src/login/logind-core.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <fcntl.h>
   4 #include <sys/ioctl.h>
   5 #include <sys/types.h>
   6 #include <linux/vt.h>
   7
   8 #include "sd-device.h"
   9
  10 #include "alloc-util.h"
  11 #include "bus-error.h"
  12 #include "bus-util.h"
  13 #include "cgroup-util.h"
  14 #include "conf-parser.h"
  15 #include "device-util.h"
  16 #include "efi-loader.h"
  17 #include "errno-util.h"
  18 #include "fd-util.h"
  19 #include "limits-util.h"
  20 #include "logind.h"
  21 #include "parse-util.h"
  22 #include "path-util.h"
  23 #include "process-util.h"
  24 #include "strv.h"
  25 #include "terminal-util.h"
  26 #include "udev-util.h"
  27 #include "user-util.h"
  28 #include "userdb.h"
  29 #include "utmp-wtmp.h"
  30
  31 void manager_reset_config(Manager *m) {
  32         assert(m);
  33
  34         m->n_autovts = 6;
  35         m->reserve_vt = 6;
  36         m->remove_ipc = true;
  37         m->inhibit_delay_max = 5 * USEC_PER_SEC;
  38         m->user_stop_delay = 10 * USEC_PER_SEC;
  39
  40         m->handle_power_key = HANDLE_POWEROFF;
  41         m->handle_suspend_key = HANDLE_SUSPEND;
  42         m->handle_hibernate_key = HANDLE_HIBERNATE;
  43         m->handle_lid_switch = HANDLE_SUSPEND;
  44         m->handle_lid_switch_ep = _HANDLE_ACTION_INVALID;
  45         m->handle_lid_switch_docked = HANDLE_IGNORE;
  46         m->handle_reboot_key = HANDLE_REBOOT;
  47         m->power_key_ignore_inhibited = false;
  48         m->suspend_key_ignore_inhibited = false;
  49         m->hibernate_key_ignore_inhibited = false;
  50         m->lid_switch_ignore_inhibited = true;
  51         m->reboot_key_ignore_inhibited = false;
  52
  53         m->holdoff_timeout_usec = 30 * USEC_PER_SEC;
  54
  55         m->idle_action_usec = 30 * USEC_PER_MINUTE;
  56         m->idle_action = HANDLE_IGNORE;
  57
  58         m->runtime_dir_size = physical_memory_scale(10U, 100U); /* 10% */
  59         m->runtime_dir_inodes = DIV_ROUND_UP(m->runtime_dir_size, 4096); /* 4k per inode */
  60         m->sessions_max = 8192;
  61         m->inhibitors_max = 8192;
  62
  63         m->kill_user_processes = KILL_USER_PROCESSES;
  64
  65         m->kill_only_users = strv_free(m->kill_only_users);
  66         m->kill_exclude_users = strv_free(m->kill_exclude_users);
  67 }
  68
  69 int manager_parse_config_file(Manager *m) {
  70         assert(m);
  71
  72         return config_parse_many_nulstr(
  73                         PKGSYSCONFDIR "/logind.conf",
  74                         CONF_PATHS_NULSTR("systemd/logind.conf.d"),
  75                         "Login\0",
  76                         config_item_perf_lookup, logind_gperf_lookup,
  77                         CONFIG_PARSE_WARN, m,
  78                         NULL);
  79 }
  80
  81 int manager_add_device(Manager *m, const char *sysfs, bool master, Device **ret_device) {
  82         Device *d;
  83
  84         assert(m);
  85         assert(sysfs);
  86
  87         d = hashmap_get(m->devices, sysfs);
  88         if (d)
  89                 /* we support adding master-flags, but not removing them */
  90                 d->master = d->master || master;
  91         else {
  92                 d = device_new(m, sysfs, master);
  93                 if (!d)
  94                         return -ENOMEM;
  95         }
  96
  97         if (ret_device)
  98                 *ret_device = d;
  99
 100         return 0;
 101 }
 102
 103 int manager_add_seat(Manager *m, const char *id, Seat **ret_seat) {
 104         Seat *s;
 105         int r;
 106
 107         assert(m);
 108         assert(id);
 109
 110         s = hashmap_get(m->seats, id);
 111         if (!s) {
 112                 r = seat_new(&s, m, id);
 113                 if (r < 0)
 114                         return r;
 115         }
 116
 117         if (ret_seat)
 118                 *ret_seat = s;
 119
 120         return 0;
 121 }
 122
 123 int manager_add_session(Manager *m, const char *id, Session **ret_session) {
 124         Session *s;
 125         int r;
