src/manager.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <assert.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <sys/epoll.h>
  26 #include <signal.h>
  27 #include <sys/signalfd.h>
  28 #include <sys/wait.h>
  29 #include <unistd.h>
  30 #include <utmpx.h>
  31 #include <sys/poll.h>
  32 #include <sys/reboot.h>
  33 #include <sys/ioctl.h>
  34 #include <linux/kd.h>
  35 #include <termios.h>
  36 #include <fcntl.h>
  37 #include <sys/types.h>
  38 #include <sys/stat.h>
  39 #include <dirent.h>
  40
  41 #include "manager.h"
  42 #include "hashmap.h"
  43 #include "macro.h"
  44 #include "strv.h"
  45 #include "log.h"
  46 #include "util.h"
  47 #include "ratelimit.h"
  48 #include "cgroup.h"
  49 #include "mount-setup.h"
  50 #include "utmp-wtmp.h"
  51 #include "unit-name.h"
  52 #include "dbus-unit.h"
  53 #include "dbus-job.h"
  54 #include "missing.h"
  55 #include "path-lookup.h"
  56 #include "special.h"
  57 #include "bus-errors.h"
  58
  59 /* As soon as 16 units are in our GC queue, make sure to run a gc sweep */
  60 #define GC_QUEUE_ENTRIES_MAX 16
  61
  62 /* As soon as 5s passed since a unit was added to our GC queue, make sure to run a gc sweep */
  63 #define GC_QUEUE_USEC_MAX (10*USEC_PER_SEC)
  64
  65 /* Where clients shall send notification messages to */
  66 #define NOTIFY_SOCKET "/org/freedesktop/systemd1/notify"
  67
  68 static int manager_setup_notify(Manager *m) {
  69         union {
  70                 struct sockaddr sa;
  71                 struct sockaddr_un un;
  72         } sa;
  73         struct epoll_event ev;
  74         int one = 1;
  75
  76         assert(m);
  77
  78         m->notify_watch.type = WATCH_NOTIFY;
  79         if ((m->notify_watch.fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) {
  80                 log_error("Failed to allocate notification socket: %m");
  81                 return -errno;
  82         }
  83
  84         zero(sa);
  85         sa.sa.sa_family = AF_UNIX;
  86
  87         if (getpid() != 1)
  88                 snprintf(sa.un.sun_path+1, sizeof(sa.un.sun_path)-1, NOTIFY_SOCKET "/%llu", random_ull());
  89         else
  90                 strncpy(sa.un.sun_path+1, NOTIFY_SOCKET, sizeof(sa.un.sun_path)-1);
  91
  92         if (bind(m->notify_watch.fd, &sa.sa, sizeof(sa)) < 0) {
  93                 log_error("bind() failed: %m");
  94                 return -errno;
  95         }
  96
  97         if (setsockopt(m->notify_watch.fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)) < 0) {
  98                 log_error("SO_PASSCRED failed: %m");
  99                 return -errno;
 100         }
 101
 102         zero(ev);
 103         ev.events = EPOLLIN;
 104         ev.data.ptr = &m->notify_watch;
 105
 106         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->notify_watch.fd, &ev) < 0)
 107                 return -errno;
 108
 109         if (!(m->notify_socket = strdup(sa.un.sun_path+1)))
 110                 return -ENOMEM;
 111
 112         return 0;
 113 }
 114
 115 static int enable_special_signals(Manager *m) {
 116         char fd;
 117
 118         assert(m);
 119
 120         /* Enable that we get SIGINT on control-alt-del */
 121         if (reboot(RB_DISABLE_CAD) < 0)
 122                 log_warning("Failed to enable ctrl-alt-del handling: %m");
 123
 124         if ((fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY)) < 0)
 125                 log_warning("Failed to open /dev/tty0: %m");
 126         else {
 127                 /* Enable that we get SIGWINCH on kbrequest */
 128                 if (ioctl(fd, KDSIGACCEPT, SIGWINCH) < 0)
 129                         log_warning("Failed to enable kbrequest handling: %s", strerror(errno));
 130
 131                 close_nointr_nofail(fd);
 132         }
 133
 134         return 0;
 135 }
 136
 137 static int manager_setup_signals(Manager *m) {
 138         sigset_t mask;
 139         struct epoll_event ev;
 140         struct sigaction sa;
 141
 142         assert(m);
 143
 144         /* We are not interested in SIGSTOP and friends. */
 145         zero(sa);
 146         sa.sa_handler = SIG_DFL;
 147         sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
 148         assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
 149
 150         assert_se(sigemptyset(&mask) == 0);
 151
 152         sigset_add_many(&mask,
 153                         SIGCHLD,     /* Child died */
 154                         SIGTERM,     /* Reexecute daemon */
 155                         SIGHUP,      /* Reload configuration */
 156                         SIGUSR1,     /* systemd/upstart: reconnect to D-Bus */
 157                         SIGUSR2,     /* systemd: dump status */
 158                         SIGINT,      /* Kernel sends us this on control-alt-del */
 159                         SIGWINCH,    /* Kernel sends us this on kbrequest (alt-arrowup) */
 160                         SIGPWR,      /* Some kernel drivers and upsd send us this on power failure */
 161                         SIGRTMIN+0,  /* systemd: start default.target */
 162                         SIGRTMIN+1,  /* systemd: start rescue.target */
 163                         SIGRTMIN+2,  /* systemd: isolate emergency.target */
 164                         SIGRTMIN+3,  /* systemd: start halt.target */
 165                         SIGRTMIN+4,  /* systemd: start poweroff.target */
 166                         SIGRTMIN+5,  /* systemd: start reboot.target */
 167                         -1);
 168         assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
 169
 170         m->signal_watch.type = WATCH_SIGNAL;
 171         if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0)
 172                 return -errno;
 173
 174         zero(ev);
 175         ev.events = EPOLLIN;
 176         ev.data.ptr = &m->signal_watch;
 177
 178         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0)
 179                 return -errno;
 180
 181         if (m->running_as == MANAGER_SYSTEM)
 182                 return enable_special_signals(m);
 183
 184         return 0;
 185 }
 186
 187 int manager_new(ManagerRunningAs running_as, Manager **_m) {
 188         Manager *m;
 189         int r = -ENOMEM;
 190
 191         assert(_m);
 192         assert(running_as >= 0);
 193         assert(running_as < _MANAGER_RUNNING_AS_MAX);
 194
 195         if (!(m = new0(Manager, 1)))
 196                 return -ENOMEM;
 197
 198         dual_timestamp_get(&m->startup_timestamp);
 199
 200         m->running_as = running_as;
 201         m->name_data_slot = m->subscribed_data_slot = -1;
 202         m->exit_code = _MANAGER_EXIT_CODE_INVALID;
 203         m->pin_cgroupfs_fd = -1;
 204
 205         m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_fd = -1;
 206         m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */
 207
 208         if (!(m->environment = strv_copy(environ)))
 209                 goto fail;
 210
 211         if (!(m->units = hashmap_new(string_hash_func, string_compare_func)))
 212                 goto fail;
 213
 214         if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 215                 goto fail;
 216
 217         if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 218                 goto fail;
 219
 220         if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
 221                 goto fail;
 222
 223         if (!(m->cgroup_bondings = hashmap_new(string_hash_func, string_compare_func)))
 224                 goto fail;
 225
 226         if (!(m->watch_bus = hashmap_new(string_hash_func, string_compare_func)))
 227                 goto fail;
 228
 229         if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
 230                 goto fail;
 231
 232         if ((r = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
 233                 goto fail;
 234
 235         if ((r = manager_setup_signals(m)) < 0)
 236                 goto fail;
 237
 238         if ((r = manager_setup_cgroup(m)) < 0)
 239                 goto fail;
 240
 241         if ((r = manager_setup_notify(m)) < 0)
 242                 goto fail;
 243
 244         /* Try to connect to the busses, if possible. */
 245         if ((r = bus_init(m)) < 0)
 246                 goto fail;
 247
 248         *_m = m;
 249         return 0;
 250
 251 fail:
 252         manager_free(m);
 253         return r;
 254 }
 255
 256 static unsigned manager_dispatch_cleanup_queue(Manager *m) {
 257         Meta *meta;
 258         unsigned n = 0;
 259
 260         assert(m);
 261
 262         while ((meta = m->cleanup_queue)) {
 263                 assert(meta->in_cleanup_queue);
 264
 265                 unit_free((Unit*) meta);
 266                 n++;
 267         }
 268
 269         return n;
 270 }
 271
 272 enum {
 273         GC_OFFSET_IN_PATH,  /* This one is on the path we were travelling */
 274         GC_OFFSET_UNSURE,   /* No clue */
 275         GC_OFFSET_GOOD,     /* We still need this unit */
 276         GC_OFFSET_BAD,      /* We don't need this unit anymore */
 277         _GC_OFFSET_MAX
 278 };
 279
 280 static void unit_gc_sweep(Unit *u, unsigned gc_marker) {
 281         Iterator i;
 282         Unit *other;
 283         bool is_bad;
 284
 285         assert(u);
 286
 287         if (u->meta.gc_marker == gc_marker + GC_OFFSET_GOOD ||
 288             u->meta.gc_marker == gc_marker + GC_OFFSET_BAD ||
 289             u->meta.gc_marker == gc_marker + GC_OFFSET_IN_PATH)
 290                 return;
 291
 292         if (u->meta.in_cleanup_queue)
 293                 goto bad;
 294
 295         if (unit_check_gc(u))
 296                 goto good;
 297
 298         u->meta.gc_marker = gc_marker + GC_OFFSET_IN_PATH;
 299
 300         is_bad = true;
 301
 302         SET_FOREACH(other, u->meta.dependencies[UNIT_REFERENCED_BY], i) {
 303                 unit_gc_sweep(other, gc_marker);
 304
 305                 if (other->meta.gc_marker == gc_marker + GC_OFFSET_GOOD)
 306                         goto good;
 307
 308                 if (other->meta.gc_marker != gc_marker + GC_OFFSET_BAD)
 309                         is_bad = false;
 310         }
 311
 312         if (is_bad)
 313                 goto bad;
 314
 315         /* We were unable to find anything out about this entry, so
 316          * let's investigate it later */
 317         u->meta.gc_marker = gc_marker + GC_OFFSET_UNSURE;
 318         unit_add_to_gc_queue(u);
