src/manager.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   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
  40 #ifdef HAVE_AUDIT
  41 #include <libaudit.h>
  42 #endif
  43
  44 #include "manager.h"
  45 #include "hashmap.h"
  46 #include "macro.h"
  47 #include "strv.h"
  48 #include "log.h"
  49 #include "util.h"
  50 #include "ratelimit.h"
  51 #include "cgroup.h"
  52 #include "mount-setup.h"
  53 #include "unit-name.h"
  54 #include "dbus-unit.h"
  55 #include "dbus-job.h"
  56 #include "missing.h"
  57 #include "path-lookup.h"
  58 #include "special.h"
  59 #include "bus-errors.h"
  60 #include "exit-status.h"
  61
  62 /* As soon as 16 units are in our GC queue, make sure to run a gc sweep */
  63 #define GC_QUEUE_ENTRIES_MAX 16
  64
  65 /* As soon as 5s passed since a unit was added to our GC queue, make sure to run a gc sweep */
  66 #define GC_QUEUE_USEC_MAX (10*USEC_PER_SEC)
  67
  68 /* Where clients shall send notification messages to */
  69 #define NOTIFY_SOCKET "/org/freedesktop/systemd1/notify"
  70
  71 static int manager_setup_notify(Manager *m) {
  72         union {
  73                 struct sockaddr sa;
  74                 struct sockaddr_un un;
  75         } sa;
  76         struct epoll_event ev;
  77         int one = 1;
  78
  79         assert(m);
  80
  81         m->notify_watch.type = WATCH_NOTIFY;
  82         if ((m->notify_watch.fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) {
  83                 log_error("Failed to allocate notification socket: %m");
  84                 return -errno;
  85         }
  86
  87         zero(sa);
  88         sa.sa.sa_family = AF_UNIX;
  89
  90         if (getpid() != 1)
  91                 snprintf(sa.un.sun_path+1, sizeof(sa.un.sun_path)-1, NOTIFY_SOCKET "/%llu", random_ull());
  92         else
  93                 strncpy(sa.un.sun_path+1, NOTIFY_SOCKET, sizeof(sa.un.sun_path)-1);
  94
  95         if (bind(m->notify_watch.fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + 1 + strlen(sa.un.sun_path+1)) < 0) {
  96                 log_error("bind() failed: %m");
  97                 return -errno;
  98         }
  99
 100         if (setsockopt(m->notify_watch.fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)) < 0) {
 101                 log_error("SO_PASSCRED failed: %m");
 102                 return -errno;
 103         }
 104
 105         zero(ev);
 106         ev.events = EPOLLIN;
 107         ev.data.ptr = &m->notify_watch;
 108
 109         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->notify_watch.fd, &ev) < 0)
 110                 return -errno;
 111
 112         if (!(m->notify_socket = strdup(sa.un.sun_path+1)))
 113                 return -ENOMEM;
 114
 115         log_debug("Using notification socket %s", m->notify_socket);
 116
 117         return 0;
 118 }
 119
 120 static int enable_special_signals(Manager *m) {
 121         char fd;
 122
 123         assert(m);
 124
 125         /* Enable that we get SIGINT on control-alt-del */
 126         if (reboot(RB_DISABLE_CAD) < 0)
 127                 log_warning("Failed to enable ctrl-alt-del handling: %m");
 128
 129         if ((fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY)) < 0)
 130                 log_warning("Failed to open /dev/tty0: %m");
 131         else {
 132                 /* Enable that we get SIGWINCH on kbrequest */
 133                 if (ioctl(fd, KDSIGACCEPT, SIGWINCH) < 0)
 134                         log_warning("Failed to enable kbrequest handling: %s", strerror(errno));
 135
 136                 close_nointr_nofail(fd);
 137         }
 138
 139         return 0;
 140 }
 141
 142 static int manager_setup_signals(Manager *m) {
 143         sigset_t mask;
 144         struct epoll_event ev;
 145         struct sigaction sa;
 146
 147         assert(m);
 148
 149         /* We are not interested in SIGSTOP and friends. */
 150         zero(sa);
 151         sa.sa_handler = SIG_DFL;
 152         sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
 153         assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
 154
 155         assert_se(sigemptyset(&mask) == 0);
 156
 157         sigset_add_many(&mask,
 158                         SIGCHLD,     /* Child died */
 159                         SIGTERM,     /* Reexecute daemon */
 160                         SIGHUP,      /* Reload configuration */
 161                         SIGUSR1,     /* systemd/upstart: reconnect to D-Bus */
 162                         SIGUSR2,     /* systemd: dump status */
 163                         SIGINT,      /* Kernel sends us this on control-alt-del */
 164                         SIGWINCH,    /* Kernel sends us this on kbrequest (alt-arrowup) */
 165                         SIGPWR,      /* Some kernel drivers and upsd send us this on power failure */
 166                         SIGRTMIN+0,  /* systemd: start default.target */
 167                         SIGRTMIN+1,  /* systemd: isolate rescue.target */
 168                         SIGRTMIN+2,  /* systemd: isolate emergency.target */
 169                         SIGRTMIN+3,  /* systemd: start halt.target */
 170                         SIGRTMIN+4,  /* systemd: start poweroff.target */
 171                         SIGRTMIN+5,  /* systemd: start reboot.target */
 172                         SIGRTMIN+6,  /* systemd: start kexec.target */
 173                         SIGRTMIN+13, /* systemd: Immediate halt */
 174                         SIGRTMIN+14, /* systemd: Immediate poweroff */
 175                         SIGRTMIN+15, /* systemd: Immediate reboot */
 176                         SIGRTMIN+16, /* systemd: Immediate kexec */
