1 /* SPDX-License-Identifier: LGPL-2.1+ */
3 Copyright 2011 Lennart Poettering
12 #include "sd-messages.h"
14 #include "alloc-util.h"
17 #include "format-util.h"
18 #include "logind-acl.h"
19 #include "logind-seat.h"
21 #include "parse-util.h"
22 #include "stdio-util.h"
23 #include "string-util.h"
24 #include "terminal-util.h"
27 Seat *seat_new(Manager *m, const char *id) {
37 s->state_file = strappend("/run/systemd/seats/", id);
41 s->id = basename(s->state_file);
44 if (hashmap_put(m->seats, s->id, s) < 0) {
52 void seat_free(Seat *s) {
56 LIST_REMOVE(gc_queue, s->manager->seat_gc_queue, s);
59 session_free(s->sessions);
64 device_free(s->devices);
66 hashmap_remove(s->manager->seats, s->id);
73 int seat_save(Seat *s) {
74 _cleanup_free_ char *temp_path = NULL;
75 _cleanup_fclose_ FILE *f = NULL;
83 r = mkdir_safe_label("/run/systemd/seats", 0755, 0, 0, MKDIR_WARN_MODE);
87 r = fopen_temporary(s->state_file, &f, &temp_path);
91 (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
92 (void) fchmod(fileno(f), 0644);
95 "# This is private data. Do not parse.\n"
97 "CAN_MULTI_SESSION=%i\n"
101 seat_can_multi_session(s),
103 seat_can_graphical(s));
106 assert(s->active->user);
110 "ACTIVE_UID="UID_FMT"\n",
112 s->active->user->uid);
118 fputs("SESSIONS=", f);
119 LIST_FOREACH(sessions_by_seat, i, s->sessions) {
123 i->sessions_by_seat_next ? ' ' : '\n');
127 LIST_FOREACH(sessions_by_seat, i, s->sessions)
131 i->sessions_by_seat_next ? ' ' : '\n');
134 r = fflush_and_check(f);
138 if (rename(temp_path, s->state_file) < 0) {
146 (void) unlink(s->state_file);
149 (void) unlink(temp_path);
151 return log_error_errno(r, "Failed to save seat data %s: %m", s->state_file);
154 int seat_load(Seat *s) {
157 /* There isn't actually anything to read here ... */
162 #if 0 /// UNNEEDED by elogind
163 static int vt_allocate(unsigned int vtnr) {
164 char p[sizeof("/dev/tty") + DECIMAL_STR_MAX(unsigned int)];
165 _cleanup_close_ int fd = -1;
169 xsprintf(p, "/dev/tty%u", vtnr);
170 fd = open_terminal(p, O_RDWR|O_NOCTTY|O_CLOEXEC);
177 int seat_preallocate_vts(Seat *s) {
184 log_debug("Preallocating VTs...");
186 if (s->manager->n_autovts <= 0)
189 if (!seat_has_vts(s))
192 for (i = 1; i <= s->manager->n_autovts; i++) {
197 log_error_errno(q, "Failed to preallocate VT %u: %m", i);
206 int seat_apply_acls(Seat *s, Session *old_active) {
211 r = devnode_acl_all(s->manager->udev,
214 !!old_active, old_active ? old_active->user->uid : 0,
215 !!s->active, s->active ? s->active->user->uid : 0);
218 log_error_errno(r, "Failed to apply ACLs: %m");
223 int seat_set_active(Seat *s, Session *session) {
227 assert(!session || session->seat == s);
229 if (session == s->active)
232 old_active = s->active;
236 session_device_pause_all(old_active);
237 session_send_changed(old_active, "Active", NULL);
240 seat_apply_acls(s, old_active);
242 if (session && session->started) {
243 session_send_changed(session, "Active", NULL);
244 session_device_resume_all(session);
247 if (!session || session->started)
248 seat_send_changed(s, "ActiveSession", NULL);
253 session_save(session);
254 user_save(session->user);
258 session_save(old_active);
259 if (!session || session->user != old_active->user)
