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
  56 /* As soon as 16 units are in our GC queue, make sure to run a gc sweep */
  57 #define GC_QUEUE_ENTRIES_MAX 16
  58
  59 /* As soon as 5s passed since a unit was added to our GC queue, make sure to run a gc sweep */
  60 #define GC_QUEUE_USEC_MAX (10*USEC_PER_SEC)
  61
  62 static int enable_special_signals(Manager *m) {
  63         char fd;
  64
  65         assert(m);
  66
  67         /* Enable that we get SIGINT on control-alt-del */
  68         if (reboot(RB_DISABLE_CAD) < 0)
  69                 log_warning("Failed to enable ctrl-alt-del handling: %m");
  70
  71         if ((fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY)) < 0)
  72                 log_warning("Failed to open /dev/tty0: %m");
  73         else {
  74                 /* Enable that we get SIGWINCH on kbrequest */
  75                 if (ioctl(fd, KDSIGACCEPT, SIGWINCH) < 0)
  76                         log_warning("Failed to enable kbrequest handling: %s", strerror(errno));
  77
  78                 close_nointr_nofail(fd);
  79         }
  80
  81         return 0;
  82 }
  83
  84 static int manager_setup_signals(Manager *m) {
  85         sigset_t mask;
  86         struct epoll_event ev;
  87         struct sigaction sa;
  88
  89         assert(m);
  90
  91         /* We are not interested in SIGSTOP and friends. */
  92         zero(sa);
  93         sa.sa_handler = SIG_DFL;
  94         sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
  95         assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
  96
  97         assert_se(sigemptyset(&mask) == 0);
  98         assert_se(sigaddset(&mask, SIGCHLD) == 0);
  99         assert_se(sigaddset(&mask, SIGTERM) == 0);
 100         assert_se(sigaddset(&mask, SIGHUP) == 0);
 101         assert_se(sigaddset(&mask, SIGUSR1) == 0);
 102         assert_se(sigaddset(&mask, SIGUSR2) == 0);
 103         assert_se(sigaddset(&mask, SIGINT) == 0);   /* Kernel sends us this on control-alt-del */
 104         assert_se(sigaddset(&mask, SIGWINCH) == 0); /* Kernel sends us this on kbrequest (alt-arrowup) */
 105         assert_se(sigaddset(&mask, SIGPWR) == 0);   /* Some kernel drivers and upsd send us this on power failure */
 106         assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
 107
 108         m->signal_watch.type = WATCH_SIGNAL;
 109         if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0)
 110                 return -errno;
 111
 112         zero(ev);
 113         ev.events = EPOLLIN;
 114         ev.data.ptr = &m->signal_watch;
 115
 116         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0)
 117                 return -errno;
 118
 119         if (m->running_as == MANAGER_INIT)
 120                 return enable_special_signals(m);
 121
 122         return 0;
 123 }
 124
 125 static char** session_dirs(void) {
 126         const char *home, *e;
 127         char *config_home = NULL, *data_home = NULL;
 128         char **config_dirs = NULL, **data_dirs = NULL;
 129         char **r = NULL, **t;
 130
 131         /* Implement the mechanisms defined in
 132          *
 133          * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html
 134          *
 135          * We look in both the config and the data dirs because we
 136          * want to encourage that distributors ship their unit files
 137          * as data, and allow overriding as configuration.
 138          */
 139
 140         home = getenv("HOME");
 141
 142         if ((e = getenv("XDG_CONFIG_HOME"))) {
 143                 if (asprintf(&config_home, "%s/systemd/session", e) < 0)
 144                         goto fail;
 145
 146         } else if (home) {
 147                 if (asprintf(&config_home, "%s/.config/systemd/session", home) < 0)
 148                         goto fail;
 149         }
 150
 151         if ((e = getenv("XDG_CONFIG_DIRS")))
 152                 if (!(config_dirs = strv_split(e, ":")))
 153                         goto fail;
 154
 155         /* We don't treat /etc/xdg/systemd here as the spec
 156          * suggests because we assume that that is a link to
 157          * /etc/systemd/ anyway. */
 158
 159         if ((e = getenv("XDG_DATA_HOME"))) {
 160                 if (asprintf(&data_home, "%s/systemd/session", e) < 0)
 161                         goto fail;
 162
 163         } else if (home) {
 164                 if (asprintf(&data_home, "%s/.local/share/systemd/session", home) < 0)
 165                         goto fail;
 166
 167                 /* There is really no need for two unit dirs in $HOME,
 168                  * except to be fully compliant with the XDG spec. We
 169                  * now try to link the two dirs, so that we can
 170                  * minimize disk seeks a little. Further down we'll
 171                  * then filter out this link, if it is actually is
 172                  * one. */
 173
 174                 mkdir_parents(data_home, 0777);
 175                 symlink("../../../.config/systemd/session", data_home);
 176         }
 177
 178         if ((e = getenv("XDG_DATA_DIRS")))
 179                 data_dirs = strv_split(e, ":");
 180         else
 181                 data_dirs = strv_new("/usr/local/share", "/usr/share", NULL);
 182
 183         if (!data_dirs)
 184                 goto fail;
 185
 186         /* Now merge everything we found. */
 187         if (config_home) {
 188                 if (!(t = strv_append(r, config_home)))
 189                         goto fail;
 190                 strv_free(r);
 191                 r = t;
 192         }
 193
 194         if (!(t = strv_merge_concat(r, config_dirs, "/systemd/session")))
 195                 goto finish;
 196         strv_free(r);
 197         r = t;
 198
 199         if (!(t = strv_append(r, SESSION_CONFIG_UNIT_PATH)))
 200                 goto fail;
 201         strv_free(r);
 202         r = t;
 203
 204         if (data_home) {
 205                 if (!(t = strv_append(r, data_home)))
 206                         goto fail;
 207                 strv_free(r);
 208                 r = t;
 209         }
 210
 211         if (!(t = strv_merge_concat(r, data_dirs, "/systemd/session")))
 212                 goto fail;
 213         strv_free(r);
 214         r = t;
 215
 216         if (!(t = strv_append(r, SESSION_DATA_UNIT_PATH)))
 217                 goto fail;
 218         strv_free(r);
 219         r = t;
 220
 221         if (!strv_path_make_absolute_cwd(r))
 222             goto fail;
 223
 224 finish:
 225         free(config_home);
 226         strv_free(config_dirs);
 227         free(data_home);
 228         strv_free(data_dirs);
 229
 230         return r;
 231
 232 fail:
 233         strv_free(r);
 234         r = NULL;
 235         goto finish;
 236 }
 237
 238 static int manager_find_paths(Manager *m) {
 239         const char *e;
 240         char *t;
 241
 242         assert(m);
 243
 244         /* First priority is whatever has been passed to us via env
 245          * vars */
 246         if ((e = getenv("SYSTEMD_UNIT_PATH")))
 247                 if (!(m->unit_path = split_path_and_make_absolute(e)))
 248                         return -ENOMEM;
 249
 250         if (strv_isempty(m->unit_path)) {
 251
 252                 /* Nothing is set, so let's figure something out. */
 253                 strv_free(m->unit_path);
 254
 255                 if (m->running_as == MANAGER_SESSION) {
 256                         if (!(m->unit_path = session_dirs()))
 257                                 return -ENOMEM;
 258                 } else
 259                         if (!(m->unit_path = strv_new(
 260                                               SYSTEM_CONFIG_UNIT_PATH,  /* /etc/systemd/system/ */
 261                                               SYSTEM_DATA_UNIT_PATH,    /* /lib/systemd/system/ */
 262                                               NULL)))
 263                                 return -ENOMEM;
 264         }
 265
 266         if (m->running_as == MANAGER_INIT) {
 267                 /* /etc/init.d/ compatibility does not matter to users */
 268
 269                 if ((e = getenv("SYSTEMD_SYSVINIT_PATH")))
 270                         if (!(m->sysvinit_path = split_path_and_make_absolute(e)))
 271                                 return -ENOMEM;
 272
 273                 if (strv_isempty(m->sysvinit_path)) {
 274                         strv_free(m->sysvinit_path);
 275
 276                         if (!(m->sysvinit_path = strv_new(
 277                                               SYSTEM_SYSVINIT_PATH,     /* /etc/init.d/ */
 278                                               NULL)))
 279                                 return -ENOMEM;
 280                 }
 281
 282                 if ((e = getenv("SYSTEMD_SYSVRCND_PATH")))
 283                         if (!(m->sysvrcnd_path = split_path_and_make_absolute(e)))
 284                                 return -ENOMEM;
 285
 286                 if (strv_isempty(m->sysvrcnd_path)) {
 287                         strv_free(m->sysvrcnd_path);
 288
 289                         if (!(m->sysvrcnd_path = strv_new(
 290                                               SYSTEM_SYSVRCND_PATH,     /* /etc/rcN.d/ */
 291                                               NULL)))
 292                                 return -ENOMEM;
 293                 }
 294         }
 295
 296         if (m->unit_path)
 297                 if (!strv_path_canonicalize(m->unit_path))
 298                         return -ENOMEM;
 299
 300         if (m->sysvinit_path)
 301                 if (!strv_path_canonicalize(m->sysvinit_path))