 177                         -1);
 178         assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
 179
 180         m->signal_watch.type = WATCH_SIGNAL;
 181         if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0)
 182                 return -errno;
 183
 184         zero(ev);
 185         ev.events = EPOLLIN;
 186         ev.data.ptr = &m->signal_watch;
 187
 188         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0)
 189                 return -errno;
 190
 191         if (m->running_as == MANAGER_SYSTEM)
 192                 return enable_special_signals(m);
 193
 194         return 0;
 195 }
 196
 197 int manager_new(ManagerRunningAs running_as, Manager **_m) {
 198         Manager *m;
 199         int r = -ENOMEM;
 200
 201         assert(_m);
 202         assert(running_as >= 0);
 203         assert(running_as < _MANAGER_RUNNING_AS_MAX);
 204
 205         if (!(m = new0(Manager, 1)))
 206                 return -ENOMEM;
 207
 208         dual_timestamp_get(&m->startup_timestamp);
 209
 210         m->running_as = running_as;
 211         m->name_data_slot = m->subscribed_data_slot = -1;
 212         m->exit_code = _MANAGER_EXIT_CODE_INVALID;
 213         m->pin_cgroupfs_fd = -1;
 214
 215 #ifdef HAVE_AUDIT
 216         m->audit_fd = -1;
 217 #endif
 218
 219         m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_fd = m->swap_watch.fd = -1;
 220         m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */
 221
 222         if (!(m->environment = strv_copy(environ)))
 223                 goto fail;
 224
 225         if (!(m->units = hashmap_new(string_hash_func, string_compare_func)))
 226                 goto fail;
 227
 228         if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 229                 goto fail;
 230
 231         if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
 232                 goto fail;
 233
 234         if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
 235                 goto fail;
 236
 237         if (!(m->cgroup_bondings = hashmap_new(string_hash_func, string_compare_func)))
 238                 goto fail;
 239
 240         if (!(m->watch_bus = hashmap_new(string_hash_func, string_compare_func)))
 241                 goto fail;
 242
 243         if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
 244                 goto fail;
 245
 246         if ((r = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
 247                 goto fail;
 248
 249         if ((r = manager_setup_signals(m)) < 0)
 250                 goto fail;
 251
 252         if ((r = manager_setup_cgroup(m)) < 0)
 253                 goto fail;
 254
 255         if ((r = manager_setup_notify(m)) < 0)
 256                 goto fail;
 257
 258         /* Try to connect to the busses, if possible. */
 259         if ((r = bus_init(m)) < 0)
 260                 goto fail;
 261
 262 #ifdef HAVE_AUDIT
 263         if ((m->audit_fd = audit_open()) < 0)
 264                 log_error("Failed to connect to audit log: %m");
 265 #endif
 266
 267         *_m = m;
 268         return 0;
 269
 270 fail:
 271         manager_free(m);
 272         return r;
 273 }
 274
 275 static unsigned manager_dispatch_cleanup_queue(Manager *m) {
 276         Meta *meta;
 277         unsigned n = 0;
 278
 279         assert(m);
 280
 281         while ((meta = m->cleanup_queue)) {
 282                 assert(meta->in_cleanup_queue);
 283
 284                 unit_free((Unit*) meta);
 285                 n++;
 286         }
 287
 288         return n;
 289 }
 290
 291 enum {
 292         GC_OFFSET_IN_PATH,  /* This one is on the path we were travelling */
 293         GC_OFFSET_UNSURE,   /* No clue */
 294         GC_OFFSET_GOOD,     /* We still need this unit */
 295         GC_OFFSET_BAD,      /* We don't need this unit anymore */
 296         _GC_OFFSET_MAX
 297 };
 298
 299 static void unit_gc_sweep(Unit *u, unsigned gc_marker) {
 300         Iterator i;
 301         Unit *other;
 302         bool is_bad;
 303
 304         assert(u);
 305
 306         if (u->meta.gc_marker == gc_marker + GC_OFFSET_GOOD ||
 307             u->meta.gc_marker == gc_marker + GC_OFFSET_BAD ||
 308             u->meta.gc_marker == gc_marker + GC_OFFSET_IN_PATH)
 309                 return;
 310
 311         if (u->meta.in_cleanup_queue)
 312                 goto bad;
 313
 314         if (unit_check_gc(u))
 315                 goto good;
 316
 317         u->meta.gc_marker = gc_marker + GC_OFFSET_IN_PATH;
 318
 319         is_bad = true;
 320
 321         SET_FOREACH(other, u->meta.dependencies[UNIT_REFERENCED_BY], i) {
 322                 unit_gc_sweep(other, gc_marker);
 323
 324                 if (other->meta.gc_marker == gc_marker + GC_OFFSET_GOOD)
 325                         goto good;
 326
 327                 if (other->meta.gc_marker != gc_marker + GC_OFFSET_BAD)
 328                         is_bad = false;
 329         }
 330
 331         if (is_bad)
 332                 goto bad;
 333
 334         /* We were unable to find anything out about this entry, so
 335          * let's investigate it later */
 336         u->meta.gc_marker = gc_marker + GC_OFFSET_UNSURE;
 337         unit_add_to_gc_queue(u);
 338         return;
 339
 340 bad:
 341         /* We definitely know that this one is not useful anymore, so
 342          * let's mark it for deletion */
 343         u->meta.gc_marker = gc_marker + GC_OFFSET_BAD;
 344         unit_add_to_cleanup_queue(u);
 345         return;
 346
 347 good:
 348         u->meta.gc_marker = gc_marker + GC_OFFSET_GOOD;
 349 }
 350