 319         return;
 320
 321 bad:
 322         /* We definitely know that this one is not useful anymore, so
 323          * let's mark it for deletion */
 324         u->meta.gc_marker = gc_marker + GC_OFFSET_BAD;
 325         unit_add_to_cleanup_queue(u);
 326         return;
 327
 328 good:
 329         u->meta.gc_marker = gc_marker + GC_OFFSET_GOOD;
 330 }
 331
 332 static unsigned manager_dispatch_gc_queue(Manager *m) {
 333         Meta *meta;
 334         unsigned n = 0;
 335         unsigned gc_marker;
 336
 337         assert(m);
 338
 339         if ((m->n_in_gc_queue < GC_QUEUE_ENTRIES_MAX) &&
 340             (m->gc_queue_timestamp <= 0 ||
 341              (m->gc_queue_timestamp + GC_QUEUE_USEC_MAX) > now(CLOCK_MONOTONIC)))
 342                 return 0;
 343
 344         log_debug("Running GC...");
 345
 346         m->gc_marker += _GC_OFFSET_MAX;
 347         if (m->gc_marker + _GC_OFFSET_MAX <= _GC_OFFSET_MAX)
 348                 m->gc_marker = 1;
 349
 350         gc_marker = m->gc_marker;
 351
 352         while ((meta = m->gc_queue)) {
 353                 assert(meta->in_gc_queue);
 354
 355                 unit_gc_sweep((Unit*) meta, gc_marker);
 356
 357                 LIST_REMOVE(Meta, gc_queue, m->gc_queue, meta);
 358                 meta->in_gc_queue = false;
 359
 360                 n++;
 361
 362                 if (meta->gc_marker == gc_marker + GC_OFFSET_BAD ||
 363                     meta->gc_marker == gc_marker + GC_OFFSET_UNSURE) {
 364                         log_debug("Collecting %s", meta->id);
 365                         meta->gc_marker = gc_marker + GC_OFFSET_BAD;
 366                         unit_add_to_cleanup_queue((Unit*) meta);
 367                 }
 368         }
 369
 370         m->n_in_gc_queue = 0;
 371         m->gc_queue_timestamp = 0;
 372
 373         return n;
 374 }
 375
 376 static void manager_clear_jobs_and_units(Manager *m) {
 377         Job *j;
 378         Unit *u;
 379
 380         assert(m);
 381
 382         while ((j = hashmap_first(m->transaction_jobs)))
 383                 job_free(j);
 384
 385         while ((u = hashmap_first(m->units)))
 386                 unit_free(u);
 387
 388         manager_dispatch_cleanup_queue(m);
 389
 390         assert(!m->load_queue);
 391         assert(!m->run_queue);
 392         assert(!m->dbus_unit_queue);
 393         assert(!m->dbus_job_queue);
 394         assert(!m->cleanup_queue);
 395         assert(!m->gc_queue);
 396
 397         assert(hashmap_isempty(m->transaction_jobs));
 398         assert(hashmap_isempty(m->jobs));
 399         assert(hashmap_isempty(m->units));
 400 }
 401
 402 void manager_free(Manager *m) {
 403         UnitType c;
 404
 405         assert(m);
 406
 407         manager_clear_jobs_and_units(m);
 408
 409         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 410                 if (unit_vtable[c]->shutdown)
 411                         unit_vtable[c]->shutdown(m);
 412
 413         /* If we reexecute ourselves, we keep the root cgroup
 414          * around */
 415         manager_shutdown_cgroup(m, m->exit_code != MANAGER_REEXECUTE);
 416
 417         bus_done(m);
 418
 419         hashmap_free(m->units);
 420         hashmap_free(m->jobs);
 421         hashmap_free(m->transaction_jobs);
 422         hashmap_free(m->watch_pids);
 423         hashmap_free(m->watch_bus);
 424
 425         if (m->epoll_fd >= 0)
 426                 close_nointr_nofail(m->epoll_fd);
 427         if (m->signal_watch.fd >= 0)
 428                 close_nointr_nofail(m->signal_watch.fd);
 429         if (m->notify_watch.fd >= 0)
 430                 close_nointr_nofail(m->notify_watch.fd);
 431
 432         free(m->notify_socket);
 433
 434         lookup_paths_free(&m->lookup_paths);
 435         strv_free(m->environment);
 436
 437         hashmap_free(m->cgroup_bondings);
 438         set_free_free(m->unit_path_cache);
 439
 440         free(m);
 441 }
 442
 443 int manager_enumerate(Manager *m) {
 444         int r = 0, q;
 445         UnitType c;
 446
 447         assert(m);
 448
 449         /* Let's ask every type to load all units from disk/kernel
 450          * that it might know */
 451         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 452                 if (unit_vtable[c]->enumerate)
 453                         if ((q = unit_vtable[c]->enumerate(m)) < 0)
 454                                 r = q;
 455
 456         manager_dispatch_load_queue(m);
 457         return r;
 458 }
 459
 460 int manager_coldplug(Manager *m) {
 461         int r = 0, q;
 462         Iterator i;
 463         Unit *u;
 464         char *k;
 465
 466         assert(m);
 467
 468         /* Then, let's set up their initial state. */
 469         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
 470
 471                 /* ignore aliases */
 472                 if (u->meta.id != k)
 473                         continue;
 474
 475                 if ((q = unit_coldplug(u)) < 0)
 476                         r = q;
 477         }
 478
 479         return r;
 480 }
 481
 482 static void manager_build_unit_path_cache(Manager *m) {
 483         char **i;
 484         DIR *d = NULL;
 485         int r;
 486
 487         assert(m);
 488
 489         set_free_free(m->unit_path_cache);
 490
 491         if (!(m->unit_path_cache = set_new(string_hash_func, string_compare_func))) {
 492                 log_error("Failed to allocate unit path cache.");
 493                 return;
 494         }
 495
 496         /* This simply builds a list of files we know exist, so that
 497          * we don't always have to go to disk */
 498
 499         STRV_FOREACH(i, m->lookup_paths.unit_path) {
 500                 struct dirent *de;
 501
 502                 if (!(d = opendir(*i))) {
 503                         log_error("Failed to open directory: %m");
 504                         continue;
 505                 }
 506
 507                 while ((de = readdir(d))) {
 508                         char *p;
 509
 510                         if (ignore_file(de->d_name))
 511                                 continue;
 512
 513                         if (asprintf(&p, "%s/%s", streq(*i, "/") ? "" : *i, de->d_name) < 0) {
 514                                 r = -ENOMEM;
 515                                 goto fail;
 516                         }
 517
 518                         if ((r = set_put(m->unit_path_cache, p)) < 0) {
 519                                 free(p);
 520                                 goto fail;
 521                         }
 522                 }
 523
 524                 closedir(d);
 525                 d = NULL;
 526         }
 527
 528         return;
 529
 530 fail:
 531         log_error("Failed to build unit path cache: %s", strerror(-r));
 532
 533         set_free_free(m->unit_path_cache);
 534         m->unit_path_cache = NULL;
 535
 536         if (d)
 537                 closedir(d);
 538 }
 539
 540 int manager_startup(Manager *m, FILE *serialization, FDSet *fds) {
 541         int r, q;
 542
 543         assert(m);
 544
 545         manager_build_unit_path_cache(m);
 546
 547         /* First, enumerate what we can from all config files */
 548         r = manager_enumerate(m);
 549
 550         /* Second, deserialize if there is something to deserialize */
 551         if (serialization)
 552                 if ((q = manager_deserialize(m, serialization, fds)) < 0)
 553                         r = q;
 554
 555         /* Third, fire things up! */
 556         if ((q = manager_coldplug(m)) < 0)
 557                 r = q;
 558
 559         /* Now that the initial devices are available, let's see if we
 560          * can write the utmp file */
 561         manager_write_utmp_reboot(m);
 562
 563         return r;
 564 }
 565
 566 static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) {
 567         assert(m);
 568         assert(j);
 569
 570         /* Deletes one job from the transaction */
 571
 572         manager_transaction_unlink_job(m, j, delete_dependencies);
 573
 574         if (!j->installed)
 575                 job_free(j);
 576 }
 577
 578 static void transaction_delete_unit(Manager *m, Unit *u) {
 579         Job *j;
 580
 581         /* Deletes all jobs associated with a certain unit from the
 582          * transaction */
 583
 584         while ((j = hashmap_get(m->transaction_jobs, u)))
 585                 transaction_delete_job(m, j, true);
 586 }
 587
 588 static void transaction_clean_dependencies(Manager *m) {
 589         Iterator i;
 590         Job *j;
 591
 592         assert(m);
 593
 594         /* Drops all dependencies of all installed jobs */
 595
 596         HASHMAP_FOREACH(j, m->jobs, i) {
 597                 while (j->subject_list)
 598                         job_dependency_free(j->subject_list);
 599                 while (j->object_list)
 600                         job_dependency_free(j->object_list);
 601         }
 602
 603         assert(!m->transaction_anchor);
 604 }
 605
 606 static void transaction_abort(Manager *m) {
 607         Job *j;
 608
 609         assert(m);
 610
 611         while ((j = hashmap_first(m->transaction_jobs)))
 612                 if (j->installed)
 613                         transaction_delete_job(m, j, true);
 614                 else
 615                         job_free(j);
 616
 617         assert(hashmap_isempty(m->transaction_jobs));
 618
 619         transaction_clean_dependencies(m);
 620 }
 621
 622 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
 623         JobDependency *l;
 624
 625         assert(m);
 626
 627         /* A recursive sweep through the graph that marks all units
 628          * that matter to the anchor job, i.e. are directly or
 629          * indirectly a dependency of the anchor job via paths that
 630          * are fully marked as mattering. */
 631
 632         if (j)
 633                 l = j->subject_list;
 634         else
 635                 l = m->transaction_anchor;
 636
 637         LIST_FOREACH(subject, l, l) {
 638
 639                 /* This link does not matter */
 640                 if (!l->matters)
 641                         continue;
 642
 643                 /* This unit has already been marked */
 644                 if (l->object->generation == generation)
 645                         continue;
 646
 647                 l->object->matters_to_anchor = true;
