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_family_t) + 1 + strlen(sa.un.sun_path+1)) < 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         /* If we will deserialize make sure that during enumeration
 548          * this is already known, so we increase the counter here
 549          * already */
 550         if (serialization)
 551                 m->n_deserializing ++;
 552
 553         /* First, enumerate what we can from all config files */
 554         r = manager_enumerate(m);
 555
 556         /* Second, deserialize if there is something to deserialize */
 557         if (serialization)
 558                 if ((q = manager_deserialize(m, serialization, fds)) < 0)
 559                         r = q;
 560
 561         /* Third, fire things up! */
 562         if ((q = manager_coldplug(m)) < 0)
 563                 r = q;
 564
 565         if (serialization) {
 566                 assert(m->n_deserializing > 0);
 567                 m->n_deserializing --;
 568         }
 569
 570         /* Now that the initial devices are available, let's see if we
 571          * can write the utmp file */
 572         manager_write_utmp_reboot(m);
 573
 574         return r;
 575 }
 576
 577 static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) {
 578         assert(m);
 579         assert(j);
 580
 581         /* Deletes one job from the transaction */
 582
 583         manager_transaction_unlink_job(m, j, delete_dependencies);
 584
 585         if (!j->installed)
 586                 job_free(j);
 587 }
 588
 589 static void transaction_delete_unit(Manager *m, Unit *u) {
 590         Job *j;
 591
 592         /* Deletes all jobs associated with a certain unit from the
 593          * transaction */
 594
 595         while ((j = hashmap_get(m->transaction_jobs, u)))
 596                 transaction_delete_job(m, j, true);
 597 }
 598
 599 static void transaction_clean_dependencies(Manager *m) {
 600         Iterator i;
 601         Job *j;
 602
 603         assert(m);
 604
 605         /* Drops all dependencies of all installed jobs */
 606
 607         HASHMAP_FOREACH(j, m->jobs, i) {
 608                 while (j->subject_list)
 609                         job_dependency_free(j->subject_list);
 610                 while (j->object_list)
 611                         job_dependency_free(j->object_list);
 612         }
 613
 614         assert(!m->transaction_anchor);
 615 }
 616
 617 static void transaction_abort(Manager *m) {
 618         Job *j;
 619
 620         assert(m);
 621
 622         while ((j = hashmap_first(m->transaction_jobs)))
 623                 if (j->installed)
 624                         transaction_delete_job(m, j, true);
 625                 else
 626                         job_free(j);
 627
 628         assert(hashmap_isempty(m->transaction_jobs));
 629
 630         transaction_clean_dependencies(m);
 631 }
 632
 633 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
 634         JobDependency *l;
 635
 636         assert(m);
 637
 638         /* A recursive sweep through the graph that marks all units
 639          * that matter to the anchor job, i.e. are directly or
 640          * indirectly a dependency of the anchor job via paths that
 641          * are fully marked as mattering. */
 642
 643         if (j)
 644                 l = j->subject_list;
 645         else
 646                 l = m->transaction_anchor;
 647
 648         LIST_FOREACH(subject, l, l) {
 649
 650                 /* This link does not matter */
 651                 if (!l->matters)
 652                         continue;
 653
 654                 /* This unit has already been marked */
 655                 if (l->object->generation == generation)
 656                         continue;
 657
 658                 l->object->matters_to_anchor = true;
 659                 l->object->generation = generation;
 660
 661                 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
 662         }
 663 }
 664
 665 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
 666         JobDependency *l, *last;
 667
 668         assert(j);
 669         assert(other);
 670         assert(j->unit == other->unit);
 671         assert(!j->installed);
 672
 673         /* Merges 'other' into 'j' and then deletes j. */
 674
 675         j->type = t;
 676         j->state = JOB_WAITING;
 677         j->override = j->override || other->override;
 678
 679         j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
 680
 681         /* Patch us in as new owner of the JobDependency objects */
 682         last = NULL;
 683         LIST_FOREACH(subject, l, other->subject_list) {
 684                 assert(l->subject == other);
 685                 l->subject = j;
 686                 last = l;
 687         }
 688
 689         /* Merge both lists */
 690         if (last) {
 691                 last->subject_next = j->subject_list;
 692                 if (j->subject_list)
 693                         j->subject_list->subject_prev = last;
 694                 j->subject_list = other->subject_list;
 695         }
 696
 697         /* Patch us in as new owner of the JobDependency objects */
 698         last = NULL;
 699         LIST_FOREACH(object, l, other->object_list) {
 700                 assert(l->object == other);
 701                 l->object = j;
 702                 last = l;
 703         }
 704
 705         /* Merge both lists */
 706         if (last) {
 707                 last->object_next = j->object_list;
 708                 if (j->object_list)
 709                         j->object_list->object_prev = last;
 710                 j->object_list = other->object_list;
 711         }
 712
 713         /* Kill the other job */
 714         other->subject_list = NULL;
 715         other->object_list = NULL;
 716         transaction_delete_job(m, other, true);
 717 }
 718
 719 static int delete_one_unmergeable_job(Manager *m, Job *j) {
 720         Job *k;
 721
 722         assert(j);
 723
 724         /* Tries to delete one item in the linked list
 725          * j->transaction_next->transaction_next->... that conflicts
 726          * whith another one, in an attempt to make an inconsistent
 727          * transaction work. */
 728
 729         /* We rely here on the fact that if a merged with b does not
 730          * merge with c, either a or b merge with c neither */
 731         LIST_FOREACH(transaction, j, j)
 732                 LIST_FOREACH(transaction, k, j->transaction_next) {
 733                         Job *d;
 734
 735                         /* Is this one mergeable? Then skip it */
 736                         if (job_type_is_mergeable(j->type, k->type))
 737                                 continue;
 738
 739                         /* Ok, we found two that conflict, let's see if we can
 740                          * drop one of them */
 741                         if (!j->matters_to_anchor)
 742                                 d = j;
 743                         else if (!k->matters_to_anchor)
 744                                 d = k;
 745                         else
 746                                 return -ENOEXEC;
 747
 748                         /* Ok, we can drop one, so let's do so. */
 749                         log_notice("Trying to fix job merging by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type));
 750                         transaction_delete_job(m, d, true);
 751                         return 0;
 752                 }
 753
 754         return -EINVAL;
 755 }
 756
 757 static int transaction_merge_jobs(Manager *m, DBusError *e) {
 758         Job *j;
 759         Iterator i;
 760         int r;
 761
 762         assert(m);
 763
 764         /* First step, check whether any of the jobs for one specific
 765          * task conflict. If so, try to drop one of them. */
 766         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 767                 JobType t;
 768                 Job *k;
 769
 770                 t = j->type;
 771                 LIST_FOREACH(transaction, k, j->transaction_next) {
 772                         if ((r = job_type_merge(&t, k->type)) >= 0)
 773                                 continue;
 774
 775                         /* OK, we could not merge all jobs for this
 776                          * action. Let's see if we can get rid of one
 777                          * of them */
 778
 779                         if ((r = delete_one_unmergeable_job(m, j)) >= 0)
 780                                 /* Ok, we managed to drop one, now
 781                                  * let's ask our callers to call us
 782                                  * again after garbage collecting */
 783                                 return -EAGAIN;
 784
 785                         /* We couldn't merge anything. Failure */
 786                         dbus_set_error(e, BUS_ERROR_TRANSACTION_JOBS_CONFLICTING, "Transaction contains conflicting jobs '%s' and '%s' for %s. Probably contradicting requirement dependencies configured.",
 787                                        job_type_to_string(t), job_type_to_string(k->type), k->unit->meta.id);
 788                         return r;
 789                 }
 790         }
 791
 792         /* Second step, merge the jobs. */
 793         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 794                 JobType t = j->type;
 795                 Job *k;
 796
 797                 /* Merge all transactions */
 798                 LIST_FOREACH(transaction, k, j->transaction_next)
 799                         assert_se(job_type_merge(&t, k->type) == 0);