 302                         return -ENOMEM;
 303
 304         if (m->sysvrcnd_path)
 305                 if (!strv_path_canonicalize(m->sysvrcnd_path))
 306                         return -ENOMEM;
 307
 308         strv_uniq(m->unit_path);
 309         strv_uniq(m->sysvinit_path);
 310         strv_uniq(m->sysvrcnd_path);
 311
 312         if (!strv_isempty(m->unit_path)) {
 313
 314                 if (!(t = strv_join(m->unit_path, "\n\t")))
 315                         return -ENOMEM;
 316                 log_debug("Looking for unit files in:\n\t%s", t);
 317                 free(t);
 318         } else {
 319                 log_debug("Ignoring unit files.");
 320                 strv_free(m->unit_path);
 321                 m->unit_path = NULL;
 322         }
 323
 324         if (!strv_isempty(m->sysvinit_path)) {
 325
 326                 if (!(t = strv_join(m->sysvinit_path, "\n\t")))
 327                         return -ENOMEM;
 328
 329                 log_debug("Looking for SysV init scripts in:\n\t%s", t);
 330                 free(t);
 331         } else {
 332                 log_debug("Ignoring SysV init scripts.");
 333                 strv_free(m->sysvinit_path);
 334                 m->sysvinit_path = NULL;
 335         }
 336
 337         if (!strv_isempty(m->sysvrcnd_path)) {
 338
 339                 if (!(t = strv_join(m->sysvrcnd_path, "\n\t")))
 340                         return -ENOMEM;
 341
 342                 log_debug("Looking for SysV rcN.d links in:\n\t%s", t);
 343                 free(t);
 344         } else {
 345                 log_debug("Ignoring SysV rcN.d links.");
 346                 strv_free(m->sysvrcnd_path);
 347                 m->sysvrcnd_path = NULL;
 348         }
 349
 350         return 0;
 351 }
 352
 353 int manager_new(ManagerRunningAs running_as, bool confirm_spawn, Manager **_m) {
 354         Manager *m;
 355         int r = -ENOMEM;
 356
 357         assert(_m);
 358         assert(running_as >= 0);
 359         assert(running_as < _MANAGER_RUNNING_AS_MAX);
 360
 361         if (!(m = new0(Manager, 1)))
 362                 return -ENOMEM;
 363
 364         timestamp_get(&m->startup_timestamp);
 365
 366         m->running_as = running_as;
 367         m->confirm_spawn = confirm_spawn;
 368         m->name_data_slot = -1;
 369         m->exit_code = _MANAGER_EXIT_CODE_INVALID;
 370
 371         m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_fd = -1;
 372         m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */
 373
 374         if (!(m->environment = strv_copy(environ)))
 375                 goto fail;
 376
 377         if (!(m->units = hashmap_new(string_hash_func, string_compare_func)))
 378                 goto fail;
 379
 380         if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 381                 goto fail;
 382
 383         if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 384                 goto fail;
 385
 386         if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
 387                 goto fail;
 388
 389         if (!(m->cgroup_bondings = hashmap_new(string_hash_func, string_compare_func)))
 390                 goto fail;
 391
 392         if (!(m->watch_bus = hashmap_new(string_hash_func, string_compare_func)))
 393                 goto fail;
 394
 395         if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
 396                 goto fail;
 397
 398         if ((r = manager_find_paths(m)) < 0)
 399                 goto fail;
 400
 401         if ((r = manager_setup_signals(m)) < 0)
 402                 goto fail;
 403
 404         if ((r = manager_setup_cgroup(m)) < 0)
 405                 goto fail;
 406
 407         /* Try to connect to the busses, if possible. */
 408         if ((r = bus_init_system(m)) < 0 ||
 409             (r = bus_init_api(m)) < 0)
 410                 goto fail;
 411
 412         *_m = m;
 413         return 0;
 414
 415 fail:
 416         manager_free(m);
 417         return r;
 418 }
 419
 420 static unsigned manager_dispatch_cleanup_queue(Manager *m) {
 421         Meta *meta;
 422         unsigned n = 0;
 423
 424         assert(m);
 425
 426         while ((meta = m->cleanup_queue)) {
 427                 assert(meta->in_cleanup_queue);
 428
 429                 unit_free(UNIT(meta));
 430                 n++;
 431         }
 432
 433         return n;
 434 }
 435
 436 enum {
 437         GC_OFFSET_IN_PATH,  /* This one is on the path we were travelling */
 438         GC_OFFSET_UNSURE,   /* No clue */
 439         GC_OFFSET_GOOD,     /* We still need this unit */
 440         GC_OFFSET_BAD,      /* We don't need this unit anymore */
 441         _GC_OFFSET_MAX
 442 };
 443
 444 static void unit_gc_sweep(Unit *u, unsigned gc_marker) {
 445         Iterator i;
 446         Unit *other;
 447         bool is_bad;
 448
 449         assert(u);
 450
 451         if (u->meta.gc_marker == gc_marker + GC_OFFSET_GOOD ||
 452             u->meta.gc_marker == gc_marker + GC_OFFSET_BAD ||
 453             u->meta.gc_marker == gc_marker + GC_OFFSET_IN_PATH)
 454                 return;
 455
 456         if (u->meta.in_cleanup_queue)
 457                 goto bad;
 458
 459         if (unit_check_gc(u))
 460                 goto good;
 461
 462         u->meta.gc_marker = gc_marker + GC_OFFSET_IN_PATH;
 463
 464         is_bad = true;
 465
 466         SET_FOREACH(other, u->meta.dependencies[UNIT_REFERENCED_BY], i) {
 467                 unit_gc_sweep(other, gc_marker);
 468
 469                 if (other->meta.gc_marker == gc_marker + GC_OFFSET_GOOD)
 470                         goto good;
 471
 472                 if (other->meta.gc_marker != gc_marker + GC_OFFSET_BAD)
 473                         is_bad = false;
 474         }
 475
 476         if (is_bad)
 477                 goto bad;
 478
 479         /* We were unable to find anything out about this entry, so
 480          * let's investigate it later */
 481         u->meta.gc_marker = gc_marker + GC_OFFSET_UNSURE;
 482         unit_add_to_gc_queue(u);
 483         return;
 484
 485 bad:
 486         /* We definitely know that this one is not useful anymore, so
 487          * let's mark it for deletion */
 488         u->meta.gc_marker = gc_marker + GC_OFFSET_BAD;
 489         unit_add_to_cleanup_queue(u);
 490         return;
 491
 492 good:
 493         u->meta.gc_marker = gc_marker + GC_OFFSET_GOOD;
 494 }
 495
 496 static unsigned manager_dispatch_gc_queue(Manager *m) {
 497         Meta *meta;
 498         unsigned n = 0;
 499         unsigned gc_marker;
 500
 501         assert(m);
 502
 503         if ((m->n_in_gc_queue < GC_QUEUE_ENTRIES_MAX) &&
 504             (m->gc_queue_timestamp <= 0 ||
 505              (m->gc_queue_timestamp + GC_QUEUE_USEC_MAX) > now(CLOCK_MONOTONIC)))
 506                 return 0;
 507
 508         log_debug("Running GC...");
 509
 510         m->gc_marker += _GC_OFFSET_MAX;
 511         if (m->gc_marker + _GC_OFFSET_MAX <= _GC_OFFSET_MAX)
 512                 m->gc_marker = 1;
 513
 514         gc_marker = m->gc_marker;
 515
 516         while ((meta = m->gc_queue)) {
 517                 assert(meta->in_gc_queue);
 518
 519                 unit_gc_sweep(UNIT(meta), gc_marker);
 520
 521                 LIST_REMOVE(Meta, gc_queue, m->gc_queue, meta);
 522                 meta->in_gc_queue = false;
 523
 524                 n++;
 525
 526                 if (meta->gc_marker == gc_marker + GC_OFFSET_BAD ||
 527                     meta->gc_marker == gc_marker + GC_OFFSET_UNSURE) {
 528                         log_debug("Collecting %s", meta->id);
 529                         meta->gc_marker = gc_marker + GC_OFFSET_BAD;
 530                         unit_add_to_cleanup_queue(UNIT(meta));
 531                 }
 532         }
 533
 534         m->n_in_gc_queue = 0;
 535         m->gc_queue_timestamp = 0;
 536
 537         return n;
 538 }
 539
 540 static void manager_clear_jobs_and_units(Manager *m) {
 541         Job *j;
 542         Unit *u;
 543
 544         assert(m);
 545
 546         manager_dispatch_cleanup_queue(m);
 547
 548         while ((j = hashmap_first(m->transaction_jobs)))
 549                 job_free(j);
 550
 551         while ((u = hashmap_first(m->units)))
 552                 unit_free(u);
 553 }
 554
 555 void manager_free(Manager *m) {
 556         UnitType c;
 557
 558         assert(m);
 559
 560         manager_clear_jobs_and_units(m);
 561
 562         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 563                 if (unit_vtable[c]->shutdown)
 564                         unit_vtable[c]->shutdown(m);
 565
 566         /* If we reexecute ourselves, we keep the root cgroup
 567          * around */
 568         manager_shutdown_cgroup(m, m->exit_code != MANAGER_REEXECUTE);
 569
 570         bus_done_api(m);
 571         bus_done_system(m);
 572
 573         hashmap_free(m->units);
 574         hashmap_free(m->jobs);
 575         hashmap_free(m->transaction_jobs);
 576         hashmap_free(m->watch_pids);
 577         hashmap_free(m->watch_bus);
 578
 579         if (m->epoll_fd >= 0)
 580                 close_nointr_nofail(m->epoll_fd);
 581         if (m->signal_watch.fd >= 0)
 582                 close_nointr_nofail(m->signal_watch.fd);
 583
 584         strv_free(m->unit_path);
 585         strv_free(m->sysvinit_path);
 586         strv_free(m->sysvrcnd_path);
 587         strv_free(m->environment);
 588
 589         free(m->cgroup_controller);
 590         free(m->cgroup_hierarchy);
 591
 592         hashmap_free(m->cgroup_bondings);
 593
 594         free(m);
 595 }
 596
