
233 winlink_previous_by_number(struct winlink *wl, struct session *s, int n)
234 {
235 	for (; n > 0; n--) {
236 		if ((wl = RB_PREV(winlinks, wwl, wl)) == NULL)
237 			wl = RB_MAX(winlinks, &s->windows);
238 	}
239 
240 	return (wl);
241 }
242 
243 void
244 winlink_stack_push(struct winlink_stack *stack, struct winlink *wl)
245 {
246 	if (wl == NULL)
247 		return;
248 
249 	winlink_stack_remove(stack, wl);
250 	TAILQ_INSERT_HEAD(stack, wl, sentry);
251 	wl->flags |= WINLINK_VISITED;
252 }
253 
254 void
255 winlink_stack_remove(struct winlink_stack *stack, struct winlink *wl)
256 {
257 	if (wl != NULL && (wl->flags & WINLINK_VISITED)) {
258 		TAILQ_REMOVE(stack, wl, sentry);
259 		wl->flags &= ~WINLINK_VISITED;
260 	}
261 }
262 
263 struct window *
264 window_find_by_id_str(const char *s)
265 {
266 	const char	*errstr;
267 	u_int		 id;
268 
269 	if (*s != '@')
270 		return (NULL);
271 
272 	id = strtonum(s + 1, 0, UINT_MAX, &errstr);
273 	if (errstr != NULL)
274 		return (NULL);
275 	return (window_find_by_id(id));
276 }
277 
278 struct window *
279 window_find_by_id(u_int id)
280 {
281 	struct window	w;
282 
283 	w.id = id;
284 	return (RB_FIND(windows, &windows, &w));
285 }
286 
287 void
288 window_update_activity(struct window *w)
289 {
290 	gettimeofday(&w->activity_time, NULL);
291 	alerts_queue(w, WINDOW_ACTIVITY);
292 }
293 
294 struct window *
295 window_create(u_int sx, u_int sy, u_int xpixel, u_int ypixel)
296 {
297 	struct window	*w;
298 
299 	if (xpixel == 0)
300 		xpixel = DEFAULT_XPIXEL;
301 	if (ypixel == 0)
302 		ypixel = DEFAULT_YPIXEL;
303 
304 	w = xcalloc(1, sizeof *w);
305 	w->name = xstrdup("");
306 	w->flags = 0;
307 
308 	TAILQ_INIT(&w->panes);
309 	TAILQ_INIT(&w->last_panes);
310 	w->active = NULL;
311 
312 	w->lastlayout = -1;
313 	w->layout_root = NULL;
314 
315 	w->sx = sx;
316 	w->sy = sy;
317 	w->manual_sx = sx;
318 	w->manual_sy = sy;
319 	w->xpixel = xpixel;
320 	w->ypixel = ypixel;
321 
322 	w->options = options_create(global_w_options);
323 
324 	w->references = 0;
325 	TAILQ_INIT(&w->winlinks);
326 
327 	w->id = next_window_id++;
328 	RB_INSERT(windows, &windows, w);
329 
330 	window_set_fill_character(w);
331 	window_update_activity(w);
332 
333 	log_debug("%s: @%u create %ux%u (%ux%u)", __func__, w->id, sx, sy,
334 	    w->xpixel, w->ypixel);
335 	return (w);
336 }
337 
338 static void
339 window_destroy(struct window *w)
340 {
341 	log_debug("window @%u destroyed (%d references)", w->id, w->references);
342 
343 	RB_REMOVE(windows, &windows, w);
344 
345 	if (w->layout_root != NULL)
346 		layout_free_cell(w->layout_root);
347 	if (w->saved_layout_root != NULL)
348 		layout_free_cell(w->saved_layout_root);
349 	free(w->old_layout);
350 
351 	window_destroy_panes(w);
352 
353 	if (event_initialized(&w->name_event))
354 		evtimer_del(&w->name_event);
355 
356 	if (event_initialized(&w->alerts_timer))
357 		evtimer_del(&w->alerts_timer);
358 	if (event_initialized(&w->offset_timer))
359 		event_del(&w->offset_timer);
360 
361 	options_free(w->options);
362 	free(w->fill_character);
363 
364 	free(w->name);
365 	free(w);
366 }
367 
368 int
369 window_pane_destroy_ready(struct window_pane *wp)
370 {
371 	int	n;
372 
373 	if (wp->pipe_fd != -1) {
374 		if (EVBUFFER_LENGTH(wp->pipe_event->output) != 0)
375 			return (0);
376 		if (ioctl(wp->fd, FIONREAD, &n) != -1 && n > 0)
377 			return (0);
378 	}
379 
380 	if (~wp->flags & PANE_EXITED)
381 		return (0);
382 	return (1);
383 }
384 
385 void
386 window_add_ref(struct window *w, const char *from)
387 {
388 	w->references++;
389 	log_debug("%s: @%u %s, now %d", __func__, w->id, from, w->references);
390 }
391 
392 void
393 window_remove_ref(struct window *w, const char *from)
394 {
395 	w->references--;
396 	log_debug("%s: @%u %s, now %d", __func__, w->id, from, w->references);
397 
398 	if (w->references == 0)
399 		window_destroy(w);
400 }
401 
402 void
403 window_set_name(struct window *w, const char *new_name)
404 {
405 	free(w->name);