 126
 127         assert(m);
 128         assert(id);
 129
 130         s = hashmap_get(m->sessions, id);
 131         if (!s) {
 132                 r = session_new(&s, m, id);
 133                 if (r < 0)
 134                         return r;
 135         }
 136
 137         if (ret_session)
 138                 *ret_session = s;
 139
 140         return 0;
 141 }
 142
 143 int manager_add_user(
 144                 Manager *m,
 145                 UserRecord *ur,
 146                 User **ret_user) {
 147
 148         User *u;
 149         int r;
 150
 151         assert(m);
 152         assert(ur);
 153
 154         u = hashmap_get(m->users, UID_TO_PTR(ur->uid));
 155         if (!u) {
 156                 r = user_new(&u, m, ur);
 157                 if (r < 0)
 158                         return r;
 159         }
 160
 161         if (ret_user)
 162                 *ret_user = u;
 163
 164         return 0;
 165 }
 166
 167 int manager_add_user_by_name(
 168                 Manager *m,
 169                 const char *name,
 170                 User **ret_user) {
 171
 172         _cleanup_(user_record_unrefp) UserRecord *ur = NULL;
 173         int r;
 174
 175         assert(m);
 176         assert(name);
 177
 178         r = userdb_by_name(name, USERDB_AVOID_SHADOW, &ur);
 179         if (r < 0)
 180                 return r;
 181
 182         return manager_add_user(m, ur, ret_user);
 183 }
 184
 185 int manager_add_user_by_uid(
 186                 Manager *m,
 187                 uid_t uid,
 188                 User **ret_user) {
 189
 190         _cleanup_(user_record_unrefp) UserRecord *ur = NULL;
 191         int r;
 192
 193         assert(m);
 194         assert(uid_is_valid(uid));
 195
 196         r = userdb_by_uid(uid, USERDB_AVOID_SHADOW, &ur);
 197         if (r < 0)
 198                 return r;
 199
 200         return manager_add_user(m, ur, ret_user);
 201 }
 202
 203 int manager_add_inhibitor(Manager *m, const char* id, Inhibitor **ret) {
 204         Inhibitor *i;
 205         int r;
 206
 207         assert(m);
 208         assert(id);
 209
 210         i = hashmap_get(m->inhibitors, id);
 211         if (!i) {
 212                 r = inhibitor_new(&i, m, id);
 213                 if (r < 0)
 214                         return r;
 215         }
 216
 217         if (ret)
 218                 *ret = i;
 219
 220         return 0;
 221 }
 222
 223 int manager_add_button(Manager *m, const char *name, Button **ret_button) {
 224         Button *b;
 225
 226         assert(m);
 227         assert(name);
 228
 229         b = hashmap_get(m->buttons, name);
 230         if (!b) {
 231                 b = button_new(m, name);
 232                 if (!b)
 233                         return -ENOMEM;
 234         }
 235
 236         if (ret_button)
 237                 *ret_button = b;
 238
 239         return 0;
 240 }
 241
 242 int manager_process_seat_device(Manager *m, sd_device *d) {
 243         Device *device;
 244         int r;
 245
 246         assert(m);
 247
 248         if (device_for_action(d, DEVICE_ACTION_REMOVE) ||
 249             sd_device_has_current_tag(d, "seat") <= 0) {
 250                 const char *syspath;
 251
 252                 r = sd_device_get_syspath(d, &syspath);
 253                 if (r < 0)
 254                         return 0;
 255
 256                 device = hashmap_get(m->devices, syspath);
 257                 if (!device)
 258                         return 0;
 259
 260                 seat_add_to_gc_queue(device->seat);
 261                 device_free(device);
 262
 263         } else {
 264                 const char *sn, *syspath;
 265                 bool master;
 266                 Seat *seat;
 267
 268                 if (sd_device_get_property_value(d, "ID_SEAT", &sn) < 0 || isempty(sn))
 269                         sn = "seat0";
 270
 271                 if (!seat_name_is_valid(sn)) {
 272                         log_device_warning(d, "Device with invalid seat name %s found, ignoring.", sn);
 273                         return 0;