 351 static unsigned manager_dispatch_gc_queue(Manager *m) {
 352         Meta *meta;
 353         unsigned n = 0;
 354         unsigned gc_marker;
 355
 356         assert(m);
 357
 358         if ((m->n_in_gc_queue < GC_QUEUE_ENTRIES_MAX) &&
 359             (m->gc_queue_timestamp <= 0 ||
 360              (m->gc_queue_timestamp + GC_QUEUE_USEC_MAX) > now(CLOCK_MONOTONIC)))
 361                 return 0;
 362
 363         log_debug("Running GC...");
 364
 365         m->gc_marker += _GC_OFFSET_MAX;
 366         if (m->gc_marker + _GC_OFFSET_MAX <= _GC_OFFSET_MAX)
 367                 m->gc_marker = 1;
 368
 369         gc_marker = m->gc_marker;
 370
 371         while ((meta = m->gc_queue)) {
 372                 assert(meta->in_gc_queue);
 373
 374                 unit_gc_sweep((Unit*) meta, gc_marker);
 375
 376                 LIST_REMOVE(Meta, gc_queue, m->gc_queue, meta);
 377                 meta->in_gc_queue = false;
 378
 379                 n++;
 380
 381                 if (meta->gc_marker == gc_marker + GC_OFFSET_BAD ||
 382                     meta->gc_marker == gc_marker + GC_OFFSET_UNSURE) {
 383                         log_debug("Collecting %s", meta->id);
 384                         meta->gc_marker = gc_marker + GC_OFFSET_BAD;
 385                         unit_add_to_cleanup_queue((Unit*) meta);
 386                 }
 387         }
 388
 389         m->n_in_gc_queue = 0;
 390         m->gc_queue_timestamp = 0;
 391
 392         return n;
 393 }
 394
 395 static void manager_clear_jobs_and_units(Manager *m) {
 396         Job *j;
 397         Unit *u;
 398
 399         assert(m);
 400
 401         while ((j = hashmap_first(m->transaction_jobs)))
 402                 job_free(j);
 403
 404         while ((u = hashmap_first(m->units)))
 405                 unit_free(u);
 406
 407         manager_dispatch_cleanup_queue(m);
 408
 409         assert(!m->load_queue);
 410         assert(!m->run_queue);
 411         assert(!m->dbus_unit_queue);
 412         assert(!m->dbus_job_queue);
 413         assert(!m->cleanup_queue);
 414         assert(!m->gc_queue);
 415
 416         assert(hashmap_isempty(m->transaction_jobs));
 417         assert(hashmap_isempty(m->jobs));
 418         assert(hashmap_isempty(m->units));
 419 }
 420
 421 void manager_free(Manager *m) {
 422         UnitType c;
 423
 424         assert(m);
 425
 426         manager_clear_jobs_and_units(m);
 427
 428         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 429                 if (unit_vtable[c]->shutdown)
 430                         unit_vtable[c]->shutdown(m);
 431
 432         /* If we reexecute ourselves, we keep the root cgroup
 433          * around */
 434         manager_shutdown_cgroup(m, m->exit_code != MANAGER_REEXECUTE);
 435
 436         bus_done(m);
 437
 438         hashmap_free(m->units);
 439         hashmap_free(m->jobs);
 440         hashmap_free(m->transaction_jobs);
 441         hashmap_free(m->watch_pids);
 442         hashmap_free(m->watch_bus);
 443
 444         if (m->epoll_fd >= 0)
 445                 close_nointr_nofail(m->epoll_fd);
 446         if (m->signal_watch.fd >= 0)
 447                 close_nointr_nofail(m->signal_watch.fd);
 448         if (m->notify_watch.fd >= 0)
 449                 close_nointr_nofail(m->notify_watch.fd);
 450
 451 #ifdef HAVE_AUDIT
 452         if (m->audit_fd >= 0)
 453                 audit_close(m->audit_fd);
 454 #endif
 455
 456         free(m->notify_socket);
 457         free(m->console);
 458
 459         lookup_paths_free(&m->lookup_paths);
 460         strv_free(m->environment);
 461
 462         hashmap_free(m->cgroup_bondings);
 463         set_free_free(m->unit_path_cache);
 464
 465         free(m);
 466 }
 467
 468 int manager_enumerate(Manager *m) {
 469         int r = 0, q;
 470         UnitType c;
 471
 472         assert(m);
 473
 474         /* Let's ask every type to load all units from disk/kernel
 475          * that it might know */
 476         for (c = 0; c < _UNIT_TYPE_MAX; c++)
 477                 if (unit_vtable[c]->enumerate)
 478                         if ((q = unit_vtable[c]->enumerate(m)) < 0)
 479                                 r = q;
 480
 481         manager_dispatch_load_queue(m);
 482         return r;
 483 }
 484
 485 int manager_coldplug(Manager *m) {
 486         int r = 0, q;
 487         Iterator i;
 488         Unit *u;
 489         char *k;
 490
 491         assert(m);
 492
 493         /* Then, let's set up their initial state. */
 494         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
 495
 496                 /* ignore aliases */
 497                 if (u->meta.id != k)
 498                         continue;
 499
 500                 if ((q = unit_coldplug(u)) < 0)
 501                         r = q;
 502         }
 503
 504         return r;
 505 }
 506
 507 static void manager_build_unit_path_cache(Manager *m) {
 508         char **i;
 509         DIR *d = NULL;
 510         int r;
 511
 512         assert(m);
 513
 514         set_free_free(m->unit_path_cache);
 515
 516         if (!(m->unit_path_cache = set_new(string_hash_func, string_compare_func))) {
 517                 log_error("Failed to allocate unit path cache.");
 518                 return;
 519         }
 520
 521         /* This simply builds a list of files we know exist, so that
 522          * we don't always have to go to disk */
 523
 524         STRV_FOREACH(i, m->lookup_paths.unit_path) {
 525                 struct dirent *de;
 526
 527                 if (!(d = opendir(*i))) {
 528                         log_error("Failed to open directory: %m");