406 	utf8_stravis(&w->name, new_name, VIS_OCTAL|VIS_CSTYLE|VIS_TAB|VIS_NL);
407 	notify_window("window-renamed", w);
408 }
409 
410 void
411 window_resize(struct window *w, u_int sx, u_int sy, int xpixel, int ypixel)
412 {
413 	if (xpixel == 0)
414 		xpixel = DEFAULT_XPIXEL;
415 	if (ypixel == 0)
416 		ypixel = DEFAULT_YPIXEL;
417 
418 	log_debug("%s: @%u resize %ux%u (%ux%u)", __func__, w->id, sx, sy,
419 	    xpixel == -1 ? w->xpixel : (u_int)xpixel,
420 	    ypixel == -1 ? w->ypixel : (u_int)ypixel);
421 	w->sx = sx;
422 	w->sy = sy;
423 	if (xpixel != -1)
424 		w->xpixel = xpixel;
425 	if (ypixel != -1)
426 		w->ypixel = ypixel;
427 }
428 
429 void
430 window_pane_send_resize(struct window_pane *wp, u_int sx, u_int sy)
431 {
432 	struct window	*w = wp->window;
433 	struct winsize	 ws;
434 
435 	if (wp->fd == -1)
436 		return;
437 
438 	log_debug("%s: %%%u resize to %u,%u", __func__, wp->id, sx, sy);
439 
440 	memset(&ws, 0, sizeof ws);
441 	ws.ws_col = sx;
442 	ws.ws_row = sy;
443 	ws.ws_xpixel = w->xpixel * ws.ws_col;
444 	ws.ws_ypixel = w->ypixel * ws.ws_row;
445 	if (ioctl(wp->fd, TIOCSWINSZ, &ws) == -1)
446 		fatal("ioctl failed");
447 }
448 
449 int
450 window_has_pane(struct window *w, struct window_pane *wp)
451 {
452 	struct window_pane	*wp1;
453 
454 	TAILQ_FOREACH(wp1, &w->panes, entry) {
455 		if (wp1 == wp)
456 			return (1);
457 	}
458 	return (0);
459 }
460 
461 void
462 window_update_focus(struct window *w)
463 {
464 	if (w != NULL) {
465 		log_debug("%s: @%u", __func__, w->id);
466 		window_pane_update_focus(w->active);
467 	}
468 }
469 
470 void
471 window_pane_update_focus(struct window_pane *wp)
472 {
473 	struct client	*c;
474 	int		 focused = 0;
475 
476 	if (wp != NULL) {
477 		if (wp != wp->window->active)
478 			focused = 0;
479 		else {
480 			TAILQ_FOREACH(c, &clients, entry) {
481 				if (c->session != NULL &&
482 				    c->session->attached != 0 &&
483 				    (c->flags & CLIENT_FOCUSED) &&
484 				    c->session->curw->window == wp->window) {
485 					focused = 1;
486 					break;
487 				}
488 			}
489 		}
490 		if (!focused && (wp->flags & PANE_FOCUSED)) {
491 			log_debug("%s: %%%u focus out", __func__, wp->id);
492 			if (wp->base.mode & MODE_FOCUSON)
493 				bufferevent_write(wp->event, "\033[O", 3);
494 			notify_pane("pane-focus-out", wp);
495 			wp->flags &= ~PANE_FOCUSED;
496 		} else if (focused && (~wp->flags & PANE_FOCUSED)) {
497 			log_debug("%s: %%%u focus in", __func__, wp->id);
498 			if (wp->base.mode & MODE_FOCUSON)
499 				bufferevent_write(wp->event, "\033[I", 3);
500 			notify_pane("pane-focus-in", wp);
501 			wp->flags |= PANE_FOCUSED;
502 		} else
503 			log_debug("%s: %%%u focus unchanged", __func__, wp->id);
504 	}
505 }
506 
507 int
508 window_set_active_pane(struct window *w, struct window_pane *wp, int notify)
509 {
510 	struct window_pane *lastwp;
511 
512 	log_debug("%s: pane %%%u", __func__, wp->id);
513 
514 	if (wp == w->active)
515 		return (0);
516 	lastwp = w->active;
517 
518 	window_pane_stack_remove(&w->last_panes, wp);
519 	window_pane_stack_push(&w->last_panes, lastwp);
520 
521 	w->active = wp;
522 	w->active->active_point = next_active_point++;
523 	w->active->flags |= PANE_CHANGED;
524 
525 	if (options_get_number(global_options, "focus-events")) {
526 		window_pane_update_focus(lastwp);
527 		window_pane_update_focus(w->active);
528 	}
529 
530 	tty_update_window_offset(w);
531 
532 	if (notify)
533 		notify_window("window-pane-changed", w);
534 	return (1);
535 }
536 
537 static int
538 window_pane_get_palette(struct window_pane *wp, int c)
539 {
540 	if (wp == NULL)
541 		return (-1);
542 	return (colour_palette_get(&wp->palette, c));
543 }
544 
545 void
546 window_redraw_active_switch(struct window *w, struct window_pane *wp)
547 {
548 	struct grid_cell	*gc1, *gc2;
549 	int			 c1, c2;
550 
551 	if (wp == w->active)
552 		return;
553 
554 	for (;;) {
555 		/*
556 		 * If the active and inactive styles or palettes are different,
557 		 * need to redraw the panes.