 597 int manager_enumerate(Manager *m) {
 598         int r = 0, q;
 599         UnitType c;
 600
 601         assert(m);
 602
 603         /* Let's ask every type to load all units from disk/kernel
 604          * that it might know */
 605         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 606                 if (unit_vtable[c]->enumerate)
 607                         if ((q = unit_vtable[c]->enumerate(m)) < 0)
 608                                 r = q;
 609
 610         manager_dispatch_load_queue(m);
 611         return r;
 612 }
 613
 614 int manager_coldplug(Manager *m) {
 615         int r = 0, q;
 616         Iterator i;
 617         Unit *u;
 618         char *k;
 619
 620         assert(m);
 621
 622         /* Then, let's set up their initial state. */
 623         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
 624
 625                 /* ignore aliases */
 626                 if (u->meta.id != k)
 627                         continue;
 628
 629                 if ((q = unit_coldplug(u)) < 0)
 630                         r = q;
 631         }
 632
 633         return r;
 634 }
 635
 636 int manager_startup(Manager *m, FILE *serialization, FDSet *fds) {
 637         int r, q;
 638
 639         assert(m);
 640
 641         /* First, enumerate what we can from all config files */
 642         r = manager_enumerate(m);
 643
 644         /* Second, deserialize if there is something to deserialize */
 645         if (serialization)
 646                 if ((q = manager_deserialize(m, serialization, fds)) < 0)
 647                         r = q;
 648
 649         /* Third, fire things up! */
 650         if ((q = manager_coldplug(m)) < 0)
 651                 r = q;
 652
 653         /* Now that the initial devices are available, let's see if we
 654          * can write the utmp file */
 655         manager_write_utmp_reboot(m);
 656
 657         return r;
 658 }
 659
 660 static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) {
 661         assert(m);
 662         assert(j);
 663
 664         /* Deletes one job from the transaction */
 665
 666         manager_transaction_unlink_job(m, j, delete_dependencies);
 667
 668         if (!j->installed)
 669                 job_free(j);
 670 }
 671
 672 static void transaction_delete_unit(Manager *m, Unit *u) {
 673         Job *j;
 674
 675         /* Deletes all jobs associated with a certain unit from the
 676          * transaction */
 677
 678         while ((j = hashmap_get(m->transaction_jobs, u)))
 679                 transaction_delete_job(m, j, true);
 680 }
 681
 682 static void transaction_clean_dependencies(Manager *m) {
 683         Iterator i;
 684         Job *j;
 685
 686         assert(m);
 687
 688         /* Drops all dependencies of all installed jobs */
 689
 690         HASHMAP_FOREACH(j, m->jobs, i) {
 691                 while (j->subject_list)
 692                         job_dependency_free(j->subject_list);
 693                 while (j->object_list)
 694                         job_dependency_free(j->object_list);
 695         }
 696
 697         assert(!m->transaction_anchor);
 698 }
 699
 700 static void transaction_abort(Manager *m) {
 701         Job *j;
 702
 703         assert(m);
 704
 705         while ((j = hashmap_first(m->transaction_jobs)))
 706                 if (j->installed)
 707                         transaction_delete_job(m, j, true);
 708                 else
 709                         job_free(j);
 710
 711         assert(hashmap_isempty(m->transaction_jobs));
 712
 713         transaction_clean_dependencies(m);
 714 }
 715
 716 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
 717         JobDependency *l;
 718
 719         assert(m);
 720
 721         /* A recursive sweep through the graph that marks all units
 722          * that matter to the anchor job, i.e. are directly or
 723          * indirectly a dependency of the anchor job via paths that
 724          * are fully marked as mattering. */
 725
 726         if (j)
 727                 l = j->subject_list;
 728         else
 729                 l = m->transaction_anchor;
 730
 731         LIST_FOREACH(subject, l, l) {
 732
 733                 /* This link does not matter */
 734                 if (!l->matters)
 735                         continue;
 736
 737                 /* This unit has already been marked */
 738                 if (l->object->generation == generation)
 739                         continue;
 740
 741                 l->object->matters_to_anchor = true;
 742                 l->object->generation = generation;
 743
 744                 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
 745         }
 746 }
 747
 748 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
 749         JobDependency *l, *last;
 750
 751         assert(j);
 752         assert(other);
 753         assert(j->unit == other->unit);
 754         assert(!j->installed);
 755
 756         /* Merges 'other' into 'j' and then deletes j. */
 757
 758         j->type = t;
 759         j->state = JOB_WAITING;
 760         j->override = j->override || other->override;
 761
 762         j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
 763
 764         /* Patch us in as new owner of the JobDependency objects */
 765         last = NULL;
 766         LIST_FOREACH(subject, l, other->subject_list) {
 767                 assert(l->subject == other);
 768                 l->subject = j;
 769                 last = l;
 770         }
 771
 772         /* Merge both lists */
 773         if (last) {
 774                 last->subject_next = j->subject_list;
 775                 if (j->subject_list)
 776                         j->subject_list->subject_prev = last;
 777                 j->subject_list = other->subject_list;
 778         }
 779
 780         /* Patch us in as new owner of the JobDependency objects */
 781         last = NULL;
 782         LIST_FOREACH(object, l, other->object_list) {
 783                 assert(l->object == other);
 784                 l->object = j;
 785                 last = l;
 786         }
 787
 788         /* Merge both lists */
 789         if (last) {
 790                 last->object_next = j->object_list;
 791                 if (j->object_list)
 792                         j->object_list->object_prev = last;
 793                 j->object_list = other->object_list;
 794         }
 795
 796         /* Kill the other job */
 797         other->subject_list = NULL;
 798         other->object_list = NULL;
 799         transaction_delete_job(m, other, true);
 800 }
 801
 802 static int delete_one_unmergeable_job(Manager *m, Job *j) {
 803         Job *k;
 804
 805         assert(j);
 806
 807         /* Tries to delete one item in the linked list
 808          * j->transaction_next->transaction_next->... that conflicts
 809          * whith another one, in an attempt to make an inconsistent
 810          * transaction work. */
 811
 812         /* We rely here on the fact that if a merged with b does not
 813          * merge with c, either a or b merge with c neither */
 814         LIST_FOREACH(transaction, j, j)
 815                 LIST_FOREACH(transaction, k, j->transaction_next) {
 816                         Job *d;
 817
 818                         /* Is this one mergeable? Then skip it */
 819                         if (job_type_is_mergeable(j->type, k->type))
 820                                 continue;
 821
 822                         /* Ok, we found two that conflict, let's see if we can
 823                          * drop one of them */
 824                         if (!j->matters_to_anchor)
 825                                 d = j;
 826                         else if (!k->matters_to_anchor)
 827                                 d = k;
 828                         else
 829                                 return -ENOEXEC;
 830
 831                         /* Ok, we can drop one, so let's do so. */
 832                         log_debug("Trying to fix job merging by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type));
 833                         transaction_delete_job(m, d, true);
 834                         return 0;
 835                 }
 836
 837         return -EINVAL;
 838 }
 839
 840 static int transaction_merge_jobs(Manager *m) {
 841         Job *j;
 842         Iterator i;
 843         int r;
 844
 845         assert(m);
 846
 847         /* First step, check whether any of the jobs for one specific
 848          * task conflict. If so, try to drop one of them. */
 849         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 850                 JobType t;
 851                 Job *k;
 852
 853                 t = j->type;
 854                 LIST_FOREACH(transaction, k, j->transaction_next) {
 855                         if ((r = job_type_merge(&t, k->type)) >= 0)
 856                                 continue;
 857
 858                         /* OK, we could not merge all jobs for this
 859                          * action. Let's see if we can get rid of one
 860                          * of them */
 861
 862                         if ((r = delete_one_unmergeable_job(m, j)) >= 0)
 863                                 /* Ok, we managed to drop one, now
 864                                  * let's ask our callers to call us
 865                                  * again after garbage collecting */
 866                                 return -EAGAIN;
 867
 868                         /* We couldn't merge anything. Failure */
 869                         return r;
 870                 }
 871         }
 872
 873         /* Second step, merge the jobs. */