 529                         continue;
 530                 }
 531
 532                 while ((de = readdir(d))) {
 533                         char *p;
 534
 535                         if (ignore_file(de->d_name))
 536                                 continue;
 537
 538                         if (asprintf(&p, "%s/%s", streq(*i, "/") ? "" : *i, de->d_name) < 0) {
 539                                 r = -ENOMEM;
 540                                 goto fail;
 541                         }
 542
 543                         if ((r = set_put(m->unit_path_cache, p)) < 0) {
 544                                 free(p);
 545                                 goto fail;
 546                         }
 547                 }
 548
 549                 closedir(d);
 550                 d = NULL;
 551         }
 552
 553         return;
 554
 555 fail:
 556         log_error("Failed to build unit path cache: %s", strerror(-r));
 557
 558         set_free_free(m->unit_path_cache);
 559         m->unit_path_cache = NULL;
 560
 561         if (d)
 562                 closedir(d);
 563 }
 564
 565 int manager_startup(Manager *m, FILE *serialization, FDSet *fds) {
 566         int r, q;
 567
 568         assert(m);
 569
 570         manager_build_unit_path_cache(m);
 571
 572         /* If we will deserialize make sure that during enumeration
 573          * this is already known, so we increase the counter here
 574          * already */
 575         if (serialization)
 576                 m->n_deserializing ++;
 577
 578         /* First, enumerate what we can from all config files */
 579         r = manager_enumerate(m);
 580
 581         /* Second, deserialize if there is something to deserialize */
 582         if (serialization)
 583                 if ((q = manager_deserialize(m, serialization, fds)) < 0)
 584                         r = q;
 585
 586         /* Third, fire things up! */
 587         if ((q = manager_coldplug(m)) < 0)
 588                 r = q;
 589
 590         if (serialization) {
 591                 assert(m->n_deserializing > 0);
 592                 m->n_deserializing --;
 593         }
 594
 595         return r;
 596 }
 597
 598 static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) {
 599         assert(m);
 600         assert(j);
 601
 602         /* Deletes one job from the transaction */
 603
 604         manager_transaction_unlink_job(m, j, delete_dependencies);
 605
 606         if (!j->installed)
 607                 job_free(j);
 608 }
 609
 610 static void transaction_delete_unit(Manager *m, Unit *u) {
 611         Job *j;
 612
 613         /* Deletes all jobs associated with a certain unit from the
 614          * transaction */
 615
 616         while ((j = hashmap_get(m->transaction_jobs, u)))
 617                 transaction_delete_job(m, j, true);
 618 }
 619
 620 static void transaction_clean_dependencies(Manager *m) {
 621         Iterator i;
 622         Job *j;
 623
 624         assert(m);
 625
 626         /* Drops all dependencies of all installed jobs */
 627
 628         HASHMAP_FOREACH(j, m->jobs, i) {
 629                 while (j->subject_list)
 630                         job_dependency_free(j->subject_list);
 631                 while (j->object_list)
 632                         job_dependency_free(j->object_list);
 633         }
 634
 635         assert(!m->transaction_anchor);
 636 }
 637
 638 static void transaction_abort(Manager *m) {
 639         Job *j;
 640
 641         assert(m);
 642
 643         while ((j = hashmap_first(m->transaction_jobs)))
 644                 if (j->installed)
 645                         transaction_delete_job(m, j, true);
 646                 else
 647                         job_free(j);
 648
 649         assert(hashmap_isempty(m->transaction_jobs));
 650
 651         transaction_clean_dependencies(m);
 652 }
 653
 654 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
 655         JobDependency *l;
 656
 657         assert(m);
 658
 659         /* A recursive sweep through the graph that marks all units
 660          * that matter to the anchor job, i.e. are directly or
 661          * indirectly a dependency of the anchor job via paths that
 662          * are fully marked as mattering. */
 663
 664         if (j)
 665                 l = j->subject_list;
 666         else
 667                 l = m->transaction_anchor;
 668
 669         LIST_FOREACH(subject, l, l) {
 670
 671                 /* This link does not matter */
 672                 if (!l->matters)
 673                         continue;
 674
 675                 /* This unit has already been marked */
 676                 if (l->object->generation == generation)
 677                         continue;
 678
 679                 l->object->matters_to_anchor = true;
 680                 l->object->generation = generation;
 681
 682                 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
 683         }
 684 }
 685
 686 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
 687         JobDependency *l, *last;
 688
 689         assert(j);
 690         assert(other);
 691         assert(j->unit == other->unit);
 692         assert(!j->installed);
 693
 694         /* Merges 'other' into 'j' and then deletes j. */
 695
 696         j->type = t;
 697         j->state = JOB_WAITING;
 698         j->override = j->override || other->override;
 699
 700         j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
 701
 702         /* Patch us in as new owner of the JobDependency objects */
 703         last = NULL;
 704         LIST_FOREACH(subject, l, other->subject_list) {
