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