1/* $OpenBSD$ */
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/time.h>
21
22#include <string.h>
23#include <stdlib.h>
24#include <unistd.h>
25#include <time.h>
26
27#include "tmux.h"
28
29struct sessions		sessions;
30u_int			next_session_id;
31struct session_groups	session_groups = RB_INITIALIZER(&session_groups);
32
33static void	session_free(int, short, void *);
34
35static void	session_lock_timer(int, short, void *);
36
37static struct winlink *session_next_alert(struct winlink *);
38static struct winlink *session_previous_alert(struct winlink *);
39
40static void	session_group_remove(struct session *);
41static void	session_group_synchronize1(struct session *, struct session *);
42
43int
44session_cmp(struct session *s1, struct session *s2)
45{
46	return (strcmp(s1->name, s2->name));
47}
48RB_GENERATE(sessions, session, entry, session_cmp);
49
50static int
51session_group_cmp(struct session_group *s1, struct session_group *s2)
52{
53	return (strcmp(s1->name, s2->name));
54}
55RB_GENERATE_STATIC(session_groups, session_group, entry, session_group_cmp);
56
57/*
58 * Find if session is still alive. This is true if it is still on the global
59 * sessions list.
60 */
61int
62session_alive(struct session *s)
63{
64	struct session *s_loop;
65
66	RB_FOREACH(s_loop, sessions, &sessions) {
67		if (s_loop == s)
68			return (1);
69	}
70	return (0);
71}
72
73/* Find session by name. */
74struct session *
75session_find(const char *name)
76{
77	struct session	s;
78
79	s.name = __UNCONST(name);
80	return (RB_FIND(sessions, &sessions, &s));
81}
82
83/* Find session by id parsed from a string. */
84struct session *
85session_find_by_id_str(const char *s)
86{
87	const char	*errstr;
88	u_int		 id;
89
90	if (*s != '$')
91		return (NULL);
92
93	id = strtonum(s + 1, 0, UINT_MAX, &errstr);
94	if (errstr != NULL)
95		return (NULL);
96	return (session_find_by_id(id));
97}
98
99/* Find session by id. */
100struct session *
101session_find_by_id(u_int id)
102{
103	struct session	*s;
104
105	RB_FOREACH(s, sessions, &sessions) {
106		if (s->id == id)
107			return (s);
108	}
109	return (NULL);
110}
111
112/* Create a new session. */
113struct session *
114session_create(const char *prefix, const char *name, const char *cwd,
115    struct environ *env, struct options *oo, struct termios *tio)
116{
117	struct session	*s;
118
119	s = xcalloc(1, sizeof *s);
120	s->references = 1;
121	s->flags = 0;
122
123	s->cwd = xstrdup(cwd);
124
125	TAILQ_INIT(&s->lastw);
126	RB_INIT(&s->windows);
127
128	s->environ = env;
129	s->options = oo;
130
131	status_update_cache(s);
132
133	s->tio = NULL;
134	if (tio != NULL) {
135		s->tio = xmalloc(sizeof *s->tio);
136		memcpy(s->tio, tio, sizeof *s->tio);
137	}
138
139	if (name != NULL) {
140		s->name = xstrdup(name);
141		s->id = next_session_id++;
142	} else {
143		do {
144			s->id = next_session_id++;
145			free(s->name);
146			if (prefix != NULL)
147				xasprintf(&s->name, "%s-%u", prefix, s->id);
148			else
149				xasprintf(&s->name, "%u", s->id);
150		} while (RB_FIND(sessions, &sessions, s) != NULL);
151	}
152	RB_INSERT(sessions, &sessions, s);
153
154	log_debug("new session %s $%u", s->name, s->id);
155
156	if (gettimeofday(&s->creation_time, NULL) != 0)
157		fatal("gettimeofday failed");
158	session_update_activity(s, &s->creation_time);
159
160	return (s);
161}
162
163/* Add a reference to a session. */
164void
165session_add_ref(struct session *s, const char *from)
166{
167	s->references++;
168	log_debug("%s: %s %s, now %d", __func__, s->name, from, s->references);
169}
170
171/* Remove a reference from a session. */
172void
173session_remove_ref(struct session *s, const char *from)
174{
175	s->references--;
176	log_debug("%s: %s %s, now %d", __func__, s->name, from, s->references);