 800
 801                 /* If an active job is mergeable, merge it too */
 802                 if (j->unit->meta.job)
 803                         job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
 804
 805                 while ((k = j->transaction_next)) {
 806                         if (j->installed) {
 807                                 transaction_merge_and_delete_job(m, k, j, t);
 808                                 j = k;
 809                         } else
 810                                 transaction_merge_and_delete_job(m, j, k, t);
 811                 }
 812
 813                 assert(!j->transaction_next);
 814                 assert(!j->transaction_prev);
 815         }
 816
 817         return 0;
 818 }
 819
 820 static void transaction_drop_redundant(Manager *m) {
 821         bool again;
 822
 823         assert(m);
 824
 825         /* Goes through the transaction and removes all jobs that are
 826          * a noop */
 827
 828         do {
 829                 Job *j;
 830                 Iterator i;
 831
 832                 again = false;
 833
 834                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 835                         bool changes_something = false;
 836                         Job *k;
 837
 838                         LIST_FOREACH(transaction, k, j) {
 839
 840                                 if (!job_is_anchor(k) &&
 841                                     job_type_is_redundant(k->type, unit_active_state(k->unit)))
 842                                         continue;
 843
 844                                 changes_something = true;
 845                                 break;
 846                         }
 847
 848                         if (changes_something)
 849                                 continue;
 850
 851                         log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type));
 852                         transaction_delete_job(m, j, false);
 853                         again = true;
 854                         break;
 855                 }
 856
 857         } while (again);
 858 }
 859
 860 static bool unit_matters_to_anchor(Unit *u, Job *j) {
 861         assert(u);
 862         assert(!j->transaction_prev);
 863
 864         /* Checks whether at least one of the jobs for this unit
 865          * matters to the anchor. */
 866
 867         LIST_FOREACH(transaction, j, j)
 868                 if (j->matters_to_anchor)
 869                         return true;
 870
 871         return false;
 872 }
 873
 874 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation, DBusError *e) {
 875         Iterator i;
 876         Unit *u;
 877         int r;
 878
 879         assert(m);
 880         assert(j);
 881         assert(!j->transaction_prev);
 882
 883         /* Does a recursive sweep through the ordering graph, looking
 884          * for a cycle. If we find cycle we try to break it. */
 885
 886         /* Have we seen this before? */
 887         if (j->generation == generation) {
 888                 Job *k;
 889
 890                 /* If the marker is NULL we have been here already and
 891                  * decided the job was loop-free from here. Hence
 892                  * shortcut things and return right-away. */
 893                 if (!j->marker)
 894                         return 0;
 895
 896                 /* So, the marker is not NULL and we already have been
 897                  * here. We have a cycle. Let's try to break it. We go
 898                  * backwards in our path and try to find a suitable
 899                  * job to remove. We use the marker to find our way
 900                  * back, since smart how we are we stored our way back
 901                  * in there. */
 902                 log_warning("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type));
 903
 904                 for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) {
 905
 906                         log_info("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 907
 908                         if (!k->installed &&
 909                             !unit_matters_to_anchor(k->unit, k)) {
 910                                 /* Ok, we can drop this one, so let's
 911                                  * do so. */
 912                                 log_warning("Breaking order cycle by deleting job %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 913                                 transaction_delete_unit(m, k->unit);
 914                                 return -EAGAIN;
 915                         }
 916
 917                         /* Check if this in fact was the beginning of
 918                          * the cycle */
 919                         if (k == j)
 920                                 break;
 921                 }
 922
 923                 log_error("Unable to break cycle");
 924
 925                 dbus_set_error(e, BUS_ERROR_TRANSACTION_ORDER_IS_CYCLIC, "Transaction order is cyclic. See logs for details.");
 926                 return -ENOEXEC;
 927         }
 928
 929         /* Make the marker point to where we come from, so that we can
 930          * find our way backwards if we want to break a cycle. We use
 931          * a special marker for the beginning: we point to
 932          * ourselves. */
 933         j->marker = from ? from : j;
 934         j->generation = generation;
 935
 936         /* We assume that the the dependencies are bidirectional, and
 937          * hence can ignore UNIT_AFTER */
 938         SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
 939                 Job *o;
 940
 941                 /* Is there a job for this unit? */
 942                 if (!(o = hashmap_get(m->transaction_jobs, u)))
 943
 944                         /* Ok, there is no job for this in the
 945                          * transaction, but maybe there is already one
 946                          * running? */
 947                         if (!(o = u->meta.job))
 948                                 continue;
 949
 950                 if ((r = transaction_verify_order_one(m, o, j, generation, e)) < 0)
 951                         return r;
 952         }
 953
 954         /* Ok, let's backtrack, and remember that this entry is not on
 955          * our path anymore. */
 956         j->marker = NULL;
 957
 958         return 0;
 959 }
 960
 961 static int transaction_verify_order(Manager *m, unsigned *generation, DBusError *e) {
 962         Job *j;
 963         int r;
 964         Iterator i;
 965         unsigned g;
 966
 967         assert(m);
 968         assert(generation);
 969
 970         /* Check if the ordering graph is cyclic. If it is, try to fix
 971          * that up by dropping one of the jobs. */
 972
 973         g = (*generation)++;
 974
 975         HASHMAP_FOREACH(j, m->transaction_jobs, i)
 976                 if ((r = transaction_verify_order_one(m, j, NULL, g, e)) < 0)
 977                         return r;
 978
 979         return 0;
 980 }
 981
 982 static void transaction_collect_garbage(Manager *m) {
 983         bool again;
 984
 985         assert(m);
 986
 987         /* Drop jobs that are not required by any other job */
 988
 989         do {
 990                 Iterator i;
 991                 Job *j;
 992
 993                 again = false;
 994
 995                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 996                         if (j->object_list)
 997                                 continue;
 998
 999                         log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type));
1000                         transaction_delete_job(m, j, true);
1001                         again = true;
1002                         break;
1003                 }
1004
1005         } while (again);
1006 }
1007
1008 static int transaction_is_destructive(Manager *m, DBusError *e) {
1009         Iterator i;
1010         Job *j;
1011
1012         assert(m);
1013
1014         /* Checks whether applying this transaction means that
1015          * existing jobs would be replaced */
1016
1017         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1018
1019                 /* Assume merged */
1020                 assert(!j->transaction_prev);
1021                 assert(!j->transaction_next);
1022
1023                 if (j->unit->meta.job &&
1024                     j->unit->meta.job != j &&
1025                     !job_type_is_superset(j->type, j->unit->meta.job->type)) {
1026
1027                         dbus_set_error(e, BUS_ERROR_TRANSACTION_IS_DESTRUCTIVE, "Transaction is destructive.");
1028                         return -EEXIST;
1029                 }
1030         }
1031
1032         return 0;
1033 }
1034
1035 static void transaction_minimize_impact(Manager *m) {
1036         bool again;
1037         assert(m);
1038
1039         /* Drops all unnecessary jobs that reverse already active jobs
1040          * or that stop a running service. */
1041
1042         do {
1043                 Job *j;
1044                 Iterator i;
1045
1046                 again = false;
1047
1048                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1049                         LIST_FOREACH(transaction, j, j) {
1050                                 bool stops_running_service, changes_existing_job;
1051
1052                                 /* If it matters, we shouldn't drop it */
1053                                 if (j->matters_to_anchor)
1054                                         continue;
1055
1056                                 /* Would this stop a running service?
