src/login/logind-core.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   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 "stdio-util.h"
  25 #include "strv.h"
  26 #include "terminal-util.h"
  27 #include "udev-util.h"
  28 #include "user-util.h"
  29 #include "userdb.h"
  30 #include "utmp-wtmp.h"
  31
  32 void manager_reset_config(Manager *m) {
  33         assert(m);
  34
  35         m->n_autovts = 6;
  36         m->reserve_vt = 6;
  37         m->remove_ipc = true;
  38         m->inhibit_delay_max = 5 * USEC_PER_SEC;
  39         m->user_stop_delay = 10 * USEC_PER_SEC;
  40
  41         m->handle_power_key = HANDLE_POWEROFF;
  42         m->handle_suspend_key = HANDLE_SUSPEND;
  43         m->handle_hibernate_key = HANDLE_HIBERNATE;
  44         m->handle_lid_switch = HANDLE_SUSPEND;
  45         m->handle_lid_switch_ep = _HANDLE_ACTION_INVALID;
  46         m->handle_lid_switch_docked = HANDLE_IGNORE;
  47         m->handle_reboot_key = HANDLE_REBOOT;
  48         m->power_key_ignore_inhibited = false;
  49         m->suspend_key_ignore_inhibited = false;
  50         m->hibernate_key_ignore_inhibited = false;
  51         m->lid_switch_ignore_inhibited = true;
  52         m->reboot_key_ignore_inhibited = false;
  53
  54         m->holdoff_timeout_usec = 30 * USEC_PER_SEC;
  55
  56         m->idle_action_usec = 30 * USEC_PER_MINUTE;
  57         m->idle_action = HANDLE_IGNORE;
  58
  59         m->runtime_dir_size = physical_memory_scale(10U, 100U); /* 10% */
  60         m->runtime_dir_inodes = DIV_ROUND_UP(m->runtime_dir_size, 4096); /* 4k per inode */
  61         m->sessions_max = 8192;
  62         m->inhibitors_max = 8192;
  63
  64         m->kill_user_processes = KILL_USER_PROCESSES;
  65
  66         m->kill_only_users = strv_free(m->kill_only_users);
  67         m->kill_exclude_users = strv_free(m->kill_exclude_users);
  68 }
  69
  70 int manager_parse_config_file(Manager *m) {
  71         assert(m);
  72
  73         return config_parse_many_nulstr(
  74                         PKGSYSCONFDIR "/logind.conf",
  75                         CONF_PATHS_NULSTR("systemd/logind.conf.d"),
  76                         "Login\0",
  77                         config_item_perf_lookup, logind_gperf_lookup,
  78                         CONFIG_PARSE_WARN, m,
  79                         NULL);
  80 }
  81
  82 int manager_add_device(Manager *m, const char *sysfs, bool master, Device **ret_device) {
  83         Device *d;
  84
  85         assert(m);
  86         assert(sysfs);
  87
  88         d = hashmap_get(m->devices, sysfs);
  89         if (d)
  90                 /* we support adding master-flags, but not removing them */
  91                 d->master = d->master || master;
  92         else {
  93                 d = device_new(m, sysfs, master);
  94                 if (!d)
  95                         return -ENOMEM;
  96         }
  97
  98         if (ret_device)
  99                 *ret_device = d;
 100
 101         return 0;
 102 }
 103
 104 int manager_add_seat(Manager *m, const char *id, Seat **ret_seat) {
 105         Seat *s;
 106         int r;
 107
 108         assert(m);
 109         assert(id);
 110
 111         s = hashmap_get(m->seats, id);
 112         if (!s) {
 113                 r = seat_new(&s, m, id);
 114                 if (r < 0)
 115                         return r;
 116         }
 117
 118         if (ret_seat)
 119                 *ret_seat = s;
 120
 121         return 0;
 122 }
 123
 124 int manager_add_session(Manager *m, const char *id, Session **ret_session) {
 125         Session *s;
 126         int r;
 127
 128         assert(m);
 129         assert(id);
 130
 131         s = hashmap_get(m->sessions, id);
 132         if (!s) {
 133                 r = session_new(&s, m, id);
 134                 if (r < 0)
 135                         return r;
 136         }
 137
 138         if (ret_session)
 139                 *ret_session = s;
 140
 141         return 0;
 142 }
 143