 648                 l->object->generation = generation;
 649
 650                 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
 651         }
 652 }
 653
 654 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
 655         JobDependency *l, *last;
 656
 657         assert(j);
 658         assert(other);
 659         assert(j->unit == other->unit);
 660         assert(!j->installed);
 661
 662         /* Merges 'other' into 'j' and then deletes j. */
 663
 664         j->type = t;
 665         j->state = JOB_WAITING;
 666         j->override = j->override || other->override;
 667
 668         j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
 669
 670         /* Patch us in as new owner of the JobDependency objects */
 671         last = NULL;
 672         LIST_FOREACH(subject, l, other->subject_list) {
 673                 assert(l->subject == other);
 674                 l->subject = j;
 675                 last = l;
 676         }
 677
 678         /* Merge both lists */
 679         if (last) {
 680                 last->subject_next = j->subject_list;
 681                 if (j->subject_list)
 682                         j->subject_list->subject_prev = last;
 683                 j->subject_list = other->subject_list;
 684         }
 685
 686         /* Patch us in as new owner of the JobDependency objects */
 687         last = NULL;
 688         LIST_FOREACH(object, l, other->object_list) {
 689                 assert(l->object == other);
 690                 l->object = j;
 691                 last = l;
 692         }
 693
 694         /* Merge both lists */
 695         if (last) {
 696                 last->object_next = j->object_list;
 697                 if (j->object_list)
 698                         j->object_list->object_prev = last;
 699                 j->object_list = other->object_list;
 700         }
 701
 702         /* Kill the other job */
 703         other->subject_list = NULL;
 704         other->object_list = NULL;
 705         transaction_delete_job(m, other, true);
 706 }
 707
 708 static int delete_one_unmergeable_job(Manager *m, Job *j) {
 709         Job *k;
 710
 711         assert(j);
 712
 713         /* Tries to delete one item in the linked list
 714          * j->transaction_next->transaction_next->... that conflicts
 715          * whith another one, in an attempt to make an inconsistent
 716          * transaction work. */
 717
 718         /* We rely here on the fact that if a merged with b does not
 719          * merge with c, either a or b merge with c neither */
 720         LIST_FOREACH(transaction, j, j)
 721                 LIST_FOREACH(transaction, k, j->transaction_next) {
 722                         Job *d;
 723
 724                         /* Is this one mergeable? Then skip it */
 725                         if (job_type_is_mergeable(j->type, k->type))
 726                                 continue;
 727
 728                         /* Ok, we found two that conflict, let's see if we can
 729                          * drop one of them */
 730                         if (!j->matters_to_anchor)
 731                                 d = j;
 732                         else if (!k->matters_to_anchor)
 733                                 d = k;
 734                         else
 735                                 return -ENOEXEC;
 736
 737                         /* Ok, we can drop one, so let's do so. */
 738                         log_notice("Trying to fix job merging by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type));
 739                         transaction_delete_job(m, d, true);
 740                         return 0;
 741                 }
 742
 743         return -EINVAL;
 744 }
 745
 746 static int transaction_merge_jobs(Manager *m, DBusError *e) {
 747         Job *j;
 748         Iterator i;
 749         int r;
 750
 751         assert(m);
 752
 753         /* First step, check whether any of the jobs for one specific
 754          * task conflict. If so, try to drop one of them. */
 755         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 756                 JobType t;
 757                 Job *k;
 758
 759                 t = j->type;
 760                 LIST_FOREACH(transaction, k, j->transaction_next) {
 761                         if ((r = job_type_merge(&t, k->type)) >= 0)
 762                                 continue;
 763
 764                         /* OK, we could not merge all jobs for this
 765                          * action. Let's see if we can get rid of one
 766                          * of them */
 767
 768                         if ((r = delete_one_unmergeable_job(m, j)) >= 0)
 769                                 /* Ok, we managed to drop one, now
 770                                  * let's ask our callers to call us
 771                                  * again after garbage collecting */
 772                                 return -EAGAIN;
 773
 774                         /* We couldn't merge anything. Failure */
 775                         dbus_set_error(e, BUS_ERROR_TRANSACTION_JOBS_CONFLICTING, "Transaction contains conflicting jobs '%s' and '%s' for %s. Probably contradicting requirement dependencies configured.",
 776                                        job_type_to_string(t), job_type_to_string(k->type), k->unit->meta.id);
 777                         return r;
 778                 }
 779         }
 780
 781         /* Second step, merge the jobs. */
 782         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 783                 JobType t = j->type;
 784                 Job *k;
 785
 786                 /* Merge all transactions */
 787                 LIST_FOREACH(transaction, k, j->transaction_next)
 788                         assert_se(job_type_merge(&t, k->type) == 0);
 789
 790                 /* If an active job is mergeable, merge it too */
 791                 if (j->unit->meta.job)
 792                         job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
 793
 794                 while ((k = j->transaction_next)) {
 795                         if (j->installed) {
 796                                 transaction_merge_and_delete_job(m, k, j, t);
 797                                 j = k;
 798                         } else
 799                                 transaction_merge_and_delete_job(m, j, k, t);
 800                 }
 801
 802                 assert(!j->transaction_next);
 803                 assert(!j->transaction_prev);
 804         }
 805
 806         return 0;
 807 }
 808
 809 static void transaction_drop_redundant(Manager *m) {
 810         bool again;
 811
 812         assert(m);
 813
 814         /* Goes through the transaction and removes all jobs that are
 815          * a noop */
 816
 817         do {
 818                 Job *j;
 819                 Iterator i;
 820
 821                 again = false;
 822
 823                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 824                         bool changes_something = false;
 825                         Job *k;
 826
 827                         LIST_FOREACH(transaction, k, j) {
 828
 829                                 if (!job_is_anchor(k) &&
 830                                     job_type_is_redundant(k->type, unit_active_state(k->unit)))
 831                                         continue;
 832
 833                                 changes_something = true;
 834                                 break;
 835                         }
 836
 837                         if (changes_something)
 838                                 continue;
 839
 840                         log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type));
 841                         transaction_delete_job(m, j, false);
 842                         again = true;
 843                         break;
 844                 }
 845
 846         } while (again);
 847 }
 848
 849 static bool unit_matters_to_anchor(Unit *u, Job *j) {
 850         assert(u);
 851         assert(!j->transaction_prev);
 852
 853         /* Checks whether at least one of the jobs for this unit
 854          * matters to the anchor. */
 855
 856         LIST_FOREACH(transaction, j, j)
 857                 if (j->matters_to_anchor)
 858                         return true;
 859
 860         return false;
 861 }
 862
 863 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation, DBusError *e) {
 864         Iterator i;
 865         Unit *u;
 866         int r;
 867
 868         assert(m);
 869         assert(j);
 870         assert(!j->transaction_prev);
 871
 872         /* Does a recursive sweep through the ordering graph, looking
 873          * for a cycle. If we find cycle we try to break it. */
 874
 875         /* Have we seen this before? */
 876         if (j->generation == generation) {
 877                 Job *k;
 878
 879                 /* If the marker is NULL we have been here already and
 880                  * decided the job was loop-free from here. Hence
 881                  * shortcut things and return right-away. */
 882                 if (!j->marker)
 883                         return 0;
 884
 885                 /* So, the marker is not NULL and we already have been
 886                  * here. We have a cycle. Let's try to break it. We go
 887                  * backwards in our path and try to find a suitable
 888                  * job to remove. We use the marker to find our way
 889                  * back, since smart how we are we stored our way back
 890                  * in there. */
 891                 log_warning("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type));
 892
 893                 for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) {
 894
 895                         log_info("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 896
 897                         if (!k->installed &&
 898                             !unit_matters_to_anchor(k->unit, k)) {
 899                                 /* Ok, we can drop this one, so let's
 900                                  * do so. */
 901                                 log_warning("Breaking order cycle by deleting job %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 902                                 transaction_delete_unit(m, k->unit);
 903                                 return -EAGAIN;
 904                         }