1057                                  * Would this change an existing job?
1058                                  * If so, let's drop this entry */
1059
1060                                 stops_running_service =
1061                                         j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
1062
1063                                 changes_existing_job =
1064                                         j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->state);
1065
1066                                 if (!stops_running_service && !changes_existing_job)
1067                                         continue;
1068
1069                                 if (stops_running_service)
1070                                         log_info("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type));
1071
1072                                 if (changes_existing_job)
1073                                         log_info("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type));
1074
1075                                 /* Ok, let's get rid of this */
1076                                 log_info("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type));
1077
1078                                 transaction_delete_job(m, j, true);
1079                                 again = true;
1080                                 break;
1081                         }
1082
1083                         if (again)
1084                                 break;
1085                 }
1086
1087         } while (again);
1088 }
1089
1090 static int transaction_apply(Manager *m) {
1091         Iterator i;
1092         Job *j;
1093         int r;
1094
1095         /* Moves the transaction jobs to the set of active jobs */
1096
1097         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1098                 /* Assume merged */
1099                 assert(!j->transaction_prev);
1100                 assert(!j->transaction_next);
1101
1102                 if (j->installed)
1103                         continue;
1104
1105                 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
1106                         goto rollback;
1107         }
1108
1109         while ((j = hashmap_steal_first(m->transaction_jobs))) {
1110                 if (j->installed)
1111                         continue;
1112
1113                 if (j->unit->meta.job)
1114                         job_free(j->unit->meta.job);
1115
1116                 j->unit->meta.job = j;
1117                 j->installed = true;
1118
1119                 /* We're fully installed. Now let's free data we don't
1120                  * need anymore. */
1121
1122                 assert(!j->transaction_next);
1123                 assert(!j->transaction_prev);
1124
1125                 job_add_to_run_queue(j);
1126                 job_add_to_dbus_queue(j);
1127         }
1128
1129         /* As last step, kill all remaining job dependencies. */
1130         transaction_clean_dependencies(m);
1131
1132         return 0;
1133
1134 rollback:
1135
1136         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1137                 if (j->installed)
1138                         continue;
1139
1140                 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1141         }
1142
1143         return r;
1144 }
1145
1146 static int transaction_activate(Manager *m, JobMode mode, DBusError *e) {
1147         int r;
1148         unsigned generation = 1;
1149
1150         assert(m);
1151
1152         /* This applies the changes recorded in transaction_jobs to
1153          * the actual list of jobs, if possible. */
1154
1155         /* First step: figure out which jobs matter */
1156         transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1157
1158         /* Second step: Try not to stop any running services if
1159          * we don't have to. Don't try to reverse running
1160          * jobs if we don't have to. */
1161         transaction_minimize_impact(m);
1162
1163         /* Third step: Drop redundant jobs */
1164         transaction_drop_redundant(m);
1165
1166         for (;;) {
1167                 /* Fourth step: Let's remove unneeded jobs that might
1168                  * be lurking. */
1169                 transaction_collect_garbage(m);
1170
1171                 /* Fifth step: verify order makes sense and correct
1172                  * cycles if necessary and possible */
1173                 if ((r = transaction_verify_order(m, &generation, e)) >= 0)
1174                         break;
1175
1176                 if (r != -EAGAIN) {
1177                         log_warning("Requested transaction contains an unfixable cyclic ordering dependency: %s", bus_error(e, r));
1178                         goto rollback;
1179                 }
1180
1181                 /* Let's see if the resulting transaction ordering
1182                  * graph is still cyclic... */
1183         }
1184
1185         for (;;) {
1186                 /* Sixth step: let's drop unmergeable entries if
1187                  * necessary and possible, merge entries we can
1188                  * merge */
1189                 if ((r = transaction_merge_jobs(m, e)) >= 0)
1190                         break;
1191
1192                 if (r != -EAGAIN) {
1193                         log_warning("Requested transaction contains unmergable jobs: %s", bus_error(e, r));
1194                         goto rollback;
1195                 }
1196
1197                 /* Seventh step: an entry got dropped, let's garbage
1198                  * collect its dependencies. */
1199                 transaction_collect_garbage(m);
1200
1201                 /* Let's see if the resulting transaction still has
1202                  * unmergeable entries ... */
1203         }
1204
1205         /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1206         transaction_drop_redundant(m);
1207
1208         /* Ninth step: check whether we can actually apply this */
1209         if (mode == JOB_FAIL)
1210                 if ((r = transaction_is_destructive(m, e)) < 0) {
1211                         log_notice("Requested transaction contradicts existing jobs: %s", bus_error(e, r));
1212                         goto rollback;
1213                 }
1214
1215         /* Tenth step: apply changes */
1216         if ((r = transaction_apply(m)) < 0) {
1217                 log_warning("Failed to apply transaction: %s", strerror(-r));
1218                 goto rollback;
1219         }
1220
1221         assert(hashmap_isempty(m->transaction_jobs));
1222         assert(!m->transaction_anchor);
1223
1224         return 0;
1225
1226 rollback:
1227         transaction_abort(m);
1228         return r;
1229 }
1230
1231 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1232         Job *j, *f;
1233         int r;
1234
1235         assert(m);
1236         assert(unit);
1237
1238         /* Looks for an axisting prospective job and returns that. If
1239          * it doesn't exist it is created and added to the prospective
1240          * jobs list. */
1241
1242         f = hashmap_get(m->transaction_jobs, unit);
1243
1244         LIST_FOREACH(transaction, j, f) {
1245                 assert(j->unit == unit);
1246
1247                 if (j->type == type) {
1248                         if (is_new)
1249                                 *is_new = false;
1250                         return j;
1251                 }
1252         }
1253
1254         if (unit->meta.job && unit->meta.job->type == type)
1255                 j = unit->meta.job;
1256         else if (!(j = job_new(m, type, unit)))
1257                 return NULL;
1258
1259         j->generation = 0;
1260         j->marker = NULL;
1261         j->matters_to_anchor = false;
1262         j->override = override;
1263
1264         LIST_PREPEND(Job, transaction, f, j);
1265
1266         if ((r = hashmap_replace(m->transaction_jobs, unit, f)) < 0) {