 144 int manager_add_user(
 145                 Manager *m,
 146                 UserRecord *ur,
 147                 User **ret_user) {
 148
 149         User *u;
 150         int r;
 151
 152         assert(m);
 153         assert(ur);
 154
 155         u = hashmap_get(m->users, UID_TO_PTR(ur->uid));
 156         if (!u) {
 157                 r = user_new(&u, m, ur);
 158                 if (r < 0)
 159                         return r;
 160         }
 161
 162         if (ret_user)
 163                 *ret_user = u;
 164
 165         return 0;
 166 }
 167
 168 int manager_add_user_by_name(
 169                 Manager *m,
 170                 const char *name,
 171                 User **ret_user) {
 172
 173         _cleanup_(user_record_unrefp) UserRecord *ur = NULL;
 174         int r;
 175
 176         assert(m);
 177         assert(name);
 178
 179         r = userdb_by_name(name, USERDB_AVOID_SHADOW, &ur);
 180         if (r < 0)
 181                 return r;
 182
 183         return manager_add_user(m, ur, ret_user);
 184 }
 185
 186 int manager_add_user_by_uid(
 187                 Manager *m,
 188                 uid_t uid,
 189                 User **ret_user) {
 190
 191         _cleanup_(user_record_unrefp) UserRecord *ur = NULL;
 192         int r;
 193
 194         assert(m);
 195         assert(uid_is_valid(uid));
 196
 197         r = userdb_by_uid(uid, USERDB_AVOID_SHADOW, &ur);
 198         if (r < 0)
 199                 return r;
 200
 201         return manager_add_user(m, ur, ret_user);
 202 }
 203
 204 int manager_add_inhibitor(Manager *m, const char* id, Inhibitor **ret) {
 205         Inhibitor *i;
 206         int r;
 207
 208         assert(m);
 209         assert(id);
 210
 211         i = hashmap_get(m->inhibitors, id);
 212         if (!i) {
 213                 r = inhibitor_new(&i, m, id);
 214                 if (r < 0)
 215                         return r;
 216         }
 217
 218         if (ret)
 219                 *ret = i;
 220
 221         return 0;
 222 }
 223
 224 int manager_add_button(Manager *m, const char *name, Button **ret_button) {
 225         Button *b;
 226
 227         assert(m);
 228         assert(name);
 229
 230         b = hashmap_get(m->buttons, name);
 231         if (!b) {
 232                 b = button_new(m, name);
 233                 if (!b)
 234                         return -ENOMEM;
 235         }
 236
 237         if (ret_button)
 238                 *ret_button = b;
 239
 240         return 0;
 241 }
 242
 243 int manager_process_seat_device(Manager *m, sd_device *d) {
 244         Device *device;
 245         int r;
 246
 247         assert(m);
 248
 249         if (device_for_action(d, SD_DEVICE_REMOVE) ||
 250             sd_device_has_current_tag(d, "seat") <= 0) {
 251                 const char *syspath;
 252
 253                 r = sd_device_get_syspath(d, &syspath);
 254                 if (r < 0)
 255                         return 0;
 256
 257                 device = hashmap_get(m->devices, syspath);
 258                 if (!device)
 259                         return 0;
 260
 261                 seat_add_to_gc_queue(device->seat);
 262                 device_free(device);
 263
 264         } else {
 265                 const char *sn, *syspath;
 266                 bool master;
 267                 Seat *seat;
 268
 269                 if (sd_device_get_property_value(d, "ID_SEAT", &sn) < 0 || isempty(sn))
 270                         sn = "seat0";
 271
 272                 if (!seat_name_is_valid(sn)) {
 273                         log_device_warning(d, "Device with invalid seat name %s found, ignoring.", sn);
 274                         return 0;
 275                 }
 276
 277                 seat = hashmap_get(m->seats, sn);
 278                 master = sd_device_has_current_tag(d, "master-of-seat") > 0;
 279
 280                 /* Ignore non-master devices for unknown seats */
 281                 if (!master && !seat)
 282                         return 0;
 283