558 		 */
559 		gc1 = &wp->cached_gc;
560 		gc2 = &wp->cached_active_gc;
561 		if (!grid_cells_look_equal(gc1, gc2))
562 			wp->flags |= PANE_REDRAW;
563 		else {
564 			c1 = window_pane_get_palette(wp, gc1->fg);
565 			c2 = window_pane_get_palette(wp, gc2->fg);
566 			if (c1 != c2)
567 				wp->flags |= PANE_REDRAW;
568 			else {
569 				c1 = window_pane_get_palette(wp, gc1->bg);
570 				c2 = window_pane_get_palette(wp, gc2->bg);
571 				if (c1 != c2)
572 					wp->flags |= PANE_REDRAW;
573 			}
574 		}
575 		if (wp == w->active)
576 			break;
577 		wp = w->active;
578 	}
579 }
580 
581 struct window_pane *
582 window_get_active_at(struct window *w, u_int x, u_int y)
583 {
584 	struct window_pane	*wp;
585 
586 	TAILQ_FOREACH(wp, &w->panes, entry) {
587 		if (!window_pane_visible(wp))
588 			continue;
589 		if (x < wp->xoff || x > wp->xoff + wp->sx)
590 			continue;
591 		if (y < wp->yoff || y > wp->yoff + wp->sy)
592 			continue;
593 		return (wp);
594 	}
595 	return (NULL);
596 }
597 
598 struct window_pane *
599 window_find_string(struct window *w, const char *s)
600 {
601 	u_int	x, y, top = 0, bottom = w->sy - 1;
602 	int	status;
603 
604 	x = w->sx / 2;
605 	y = w->sy / 2;
606 
607 	status = options_get_number(w->options, "pane-border-status");
608 	if (status == PANE_STATUS_TOP)
609 		top++;
610 	else if (status == PANE_STATUS_BOTTOM)
611 		bottom--;
612 
613 	if (strcasecmp(s, "top") == 0)
614 		y = top;
615 	else if (strcasecmp(s, "bottom") == 0)
616 		y = bottom;
617 	else if (strcasecmp(s, "left") == 0)
618 		x = 0;
619 	else if (strcasecmp(s, "right") == 0)
620 		x = w->sx - 1;
621 	else if (strcasecmp(s, "top-left") == 0) {
622 		x = 0;
623 		y = top;
624 	} else if (strcasecmp(s, "top-right") == 0) {
625 		x = w->sx - 1;
626 		y = top;
627 	} else if (strcasecmp(s, "bottom-left") == 0) {
628 		x = 0;
629 		y = bottom;
630 	} else if (strcasecmp(s, "bottom-right") == 0) {
631 		x = w->sx - 1;
632 		y = bottom;
633 	} else
634 		return (NULL);
635 
636 	return (window_get_active_at(w, x, y));
637 }
638 
639 int
640 window_zoom(struct window_pane *wp)
641 {
642 	struct window		*w = wp->window;
643 	struct window_pane	*wp1;
644 
645 	if (w->flags & WINDOW_ZOOMED)
646 		return (-1);
647 
648 	if (window_count_panes(w) == 1)
649 		return (-1);
650 
651 	if (w->active != wp)
652 		window_set_active_pane(w, wp, 1);
653 
654 	TAILQ_FOREACH(wp1, &w->panes, entry) {
655 		wp1->saved_layout_cell = wp1->layout_cell;
656 		wp1->layout_cell = NULL;
657 	}
658 
659 	w->saved_layout_root = w->layout_root;
660 	layout_init(w, wp);
661 	w->flags |= WINDOW_ZOOMED;
662 	notify_window("window-layout-changed", w);
663 
664 	return (0);
665 }
666 
667 int
668 window_unzoom(struct window *w)
669 {
670 	struct window_pane	*wp;
671 
672 	if (!(w->flags & WINDOW_ZOOMED))
673 		return (-1);
674 
675 	w->flags &= ~WINDOW_ZOOMED;
676 	layout_free(w);
677 	w->layout_root = w->saved_layout_root;
678 	w->saved_layout_root = NULL;
679 
680 	TAILQ_FOREACH(wp, &w->panes, entry) {
681 		wp->layout_cell = wp->saved_layout_cell;
682 		wp->saved_layout_cell = NULL;
683 	}
684 	layout_fix_panes(w, NULL);
685 	notify_window("window-layout-changed", w);
686 
687 	return (0);
688 }
689 
690 int
691 window_push_zoom(struct window *w, int always, int flag)
692 {
693 	log_debug("%s: @%u %d", __func__, w->id,
694 	    flag && (w->flags & WINDOW_ZOOMED));
695 	if (flag && (always || (w->flags & WINDOW_ZOOMED)))
696 		w->flags |= WINDOW_WASZOOMED;
697 	else
698 		w->flags &= ~WINDOW_WASZOOMED;
699 	return (window_unzoom(w) == 0);
700 }
701 
702 int
703 window_pop_zoom(struct window *w)
704 {
705 	log_debug("%s: @%u %d", __func__, w->id,
706 	    !!(w->flags & WINDOW_WASZOOMED));
707 	if (w->flags & WINDOW_WASZOOMED)
708 		return (window_zoom(w->active) == 0);
709 	return (0);
710 }
711 
712 struct window_pane *
713 window_add_pane(struct window *w, struct window_pane *other, u_int hlimit,
714     int flags)
715 {
716 	struct window_pane	*wp;
717 
718 	if (other == NULL)
719 		other = w->active;
720 
721 	wp = window_pane_create(w, w->sx, w->sy, hlimit);
722 	if (TAILQ_EMPTY(&w->panes)) {
723 		log_debug("%s: @%u at start", __func__, w->id);
724 		TAILQ_INSERT_HEAD(&w->panes, wp, entry);
725 	} else if (flags & SPAWN_BEFORE) {
726 		log_debug("%s: @%u before %%%u", __func__, w->id, wp->id);
727 		if (flags & SPAWN_FULLSIZE)
728 			TAILQ_INSERT_HEAD(&w->panes, wp, entry);
729 		else
730 			TAILQ_INSERT_BEFORE(other, wp, entry);
731 	} else {
732 		log_debug("%s: @%u after %%%u", __func__, w->id, wp->id);
733 		if (flags & SPAWN_FULLSIZE)
734 			TAILQ_INSERT_TAIL(&w->panes, wp, entry);
735 		else