1267                 job_free(j);
1268                 return NULL;
1269         }
1270
1271         if (is_new)
1272                 *is_new = true;
1273
1274         log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1275
1276         return j;
1277 }
1278
1279 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1280         assert(m);
1281         assert(j);
1282
1283         if (j->transaction_prev)
1284                 j->transaction_prev->transaction_next = j->transaction_next;
1285         else if (j->transaction_next)
1286                 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1287         else
1288                 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1289
1290         if (j->transaction_next)
1291                 j->transaction_next->transaction_prev = j->transaction_prev;
1292
1293         j->transaction_prev = j->transaction_next = NULL;
1294
1295         while (j->subject_list)
1296                 job_dependency_free(j->subject_list);
1297
1298         while (j->object_list) {
1299                 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1300
1301                 job_dependency_free(j->object_list);
1302
1303                 if (other && delete_dependencies) {
1304                         log_info("Deleting job %s/%s as dependency of job %s/%s",
1305                                   other->unit->meta.id, job_type_to_string(other->type),
1306                                   j->unit->meta.id, job_type_to_string(j->type));
1307                         transaction_delete_job(m, other, delete_dependencies);
1308                 }
1309         }
1310 }
1311
1312 static int transaction_add_job_and_dependencies(
1313                 Manager *m,
1314                 JobType type,
1315                 Unit *unit,
1316                 Job *by,
1317                 bool matters,
1318                 bool override,
1319                 DBusError *e,
1320                 Job **_ret) {
1321         Job *ret;
1322         Iterator i;
1323         Unit *dep;
1324         int r;
1325         bool is_new;
1326
1327         assert(m);
1328         assert(type < _JOB_TYPE_MAX);
1329         assert(unit);
1330
1331         if (unit->meta.load_state != UNIT_LOADED) {
1332                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED, "Unit %s failed to load. See logs for details.", unit->meta.id);
1333                 return -EINVAL;
1334         }
1335
1336         if (!unit_job_is_applicable(unit, type)) {
1337                 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);
1338                 return -EBADR;
1339         }
1340
1341         /* First add the job. */
1342         if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1343                 return -ENOMEM;
1344
1345         /* Then, add a link to the job. */
1346         if (!job_dependency_new(by, ret, matters))
1347                 return -ENOMEM;
1348
1349         if (is_new) {
1350                 /* Finally, recursively add in all dependencies. */
1351                 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1352                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1353                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1354                                         goto fail;
1355
1356                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1357                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, e, NULL)) < 0 && r != -EBADR) {
1358                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1359                                         dbus_error_free(e);
1360                                 }
1361
1362                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1363                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, e, NULL)) < 0) {
1364                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1365                                         dbus_error_free(e);
1366                                 }
1367
1368                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1369                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1370                                         goto fail;
1371
1372                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1373                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, e, NULL)) < 0 && r != -EBADR) {
1374                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1375                                         dbus_error_free(e);
1376                                 }
1377
1378                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1379                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1380                                         goto fail;
1381
1382                 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1383
1384                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1385                                 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, e, NULL)) < 0 && r != -EBADR)
1386                                         goto fail;
1387                 }
1388
1389                 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1390         }
1391
1392         if (_ret)
1393                 *_ret = ret;
1394
1395         return 0;
1396
1397 fail:
1398         return r;
1399 }
1400
1401 static int transaction_add_isolate_jobs(Manager *m) {
1402         Iterator i;
1403         Unit *u;
1404         char *k;
1405         int r;
1406
1407         assert(m);
1408
1409         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
1410
1411                 /* ignore aliases */
1412                 if (u->meta.id != k)
1413                         continue;
1414
1415                 if (UNIT_VTABLE(u)->no_isolate)
1416                         continue;
1417
1418                 /* No need to stop inactive jobs */
1419                 if (UNIT_IS_INACTIVE_OR_MAINTENANCE(unit_active_state(u)))
1420                         continue;
1421
1422                 /* Is there already something listed for this? */
1423                 if (hashmap_get(m->transaction_jobs, u))
1424                         continue;
1425
1426                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, u, NULL, true, false, NULL, NULL)) < 0)
1427                         log_warning("Cannot add isolate job for unit %s, ignoring: %s", u->meta.id, strerror(-r));
1428         }
1429
1430         return 0;
1431 }
1432
1433 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, DBusError *e, Job **_ret) {
1434         int r;
1435         Job *ret;
1436
1437         assert(m);
1438         assert(type < _JOB_TYPE_MAX);
1439         assert(unit);
1440         assert(mode < _JOB_MODE_MAX);
1441
1442         if (mode == JOB_ISOLATE && type != JOB_START) {
1443                 dbus_set_error(e, BUS_ERROR_INVALID_JOB_MODE, "Isolate is only valid for start.");
1444                 return -EINVAL;
1445         }
1446
1447         log_debug("Trying to enqueue job %s/%s", unit->meta.id, job_type_to_string(type));
1448
1449         if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, e, &ret)) < 0) {
1450                 transaction_abort(m);
1451                 return r;
1452         }
1453
1454         if (mode == JOB_ISOLATE)
1455                 if ((r = transaction_add_isolate_jobs(m)) < 0) {
1456                         transaction_abort(m);
1457                         return r;
1458                 }
1459
1460         if ((r = transaction_activate(m, mode, e)) < 0)
1461                 return r;
1462
1463         log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id);
1464
1465         if (_ret)
1466                 *_ret = ret;
1467
1468         return 0;
1469 }
1470
1471 int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, DBusError *e, Job **_ret) {
1472         Unit *unit;
1473         int r;
