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