736 			TAILQ_INSERT_AFTER(&w->panes, other, wp, entry);
737 	}
738 	return (wp);
739 }
740 
741 void
742 window_lost_pane(struct window *w, struct window_pane *wp)
743 {
744 	log_debug("%s: @%u pane %%%u", __func__, w->id, wp->id);
745 
746 	if (wp == marked_pane.wp)
747 		server_clear_marked();
748 
749 	window_pane_stack_remove(&w->last_panes, wp);
750 	if (wp == w->active) {
751 		w->active = TAILQ_FIRST(&w->last_panes);
752 		if (w->active == NULL) {
753 			w->active = TAILQ_PREV(wp, window_panes, entry);
754 			if (w->active == NULL)
755 				w->active = TAILQ_NEXT(wp, entry);
756 		}
757 		if (w->active != NULL) {
758 			window_pane_stack_remove(&w->last_panes, w->active);
759 			w->active->flags |= PANE_CHANGED;
760 			notify_window("window-pane-changed", w);
761 			window_update_focus(w);
762 		}
763 	}
764 }
765 
766 void
767 window_remove_pane(struct window *w, struct window_pane *wp)
768 {
769 	window_lost_pane(w, wp);
770 
771 	TAILQ_REMOVE(&w->panes, wp, entry);
772 	window_pane_destroy(wp);
773 }
774 
775 struct window_pane *
776 window_pane_at_index(struct window *w, u_int idx)
777 {
778 	struct window_pane	*wp;
779 	u_int			 n;
780 
781 	n = options_get_number(w->options, "pane-base-index");
782 	TAILQ_FOREACH(wp, &w->panes, entry) {
783 		if (n == idx)
784 			return (wp);
785 		n++;
786 	}
787 	return (NULL);
788 }
789 
790 struct window_pane *
791 window_pane_next_by_number(struct window *w, struct window_pane *wp, u_int n)
792 {
793 	for (; n > 0; n--) {
794 		if ((wp = TAILQ_NEXT(wp, entry)) == NULL)
795 			wp = TAILQ_FIRST(&w->panes);
796 	}
797 
798 	return (wp);
799 }
800 
801 struct window_pane *
802 window_pane_previous_by_number(struct window *w, struct window_pane *wp,
803     u_int n)
804 {
805 	for (; n > 0; n--) {
806 		if ((wp = TAILQ_PREV(wp, window_panes, entry)) == NULL)
807 			wp = TAILQ_LAST(&w->panes, window_panes);
808 	}
809 
810 	return (wp);
811 }
812 
813 int
814 window_pane_index(struct window_pane *wp, u_int *i)
815 {
816 	struct window_pane	*wq;
817 	struct window		*w = wp->window;
818 
819 	*i = options_get_number(w->options, "pane-base-index");
820 	TAILQ_FOREACH(wq, &w->panes, entry) {
821 		if (wp == wq) {
822 			return (0);
823 		}
824 		(*i)++;
825 	}
826 
827 	return (-1);
828 }
829 
830 u_int
831 window_count_panes(struct window *w)
832 {
833 	struct window_pane	*wp;
834 	u_int			 n;
835 
836 	n = 0;
837 	TAILQ_FOREACH(wp, &w->panes, entry)
838 		n++;
839 	return (n);
840 }
841 
842 void
843 window_destroy_panes(struct window *w)
844 {
845 	struct window_pane	*wp;
846 
847 	while (!TAILQ_EMPTY(&w->last_panes)) {
848 		wp = TAILQ_FIRST(&w->last_panes);
849 		window_pane_stack_remove(&w->last_panes, wp);
850 	}
851 
852 	while (!TAILQ_EMPTY(&w->panes)) {
853 		wp = TAILQ_FIRST(&w->panes);
854 		TAILQ_REMOVE(&w->panes, wp, entry);
855 		window_pane_destroy(wp);
856 	}
857 }
858 
859 const char *
860 window_printable_flags(struct winlink *wl, int escape)
861 {
862 	struct session	*s = wl->session;
863 	static char	 flags[32];
864 	int		 pos;
865 
866 	pos = 0;
867 	if (wl->flags & WINLINK_ACTIVITY) {
868 		flags[pos++] = '#';
869 		if (escape)
870 			flags[pos++] = '#';
871 	}
872 	if (wl->flags & WINLINK_BELL)
873 		flags[pos++] = '!';
874 	if (wl->flags & WINLINK_SILENCE)
875 		flags[pos++] = '~';
876 	if (wl == s->curw)
877 		flags[pos++] = '*';
878 	if (wl == TAILQ_FIRST(&s->lastw))
879 		flags[pos++] = '-';
880 	if (server_check_marked() && wl == marked_pane.wl)
881 		flags[pos++] = 'M';
882 	if (wl->window->flags & WINDOW_ZOOMED)
883 		flags[pos++] = 'Z';
884 	flags[pos] = '\0';
885 	return (flags);
886 }
887 
888 struct window_pane *
889 window_pane_find_by_id_str(const char *s)
890 {
891 	const char	*errstr;
892 	u_int		 id;
893 
894 	if (*s != '%')
895 		return (NULL);
896 
897 	id = strtonum(s + 1, 0, UINT_MAX, &errstr);
898 	if (errstr != NULL)
899 		return (NULL);
900 	return (window_pane_find_by_id(id));
901 }
902 
903 struct window_pane *
904 window_pane_find_by_id(u_int id)
905 {
906 	struct window_pane	wp;
907 
908 	wp.id = id;
909 	return (RB_FIND(window_pane_tree, &all_window_panes, &wp));
910 }
911 
912 static struct window_pane *
913 window_pane_create(struct window *w, u_int sx, u_int sy, u_int hlimit)
914 {
915 	struct window_pane	*wp;
916 	char			 host[HOST_NAME_MAX + 1];
917 
918 	wp = xcalloc(1, sizeof *wp);
919 	wp->window = w;
920 	wp->options = options_create(w->options);
921 	wp->flags = PANE_STYLECHANGED;
922 
923 	wp->id = next_window_pane_id++;
924 	RB_INSERT(window_pane_tree, &all_window_panes, wp);
925 
926 	wp->fd = -1;
927 
928 	TAILQ_INIT(&wp->modes);
929 
930 	TAILQ_INIT (&wp->resize_queue);
931 