1474
1475         assert(m);
1476         assert(type < _JOB_TYPE_MAX);
1477         assert(name);
1478         assert(mode < _JOB_MODE_MAX);
1479
1480         if ((r = manager_load_unit(m, name, NULL, NULL, &unit)) < 0)
1481                 return r;
1482
1483         return manager_add_job(m, type, unit, mode, override, e, _ret);
1484 }
1485
1486 Job *manager_get_job(Manager *m, uint32_t id) {
1487         assert(m);
1488
1489         return hashmap_get(m->jobs, UINT32_TO_PTR(id));
1490 }
1491
1492 Unit *manager_get_unit(Manager *m, const char *name) {
1493         assert(m);
1494         assert(name);
1495
1496         return hashmap_get(m->units, name);
1497 }
1498
1499 unsigned manager_dispatch_load_queue(Manager *m) {
1500         Meta *meta;
1501         unsigned n = 0;
1502
1503         assert(m);
1504
1505         /* Make sure we are not run recursively */
1506         if (m->dispatching_load_queue)
1507                 return 0;
1508
1509         m->dispatching_load_queue = true;
1510
1511         /* Dispatches the load queue. Takes a unit from the queue and
1512          * tries to load its data until the queue is empty */
1513
1514         while ((meta = m->load_queue)) {
1515                 assert(meta->in_load_queue);
1516
1517                 unit_load((Unit*) meta);
1518                 n++;
1519         }
1520
1521         m->dispatching_load_queue = false;
1522         return n;
1523 }
1524
1525 int manager_load_unit_prepare(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1526         Unit *ret;
1527         int r;
1528
1529         assert(m);
1530         assert(name || path);
1531
1532         /* This will prepare the unit for loading, but not actually
1533          * load anything from disk. */
1534
1535         if (path && !is_path(path)) {
1536                 dbus_set_error(e, BUS_ERROR_INVALID_PATH, "Path %s is not absolute.", path);
1537                 return -EINVAL;
1538         }
1539
1540         if (!name)
1541                 name = file_name_from_path(path);
1542
1543         if (!unit_name_is_valid(name)) {
1544                 dbus_set_error(e, BUS_ERROR_INVALID_NAME, "Unit name %s is not valid.", name);
1545                 return -EINVAL;
1546         }
1547
1548         if ((ret = manager_get_unit(m, name))) {
1549                 *_ret = ret;
1550                 return 1;
1551         }
1552
1553         if (!(ret = unit_new(m)))
1554                 return -ENOMEM;
1555
1556         if (path)
1557                 if (!(ret->meta.fragment_path = strdup(path))) {
1558                         unit_free(ret);
1559                         return -ENOMEM;
1560                 }
1561
1562         if ((r = unit_add_name(ret, name)) < 0) {
1563                 unit_free(ret);
1564                 return r;
1565         }
1566
1567         unit_add_to_load_queue(ret);
1568         unit_add_to_dbus_queue(ret);
1569         unit_add_to_gc_queue(ret);
1570
1571         if (_ret)
1572                 *_ret = ret;
1573
1574         return 0;
1575 }
1576
1577 int manager_load_unit(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1578         int r;
1579
1580         assert(m);
1581
1582         /* This will load the service information files, but not actually
1583          * start any services or anything. */
1584
1585         if ((r = manager_load_unit_prepare(m, name, path, e, _ret)) != 0)
1586                 return r;
1587
1588         manager_dispatch_load_queue(m);
1589
1590         if (_ret)
1591                 *_ret = unit_follow_merge(*_ret);
1592
1593         return 0;
1594 }
1595
1596 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1597         Iterator i;
1598         Job *j;
1599
1600         assert(s);
1601         assert(f);
1602
1603         HASHMAP_FOREACH(j, s->jobs, i)
1604                 job_dump(j, f, prefix);
1605 }
1606
1607 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1608         Iterator i;
1609         Unit *u;
1610         const char *t;
1611
1612         assert(s);
1613         assert(f);
1614
1615         HASHMAP_FOREACH_KEY(u, t, s->units, i)
1616                 if (u->meta.id == t)
1617                         unit_dump(u, f, prefix);
1618 }
1619
1620 void manager_clear_jobs(Manager *m) {
1621         Job *j;
1622
1623         assert(m);
1624
1625         transaction_abort(m);
1626
1627         while ((j = hashmap_first(m->jobs)))
1628                 job_free(j);
1629 }
1630
1631 unsigned manager_dispatch_run_queue(Manager *m) {
1632         Job *j;
1633         unsigned n = 0;
1634
1635         if (m->dispatching_run_queue)
1636                 return 0;
1637
1638         m->dispatching_run_queue = true;
1639
1640         while ((j = m->run_queue)) {
1641                 assert(j->installed);
1642                 assert(j->in_run_queue);
1643
1644                 job_run_and_invalidate(j);
1645                 n++;
1646         }
1647
1648         m->dispatching_run_queue = false;
1649         return n;
1650 }
1651
1652 unsigned manager_dispatch_dbus_queue(Manager *m) {
1653         Job *j;
1654         Meta *meta;
1655         unsigned n = 0;
1656
1657         assert(m);
1658
1659         if (m->dispatching_dbus_queue)
1660                 return 0;
1661
1662         m->dispatching_dbus_queue = true;
1663
1664         while ((meta = m->dbus_unit_queue)) {
1665                 assert(meta->in_dbus_queue);
1666
1667                 bus_unit_send_change_signal((Unit*) meta);
1668                 n++;
1669         }
1670
1671         while ((j = m->dbus_job_queue)) {
1672                 assert(j->in_dbus_queue);
1673
1674                 bus_job_send_change_signal(j);
1675                 n++;
1676         }
1677
1678         m->dispatching_dbus_queue = false;
1679         return n;
1680 }
1681
1682 static int manager_process_notify_fd(Manager *m) {
1683         ssize_t n;
1684
1685         assert(m);
1686
1687         for (;;) {
1688                 char buf[4096];
1689                 struct msghdr msghdr;
1690                 struct iovec iovec;
1691                 struct ucred *ucred;
1692                 union {
1693                         struct cmsghdr cmsghdr;
1694                         uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
1695                 } control;
1696                 Unit *u;
1697                 char **tags;
1698
1699                 zero(iovec);
1700                 iovec.iov_base = buf;
1701                 iovec.iov_len = sizeof(buf)-1;
1702
1703                 zero(control);
1704                 zero(msghdr);
1705                 msghdr.msg_iov = &iovec;
1706                 msghdr.msg_iovlen = 1;
1707                 msghdr.msg_control = &control;
1708                 msghdr.msg_controllen = sizeof(control);
1709
1710                 if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) <= 0) {
1711                         if (n >= 0)
1712                                 return -EIO;
1713
1714                         if (errno == EAGAIN)
1715                                 break;
1716
1717                         return -errno;
1718                 }
1719
1720                 if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
1721                     control.cmsghdr.cmsg_level != SOL_SOCKET ||
1722                     control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
1723                     control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
1724                         log_warning("Received notify message without credentials. Ignoring.");
1725                         continue;
1726                 }
1727
1728                 ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
1729
1730                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(ucred->pid))))
1731                         if (!(u = cgroup_unit_by_pid(m, ucred->pid))) {
1732                                 log_warning("Cannot find unit for notify message of PID %lu.", (unsigned long) ucred->pid);