 705                 assert(l->subject == other);
 706                 l->subject = j;
 707                 last = l;
 708         }
 709
 710         /* Merge both lists */
 711         if (last) {
 712                 last->subject_next = j->subject_list;
 713                 if (j->subject_list)
 714                         j->subject_list->subject_prev = last;
 715                 j->subject_list = other->subject_list;
 716         }
 717
 718         /* Patch us in as new owner of the JobDependency objects */
 719         last = NULL;
 720         LIST_FOREACH(object, l, other->object_list) {
 721                 assert(l->object == other);
 722                 l->object = j;
 723                 last = l;
 724         }
 725
 726         /* Merge both lists */
 727         if (last) {
 728                 last->object_next = j->object_list;
 729                 if (j->object_list)
 730                         j->object_list->object_prev = last;
 731                 j->object_list = other->object_list;
 732         }
 733
 734         /* Kill the other job */
 735         other->subject_list = NULL;
 736         other->object_list = NULL;
 737         transaction_delete_job(m, other, true);
 738 }
 739 static bool job_is_conflicted_by(Job *j) {
 740         JobDependency *l;
 741
 742         assert(j);
 743
 744         /* Returns true if this job is pulled in by a least one
 745          * ConflictedBy dependency. */
 746
 747         LIST_FOREACH(object, l, j->object_list)
 748                 if (l->conflicts)
 749                         return true;
 750
 751         return false;
 752 }
 753
 754 static int delete_one_unmergeable_job(Manager *m, Job *j) {
 755         Job *k;
 756
 757         assert(j);
 758
 759         /* Tries to delete one item in the linked list
 760          * j->transaction_next->transaction_next->... that conflicts
 761          * whith another one, in an attempt to make an inconsistent
 762          * transaction work. */
 763
 764         /* We rely here on the fact that if a merged with b does not
 765          * merge with c, either a or b merge with c neither */
 766         LIST_FOREACH(transaction, j, j)
 767                 LIST_FOREACH(transaction, k, j->transaction_next) {
 768                         Job *d;
 769
 770                         /* Is this one mergeable? Then skip it */
 771                         if (job_type_is_mergeable(j->type, k->type))
 772                                 continue;
 773
 774                         /* Ok, we found two that conflict, let's see if we can
 775                          * drop one of them */
 776                         if (!j->matters_to_anchor && !k->matters_to_anchor) {
 777
 778                                 /* Both jobs don't matter, so let's
 779                                  * find the one that is smarter to
 780                                  * remove. Let's think positive and
 781                                  * rather remove stops then starts --
 782                                  * except if something is being
 783                                  * stopped because it is conflicted by
 784                                  * another unit in which case we
 785                                  * rather remove the start. */
 786
 787                                 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)));
 788                                 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)));
 789
 790                                 if (j->type == JOB_STOP) {
 791
 792                                         if (job_is_conflicted_by(j))
 793                                                 d = k;
 794                                         else
 795                                                 d = j;
 796
 797                                 } else if (k->type == JOB_STOP) {
 798
 799                                         if (job_is_conflicted_by(k))
 800                                                 d = j;
 801                                         else
 802                                                 d = k;
 803                                 } else
 804                                         d = j;
 805
 806                         } else if (!j->matters_to_anchor)
 807                                 d = j;
 808                         else if (!k->matters_to_anchor)
 809                                 d = k;
 810                         else
 811                                 return -ENOEXEC;
 812
 813                         /* Ok, we can drop one, so let's do so. */
 814                         log_debug("Fixing conflicting jobs by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type));
 815                         transaction_delete_job(m, d, true);
 816                         return 0;
 817                 }
 818
 819         return -EINVAL;
 820 }
 821
 822 static int transaction_merge_jobs(Manager *m, DBusError *e) {
 823         Job *j;
 824         Iterator i;
 825         int r;
 826
 827         assert(m);
 828
 829         /* First step, check whether any of the jobs for one specific
 830          * task conflict. If so, try to drop one of them. */
 831         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 832                 JobType t;
 833                 Job *k;
 834
 835                 t = j->type;
 836                 LIST_FOREACH(transaction, k, j->transaction_next) {
 837                         if (job_type_merge(&t, k->type) >= 0)
 838                                 continue;
 839
 840                         /* OK, we could not merge all jobs for this
