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 <sys/poll.h>
  31 #include <sys/reboot.h>
  32 #include <sys/ioctl.h>
  33 #include <linux/kd.h>
  34 #include <termios.h>
  35 #include <fcntl.h>
  36 #include <sys/types.h>
  37 #include <sys/stat.h>
  38 #include <dirent.h>
  39 #include <libaudit.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 "unit-name.h"
  51 #include "dbus-unit.h"
  52 #include "dbus-job.h"
  53 #include "missing.h"
  54 #include "path-lookup.h"
  55 #include "special.h"
  56 #include "bus-errors.h"
  57
  58 /* As soon as 16 units are in our GC queue, make sure to run a gc sweep */
  59 #define GC_QUEUE_ENTRIES_MAX 16
  60
  61 /* As soon as 5s passed since a unit was added to our GC queue, make sure to run a gc sweep */
  62 #define GC_QUEUE_USEC_MAX (10*USEC_PER_SEC)
  63
  64 /* Where clients shall send notification messages to */
  65 #define NOTIFY_SOCKET "/org/freedesktop/systemd1/notify"
  66
  67 static int manager_setup_notify(Manager *m) {
  68         union {
  69                 struct sockaddr sa;
  70                 struct sockaddr_un un;
  71         } sa;
  72         struct epoll_event ev;
  73         int one = 1;
  74
  75         assert(m);
  76
  77         m->notify_watch.type = WATCH_NOTIFY;
  78         if ((m->notify_watch.fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) {
  79                 log_error("Failed to allocate notification socket: %m");
  80                 return -errno;
  81         }
  82
  83         zero(sa);
  84         sa.sa.sa_family = AF_UNIX;
  85
  86         if (getpid() != 1)
  87                 snprintf(sa.un.sun_path+1, sizeof(sa.un.sun_path)-1, NOTIFY_SOCKET "/%llu", random_ull());
  88         else
  89                 strncpy(sa.un.sun_path+1, NOTIFY_SOCKET, sizeof(sa.un.sun_path)-1);
  90
  91         if (bind(m->notify_watch.fd, &sa.sa, sizeof(sa_family_t) + 1 + strlen(sa.un.sun_path+1)) < 0) {
  92                 log_error("bind() failed: %m");
  93                 return -errno;
  94         }
  95
  96         if (setsockopt(m->notify_watch.fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)) < 0) {
  97                 log_error("SO_PASSCRED failed: %m");
  98                 return -errno;
  99         }
 100
 101         zero(ev);
 102         ev.events = EPOLLIN;
 103         ev.data.ptr = &m->notify_watch;
 104
 105         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->notify_watch.fd, &ev) < 0)
 106                 return -errno;
 107
 108         if (!(m->notify_socket = strdup(sa.un.sun_path+1)))
 109                 return -ENOMEM;
 110
 111         return 0;
 112 }
 113
 114 static int enable_special_signals(Manager *m) {
 115         char fd;
 116
 117         assert(m);
 118
 119         /* Enable that we get SIGINT on control-alt-del */
 120         if (reboot(RB_DISABLE_CAD) < 0)
 121                 log_warning("Failed to enable ctrl-alt-del handling: %m");
 122
 123         if ((fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY)) < 0)
 124                 log_warning("Failed to open /dev/tty0: %m");
 125         else {
 126                 /* Enable that we get SIGWINCH on kbrequest */
 127                 if (ioctl(fd, KDSIGACCEPT, SIGWINCH) < 0)
 128                         log_warning("Failed to enable kbrequest handling: %s", strerror(errno));
 129
 130                 close_nointr_nofail(fd);
 131         }
 132
 133         return 0;
 134 }
 135
 136 static int manager_setup_signals(Manager *m) {
 137         sigset_t mask;
 138         struct epoll_event ev;
 139         struct sigaction sa;
 140
 141         assert(m);
 142
 143         /* We are not interested in SIGSTOP and friends. */
 144         zero(sa);
 145         sa.sa_handler = SIG_DFL;
 146         sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
 147         assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
 148
 149         assert_se(sigemptyset(&mask) == 0);
 150
 151         sigset_add_many(&mask,
 152                         SIGCHLD,     /* Child died */
 153                         SIGTERM,     /* Reexecute daemon */
 154                         SIGHUP,      /* Reload configuration */
 155                         SIGUSR1,     /* systemd/upstart: reconnect to D-Bus */
 156                         SIGUSR2,     /* systemd: dump status */
 157                         SIGINT,      /* Kernel sends us this on control-alt-del */
 158                         SIGWINCH,    /* Kernel sends us this on kbrequest (alt-arrowup) */
 159                         SIGPWR,      /* Some kernel drivers and upsd send us this on power failure */
 160                         SIGRTMIN+0,  /* systemd: start default.target */
 161                         SIGRTMIN+1,  /* systemd: start rescue.target */
 162                         SIGRTMIN+2,  /* systemd: isolate emergency.target */
 163                         SIGRTMIN+3,  /* systemd: start halt.target */
 164                         SIGRTMIN+4,  /* systemd: start poweroff.target */
 165                         SIGRTMIN+5,  /* systemd: start reboot.target */
 166                         -1);
 167         assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
 168
 169         m->signal_watch.type = WATCH_SIGNAL;
 170         if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0)
 171                 return -errno;
 172
 173         zero(ev);
 174         ev.events = EPOLLIN;
 175         ev.data.ptr = &m->signal_watch;
 176
 177         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0)
 178                 return -errno;
 179
 180         if (m->running_as == MANAGER_SYSTEM)
 181                 return enable_special_signals(m);
 182
 183         return 0;
 184 }
 185
 186 int manager_new(ManagerRunningAs running_as, Manager **_m) {
 187         Manager *m;
 188         int r = -ENOMEM;
 189
 190         assert(_m);
 191         assert(running_as >= 0);
 192         assert(running_as < _MANAGER_RUNNING_AS_MAX);
 193
 194         if (!(m = new0(Manager, 1)))
 195                 return -ENOMEM;
 196
 197         dual_timestamp_get(&m->startup_timestamp);
 198
 199         m->running_as = running_as;
 200         m->name_data_slot = m->subscribed_data_slot = -1;
 201         m->exit_code = _MANAGER_EXIT_CODE_INVALID;
 202         m->pin_cgroupfs_fd = -1;
 203
 204 #ifdef HAVE_AUDIT
 205         m->audit_fd = -1;
 206 #endif
 207
 208         m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_fd = -1;
 209         m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */
 210
 211         if (!(m->environment = strv_copy(environ)))
 212                 goto fail;
 213
 214         if (!(m->units = hashmap_new(string_hash_func, string_compare_func)))
 215                 goto fail;
 216
 217         if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 218                 goto fail;
 219
 220         if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 221                 goto fail;
 222
 223         if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
 224                 goto fail;
 225
 226         if (!(m->cgroup_bondings = hashmap_new(string_hash_func, string_compare_func)))
 227                 goto fail;
 228
 229         if (!(m->watch_bus = hashmap_new(string_hash_func, string_compare_func)))
 230                 goto fail;
 231
 232         if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
 233                 goto fail;
 234
 235         if ((r = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
 236                 goto fail;
 237
 238         if ((r = manager_setup_signals(m)) < 0)
 239                 goto fail;
 240
 241         if ((r = manager_setup_cgroup(m)) < 0)
 242                 goto fail;
 243
 244         if ((r = manager_setup_notify(m)) < 0)
 245                 goto fail;
 246
 247         /* Try to connect to the busses, if possible. */
 248         if ((r = bus_init(m)) < 0)
 249                 goto fail;
 250
 251         if ((m->audit_fd = audit_open()) < 0)
 252                 log_error("Failed to connect to audit log: %m");
 253
 254         *_m = m;
 255         return 0;
 256
 257 fail:
 258         manager_free(m);
 259         return r;
 260 }
 261
 262 static unsigned manager_dispatch_cleanup_queue(Manager *m) {
 263         Meta *meta;
 264         unsigned n = 0;
 265
 266         assert(m);
 267
 268         while ((meta = m->cleanup_queue)) {
 269                 assert(meta->in_cleanup_queue);
 270
 271                 unit_free((Unit*) meta);
 272                 n++;
 273         }
 274
 275         return n;
 276 }
 277
 278 enum {
 279         GC_OFFSET_IN_PATH,  /* This one is on the path we were travelling */
 280         GC_OFFSET_UNSURE,   /* No clue */
 281         GC_OFFSET_GOOD,     /* We still need this unit */
 282         GC_OFFSET_BAD,      /* We don't need this unit anymore */
 283         _GC_OFFSET_MAX
 284 };
 285
 286 static void unit_gc_sweep(Unit *u, unsigned gc_marker) {
 287         Iterator i;
 288         Unit *other;
 289         bool is_bad;
 290
 291         assert(u);
 292
 293         if (u->meta.gc_marker == gc_marker + GC_OFFSET_GOOD ||
 294             u->meta.gc_marker == gc_marker + GC_OFFSET_BAD ||
 295             u->meta.gc_marker == gc_marker + GC_OFFSET_IN_PATH)
 296                 return;
 297
 298         if (u->meta.in_cleanup_queue)
 299                 goto bad;
 300
 301         if (unit_check_gc(u))
 302                 goto good;
 303
 304         u->meta.gc_marker = gc_marker + GC_OFFSET_IN_PATH;
 305
 306         is_bad = true;
 307
 308         SET_FOREACH(other, u->meta.dependencies[UNIT_REFERENCED_BY], i) {
 309                 unit_gc_sweep(other, gc_marker);
 310