 874         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 875                 JobType t = j->type;
 876                 Job *k;
 877
 878                 /* Merge all transactions */
 879                 LIST_FOREACH(transaction, k, j->transaction_next)
 880                         assert_se(job_type_merge(&t, k->type) == 0);
 881
 882                 /* If an active job is mergeable, merge it too */
 883                 if (j->unit->meta.job)
 884                         job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
 885
 886                 while ((k = j->transaction_next)) {
 887                         if (j->installed) {
 888                                 transaction_merge_and_delete_job(m, k, j, t);
 889                                 j = k;
 890                         } else
 891                                 transaction_merge_and_delete_job(m, j, k, t);
 892                 }
 893
 894                 assert(!j->transaction_next);
 895                 assert(!j->transaction_prev);
 896         }
 897
 898         return 0;
 899 }
 900
 901 static void transaction_drop_redundant(Manager *m) {
 902         bool again;
 903
 904         assert(m);
 905
 906         /* Goes through the transaction and removes all jobs that are
 907          * a noop */
 908
 909         do {
 910                 Job *j;
 911                 Iterator i;
 912
 913                 again = false;
 914
 915                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 916                         bool changes_something = false;
 917                         Job *k;
 918
 919                         LIST_FOREACH(transaction, k, j) {
 920
 921                                 if (!job_is_anchor(k) &&
 922                                     job_type_is_redundant(k->type, unit_active_state(k->unit)))
 923                                         continue;
 924
 925                                 changes_something = true;
 926                                 break;
 927                         }
 928
 929                         if (changes_something)
 930                                 continue;
 931
 932                         log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type));
 933                         transaction_delete_job(m, j, false);
 934                         again = true;
 935                         break;
 936                 }
 937
 938         } while (again);
 939 }
 940
 941 static bool unit_matters_to_anchor(Unit *u, Job *j) {
 942         assert(u);
 943         assert(!j->transaction_prev);
 944
 945         /* Checks whether at least one of the jobs for this unit
 946          * matters to the anchor. */
 947
 948         LIST_FOREACH(transaction, j, j)
 949                 if (j->matters_to_anchor)
 950                         return true;
 951
 952         return false;
 953 }
 954
 955 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation) {
 956         Iterator i;
 957         Unit *u;
 958         int r;
 959
 960         assert(m);
 961         assert(j);
 962         assert(!j->transaction_prev);
 963
 964         /* Does a recursive sweep through the ordering graph, looking
 965          * for a cycle. If we find cycle we try to break it. */
 966
 967         /* Have we seen this before? */
 968         if (j->generation == generation) {
 969                 Job *k;
 970
 971                 /* If the marker is NULL we have been here already and
 972                  * decided the job was loop-free from here. Hence
 973                  * shortcut things and return right-away. */
 974                 if (!j->marker)
 975                         return 0;
 976
 977                 /* So, the marker is not NULL and we already have been
 978                  * here. We have a cycle. Let's try to break it. We go
 979                  * backwards in our path and try to find a suitable
 980                  * job to remove. We use the marker to find our way
 981                  * back, since smart how we are we stored our way back
 982                  * in there. */
 983                 log_debug("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type));
 984
 985                 for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) {
 986
 987                         log_debug("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 988
 989                         if (!k->installed &&
 990                             !unit_matters_to_anchor(k->unit, k)) {
 991                                 /* Ok, we can drop this one, so let's
 992                                  * do so. */
 993                                 log_debug("Breaking order cycle by deleting job %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 994                                 transaction_delete_unit(m, k->unit);
 995                                 return -EAGAIN;
 996                         }
 997
 998                         /* Check if this in fact was the beginning of
 999                          * the cycle */
1000                         if (k == j)
1001                                 break;
1002                 }
1003
1004                 log_debug("Unable to break cycle");
1005
1006                 return -ENOEXEC;
1007         }
1008
1009         /* Make the marker point to where we come from, so that we can
1010          * find our way backwards if we want to break a cycle. We use
1011          * a special marker for the beginning: we point to
1012          * ourselves. */
1013         j->marker = from ? from : j;
1014         j->generation = generation;
1015
1016         /* We assume that the the dependencies are bidirectional, and
1017          * hence can ignore UNIT_AFTER */
1018         SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
1019                 Job *o;
1020
1021                 /* Is there a job for this unit? */
1022                 if (!(o = hashmap_get(m->transaction_jobs, u)))
1023
1024                         /* Ok, there is no job for this in the
1025                          * transaction, but maybe there is already one
1026                          * running? */
1027                         if (!(o = u->meta.job))
1028                                 continue;
1029
1030                 if ((r = transaction_verify_order_one(m, o, j, generation)) < 0)
1031                         return r;
1032         }
1033
1034         /* Ok, let's backtrack, and remember that this entry is not on
1035          * our path anymore. */
1036         j->marker = NULL;
1037
1038         return 0;
1039 }
1040
1041 static int transaction_verify_order(Manager *m, unsigned *generation) {
1042         Job *j;
1043         int r;
1044         Iterator i;
1045         unsigned g;
1046
1047         assert(m);
1048         assert(generation);
1049
1050         /* Check if the ordering graph is cyclic. If it is, try to fix
1051          * that up by dropping one of the jobs. */
1052
1053         g = (*generation)++;
1054
1055         HASHMAP_FOREACH(j, m->transaction_jobs, i)
1056                 if ((r = transaction_verify_order_one(m, j, NULL, g)) < 0)
1057                         return r;
1058
1059         return 0;
1060 }
1061
1062 static void transaction_collect_garbage(Manager *m) {
1063         bool again;
1064
1065         assert(m);
1066
1067         /* Drop jobs that are not required by any other job */
1068
1069         do {
1070                 Iterator i;
1071                 Job *j;
1072
1073                 again = false;
1074
1075                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1076                         if (j->object_list)
1077                                 continue;
1078
1079                         log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type));
1080                         transaction_delete_job(m, j, true);
1081                         again = true;
1082                         break;
1083                 }
1084
1085         } while (again);
1086 }
1087
1088 static int transaction_is_destructive(Manager *m) {
1089         Iterator i;
1090         Job *j;
1091
1092         assert(m);
1093
1094         /* Checks whether applying this transaction means that
1095          * existing jobs would be replaced */
1096
1097         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1098
1099                 /* Assume merged */
1100                 assert(!j->transaction_prev);
1101                 assert(!j->transaction_next);
1102
1103                 if (j->unit->meta.job &&
1104                     j->unit->meta.job != j &&
1105                     !job_type_is_superset(j->type, j->unit->meta.job->type))
1106                         return -EEXIST;
1107         }
1108
1109         return 0;
1110 }
1111
1112 static void transaction_minimize_impact(Manager *m) {
1113         bool again;
1114         assert(m);
1115
1116         /* Drops all unnecessary jobs that reverse already active jobs
1117          * or that stop a running service. */
1118
1119         do {
1120                 Job *j;
1121                 Iterator i;
1122
1123                 again = false;
1124
1125                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1126                         LIST_FOREACH(transaction, j, j) {
1127                                 bool stops_running_service, changes_existing_job;
1128
1129                                 /* If it matters, we shouldn't drop it */
1130                                 if (j->matters_to_anchor)
1131                                         continue;
1132
1133                                 /* Would this stop a running service?