177
178	if (s->references == 0)
179		event_once(-1, EV_TIMEOUT, session_free, s, NULL);
180}
181
182/* Free session. */
183static void
184session_free(__unused int fd, __unused short events, void *arg)
185{
186	struct session	*s = arg;
187
188	log_debug("session %s freed (%d references)", s->name, s->references);
189
190	if (s->references == 0) {
191		environ_free(s->environ);
192		options_free(s->options);
193
194		free(s->name);
195		free(s);
196	}
197}
198
199/* Destroy a session. */
200void
201session_destroy(struct session *s, int notify, const char *from)
202{
203	struct winlink	*wl;
204
205	log_debug("session %s destroyed (%s)", s->name, from);
206
207	if (s->curw == NULL)
208		return;
209	s->curw = NULL;
210
211	RB_REMOVE(sessions, &sessions, s);
212	if (notify)
213		notify_session("session-closed", s);
214
215	free(s->tio);
216
217	if (event_initialized(&s->lock_timer))
218		event_del(&s->lock_timer);
219
220	session_group_remove(s);
221
222	while (!TAILQ_EMPTY(&s->lastw))
223		winlink_stack_remove(&s->lastw, TAILQ_FIRST(&s->lastw));
224	while (!RB_EMPTY(&s->windows)) {
225		wl = RB_ROOT(&s->windows);
226		notify_session_window("window-unlinked", s, wl->window);
227		winlink_remove(&s->windows, wl);
228	}
229
230	free(__UNCONST(s->cwd));
231
232	session_remove_ref(s, __func__);
233}
234
235/* Sanitize session name. */
236char *
237session_check_name(const char *name)
238{
239	char	*copy, *cp, *new_name;
240
241	if (*name == '\0')
242		return (NULL);
243	copy = xstrdup(name);
244	for (cp = copy; *cp != '\0'; cp++) {
245		if (*cp == ':' || *cp == '.')
246			*cp = '_';
247	}
248	utf8_stravis(&new_name, copy, VIS_OCTAL|VIS_CSTYLE|VIS_TAB|VIS_NL);
249	free(copy);
250	return (new_name);
251}
252
253/* Lock session if it has timed out. */
254static void
255session_lock_timer(__unused int fd, __unused short events, void *arg)
256{
257	struct session	*s = arg;
258
259	if (s->attached == 0)
260		return;
261
262	log_debug("session %s locked, activity time %lld", s->name,
263	    (long long)s->activity_time.tv_sec);
264
265	server_lock_session(s);
266	recalculate_sizes();
267}
268
269/* Update activity time. */
270void
271session_update_activity(struct session *s, struct timeval *from)
272{
273	struct timeval	*last = &s->last_activity_time;
274	struct timeval	 tv;
275
276	memcpy(last, &s->activity_time, sizeof *last);
277	if (from == NULL)
278		gettimeofday(&s->activity_time, NULL);
279	else
280		memcpy(&s->activity_time, from, sizeof s->activity_time);
281
282	log_debug("session $%u %s activity %lld.%06d (last %lld.%06d)", s->id,
283	    s->name, (long long)s->activity_time.tv_sec,
284	    (int)s->activity_time.tv_usec, (long long)last->tv_sec,
285	    (int)last->tv_usec);
286
287	if (evtimer_initialized(&s->lock_timer))
288		evtimer_del(&s->lock_timer);
289	else
290		evtimer_set(&s->lock_timer, session_lock_timer, s);
291
292	if (s->attached != 0) {
293		timerclear(&tv);
294		tv.tv_sec = options_get_number(s->options, "lock-after-time");
295		if (tv.tv_sec != 0)
296			evtimer_add(&s->lock_timer, &tv);
297	}
298}
299
300/* Find the next usable session. */
301struct session *
302session_next_session(struct session *s)
303{
304	struct session *s2;
305
306	if (RB_EMPTY(&sessions) || !session_alive(s))
307		return (NULL);
308
309	s2 = RB_NEXT(sessions, &sessions, s);
310	if (s2 == NULL)
311		s2 = RB_MIN(sessions, &sessions);
312	if (s2 == s)
313		return (NULL);
314	return (s2);
315}
316
317/* Find the previous usable session. */
318struct session *
319session_previous_session(struct session *s)
320{
321	struct session *s2;
322
323	if (RB_EMPTY(&sessions) || !session_alive(s))
324		return (NULL);
325
326	s2 = RB_PREV(sessions, &sessions, s);
327	if (s2 == NULL)
328		s2 = RB_MAX(sessions, &sessions);