 311                 if (other->meta.gc_marker == gc_marker + GC_OFFSET_GOOD)
 312                         goto good;
 313
 314                 if (other->meta.gc_marker != gc_marker + GC_OFFSET_BAD)
 315                         is_bad = false;
 316         }
 317
 318         if (is_bad)
 319                 goto bad;
 320
 321         /* We were unable to find anything out about this entry, so
 322          * let's investigate it later */
 323         u->meta.gc_marker = gc_marker + GC_OFFSET_UNSURE;
 324         unit_add_to_gc_queue(u);
 325         return;
 326
 327 bad:
 328         /* We definitely know that this one is not useful anymore, so
 329          * let's mark it for deletion */
 330         u->meta.gc_marker = gc_marker + GC_OFFSET_BAD;
 331         unit_add_to_cleanup_queue(u);
 332         return;
 333
 334 good:
 335         u->meta.gc_marker = gc_marker + GC_OFFSET_GOOD;
 336 }
 337
 338 static unsigned manager_dispatch_gc_queue(Manager *m) {
 339         Meta *meta;
 340         unsigned n = 0;
 341         unsigned gc_marker;
 342
 343         assert(m);
 344
 345         if ((m->n_in_gc_queue < GC_QUEUE_ENTRIES_MAX) &&
 346             (m->gc_queue_timestamp <= 0 ||
 347              (m->gc_queue_timestamp + GC_QUEUE_USEC_MAX) > now(CLOCK_MONOTONIC)))
 348                 return 0;
 349
 350         log_debug("Running GC...");
 351
 352         m->gc_marker += _GC_OFFSET_MAX;
 353         if (m->gc_marker + _GC_OFFSET_MAX <= _GC_OFFSET_MAX)
 354                 m->gc_marker = 1;
 355
 356         gc_marker = m->gc_marker;
 357
 358         while ((meta = m->gc_queue)) {
 359                 assert(meta->in_gc_queue);
 360
 361                 unit_gc_sweep((Unit*) meta, gc_marker);
 362
 363                 LIST_REMOVE(Meta, gc_queue, m->gc_queue, meta);
 364                 meta->in_gc_queue = false;
 365
 366                 n++;
 367
 368                 if (meta->gc_marker == gc_marker + GC_OFFSET_BAD ||
 369                     meta->gc_marker == gc_marker + GC_OFFSET_UNSURE) {
 370                         log_debug("Collecting %s", meta->id);
 371                         meta->gc_marker = gc_marker + GC_OFFSET_BAD;
 372                         unit_add_to_cleanup_queue((Unit*) meta);
 373                 }
 374         }
 375
 376         m->n_in_gc_queue = 0;
 377         m->gc_queue_timestamp = 0;
 378
 379         return n;
 380 }
 381
 382 static void manager_clear_jobs_and_units(Manager *m) {
 383         Job *j;
 384         Unit *u;
 385
 386         assert(m);
 387
 388         while ((j = hashmap_first(m->transaction_jobs)))
 389                 job_free(j);
 390
 391         while ((u = hashmap_first(m->units)))
 392                 unit_free(u);
 393
 394         manager_dispatch_cleanup_queue(m);
 395
 396         assert(!m->load_queue);
 397         assert(!m->run_queue);
 398         assert(!m->dbus_unit_queue);
 399         assert(!m->dbus_job_queue);
 400         assert(!m->cleanup_queue);
 401         assert(!m->gc_queue);
 402
 403         assert(hashmap_isempty(m->transaction_jobs));
 404         assert(hashmap_isempty(m->jobs));
 405         assert(hashmap_isempty(m->units));
 406 }
 407
 408 void manager_free(Manager *m) {
 409         UnitType c;
 410
 411         assert(m);
 412
 413         manager_clear_jobs_and_units(m);
 414
 415         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 416                 if (unit_vtable[c]->shutdown)
 417                         unit_vtable[c]->shutdown(m);
 418
 419         /* If we reexecute ourselves, we keep the root cgroup
 420          * around */
 421         manager_shutdown_cgroup(m, m->exit_code != MANAGER_REEXECUTE);
 422
 423         bus_done(m);
 424
 425         hashmap_free(m->units);
 426         hashmap_free(m->jobs);
 427         hashmap_free(m->transaction_jobs);
 428         hashmap_free(m->watch_pids);
 429         hashmap_free(m->watch_bus);
 430
 431         if (m->epoll_fd >= 0)
 432                 close_nointr_nofail(m->epoll_fd);
 433         if (m->signal_watch.fd >= 0)
 434                 close_nointr_nofail(m->signal_watch.fd);
 435         if (m->notify_watch.fd >= 0)
 436                 close_nointr_nofail(m->notify_watch.fd);
 437
 438 #ifdef HAVE_AUDIT
 439         if (m->audit_fd >= 0)
 440                 audit_close(m->audit_fd);
 441 #endif
 442
 443         free(m->notify_socket);
 444
 445         lookup_paths_free(&m->lookup_paths);
 446         strv_free(m->environment);
 447
 448         hashmap_free(m->cgroup_bondings);
 449         set_free_free(m->unit_path_cache);
 450
 451         free(m);
 452 }
 453
 454 int manager_enumerate(Manager *m) {
 455         int r = 0, q;
 456         UnitType c;
 457
 458         assert(m);
 459
 460         /* Let's ask every type to load all units from disk/kernel
 461          * that it might know */
 462         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 463                 if (unit_vtable[c]->enumerate)
 464                         if ((q = unit_vtable[c]->enumerate(m)) < 0)
 465                                 r = q;
 466
 467         manager_dispatch_load_queue(m);
 468         return r;
 469 }
 470
 471 int manager_coldplug(Manager *m) {
 472         int r = 0, q;
 473         Iterator i;
 474         Unit *u;
 475         char *k;
 476
 477         assert(m);
 478
 479         /* Then, let's set up their initial state. */
 480         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
 481
 482                 /* ignore aliases */
 483                 if (u->meta.id != k)
 484                         continue;
 485
 486                 if ((q = unit_coldplug(u)) < 0)
 487                         r = q;
 488         }
 489
 490         return r;
 491 }
 492
 493 static void manager_build_unit_path_cache(Manager *m) {
 494         char **i;
 495         DIR *d = NULL;
 496         int r;
 497
 498         assert(m);
 499
 500         set_free_free(m->unit_path_cache);
 501
 502         if (!(m->unit_path_cache = set_new(string_hash_func, string_compare_func))) {
 503                 log_error("Failed to allocate unit path cache.");
 504                 return;
 505         }
 506
 507         /* This simply builds a list of files we know exist, so that
 508          * we don't always have to go to disk */
 509
 510         STRV_FOREACH(i, m->lookup_paths.unit_path) {
 511                 struct dirent *de;
 512
 513                 if (!(d = opendir(*i))) {
 514                         log_error("Failed to open directory: %m");
 515                         continue;
 516                 }
 517
 518                 while ((de = readdir(d))) {
 519                         char *p;
 520
 521                         if (ignore_file(de->d_name))
 522                                 continue;
 523
 524                         if (asprintf(&p, "%s/%s", streq(*i, "/") ? "" : *i, de->d_name) < 0) {
 525                                 r = -ENOMEM;
 526                                 goto fail;
 527                         }
 528
 529                         if ((r = set_put(m->unit_path_cache, p)) < 0) {
 530                                 free(p);
 531                                 goto fail;
 532                         }
 533                 }
 534
 535                 closedir(d);
 536                 d = NULL;
 537         }
 538
 539         return;
 540
 541 fail:
 542         log_error("Failed to build unit path cache: %s", strerror(-r));
 543
 544         set_free_free(m->unit_path_cache);
 545         m->unit_path_cache = NULL;
 546
 547         if (d)
 548                 closedir(d);
 549 }
 550
 551 int manager_startup(Manager *m, FILE *serialization, FDSet *fds) {
 552         int r, q;
 553
 554         assert(m);
 555
 556         manager_build_unit_path_cache(m);
 557
 558         /* If we will deserialize make sure that during enumeration
 559          * this is already known, so we increase the counter here
 560          * already */
 561         if (serialization)
 562                 m->n_deserializing ++;
 563
 564         /* First, enumerate what we can from all config files */
 565         r = manager_enumerate(m);
 566
 567         /* Second, deserialize if there is something to deserialize */
 568         if (serialization)
 569                 if ((q = manager_deserialize(m, serialization, fds)) < 0)
 570                         r = q;
 571
 572         /* Third, fire things up! */
 573         if ((q = manager_coldplug(m)) < 0)
 574                 r = q;
 575
 576         if (serialization) {
 577                 assert(m->n_deserializing > 0);
 578                 m->n_deserializing --;
 579         }
 580
 581         return r;
 582 }
 583
 584 static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) {
 585         assert(m);
 586         assert(j);
 587
 588         /* Deletes one job from the transaction */
 589
 590         manager_transaction_unlink_job(m, j, delete_dependencies);
 591
 592         if (!j->installed)
 593                 job_free(j);
 594 }
 595
 596 static void transaction_delete_unit(Manager *m, Unit *u) {
 597         Job *j;
 598
 599         /* Deletes all jobs associated with a certain unit from the
 600          * transaction */
 601
 602         while ((j = hashmap_get(m->transaction_jobs, u)))
 603                 transaction_delete_job(m, j, true);
 604 }
 605
 606 static void transaction_clean_dependencies(Manager *m) {
 607         Iterator i;
 608         Job *j;
 609
 610         assert(m);
 611
 612         /* Drops all dependencies of all installed jobs */
 613
 614         HASHMAP_FOREACH(j, m->jobs, i) {
 615                 while (j->subject_list)
 616                         job_dependency_free(j->subject_list);