1134                                  * Would this change an existing job?
1135                                  * If so, let's drop this entry */
1136
1137                                 stops_running_service =
1138                                         j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
1139
1140                                 changes_existing_job =
1141                                         j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->state);
1142
1143                                 if (!stops_running_service && !changes_existing_job)
1144                                         continue;
1145
1146                                 if (stops_running_service)
1147                                         log_debug("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type));
1148
1149                                 if (changes_existing_job)
1150                                         log_debug("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type));
1151
1152                                 /* Ok, let's get rid of this */
1153                                 log_debug("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type));
1154
1155                                 transaction_delete_job(m, j, true);
1156                                 again = true;
1157                                 break;
1158                         }
1159
1160                         if (again)
1161                                 break;
1162                 }
1163
1164         } while (again);
1165 }
1166
1167 static int transaction_apply(Manager *m) {
1168         Iterator i;
1169         Job *j;
1170         int r;
1171
1172         /* Moves the transaction jobs to the set of active jobs */
1173
1174         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1175                 /* Assume merged */
1176                 assert(!j->transaction_prev);
1177                 assert(!j->transaction_next);
1178
1179                 if (j->installed)
1180                         continue;
1181
1182                 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
1183                         goto rollback;
1184         }
1185
1186         while ((j = hashmap_steal_first(m->transaction_jobs))) {
1187                 if (j->installed)
1188                         continue;
1189
1190                 if (j->unit->meta.job)
1191                         job_free(j->unit->meta.job);
1192
1193                 j->unit->meta.job = j;
1194                 j->installed = true;
1195
1196                 /* We're fully installed. Now let's free data we don't
1197                  * need anymore. */
1198
1199                 assert(!j->transaction_next);
1200                 assert(!j->transaction_prev);
1201
1202                 job_add_to_run_queue(j);
1203                 job_add_to_dbus_queue(j);
1204         }
1205
1206         /* As last step, kill all remaining job dependencies. */
1207         transaction_clean_dependencies(m);
1208
1209         return 0;
1210
1211 rollback:
1212
1213         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1214                 if (j->installed)
1215                         continue;
1216
1217                 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1218         }
1219
1220         return r;
1221 }
1222
1223 static int transaction_activate(Manager *m, JobMode mode) {
1224         int r;
1225         unsigned generation = 1;
1226
1227         assert(m);
1228
1229         /* This applies the changes recorded in transaction_jobs to
1230          * the actual list of jobs, if possible. */
1231
1232         /* First step: figure out which jobs matter */
1233         transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1234
1235         /* Second step: Try not to stop any running services if
1236          * we don't have to. Don't try to reverse running
1237          * jobs if we don't have to. */
1238         transaction_minimize_impact(m);
1239
1240         /* Third step: Drop redundant jobs */
1241         transaction_drop_redundant(m);
1242
1243         for (;;) {
1244                 /* Fourth step: Let's remove unneeded jobs that might
1245                  * be lurking. */
1246                 transaction_collect_garbage(m);
1247
1248                 /* Fifth step: verify order makes sense and correct
1249                  * cycles if necessary and possible */
1250                 if ((r = transaction_verify_order(m, &generation)) >= 0)
1251                         break;
1252
1253                 if (r != -EAGAIN) {
1254                         log_debug("Requested transaction contains an unfixable cyclic ordering dependency: %s", strerror(-r));
1255                         goto rollback;
1256                 }
1257
1258                 /* Let's see if the resulting transaction ordering
1259                  * graph is still cyclic... */
1260         }
1261
1262         for (;;) {
1263                 /* Sixth step: let's drop unmergeable entries if
1264                  * necessary and possible, merge entries we can
1265                  * merge */
1266                 if ((r = transaction_merge_jobs(m)) >= 0)
1267                         break;
1268
1269                 if (r != -EAGAIN) {
1270                         log_debug("Requested transaction contains unmergable jobs: %s", strerror(-r));
1271                         goto rollback;
1272                 }
1273
1274                 /* Seventh step: an entry got dropped, let's garbage
1275                  * collect its dependencies. */
1276                 transaction_collect_garbage(m);
1277
1278                 /* Let's see if the resulting transaction still has
1279                  * unmergeable entries ... */
1280         }
1281
1282         /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1283         transaction_drop_redundant(m);
1284
1285         /* Ninth step: check whether we can actually apply this */
1286         if (mode == JOB_FAIL)
1287                 if ((r = transaction_is_destructive(m)) < 0) {
1288                         log_debug("Requested transaction contradicts existing jobs: %s", strerror(-r));
1289                         goto rollback;
1290                 }
1291
1292         /* Tenth step: apply changes */
1293         if ((r = transaction_apply(m)) < 0) {
1294                 log_debug("Failed to apply transaction: %s", strerror(-r));
1295                 goto rollback;
1296         }
1297
1298         assert(hashmap_isempty(m->transaction_jobs));
1299         assert(!m->transaction_anchor);
1300
1301         return 0;
1302
1303 rollback:
1304         transaction_abort(m);
1305         return r;
1306 }
1307
1308 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1309         Job *j, *f;
1310         int r;
1311
1312         assert(m);
1313         assert(unit);
1314
1315         /* Looks for an axisting prospective job and returns that. If
1316          * it doesn't exist it is created and added to the prospective
1317          * jobs list. */
1318
1319         f = hashmap_get(m->transaction_jobs, unit);
1320
1321         LIST_FOREACH(transaction, j, f) {
1322                 assert(j->unit == unit);
1323
1324                 if (j->type == type) {
1325                         if (is_new)
1326                                 *is_new = false;
1327                         return j;
1328                 }
1329         }
1330
1331         if (unit->meta.job && unit->meta.job->type == type)
1332                 j = unit->meta.job;
1333         else if (!(j = job_new(m, type, unit)))
1334                 return NULL;
1335
1336         j->generation = 0;
1337         j->marker = NULL;
1338         j->matters_to_anchor = false;
1339         j->override = override;
1340
1341         LIST_PREPEND(Job, transaction, f, j);
1342
1343         if ((r = hashmap_replace(m->transaction_jobs, unit, f)) < 0) {
1344                 job_free(j);
1345                 return NULL;
1346         }
1347
1348         if (is_new)
1349                 *is_new = true;
1350
1351         log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1352
1353         return j;
1354 }
1355
1356 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1357         assert(m);
1358         assert(j);
1359
1360         if (j->transaction_prev)
1361                 j->transaction_prev->transaction_next = j->transaction_next;
1362         else if (j->transaction_next)
1363                 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1364         else
1365                 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1366
1367         if (j->transaction_next)
1368                 j->transaction_next->transaction_prev = j->transaction_prev;
1369
1370         j->transaction_prev = j->transaction_next = NULL;
1371
1372         while (j->subject_list)
1373                 job_dependency_free(j->subject_list);
1374
1375         while (j->object_list) {
1376                 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1377
1378                 job_dependency_free(j->object_list);
1379
1380                 if (other && delete_dependencies) {
1381                         log_debug("Deleting job %s/%s as dependency of job %s/%s",
1382                                   other->unit->meta.id, job_type_to_string(other->type),
1383                                   j->unit->meta.id, job_type_to_string(j->type));
1384                         transaction_delete_job(m, other, delete_dependencies);
1385                 }
1386         }
1387 }
1388
1389 static int transaction_add_job_and_dependencies(
1390                 Manager *m,
1391                 JobType type,
1392                 Unit *unit,
1393                 Job *by,
1394                 bool matters,
1395                 bool override,
1396                 Job **_ret) {
1397         Job *ret;
1398         Iterator i;
1399         Unit *dep;
1400         int r;
1401         bool is_new;
1402
1403         assert(m);
1404         assert(type < _JOB_TYPE_MAX);
1405         assert(unit);