932 	wp->sx = sx;
933 	wp->sy = sy;
934 
935 	wp->pipe_fd = -1;
936 
937 	colour_palette_init(&wp->palette);
938 	colour_palette_from_option(&wp->palette, wp->options);
939 
940 	screen_init(&wp->base, sx, sy, hlimit);
941 	wp->screen = &wp->base;
942 	window_pane_default_cursor(wp);
943 
944 	screen_init(&wp->status_screen, 1, 1, 0);
945 
946 	if (gethostname(host, sizeof host) == 0)
947 		screen_set_title(&wp->base, host);
948 
949 	return (wp);
950 }
951 
952 static void
953 window_pane_destroy(struct window_pane *wp)
954 {
955 	struct window_pane_resize	*r;
956 	struct window_pane_resize	*r1;
957 
958 	window_pane_reset_mode_all(wp);
959 	free(wp->searchstr);
960 
961 	if (wp->fd != -1) {
962 		bufferevent_free(wp->event);
963 		close(wp->fd);
964 	}
965 	if (wp->ictx != NULL)
966 		input_free(wp->ictx);
967 
968 	screen_free(&wp->status_screen);
969 
970 	screen_free(&wp->base);
971 
972 	if (wp->pipe_fd != -1) {
973 		bufferevent_free(wp->pipe_event);
974 		close(wp->pipe_fd);
975 	}
976 
977 	if (event_initialized(&wp->resize_timer))
978 		event_del(&wp->resize_timer);
979 	TAILQ_FOREACH_SAFE(r, &wp->resize_queue, entry, r1) {
980 		TAILQ_REMOVE(&wp->resize_queue, r, entry);
981 		free(r);
982 	}
983 
984 	RB_REMOVE(window_pane_tree, &all_window_panes, wp);
985 
986 	options_free(wp->options);
987 	free((void *)wp->cwd);
988 	free(wp->shell);
989 	cmd_free_argv(wp->argc, wp->argv);
990 	colour_palette_free(&wp->palette);
991 	free(wp);
992 }
993 
994 static void
995 window_pane_read_callback(__unused struct bufferevent *bufev, void *data)
996 {
997 	struct window_pane		*wp = data;
998 	struct evbuffer			*evb = wp->event->input;
999 	struct window_pane_offset	*wpo = &wp->pipe_offset;
1000 	size_t				 size = EVBUFFER_LENGTH(evb);
1001 	char				*new_data;
1002 	size_t				 new_size;
1003 	struct client			*c;
1004 
1005 	if (wp->pipe_fd != -1) {
1006 		new_data = window_pane_get_new_data(wp, wpo, &new_size);
1007 		if (new_size > 0) {
1008 			bufferevent_write(wp->pipe_event, new_data, new_size);
1009 			window_pane_update_used_data(wp, wpo, new_size);
1010 		}
1011 	}
1012 
1013 	log_debug("%%%u has %zu bytes", wp->id, size);
1014 	TAILQ_FOREACH(c, &clients, entry) {
1015 		if (c->session != NULL && (c->flags & CLIENT_CONTROL))
1016 			control_write_output(c, wp);
1017 	}
1018 	input_parse_pane(wp);
1019 	bufferevent_disable(wp->event, EV_READ);
1020 }
1021 
1022 static void
1023 window_pane_error_callback(__unused struct bufferevent *bufev,
1024     __unused short what, void *data)
1025 {
1026 	struct window_pane *wp = data;
1027 
1028 	log_debug("%%%u error", wp->id);
1029 	wp->flags |= PANE_EXITED;
1030 
1031 	if (window_pane_destroy_ready(wp))
1032 		server_destroy_pane(wp, 1);
1033 }
1034 
1035 void
1036 window_pane_set_event(struct window_pane *wp)
1037 {
1038 	setblocking(wp->fd, 0);
1039 
1040 	wp->event = bufferevent_new(wp->fd, window_pane_read_callback,
1041 	    NULL, window_pane_error_callback, wp);
1042 	if (wp->event == NULL)
1043 		fatalx("out of memory");
1044 	wp->ictx = input_init(wp, wp->event, &wp->palette);
1045 
1046 	bufferevent_enable(wp->event, EV_READ|EV_WRITE);
1047 }
1048 
1049 void
1050 window_pane_resize(struct window_pane *wp, u_int sx, u_int sy)
1051 {
1052 	struct window_mode_entry	*wme;
1053 	struct window_pane_resize	*r;
1054 
1055 	if (sx == wp->sx && sy == wp->sy)
1056 		return;
1057 
1058 	r = xmalloc(sizeof *r);
1059 	r->sx = sx;
1060 	r->sy = sy;
1061 	r->osx = wp->sx;
1062 	r->osy = wp->sy;
1063 	TAILQ_INSERT_TAIL (&wp->resize_queue, r, entry);
1064 
1065 	wp->sx = sx;
1066 	wp->sy = sy;
1067 
1068 	log_debug("%s: %%%u resize %ux%u", __func__, wp->id, sx, sy);
1069 	screen_resize(&wp->base, sx, sy, wp->base.saved_grid == NULL);
1070 
1071 	wme = TAILQ_FIRST(&wp->modes);
1072 	if (wme != NULL && wme->mode->resize != NULL)
1073 		wme->mode->resize(wme, sx, sy);
1074 }
1075 
1076 int
1077 window_pane_set_mode(struct window_pane *wp, struct window_pane *swp,
1078     const struct window_mode *mode, struct cmd_find_state *fs,
1079     struct args *args)
1080 {
1081 	struct window_mode_entry	*wme;
1082 
1083 	if (!TAILQ_EMPTY(&wp->modes) && TAILQ_FIRST(&wp->modes)->mode == mode)
1084 		return (1);
1085 
1086 	TAILQ_FOREACH(wme, &wp->modes, entry) {
1087 		if (wme->mode == mode)
1088 			break;
1089 	}
1090 	if (wme != NULL) {
1091 		TAILQ_REMOVE(&wp->modes, wme, entry);
1092 		TAILQ_INSERT_HEAD(&wp->modes, wme, entry);
1093 	} else {
1094 		wme = xcalloc(1, sizeof *wme);
1095 		wme->wp = wp;
1096 		wme->swp = swp;
1097 		wme->mode = mode;
1098 		wme->prefix = 1;
1099 		TAILQ_INSERT_HEAD(&wp->modes, wme, entry);