 274                 }
 275
 276                 seat = hashmap_get(m->seats, sn);
 277                 master = sd_device_has_current_tag(d, "master-of-seat") > 0;
 278
 279                 /* Ignore non-master devices for unknown seats */
 280                 if (!master && !seat)
 281                         return 0;
 282
 283                 r = sd_device_get_syspath(d, &syspath);
 284                 if (r < 0)
 285                         return r;
 286
 287                 r = manager_add_device(m, syspath, master, &device);
 288                 if (r < 0)
 289                         return r;
 290
 291                 if (!seat) {
 292                         r = manager_add_seat(m, sn, &seat);
 293                         if (r < 0) {
 294                                 if (!device->seat)
 295                                         device_free(device);
 296
 297                                 return r;
 298                         }
 299                 }
 300
 301                 device_attach(device, seat);
 302                 seat_start(seat);
 303         }
 304
 305         return 0;
 306 }
 307
 308 int manager_process_button_device(Manager *m, sd_device *d) {
 309         const char *sysname;
 310         Button *b;
 311         int r;
 312
 313         assert(m);
 314
 315         r = sd_device_get_sysname(d, &sysname);
 316         if (r < 0)
 317                 return r;
 318
 319         if (device_for_action(d, DEVICE_ACTION_REMOVE) ||
 320             sd_device_has_current_tag(d, "power-switch") <= 0) {
 321
 322                 b = hashmap_get(m->buttons, sysname);
 323                 if (!b)
 324                         return 0;
 325
 326                 button_free(b);
 327
 328         } else {
 329                 const char *sn;
 330
 331                 r = manager_add_button(m, sysname, &b);
 332                 if (r < 0)
 333                         return r;
 334
 335                 if (sd_device_get_property_value(d, "ID_SEAT", &sn) < 0 || isempty(sn))
 336                         sn = "seat0";
 337
 338                 button_set_seat(b, sn);
 339
 340                 r = button_open(b);
 341                 if (r < 0) /* event device doesn't have any keys or switches relevant to us? (or any other error
 342                             * opening the device?) let's close the button again. */
 343                         button_free(b);
 344         }
 345
 346         return 0;
 347 }
 348
 349 int manager_get_session_by_pid(Manager *m, pid_t pid, Session **ret) {
 350         _cleanup_free_ char *unit = NULL;
 351         Session *s;
 352         int r;
 353
 354         assert(m);
 355
 356         if (!pid_is_valid(pid))
 357                 return -EINVAL;
 358
 359         s = hashmap_get(m->sessions_by_leader, PID_TO_PTR(pid));
 360         if (!s) {
 361                 r = cg_pid_get_unit(pid, &unit);
 362                 if (r >= 0)
 363                         s = hashmap_get(m->session_units, unit);
 364         }
 365
 366         if (ret)
 367                 *ret = s;
 368
 369         return !!s;
 370 }
 371
 372 int manager_get_user_by_pid(Manager *m, pid_t pid, User **ret) {
 373         _cleanup_free_ char *unit = NULL;
 374         User *u = NULL;
 375         int r;
 376
 377         assert(m);
 378
 379         if (!pid_is_valid(pid))
 380                 return -EINVAL;
 381
 382         r = cg_pid_get_slice(pid, &unit);
 383         if (r >= 0)
 384                 u = hashmap_get(m->user_units, unit);
 385
 386         if (ret)
 387                 *ret = u;
 388
 389         return !!u;
 390 }
 391
 392 int manager_get_idle_hint(Manager *m, dual_timestamp *t) {
 393         Session *s;
 394         bool idle_hint;
 395         dual_timestamp ts = DUAL_TIMESTAMP_NULL;
 396
 397         assert(m);
 398
 399         idle_hint = !manager_is_inhibited(m, INHIBIT_IDLE, INHIBIT_BLOCK, t, false, false, 0, NULL);
 400
 401         HASHMAP_FOREACH(s, m->sessions) {
 402                 dual_timestamp k;
 403                 int ih;
 404