 617                 while (j->object_list)
 618                         job_dependency_free(j->object_list);
 619         }
 620
 621         assert(!m->transaction_anchor);
 622 }
 623
 624 static void transaction_abort(Manager *m) {
 625         Job *j;
 626
 627         assert(m);
 628
 629         while ((j = hashmap_first(m->transaction_jobs)))
 630                 if (j->installed)
 631                         transaction_delete_job(m, j, true);
 632                 else
 633                         job_free(j);
 634
 635         assert(hashmap_isempty(m->transaction_jobs));
 636
 637         transaction_clean_dependencies(m);
 638 }
 639
 640 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
 641         JobDependency *l;
 642
 643         assert(m);
 644
 645         /* A recursive sweep through the graph that marks all units
 646          * that matter to the anchor job, i.e. are directly or
 647          * indirectly a dependency of the anchor job via paths that
 648          * are fully marked as mattering. */
 649
 650         if (j)
 651                 l = j->subject_list;
 652         else
 653                 l = m->transaction_anchor;
 654
 655         LIST_FOREACH(subject, l, l) {
 656
 657                 /* This link does not matter */
 658                 if (!l->matters)
 659                         continue;
 660
 661                 /* This unit has already been marked */
 662                 if (l->object->generation == generation)
 663                         continue;
 664
 665                 l->object->matters_to_anchor = true;
 666                 l->object->generation = generation;
 667
 668                 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
 669         }
 670 }
 671
 672 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
 673         JobDependency *l, *last;
 674
 675         assert(j);
 676         assert(other);
 677         assert(j->unit == other->unit);
 678         assert(!j->installed);
 679
 680         /* Merges 'other' into 'j' and then deletes j. */
 681
 682         j->type = t;
 683         j->state = JOB_WAITING;
 684         j->override = j->override || other->override;
 685
 686         j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
 687
 688         /* Patch us in as new owner of the JobDependency objects */
 689         last = NULL;
 690         LIST_FOREACH(subject, l, other->subject_list) {
 691                 assert(l->subject == other);
 692                 l->subject = j;
 693                 last = l;
 694         }
 695
 696         /* Merge both lists */
 697         if (last) {
 698                 last->subject_next = j->subject_list;
 699                 if (j->subject_list)
 700                         j->subject_list->subject_prev = last;
 701                 j->subject_list = other->subject_list;
 702         }
 703
 704         /* Patch us in as new owner of the JobDependency objects */
 705         last = NULL;
 706         LIST_FOREACH(object, l, other->object_list) {
 707                 assert(l->object == other);
 708                 l->object = j;
 709                 last = l;
 710         }
 711
 712         /* Merge both lists */
 713         if (last) {
 714                 last->object_next = j->object_list;
 715                 if (j->object_list)
 716                         j->object_list->object_prev = last;
 717                 j->object_list = other->object_list;
 718         }
 719
 720         /* Kill the other job */
 721         other->subject_list = NULL;
 722         other->object_list = NULL;
 723         transaction_delete_job(m, other, true);
 724 }
 725 static bool job_is_conflicted_by(Job *j) {
 726         JobDependency *l;
 727
 728         assert(j);
 729
 730         /* Returns true if this job is pulled in by a least one
 731          * ConflictedBy dependency. */
 732
 733         LIST_FOREACH(object, l, j->object_list)
 734                 if (l->conflicts)
 735                         return true;
 736
 737         return false;
 738 }
 739
 740 static int delete_one_unmergeable_job(Manager *m, Job *j) {
 741         Job *k;
 742
 743         assert(j);
 744
 745         /* Tries to delete one item in the linked list
 746          * j->transaction_next->transaction_next->... that conflicts
 747          * whith another one, in an attempt to make an inconsistent
 748          * transaction work. */
 749
 750         /* We rely here on the fact that if a merged with b does not
 751          * merge with c, either a or b merge with c neither */
 752         LIST_FOREACH(transaction, j, j)
 753                 LIST_FOREACH(transaction, k, j->transaction_next) {
 754                         Job *d;
 755
 756                         /* Is this one mergeable? Then skip it */
 757                         if (job_type_is_mergeable(j->type, k->type))
 758                                 continue;
 759
 760                         /* Ok, we found two that conflict, let's see if we can
 761                          * drop one of them */
 762                         if (!j->matters_to_anchor && !k->matters_to_anchor) {
 763
 764                                 /* Both jobs don't matter, so let's
 765                                  * find the one that is smarter to
 766                                  * remove. Let's think positive and
 767                                  * rather remove stops then starts --
 768                                  * except if something is being
 769                                  * stopped because it is conflicted by
 770                                  * another unit in which case we
 771                                  * rather remove the start. */
 772
 773                                 log_debug("Looking at job %s/%s conflicted_by=%s", j->unit->meta.id, job_type_to_string(j->type), yes_no(j->type == JOB_STOP && job_is_conflicted_by(j)));
 774                                 log_debug("Looking at job %s/%s conflicted_by=%s", k->unit->meta.id, job_type_to_string(k->type), yes_no(k->type == JOB_STOP && job_is_conflicted_by(k)));
 775
 776                                 if (j->type == JOB_STOP) {
 777
 778                                         if (job_is_conflicted_by(j))
 779                                                 d = k;
 780                                         else
 781                                                 d = j;
 782
 783                                 } else if (k->type == JOB_STOP) {
 784
 785                                         if (job_is_conflicted_by(k))
 786                                                 d = j;
 787                                         else
 788                                                 d = k;
 789                                 }
 790
 791                         } else if (!j->matters_to_anchor)
 792                                 d = j;
 793                         else if (!k->matters_to_anchor)
 794                                 d = k;
 795                         else
 796                                 return -ENOEXEC;
 797
 798                         /* Ok, we can drop one, so let's do so. */
 799                         log_debug("Fixing conflicting jobs by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type));
 800                         transaction_delete_job(m, d, true);
 801                         return 0;
 802                 }
 803
 804         return -EINVAL;
 805 }
 806
 807 static int transaction_merge_jobs(Manager *m, DBusError *e) {
 808         Job *j;
 809         Iterator i;
 810         int r;
 811
 812         assert(m);
 813
 814         /* First step, check whether any of the jobs for one specific
 815          * task conflict. If so, try to drop one of them. */
 816         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 817                 JobType t;
 818                 Job *k;
 819
 820                 t = j->type;
 821                 LIST_FOREACH(transaction, k, j->transaction_next) {
 822                         if ((r = job_type_merge(&t, k->type)) >= 0)
 823                                 continue;
 824
 825                         /* OK, we could not merge all jobs for this
 826                          * action. Let's see if we can get rid of one
 827                          * of them */
 828
 829                         if ((r = delete_one_unmergeable_job(m, j)) >= 0)
 830                                 /* Ok, we managed to drop one, now
 831                                  * let's ask our callers to call us
 832                                  * again after garbage collecting */
 833                                 return -EAGAIN;
 834
 835                         /* We couldn't merge anything. Failure */
 836                         dbus_set_error(e, BUS_ERROR_TRANSACTION_JOBS_CONFLICTING, "Transaction contains conflicting jobs '%s' and '%s' for %s. Probably contradicting requirement dependencies configured.",
 837                                        job_type_to_string(t), job_type_to_string(k->type), k->unit->meta.id);
 838                         return r;
 839                 }
 840         }
 841
 842         /* Second step, merge the jobs. */
 843         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 844                 JobType t = j->type;
 845                 Job *k;
 846
 847                 /* Merge all transactions */
 848                 LIST_FOREACH(transaction, k, j->transaction_next)
 849                         assert_se(job_type_merge(&t, k->type) == 0);
 850
 851                 /* If an active job is mergeable, merge it too */
 852                 if (j->unit->meta.job)
 853                         job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