1100 		wme->screen = wme->mode->init(wme, fs, args);
1101 	}
1102 
1103 	wp->screen = wme->screen;
1104 	wp->flags |= (PANE_REDRAW|PANE_CHANGED);
1105 
1106 	server_redraw_window_borders(wp->window);
1107 	server_status_window(wp->window);
1108 	notify_pane("pane-mode-changed", wp);
1109 
1110 	return (0);
1111 }
1112 
1113 void
1114 window_pane_reset_mode(struct window_pane *wp)
1115 {
1116 	struct window_mode_entry	*wme, *next;
1117 
1118 	if (TAILQ_EMPTY(&wp->modes))
1119 		return;
1120 
1121 	wme = TAILQ_FIRST(&wp->modes);
1122 	TAILQ_REMOVE(&wp->modes, wme, entry);
1123 	wme->mode->free(wme);
1124 	free(wme);
1125 
1126 	next = TAILQ_FIRST(&wp->modes);
1127 	if (next == NULL) {
1128 		wp->flags &= ~PANE_UNSEENCHANGES;
1129 		log_debug("%s: no next mode", __func__);
1130 		wp->screen = &wp->base;
1131 	} else {
1132 		log_debug("%s: next mode is %s", __func__, next->mode->name);
1133 		wp->screen = next->screen;
1134 		if (next->mode->resize != NULL)
1135 			next->mode->resize(next, wp->sx, wp->sy);
1136 	}
1137 	wp->flags |= (PANE_REDRAW|PANE_CHANGED);
1138 
1139 	server_redraw_window_borders(wp->window);
1140 	server_status_window(wp->window);
1141 	notify_pane("pane-mode-changed", wp);
1142 }
1143 
1144 void
1145 window_pane_reset_mode_all(struct window_pane *wp)
1146 {
1147 	while (!TAILQ_EMPTY(&wp->modes))
1148 		window_pane_reset_mode(wp);
1149 }
1150 
1151 static void
1152 window_pane_copy_key(struct window_pane *wp, key_code key)
1153 {
1154  	struct window_pane	*loop;
1155 
1156 	TAILQ_FOREACH(loop, &wp->window->panes, entry) {
1157 		if (loop != wp &&
1158 		    TAILQ_EMPTY(&loop->modes) &&
1159 		    loop->fd != -1 &&
1160 		    (~loop->flags & PANE_INPUTOFF) &&
1161 		    window_pane_visible(loop) &&
1162 		    options_get_number(loop->options, "synchronize-panes"))
1163 			input_key_pane(loop, key, NULL);
1164 	}
1165 }
1166 
1167 int
1168 window_pane_key(struct window_pane *wp, struct client *c, struct session *s,
1169     struct winlink *wl, key_code key, struct mouse_event *m)
1170 {
1171 	struct window_mode_entry	*wme;
1172 
1173 	if (KEYC_IS_MOUSE(key) && m == NULL)
1174 		return (-1);
1175 
1176 	wme = TAILQ_FIRST(&wp->modes);
1177 	if (wme != NULL) {
1178 		if (wme->mode->key != NULL && c != NULL) {
1179 			key &= ~KEYC_MASK_FLAGS;
1180 			wme->mode->key(wme, c, s, wl, key, m);
1181 		}
1182 		return (0);
1183 	}
1184 
1185 	if (wp->fd == -1 || wp->flags & PANE_INPUTOFF)
1186 		return (0);
1187 
1188 	if (input_key_pane(wp, key, m) != 0)
1189 		return (-1);
1190 
1191 	if (KEYC_IS_MOUSE(key))
1192 		return (0);
1193 	if (options_get_number(wp->options, "synchronize-panes"))
1194 		window_pane_copy_key(wp, key);
1195 	return (0);
1196 }
1197 
1198 int
1199 window_pane_visible(struct window_pane *wp)
1200 {
1201 	if (~wp->window->flags & WINDOW_ZOOMED)
1202 		return (1);
1203 	return (wp == wp->window->active);
1204 }
1205 
1206 u_int
1207 window_pane_search(struct window_pane *wp, const char *term, int regex,
1208     int ignore)
1209 {
1210 	struct screen	*s = &wp->base;
1211 	regex_t		 r;
1212 	char		*new = NULL, *line;
1213 	u_int		 i;
1214 	int		 flags = 0, found;
1215 	size_t		 n;
1216 
1217 	if (!regex) {
1218 		if (ignore)
1219 			flags |= FNM_CASEFOLD;
1220 		xasprintf(&new, "*%s*", term);
1221 	} else {
1222 		if (ignore)
1223 			flags |= REG_ICASE;
1224 		if (regcomp(&r, term, flags|REG_EXTENDED) != 0)
1225 			return (0);
1226 	}
1227 
1228 	for (i = 0; i < screen_size_y(s); i++) {
1229 		line = grid_view_string_cells(s->grid, 0, i, screen_size_x(s));
1230 		for (n = strlen(line); n > 0; n--) {
1231 			if (!isspace((u_char)line[n - 1]))
1232 				break;
1233 			line[n - 1] = '\0';
1234 		}
1235 		log_debug("%s: %s", __func__, line);
1236 		if (!regex)
1237 			found = (fnmatch(new, line, flags) == 0);
1238 		else
1239 			found = (regexec(&r, line, 0, NULL, 0) == 0);
1240 		free(line);
1241 		if (found)
1242 			break;
1243 	}
1244 	if (!regex)
1245 		free(new);
1246 	else
1247 		regfree(&r);
1248 
1249 	if (i == screen_size_y(s))
1250 		return (0);
1251 	return (i + 1);
1252 }
1253 
1254 /* Get MRU pane from a list. */
1255 static struct window_pane *
1256 window_pane_choose_best(struct window_pane **list, u_int size)
1257 {
1258 	struct window_pane	*next, *best;
1259 	u_int			 i;
1260 
1261 	if (size == 0)
1262 		return (NULL);
1263 
1264 	best = list[0];
1265 	for (i = 1; i < size; i++) {
1266 		next = list[i];
1267 		if (next->active_point > best->active_point)
1268 			best = next;
1269 	}
1270 	return (best);
1271 }
1272 
1273 /*
1274  * Find the pane directly above another. We build a list of those adjacent to
1275  * top edge and then choose the best.