 284                 r = sd_device_get_syspath(d, &syspath);
 285                 if (r < 0)
 286                         return r;
 287
 288                 r = manager_add_device(m, syspath, master, &device);
 289                 if (r < 0)
 290                         return r;
 291
 292                 if (!seat) {
 293                         r = manager_add_seat(m, sn, &seat);
 294                         if (r < 0) {
 295                                 if (!device->seat)
 296                                         device_free(device);
 297
 298                                 return r;
 299                         }
 300                 }
 301
 302                 device_attach(device, seat);
 303                 seat_start(seat);
 304         }
 305
 306         return 0;
 307 }
 308
 309 int manager_process_button_device(Manager *m, sd_device *d) {
 310         const char *sysname;
 311         Button *b;
 312         int r;
 313
 314         assert(m);
 315
 316         r = sd_device_get_sysname(d, &sysname);
 317         if (r < 0)
 318                 return r;
 319
 320         if (device_for_action(d, SD_DEVICE_REMOVE) ||
 321             sd_device_has_current_tag(d, "power-switch") <= 0) {
 322
 323                 b = hashmap_get(m->buttons, sysname);
 324                 if (!b)
 325                         return 0;
 326
 327                 button_free(b);
 328
 329         } else {
 330                 const char *sn;
 331
 332                 r = manager_add_button(m, sysname, &b);
 333                 if (r < 0)
 334                         return r;
 335
 336                 if (sd_device_get_property_value(d, "ID_SEAT", &sn) < 0 || isempty(sn))
 337                         sn = "seat0";
 338
 339                 button_set_seat(b, sn);
 340
 341                 r = button_open(b);
 342                 if (r < 0) /* event device doesn't have any keys or switches relevant to us? (or any other error
 343                             * opening the device?) let's close the button again. */
 344                         button_free(b);
 345         }
 346
 347         return 0;
 348 }
 349
 350 int manager_get_session_by_pid(Manager *m, pid_t pid, Session **ret) {
 351         _cleanup_free_ char *unit = NULL;
 352         Session *s;
 353         int r;
 354
 355         assert(m);
 356
 357         if (!pid_is_valid(pid))
 358                 return -EINVAL;
 359
 360         s = hashmap_get(m->sessions_by_leader, PID_TO_PTR(pid));
 361         if (!s) {
 362                 r = cg_pid_get_unit(pid, &unit);
 363                 if (r >= 0)
 364                         s = hashmap_get(m->session_units, unit);
 365         }
 366
 367         if (ret)
 368                 *ret = s;
 369
 370         return !!s;
 371 }
 372
 373 int manager_get_user_by_pid(Manager *m, pid_t pid, User **ret) {
 374         _cleanup_free_ char *unit = NULL;
 375         User *u = NULL;
 376         int r;
 377
 378         assert(m);
 379
 380         if (!pid_is_valid(pid))
 381                 return -EINVAL;
 382
 383         r = cg_pid_get_slice(pid, &unit);
 384         if (r >= 0)
 385                 u = hashmap_get(m->user_units, unit);
 386
 387         if (ret)
 388                 *ret = u;
 389
 390         return !!u;
 391 }
 392
 393 int manager_get_idle_hint(Manager *m, dual_timestamp *t) {
 394         Session *s;
 395         bool idle_hint;
 396         dual_timestamp ts = DUAL_TIMESTAMP_NULL;
 397
 398         assert(m);
 399
 400         idle_hint = !manager_is_inhibited(m, INHIBIT_IDLE, INHIBIT_BLOCK, t, false, false, 0, NULL);
 401
 402         HASHMAP_FOREACH(s, m->sessions) {
 403                 dual_timestamp k;
 404                 int ih;
 405
 406                 ih = session_get_idle_hint(s, &k);
 407                 if (ih < 0)
 408                         return ih;
 409
 410                 if (!ih) {
 411                         if (!idle_hint) {
 412                                 if (k.monotonic < ts.monotonic)