 905
 906                         /* Check if this in fact was the beginning of
 907                          * the cycle */
 908                         if (k == j)
 909                                 break;
 910                 }
 911
 912                 log_error("Unable to break cycle");
 913
 914                 dbus_set_error(e, BUS_ERROR_TRANSACTION_ORDER_IS_CYCLIC, "Transaction order is cyclic. See logs for details.");
 915                 return -ENOEXEC;
 916         }
 917
 918         /* Make the marker point to where we come from, so that we can
 919          * find our way backwards if we want to break a cycle. We use
 920          * a special marker for the beginning: we point to
 921          * ourselves. */
 922         j->marker = from ? from : j;
 923         j->generation = generation;
 924
 925         /* We assume that the the dependencies are bidirectional, and
 926          * hence can ignore UNIT_AFTER */
 927         SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
 928                 Job *o;
 929
 930                 /* Is there a job for this unit? */
 931                 if (!(o = hashmap_get(m->transaction_jobs, u)))
 932
 933                         /* Ok, there is no job for this in the
 934                          * transaction, but maybe there is already one
 935                          * running? */
 936                         if (!(o = u->meta.job))
 937                                 continue;
 938
 939                 if ((r = transaction_verify_order_one(m, o, j, generation, e)) < 0)
 940                         return r;
 941         }
 942
 943         /* Ok, let's backtrack, and remember that this entry is not on
 944          * our path anymore. */
 945         j->marker = NULL;
 946
 947         return 0;
 948 }
 949
 950 static int transaction_verify_order(Manager *m, unsigned *generation, DBusError *e) {
 951         Job *j;
 952         int r;
 953         Iterator i;
 954         unsigned g;
 955
 956         assert(m);
 957         assert(generation);
 958
 959         /* Check if the ordering graph is cyclic. If it is, try to fix
 960          * that up by dropping one of the jobs. */
 961
 962         g = (*generation)++;
 963
 964         HASHMAP_FOREACH(j, m->transaction_jobs, i)
 965                 if ((r = transaction_verify_order_one(m, j, NULL, g, e)) < 0)
 966                         return r;
 967
 968         return 0;
 969 }
 970
 971 static void transaction_collect_garbage(Manager *m) {
 972         bool again;
 973
 974         assert(m);
 975
 976         /* Drop jobs that are not required by any other job */
 977
 978         do {
 979                 Iterator i;
 980                 Job *j;
 981
 982                 again = false;
 983
 984                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 985                         if (j->object_list)
 986                                 continue;
 987
 988                         log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type));
 989                         transaction_delete_job(m, j, true);
 990                         again = true;
 991                         break;
 992                 }
 993
 994         } while (again);
 995 }
 996
 997 static int transaction_is_destructive(Manager *m, DBusError *e) {
 998         Iterator i;
 999         Job *j;
1000
1001         assert(m);
1002
1003         /* Checks whether applying this transaction means that
1004          * existing jobs would be replaced */
1005
1006         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1007
1008                 /* Assume merged */
1009                 assert(!j->transaction_prev);
1010                 assert(!j->transaction_next);
1011
1012                 if (j->unit->meta.job &&
1013                     j->unit->meta.job != j &&
1014                     !job_type_is_superset(j->type, j->unit->meta.job->type)) {
1015
1016                         dbus_set_error(e, BUS_ERROR_TRANSACTION_IS_DESTRUCTIVE, "Transaction is destructive.");
1017                         return -EEXIST;
1018                 }
1019         }
1020
1021         return 0;
1022 }
1023
1024 static void transaction_minimize_impact(Manager *m) {
1025         bool again;
1026         assert(m);
1027
1028         /* Drops all unnecessary jobs that reverse already active jobs
1029          * or that stop a running service. */
1030
1031         do {
1032                 Job *j;
1033                 Iterator i;
1034
1035                 again = false;
1036
1037                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1038                         LIST_FOREACH(transaction, j, j) {
1039                                 bool stops_running_service, changes_existing_job;
1040
1041                                 /* If it matters, we shouldn't drop it */
1042                                 if (j->matters_to_anchor)
1043                                         continue;
1044
1045                                 /* Would this stop a running service?
1046                                  * Would this change an existing job?
1047                                  * If so, let's drop this entry */
1048
1049                                 stops_running_service =
1050                                         j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
1051
1052                                 changes_existing_job =
1053                                         j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->state);
1054
1055                                 if (!stops_running_service && !changes_existing_job)
1056                                         continue;
1057
1058                                 if (stops_running_service)
1059                                         log_info("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type));
1060
1061                                 if (changes_existing_job)
1062                                         log_info("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type));
1063
1064                                 /* Ok, let's get rid of this */
1065                                 log_info("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type));
1066
1067                                 transaction_delete_job(m, j, true);
1068                                 again = true;
1069                                 break;
1070                         }
1071
1072                         if (again)
1073                                 break;
1074                 }
1075
1076         } while (again);
1077 }
1078
1079 static int transaction_apply(Manager *m) {
1080         Iterator i;
1081         Job *j;
1082         int r;
1083
1084         /* Moves the transaction jobs to the set of active jobs */
1085
1086         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1087                 /* Assume merged */
1088                 assert(!j->transaction_prev);
1089                 assert(!j->transaction_next);
1090
1091                 if (j->installed)
1092                         continue;
1093
1094                 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
1095                         goto rollback;
1096         }
1097
1098         while ((j = hashmap_steal_first(m->transaction_jobs))) {
1099                 if (j->installed)
1100                         continue;
1101
1102                 if (j->unit->meta.job)
1103                         job_free(j->unit->meta.job);
1104
1105                 j->unit->meta.job = j;
1106                 j->installed = true;
1107
1108                 /* We're fully installed. Now let's free data we don't
1109                  * need anymore. */
1110
1111                 assert(!j->transaction_next);
1112                 assert(!j->transaction_prev);
1113
1114                 job_add_to_run_queue(j);
1115                 job_add_to_dbus_queue(j);
1116         }
1117
1118         /* As last step, kill all remaining job dependencies. */
1119         transaction_clean_dependencies(m);
1120
1121         return 0;
1122
1123 rollback:
1124
1125         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1126                 if (j->installed)
1127                         continue;
1128
1129                 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1130         }
1131
1132         return r;
1133 }
1134
1135 static int transaction_activate(Manager *m, JobMode mode, DBusError *e) {
1136         int r;
1137         unsigned generation = 1;
1138
1139         assert(m);
1140
1141         /* This applies the changes recorded in transaction_jobs to
1142          * the actual list of jobs, if possible. */
1143
1144         /* First step: figure out which jobs matter */
1145         transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1146
1147         /* Second step: Try not to stop any running services if
1148          * we don't have to. Don't try to reverse running
1149          * jobs if we don't have to. */
1150         transaction_minimize_impact(m);
1151
1152         /* Third step: Drop redundant jobs */
1153         transaction_drop_redundant(m);
1154
1155         for (;;) {
1156                 /* Fourth step: Let's remove unneeded jobs that might
1157                  * be lurking. */
1158                 transaction_collect_garbage(m);
1159
1160                 /* Fifth step: verify order makes sense and correct
1161                  * cycles if necessary and possible */
1162                 if ((r = transaction_verify_order(m, &generation, e)) >= 0)
1163                         break;
1164
1165                 if (r != -EAGAIN) {
1166                         log_warning("Requested transaction contains an unfixable cyclic ordering dependency: %s", bus_error(e, r));
1167                         goto rollback;
1168                 }
1169
1170                 /* Let's see if the resulting transaction ordering
1171                  * graph is still cyclic... */
1172         }
1173
1174         for (;;) {
1175                 /* Sixth step: let's drop unmergeable entries if
1176                  * necessary and possible, merge entries we can
1177                  * merge */
1178                 if ((r = transaction_merge_jobs(m, e)) >= 0)
1179                         break;
1180
1181                 if (r != -EAGAIN) {
1182                         log_warning("Requested transaction contains unmergable jobs: %s", bus_error(e, r));
