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