 413                                         ts = k;
 414                         } else {
 415                                 idle_hint = false;
 416                                 ts = k;
 417                         }
 418                 } else if (idle_hint) {
 419
 420                         if (k.monotonic > ts.monotonic)
 421                                 ts = k;
 422                 }
 423         }
 424
 425         if (t)
 426                 *t = ts;
 427
 428         return idle_hint;
 429 }
 430
 431 bool manager_shall_kill(Manager *m, const char *user) {
 432         assert(m);
 433         assert(user);
 434
 435         if (!m->kill_exclude_users && streq(user, "root"))
 436                 return false;
 437
 438         if (strv_contains(m->kill_exclude_users, user))
 439                 return false;
 440
 441         if (!strv_isempty(m->kill_only_users))
 442                 return strv_contains(m->kill_only_users, user);
 443
 444         return m->kill_user_processes;
 445 }
 446
 447 int config_parse_n_autovts(
 448                 const char *unit,
 449                 const char *filename,
 450                 unsigned line,
 451                 const char *section,
 452                 unsigned section_line,
 453                 const char *lvalue,
 454                 int ltype,
 455                 const char *rvalue,
 456                 void *data,
 457                 void *userdata) {
 458
 459         unsigned *n = data;
 460         unsigned o;
 461         int r;
 462
 463         assert(filename);
 464         assert(lvalue);
 465         assert(rvalue);
 466         assert(data);
 467
 468         r = safe_atou(rvalue, &o);
 469         if (r < 0) {
 470                 log_syntax(unit, LOG_WARNING, filename, line, r,
 471                            "Failed to parse number of autovts, ignoring: %s", rvalue);
 472                 return 0;
 473         }
 474
 475         if (o > 15) {
 476                 log_syntax(unit, LOG_WARNING, filename, line, 0,
 477                            "A maximum of 15 autovts are supported, ignoring: %s", rvalue);
 478                 return 0;
 479         }
 480
 481         *n = o;
 482         return 0;
 483 }
 484
 485 static int vt_is_busy(unsigned vtnr) {
 486         struct vt_stat vt_stat;
 487         int r;
 488         _cleanup_close_ int fd;
 489
 490         assert(vtnr >= 1);
 491
 492         /* VT_GETSTATE "cannot return state for more than 16 VTs, since v_state is short" */
 493         assert(vtnr <= 15);
 494
 495         /* We explicitly open /dev/tty1 here instead of /dev/tty0. If
 496          * we'd open the latter we'd open the foreground tty which
 497          * hence would be unconditionally busy. By opening /dev/tty1
 498          * we avoid this. Since tty1 is special and needs to be an
 499          * explicitly loaded getty or DM this is safe. */
 500
 501         fd = open_terminal("/dev/tty1", O_RDWR|O_NOCTTY|O_CLOEXEC);
 502         if (fd < 0)
 503                 return -errno;
 504
 505         if (ioctl(fd, VT_GETSTATE, &vt_stat) < 0)
 506                 r = -errno;
 507         else
 508                 r = !!(vt_stat.v_state & (1 << vtnr));
 509
 510         return r;
 511 }
 512
 513 int manager_spawn_autovt(Manager *m, unsigned vtnr) {
 514         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 515         char name[sizeof("autovt@tty.service") + DECIMAL_STR_MAX(unsigned)];
 516         int r;
 517
 518         assert(m);
 519         assert(vtnr >= 1);
 520
 521         if (vtnr > m->n_autovts &&
 522             vtnr != m->reserve_vt)
 523                 return 0;
 524
 525         if (vtnr != m->reserve_vt) {
 526                 /* If this is the reserved TTY, we'll start the getty
 527                  * on it in any case, but otherwise only if it is not
 528                  * busy. */
 529
 530                 r = vt_is_busy(vtnr);
 531                 if (r < 0)
 532                         return r;
 533                 else if (r > 0)