329	if (s2 == s)
330		return (NULL);
331	return (s2);
332}
333
334/* Attach a window to a session. */
335struct winlink *
336session_attach(struct session *s, struct window *w, int idx, char **cause)
337{
338	struct winlink	*wl;
339
340	if ((wl = winlink_add(&s->windows, idx)) == NULL) {
341		xasprintf(cause, "index in use: %d", idx);
342		return (NULL);
343	}
344	wl->session = s;
345	winlink_set_window(wl, w);
346	notify_session_window("window-linked", s, w);
347
348	session_group_synchronize_from(s);
349	return (wl);
350}
351
352/* Detach a window from a session. */
353int
354session_detach(struct session *s, struct winlink *wl)
355{
356	if (s->curw == wl &&
357	    session_last(s) != 0 &&
358	    session_previous(s, 0) != 0)
359		session_next(s, 0);
360
361	wl->flags &= ~WINLINK_ALERTFLAGS;
362	notify_session_window("window-unlinked", s, wl->window);
363	winlink_stack_remove(&s->lastw, wl);
364	winlink_remove(&s->windows, wl);
365
366	session_group_synchronize_from(s);
367
368	if (RB_EMPTY(&s->windows)) {
369		session_destroy(s, 1, __func__);
370		return (1);
371	}
372	return (0);
373}
374
375/* Return if session has window. */
376int
377session_has(struct session *s, struct window *w)
378{
379	struct winlink	*wl;
380
381	TAILQ_FOREACH(wl, &w->winlinks, wentry) {
382		if (wl->session == s)
383			return (1);
384	}
385	return (0);
386}
387
388/*
389 * Return 1 if a window is linked outside this session (not including session
390 * groups). The window must be in this session!
391 */
392int
393session_is_linked(struct session *s, struct window *w)
394{
395	struct session_group	*sg;
396
397	if ((sg = session_group_contains(s)) != NULL)
398		return (w->references != session_group_count(sg));
399	return (w->references != 1);
400}
401
402static struct winlink *
403session_next_alert(struct winlink *wl)
404{
405	while (wl != NULL) {
406		if (wl->flags & WINLINK_ALERTFLAGS)
407			break;
408		wl = winlink_next(wl);
409	}
410	return (wl);
411}
412
413/* Move session to next window. */
414int
415session_next(struct session *s, int alert)
416{
417	struct winlink	*wl;
418
419	if (s->curw == NULL)
420		return (-1);
421
422	wl = winlink_next(s->curw);
423	if (alert)
424		wl = session_next_alert(wl);
425	if (wl == NULL) {
426		wl = RB_MIN(winlinks, &s->windows);
427		if (alert && ((wl = session_next_alert(wl)) == NULL))
428			return (-1);
429	}
430	return (session_set_current(s, wl));
431}
432
433static struct winlink *
434session_previous_alert(struct winlink *wl)
435{
436	while (wl != NULL) {
437		if (wl->flags & WINLINK_ALERTFLAGS)
438			break;
439		wl = winlink_previous(wl);
440	}
441	return (wl);
442}
443
444/* Move session to previous window. */
445int
446session_previous(struct session *s, int alert)
447{
448	struct winlink	*wl;
449
450	if (s->curw == NULL)
451		return (-1);
452
453	wl = winlink_previous(s->curw);
454	if (alert)
455		wl = session_previous_alert(wl);
456	if (wl == NULL) {
457		wl = RB_MAX(winlinks, &s->windows);
458		if (alert && (wl = session_previous_alert(wl)) == NULL)
459			return (-1);
460	}
461	return (session_set_current(s, wl));
462}
463
464/* Move session to specific window. */
465int
466session_select(struct session *s, int idx)
467{
468	struct winlink	*wl;
469
470	wl = winlink_find_by_index(&s->windows, idx);
471	return (session_set_current(s, wl));
472}
473
474/* Move session to last used window. */
475int
476session_last(struct session *s)
477{
478	struct winlink	*wl;
479
480	wl = TAILQ_FIRST(&s->lastw);
481	if (wl == NULL)
482		return (-1);
483	if (wl == s->curw)
484		return (1);
485
486	return (session_set_current(s, wl));
487}
488
489/* Set current winlink to wl .*/
490int
491session_set_current(struct session *s, struct winlink *wl)
492{