1276  */
1277 struct window_pane *
1278 window_pane_find_up(struct window_pane *wp)
1279 {
1280 	struct window		*w;
1281 	struct window_pane	*next, *best, **list;
1282 	u_int			 edge, left, right, end, size;
1283 	int			 status, found;
1284 
1285 	if (wp == NULL)
1286 		return (NULL);
1287 	w = wp->window;
1288 	status = options_get_number(w->options, "pane-border-status");
1289 
1290 	list = NULL;
1291 	size = 0;
1292 
1293 	edge = wp->yoff;
1294 	if (status == PANE_STATUS_TOP) {
1295 		if (edge == 1)
1296 			edge = w->sy + 1;
1297 	} else if (status == PANE_STATUS_BOTTOM) {
1298 		if (edge == 0)
1299 			edge = w->sy;
1300 	} else {
1301 		if (edge == 0)
1302 			edge = w->sy + 1;
1303 	}
1304 
1305 	left = wp->xoff;
1306 	right = wp->xoff + wp->sx;
1307 
1308 	TAILQ_FOREACH(next, &w->panes, entry) {
1309 		if (next == wp)
1310 			continue;
1311 		if (next->yoff + next->sy + 1 != edge)
1312 			continue;
1313 		end = next->xoff + next->sx - 1;
1314 
1315 		found = 0;
1316 		if (next->xoff < left && end > right)
1317 			found = 1;
1318 		else if (next->xoff >= left && next->xoff <= right)
1319 			found = 1;
1320 		else if (end >= left && end <= right)
1321 			found = 1;
1322 		if (!found)
1323 			continue;
1324 		list = xreallocarray(list, size + 1, sizeof *list);
1325 		list[size++] = next;
1326 	}
1327 
1328 	best = window_pane_choose_best(list, size);
1329 	free(list);
1330 	return (best);
1331 }
1332 
1333 /* Find the pane directly below another. */
1334 struct window_pane *
1335 window_pane_find_down(struct window_pane *wp)
1336 {
1337 	struct window		*w;
1338 	struct window_pane	*next, *best, **list;
1339 	u_int			 edge, left, right, end, size;
1340 	int			 status, found;
1341 
1342 	if (wp == NULL)
1343 		return (NULL);
1344 	w = wp->window;
1345 	status = options_get_number(w->options, "pane-border-status");
1346 
1347 	list = NULL;
1348 	size = 0;
1349 
1350 	edge = wp->yoff + wp->sy + 1;
1351 	if (status == PANE_STATUS_TOP) {
1352 		if (edge >= w->sy)
1353 			edge = 1;
1354 	} else if (status == PANE_STATUS_BOTTOM) {
1355 		if (edge >= w->sy - 1)
1356 			edge = 0;
1357 	} else {
1358 		if (edge >= w->sy)
1359 			edge = 0;
1360 	}
1361 
1362 	left = wp->xoff;
1363 	right = wp->xoff + wp->sx;
1364 
1365 	TAILQ_FOREACH(next, &w->panes, entry) {
1366 		if (next == wp)
1367 			continue;
1368 		if (next->yoff != edge)
1369 			continue;
1370 		end = next->xoff + next->sx - 1;
1371 
1372 		found = 0;
1373 		if (next->xoff < left && end > right)
1374 			found = 1;
1375 		else if (next->xoff >= left && next->xoff <= right)
1376 			found = 1;
1377 		else if (end >= left && end <= right)
1378 			found = 1;
1379 		if (!found)
1380 			continue;
1381 		list = xreallocarray(list, size + 1, sizeof *list);
1382 		list[size++] = next;
1383 	}
1384 
1385 	best = window_pane_choose_best(list, size);
1386 	free(list);
1387 	return (best);
1388 }
1389 
1390 /* Find the pane directly to the left of another. */
1391 struct window_pane *
1392 window_pane_find_left(struct window_pane *wp)
1393 {
1394 	struct window		*w;
1395 	struct window_pane	*next, *best, **list;
1396 	u_int			 edge, top, bottom, end, size;
1397 	int			 found;
1398 
1399 	if (wp == NULL)
1400 		return (NULL);
1401 	w = wp->window;
1402 
1403 	list = NULL;
1404 	size = 0;
1405 
1406 	edge = wp->xoff;
1407 	if (edge == 0)
1408 		edge = w->sx + 1;
1409 
1410 	top = wp->yoff;
1411 	bottom = wp->yoff + wp->sy;
1412 
1413 	TAILQ_FOREACH(next, &w->panes, entry) {
1414 		if (next == wp)
1415 			continue;
1416 		if (next->xoff + next->sx + 1 != edge)
1417 			continue;
1418 		end = next->yoff + next->sy - 1;
1419 
1420 		found = 0;
1421 		if (next->yoff < top && end > bottom)
1422 			found = 1;
1423 		else if (next->yoff >= top && next->yoff <= bottom)
1424 			found = 1;
1425 		else if (end >= top && end <= bottom)
1426 			found = 1;
1427 		if (!found)
1428 			continue;
1429 		list = xreallocarray(list, size + 1, sizeof *list);
1430 		list[size++] = next;
1431 	}
1432 
1433 	best = window_pane_choose_best(list, size);
1434 	free(list);
1435 	return (best);
1436 }
1437 
1438 /* Find the pane directly to the right of another. */
1439 struct window_pane *
1440 window_pane_find_right(struct window_pane *wp)
1441 {
1442 	struct window		*w;
1443 	struct window_pane	*next, *best, **list;
1444 	u_int			 edge, top, bottom, end, size;
1445 	int			 found;
1446 
1447 	if (wp == NULL)
1448 		return (NULL);
1449 	w = wp->window;
1450 
1451 	list = NULL;
1452 	size = 0;
1453 
1454 	edge = wp->xoff + wp->sx + 1;
1455 	if (edge >= w->sx)
1456 		edge = 0;
1457 
1458 	top = wp->yoff;
1459 	bottom = wp->yoff + wp->sy;
1460 
1461 	TAILQ_FOREACH(next, &w->panes, entry) {
1462 		if (next == wp)
1463 			continue;
1464 		if (next->xoff != edge)
1465 			continue;
1466 		end = next->yoff + next->sy - 1;
1467 
1468 		found = 0;
1469 		if (next->yoff < top && end > bottom)
1470 			found = 1;
1471 		else if (next->yoff >= top && next->yoff <= bottom)
1472 			found = 1;
1473 		else if (end >= top && end <= bottom)