 534                         return -EBUSY;
 535         }
 536
 537         xsprintf(name, "autovt@tty%u.service", vtnr);
 538         r = sd_bus_call_method(
 539                         m->bus,
 540                         "org.freedesktop.systemd1",
 541                         "/org/freedesktop/systemd1",
 542                         "org.freedesktop.systemd1.Manager",
 543                         "StartUnit",
 544                         &error,
 545                         NULL,
 546                         "ss", name, "fail");
 547         if (r < 0)
 548                 return log_error_errno(r, "Failed to start %s: %s", name, bus_error_message(&error, r));
 549
 550         return 0;
 551 }
 552
 553 bool manager_is_lid_closed(Manager *m) {
 554         Button *b;
 555
 556         HASHMAP_FOREACH(b, m->buttons)
 557                 if (b->lid_closed)
 558                         return true;
 559
 560         return false;
 561 }
 562
 563 static bool manager_is_docked(Manager *m) {
 564         Button *b;
 565
 566         HASHMAP_FOREACH(b, m->buttons)
 567                 if (b->docked)
 568                         return true;
 569
 570         return false;
 571 }
 572
 573 static int manager_count_external_displays(Manager *m) {
 574         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 575         sd_device *d;
 576         int r, n = 0;
 577
 578         r = sd_device_enumerator_new(&e);
 579         if (r < 0)
 580                 return r;
 581
 582         r = sd_device_enumerator_allow_uninitialized(e);
 583         if (r < 0)
 584                 return r;
 585
 586         r = sd_device_enumerator_add_match_subsystem(e, "drm", true);
 587         if (r < 0)
 588                 return r;
 589
 590         FOREACH_DEVICE(e, d) {
 591                 const char *status, *enabled, *dash, *nn, *subsys;
 592                 sd_device *p;
 593
 594                 if (sd_device_get_parent(d, &p) < 0)
 595                         continue;
 596
 597                 /* If the parent shares the same subsystem as the
 598                  * device we are looking at then it is a connector,
 599                  * which is what we are interested in. */
 600                 if (sd_device_get_subsystem(p, &subsys) < 0 || !streq(subsys, "drm"))
 601                         continue;
 602
 603                 if (sd_device_get_sysname(d, &nn) < 0)
 604                         continue;
 605
 606                 /* Ignore internal displays: the type is encoded in the sysfs name, as the second dash
 607                  * separated item (the first is the card name, the last the connector number). We implement a
 608                  * deny list of external displays here, rather than an allow list of internal ones, to ensure
 609                  * we don't block suspends too eagerly. */
 610                 dash = strchr(nn, '-');
 611                 if (!dash)
 612                         continue;
 613
 614                 dash++;
 615                 if (!STARTSWITH_SET(dash,
 616                                     "VGA-", "DVI-I-", "DVI-D-", "DVI-A-"
 617                                     "Composite-", "SVIDEO-", "Component-",
 618                                     "DIN-", "DP-", "HDMI-A-", "HDMI-B-", "TV-"))
 619                         continue;
 620
 621                 /* Ignore ports that are not enabled */
 622                 if (sd_device_get_sysattr_value(d, "enabled", &enabled) < 0 || !streq(enabled, "enabled"))
 623                         continue;
 624
 625                 /* We count any connector which is not explicitly
 626                  * "disconnected" as connected. */
 627                 if (sd_device_get_sysattr_value(d, "status", &status) < 0 || !streq(status, "disconnected"))
 628                         n++;
 629         }
 630
 631         return n;
 632 }
 633
 634 bool manager_is_docked_or_external_displays(Manager *m) {
 635         int n;
 636
 637         /* If we are docked don't react to lid closing */