1183                         goto rollback;
1184                 }
1185
1186                 /* Seventh step: an entry got dropped, let's garbage
1187                  * collect its dependencies. */
1188                 transaction_collect_garbage(m);
1189
1190                 /* Let's see if the resulting transaction still has
1191                  * unmergeable entries ... */
1192         }
1193
1194         /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1195         transaction_drop_redundant(m);
1196
1197         /* Ninth step: check whether we can actually apply this */
1198         if (mode == JOB_FAIL)
1199                 if ((r = transaction_is_destructive(m, e)) < 0) {
1200                         log_notice("Requested transaction contradicts existing jobs: %s", bus_error(e, r));
1201                         goto rollback;
1202                 }
1203
1204         /* Tenth step: apply changes */
1205         if ((r = transaction_apply(m)) < 0) {
1206                 log_warning("Failed to apply transaction: %s", strerror(-r));
1207                 goto rollback;
1208         }
1209
1210         assert(hashmap_isempty(m->transaction_jobs));
1211         assert(!m->transaction_anchor);
1212
1213         return 0;
1214
1215 rollback:
1216         transaction_abort(m);
1217         return r;
1218 }
1219
1220 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1221         Job *j, *f;
1222         int r;
1223
1224         assert(m);
1225         assert(unit);
1226
1227         /* Looks for an axisting prospective job and returns that. If
1228          * it doesn't exist it is created and added to the prospective
1229          * jobs list. */
1230
1231         f = hashmap_get(m->transaction_jobs, unit);
1232
1233         LIST_FOREACH(transaction, j, f) {
1234                 assert(j->unit == unit);
1235
1236                 if (j->type == type) {
1237                         if (is_new)
1238                                 *is_new = false;
1239                         return j;
1240                 }
1241         }
1242
1243         if (unit->meta.job && unit->meta.job->type == type)
1244                 j = unit->meta.job;
1245         else if (!(j = job_new(m, type, unit)))
1246                 return NULL;
1247
1248         j->generation = 0;
1249         j->marker = NULL;
1250         j->matters_to_anchor = false;
1251         j->override = override;
1252
1253         LIST_PREPEND(Job, transaction, f, j);
1254
1255         if ((r = hashmap_replace(m->transaction_jobs, unit, f)) < 0) {
1256                 job_free(j);
1257                 return NULL;
1258         }
1259
1260         if (is_new)
1261                 *is_new = true;
1262
1263         log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1264
1265         return j;
1266 }
1267
1268 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1269         assert(m);
1270         assert(j);
1271
1272         if (j->transaction_prev)
1273                 j->transaction_prev->transaction_next = j->transaction_next;
1274         else if (j->transaction_next)
1275                 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1276         else
1277                 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1278
1279         if (j->transaction_next)
1280                 j->transaction_next->transaction_prev = j->transaction_prev;
1281
1282         j->transaction_prev = j->transaction_next = NULL;
1283
1284         while (j->subject_list)
1285                 job_dependency_free(j->subject_list);
1286
1287         while (j->object_list) {
1288                 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1289
1290                 job_dependency_free(j->object_list);
1291
1292                 if (other && delete_dependencies) {
1293                         log_info("Deleting job %s/%s as dependency of job %s/%s",
1294                                   other->unit->meta.id, job_type_to_string(other->type),
1295                                   j->unit->meta.id, job_type_to_string(j->type));
1296                         transaction_delete_job(m, other, delete_dependencies);
1297                 }
1298         }
1299 }
1300
1301 static int transaction_add_job_and_dependencies(
1302                 Manager *m,
1303                 JobType type,
1304                 Unit *unit,
1305                 Job *by,
1306                 bool matters,
1307                 bool override,
1308                 DBusError *e,
1309                 Job **_ret) {
1310         Job *ret;
1311         Iterator i;
1312         Unit *dep;
1313         int r;
1314         bool is_new;
1315
1316         assert(m);
1317         assert(type < _JOB_TYPE_MAX);
1318         assert(unit);
1319
1320         if (unit->meta.load_state != UNIT_LOADED) {
1321                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED, "Unit %s failed to load. See logs for details.", unit->meta.id);
1322                 return -EINVAL;
1323         }
1324
1325         if (!unit_job_is_applicable(unit, type)) {
1326                 dbus_set_error(e, BUS_ERROR_JOB_TYPE_NOT_APPLICABLE, "Job type %s is not applicable for unit %s.", job_type_to_string(type), unit->meta.id);
1327                 return -EBADR;
1328         }
1329
1330         /* First add the job. */
1331         if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1332                 return -ENOMEM;
1333
1334         /* Then, add a link to the job. */
1335         if (!job_dependency_new(by, ret, matters))
1336                 return -ENOMEM;
1337
1338         if (is_new) {
1339                 /* Finally, recursively add in all dependencies. */
1340                 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1341                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1342                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1343                                         goto fail;
1344
1345                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1346                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, e, NULL)) < 0 && r != -EBADR)
1347                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1348
1349                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1350                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, e, NULL)) < 0)
1351                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1352
1353                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1354                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1355                                         goto fail;
1356
1357                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1358                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, e, NULL)) < 0 && r != -EBADR)
1359                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1360
1361                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1362                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1363                                         goto fail;
1364
1365                 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1366
1367                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1368                                 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1369                                         goto fail;
1370                 }
1371
1372                 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1373         }
1374
1375         if (_ret)
1376                 *_ret = ret;
1377
1378         return 0;
1379
1380 fail:
1381         return r;
1382 }
1383
1384 static int transaction_add_isolate_jobs(Manager *m) {
1385         Iterator i;
1386         Unit *u;
1387         char *k;
1388         int r;
1389
1390         assert(m);
1391
1392         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
1393
1394                 /* ignore aliases */
1395                 if (u->meta.id != k)
1396                         continue;
1397
1398                 if (UNIT_VTABLE(u)->no_isolate)
1399                         continue;
1400
1401                 /* No need to stop inactive jobs */
1402                 if (UNIT_IS_INACTIVE_OR_MAINTENANCE(unit_active_state(u)))
1403                         continue;
1404
1405                 /* Is there already something listed for this? */
1406                 if (hashmap_get(m->transaction_jobs, u))
1407                         continue;
1408
1409                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, u, NULL, true, false, NULL, NULL)) < 0)
1410                         log_warning("Cannot add isolate job for unit %s, ignoring: %s", u->meta.id, strerror(-r));
1411         }
1412
1413         return 0;
1414 }
1415
1416 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, DBusError *e, Job **_ret) {
1417         int r;
1418         Job *ret;
1419
1420         assert(m);
1421         assert(type < _JOB_TYPE_MAX);
1422         assert(unit);
1423         assert(mode < _JOB_MODE_MAX);
1424
1425         if (mode == JOB_ISOLATE && type != JOB_START) {
1426                 dbus_set_error(e, BUS_ERROR_INVALID_JOB_MODE, "Isolate is only valid for start.");
1427                 return -EINVAL;
1428         }
1429
1430         log_debug("Trying to enqueue job %s/%s", unit->meta.id, job_type_to_string(type));
1431
1432         if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, e, &ret)) < 0) {
1433                 transaction_abort(m);
1434                 return r;
1435         }
1436
1437         if (mode == JOB_ISOLATE)
1438                 if ((r = transaction_add_isolate_jobs(m)) < 0) {
1439                         transaction_abort(m);
1440                         return r;
1441                 }
1442
1443         if ((r = transaction_activate(m, mode, e)) < 0)
1444                 return r;
1445
1446         log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id);
1447
1448         if (_ret)
1449                 *_ret = ret;
1450
1451         return 0;
1452 }
1453
1454 int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, DBusError *e, Job **_ret) {
1455         Unit *unit;
1456         int r;
1457
1458         assert(m);
1459         assert(type < _JOB_TYPE_MAX);
1460         assert(name);
1461         assert(mode < _JOB_MODE_MAX);
1462
1463         if ((r = manager_load_unit(m, name, NULL, NULL, &unit)) < 0)
1464                 return r;