493	struct winlink	*old = s->curw;
494
495	if (wl == NULL)
496		return (-1);
497	if (wl == s->curw)
498		return (1);
499
500	winlink_stack_remove(&s->lastw, wl);
501	winlink_stack_push(&s->lastw, s->curw);
502	s->curw = wl;
503	if (options_get_number(global_options, "focus-events")) {
504		if (old != NULL)
505			window_update_focus(old->window);
506		window_update_focus(wl->window);
507	}
508	winlink_clear_flags(wl);
509	window_update_activity(wl->window);
510	tty_update_window_offset(wl->window);
511	notify_session("session-window-changed", s);
512	return (0);
513}
514
515/* Find the session group containing a session. */
516struct session_group *
517session_group_contains(struct session *target)
518{
519	struct session_group	*sg;
520	struct session		*s;
521
522	RB_FOREACH(sg, session_groups, &session_groups) {
523		TAILQ_FOREACH(s, &sg->sessions, gentry) {
524			if (s == target)
525				return (sg);
526		}
527	}
528	return (NULL);
529}
530
531/* Find session group by name. */
532struct session_group *
533session_group_find(const char *name)
534{
535	struct session_group	sg;
536
537	sg.name = name;
538	return (RB_FIND(session_groups, &session_groups, &sg));
539}
540
541/* Create a new session group. */
542struct session_group *
543session_group_new(const char *name)
544{
545	struct session_group	*sg;
546
547	if ((sg = session_group_find(name)) != NULL)
548		return (sg);
549
550	sg = xcalloc(1, sizeof *sg);
551	sg->name = xstrdup(name);
552	TAILQ_INIT(&sg->sessions);
553
554	RB_INSERT(session_groups, &session_groups, sg);
555	return (sg);
556}
557
558/* Add a session to a session group. */
559void
560session_group_add(struct session_group *sg, struct session *s)
561{
562	if (session_group_contains(s) == NULL)
563		TAILQ_INSERT_TAIL(&sg->sessions, s, gentry);
564}
565
566/* Remove a session from its group and destroy the group if empty. */
567static void
568session_group_remove(struct session *s)
569{
570	struct session_group	*sg;
571
572	if ((sg = session_group_contains(s)) == NULL)
573		return;
574	TAILQ_REMOVE(&sg->sessions, s, gentry);
575	if (TAILQ_EMPTY(&sg->sessions)) {
576		RB_REMOVE(session_groups, &session_groups, sg);
577		free(__UNCONST(sg->name));
578		free(sg);
579	}
580}
581
582/* Count number of sessions in session group. */
583u_int
584session_group_count(struct session_group *sg)
585{
586	struct session	*s;
587	u_int		 n;
588
589	n = 0;
590	TAILQ_FOREACH(s, &sg->sessions, gentry)
591		n++;
592	return (n);
593}
594
595/* Count number of clients attached to sessions in session group. */
596u_int
597session_group_attached_count(struct session_group *sg)
598{
599	struct session	*s;
600	u_int		 n;
601
602	n = 0;
603	TAILQ_FOREACH(s, &sg->sessions, gentry)
604		n += s->attached;
605	return (n);
606}
607
608/* Synchronize a session to its session group. */
609void
610session_group_synchronize_to(struct session *s)
611{
612	struct session_group	*sg;
613	struct session		*target;
614
615	if ((sg = session_group_contains(s)) == NULL)
616		return;
617
618	target = NULL;
619	TAILQ_FOREACH(target, &sg->sessions, gentry) {
620		if (target != s)
621			break;
622	}
623	if (target != NULL)
624		session_group_synchronize1(target, s);
625}
626
627/* Synchronize a session group to a session. */
628void
629session_group_synchronize_from(struct session *target)
630{
631	struct session_group	*sg;
632	struct session		*s;
633
634	if ((sg = session_group_contains(target)) == NULL)
635		return;
636
637	TAILQ_FOREACH(s, &sg->sessions, gentry) {
638		if (s != target)
639			session_group_synchronize1(target, s);
640	}
641}
642
643/*
644 * Synchronize a session with a target session. This means destroying all
645 * winlinks then recreating them, then updating the current window, last window
646 * stack and alerts.