 854
 855                 while ((k = j->transaction_next)) {
 856                         if (j->installed) {
 857                                 transaction_merge_and_delete_job(m, k, j, t);
 858                                 j = k;
 859                         } else
 860                                 transaction_merge_and_delete_job(m, j, k, t);
 861                 }
 862
 863                 assert(!j->transaction_next);
 864                 assert(!j->transaction_prev);
 865         }
 866
 867         return 0;
 868 }
 869
 870 static void transaction_drop_redundant(Manager *m) {
 871         bool again;
 872
 873         assert(m);
 874
 875         /* Goes through the transaction and removes all jobs that are
 876          * a noop */
 877
 878         do {
 879                 Job *j;
 880                 Iterator i;
 881
 882                 again = false;
 883
 884                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 885                         bool changes_something = false;
 886                         Job *k;
 887
 888                         LIST_FOREACH(transaction, k, j) {
 889
 890                                 if (!job_is_anchor(k) &&
 891                                     job_type_is_redundant(k->type, unit_active_state(k->unit)))
 892                                         continue;
 893
 894                                 changes_something = true;
 895                                 break;
 896                         }
 897
 898                         if (changes_something)
 899                                 continue;
 900
 901                         log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type));
 902                         transaction_delete_job(m, j, false);
 903                         again = true;
 904                         break;
 905                 }
 906
 907         } while (again);
 908 }
 909
 910 static bool unit_matters_to_anchor(Unit *u, Job *j) {
 911         assert(u);
 912         assert(!j->transaction_prev);
 913
 914         /* Checks whether at least one of the jobs for this unit
 915          * matters to the anchor. */
 916
 917         LIST_FOREACH(transaction, j, j)
 918                 if (j->matters_to_anchor)
 919                         return true;
 920
 921         return false;
 922 }
 923
 924 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation, DBusError *e) {
 925         Iterator i;
 926         Unit *u;
 927         int r;
 928
 929         assert(m);
 930         assert(j);
 931         assert(!j->transaction_prev);
 932
 933         /* Does a recursive sweep through the ordering graph, looking
 934          * for a cycle. If we find cycle we try to break it. */
 935
 936         /* Have we seen this before? */
 937         if (j->generation == generation) {
 938                 Job *k, *delete;
 939
 940                 /* If the marker is NULL we have been here already and
 941                  * decided the job was loop-free from here. Hence
 942                  * shortcut things and return right-away. */
 943                 if (!j->marker)
 944                         return 0;
 945
 946                 /* So, the marker is not NULL and we already have been
 947                  * here. We have a cycle. Let's try to break it. We go
 948                  * backwards in our path and try to find a suitable
 949                  * job to remove. We use the marker to find our way
 950                  * back, since smart how we are we stored our way back
 951                  * in there. */
 952                 log_warning("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type));
 953
 954                 delete = NULL;
 955                 for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) {
 956
 957                         log_info("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 958
 959                         if (!delete &&
 960                             !k->installed &&
 961                             !unit_matters_to_anchor(k->unit, k)) {
 962                                 /* Ok, we can drop this one, so let's
 963                                  * do so. */
 964                                 delete = k;
 965                         }
 966
 967                         /* Check if this in fact was the beginning of
 968                          * the cycle */
 969                         if (k == j)
 970                                 break;
 971                 }
 972
 973
 974                 if (delete) {
 975                         log_warning("Breaking ordering cycle by deleting job %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 976                         transaction_delete_unit(m, delete->unit);
 977                         return -EAGAIN;
 978                 }
 979
 980                 log_error("Unable to break cycle");
 981
 982                 dbus_set_error(e, BUS_ERROR_TRANSACTION_ORDER_IS_CYCLIC, "Transaction order is cyclic. See logs for details.");
 983                 return -ENOEXEC;
 984         }
 985
 986         /* Make the marker point to where we come from, so that we can
 987          * find our way backwards if we want to break a cycle. We use
 988          * a special marker for the beginning: we point to
 989          * ourselves. */
 990         j->marker = from ? from : j;
 991         j->generation = generation;
 992
 993         /* We assume that the the dependencies are bidirectional, and
 994          * hence can ignore UNIT_AFTER */
 995         SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
 996                 Job *o;
 997
 998                 /* Is there a job for this unit? */
 999                 if (!(o = hashmap_get(m->transaction_jobs, u)))
1000
1001                         /* Ok, there is no job for this in the
1002                          * transaction, but maybe there is already one
1003                          * running? */
1004                         if (!(o = u->meta.job))
1005                                 continue;
1006
1007                 if ((r = transaction_verify_order_one(m, o, j, generation, e)) < 0)
1008                         return r;
1009         }
1010
1011         /* Ok, let's backtrack, and remember that this entry is not on
1012          * our path anymore. */
1013         j->marker = NULL;
1014
1015         return 0;
1016 }
1017
1018 static int transaction_verify_order(Manager *m, unsigned *generation, DBusError *e) {
1019         Job *j;
1020         int r;
1021         Iterator i;
1022         unsigned g;
1023
1024         assert(m);
1025         assert(generation);
1026
1027         /* Check if the ordering graph is cyclic. If it is, try to fix
1028          * that up by dropping one of the jobs. */
1029
1030         g = (*generation)++;
1031
1032         HASHMAP_FOREACH(j, m->transaction_jobs, i)
1033                 if ((r = transaction_verify_order_one(m, j, NULL, g, e)) < 0)
1034                         return r;
1035
1036         return 0;
1037 }
1038
1039 static void transaction_collect_garbage(Manager *m) {
1040         bool again;
1041
1042         assert(m);
1043
1044         /* Drop jobs that are not required by any other job */
1045
1046         do {
1047                 Iterator i;
1048                 Job *j;
1049
1050                 again = false;
1051
1052                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1053                         if (j->object_list)
1054                                 continue;
1055
1056                         log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type));
1057                         transaction_delete_job(m, j, true);
1058                         again = true;
1059                         break;
1060                 }
1061
1062         } while (again);
1063 }
1064
1065 static int transaction_is_destructive(Manager *m, DBusError *e) {
1066         Iterator i;
1067         Job *j;
1068
1069         assert(m);
1070
1071         /* Checks whether applying this transaction means that
1072          * existing jobs would be replaced */
1073
1074         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1075
1076                 /* Assume merged */
1077                 assert(!j->transaction_prev);
1078                 assert(!j->transaction_next);
1079
1080                 if (j->unit->meta.job &&
1081                     j->unit->meta.job != j &&
1082                     !job_type_is_superset(j->type, j->unit->meta.job->type)) {
1083
1084                         dbus_set_error(e, BUS_ERROR_TRANSACTION_IS_DESTRUCTIVE, "Transaction is destructive.");
1085                         return -EEXIST;
1086                 }
1087         }
1088
1089         return 0;
1090 }
1091
1092 static void transaction_minimize_impact(Manager *m) {
1093         bool again;
1094         assert(m);
1095
1096         /* Drops all unnecessary jobs that reverse already active jobs
1097          * or that stop a running service. */
1098
1099         do {
1100                 Job *j;
1101                 Iterator i;
1102
1103                 again = false;
1104
1105                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1106                         LIST_FOREACH(transaction, j, j) {
1107                                 bool stops_running_service, changes_existing_job;
1108
1109                                 /* If it matters, we shouldn't drop it */
1110                                 if (j->matters_to_anchor)
1111                                         continue;
1112
1113                                 /* Would this stop a running service?
1114                                  * Would this change an existing job?