260 user_save(old_active->user);
266 int seat_switch_to(Seat *s, unsigned int num) {
267 /* Public session positions skip 0 (there is only F1-F12). Maybe it
268 * will get reassigned in the future, so return error for now. */
272 if (num >= s->position_count || !s->positions[num]) {
273 /* allow switching to unused VTs to trigger auto-activate */
274 if (seat_has_vts(s) && num < 64)
280 return session_activate(s->positions[num]);
283 int seat_switch_to_next(Seat *s) {
284 unsigned int start, i;
286 if (s->position_count == 0)
290 if (s->active && s->active->position > 0)
291 start = s->active->position;
293 for (i = start + 1; i < s->position_count; ++i)
295 return session_activate(s->positions[i]);
297 for (i = 1; i < start; ++i)
299 return session_activate(s->positions[i]);
304 int seat_switch_to_previous(Seat *s) {
305 unsigned int start, i;
307 if (s->position_count == 0)
311 if (s->active && s->active->position > 0)
312 start = s->active->position;
314 for (i = start - 1; i > 0; --i)
316 return session_activate(s->positions[i]);
318 for (i = s->position_count - 1; i > start; --i)
320 return session_activate(s->positions[i]);
325 int seat_active_vt_changed(Seat *s, unsigned int vtnr) {
326 Session *i, *new_active = NULL;
332 if (!seat_has_vts(s))
335 log_debug("VT changed to %u", vtnr);
337 /* we might have earlier closing sessions on the same VT, so try to
338 * find a running one first */
339 LIST_FOREACH(sessions_by_seat, i, s->sessions)
340 if (i->vtnr == vtnr && !i->stopping) {
346 /* no running one? then we can't decide which one is the
347 * active one, let the first one win */
348 LIST_FOREACH(sessions_by_seat, i, s->sessions)
349 if (i->vtnr == vtnr) {
355 r = seat_set_active(s, new_active);
356 #if 0 /// elogind does not spawn autovt
357 manager_spawn_autovt(s->manager, vtnr);
363 int seat_read_active_vt(Seat *s) {
371 if (!seat_has_vts(s))
374 if (lseek(s->manager->console_active_fd, SEEK_SET, 0) < 0)
375 return log_error_errno(errno, "lseek on console_active_fd failed: %m");
377 k = read(s->manager->console_active_fd, t, sizeof(t)-1);
379 log_error("Failed to read current console: %s", k < 0 ? strerror(-errno) : "EOF");
380 return k < 0 ? -errno : -EIO;
386 if (!startswith(t, "tty")) {
387 log_error("Hm, /sys/class/tty/tty0/active is badly formatted.");
391 r = safe_atou(t+3, &vtnr);
393 return log_error_errno(r, "Failed to parse VT number \"%s\": %m", t+3);
396 log_error("VT number invalid: %s", t+3);
400 return seat_active_vt_changed(s, vtnr);
403 int seat_start(Seat *s) {
410 "MESSAGE_ID=" SD_MESSAGE_SEAT_START_STR,
412 LOG_MESSAGE("New seat %s.", s->id));
414 /* Initialize VT magic stuff */
415 #if 0 /// elogind does not support autospawning vts
416 seat_preallocate_vts(s);
419 /* Read current VT */
420 seat_read_active_vt(s);
427 seat_send_signal(s, true);
432 int seat_stop(Seat *s, bool force) {
439 "MESSAGE_ID=" SD_MESSAGE_SEAT_STOP_STR,
441 LOG_MESSAGE("Removed seat %s.", s->id));
443 seat_stop_sessions(s, force);
445 unlink(s->state_file);
446 seat_add_to_gc_queue(s);
449 seat_send_signal(s, false);
456 int seat_stop_sessions(Seat *s, bool force) {
462 LIST_FOREACH(sessions_by_seat, session, s->sessions) {