1406
1407         if (unit->meta.load_state != UNIT_LOADED)
1408                 return -EINVAL;
1409
1410         if (!unit_job_is_applicable(unit, type))
1411                 return -EBADR;
1412
1413         /* First add the job. */
1414         if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1415                 return -ENOMEM;
1416
1417         /* Then, add a link to the job. */
1418         if (!job_dependency_new(by, ret, matters))
1419                 return -ENOMEM;
1420
1421         if (is_new) {
1422                 /* Finally, recursively add in all dependencies. */
1423                 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1424                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1425                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1426                                         goto fail;
1427
1428                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1429                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, NULL)) < 0 && r != -EBADR)
1430                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1431
1432                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1433                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, NULL)) < 0)
1434                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1435
1436                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1437                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1438                                         goto fail;
1439
1440                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1441                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, NULL)) < 0 && r != -EBADR)
1442                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1443
1444                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1445                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1446                                         goto fail;
1447
1448                 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1449
1450                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1451                                 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1452                                         goto fail;
1453                 }
1454
1455                 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1456         }
1457
1458         if (_ret)
1459                 *_ret = ret;
1460
1461         return 0;
1462
1463 fail:
1464         return r;
1465 }
1466
1467 static int transaction_add_isolate_jobs(Manager *m) {
1468         Iterator i;
1469         Unit *u;
1470         char *k;
1471         int r;
1472
1473         assert(m);
1474
1475         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
1476
1477                 /* ignore aliases */
1478                 if (u->meta.id != k)
1479                         continue;
1480
1481                 if (UNIT_VTABLE(u)->no_isolate)
1482                         continue;
1483
1484                 /* No need to stop inactive jobs */
1485                 if (unit_active_state(u) == UNIT_INACTIVE)
1486                         continue;
1487
1488                 /* Is there already something listed for this? */
1489                 if (hashmap_get(m->transaction_jobs, u))
1490                         continue;
1491
1492                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, u, NULL, true, false, NULL)) < 0)
1493                         log_warning("Cannot add isolate job for unit %s, ignoring: %s", u->meta.id, strerror(-r));
1494         }
1495
1496         return 0;
1497 }
1498
1499 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, Job **_ret) {
1500         int r;
1501         Job *ret;
1502
1503         assert(m);
1504         assert(type < _JOB_TYPE_MAX);
1505         assert(unit);
1506         assert(mode < _JOB_MODE_MAX);
1507
1508         if (mode == JOB_ISOLATE && type != JOB_START)
1509                 return -EINVAL;
1510
1511         log_debug("Trying to enqueue job %s/%s", unit->meta.id, job_type_to_string(type));
1512
1513         if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, &ret)) < 0) {
1514                 transaction_abort(m);
1515                 return r;
1516         }
1517
1518         if (mode == JOB_ISOLATE)
1519                 if ((r = transaction_add_isolate_jobs(m)) < 0) {
1520                         transaction_abort(m);
1521                         return r;
1522                 }
1523
1524         if ((r = transaction_activate(m, mode)) < 0)
1525                 return r;
1526
1527         log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id);
1528
1529         if (_ret)
1530                 *_ret = ret;
1531
1532         return 0;
1533 }
1534
1535 int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, Job **_ret) {
1536         Unit *unit;
1537         int r;
1538
1539         assert(m);
1540         assert(type < _JOB_TYPE_MAX);
1541         assert(name);
1542         assert(mode < _JOB_MODE_MAX);
1543
1544         if ((r = manager_load_unit(m, name, NULL, &unit)) < 0)
1545                 return r;
1546
1547         return manager_add_job(m, type, unit, mode, override, _ret);
1548 }
1549
1550 Job *manager_get_job(Manager *m, uint32_t id) {
1551         assert(m);
1552
1553         return hashmap_get(m->jobs, UINT32_TO_PTR(id));
1554 }
1555
1556 Unit *manager_get_unit(Manager *m, const char *name) {
1557         assert(m);
1558         assert(name);
1559
1560         return hashmap_get(m->units, name);
1561 }
1562
1563 unsigned manager_dispatch_load_queue(Manager *m) {
1564         Meta *meta;
1565         unsigned n = 0;
1566
1567         assert(m);
1568
1569         /* Make sure we are not run recursively */
1570         if (m->dispatching_load_queue)
1571                 return 0;
1572
1573         m->dispatching_load_queue = true;
1574
1575         /* Dispatches the load queue. Takes a unit from the queue and
1576          * tries to load its data until the queue is empty */
1577
1578         while ((meta = m->load_queue)) {
1579                 assert(meta->in_load_queue);
1580
1581                 unit_load(UNIT(meta));
1582                 n++;
1583         }
1584
1585         m->dispatching_load_queue = false;
1586         return n;
1587 }
1588
1589 int manager_load_unit_prepare(Manager *m, const char *name, const char *path, Unit **_ret) {
1590         Unit *ret;
1591         int r;
1592
1593         assert(m);
1594         assert(name || path);
1595
1596         /* This will prepare the unit for loading, but not actually
1597          * load anything from disk. */
1598
1599         if (path && !is_path(path))
1600                 return -EINVAL;
1601
1602         if (!name)
1603                 name = file_name_from_path(path);
1604
1605         if (!unit_name_is_valid(name))
1606                 return -EINVAL;
1607
1608         if ((ret = manager_get_unit(m, name))) {
1609                 *_ret = ret;
1610                 return 1;
1611         }
1612
1613         if (!(ret = unit_new(m)))
1614                 return -ENOMEM;
1615
1616         if (path)
1617                 if (!(ret->meta.fragment_path = strdup(path))) {
1618                         unit_free(ret);
1619                         return -ENOMEM;
1620                 }
1621
1622         if ((r = unit_add_name(ret, name)) < 0) {
1623                 unit_free(ret);
1624                 return r;
1625         }
1626
1627         unit_add_to_load_queue(ret);
1628         unit_add_to_dbus_queue(ret);
1629         unit_add_to_gc_queue(ret);
1630
1631         if (_ret)
1632                 *_ret = ret;
1633
1634         return 0;
1635 }
1636
1637 int manager_load_unit(Manager *m, const char *name, const char *path, Unit **_ret) {
1638         int r;
1639
1640         assert(m);
1641
1642         /* This will load the service information files, but not actually
1643          * start any services or anything. */
1644
1645         if ((r = manager_load_unit_prepare(m, name, path, _ret)) != 0)
1646                 return r;
1647
1648         manager_dispatch_load_queue(m);
1649
1650         if (_ret)
1651                 *_ret = unit_follow_merge(*_ret);
1652
1653         return 0;
1654 }
1655
1656 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1657         Iterator i;
1658         Job *j;
1659
1660         assert(s);
1661         assert(f);
1662
1663         HASHMAP_FOREACH(j, s->jobs, i)
1664                 job_dump(j, f, prefix);
1665 }
1666
1667 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1668         Iterator i;
1669         Unit *u;
1670         const char *t;
1671
1672         assert(s);
1673         assert(f);
1674
1675         HASHMAP_FOREACH_KEY(u, t, s->units, i)
1676                 if (u->meta.id == t)
1677                         unit_dump(u, f, prefix);
1678 }
1679
1680 void manager_clear_jobs(Manager *m) {
1681         Job *j;
1682
1683         assert(m);
1684
1685         transaction_abort(m);
1686
1687         while ((j = hashmap_first(m->jobs)))
1688                 job_free(j);
1689 }
1690
1691 unsigned manager_dispatch_run_queue(Manager *m) {
1692         Job *j;
1693         unsigned n = 0;
1694
1695         if (m->dispatching_run_queue)
1696                 return 0;
1697
1698         m->dispatching_run_queue = true;
1699
1700         while ((j = m->run_queue)) {
1701                 assert(j->installed);
1702                 assert(j->in_run_queue);
1703
1704                 job_run_and_invalidate(j);
1705                 n++;
1706         }
1707
1708         m->dispatching_run_queue = false;
1709         return n;
1710 }
1711
1712 unsigned manager_dispatch_dbus_queue(Manager *m) {
1713         Job *j;
1714         Meta *meta;
1715         unsigned n = 0;
1716
1717         assert(m);
1718
1719         if (m->dispatching_dbus_queue)
1720                 return 0;
1721
1722         m->dispatching_dbus_queue = true;
1723
1724         while ((meta = m->dbus_unit_queue)) {