1465
1466         return manager_add_job(m, type, unit, mode, override, e, _ret);
1467 }
1468
1469 Job *manager_get_job(Manager *m, uint32_t id) {
1470         assert(m);
1471
1472         return hashmap_get(m->jobs, UINT32_TO_PTR(id));
1473 }
1474
1475 Unit *manager_get_unit(Manager *m, const char *name) {
1476         assert(m);
1477         assert(name);
1478
1479         return hashmap_get(m->units, name);
1480 }
1481
1482 unsigned manager_dispatch_load_queue(Manager *m) {
1483         Meta *meta;
1484         unsigned n = 0;
1485
1486         assert(m);
1487
1488         /* Make sure we are not run recursively */
1489         if (m->dispatching_load_queue)
1490                 return 0;
1491
1492         m->dispatching_load_queue = true;
1493
1494         /* Dispatches the load queue. Takes a unit from the queue and
1495          * tries to load its data until the queue is empty */
1496
1497         while ((meta = m->load_queue)) {
1498                 assert(meta->in_load_queue);
1499
1500                 unit_load((Unit*) meta);
1501                 n++;
1502         }
1503
1504         m->dispatching_load_queue = false;
1505         return n;
1506 }
1507
1508 int manager_load_unit_prepare(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1509         Unit *ret;
1510         int r;
1511
1512         assert(m);
1513         assert(name || path);
1514
1515         /* This will prepare the unit for loading, but not actually
1516          * load anything from disk. */
1517
1518         if (path && !is_path(path)) {
1519                 dbus_set_error(e, BUS_ERROR_INVALID_PATH, "Path %s is not absolute.", path);
1520                 return -EINVAL;
1521         }
1522
1523         if (!name)
1524                 name = file_name_from_path(path);
1525
1526         if (!unit_name_is_valid(name)) {
1527                 dbus_set_error(e, BUS_ERROR_INVALID_NAME, "Unit name %s is not valid.", name);
1528                 return -EINVAL;
1529         }
1530
1531         if ((ret = manager_get_unit(m, name))) {
1532                 *_ret = ret;
1533                 return 1;
1534         }
1535
1536         if (!(ret = unit_new(m)))
1537                 return -ENOMEM;
1538
1539         if (path)
1540                 if (!(ret->meta.fragment_path = strdup(path))) {
1541                         unit_free(ret);
1542                         return -ENOMEM;
1543                 }
1544
1545         if ((r = unit_add_name(ret, name)) < 0) {
1546                 unit_free(ret);
1547                 return r;
1548         }
1549
1550         unit_add_to_load_queue(ret);
1551         unit_add_to_dbus_queue(ret);
1552         unit_add_to_gc_queue(ret);
1553
1554         if (_ret)
1555                 *_ret = ret;
1556
1557         return 0;
1558 }
1559
1560 int manager_load_unit(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1561         int r;
1562
1563         assert(m);
1564
1565         /* This will load the service information files, but not actually
1566          * start any services or anything. */
1567
1568         if ((r = manager_load_unit_prepare(m, name, path, e, _ret)) != 0)
1569                 return r;
1570
1571         manager_dispatch_load_queue(m);
1572
1573         if (_ret)
1574                 *_ret = unit_follow_merge(*_ret);
1575
1576         return 0;
1577 }
1578
1579 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1580         Iterator i;
1581         Job *j;
1582
1583         assert(s);
1584         assert(f);
1585
1586         HASHMAP_FOREACH(j, s->jobs, i)
1587                 job_dump(j, f, prefix);
1588 }
1589
1590 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1591         Iterator i;
1592         Unit *u;
1593         const char *t;
1594
1595         assert(s);
1596         assert(f);
1597
1598         HASHMAP_FOREACH_KEY(u, t, s->units, i)
1599                 if (u->meta.id == t)
1600                         unit_dump(u, f, prefix);
1601 }
1602
1603 void manager_clear_jobs(Manager *m) {
1604         Job *j;
1605
1606         assert(m);
1607
1608         transaction_abort(m);
1609
1610         while ((j = hashmap_first(m->jobs)))
1611                 job_free(j);
1612 }
1613
1614 unsigned manager_dispatch_run_queue(Manager *m) {
1615         Job *j;
1616         unsigned n = 0;
1617
1618         if (m->dispatching_run_queue)
1619                 return 0;
1620
1621         m->dispatching_run_queue = true;
1622
1623         while ((j = m->run_queue)) {
1624                 assert(j->installed);
1625                 assert(j->in_run_queue);
1626
1627                 job_run_and_invalidate(j);
1628                 n++;
1629         }
1630
1631         m->dispatching_run_queue = false;
1632         return n;
1633 }
1634
1635 unsigned manager_dispatch_dbus_queue(Manager *m) {
1636         Job *j;
1637         Meta *meta;
1638         unsigned n = 0;
1639
1640         assert(m);
1641
1642         if (m->dispatching_dbus_queue)
1643                 return 0;
1644
1645         m->dispatching_dbus_queue = true;
1646
1647         while ((meta = m->dbus_unit_queue)) {
1648                 assert(meta->in_dbus_queue);
1649
1650                 bus_unit_send_change_signal((Unit*) meta);
1651                 n++;
1652         }
1653
1654         while ((j = m->dbus_job_queue)) {
1655                 assert(j->in_dbus_queue);
1656
1657                 bus_job_send_change_signal(j);
1658                 n++;
1659         }
1660
1661         m->dispatching_dbus_queue = false;
1662         return n;
1663 }
1664
1665 static int manager_process_notify_fd(Manager *m) {
1666         ssize_t n;
1667
1668         assert(m);
1669
1670         for (;;) {
1671                 char buf[4096];
1672                 struct msghdr msghdr;
1673                 struct iovec iovec;
1674                 struct ucred *ucred;
1675                 union {
1676                         struct cmsghdr cmsghdr;
1677                         uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
1678                 } control;
1679                 Unit *u;
1680                 char **tags;
1681
1682                 zero(iovec);
1683                 iovec.iov_base = buf;
1684                 iovec.iov_len = sizeof(buf)-1;
1685
1686                 zero(control);
1687                 zero(msghdr);
1688                 msghdr.msg_iov = &iovec;
1689                 msghdr.msg_iovlen = 1;
1690                 msghdr.msg_control = &control;
1691                 msghdr.msg_controllen = sizeof(control);
1692
1693                 if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) <= 0) {
1694                         if (n >= 0)
1695                                 return -EIO;
1696
1697                         if (errno == EAGAIN)
1698                                 break;
1699
1700                         return -errno;
1701                 }
1702
1703                 if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
1704                     control.cmsghdr.cmsg_level != SOL_SOCKET ||
1705                     control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
1706                     control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
1707                         log_warning("Received notify message without credentials. Ignoring.");
1708                         continue;
1709                 }
1710
1711                 ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
1712
1713                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(ucred->pid))))
1714                         if (!(u = cgroup_unit_by_pid(m, ucred->pid))) {
1715                                 log_warning("Cannot find unit for notify message of PID %lu.", (unsigned long) ucred->pid);
1716                                 continue;
1717                         }
1718
1719                 assert((size_t) n < sizeof(buf));
1720                 buf[n] = 0;
1721                 if (!(tags = strv_split(buf, "\n\r")))
1722                         return -ENOMEM;
1723
1724                 log_debug("Got notification message for unit %s", u->meta.id);
1725
1726                 if (UNIT_VTABLE(u)->notify_message)
1727                         UNIT_VTABLE(u)->notify_message(u, ucred->pid, tags);
1728
1729                 strv_free(tags);
1730         }
1731
1732         return 0;
1733 }
1734
1735 static int manager_dispatch_sigchld(Manager *m) {
1736         assert(m);
1737
1738         for (;;) {
1739                 siginfo_t si;
1740                 Unit *u;
1741                 int r;
1742
1743                 zero(si);
1744
1745                 /* First we call waitd() for a PID and do not reap the
1746                  * zombie. That way we can still access /proc/$PID for
1747                  * it while it is a zombie. */
1748                 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1749
1750                         if (errno == ECHILD)
1751                                 break;
1752
1753                         if (errno == EINTR)
1754                                 continue;
1755
1756                         return -errno;
1757                 }
1758
1759                 if (si.si_pid <= 0)
1760                         break;
1761
1762                 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1763                         char *name = NULL;
1764
1765                         get_process_name(si.si_pid, &name);
1766                         log_debug("Got SIGCHLD for process %lu (%s)", (unsigned long) si.si_pid, strna(name));
1767                         free(name);
1768                 }
1769
1770                 /* Let's flush any message the dying child might still
1771                  * have queued for us. This ensures that the process
1772                  * still exists in /proc so that we can figure out
1773                  * which cgroup and hence unit it belongs to. */
1774                 if ((r = manager_process_notify_fd(m)) < 0)
1775                         return r;
1776
1777                 /* And now figure out the unit this belongs to */
1778                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(si.si_pid))))
1779                         u = cgroup_unit_by_pid(m, si.si_pid);
1780
1781                 /* And now, we actually reap the zombie. */
1782                 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1783                         if (errno == EINTR)