 841                          * action. Let's see if we can get rid of one
 842                          * of them */
 843
 844                         if ((r = delete_one_unmergeable_job(m, j)) >= 0)
 845                                 /* Ok, we managed to drop one, now
 846                                  * let's ask our callers to call us
 847                                  * again after garbage collecting */
 848                                 return -EAGAIN;
 849
 850                         /* We couldn't merge anything. Failure */
 851                         dbus_set_error(e, BUS_ERROR_TRANSACTION_JOBS_CONFLICTING, "Transaction contains conflicting jobs '%s' and '%s' for %s. Probably contradicting requirement dependencies configured.",
 852                                        job_type_to_string(t), job_type_to_string(k->type), k->unit->meta.id);
 853                         return r;
 854                 }
 855         }
 856
 857         /* Second step, merge the jobs. */
 858         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 859                 JobType t = j->type;
 860                 Job *k;
 861
 862                 /* Merge all transactions */
 863                 LIST_FOREACH(transaction, k, j->transaction_next)
 864                         assert_se(job_type_merge(&t, k->type) == 0);
 865
 866                 /* If an active job is mergeable, merge it too */
 867                 if (j->unit->meta.job)
 868                         job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
 869
 870                 while ((k = j->transaction_next)) {
 871                         if (j->installed) {
 872                                 transaction_merge_and_delete_job(m, k, j, t);
 873                                 j = k;
 874                         } else
 875                                 transaction_merge_and_delete_job(m, j, k, t);
 876                 }
 877
 878                 assert(!j->transaction_next);
 879                 assert(!j->transaction_prev);
 880         }
 881
 882         return 0;
 883 }
 884
 885 static void transaction_drop_redundant(Manager *m) {
 886         bool again;
 887
 888         assert(m);
 889
 890         /* Goes through the transaction and removes all jobs that are
 891          * a noop */
 892
 893         do {
 894                 Job *j;
 895                 Iterator i;
 896
 897                 again = false;
 898
 899                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
 900                         bool changes_something = false;
 901                         Job *k;
 902
 903                         LIST_FOREACH(transaction, k, j) {
 904
 905                                 if (!job_is_anchor(k) &&
 906                                     job_type_is_redundant(k->type, unit_active_state(k->unit)))
 907                                         continue;
 908
 909                                 changes_something = true;
 910                                 break;
 911                         }
 912
 913                         if (changes_something)
 914                                 continue;
 915
 916                         log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type));
 917                         transaction_delete_job(m, j, false);
 918                         again = true;
 919                         break;
 920                 }
 921
 922         } while (again);
 923 }
 924
 925 static bool unit_matters_to_anchor(Unit *u, Job *j) {
 926         assert(u);
 927         assert(!j->transaction_prev);
 928
 929         /* Checks whether at least one of the jobs for this unit
 930          * matters to the anchor. */
 931
 932         LIST_FOREACH(transaction, j, j)
 933                 if (j->matters_to_anchor)
 934                         return true;
 935
 936         return false;
 937 }
 938
 939 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation, DBusError *e) {
 940         Iterator i;
 941         Unit *u;
 942         int r;
 943
 944         assert(m);
 945         assert(j);
 946         assert(!j->transaction_prev);
 947
 948         /* Does a recursive sweep through the ordering graph, looking
 949          * for a cycle. If we find cycle we try to break it. */
 950
 951         /* Have we seen this before? */
 952         if (j->generation == generation) {
 953                 Job *k, *delete;
 954
 955                 /* If the marker is NULL we have been here already and
 956                  * decided the job was loop-free from here. Hence
 957                  * shortcut things and return right-away. */
 958                 if (!j->marker)
 959                         return 0;
 960
 961                 /* So, the marker is not NULL and we already have been
 962                  * here. We have a cycle. Let's try to break it. We go
 963                  * backwards in our path and try to find a suitable
 964                  * job to remove. We use the marker to find our way
 965                  * back, since smart how we are we stored our way back
 966                  * in there. */
 967                 log_warning("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type));
 968
 969                 delete = NULL;
 970                 for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) {
 971
 972                         log_info("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type));
 973
 974                         if (!delete &&
 975                             !k->installed &&
 976                             !unit_matters_to_anchor(k->unit, k)) {