1725                 assert(meta->in_dbus_queue);
1726
1727                 bus_unit_send_change_signal(UNIT(meta));
1728                 n++;
1729         }
1730
1731         while ((j = m->dbus_job_queue)) {
1732                 assert(j->in_dbus_queue);
1733
1734                 bus_job_send_change_signal(j);
1735                 n++;
1736         }
1737
1738         m->dispatching_dbus_queue = false;
1739         return n;
1740 }
1741
1742 static int manager_dispatch_sigchld(Manager *m) {
1743         assert(m);
1744
1745         for (;;) {
1746                 siginfo_t si;
1747                 Unit *u;
1748
1749                 zero(si);
1750
1751                 /* First we call waitd() for a PID and do not reap the
1752                  * zombie. That way we can still access /proc/$PID for
1753                  * it while it is a zombie. */
1754                 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1755
1756                         if (errno == ECHILD)
1757                                 break;
1758
1759                         if (errno == EINTR)
1760                                 continue;
1761
1762                         return -errno;
1763                 }
1764
1765                 if (si.si_pid <= 0)
1766                         break;
1767
1768                 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1769                         char *name = NULL;
1770
1771                         get_process_name(si.si_pid, &name);
1772                         log_debug("Got SIGCHLD for process %llu (%s)", (unsigned long long) si.si_pid, strna(name));
1773                         free(name);
1774                 }
1775
1776                 /* And now, we actually reap the zombie. */
1777                 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1778                         if (errno == EINTR)
1779                                 continue;
1780
1781                         return -errno;
1782                 }
1783
1784                 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1785                         continue;
1786
1787                 log_debug("Child %llu died (code=%s, status=%i/%s)",
1788                           (long long unsigned) si.si_pid,
1789                           sigchld_code_to_string(si.si_code),
1790                           si.si_status,
1791                           strna(si.si_code == CLD_EXITED ? exit_status_to_string(si.si_status) : strsignal(si.si_status)));
1792
1793                 if (!(u = hashmap_remove(m->watch_pids, UINT32_TO_PTR(si.si_pid))))
1794                         continue;
1795
1796                 log_debug("Child %llu belongs to %s", (long long unsigned) si.si_pid, u->meta.id);
1797
1798                 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1799         }
1800
1801         return 0;
1802 }
1803
1804 static int manager_start_target(Manager *m, const char *name) {
1805         int r;
1806
1807         if ((r = manager_add_job_by_name(m, JOB_START, name, JOB_REPLACE, true, NULL)) < 0)
1808                 log_error("Failed to enqueue %s job: %s", name, strerror(-r));
1809
1810         return r;
1811 }
1812
1813 static int manager_process_signal_fd(Manager *m) {
1814         ssize_t n;
1815         struct signalfd_siginfo sfsi;
1816         bool sigchld = false;
1817
1818         assert(m);
1819
1820         for (;;) {
1821                 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1822
1823                         if (n >= 0)
1824                                 return -EIO;
1825
1826                         if (errno == EAGAIN)
1827                                 break;
1828
1829                         return -errno;
1830                 }
1831
1832                 switch (sfsi.ssi_signo) {
1833
1834                 case SIGCHLD:
1835                         sigchld = true;
1836                         break;
1837
1838                 case SIGTERM:
1839                         if (m->running_as == MANAGER_INIT) {
1840                                 /* This is for compatibility with the
1841                                  * original sysvinit */
1842                                 m->exit_code = MANAGER_REEXECUTE;
1843                                 break;
1844                         }
1845
1846                         /* Fall through */
1847
1848                 case SIGINT:
1849                         if (m->running_as == MANAGER_INIT) {
1850                                 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET);
1851                                 break;
1852                         }
1853
1854                         /* Run the exit target if there is one, if not, just exit. */
1855                         if (manager_start_target(m, SPECIAL_EXIT_SERVICE) < 0) {
1856                                 m->exit_code = MANAGER_EXIT;
1857                                 return 0;
1858                         }
1859
1860                         break;
1861
1862                 case SIGWINCH:
1863                         if (m->running_as == MANAGER_INIT)
1864                                 manager_start_target(m, SPECIAL_KBREQUEST_TARGET);
1865
1866                         /* This is a nop on non-init */
1867                         break;
1868
1869                 case SIGPWR:
1870                         if (m->running_as == MANAGER_INIT)
1871                                 manager_start_target(m, SPECIAL_SIGPWR_TARGET);
1872
1873                         /* This is a nop on non-init */
1874                         break;
1875
1876                 case SIGUSR1: {
1877                         Unit *u;
1878
1879                         u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
1880
1881                         if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
1882                                 log_info("Trying to reconnect to bus...");
1883                                 bus_init_system(m);
1884                                 bus_init_api(m);
1885                         }
1886
1887                         if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
1888                                 log_info("Loading D-Bus service...");
1889                                 manager_start_target(m, SPECIAL_DBUS_SERVICE);
1890                         }
1891
1892                         break;
1893                 }
1894
1895                 case SIGUSR2: {
1896                         FILE *f;
1897                         char *dump = NULL;
1898                         size_t size;
1899
1900                         if (!(f = open_memstream(&dump, &size))) {
1901                                 log_warning("Failed to allocate memory stream.");
1902                                 break;
1903                         }
1904
1905                         manager_dump_units(m, f, "\t");
1906                         manager_dump_jobs(m, f, "\t");
1907
1908                         if (ferror(f)) {
1909                                 fclose(f);
1910                                 free(dump);
1911                                 log_warning("Failed to write status stream");
1912                                 break;
1913                         }
1914
1915                         fclose(f);
1916                         log_dump(LOG_INFO, dump);
1917                         free(dump);
1918
1919                         break;
1920                 }
1921
1922                 case SIGHUP:
1923                         m->exit_code = MANAGER_RELOAD;
1924                         break;
1925
1926                 default:
1927                         log_info("Got unhandled signal <%s>.", strsignal(sfsi.ssi_signo));
1928                 }
1929         }
1930
1931         if (sigchld)
1932                 return manager_dispatch_sigchld(m);
1933
1934         return 0;
1935 }
1936
1937 static int process_event(Manager *m, struct epoll_event *ev) {
1938         int r;
1939         Watch *w;
1940
1941         assert(m);
1942         assert(ev);
1943
1944         assert(w = ev->data.ptr);
1945
1946         switch (w->type) {
1947
1948         case WATCH_SIGNAL:
1949
1950                 /* An incoming signal? */
1951                 if (ev->events != EPOLLIN)
1952                         return -EINVAL;
1953
1954                 if ((r = manager_process_signal_fd(m)) < 0)
1955                         return r;
1956
1957                 break;
1958
1959         case WATCH_FD:
1960
1961                 /* Some fd event, to be dispatched to the units */
1962                 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
1963                 break;
1964
1965         case WATCH_TIMER: {
1966                 uint64_t v;
1967                 ssize_t k;
1968
1969                 /* Some timer event, to be dispatched to the units */
1970                 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
1971
1972                         if (k < 0 && (errno == EINTR || errno == EAGAIN))
1973                                 break;
1974
1975                         return k < 0 ? -errno : -EIO;
1976                 }
1977
1978                 UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
1979                 break;
1980         }
1981
1982         case WATCH_MOUNT:
1983                 /* Some mount table change, intended for the mount subsystem */
1984                 mount_fd_event(m, ev->events);
1985                 break;
1986
1987         case WATCH_UDEV:
1988                 /* Some notification from udev, intended for the device subsystem */
1989                 device_fd_event(m, ev->events);
1990                 break;
1991
1992         case WATCH_DBUS_WATCH:
1993                 bus_watch_event(m, w, ev->events);
1994                 break;
1995
1996         case WATCH_DBUS_TIMEOUT:
1997                 bus_timeout_event(m, w, ev->events);
1998                 break;
1999
2000         default:
2001                 assert_not_reached("Unknown epoll event type.");
2002         }
2003
2004         return 0;