 638         if (manager_is_docked(m)) {
 639                 log_debug("System is docked.");
 640                 return true;
 641         }
 642
 643         /* If we have more than one display connected,
 644          * assume that we are docked. */
 645         n = manager_count_external_displays(m);
 646         if (n < 0)
 647                 log_warning_errno(n, "Display counting failed: %m");
 648         else if (n >= 1) {
 649                 log_debug("External (%i) displays connected.", n);
 650                 return true;
 651         }
 652
 653         return false;
 654 }
 655
 656 bool manager_is_on_external_power(void) {
 657         int r;
 658
 659         /* For now we only check for AC power, but 'external power' can apply to anything that isn't an internal
 660          * battery */
 661         r = on_ac_power();
 662         if (r < 0)
 663                 log_warning_errno(r, "Failed to read AC power status: %m");
 664
 665         return r != 0; /* Treat failure as 'on AC' */
 666 }
 667
 668 bool manager_all_buttons_ignored(Manager *m) {
 669         assert(m);
 670
 671         if (m->handle_power_key != HANDLE_IGNORE)
 672                 return false;
 673         if (m->handle_suspend_key != HANDLE_IGNORE)
 674                 return false;
 675         if (m->handle_hibernate_key != HANDLE_IGNORE)
 676                 return false;
 677         if (m->handle_lid_switch != HANDLE_IGNORE)
 678                 return false;
 679         if (!IN_SET(m->handle_lid_switch_ep, _HANDLE_ACTION_INVALID, HANDLE_IGNORE))
 680                 return false;
 681         if (m->handle_lid_switch_docked != HANDLE_IGNORE)
 682                 return false;
 683         if (m->handle_reboot_key != HANDLE_IGNORE)
 684                 return false;
 685
 686         return true;
 687 }
 688
 689 int manager_read_utmp(Manager *m) {
 690 #if ENABLE_UTMP
 691         int r;
 692         _cleanup_(utxent_cleanup) bool utmpx = false;
 693
 694         assert(m);
 695
 696         if (utmpxname(_PATH_UTMPX) < 0)
 697                 return log_error_errno(errno, "Failed to set utmp path to " _PATH_UTMPX ": %m");
 698
 699         utmpx = utxent_start();
 700
 701         for (;;) {
 702                 _cleanup_free_ char *t = NULL;
 703                 struct utmpx *u;
 704                 const char *c;
 705                 Session *s;
 706
 707                 errno = 0;
 708                 u = getutxent();
 709                 if (!u) {
 710                         if (errno != 0)
 711                                 log_warning_errno(errno, "Failed to read " _PATH_UTMPX ", ignoring: %m");
 712                         return 0;
 713                 }
 714
 715                 if (u->ut_type != USER_PROCESS)
 716                         continue;
 717
 718                 if (!pid_is_valid(u->ut_pid))
 719                         continue;
 720
 721                 t = strndup(u->ut_line, sizeof(u->ut_line));
 722                 if (!t)
 723                         return log_oom();
 724
 725                 c = path_startswith(t, "/dev/");
 726                 if (c) {
 727                         r = free_and_strdup(&t, c);
 728                         if (r < 0)
 729                                 return log_oom();
 730                 }
 731
 732                 if (isempty(t))
 733                         continue;
 734
 735                 s = hashmap_get(m->sessions_by_leader, PID_TO_PTR(u->ut_pid));
 736                 if (!s)
 737                         continue;
 738
 739                 if (s->tty_validity == TTY_FROM_UTMP && !streq_ptr(s->tty, t)) {
 740                         /* This may happen on multiplexed SSH connection (i.e. 'SSH connection sharing'). In
 741                          * this case PAM and utmp sessions don't match. In such a case let's invalidate the TTY
 742                          * information and never acquire it again. */
 743
 744                         s->tty = mfree(s->tty);