1474 			found = 1;
1475 		if (!found)
1476 			continue;
1477 		list = xreallocarray(list, size + 1, sizeof *list);
1478 		list[size++] = next;
1479 	}
1480 
1481 	best = window_pane_choose_best(list, size);
1482 	free(list);
1483 	return (best);
1484 }
1485 
1486 void
1487 window_pane_stack_push(struct window_panes *stack, struct window_pane *wp)
1488 {
1489 	if (wp != NULL) {
1490 		window_pane_stack_remove(stack, wp);
1491 		TAILQ_INSERT_HEAD(stack, wp, sentry);
1492 		wp->flags |= PANE_VISITED;
1493 	}
1494 }
1495 
1496 void
1497 window_pane_stack_remove(struct window_panes *stack, struct window_pane *wp)
1498 {
1499 	if (wp != NULL && (wp->flags & PANE_VISITED)) {
1500 		TAILQ_REMOVE(stack, wp, sentry);
1501 		wp->flags &= ~PANE_VISITED;
1502 	}
1503 }
1504 
1505 /* Clear alert flags for a winlink */
1506 void
1507 winlink_clear_flags(struct winlink *wl)
1508 {
1509 	struct winlink	*loop;
1510 
1511 	wl->window->flags &= ~WINDOW_ALERTFLAGS;
1512 	TAILQ_FOREACH(loop, &wl->window->winlinks, wentry) {
1513 		if ((loop->flags & WINLINK_ALERTFLAGS) != 0) {
1514 			loop->flags &= ~WINLINK_ALERTFLAGS;
1515 			server_status_session(loop->session);
1516 		}
1517 	}
1518 }
1519 
1520 /* Shuffle window indexes up. */
1521 int
1522 winlink_shuffle_up(struct session *s, struct winlink *wl, int before)
1523 {
1524 	int	 idx, last;
1525 
1526 	if (wl == NULL)
1527 		return (-1);
1528 	if (before)
1529 		idx = wl->idx;
1530 	else
1531 		idx = wl->idx + 1;
1532 
1533 	/* Find the next free index. */
1534 	for (last = idx; last < INT_MAX; last++) {
1535 		if (winlink_find_by_index(&s->windows, last) == NULL)
1536 			break;
1537 	}
1538 	if (last == INT_MAX)
1539 		return (-1);
1540 
1541 	/* Move everything from last - 1 to idx up a bit. */
1542 	for (; last > idx; last--) {
1543 		wl = winlink_find_by_index(&s->windows, last - 1);
1544 		RB_REMOVE(winlinks, &s->windows, wl);
1545 		wl->idx++;
1546 		RB_INSERT(winlinks, &s->windows, wl);
1547 	}
1548 
1549 	return (idx);
1550 }
1551 
1552 static void
1553 window_pane_input_callback(struct client *c, __unused const char *path,
1554     int error, int closed, struct evbuffer *buffer, void *data)
1555 {
1556 	struct window_pane_input_data	*cdata = data;
1557 	struct window_pane		*wp;
1558 	u_char				*buf = EVBUFFER_DATA(buffer);
1559 	size_t				 len = EVBUFFER_LENGTH(buffer);
1560 
1561 	wp = window_pane_find_by_id(cdata->wp);
1562 	if (cdata->file != NULL && (wp == NULL || c->flags & CLIENT_DEAD)) {
1563 		if (wp == NULL) {
1564 			c->retval = 1;
1565 			c->flags |= CLIENT_EXIT;
1566 		}
1567 		file_cancel(cdata->file);
1568 	} else if (cdata->file == NULL || closed || error != 0) {
1569 		cmdq_continue(cdata->item);
1570 		server_client_unref(c);
1571 		free(cdata);
1572 	} else
1573 		input_parse_buffer(wp, buf, len);
1574 	evbuffer_drain(buffer, len);
1575 }
1576 
1577 int
1578 window_pane_start_input(struct window_pane *wp, struct cmdq_item *item,
1579     char **cause)
1580 {
1581 	struct client			*c = cmdq_get_client(item);
1582 	struct window_pane_input_data	*cdata;
1583 
1584 	if (~wp->flags & PANE_EMPTY) {
1585 		*cause = xstrdup("pane is not empty");
1586 		return (-1);
1587 	}
1588 	if (c->flags & (CLIENT_DEAD|CLIENT_EXITED))
1589 		return (1);
1590 	if (c->session != NULL)
1591 		return (1);
1592 
1593 	cdata = xmalloc(sizeof *cdata);
1594 	cdata->item = item;
1595 	cdata->wp = wp->id;
1596 	cdata->file = file_read(c, "-", window_pane_input_callback, cdata);
1597 	c->references++;
1598 
1599 	return (0);
1600 }
1601 
1602 void *
1603 window_pane_get_new_data(struct window_pane *wp,
1604     struct window_pane_offset *wpo, size_t *size)
1605 {
1606 	size_t	used = wpo->used - wp->base_offset;
1607 
1608 	*size = EVBUFFER_LENGTH(wp->event->input) - used;
1609 	return (EVBUFFER_DATA(wp->event->input) + used);
1610 }
1611 
1612 void
1613 window_pane_update_used_data(struct window_pane *wp,
1614     struct window_pane_offset *wpo, size_t size)
1615 {
1616 	size_t	used = wpo->used - wp->base_offset;
1617 
1618 	if (size > EVBUFFER_LENGTH(wp->event->input) - used)
1619 		size = EVBUFFER_LENGTH(wp->event->input) - used;
1620 	wpo->used += size;
1621 }
1622 
1623 void
1624 window_set_fill_character(struct window *w)
1625 {
1626 	const char		*value;
1627 	struct utf8_data	*ud;
1628 
1629 	free(w->fill_character);
1630 	w->fill_character = NULL;
1631 
1632 	value = options_get_string(w->options, "fill-character");
1633 	if (*value != '\0' && utf8_isvalid(value)) {
1634 		ud = utf8_fromcstr(value);
1635 		if (ud != NULL && ud[0].width == 1)
1636 			w->fill_character = ud;
1637 	}
1638 }
1639 
1640 void
1641 window_pane_default_cursor(struct window_pane *wp)
1642 {
1643 	struct screen	*s = wp->screen;
1644 	int		 c;
1645 
1646 	c = options_get_number(wp->options, "cursor-colour");
1647 	s->default_ccolour = c;
1648 
1649 	c = options_get_number(wp->options, "cursor-style");
1650 	s->default_mode = 0;
1651 	screen_set_cursor_style(c, &s->default_cstyle, &s->default_mode);
1652 }
1653