2005 }
2006
2007 int manager_loop(Manager *m) {
2008         int r;
2009
2010         RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
2011
2012         assert(m);
2013         m->exit_code = MANAGER_RUNNING;
2014
2015         /* There might still be some zombies hanging around from
2016          * before we were exec()'ed. Leat's reap them */
2017         if ((r = manager_dispatch_sigchld(m)) < 0)
2018                 return r;
2019
2020         while (m->exit_code == MANAGER_RUNNING) {
2021                 struct epoll_event event;
2022                 int n;
2023
2024                 if (!ratelimit_test(&rl)) {
2025                         /* Yay, something is going seriously wrong, pause a little */
2026                         log_warning("Looping too fast. Throttling execution a little.");
2027                         sleep(1);
2028                 }
2029
2030                 if (manager_dispatch_load_queue(m) > 0)
2031                         continue;
2032
2033                 if (manager_dispatch_run_queue(m) > 0)
2034                         continue;
2035
2036                 if (bus_dispatch(m) > 0)
2037                         continue;
2038
2039                 if (manager_dispatch_cleanup_queue(m) > 0)
2040                         continue;
2041
2042                 if (manager_dispatch_gc_queue(m) > 0)
2043                         continue;
2044
2045                 if (manager_dispatch_dbus_queue(m) > 0)
2046                         continue;
2047
2048                 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
2049
2050                         if (errno == EINTR)
2051                                 continue;
2052
2053                         return -errno;
2054                 }
2055
2056                 assert(n == 1);
2057
2058                 if ((r = process_event(m, &event)) < 0)
2059                         return r;
2060         }
2061
2062         return m->exit_code;
2063 }
2064
2065 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
2066         char *n;
2067         Unit *u;
2068
2069         assert(m);
2070         assert(s);
2071         assert(_u);
2072
2073         if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
2074                 return -EINVAL;
2075
2076         if (!(n = bus_path_unescape(s+31)))
2077                 return -ENOMEM;
2078
2079         u = manager_get_unit(m, n);
2080         free(n);
2081
2082         if (!u)
2083                 return -ENOENT;
2084
2085         *_u = u;
2086
2087         return 0;
2088 }
2089
2090 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
2091         Job *j;
2092         unsigned id;
2093         int r;
2094
2095         assert(m);
2096         assert(s);
2097         assert(_j);
2098
2099         if (!startswith(s, "/org/freedesktop/systemd1/job/"))
2100                 return -EINVAL;
2101
2102         if ((r = safe_atou(s + 30, &id)) < 0)
2103                 return r;
2104
2105         if (!(j = manager_get_job(m, id)))
2106                 return -ENOENT;
2107
2108         *_j = j;
2109
2110         return 0;
2111 }
2112
2113 static bool manager_utmp_good(Manager *m) {
2114         int r;
2115
2116         assert(m);
2117
2118         if ((r = mount_path_is_mounted(m, _PATH_UTMPX)) <= 0) {
2119
2120                 if (r < 0)
2121                         log_warning("Failed to determine whether " _PATH_UTMPX " is mounted: %s", strerror(-r));
2122
2123                 return false;
2124         }
2125
2126         return true;
2127 }
2128
2129 void manager_write_utmp_reboot(Manager *m) {
2130         int r;
2131
2132         assert(m);
2133
2134         if (m->utmp_reboot_written)
2135                 return;
2136
2137         if (m->running_as != MANAGER_INIT)
2138                 return;
2139
2140         if (!manager_utmp_good(m))
2141                 return;
2142
2143         if ((r = utmp_put_reboot(m->startup_timestamp.realtime)) < 0) {
2144
2145                 if (r != -ENOENT && r != -EROFS)
2146                         log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
2147
2148                 return;
2149         }
2150
2151         m->utmp_reboot_written = true;
2152 }
2153
2154 void manager_write_utmp_runlevel(Manager *m, Unit *u) {
2155         int runlevel, r;
2156
2157         assert(m);
2158         assert(u);
2159
2160         if (u->meta.type != UNIT_TARGET)
2161                 return;
2162
2163         if (m->running_as != MANAGER_INIT)
2164                 return;
2165
2166         if (!manager_utmp_good(m))
2167                 return;
2168
2169         if ((runlevel = target_get_runlevel(TARGET(u))) <= 0)
2170                 return;
2171
2172         if ((r = utmp_put_runlevel(0, runlevel, 0)) < 0) {
2173
2174                 if (r != -ENOENT && r != -EROFS)
2175                         log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
2176         }
2177 }
2178
2179 void manager_dispatch_bus_name_owner_changed(
2180                 Manager *m,
2181                 const char *name,
2182                 const char* old_owner,
2183                 const char *new_owner) {
2184
2185         Unit *u;
2186
2187         assert(m);
2188         assert(name);
2189
2190         if (!(u = hashmap_get(m->watch_bus, name)))
2191                 return;
2192
2193         UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
2194 }
2195
2196 void manager_dispatch_bus_query_pid_done(
2197                 Manager *m,
2198                 const char *name,
2199                 pid_t pid) {
2200
2201         Unit *u;
2202
2203         assert(m);
2204         assert(name);
2205         assert(pid >= 1);
2206
2207         if (!(u = hashmap_get(m->watch_bus, name)))
2208                 return;
2209
2210         UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
2211 }
2212
2213 int manager_open_serialization(FILE **_f) {
2214         char *path;
2215         mode_t saved_umask;
2216         int fd;
2217         FILE *f;
2218
2219         assert(_f);
2220
2221         if (asprintf(&path, "/dev/shm/systemd-%u.dump-XXXXXX", (unsigned) getpid()) < 0)
2222                 return -ENOMEM;
2223
2224         saved_umask = umask(0077);
2225         fd = mkostemp(path, O_RDWR|O_CLOEXEC);
2226         umask(saved_umask);
2227
2228         if (fd < 0) {
2229                 free(path);
2230                 return -errno;
2231         }
2232
2233         unlink(path);
2234
2235         log_debug("Serializing state to %s", path);
2236         free(path);
2237
2238         if (!(f = fdopen(fd, "w+")) < 0)
2239                 return -errno;
2240
2241         *_f = f;
2242
2243         return 0;
2244 }
2245
2246 int manager_serialize(Manager *m, FILE *f, FDSet *fds) {
2247         Iterator i;
2248         Unit *u;
2249         const char *t;
2250         int r;
2251
2252         assert(m);
2253         assert(f);
2254         assert(fds);
2255
2256         HASHMAP_FOREACH_KEY(u, t, m->units, i) {
2257                 if (u->meta.id != t)
2258                         continue;
2259
2260                 if (!unit_can_serialize(u))
2261                         continue;
2262
2263                 /* Start marker */
2264                 fputs(u->meta.id, f);
2265                 fputc('\n', f);
2266
2267                 if ((r = unit_serialize(u, f, fds)) < 0)
2268                         return r;
2269         }
2270
2271         if (ferror(f))
2272                 return -EIO;
2273
2274         return 0;
2275 }
2276
2277 int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
2278         int r = 0;
2279
2280         assert(m);
2281         assert(f);
2282
2283         log_debug("Deserializing state...");
2284
2285         for (;;) {
2286                 Unit *u;
2287                 char name[UNIT_NAME_MAX+2];
2288
2289                 /* Start marker */
2290                 if (!fgets(name, sizeof(name), f)) {
2291                         if (feof(f))
2292                                 break;
2293
2294                         return -errno;
2295                 }
2296
2297                 char_array_0(name);
2298
2299                 if ((r = manager_load_unit(m, strstrip(name), NULL, &u)) < 0)
2300                         return r;
2301
2302                 if ((r = unit_deserialize(u, f, fds)) < 0)
2303                         return r;
2304         }
2305
2306         if (ferror(f))
2307                 return -EIO;
2308
2309         return 0;
2310 }
2311
2312 int manager_reload(Manager *m) {
2313         int r, q;
2314         FILE *f;
2315         FDSet *fds;
2316
2317         assert(m);
2318
2319         if ((r = manager_open_serialization(&f)) < 0)
2320                 return r;
2321
2322         if (!(fds = fdset_new())) {
2323                 r = -ENOMEM;
2324                 goto finish;
2325         }
2326
2327         if ((r = manager_serialize(m, f, fds)) < 0)
2328                 goto finish;
2329
2330         if (fseeko(f, 0, SEEK_SET) < 0) {
2331                 r = -errno;
2332                 goto finish;
2333         }
2334
2335         /* From here on there is no way back. */
2336         manager_clear_jobs_and_units(m);
2337
2338         /* First, enumerate what we can from all config files */
2339         if ((q = manager_enumerate(m)) < 0)
2340                 r = q;
2341
2342         /* Second, deserialize our stored data */
2343         if ((q = manager_deserialize(m, f, fds)) < 0)
2344                 r = q;
2345
2346         fclose(f);
2347         f = NULL;
2348
2349         /* Third, fire things up! */
2350         if ((q = manager_coldplug(m)) < 0)
2351                 r = q;
2352
2353 finish:
2354         if (f)
2355                 fclose(f);
2356
2357         if (fds)
2358                 fdset_free(fds);
2359
2360         return r;
2361 }
2362
2363 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
2364         [MANAGER_INIT] = "init",
2365         [MANAGER_SYSTEM] = "system",
2366         [MANAGER_SESSION] = "session"
2367 };
2368
2369 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);