 405                 ih = session_get_idle_hint(s, &k);
 406                 if (ih < 0)
 407                         return ih;
 408
 409                 if (!ih) {
 410                         if (!idle_hint) {
 411                                 if (k.monotonic < ts.monotonic)
 412                                         ts = k;
 413                         } else {
 414                                 idle_hint = false;
 415                                 ts = k;
 416                         }
 417                 } else if (idle_hint) {
 418
 419                         if (k.monotonic > ts.monotonic)
 420                                 ts = k;
 421                 }
 422         }
 423
 424         if (t)
 425                 *t = ts;
 426
 427         return idle_hint;
 428 }
 429
 430 bool manager_shall_kill(Manager *m, const char *user) {
 431         assert(m);
 432         assert(user);
 433
 434         if (!m->kill_exclude_users && streq(user, "root"))
 435                 return false;
 436
 437         if (strv_contains(m->kill_exclude_users, user))
 438                 return false;
 439
 440         if (!strv_isempty(m->kill_only_users))
 441                 return strv_contains(m->kill_only_users, user);
 442
 443         return m->kill_user_processes;
 444 }
 445
 446 int config_parse_n_autovts(
 447                 const char *unit,
 448                 const char *filename,
 449                 unsigned line,
 450                 const char *section,
 451                 unsigned section_line,
 452                 const char *lvalue,
 453                 int ltype,
 454                 const char *rvalue,
 455                 void *data,
 456                 void *userdata) {
 457
 458         unsigned *n = data;
 459         unsigned o;
 460         int r;
 461
 462         assert(filename);
 463         assert(lvalue);
 464         assert(rvalue);
 465         assert(data);
 466
 467         r = safe_atou(rvalue, &o);
 468         if (r < 0) {
 469                 log_syntax(unit, LOG_WARNING, filename, line, r,
 470                            "Failed to parse number of autovts, ignoring: %s", rvalue);
 471                 return 0;
 472         }
 473
 474         if (o > 15) {
 475                 log_syntax(unit, LOG_WARNING, filename, line, 0,
 476                            "A maximum of 15 autovts are supported, ignoring: %s", rvalue);
 477                 return 0;
 478         }
 479
 480         *n = o;
 481         return 0;
 482 }
 483
 484 static int vt_is_busy(unsigned vtnr) {
 485         struct vt_stat vt_stat;
 486         int r;
 487         _cleanup_close_ int fd;
 488
 489         assert(vtnr >= 1);
 490
 491         /* VT_GETSTATE "cannot return state for more than 16 VTs, since v_state is short" */
 492         assert(vtnr <= 15);
 493
 494         /* We explicitly open /dev/tty1 here instead of /dev/tty0. If
 495          * we'd open the latter we'd open the foreground tty which
 496          * hence would be unconditionally busy. By opening /dev/tty1
 497          * we avoid this. Since tty1 is special and needs to be an
 498          * explicitly loaded getty or DM this is safe. */
 499
 500         fd = open_terminal("/dev/tty1", O_RDWR|O_NOCTTY|O_CLOEXEC);
 501         if (fd < 0)
 502                 return -errno;
 503
 504         if (ioctl(fd, VT_GETSTATE, &vt_stat) < 0)
 505                 r = -errno;
 506         else
 507                 r = !!(vt_stat.v_state & (1 << vtnr));
 508
 509         return r;
 510 }
 511
 512 int manager_spawn_autovt(Manager *m, unsigned vtnr) {
 513         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 514         char name[sizeof("autovt@tty.service") + DECIMAL_STR_MAX(unsigned)];
 515         int r;
 516
 517         assert(m);
 518         assert(vtnr >= 1);
 519
 520         if (vtnr > m->n_autovts &&
 521             vtnr != m->reserve_vt)
 522                 return 0;
 523
 524         if (vtnr != m->reserve_vt) {
 525                 /* If this is the reserved TTY, we'll start the getty
 526                  * on it in any case, but otherwise only if it is not