1733                                 continue;
1734                         }
1735
1736                 assert((size_t) n < sizeof(buf));
1737                 buf[n] = 0;
1738                 if (!(tags = strv_split(buf, "\n\r")))
1739                         return -ENOMEM;
1740
1741                 log_debug("Got notification message for unit %s", u->meta.id);
1742
1743                 if (UNIT_VTABLE(u)->notify_message)
1744                         UNIT_VTABLE(u)->notify_message(u, ucred->pid, tags);
1745
1746                 strv_free(tags);
1747         }
1748
1749         return 0;
1750 }
1751
1752 static int manager_dispatch_sigchld(Manager *m) {
1753         assert(m);
1754
1755         for (;;) {
1756                 siginfo_t si;
1757                 Unit *u;
1758                 int r;
1759
1760                 zero(si);
1761
1762                 /* First we call waitd() for a PID and do not reap the
1763                  * zombie. That way we can still access /proc/$PID for
1764                  * it while it is a zombie. */
1765                 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1766
1767                         if (errno == ECHILD)
1768                                 break;
1769
1770                         if (errno == EINTR)
1771                                 continue;
1772
1773                         return -errno;
1774                 }
1775
1776                 if (si.si_pid <= 0)
1777                         break;
1778
1779                 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1780                         char *name = NULL;
1781
1782                         get_process_name(si.si_pid, &name);
1783                         log_debug("Got SIGCHLD for process %lu (%s)", (unsigned long) si.si_pid, strna(name));
1784                         free(name);
1785                 }
1786
1787                 /* Let's flush any message the dying child might still
1788                  * have queued for us. This ensures that the process
1789                  * still exists in /proc so that we can figure out
1790                  * which cgroup and hence unit it belongs to. */
1791                 if ((r = manager_process_notify_fd(m)) < 0)
1792                         return r;
1793
1794                 /* And now figure out the unit this belongs to */
1795                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(si.si_pid))))
1796                         u = cgroup_unit_by_pid(m, si.si_pid);
1797
1798                 /* And now, we actually reap the zombie. */
1799                 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1800                         if (errno == EINTR)
1801                                 continue;
1802
1803                         return -errno;
1804                 }
1805
1806                 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1807                         continue;
1808
1809                 log_debug("Child %lu died (code=%s, status=%i/%s)",
1810                           (long unsigned) si.si_pid,
1811                           sigchld_code_to_string(si.si_code),
1812                           si.si_status,
1813                           strna(si.si_code == CLD_EXITED ? exit_status_to_string(si.si_status) : signal_to_string(si.si_status)));
1814
1815                 if (!u)
1816                         continue;
1817
1818                 log_debug("Child %lu belongs to %s", (long unsigned) si.si_pid, u->meta.id);
1819
1820                 hashmap_remove(m->watch_pids, LONG_TO_PTR(si.si_pid));
1821                 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1822         }
1823
1824         return 0;
1825 }
1826
1827 static int manager_start_target(Manager *m, const char *name, JobMode mode) {
1828         int r;
1829         DBusError error;
1830
1831         dbus_error_init(&error);
1832
1833         log_info("Activating special unit %s", name);
1834
1835         if ((r = manager_add_job_by_name(m, JOB_START, name, mode, true, &error, NULL)) < 0)
1836                 log_error("Failed to enqueue %s job: %s", name, bus_error(&error, r));
1837
1838         dbus_error_free(&error);
1839
1840         return r;
1841 }
1842
1843 static int manager_process_signal_fd(Manager *m) {
1844         ssize_t n;
1845         struct signalfd_siginfo sfsi;
1846         bool sigchld = false;
1847
1848         assert(m);
1849
1850         for (;;) {
1851                 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1852
1853                         if (n >= 0)
1854                                 return -EIO;
1855
1856                         if (errno == EAGAIN)
1857                                 break;
1858
1859                         return -errno;
1860                 }
1861
1862                 log_debug("Received SIG%s", strna(signal_to_string(sfsi.ssi_signo)));
1863
1864                 switch (sfsi.ssi_signo) {
1865
1866                 case SIGCHLD:
1867                         sigchld = true;
1868                         break;
1869
1870                 case SIGTERM:
1871                         if (m->running_as == MANAGER_SYSTEM) {
1872                                 /* This is for compatibility with the
1873                                  * original sysvinit */
1874                                 m->exit_code = MANAGER_REEXECUTE;
1875                                 break;
1876                         }
1877
1878                         /* Fall through */
1879
1880                 case SIGINT:
1881                         if (m->running_as == MANAGER_SYSTEM) {
1882                                 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET, JOB_REPLACE);
1883                                 break;
1884                         }
1885
1886                         /* Run the exit target if there is one, if not, just exit. */
1887                         if (manager_start_target(m, SPECIAL_EXIT_SERVICE, JOB_REPLACE) < 0) {
1888                                 m->exit_code = MANAGER_EXIT;
1889                                 return 0;
1890                         }
1891
1892                         break;
1893
1894                 case SIGWINCH:
1895                         if (m->running_as == MANAGER_SYSTEM)
1896                                 manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE);
1897
1898                         /* This is a nop on non-init */
1899                         break;
1900
1901                 case SIGPWR:
1902                         if (m->running_as == MANAGER_SYSTEM)
1903                                 manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE);
1904
1905                         /* This is a nop on non-init */
1906                         break;
1907
1908                 case SIGUSR1: {
1909                         Unit *u;
1910
1911                         u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
1912
1913                         if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
1914                                 log_info("Trying to reconnect to bus...");
1915                                 bus_init(m);
1916                         }
1917
1918                         if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
1919                                 log_info("Loading D-Bus service...");
1920                                 manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE);
1921                         }
1922
1923                         break;
1924                 }
1925
1926                 case SIGUSR2: {
1927                         FILE *f;
1928                         char *dump = NULL;
1929                         size_t size;
1930
1931                         if (!(f = open_memstream(&dump, &size))) {
1932                                 log_warning("Failed to allocate memory stream.");