 977                                 /* Ok, we can drop this one, so let's
 978                                  * do so. */
 979                                 delete = k;
 980                         }
 981
 982                         /* Check if this in fact was the beginning of
 983                          * the cycle */
 984                         if (k == j)
 985                                 break;
 986                 }
 987
 988
 989                 if (delete) {
 990                         log_warning("Breaking ordering cycle by deleting job %s/%s", delete->unit->meta.id, job_type_to_string(delete->type));
 991                         transaction_delete_unit(m, delete->unit);
 992                         return -EAGAIN;
 993                 }
 994
 995                 log_error("Unable to break cycle");
 996
 997                 dbus_set_error(e, BUS_ERROR_TRANSACTION_ORDER_IS_CYCLIC, "Transaction order is cyclic. See system logs for details.");
 998                 return -ENOEXEC;
 999         }
1000
1001         /* Make the marker point to where we come from, so that we can
1002          * find our way backwards if we want to break a cycle. We use
1003          * a special marker for the beginning: we point to
1004          * ourselves. */
1005         j->marker = from ? from : j;
1006         j->generation = generation;
1007
1008         /* We assume that the the dependencies are bidirectional, and
1009          * hence can ignore UNIT_AFTER */
1010         SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
1011                 Job *o;
1012
1013                 /* Is there a job for this unit? */
1014                 if (!(o = hashmap_get(m->transaction_jobs, u)))
1015
1016                         /* Ok, there is no job for this in the
1017                          * transaction, but maybe there is already one
1018                          * running? */
1019                         if (!(o = u->meta.job))
1020                                 continue;
1021
1022                 if ((r = transaction_verify_order_one(m, o, j, generation, e)) < 0)
1023                         return r;
1024         }
1025
1026         /* Ok, let's backtrack, and remember that this entry is not on
1027          * our path anymore. */
1028         j->marker = NULL;
1029
1030         return 0;
1031 }
1032
1033 static int transaction_verify_order(Manager *m, unsigned *generation, DBusError *e) {
1034         Job *j;
1035         int r;
1036         Iterator i;
1037         unsigned g;
1038
1039         assert(m);
1040         assert(generation);
1041
1042         /* Check if the ordering graph is cyclic. If it is, try to fix
1043          * that up by dropping one of the jobs. */
1044
1045         g = (*generation)++;
1046
1047         HASHMAP_FOREACH(j, m->transaction_jobs, i)
1048                 if ((r = transaction_verify_order_one(m, j, NULL, g, e)) < 0)
1049                         return r;
1050
1051         return 0;
1052 }
1053
1054 static void transaction_collect_garbage(Manager *m) {
1055         bool again;
1056
1057         assert(m);
1058
1059         /* Drop jobs that are not required by any other job */
1060
1061         do {
1062                 Iterator i;
1063                 Job *j;
1064
1065                 again = false;
1066
1067                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1068                         if (j->object_list)
1069                                 continue;
1070
1071                         log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type));
1072                         transaction_delete_job(m, j, true);
1073                         again = true;
1074                         break;
1075                 }
1076
1077         } while (again);
1078 }
1079
1080 static int transaction_is_destructive(Manager *m, DBusError *e) {
1081         Iterator i;
1082         Job *j;
1083
1084         assert(m);
1085
1086         /* Checks whether applying this transaction means that
1087          * existing jobs would be replaced */
1088
1089         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1090
1091                 /* Assume merged */
1092                 assert(!j->transaction_prev);
1093                 assert(!j->transaction_next);
1094
1095                 if (j->unit->meta.job &&
1096                     j->unit->meta.job != j &&
1097                     !job_type_is_superset(j->type, j->unit->meta.job->type)) {
1098
1099                         dbus_set_error(e, BUS_ERROR_TRANSACTION_IS_DESTRUCTIVE, "Transaction is destructive.");
1100                         return -EEXIST;
1101                 }
1102         }
1103
1104         return 0;
1105 }
1106
1107 static void transaction_minimize_impact(Manager *m) {
1108         bool again;
1109         assert(m);
1110
1111         /* Drops all unnecessary jobs that reverse already active jobs
1112          * or that stop a running service. */
1113
1114         do {
1115                 Job *j;
1116                 Iterator i;
1117
1118                 again = false;
1119
1120                 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1121                         LIST_FOREACH(transaction, j, j) {
1122                                 bool stops_running_service, changes_existing_job;
1123
1124                                 /* If it matters, we shouldn't drop it */
1125                                 if (j->matters_to_anchor)
1126                                         continue;
1127
1128                                 /* Would this stop a running service?
1129                                  * Would this change an existing job?