1115                                  * If so, let's drop this entry */
1116
1117                                 stops_running_service =
1118                                         j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
1119
1120                                 changes_existing_job =
1121                                         j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->type);
1122
1123                                 if (!stops_running_service && !changes_existing_job)
1124                                         continue;
1125
1126                                 if (stops_running_service)
1127                                         log_info("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type));
1128
1129                                 if (changes_existing_job)
1130                                         log_info("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type));
1131
1132                                 /* Ok, let's get rid of this */
1133                                 log_info("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type));
1134
1135                                 transaction_delete_job(m, j, true);
1136                                 again = true;
1137                                 break;
1138                         }
1139
1140                         if (again)
1141                                 break;
1142                 }
1143
1144         } while (again);
1145 }
1146
1147 static int transaction_apply(Manager *m) {
1148         Iterator i;
1149         Job *j;
1150         int r;
1151
1152         /* Moves the transaction jobs to the set of active jobs */
1153
1154         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1155                 /* Assume merged */
1156                 assert(!j->transaction_prev);
1157                 assert(!j->transaction_next);
1158
1159                 if (j->installed)
1160                         continue;
1161
1162                 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
1163                         goto rollback;
1164         }
1165
1166         while ((j = hashmap_steal_first(m->transaction_jobs))) {
1167                 if (j->installed)
1168                         continue;
1169
1170                 if (j->unit->meta.job)
1171                         job_free(j->unit->meta.job);
1172
1173                 j->unit->meta.job = j;
1174                 j->installed = true;
1175
1176                 /* We're fully installed. Now let's free data we don't
1177                  * need anymore. */
1178
1179                 assert(!j->transaction_next);
1180                 assert(!j->transaction_prev);
1181
1182                 job_add_to_run_queue(j);
1183                 job_add_to_dbus_queue(j);
1184                 job_start_timer(j);
1185         }
1186
1187         /* As last step, kill all remaining job dependencies. */
1188         transaction_clean_dependencies(m);
1189
1190         return 0;
1191
1192 rollback:
1193
1194         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1195                 if (j->installed)
1196                         continue;
1197
1198                 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1199         }
1200
1201         return r;
1202 }
1203
1204 static int transaction_activate(Manager *m, JobMode mode, DBusError *e) {
1205         int r;
1206         unsigned generation = 1;
1207
1208         assert(m);
1209
1210         /* This applies the changes recorded in transaction_jobs to
1211          * the actual list of jobs, if possible. */
1212
1213         /* First step: figure out which jobs matter */
1214         transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1215
1216         /* Second step: Try not to stop any running services if
1217          * we don't have to. Don't try to reverse running
1218          * jobs if we don't have to. */
1219         transaction_minimize_impact(m);
1220
1221         /* Third step: Drop redundant jobs */
1222         transaction_drop_redundant(m);
1223
1224         for (;;) {
1225                 /* Fourth step: Let's remove unneeded jobs that might
1226                  * be lurking. */
1227                 transaction_collect_garbage(m);
1228
1229                 /* Fifth step: verify order makes sense and correct
1230                  * cycles if necessary and possible */
1231                 if ((r = transaction_verify_order(m, &generation, e)) >= 0)
1232                         break;
1233
1234                 if (r != -EAGAIN) {
1235                         log_warning("Requested transaction contains an unfixable cyclic ordering dependency: %s", bus_error(e, r));
1236                         goto rollback;
1237                 }
1238
1239                 /* Let's see if the resulting transaction ordering
1240                  * graph is still cyclic... */
1241         }
1242
1243         for (;;) {
1244                 /* Sixth step: let's drop unmergeable entries if
1245                  * necessary and possible, merge entries we can
1246                  * merge */
1247                 if ((r = transaction_merge_jobs(m, e)) >= 0)
1248                         break;
1249
1250                 if (r != -EAGAIN) {
1251                         log_warning("Requested transaction contains unmergable jobs: %s", bus_error(e, r));
1252                         goto rollback;
1253                 }
1254
1255                 /* Seventh step: an entry got dropped, let's garbage
1256                  * collect its dependencies. */
1257                 transaction_collect_garbage(m);
1258
1259                 /* Let's see if the resulting transaction still has
1260                  * unmergeable entries ... */
1261         }
1262
1263         /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1264         transaction_drop_redundant(m);
1265
1266         /* Ninth step: check whether we can actually apply this */
1267         if (mode == JOB_FAIL)
1268                 if ((r = transaction_is_destructive(m, e)) < 0) {
1269                         log_notice("Requested transaction contradicts existing jobs: %s", bus_error(e, r));
1270                         goto rollback;
1271                 }
1272
1273         /* Tenth step: apply changes */
1274         if ((r = transaction_apply(m)) < 0) {
1275                 log_warning("Failed to apply transaction: %s", strerror(-r));
1276                 goto rollback;
1277         }
1278
1279         assert(hashmap_isempty(m->transaction_jobs));
1280         assert(!m->transaction_anchor);
1281
1282         return 0;
1283
1284 rollback:
1285         transaction_abort(m);
1286         return r;
1287 }
1288
1289 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1290         Job *j, *f;
1291         int r;
1292
1293         assert(m);
1294         assert(unit);
1295
1296         /* Looks for an axisting prospective job and returns that. If
1297          * it doesn't exist it is created and added to the prospective
1298          * jobs list. */
1299
1300         f = hashmap_get(m->transaction_jobs, unit);
1301
1302         LIST_FOREACH(transaction, j, f) {
1303                 assert(j->unit == unit);
1304
1305                 if (j->type == type) {
1306                         if (is_new)
1307                                 *is_new = false;
1308                         return j;
1309                 }
1310         }
1311
1312         if (unit->meta.job && unit->meta.job->type == type)
1313                 j = unit->meta.job;
1314         else if (!(j = job_new(m, type, unit)))
1315                 return NULL;
1316
1317         j->generation = 0;
1318         j->marker = NULL;
1319         j->matters_to_anchor = false;
1320         j->override = override;
1321
1322         LIST_PREPEND(Job, transaction, f, j);
1323
1324         if ((r = hashmap_replace(m->transaction_jobs, unit, f)) < 0) {
1325                 job_free(j);
1326                 return NULL;
1327         }
1328
1329         if (is_new)
1330                 *is_new = true;
1331
1332         log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1333
1334         return j;
1335 }
1336
1337 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1338         assert(m);
1339         assert(j);
1340
1341         if (j->transaction_prev)
1342                 j->transaction_prev->transaction_next = j->transaction_next;
1343         else if (j->transaction_next)
1344                 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1345         else
1346                 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1347
1348         if (j->transaction_next)
1349                 j->transaction_next->transaction_prev = j->transaction_prev;
1350
1351         j->transaction_prev = j->transaction_next = NULL;
1352
1353         while (j->subject_list)
1354                 job_dependency_free(j->subject_list);
1355
1356         while (j->object_list) {
1357                 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1358
1359                 job_dependency_free(j->object_list);
1360
1361                 if (other && delete_dependencies) {
1362                         log_debug("Deleting job %s/%s as dependency of job %s/%s",
1363                                   other->unit->meta.id, job_type_to_string(other->type),
1364                                   j->unit->meta.id, job_type_to_string(j->type));
1365                         transaction_delete_job(m, other, delete_dependencies);
1366                 }
1367         }
1368 }
1369
1370 static int transaction_add_job_and_dependencies(
1371                 Manager *m,
1372                 JobType type,
1373                 Unit *unit,
1374                 Job *by,
1375                 bool matters,
1376                 bool override,
1377                 bool conflicts,
1378                 DBusError *e,
1379                 Job **_ret) {
1380         Job *ret;
1381         Iterator i;
1382         Unit *dep;
1383         int r;
1384         bool is_new;
1385
1386         assert(m);
1387         assert(type < _JOB_TYPE_MAX);
1388         assert(unit);
1389
1390         if (type != JOB_STOP &&
1391             unit->meta.load_state != UNIT_LOADED) {
1392                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED, "Unit %s failed to load. See logs for details.", unit->meta.id);
1393                 return -EINVAL;
1394         }
1395
1396         if (!unit_job_is_applicable(unit, type)) {
1397                 dbus_set_error(e, BUS_ERROR_JOB_TYPE_NOT_APPLICABLE, "Job type %s is not applicable for unit %s.", job_type_to_string(type), unit->meta.id);
1398                 return -EBADR;
1399         }
1400
1401         /* First add the job. */
1402         if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1403                 return -ENOMEM;
1404
1405         /* Then, add a link to the job. */
1406         if (!job_dependency_new(by, ret, matters, conflicts))
1407                 return -ENOMEM;
1408
1409         if (is_new) {
1410                 /* Finally, recursively add in all dependencies. */
1411                 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1412                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1413                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1414                                         goto fail;
