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