647 */
648static void
649session_group_synchronize1(struct session *target, struct session *s)
650{
651	struct winlinks		 old_windows, *ww;
652	struct winlink_stack	 old_lastw;
653	struct winlink		*wl, *wl2;
654
655	/* Don't do anything if the session is empty (it'll be destroyed). */
656	ww = &target->windows;
657	if (RB_EMPTY(ww))
658		return;
659
660	/* If the current window has vanished, move to the next now. */
661	if (s->curw != NULL &&
662	    winlink_find_by_index(ww, s->curw->idx) == NULL &&
663	    session_last(s) != 0 && session_previous(s, 0) != 0)
664		session_next(s, 0);
665
666	/* Save the old pointer and reset it. */
667	memcpy(&old_windows, &s->windows, sizeof old_windows);
668	RB_INIT(&s->windows);
669
670	/* Link all the windows from the target. */
671	RB_FOREACH(wl, winlinks, ww) {
672		wl2 = winlink_add(&s->windows, wl->idx);
673		wl2->session = s;
674		winlink_set_window(wl2, wl->window);
675		notify_session_window("window-linked", s, wl2->window);
676		wl2->flags |= wl->flags & WINLINK_ALERTFLAGS;
677	}
678
679	/* Fix up the current window. */
680	if (s->curw != NULL)
681		s->curw = winlink_find_by_index(&s->windows, s->curw->idx);
682	else
683		s->curw = winlink_find_by_index(&s->windows, target->curw->idx);
684
685	/* Fix up the last window stack. */
686	memcpy(&old_lastw, &s->lastw, sizeof old_lastw);
687	TAILQ_INIT(&s->lastw);
688	TAILQ_FOREACH(wl, &old_lastw, sentry) {
689		wl2 = winlink_find_by_index(&s->windows, wl->idx);
690		if (wl2 != NULL)
691			TAILQ_INSERT_TAIL(&s->lastw, wl2, sentry);
692	}
693
694	/* Then free the old winlinks list. */
695	while (!RB_EMPTY(&old_windows)) {
696		wl = RB_ROOT(&old_windows);
697		wl2 = winlink_find_by_window_id(&s->windows, wl->window->id);
698		if (wl2 == NULL)
699			notify_session_window("window-unlinked", s, wl->window);
700		winlink_remove(&old_windows, wl);
701	}
702}
703
704/* Renumber the windows across winlinks attached to a specific session. */
705void
706session_renumber_windows(struct session *s)
707{
708	struct winlink		*wl, *wl1, *wl_new;
709	struct winlinks		 old_wins;
710	struct winlink_stack	 old_lastw;
711	int			 new_idx, new_curw_idx;
712
713	/* Save and replace old window list. */
714	memcpy(&old_wins, &s->windows, sizeof old_wins);
715	RB_INIT(&s->windows);
716
717	/* Start renumbering from the base-index if it's set. */
718	new_idx = options_get_number(s->options, "base-index");
719	new_curw_idx = 0;
720
721	/* Go through the winlinks and assign new indexes. */
722	RB_FOREACH(wl, winlinks, &old_wins) {
723		wl_new = winlink_add(&s->windows, new_idx);
724		wl_new->session = s;
725		winlink_set_window(wl_new, wl->window);
726		wl_new->flags |= wl->flags & WINLINK_ALERTFLAGS;
727
728		if (wl == s->curw)
729			new_curw_idx = wl_new->idx;
730
731		new_idx++;
732	}
733
734	/* Fix the stack of last windows now. */
735	memcpy(&old_lastw, &s->lastw, sizeof old_lastw);
736	TAILQ_INIT(&s->lastw);
737	TAILQ_FOREACH(wl, &old_lastw, sentry) {
738		wl_new = winlink_find_by_window(&s->windows, wl->window);
739		if (wl_new != NULL)
740			TAILQ_INSERT_TAIL(&s->lastw, wl_new, sentry);
741	}
742
743	/* Set the current window. */
744	s->curw = winlink_find_by_index(&s->windows, new_curw_idx);
745
746	/* Free the old winlinks (reducing window references too). */
747	RB_FOREACH_SAFE(wl, winlinks, &old_wins, wl1)
748		winlink_remove(&old_wins, wl);
749}
750