1415
1416                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1417                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, false, e, NULL)) < 0 && r != -EBADR) {
1418                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1419                                         dbus_error_free(e);
1420                                 }
1421
1422                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1423                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, false, e, NULL)) < 0) {
1424                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1425                                         dbus_error_free(e);
1426                                 }
1427
1428                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1429                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1430                                         goto fail;
1431
1432                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1433                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, false, e, NULL)) < 0 && r != -EBADR) {
1434                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1435                                         dbus_error_free(e);
1436                                 }
1437
1438                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1439                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, true, e, NULL)) < 0 && r != -EBADR)
1440                                         goto fail;
1441
1442                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTED_BY], i)
1443                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1444                                         goto fail;
1445
1446                 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1447
1448                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1449                                 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1450                                         goto fail;
1451                 }
1452
1453                 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1454         }
1455
1456         if (_ret)
1457                 *_ret = ret;
1458
1459         return 0;
1460
1461 fail:
1462         return r;
1463 }
1464
1465 static int transaction_add_isolate_jobs(Manager *m) {
1466         Iterator i;
1467         Unit *u;
1468         char *k;
1469         int r;
1470
1471         assert(m);
1472
1473         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
1474
1475                 /* ignore aliases */
1476                 if (u->meta.id != k)
1477                         continue;
1478
1479                 if (UNIT_VTABLE(u)->no_isolate)
1480                         continue;
1481
1482                 /* No need to stop inactive jobs */
1483                 if (UNIT_IS_INACTIVE_OR_MAINTENANCE(unit_active_state(u)))
1484                         continue;
1485
1486                 /* Is there already something listed for this? */
1487                 if (hashmap_get(m->transaction_jobs, u))
1488                         continue;
1489
1490                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, u, NULL, true, false, false, NULL, NULL)) < 0)
1491                         log_warning("Cannot add isolate job for unit %s, ignoring: %s", u->meta.id, strerror(-r));
1492         }
1493
1494         return 0;
1495 }
1496
1497 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, DBusError *e, Job **_ret) {
1498         int r;
1499         Job *ret;
1500
1501         assert(m);
1502         assert(type < _JOB_TYPE_MAX);
1503         assert(unit);
1504         assert(mode < _JOB_MODE_MAX);
1505
1506         if (mode == JOB_ISOLATE && type != JOB_START) {
1507                 dbus_set_error(e, BUS_ERROR_INVALID_JOB_MODE, "Isolate is only valid for start.");
1508                 return -EINVAL;
1509         }
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, false, e, &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, e)) < 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, DBusError *e, 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, NULL, &unit)) < 0)
1545                 return r;
1546
1547         return manager_add_job(m, type, unit, mode, override, e, _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, DBusError *e, 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                 dbus_set_error(e, BUS_ERROR_INVALID_PATH, "Path %s is not absolute.", path);
1601                 return -EINVAL;
1602         }
1603
1604         if (!name)
1605                 name = file_name_from_path(path);
1606
1607         if (!unit_name_is_valid(name)) {
1608                 dbus_set_error(e, BUS_ERROR_INVALID_NAME, "Unit name %s is not valid.", name);
1609                 return -EINVAL;
1610         }
1611
1612         if ((ret = manager_get_unit(m, name))) {
1613                 *_ret = ret;
1614                 return 1;
1615         }
1616
1617         if (!(ret = unit_new(m)))
1618                 return -ENOMEM;
1619
1620         if (path)
1621                 if (!(ret->meta.fragment_path = strdup(path))) {
1622                         unit_free(ret);
1623                         return -ENOMEM;
1624                 }
1625
1626         if ((r = unit_add_name(ret, name)) < 0) {
1627                 unit_free(ret);
1628                 return r;
1629         }
1630
1631         unit_add_to_load_queue(ret);
1632         unit_add_to_dbus_queue(ret);
1633         unit_add_to_gc_queue(ret);
1634
1635         if (_ret)
1636                 *_ret = ret;
1637
1638         return 0;
1639 }
1640
1641 int manager_load_unit(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1642         int r;
1643
1644         assert(m);
1645
1646         /* This will load the service information files, but not actually
1647          * start any services or anything. */
1648
1649         if ((r = manager_load_unit_prepare(m, name, path, e, _ret)) != 0)
1650                 return r;
1651
1652         manager_dispatch_load_queue(m);
1653
1654         if (_ret)
1655                 *_ret = unit_follow_merge(*_ret);
1656
1657         return 0;
1658 }
1659
1660 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1661         Iterator i;
1662         Job *j;
1663
1664         assert(s);
1665         assert(f);
1666
1667         HASHMAP_FOREACH(j, s->jobs, i)
1668                 job_dump(j, f, prefix);
1669 }
1670
1671 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1672         Iterator i;
1673         Unit *u;
1674         const char *t;
1675
1676         assert(s);
1677         assert(f);
1678
1679         HASHMAP_FOREACH_KEY(u, t, s->units, i)
1680                 if (u->meta.id == t)
1681                         unit_dump(u, f, prefix);
1682 }
1683
1684 void manager_clear_jobs(Manager *m) {
1685         Job *j;
1686
1687         assert(m);
1688
1689         transaction_abort(m);
1690
1691         while ((j = hashmap_first(m->jobs)))
1692                 job_free(j);
1693 }
1694
1695 unsigned manager_dispatch_run_queue(Manager *m) {
1696         Job *j;
1697         unsigned n = 0;
1698
1699         if (m->dispatching_run_queue)
1700                 return 0;
1701
1702         m->dispatching_run_queue = true;
1703
1704         while ((j = m->run_queue)) {
1705                 assert(j->installed);
1706                 assert(j->in_run_queue);
1707
1708                 job_run_and_invalidate(j);
1709                 n++;
1710         }
1711
1712         m->dispatching_run_queue = false;
1713         return n;
1714 }
1715
1716 unsigned manager_dispatch_dbus_queue(Manager *m) {
1717         Job *j;
1718         Meta *meta;
1719         unsigned n = 0;
1720
1721         assert(m);
1722
1723         if (m->dispatching_dbus_queue)
1724                 return 0;
1725
1726         m->dispatching_dbus_queue = true;
1727
1728         while ((meta = m->dbus_unit_queue)) {
1729                 assert(meta->in_dbus_queue);
1730
1731                 bus_unit_send_change_signal((Unit*) meta);
1732                 n++;
1733         }
1734
1735         while ((j = m->dbus_job_queue)) {
1736                 assert(j->in_dbus_queue);
1737
1738                 bus_job_send_change_signal(j);
1739                 n++;
1740         }
1741
1742         m->dispatching_dbus_queue = false;
1743         return n;
1744 }
1745
1746 static int manager_process_notify_fd(Manager *m) {
1747         ssize_t n;
1748
1749         assert(m);
1750
1751         for (;;) {
1752                 char buf[4096];
1753                 struct msghdr msghdr;
1754                 struct iovec iovec;
1755                 struct ucred *ucred;
1756                 union {
1757                         struct cmsghdr cmsghdr;
1758                         uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
1759                 } control;
1760                 Unit *u;
1761                 char **tags;
1762
1763                 zero(iovec);
1764                 iovec.iov_base = buf;
1765                 iovec.iov_len = sizeof(buf)-1;
1766
1767                 zero(control);
1768                 zero(msghdr);
1769                 msghdr.msg_iov = &iovec;
1770                 msghdr.msg_iovlen = 1;
1771                 msghdr.msg_control = &control;
1772                 msghdr.msg_controllen = sizeof(control);
1773
1774                 if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) <= 0) {
1775                         if (n >= 0)
1776                                 return -EIO;
1777
1778                         if (errno == EAGAIN)
1779                                 break;
1780
1781                         return -errno;
1782                 }
1783
1784                 if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
1785                     control.cmsghdr.cmsg_level != SOL_SOCKET ||
1786                     control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
1787                     control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
1788                         log_warning("Received notify message without credentials. Ignoring.");
1789                         continue;
1790                 }
1791
1792                 ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
1793
1794                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(ucred->pid))))
1795                         if (!(u = cgroup_unit_by_pid(m, ucred->pid))) {
1796                                 log_warning("Cannot find unit for notify message of PID %lu.", (unsigned long) ucred->pid);
1797                                 continue;
1798                         }
1799
1800                 assert((size_t) n < sizeof(buf));
1801                 buf[n] = 0;
1802                 if (!(tags = strv_split(buf, "\n\r")))
1803                         return -ENOMEM;
1804
1805                 log_debug("Got notification message for unit %s", u->meta.id);
1806
1807                 if (UNIT_VTABLE(u)->notify_message)
1808                         UNIT_VTABLE(u)->notify_message(u, ucred->pid, tags);
1809
1810                 strv_free(tags);
1811         }
1812
1813         return 0;
1814 }
1815
1816 static int manager_dispatch_sigchld(Manager *m) {