463 k = session_stop(session, force);
471 void seat_evict_position(Seat *s, Session *session) {
473 unsigned int pos = session->position;
475 session->position = 0;
480 if (pos < s->position_count && s->positions[pos] == session) {
481 s->positions[pos] = NULL;
483 /* There might be another session claiming the same
484 * position (eg., during gdm->session transition), so let's look
485 * for it and set it on the free slot. */
486 LIST_FOREACH(sessions_by_seat, iter, s->sessions) {
487 if (iter->position == pos && session_get_state(iter) != SESSION_CLOSING) {
488 s->positions[pos] = iter;
495 void seat_claim_position(Seat *s, Session *session, unsigned int pos) {
496 /* with VTs, the position is always the same as the VTnr */
500 if (!GREEDY_REALLOC0(s->positions, s->position_count, pos + 1))
503 seat_evict_position(s, session);
505 session->position = pos;
507 s->positions[pos] = session;
510 static void seat_assign_position(Seat *s, Session *session) {
513 if (session->position > 0)
516 for (pos = 1; pos < s->position_count; ++pos)
517 if (!s->positions[pos])
520 seat_claim_position(s, session, pos);
523 int seat_attach_session(Seat *s, Session *session) {
526 assert(!session->seat);
528 if (!seat_has_vts(s) != !session->vtnr)
532 LIST_PREPEND(sessions_by_seat, s->sessions, session);
533 seat_assign_position(s, session);
535 /* On seats with VTs, the VT logic defines which session is active. On
536 * seats without VTs, we automatically activate new sessions. */
537 if (!seat_has_vts(s))
538 seat_set_active(s, session);
543 void seat_complete_switch(Seat *s) {
548 /* if no session-switch is pending or if it got canceled, do nothing */
549 if (!s->pending_switch)
552 session = TAKE_PTR(s->pending_switch);
554 seat_set_active(s, session);
557 bool seat_has_vts(Seat *s) {
560 return seat_is_seat0(s) && s->manager->console_active_fd >= 0;
563 bool seat_is_seat0(Seat *s) {
566 return s->manager->seat0 == s;
569 bool seat_can_multi_session(Seat *s) {
572 return seat_has_vts(s);
575 bool seat_can_tty(Seat *s) {
578 return seat_has_vts(s);
581 bool seat_has_master_device(Seat *s) {
584 /* device list is ordered by "master" flag */
585 return !!s->devices && s->devices->master;
588 bool seat_can_graphical(Seat *s) {
591 return seat_has_master_device(s);
594 int seat_get_idle_hint(Seat *s, dual_timestamp *t) {
596 bool idle_hint = true;
597 dual_timestamp ts = DUAL_TIMESTAMP_NULL;
601 LIST_FOREACH(sessions_by_seat, session, s->sessions) {
605 ih = session_get_idle_hint(session, &k);
611 if (k.monotonic > ts.monotonic)
617 } else if (idle_hint) {
619 if (k.monotonic > ts.monotonic)
630 bool seat_may_gc(Seat *s, bool drop_not_started) {
633 if (drop_not_started && !s->started)
636 if (seat_is_seat0(s))
639 return !seat_has_master_device(s);
642 void seat_add_to_gc_queue(Seat *s) {
648 LIST_PREPEND(gc_queue, s->manager->seat_gc_queue, s);
649 s->in_gc_queue = true;
652 static bool seat_name_valid_char(char c) {
654 (c >= 'a' && c <= 'z') ||
655 (c >= 'A' && c <= 'Z') ||
656 (c >= '0' && c <= '9') ||
660 bool seat_name_is_valid(const char *name) {
665 if (!startswith(name, "seat"))
671 for (p = name; *p; p++)
672 if (!seat_name_valid_char(*p))
675 if (strlen(name) > 255)