1933                                 break;
1934                         }
1935
1936                         manager_dump_units(m, f, "\t");
1937                         manager_dump_jobs(m, f, "\t");
1938
1939                         if (ferror(f)) {
1940                                 fclose(f);
1941                                 free(dump);
1942                                 log_warning("Failed to write status stream");
1943                                 break;
1944                         }
1945
1946                         fclose(f);
1947                         log_dump(LOG_INFO, dump);
1948                         free(dump);
1949
1950                         break;
1951                 }
1952
1953                 case SIGHUP:
1954                         m->exit_code = MANAGER_RELOAD;
1955                         break;
1956
1957                 default: {
1958                         static const char * const table[] = {
1959                                 [0] = SPECIAL_DEFAULT_TARGET,
1960                                 [1] = SPECIAL_RESCUE_TARGET,
1961                                 [2] = SPECIAL_EMERGENCY_TARGET,
1962                                 [3] = SPECIAL_HALT_TARGET,
1963                                 [4] = SPECIAL_POWEROFF_TARGET,
1964                                 [5] = SPECIAL_REBOOT_TARGET
1965                         };
1966
1967                         if ((int) sfsi.ssi_signo >= SIGRTMIN+0 &&
1968                             (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(table)) {
1969                                 manager_start_target(m, table[sfsi.ssi_signo - SIGRTMIN],
1970                                                      (sfsi.ssi_signo == 1 || sfsi.ssi_signo == 2) ? JOB_ISOLATE : JOB_REPLACE);
1971                                 break;
1972                         }
1973
1974                         log_warning("Got unhandled signal <%s>.", strna(signal_to_string(sfsi.ssi_signo)));
1975                 }
1976                 }
1977         }
1978
1979         if (sigchld)
1980                 return manager_dispatch_sigchld(m);
1981
1982         return 0;
1983 }
1984
1985 static int process_event(Manager *m, struct epoll_event *ev) {
1986         int r;
1987         Watch *w;
1988
1989         assert(m);
1990         assert(ev);
1991
1992         assert(w = ev->data.ptr);
1993
1994         switch (w->type) {
1995
1996         case WATCH_SIGNAL:
1997
1998                 /* An incoming signal? */
1999                 if (ev->events != EPOLLIN)
2000                         return -EINVAL;
2001
2002                 if ((r = manager_process_signal_fd(m)) < 0)
2003                         return r;
2004
2005                 break;
2006
2007         case WATCH_NOTIFY:
2008
2009                 /* An incoming daemon notification event? */
2010                 if (ev->events != EPOLLIN)
2011                         return -EINVAL;
2012
2013                 if ((r = manager_process_notify_fd(m)) < 0)
2014                         return r;
2015
2016                 break;
2017
2018         case WATCH_FD:
2019
2020                 /* Some fd event, to be dispatched to the units */
2021                 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
2022                 break;
2023
2024         case WATCH_TIMER: {
2025                 uint64_t v;
2026                 ssize_t k;
2027
2028                 /* Some timer event, to be dispatched to the units */
2029                 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
2030
2031                         if (k < 0 && (errno == EINTR || errno == EAGAIN))
2032                                 break;
2033
2034                         return k < 0 ? -errno : -EIO;
2035                 }
2036
2037                 UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
2038                 break;
2039         }
2040
2041         case WATCH_MOUNT:
2042                 /* Some mount table change, intended for the mount subsystem */
2043                 mount_fd_event(m, ev->events);
2044                 break;
2045
2046         case WATCH_UDEV:
2047                 /* Some notification from udev, intended for the device subsystem */
2048                 device_fd_event(m, ev->events);
2049                 break;
2050
2051         case WATCH_DBUS_WATCH:
2052                 bus_watch_event(m, w, ev->events);
2053                 break;
2054
2055         case WATCH_DBUS_TIMEOUT:
2056                 bus_timeout_event(m, w, ev->events);
2057                 break;
2058
2059         default:
2060                 assert_not_reached("Unknown epoll event type.");
2061         }
2062
2063         return 0;
2064 }
2065
2066 int manager_loop(Manager *m) {
2067         int r;
2068
2069         RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
2070
2071         assert(m);
2072         m->exit_code = MANAGER_RUNNING;
2073
2074         /* Release the path cache */
2075         set_free_free(m->unit_path_cache);
2076         m->unit_path_cache = NULL;
2077
2078         /* There might still be some zombies hanging around from
2079          * before we were exec()'ed. Leat's reap them */
2080         if ((r = manager_dispatch_sigchld(m)) < 0)
2081                 return r;
2082
2083         while (m->exit_code == MANAGER_RUNNING) {
2084                 struct epoll_event event;
2085                 int n;
2086
2087                 if (!ratelimit_test(&rl)) {
2088                         /* Yay, something is going seriously wrong, pause a little */
2089                         log_warning("Looping too fast. Throttling execution a little.");
2090                         sleep(1);
2091                 }
2092
2093                 if (manager_dispatch_load_queue(m) > 0)
2094                         continue;
2095
2096                 if (manager_dispatch_run_queue(m) > 0)
2097                         continue;
2098
2099                 if (bus_dispatch(m) > 0)
2100                         continue;
2101
2102                 if (manager_dispatch_cleanup_queue(m) > 0)
2103                         continue;
2104
2105                 if (manager_dispatch_gc_queue(m) > 0)
2106                         continue;
2107
2108                 if (manager_dispatch_dbus_queue(m) > 0)
2109                         continue;
2110
2111                 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
2112
2113                         if (errno == EINTR)
2114                                 continue;
2115
2116                         return -errno;
2117                 }
2118
2119                 assert(n == 1);
2120
2121                 if ((r = process_event(m, &event)) < 0)
2122                         return r;
2123         }
2124
2125         return m->exit_code;
2126 }
2127
2128 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
2129         char *n;
2130         Unit *u;
2131
2132         assert(m);
2133         assert(s);
2134         assert(_u);
2135
2136         if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
2137                 return -EINVAL;
2138
2139         if (!(n = bus_path_unescape(s+31)))
2140                 return -ENOMEM;
2141
2142         u = manager_get_unit(m, n);
2143         free(n);
2144
2145         if (!u)
2146                 return -ENOENT;
2147
2148         *_u = u;
2149
2150         return 0;
2151 }
2152
2153 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
2154         Job *j;
2155         unsigned id;
2156         int r;
2157
2158         assert(m);
2159         assert(s);
2160         assert(_j);
2161
2162         if (!startswith(s, "/org/freedesktop/systemd1/job/"))
2163                 return -EINVAL;
2164
2165         if ((r = safe_atou(s + 30, &id)) < 0)
2166                 return r;
2167
2168         if (!(j = manager_get_job(m, id)))
2169                 return -ENOENT;
2170
2171         *_j = j;
2172
2173         return 0;
2174 }
2175
2176 static bool manager_utmp_good(Manager *m) {