1817         assert(m);
1818
1819         for (;;) {
1820                 siginfo_t si;
1821                 Unit *u;
1822                 int r;
1823
1824                 zero(si);
1825
1826                 /* First we call waitd() for a PID and do not reap the
1827                  * zombie. That way we can still access /proc/$PID for
1828                  * it while it is a zombie. */
1829                 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1830
1831                         if (errno == ECHILD)
1832                                 break;
1833
1834                         if (errno == EINTR)
1835                                 continue;
1836
1837                         return -errno;
1838                 }
1839
1840                 if (si.si_pid <= 0)
1841                         break;
1842
1843                 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1844                         char *name = NULL;
1845
1846                         get_process_name(si.si_pid, &name);
1847                         log_debug("Got SIGCHLD for process %lu (%s)", (unsigned long) si.si_pid, strna(name));
1848                         free(name);
1849                 }
1850
1851                 /* Let's flush any message the dying child might still
1852                  * have queued for us. This ensures that the process
1853                  * still exists in /proc so that we can figure out
1854                  * which cgroup and hence unit it belongs to. */
1855                 if ((r = manager_process_notify_fd(m)) < 0)
1856                         return r;
1857
1858                 /* And now figure out the unit this belongs to */
1859                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(si.si_pid))))
1860                         u = cgroup_unit_by_pid(m, si.si_pid);
1861
1862                 /* And now, we actually reap the zombie. */
1863                 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1864                         if (errno == EINTR)
1865                                 continue;
1866
1867                         return -errno;
1868                 }
1869
1870                 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1871                         continue;
1872
1873                 log_debug("Child %lu died (code=%s, status=%i/%s)",
1874                           (long unsigned) si.si_pid,
1875                           sigchld_code_to_string(si.si_code),
1876                           si.si_status,
1877                           strna(si.si_code == CLD_EXITED ? exit_status_to_string(si.si_status) : signal_to_string(si.si_status)));
1878
1879                 if (!u)
1880                         continue;
1881
1882                 log_debug("Child %lu belongs to %s", (long unsigned) si.si_pid, u->meta.id);
1883
1884                 hashmap_remove(m->watch_pids, LONG_TO_PTR(si.si_pid));
1885                 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1886         }
1887
1888         return 0;
1889 }
1890
1891 static int manager_start_target(Manager *m, const char *name, JobMode mode) {
1892         int r;
1893         DBusError error;
1894
1895         dbus_error_init(&error);
1896
1897         log_info("Activating special unit %s", name);
1898
1899         if ((r = manager_add_job_by_name(m, JOB_START, name, mode, true, &error, NULL)) < 0)
1900                 log_error("Failed to enqueue %s job: %s", name, bus_error(&error, r));
1901
1902         dbus_error_free(&error);
1903
1904         return r;
1905 }
1906
1907 static int manager_process_signal_fd(Manager *m) {
1908         ssize_t n;
1909         struct signalfd_siginfo sfsi;
1910         bool sigchld = false;
1911
1912         assert(m);
1913
1914         for (;;) {
1915                 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1916
1917                         if (n >= 0)
1918                                 return -EIO;
1919
1920                         if (errno == EAGAIN)
1921                                 break;
1922
1923                         return -errno;
1924                 }
1925
1926                 log_debug("Received SIG%s", strna(signal_to_string(sfsi.ssi_signo)));
1927
1928                 switch (sfsi.ssi_signo) {
1929
1930                 case SIGCHLD:
1931                         sigchld = true;
1932                         break;
1933
1934                 case SIGTERM:
1935                         if (m->running_as == MANAGER_SYSTEM) {
1936                                 /* This is for compatibility with the
1937                                  * original sysvinit */
1938                                 m->exit_code = MANAGER_REEXECUTE;
1939                                 break;
1940                         }
1941
1942                         /* Fall through */
1943
1944                 case SIGINT:
1945                         if (m->running_as == MANAGER_SYSTEM) {
1946                                 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET, JOB_REPLACE);
1947                                 break;
1948                         }
1949
1950                         /* Run the exit target if there is one, if not, just exit. */
1951                         if (manager_start_target(m, SPECIAL_EXIT_SERVICE, JOB_REPLACE) < 0) {
1952                                 m->exit_code = MANAGER_EXIT;
1953                                 return 0;
1954                         }
1955
1956                         break;
1957
1958                 case SIGWINCH:
1959                         if (m->running_as == MANAGER_SYSTEM)
1960                                 manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE);
1961
1962                         /* This is a nop on non-init */
1963                         break;
1964
1965                 case SIGPWR:
1966                         if (m->running_as == MANAGER_SYSTEM)
1967                                 manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE);
1968
1969                         /* This is a nop on non-init */
1970                         break;
1971
1972                 case SIGUSR1: {
1973                         Unit *u;
1974
1975                         u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
1976
1977                         if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
1978                                 log_info("Trying to reconnect to bus...");
1979                                 bus_init(m);
1980                         }
1981
1982                         if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
1983                                 log_info("Loading D-Bus service...");
1984                                 manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE);
1985                         }
1986
1987                         break;
1988                 }
1989
1990                 case SIGUSR2: {
1991                         FILE *f;
1992                         char *dump = NULL;
1993                         size_t size;
1994
1995                         if (!(f = open_memstream(&dump, &size))) {
1996                                 log_warning("Failed to allocate memory stream.");
1997                                 break;
1998                         }
1999
2000                         manager_dump_units(m, f, "\t");
2001                         manager_dump_jobs(m, f, "\t");
2002
2003                         if (ferror(f)) {
2004                                 fclose(f);
2005                                 free(dump);
2006                                 log_warning("Failed to write status stream");
2007                                 break;
2008                         }
2009
2010                         fclose(f);
2011                         log_dump(LOG_INFO, dump);
2012                         free(dump);
2013
2014                         break;
2015                 }
2016
2017                 case SIGHUP:
2018                         m->exit_code = MANAGER_RELOAD;
2019                         break;
2020
2021                 default: {
2022                         static const char * const table[] = {
2023                                 [0] = SPECIAL_DEFAULT_TARGET,
2024                                 [1] = SPECIAL_RESCUE_TARGET,
2025                                 [2] = SPECIAL_EMERGENCY_TARGET,
2026                                 [3] = SPECIAL_HALT_TARGET,
2027                                 [4] = SPECIAL_POWEROFF_TARGET,
2028                                 [5] = SPECIAL_REBOOT_TARGET
2029                         };
2030
2031                         if ((int) sfsi.ssi_signo >= SIGRTMIN+0 &&
2032                             (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(table)) {
2033                                 manager_start_target(m, table[sfsi.ssi_signo - SIGRTMIN],
2034                                                      (sfsi.ssi_signo == 1 || sfsi.ssi_signo == 2) ? JOB_ISOLATE : JOB_REPLACE);
2035                                 break;
2036                         }
2037
2038                         log_warning("Got unhandled signal <%s>.", strna(signal_to_string(sfsi.ssi_signo)));
2039                 }
2040                 }
2041         }
2042
2043         if (sigchld)
2044                 return manager_dispatch_sigchld(m);
2045
2046         return 0;
2047 }
2048
2049 static int process_event(Manager *m, struct epoll_event *ev) {
2050         int r;
2051         Watch *w;
2052
2053         assert(m);
2054         assert(ev);
2055
2056         assert(w = ev->data.ptr);
2057
2058         switch (w->type) {
2059
2060         case WATCH_SIGNAL:
2061
2062                 /* An incoming signal? */
2063                 if (ev->events != EPOLLIN)
2064                         return -EINVAL;
2065
2066                 if ((r = manager_process_signal_fd(m)) < 0)
2067                         return r;
2068
2069                 break;
2070
2071         case WATCH_NOTIFY:
2072
2073                 /* An incoming daemon notification event? */
2074                 if (ev->events != EPOLLIN)
2075                         return -EINVAL;
2076
2077                 if ((r = manager_process_notify_fd(m)) < 0)
2078                         return r;
2079
2080                 break;
2081
2082         case WATCH_FD:
2083
2084                 /* Some fd event, to be dispatched to the units */
2085                 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
2086                 break;
2087
2088         case WATCH_UNIT_TIMER:
2089         case WATCH_JOB_TIMER: {
2090                 uint64_t v;
2091                 ssize_t k;
2092
2093                 /* Some timer event, to be dispatched to the units */
2094                 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
2095
2096                         if (k < 0 && (errno == EINTR || errno == EAGAIN))
2097                                 break;
2098
2099                         return k < 0 ? -errno : -EIO;
2100                 }
2101
2102                 if (w->type == WATCH_UNIT_TIMER)
2103                         UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
2104                 else
2105                         job_timer_event(w->data.job, v, w);
2106                 break;
2107         }
2108
2109         case WATCH_MOUNT:
2110                 /* Some mount table change, intended for the mount subsystem */
2111                 mount_fd_event(m, ev->events);
2112                 break;
2113
2114         case WATCH_UDEV:
2115                 /* Some notification from udev, intended for the device subsystem */
2116                 device_fd_event(m, ev->events);
2117                 break;
2118
2119         case WATCH_DBUS_WATCH:
2120                 bus_watch_event(m, w, ev->events);
2121                 break;
2122
2123         case WATCH_DBUS_TIMEOUT:
2124                 bus_timeout_event(m, w, ev->events);
2125                 break;
2126
2127         default:
2128                 assert_not_reached("Unknown epoll event type.");
2129         }
2130
2131         return 0;
2132 }
2133
2134 int manager_loop(Manager *m) {
2135         int r;
2136
2137         RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
2138
2139         assert(m);
2140         m->exit_code = MANAGER_RUNNING;
2141
2142         /* Release the path cache */
2143         set_free_free(m->unit_path_cache);
2144         m->unit_path_cache = NULL;
2145
2146         /* There might still be some zombies hanging around from
2147          * before we were exec()'ed. Leat's reap them */
2148         if ((r = manager_dispatch_sigchld(m)) < 0)
2149                 return r;
2150
2151         while (m->exit_code == MANAGER_RUNNING) {
2152                 struct epoll_event event;
2153                 int n;
2154
2155                 if (!ratelimit_test(&rl)) {
2156                         /* Yay, something is going seriously wrong, pause a little */
2157                         log_warning("Looping too fast. Throttling execution a little.");
2158                         sleep(1);
2159                 }
2160
2161                 if (manager_dispatch_load_queue(m) > 0)
2162                         continue;
2163
2164                 if (manager_dispatch_run_queue(m) > 0)
2165                         continue;
2166
2167                 if (bus_dispatch(m) > 0)
2168                         continue;
2169
2170                 if (manager_dispatch_cleanup_queue(m) > 0)
2171                         continue;
2172
2173                 if (manager_dispatch_gc_queue(m) > 0)
2174                         continue;
2175
2176                 if (manager_dispatch_dbus_queue(m) > 0)
2177                         continue;
2178
2179                 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
2180
2181                         if (errno == EINTR)
2182                                 continue;
2183
2184                         return -errno;
2185                 }
2186
2187                 assert(n == 1);
2188
2189                 if ((r = process_event(m, &event)) < 0)
2190                         return r;
2191         }
2192
2193         return m->exit_code;
2194 }
2195
2196 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
2197         char *n;
2198         Unit *u;
2199
2200         assert(m);
2201         assert(s);
2202         assert(_u);
2203
2204         if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
2205                 return -EINVAL;
2206
2207         if (!(n = bus_path_unescape(s+31)))
2208                 return -ENOMEM;
2209
2210         u = manager_get_unit(m, n);
2211         free(n);
2212
2213         if (!u)
2214                 return -ENOENT;
2215
2216         *_u = u;
2217
2218         return 0;
2219 }
2220
2221 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
2222         Job *j;
2223         unsigned id;
2224         int r;
2225
2226         assert(m);
2227         assert(s);
2228         assert(_j);
2229
2230         if (!startswith(s, "/org/freedesktop/systemd1/job/"))
2231                 return -EINVAL;
2232
2233         if ((r = safe_atou(s + 30, &id)) < 0)
2234                 return r;
2235
2236         if (!(j = manager_get_job(m, id)))
2237                 return -ENOENT;
2238
2239         *_j = j;
2240
2241         return 0;
2242 }
2243
2244 void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success) {
2245
2246 #ifdef HAVE_AUDIT
2247         char *p;
2248
2249         if (m->audit_fd < 0)
2250                 return;
2251
2252         if (!(p = unit_name_to_prefix_and_instance(u->meta.id))) {
2253                 log_error("Failed to allocate unit name for audit message: %s", strerror(ENOMEM));
2254                 return;
2255         }
2256
2257         if (audit_log_user_comm_message(m->audit_fd, type, "", p, NULL, NULL, NULL, success) < 0)
2258                 log_error("Failed to send audit message: %m");
2259
2260         free(p);
2261 #endif
2262
2263 }
2264
2265 void manager_dispatch_bus_name_owner_changed(
2266                 Manager *m,
2267                 const char *name,
2268                 const char* old_owner,
2269                 const char *new_owner) {
2270
2271         Unit *u;
2272
2273         assert(m);
2274         assert(name);
2275
2276         if (!(u = hashmap_get(m->watch_bus, name)))
2277                 return;
2278
2279         UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
2280 }
2281
2282 void manager_dispatch_bus_query_pid_done(
2283                 Manager *m,
2284                 const char *name,
2285                 pid_t pid) {
2286
2287         Unit *u;
2288
2289         assert(m);
2290         assert(name);
2291         assert(pid >= 1);
2292
2293         if (!(u = hashmap_get(m->watch_bus, name)))
2294                 return;
2295
2296         UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
2297 }
2298
2299 int manager_open_serialization(Manager *m, FILE **_f) {
2300         char *path;
2301         mode_t saved_umask;
2302         int fd;
2303         FILE *f;
2304
2305         assert(_f);
2306
2307         if (m->running_as == MANAGER_SYSTEM) {
2308                 mkdir_p("/dev/.systemd", 0755);
2309
2310                 if (asprintf(&path, "/dev/.systemd/dump-%lu-XXXXXX", (unsigned long) getpid()) < 0)
2311                         return -ENOMEM;
2312         } else {
2313                 if (asprintf(&path, "/tmp/systemd-dump-%lu-XXXXXX", (unsigned long) getpid()) < 0)
2314                         return -ENOMEM;
2315         }
2316
2317         saved_umask = umask(0077);
2318         fd = mkostemp(path, O_RDWR|O_CLOEXEC);
2319         umask(saved_umask);
2320
2321         if (fd < 0) {
2322                 free(path);
2323                 return -errno;
2324         }
2325
2326         unlink(path);
2327
2328         log_debug("Serializing state to %s", path);
2329         free(path);
2330
2331         if (!(f = fdopen(fd, "w+")) < 0)
2332                 return -errno;
2333
2334         *_f = f;
2335
2336         return 0;
2337 }
2338
2339 int manager_serialize(Manager *m, FILE *f, FDSet *fds) {
2340         Iterator i;
2341         Unit *u;
2342         const char *t;
2343         int r;
2344
2345         assert(m);
2346         assert(f);
2347         assert(fds);
2348
2349         HASHMAP_FOREACH_KEY(u, t, m->units, i) {
2350                 if (u->meta.id != t)
2351                         continue;
2352
2353                 if (!unit_can_serialize(u))
2354                         continue;
2355
2356                 /* Start marker */
2357                 fputs(u->meta.id, f);
2358                 fputc('\n', f);
2359
2360                 if ((r = unit_serialize(u, f, fds)) < 0)
2361                         return r;
2362         }
2363
2364         if (ferror(f))
2365                 return -EIO;
2366
2367         return 0;
2368 }
2369
2370 int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
2371         int r = 0;
2372
2373         assert(m);
2374         assert(f);
2375
2376         log_debug("Deserializing state...");
2377
2378         m->n_deserializing ++;
2379
2380         for (;;) {
2381                 Unit *u;
2382                 char name[UNIT_NAME_MAX+2];
2383
2384                 /* Start marker */
2385                 if (!fgets(name, sizeof(name), f)) {
2386                         if (feof(f))
2387                                 break;
2388
2389                         r = -errno;
2390                         goto finish;
2391                 }
2392
2393                 char_array_0(name);
2394
2395                 if ((r = manager_load_unit(m, strstrip(name), NULL, NULL, &u)) < 0)
2396                         goto finish;
2397
2398                 if ((r = unit_deserialize(u, f, fds)) < 0)
2399                         goto finish;
2400         }
2401
2402         if (ferror(f)) {
2403                 r = -EIO;
2404                 goto finish;
2405         }
2406
2407         r = 0;
2408
2409 finish:
2410         assert(m->n_deserializing > 0);
2411         m->n_deserializing --;
2412
2413         return r;
2414 }
2415
2416 int manager_reload(Manager *m) {
2417         int r, q;
2418         FILE *f;
2419         FDSet *fds;
2420
2421         assert(m);
2422
2423         if ((r = manager_open_serialization(m, &f)) < 0)
2424                 return r;
2425
2426         if (!(fds = fdset_new())) {
2427                 r = -ENOMEM;
2428                 goto finish;
2429         }
2430
2431         if ((r = manager_serialize(m, f, fds)) < 0)
2432                 goto finish;
2433
2434         if (fseeko(f, 0, SEEK_SET) < 0) {
2435                 r = -errno;
2436                 goto finish;
2437         }
2438
2439         /* From here on there is no way back. */
2440         manager_clear_jobs_and_units(m);
2441
2442         /* Find new unit paths */
2443         lookup_paths_free(&m->lookup_paths);
2444         if ((q = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
2445                 r = q;
2446
2447         m->n_deserializing ++;
2448
2449         /* First, enumerate what we can from all config files */
2450         if ((q = manager_enumerate(m)) < 0)
2451                 r = q;
2452
2453         /* Second, deserialize our stored data */
2454         if ((q = manager_deserialize(m, f, fds)) < 0)
2455                 r = q;
2456
2457         fclose(f);
2458         f = NULL;
2459
2460         /* Third, fire things up! */
2461         if ((q = manager_coldplug(m)) < 0)
2462                 r = q;
2463
2464         assert(m->n_deserializing > 0);
2465         m->n_deserializing ++;
2466
2467 finish:
2468         if (f)
2469                 fclose(f);
2470
2471         if (fds)
2472                 fdset_free(fds);
2473
2474         return r;
2475 }
2476
2477 bool manager_is_booting_or_shutting_down(Manager *m) {
2478         Unit *u;
2479
2480         assert(m);
2481
2482         /* Is the initial job still around? */
2483         if (manager_get_job(m, 1))
2484                 return true;
2485
2486         /* Is there a job for the shutdown target? */
2487         if (((u = manager_get_unit(m, SPECIAL_SHUTDOWN_TARGET))))
2488                 return !!u->meta.job;
2489
2490         return false;
2491 }
2492
2493 void manager_reset_maintenance(Manager *m) {
2494         Unit *u;
2495         Iterator i;
2496
2497         assert(m);
2498
2499         HASHMAP_FOREACH(u, m->units, i)
2500                 unit_reset_maintenance(u);
2501 }
2502
2503 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
2504         [MANAGER_SYSTEM] = "system",
2505         [MANAGER_SESSION] = "session"
2506 };
2507
2508 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);