 527                  * busy. */
 528
 529                 r = vt_is_busy(vtnr);
 530                 if (r < 0)
 531                         return r;
 532                 else if (r > 0)
 533                         return -EBUSY;
 534         }
 535
 536         snprintf(name, sizeof(name), "autovt@tty%u.service", vtnr);
 537         r = sd_bus_call_method(
 538                         m->bus,
 539                         "org.freedesktop.systemd1",
 540                         "/org/freedesktop/systemd1",
 541                         "org.freedesktop.systemd1.Manager",
 542                         "StartUnit",
 543                         &error,
 544                         NULL,
 545                         "ss", name, "fail");
 546         if (r < 0)
 547                 return log_error_errno(r, "Failed to start %s: %s", name, bus_error_message(&error, r));
 548
 549         return 0;
 550 }
 551
 552 bool manager_is_lid_closed(Manager *m) {
 553         Button *b;
 554
 555         HASHMAP_FOREACH(b, m->buttons)
 556                 if (b->lid_closed)
 557                         return true;
 558
 559         return false;
 560 }
 561
 562 static bool manager_is_docked(Manager *m) {
 563         Button *b;
 564
 565         HASHMAP_FOREACH(b, m->buttons)
 566                 if (b->docked)
 567                         return true;
 568
 569         return false;
 570 }
 571
 572 static int manager_count_external_displays(Manager *m) {
 573         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 574         sd_device *d;
 575         int r, n = 0;
 576
 577         r = sd_device_enumerator_new(&e);
 578         if (r < 0)
 579                 return r;
 580
 581         r = sd_device_enumerator_allow_uninitialized(e);
 582         if (r < 0)
 583                 return r;
 584
 585         r = sd_device_enumerator_add_match_subsystem(e, "drm", true);
 586         if (r < 0)
 587                 return r;
 588
 589         FOREACH_DEVICE(e, d) {
 590                 const char *status, *enabled, *dash, *nn, *subsys;
 591                 sd_device *p;
 592
 593                 if (sd_device_get_parent(d, &p) < 0)
 594                         continue;
 595
 596                 /* If the parent shares the same subsystem as the
 597                  * device we are looking at then it is a connector,
 598                  * which is what we are interested in. */
 599                 if (sd_device_get_subsystem(p, &subsys) < 0 || !streq(subsys, "drm"))
 600                         continue;
 601
 602                 if (sd_device_get_sysname(d, &nn) < 0)
 603                         continue;
 604
 605                 /* Ignore internal displays: the type is encoded in the sysfs name, as the second dash
 606                  * separated item (the first is the card name, the last the connector number). We implement a
 607                  * deny list of external displays here, rather than an allow list of internal ones, to ensure
 608                  * we don't block suspends too eagerly. */
 609                 dash = strchr(nn, '-');
 610                 if (!dash)
 611                         continue;
 612
 613                 dash++;
 614                 if (!STARTSWITH_SET(dash,
 615                                     "VGA-", "DVI-I-", "DVI-D-", "DVI-A-"
 616                                     "Composite-", "SVIDEO-", "Component-",
 617                                     "DIN-", "DP-", "HDMI-A-", "HDMI-B-", "TV-"))
 618                         continue;
 619
 620                 /* Ignore ports that are not enabled */
 621                 if (sd_device_get_sysattr_value(d, "enabled", &enabled) < 0 || !streq(enabled, "enabled"))
 622                         continue;
 623
 624                 /* We count any connector which is not explicitly
 625                  * "disconnected" as connected. */
 626                 if (sd_device_get_sysattr_value(d, "status", &status) < 0 || !streq(status, "disconnected"))
 627                         n++;
 628         }
 629
 630         return n;