1784                                 continue;
1785
1786                         return -errno;
1787                 }
1788
1789                 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1790                         continue;
1791
1792                 log_debug("Child %lu died (code=%s, status=%i/%s)",
1793                           (long unsigned) si.si_pid,
1794                           sigchld_code_to_string(si.si_code),
1795                           si.si_status,
1796                           strna(si.si_code == CLD_EXITED ? exit_status_to_string(si.si_status) : signal_to_string(si.si_status)));
1797
1798                 if (!u)
1799                         continue;
1800
1801                 log_debug("Child %lu belongs to %s", (long unsigned) si.si_pid, u->meta.id);
1802
1803                 hashmap_remove(m->watch_pids, LONG_TO_PTR(si.si_pid));
1804                 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1805         }
1806
1807         return 0;
1808 }
1809
1810 static int manager_start_target(Manager *m, const char *name, JobMode mode) {
1811         int r;
1812         DBusError error;
1813
1814         dbus_error_init(&error);
1815
1816         log_info("Activating special unit %s", name);
1817
1818         if ((r = manager_add_job_by_name(m, JOB_START, name, mode, true, &error, NULL)) < 0)
1819                 log_error("Failed to enqueue %s job: %s", name, bus_error(&error, r));
1820
1821         dbus_error_free(&error);
1822
1823         return r;
1824 }
1825
1826 static int manager_process_signal_fd(Manager *m) {
1827         ssize_t n;
1828         struct signalfd_siginfo sfsi;
1829         bool sigchld = false;
1830
1831         assert(m);
1832
1833         for (;;) {
1834                 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1835
1836                         if (n >= 0)
1837                                 return -EIO;
1838
1839                         if (errno == EAGAIN)
1840                                 break;
1841
1842                         return -errno;
1843                 }
1844
1845                 log_debug("Received SIG%s", strna(signal_to_string(sfsi.ssi_signo)));
1846
1847                 switch (sfsi.ssi_signo) {
1848
1849                 case SIGCHLD:
1850                         sigchld = true;
1851                         break;
1852
1853                 case SIGTERM:
1854                         if (m->running_as == MANAGER_SYSTEM) {
1855                                 /* This is for compatibility with the
1856                                  * original sysvinit */
1857                                 m->exit_code = MANAGER_REEXECUTE;
1858                                 break;
1859                         }
1860
1861                         /* Fall through */
1862
1863                 case SIGINT:
1864                         if (m->running_as == MANAGER_SYSTEM) {
1865                                 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET, JOB_REPLACE);
1866                                 break;
1867                         }
1868
1869                         /* Run the exit target if there is one, if not, just exit. */
1870                         if (manager_start_target(m, SPECIAL_EXIT_SERVICE, JOB_REPLACE) < 0) {
1871                                 m->exit_code = MANAGER_EXIT;
1872                                 return 0;
1873                         }
1874
1875                         break;
1876
1877                 case SIGWINCH:
1878                         if (m->running_as == MANAGER_SYSTEM)
1879                                 manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE);
1880
1881                         /* This is a nop on non-init */
1882                         break;
1883
1884                 case SIGPWR:
1885                         if (m->running_as == MANAGER_SYSTEM)
1886                                 manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE);
1887
1888                         /* This is a nop on non-init */
1889                         break;
1890
1891                 case SIGUSR1: {
1892                         Unit *u;
1893
1894                         u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
1895
1896                         if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
1897                                 log_info("Trying to reconnect to bus...");
1898                                 bus_init(m);
1899                         }
1900
1901                         if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
1902                                 log_info("Loading D-Bus service...");
1903                                 manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE);
1904                         }
1905
1906                         break;
1907                 }
1908
1909                 case SIGUSR2: {
1910                         FILE *f;
1911                         char *dump = NULL;
1912                         size_t size;
1913
1914                         if (!(f = open_memstream(&dump, &size))) {
1915                                 log_warning("Failed to allocate memory stream.");
1916                                 break;
1917                         }
1918
1919                         manager_dump_units(m, f, "\t");
1920                         manager_dump_jobs(m, f, "\t");
1921
1922                         if (ferror(f)) {
1923                                 fclose(f);
1924                                 free(dump);
1925                                 log_warning("Failed to write status stream");
1926                                 break;
1927                         }
1928
1929                         fclose(f);
1930                         log_dump(LOG_INFO, dump);
1931                         free(dump);
1932
1933                         break;
1934                 }
1935
1936                 case SIGHUP:
1937                         m->exit_code = MANAGER_RELOAD;
1938                         break;
1939
1940                 default: {
1941                         static const char * const table[] = {
1942                                 [0] = SPECIAL_DEFAULT_TARGET,
1943                                 [1] = SPECIAL_RESCUE_TARGET,
1944                                 [2] = SPECIAL_EMERGENCY_SERVICE,
1945                                 [3] = SPECIAL_HALT_TARGET,
1946                                 [4] = SPECIAL_POWEROFF_TARGET,
1947                                 [5] = SPECIAL_REBOOT_TARGET
1948                         };
1949
1950                         if ((int) sfsi.ssi_signo >= SIGRTMIN+0 &&
1951                             (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(table)) {
1952                                 manager_start_target(m, table[sfsi.ssi_signo - SIGRTMIN],
1953                                                      (sfsi.ssi_signo == 1 || sfsi.ssi_signo == 2) ? JOB_ISOLATE : JOB_REPLACE);
1954                                 break;
1955                         }
1956
1957                         log_warning("Got unhandled signal <%s>.", strna(signal_to_string(sfsi.ssi_signo)));
1958                 }
1959                 }
1960         }
1961
1962         if (sigchld)
1963                 return manager_dispatch_sigchld(m);
1964
1965         return 0;
1966 }
1967
1968 static int process_event(Manager *m, struct epoll_event *ev) {
1969         int r;
1970         Watch *w;
1971
1972         assert(m);
1973         assert(ev);
1974
1975         assert(w = ev->data.ptr);
1976
1977         switch (w->type) {
1978
1979         case WATCH_SIGNAL:
1980
1981                 /* An incoming signal? */
1982                 if (ev->events != EPOLLIN)
1983                         return -EINVAL;
1984
1985                 if ((r = manager_process_signal_fd(m)) < 0)
1986                         return r;
1987
1988                 break;
1989
1990         case WATCH_NOTIFY:
1991
1992                 /* An incoming daemon notification event? */
1993                 if (ev->events != EPOLLIN)
1994                         return -EINVAL;
1995
1996                 if ((r = manager_process_notify_fd(m)) < 0)
1997                         return r;
1998
1999                 break;
2000
2001         case WATCH_FD:
2002
2003                 /* Some fd event, to be dispatched to the units */
2004                 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
2005                 break;
2006
2007         case WATCH_TIMER: {
2008                 uint64_t v;
2009                 ssize_t k;
2010
2011                 /* Some timer event, to be dispatched to the units */
2012                 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
2013
2014                         if (k < 0 && (errno == EINTR || errno == EAGAIN))
2015                                 break;
2016
2017                         return k < 0 ? -errno : -EIO;
2018                 }
2019
2020                 UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
2021                 break;
2022         }
2023
2024         case WATCH_MOUNT:
2025                 /* Some mount table change, intended for the mount subsystem */
2026                 mount_fd_event(m, ev->events);
2027                 break;
2028
2029         case WATCH_UDEV:
2030                 /* Some notification from udev, intended for the device subsystem */
2031                 device_fd_event(m, ev->events);
2032                 break;
2033
2034         case WATCH_DBUS_WATCH:
2035                 bus_watch_event(m, w, ev->events);
2036                 break;
2037
2038         case WATCH_DBUS_TIMEOUT:
2039                 bus_timeout_event(m, w, ev->events);
2040                 break;
2041
2042         default:
2043                 assert_not_reached("Unknown epoll event type.");
2044         }
2045
2046         return 0;
2047 }
2048
2049 int manager_loop(Manager *m) {
2050         int r;
2051
2052         RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
2053
2054         assert(m);
2055         m->exit_code = MANAGER_RUNNING;
2056
2057         /* Release the path cache */
2058         set_free_free(m->unit_path_cache);
2059         m->unit_path_cache = NULL;
2060
2061         /* There might still be some zombies hanging around from
2062          * before we were exec()'ed. Leat's reap them */
2063         if ((r = manager_dispatch_sigchld(m)) < 0)
2064                 return r;
2065