 745                         s->tty_validity = TTY_UTMP_INCONSISTENT;
 746                         log_debug("Session '%s' has inconsistent TTY information, dropping TTY information.", s->id);
 747                         continue;
 748                 }
 749
 750                 /* Never override what we figured out once */
 751                 if (s->tty || s->tty_validity >= 0)
 752                         continue;
 753
 754                 s->tty = TAKE_PTR(t);
 755                 s->tty_validity = TTY_FROM_UTMP;
 756                 log_debug("Acquired TTY information '%s' from utmp for session '%s'.", s->tty, s->id);
 757         }
 758
 759 #else
 760         return 0;
 761 #endif
 762 }
 763
 764 #if ENABLE_UTMP
 765 static int manager_dispatch_utmp(sd_event_source *s, const struct inotify_event *event, void *userdata) {
 766         Manager *m = userdata;
 767
 768         assert(m);
 769
 770         /* If there's indication the file itself might have been removed or became otherwise unavailable, then let's
 771          * reestablish the watch on whatever there's now. */
 772         if ((event->mask & (IN_ATTRIB|IN_DELETE_SELF|IN_MOVE_SELF|IN_Q_OVERFLOW|IN_UNMOUNT)) != 0)
 773                 manager_connect_utmp(m);
 774
 775         (void) manager_read_utmp(m);
 776         return 0;
 777 }
 778 #endif
 779
 780 void manager_connect_utmp(Manager *m) {
 781 #if ENABLE_UTMP
 782         sd_event_source *s = NULL;
 783         int r;
 784
 785         assert(m);
 786
 787         /* Watch utmp for changes via inotify. We do this to deal with tools such as ssh, which will register the PAM
 788          * session early, and acquire a TTY only much later for the connection. Thus during PAM the TTY won't be known
 789          * yet. ssh will register itself with utmp when it finally acquired the TTY. Hence, let's make use of this, and
 790          * watch utmp for the TTY asynchronously. We use the PAM session's leader PID as key, to find the right entry.
 791          *
 792          * Yes, relying on utmp is pretty ugly, but it's good enough for informational purposes, as well as idle
 793          * detection (which, for tty sessions, relies on the TTY used) */
 794
 795         r = sd_event_add_inotify(m->event, &s, _PATH_UTMPX, IN_MODIFY|IN_MOVE_SELF|IN_DELETE_SELF|IN_ATTRIB, manager_dispatch_utmp, m);
 796         if (r < 0)
 797                 log_full_errno(r == -ENOENT ? LOG_DEBUG: LOG_WARNING, r, "Failed to create inotify watch on " _PATH_UTMPX ", ignoring: %m");
 798         else {
 799                 r = sd_event_source_set_priority(s, SD_EVENT_PRIORITY_IDLE);
 800                 if (r < 0)
 801                         log_warning_errno(r, "Failed to adjust utmp event source priority, ignoring: %m");
 802
 803                 (void) sd_event_source_set_description(s, "utmp");
 804         }
 805
 806         sd_event_source_unref(m->utmp_event_source);
 807         m->utmp_event_source = s;
 808 #endif
 809 }
 810
 811 void manager_reconnect_utmp(Manager *m) {
 812 #if ENABLE_UTMP
 813         assert(m);
 814
 815         if (m->utmp_event_source)
 816                 return;
 817
 818         manager_connect_utmp(m);
 819 #endif
 820 }
 821
 822 int manager_read_efi_boot_loader_entries(Manager *m) {
 823 #if ENABLE_EFI
 824         int r;
 825
 826         assert(m);
 827         if (m->efi_boot_loader_entries_set)
 828                 return 0;
 829
 830         r = efi_loader_get_entries(&m->efi_boot_loader_entries);
 831         if (r == -ENOENT || ERRNO_IS_NOT_SUPPORTED(r)) {
 832                 log_debug_errno(r, "Boot loader reported no entries.");
 833                 m->efi_boot_loader_entries_set = true;
 834                 return 0;
 835         }
 836         if (r < 0)
 837                 return log_error_errno(r, "Failed to determine entries reported by boot loader: %m");
 838
 839         m->efi_boot_loader_entries_set = true;
 840         return 1;
 841 #else
 842         return 0;
 843 #endif
 844 }