 631 }
 632
 633 bool manager_is_docked_or_external_displays(Manager *m) {
 634         int n;
 635
 636         /* If we are docked don't react to lid closing */
 637         if (manager_is_docked(m)) {
 638                 log_debug("System is docked.");
 639                 return true;
 640         }
 641
 642         /* If we have more than one display connected,
 643          * assume that we are docked. */
 644         n = manager_count_external_displays(m);
 645         if (n < 0)
 646                 log_warning_errno(n, "Display counting failed: %m");
 647         else if (n >= 1) {
 648                 log_debug("External (%i) displays connected.", n);
 649                 return true;
 650         }
 651
 652         return false;
 653 }
 654
 655 bool manager_is_on_external_power(void) {
 656         int r;
 657
 658         /* For now we only check for AC power, but 'external power' can apply to anything that isn't an internal
 659          * battery */
 660         r = on_ac_power();
 661         if (r < 0)
 662                 log_warning_errno(r, "Failed to read AC power status: %m");
 663
 664         return r != 0; /* Treat failure as 'on AC' */
 665 }
 666
 667 bool manager_all_buttons_ignored(Manager *m) {
 668         assert(m);
 669
 670         if (m->handle_power_key != HANDLE_IGNORE)
 671                 return false;
 672         if (m->handle_suspend_key != HANDLE_IGNORE)
 673                 return false;
 674         if (m->handle_hibernate_key != HANDLE_IGNORE)
 675                 return false;
 676         if (m->handle_lid_switch != HANDLE_IGNORE)
 677                 return false;
 678         if (!IN_SET(m->handle_lid_switch_ep, _HANDLE_ACTION_INVALID, HANDLE_IGNORE))
 679                 return false;
 680         if (m->handle_lid_switch_docked != HANDLE_IGNORE)
 681                 return false;
 682         if (m->handle_reboot_key != HANDLE_IGNORE)
 683                 return false;
 684
 685         return true;
 686 }
 687
 688 int manager_read_utmp(Manager *m) {
 689 #if ENABLE_UTMP
 690         int r;
 691         _cleanup_(utxent_cleanup) bool utmpx = false;
 692
 693         assert(m);
 694
 695         if (utmpxname(_PATH_UTMPX) < 0)
 696                 return log_error_errno(errno, "Failed to set utmp path to " _PATH_UTMPX ": %m");
 697
 698         utmpx = utxent_start();
 699
 700         for (;;) {
 701                 _cleanup_free_ char *t = NULL;
 702                 struct utmpx *u;
 703                 const char *c;
 704                 Session *s;
 705
 706                 errno = 0;
 707                 u = getutxent();
 708                 if (!u) {
 709                         if (errno != 0)
 710                                 log_warning_errno(errno, "Failed to read " _PATH_UTMPX ", ignoring: %m");
 711                         return 0;
 712                 }
 713
 714                 if (u->ut_type != USER_PROCESS)
 715                         continue;
 716
 717                 if (!pid_is_valid(u->ut_pid))
 718                         continue;
 719
 720                 t = strndup(u->ut_line, sizeof(u->ut_line));
 721                 if (!t)
 722                         return log_oom();
 723
 724                 c = path_startswith(t, "/dev/");
 725                 if (c) {
 726                         r = free_and_strdup(&t, c);
 727                         if (r < 0)
 728                                 return log_oom();
 729                 }
 730
 731                 if (isempty(t))
 732                         continue;
 733
 734                 s = hashmap_get(m->sessions_by_leader, PID_TO_PTR(u->ut_pid));
 735                 if (!s)
 736                         continue;
 737
 738                 if (s->tty_validity == TTY_FROM_UTMP && !streq_ptr(s->tty, t)) {
 739                         /* This may happen on multiplexed SSH connection (i.e. 'SSH connection sharing'). In
 740                          * this case PAM and utmp sessions don't match. In such a case let's invalidate the TTY
 741                          * information and never acquire it again. */