2177         int r;
2178
2179         assert(m);
2180
2181         if ((r = mount_path_is_mounted(m, _PATH_UTMPX)) <= 0) {
2182
2183                 if (r < 0)
2184                         log_warning("Failed to determine whether " _PATH_UTMPX " is mounted: %s", strerror(-r));
2185
2186                 return false;
2187         }
2188
2189         return true;
2190 }
2191
2192 void manager_write_utmp_reboot(Manager *m) {
2193         int r;
2194
2195         assert(m);
2196
2197         if (m->utmp_reboot_written)
2198                 return;
2199
2200         if (m->running_as != MANAGER_SYSTEM)
2201                 return;
2202
2203         if (!manager_utmp_good(m))
2204                 return;
2205
2206         if ((r = utmp_put_reboot(m->startup_timestamp.realtime)) < 0) {
2207
2208                 if (r != -ENOENT && r != -EROFS)
2209                         log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
2210
2211                 return;
2212         }
2213
2214         m->utmp_reboot_written = true;
2215 }
2216
2217 void manager_write_utmp_runlevel(Manager *m, Unit *u) {
2218         int runlevel, r;
2219
2220         assert(m);
2221         assert(u);
2222
2223         if (u->meta.type != UNIT_TARGET)
2224                 return;
2225
2226         if (m->running_as != MANAGER_SYSTEM)
2227                 return;
2228
2229         if (!manager_utmp_good(m))
2230                 return;
2231
2232         if ((runlevel = target_get_runlevel(TARGET(u))) <= 0)
2233                 return;
2234
2235         if ((r = utmp_put_runlevel(0, runlevel, 0)) < 0) {
2236
2237                 if (r != -ENOENT && r != -EROFS)
2238                         log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
2239         }
2240 }
2241
2242 void manager_dispatch_bus_name_owner_changed(
2243                 Manager *m,
2244                 const char *name,
2245                 const char* old_owner,
2246                 const char *new_owner) {
2247
2248         Unit *u;
2249
2250         assert(m);
2251         assert(name);
2252
2253         if (!(u = hashmap_get(m->watch_bus, name)))
2254                 return;
2255
2256         UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
2257 }
2258
2259 void manager_dispatch_bus_query_pid_done(
2260                 Manager *m,
2261                 const char *name,
2262                 pid_t pid) {
2263
2264         Unit *u;
2265
2266         assert(m);
2267         assert(name);
2268         assert(pid >= 1);
2269
2270         if (!(u = hashmap_get(m->watch_bus, name)))
2271                 return;
2272
2273         UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
2274 }
2275
2276 int manager_open_serialization(FILE **_f) {
2277         char *path;
2278         mode_t saved_umask;
2279         int fd;
2280         FILE *f;
2281
2282         assert(_f);
2283
2284         if (asprintf(&path, "/dev/shm/systemd-%u.dump-XXXXXX", (unsigned) getpid()) < 0)
2285                 return -ENOMEM;
2286
2287         saved_umask = umask(0077);
2288         fd = mkostemp(path, O_RDWR|O_CLOEXEC);
2289         umask(saved_umask);
2290
2291         if (fd < 0) {
2292                 free(path);
2293                 return -errno;
2294         }
2295
2296         unlink(path);
2297
2298         log_debug("Serializing state to %s", path);
2299         free(path);
2300
2301         if (!(f = fdopen(fd, "w+")) < 0)
2302                 return -errno;
2303
2304         *_f = f;
2305
2306         return 0;
2307 }
2308
2309 int manager_serialize(Manager *m, FILE *f, FDSet *fds) {
2310         Iterator i;
2311         Unit *u;
2312         const char *t;
2313         int r;
2314
2315         assert(m);
2316         assert(f);
2317         assert(fds);
2318
2319         HASHMAP_FOREACH_KEY(u, t, m->units, i) {
2320                 if (u->meta.id != t)
2321                         continue;
2322
2323                 if (!unit_can_serialize(u))
2324                         continue;
2325
2326                 /* Start marker */
2327                 fputs(u->meta.id, f);
2328                 fputc('\n', f);
2329
2330                 if ((r = unit_serialize(u, f, fds)) < 0)
2331                         return r;
2332         }
2333
2334         if (ferror(f))
2335                 return -EIO;
2336
2337         return 0;
2338 }
2339
2340 int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
2341         int r = 0;
2342
2343         assert(m);
2344         assert(f);
2345
2346         log_debug("Deserializing state...");
2347
2348         m->n_deserializing ++;
2349
2350         for (;;) {
2351                 Unit *u;
2352                 char name[UNIT_NAME_MAX+2];
2353
2354                 /* Start marker */
2355                 if (!fgets(name, sizeof(name), f)) {
2356                         if (feof(f))
2357                                 break;
2358
2359                         r = -errno;
2360                         goto finish;
2361                 }
2362
2363                 char_array_0(name);
2364
2365                 if ((r = manager_load_unit(m, strstrip(name), NULL, NULL, &u)) < 0)
2366                         goto finish;
2367
2368                 if ((r = unit_deserialize(u, f, fds)) < 0)
2369                         goto finish;
2370         }
2371
2372         if (ferror(f)) {
2373                 r = -EIO;
2374                 goto finish;
2375         }
2376
2377         r = 0;
2378
2379 finish:
2380         assert(m->n_deserializing > 0);
2381         m->n_deserializing --;
2382
2383         return r;
2384 }
2385
2386 int manager_reload(Manager *m) {
2387         int r, q;
2388         FILE *f;
2389         FDSet *fds;
2390
2391         assert(m);
2392
2393         if ((r = manager_open_serialization(&f)) < 0)
2394                 return r;
2395
2396         if (!(fds = fdset_new())) {
2397                 r = -ENOMEM;
2398                 goto finish;
2399         }
2400
2401         if ((r = manager_serialize(m, f, fds)) < 0)
2402                 goto finish;
2403
2404         if (fseeko(f, 0, SEEK_SET) < 0) {
2405                 r = -errno;
2406                 goto finish;
2407         }
2408
2409         /* From here on there is no way back. */
2410         manager_clear_jobs_and_units(m);
2411
2412         /* Find new unit paths */
2413         lookup_paths_free(&m->lookup_paths);
2414         if ((q = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
2415                 r = q;
2416
2417         m->n_deserializing ++;
2418
2419         /* First, enumerate what we can from all config files */
2420         if ((q = manager_enumerate(m)) < 0)
2421                 r = q;
2422
2423         /* Second, deserialize our stored data */
2424         if ((q = manager_deserialize(m, f, fds)) < 0)
2425                 r = q;
2426
2427         fclose(f);
2428         f = NULL;
2429
2430         /* Third, fire things up! */
2431         if ((q = manager_coldplug(m)) < 0)
2432                 r = q;
2433
2434         assert(m->n_deserializing > 0);
2435         m->n_deserializing ++;
2436
2437 finish:
2438         if (f)
2439                 fclose(f);
2440
2441         if (fds)
2442                 fdset_free(fds);
2443
2444         return r;
2445 }
2446
2447 bool manager_is_booting_or_shutting_down(Manager *m) {
2448         Unit *u;
2449
2450         assert(m);
2451
2452         /* Is the initial job still around? */
2453         if (manager_get_job(m, 1))
2454                 return true;
2455
2456         /* Is there a job for the shutdown target? */
2457         if (((u = manager_get_unit(m, SPECIAL_SHUTDOWN_TARGET))))
2458                 return !!u->meta.job;
2459
2460         return false;
2461 }
2462
2463 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
2464         [MANAGER_SYSTEM] = "system",
2465         [MANAGER_SESSION] = "session"
2466 };
2467
2468 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);