2066         while (m->exit_code == MANAGER_RUNNING) {
2067                 struct epoll_event event;
2068                 int n;
2069
2070                 if (!ratelimit_test(&rl)) {
2071                         /* Yay, something is going seriously wrong, pause a little */
2072                         log_warning("Looping too fast. Throttling execution a little.");
2073                         sleep(1);
2074                 }
2075
2076                 if (manager_dispatch_load_queue(m) > 0)
2077                         continue;
2078
2079                 if (manager_dispatch_run_queue(m) > 0)
2080                         continue;
2081
2082                 if (bus_dispatch(m) > 0)
2083                         continue;
2084
2085                 if (manager_dispatch_cleanup_queue(m) > 0)
2086                         continue;
2087
2088                 if (manager_dispatch_gc_queue(m) > 0)
2089                         continue;
2090
2091                 if (manager_dispatch_dbus_queue(m) > 0)
2092                         continue;
2093
2094                 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
2095
2096                         if (errno == EINTR)
2097                                 continue;
2098
2099                         return -errno;
2100                 }
2101
2102                 assert(n == 1);
2103
2104                 if ((r = process_event(m, &event)) < 0)
2105                         return r;
2106         }
2107
2108         return m->exit_code;
2109 }
2110
2111 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
2112         char *n;
2113         Unit *u;
2114
2115         assert(m);
2116         assert(s);
2117         assert(_u);
2118
2119         if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
2120                 return -EINVAL;
2121
2122         if (!(n = bus_path_unescape(s+31)))
2123                 return -ENOMEM;
2124
2125         u = manager_get_unit(m, n);
2126         free(n);
2127
2128         if (!u)
2129                 return -ENOENT;
2130
2131         *_u = u;
2132
2133         return 0;
2134 }
2135
2136 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
2137         Job *j;
2138         unsigned id;
2139         int r;
2140
2141         assert(m);
2142         assert(s);
2143         assert(_j);
2144
2145         if (!startswith(s, "/org/freedesktop/systemd1/job/"))
2146                 return -EINVAL;
2147
2148         if ((r = safe_atou(s + 30, &id)) < 0)
2149                 return r;
2150
2151         if (!(j = manager_get_job(m, id)))
2152                 return -ENOENT;
2153
2154         *_j = j;
2155
2156         return 0;
2157 }
2158
2159 static bool manager_utmp_good(Manager *m) {
2160         int r;
2161
2162         assert(m);
2163
2164         if ((r = mount_path_is_mounted(m, _PATH_UTMPX)) <= 0) {
2165
2166                 if (r < 0)
2167                         log_warning("Failed to determine whether " _PATH_UTMPX " is mounted: %s", strerror(-r));
2168
2169                 return false;
2170         }
2171
2172         return true;
2173 }
2174
2175 void manager_write_utmp_reboot(Manager *m) {
2176         int r;
2177
2178         assert(m);
2179
2180         if (m->utmp_reboot_written)
2181                 return;
2182
2183         if (m->running_as != MANAGER_SYSTEM)
2184                 return;
2185
2186         if (!manager_utmp_good(m))
2187                 return;
2188
2189         if ((r = utmp_put_reboot(m->startup_timestamp.realtime)) < 0) {
2190
2191                 if (r != -ENOENT && r != -EROFS)
2192                         log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
2193
2194                 return;
2195         }
2196
2197         m->utmp_reboot_written = true;
2198 }
2199
2200 void manager_write_utmp_runlevel(Manager *m, Unit *u) {
2201         int runlevel, r;
2202
2203         assert(m);
2204         assert(u);
2205
2206         if (u->meta.type != UNIT_TARGET)
2207                 return;
2208
2209         if (m->running_as != MANAGER_SYSTEM)
2210                 return;
2211
2212         if (!manager_utmp_good(m))
2213                 return;
2214
2215         if ((runlevel = target_get_runlevel(TARGET(u))) <= 0)
2216                 return;
2217
2218         if ((r = utmp_put_runlevel(0, runlevel, 0)) < 0) {
2219
2220                 if (r != -ENOENT && r != -EROFS)
2221                         log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
2222         }
2223 }
2224
2225 void manager_dispatch_bus_name_owner_changed(
2226                 Manager *m,
2227                 const char *name,
2228                 const char* old_owner,
2229                 const char *new_owner) {
2230
2231         Unit *u;
2232
2233         assert(m);
2234         assert(name);
2235
2236         if (!(u = hashmap_get(m->watch_bus, name)))
2237                 return;
2238
2239         UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
2240 }
2241
2242 void manager_dispatch_bus_query_pid_done(
2243                 Manager *m,
2244                 const char *name,
2245                 pid_t pid) {
2246
2247         Unit *u;
2248
2249         assert(m);
2250         assert(name);
2251         assert(pid >= 1);
2252
2253         if (!(u = hashmap_get(m->watch_bus, name)))
2254                 return;
2255
2256         UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
2257 }
2258
2259 int manager_open_serialization(FILE **_f) {
2260         char *path;
2261         mode_t saved_umask;
2262         int fd;
2263         FILE *f;
2264
2265         assert(_f);
2266
2267         if (asprintf(&path, "/dev/shm/systemd-%u.dump-XXXXXX", (unsigned) getpid()) < 0)
2268                 return -ENOMEM;
2269
2270         saved_umask = umask(0077);
2271         fd = mkostemp(path, O_RDWR|O_CLOEXEC);
2272         umask(saved_umask);
2273
2274         if (fd < 0) {
2275                 free(path);
2276                 return -errno;
2277         }
2278
2279         unlink(path);
2280
2281         log_debug("Serializing state to %s", path);
2282         free(path);
2283
2284         if (!(f = fdopen(fd, "w+")) < 0)
2285                 return -errno;
2286
2287         *_f = f;
2288
2289         return 0;
2290 }
2291
2292 int manager_serialize(Manager *m, FILE *f, FDSet *fds) {
2293         Iterator i;
2294         Unit *u;
2295         const char *t;
2296         int r;
2297
2298         assert(m);
2299         assert(f);
2300         assert(fds);
2301
2302         HASHMAP_FOREACH_KEY(u, t, m->units, i) {
2303                 if (u->meta.id != t)
2304                         continue;
2305
2306                 if (!unit_can_serialize(u))
2307                         continue;
2308
2309                 /* Start marker */
2310                 fputs(u->meta.id, f);
2311                 fputc('\n', f);
2312
2313                 if ((r = unit_serialize(u, f, fds)) < 0)
2314                         return r;
2315         }
2316
2317         if (ferror(f))
2318                 return -EIO;
2319
2320         return 0;
2321 }
2322
2323 int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
2324         int r = 0;
2325
2326         assert(m);
2327         assert(f);
2328
2329         log_debug("Deserializing state...");
2330
2331         m->deserializing = true;
2332
2333         for (;;) {
2334                 Unit *u;
2335                 char name[UNIT_NAME_MAX+2];
2336
2337                 /* Start marker */
2338                 if (!fgets(name, sizeof(name), f)) {
2339                         if (feof(f))
2340                                 break;
2341
2342                         r = -errno;
2343                         goto finish;
2344                 }
2345
2346                 char_array_0(name);
2347
2348                 if ((r = manager_load_unit(m, strstrip(name), NULL, NULL, &u)) < 0)
2349                         goto finish;
2350
2351                 if ((r = unit_deserialize(u, f, fds)) < 0)
2352                         goto finish;
2353         }
2354
2355         if (ferror(f)) {
2356                 r = -EIO;
2357                 goto finish;
2358         }
2359
2360         r = 0;
2361
2362 finish:
2363         m->deserializing = false;
2364
2365         return r;
2366 }
2367
2368 int manager_reload(Manager *m) {
2369         int r, q;
2370         FILE *f;
2371         FDSet *fds;
2372
2373         assert(m);
2374
2375         if ((r = manager_open_serialization(&f)) < 0)
2376                 return r;
2377
2378         if (!(fds = fdset_new())) {
2379                 r = -ENOMEM;
2380                 goto finish;
2381         }
2382
2383         if ((r = manager_serialize(m, f, fds)) < 0)
2384                 goto finish;
2385
2386         if (fseeko(f, 0, SEEK_SET) < 0) {
2387                 r = -errno;
2388                 goto finish;
2389         }
2390
2391         /* From here on there is no way back. */
2392         manager_clear_jobs_and_units(m);
2393
2394         /* Find new unit paths */
2395         lookup_paths_free(&m->lookup_paths);
2396         if ((q = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
2397                 r = q;
2398
2399         /* First, enumerate what we can from all config files */
2400         if ((q = manager_enumerate(m)) < 0)
2401                 r = q;
2402
2403         /* Second, deserialize our stored data */
2404         if ((q = manager_deserialize(m, f, fds)) < 0)
2405                 r = q;
2406
2407         fclose(f);
2408         f = NULL;
2409
2410         /* Third, fire things up! */
2411         if ((q = manager_coldplug(m)) < 0)
2412                 r = q;
2413
2414 finish:
2415         if (f)
2416                 fclose(f);
2417
2418         if (fds)
2419                 fdset_free(fds);
2420
2421         return r;
2422 }
2423
2424 bool manager_is_booting_or_shutting_down(Manager *m) {
2425         Unit *u;
2426
2427         assert(m);
2428
2429         /* Is the initial job still around? */
2430         if (manager_get_job(m, 1))
2431                 return true;
2432
2433         /* Is there a job for the shutdown target? */
2434         if (((u = manager_get_unit(m, SPECIAL_SHUTDOWN_TARGET))))
2435                 return !!u->meta.job;
2436
2437         return false;
2438 }
2439
2440 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
2441         [MANAGER_SYSTEM] = "system",
2442         [MANAGER_SESSION] = "session"
2443 };
2444
2445 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);