 742
 743                         s->tty = mfree(s->tty);
 744                         s->tty_validity = TTY_UTMP_INCONSISTENT;
 745                         log_debug("Session '%s' has inconsistent TTY information, dropping TTY information.", s->id);
 746                         continue;
 747                 }
 748
 749                 /* Never override what we figured out once */
 750                 if (s->tty || s->tty_validity >= 0)
 751                         continue;
 752
 753                 s->tty = TAKE_PTR(t);
 754                 s->tty_validity = TTY_FROM_UTMP;
 755                 log_debug("Acquired TTY information '%s' from utmp for session '%s'.", s->tty, s->id);
 756         }
 757
 758 #else
 759         return 0;
 760 #endif
 761 }
 762
 763 #if ENABLE_UTMP
 764 static int manager_dispatch_utmp(sd_event_source *s, const struct inotify_event *event, void *userdata) {
 765         Manager *m = userdata;
 766
 767         assert(m);
 768
 769         /* If there's indication the file itself might have been removed or became otherwise unavailable, then let's
 770          * reestablish the watch on whatever there's now. */
 771         if ((event->mask & (IN_ATTRIB|IN_DELETE_SELF|IN_MOVE_SELF|IN_Q_OVERFLOW|IN_UNMOUNT)) != 0)
 772                 manager_connect_utmp(m);
 773
 774         (void) manager_read_utmp(m);
 775         return 0;
 776 }
 777 #endif
 778
 779 void manager_connect_utmp(Manager *m) {
 780 #if ENABLE_UTMP
 781         sd_event_source *s = NULL;
 782         int r;
 783
 784         assert(m);
 785
 786         /* Watch utmp for changes via inotify. We do this to deal with tools such as ssh, which will register the PAM
 787          * session early, and acquire a TTY only much later for the connection. Thus during PAM the TTY won't be known
 788          * yet. ssh will register itself with utmp when it finally acquired the TTY. Hence, let's make use of this, and
 789          * watch utmp for the TTY asynchronously. We use the PAM session's leader PID as key, to find the right entry.
 790          *
 791          * Yes, relying on utmp is pretty ugly, but it's good enough for informational purposes, as well as idle
 792          * detection (which, for tty sessions, relies on the TTY used) */
 793
 794         r = sd_event_add_inotify(m->event, &s, _PATH_UTMPX, IN_MODIFY|IN_MOVE_SELF|IN_DELETE_SELF|IN_ATTRIB, manager_dispatch_utmp, m);
 795         if (r < 0)
 796                 log_full_errno(r == -ENOENT ? LOG_DEBUG: LOG_WARNING, r, "Failed to create inotify watch on " _PATH_UTMPX ", ignoring: %m");
 797         else {
 798                 r = sd_event_source_set_priority(s, SD_EVENT_PRIORITY_IDLE);
 799                 if (r < 0)
 800                         log_warning_errno(r, "Failed to adjust utmp event source priority, ignoring: %m");
 801
 802                 (void) sd_event_source_set_description(s, "utmp");
 803         }
 804
 805         sd_event_source_unref(m->utmp_event_source);
 806         m->utmp_event_source = s;
 807 #endif
 808 }
 809
 810 void manager_reconnect_utmp(Manager *m) {
 811 #if ENABLE_UTMP
 812         assert(m);
 813
 814         if (m->utmp_event_source)
 815                 return;
 816
 817         manager_connect_utmp(m);
 818 #endif
 819 }
 820
 821 int manager_read_efi_boot_loader_entries(Manager *m) {
 822 #if ENABLE_EFI
 823         int r;
 824
 825         assert(m);
 826         if (m->efi_boot_loader_entries_set)
 827                 return 0;
 828
 829         r = efi_loader_get_entries(&m->efi_boot_loader_entries);
 830         if (r == -ENOENT || ERRNO_IS_NOT_SUPPORTED(r)) {
 831                 log_debug_errno(r, "Boot loader reported no entries.");
 832                 m->efi_boot_loader_entries_set = true;
 833                 return 0;
 834         }
 835         if (r < 0)
 836                 return log_error_errno(r, "Failed to determine entries reported by boot loader: %m");
 837
 838         m->efi_boot_loader_entries_set = true;
 839         return 1;
 840 #else
 841         return 0;
 842 #endif
 843 }