1130                                  * If so, let's drop this entry */
1131
1132                                 stops_running_service =
1133                                         j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
1134
1135                                 changes_existing_job =
1136                                         j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->type);
1137
1138                                 if (!stops_running_service && !changes_existing_job)
1139                                         continue;
1140
1141                                 if (stops_running_service)
1142                                         log_info("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type));
1143
1144                                 if (changes_existing_job)
1145                                         log_info("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type));
1146
1147                                 /* Ok, let's get rid of this */
1148                                 log_info("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type));
1149
1150                                 transaction_delete_job(m, j, true);
1151                                 again = true;
1152                                 break;
1153                         }
1154
1155                         if (again)
1156                                 break;
1157                 }
1158
1159         } while (again);
1160 }
1161
1162 static int transaction_apply(Manager *m) {
1163         Iterator i;
1164         Job *j;
1165         int r;
1166
1167         /* Moves the transaction jobs to the set of active jobs */
1168
1169         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1170                 /* Assume merged */
1171                 assert(!j->transaction_prev);
1172                 assert(!j->transaction_next);
1173
1174                 if (j->installed)
1175                         continue;
1176
1177                 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
1178                         goto rollback;
1179         }
1180
1181         while ((j = hashmap_steal_first(m->transaction_jobs))) {
1182                 if (j->installed)
1183                         continue;
1184
1185                 if (j->unit->meta.job)
1186                         job_free(j->unit->meta.job);
1187
1188                 j->unit->meta.job = j;
1189                 j->installed = true;
1190                 m->n_installed_jobs ++;
1191
1192                 /* We're fully installed. Now let's free data we don't
1193                  * need anymore. */
1194
1195                 assert(!j->transaction_next);
1196                 assert(!j->transaction_prev);
1197
1198                 job_add_to_run_queue(j);
1199                 job_add_to_dbus_queue(j);
1200                 job_start_timer(j);
1201
1202                 log_debug("Installed new job %s/%s as %u", j->unit->meta.id, job_type_to_string(j->type), (unsigned) j->id);
1203         }
1204
1205         /* As last step, kill all remaining job dependencies. */
1206         transaction_clean_dependencies(m);
1207
1208         return 0;
1209
1210 rollback:
1211
1212         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1213                 if (j->installed)
1214                         continue;
1215
1216                 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1217         }
1218
1219         return r;
1220 }
1221
1222 static int transaction_activate(Manager *m, JobMode mode, DBusError *e) {
1223         int r;
1224         unsigned generation = 1;
1225
1226         assert(m);
1227
1228         /* This applies the changes recorded in transaction_jobs to
1229          * the actual list of jobs, if possible. */
1230
1231         /* First step: figure out which jobs matter */
1232         transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1233
1234         /* Second step: Try not to stop any running services if
1235          * we don't have to. Don't try to reverse running
1236          * jobs if we don't have to. */
1237         if (mode != JOB_ISOLATE)
1238                 transaction_minimize_impact(m);
1239
1240         /* Third step: Drop redundant jobs */
1241         transaction_drop_redundant(m);
1242
1243         for (;;) {
1244                 /* Fourth step: Let's remove unneeded jobs that might
1245                  * be lurking. */
1246                 transaction_collect_garbage(m);
1247
1248                 /* Fifth step: verify order makes sense and correct
1249                  * cycles if necessary and possible */
1250                 if ((r = transaction_verify_order(m, &generation, e)) >= 0)
1251                         break;
1252
1253                 if (r != -EAGAIN) {
1254                         log_warning("Requested transaction contains an unfixable cyclic ordering dependency: %s", bus_error(e, r));
1255                         goto rollback;
1256                 }
1257
1258                 /* Let's see if the resulting transaction ordering
1259                  * graph is still cyclic... */
1260         }
1261
1262         for (;;) {
1263                 /* Sixth step: let's drop unmergeable entries if
1264                  * necessary and possible, merge entries we can
1265                  * merge */
1266                 if ((r = transaction_merge_jobs(m, e)) >= 0)
1267                         break;
1268
1269                 if (r != -EAGAIN) {
1270                         log_warning("Requested transaction contains unmergable jobs: %s", bus_error(e, r));
1271                         goto rollback;
1272                 }
1273
1274                 /* Seventh step: an entry got dropped, let's garbage
1275                  * collect its dependencies. */
1276                 transaction_collect_garbage(m);
1277
1278                 /* Let's see if the resulting transaction still has
1279                  * unmergeable entries ... */
1280         }
1281
1282         /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1283         transaction_drop_redundant(m);
1284
1285         /* Ninth step: check whether we can actually apply this */
1286         if (mode == JOB_FAIL)
1287                 if ((r = transaction_is_destructive(m, e)) < 0) {
1288                         log_notice("Requested transaction contradicts existing jobs: %s", bus_error(e, r));
1289                         goto rollback;
1290                 }
1291
1292         /* Tenth step: apply changes */
1293         if ((r = transaction_apply(m)) < 0) {
1294                 log_warning("Failed to apply transaction: %s", strerror(-r));
1295                 goto rollback;
1296         }
1297
1298         assert(hashmap_isempty(m->transaction_jobs));
1299         assert(!m->transaction_anchor);
1300
1301         return 0;
1302
1303 rollback:
1304         transaction_abort(m);
1305         return r;
1306 }
1307
1308 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1309         Job *j, *f;
1310
1311         assert(m);
1312         assert(unit);
1313
1314         /* Looks for an axisting prospective job and returns that. If
1315          * it doesn't exist it is created and added to the prospective
1316          * jobs list. */
1317
1318         f = hashmap_get(m->transaction_jobs, unit);
1319
1320         LIST_FOREACH(transaction, j, f) {
1321                 assert(j->unit == unit);
1322
1323                 if (j->type == type) {
1324                         if (is_new)
1325                                 *is_new = false;
1326                         return j;
1327                 }
1328         }
1329
1330         if (unit->meta.job && unit->meta.job->type == type)
1331                 j = unit->meta.job;
1332         else if (!(j = job_new(m, type, unit)))
1333                 return NULL;
1334
1335         j->generation = 0;
1336         j->marker = NULL;
1337         j->matters_to_anchor = false;
1338         j->override = override;
1339
1340         LIST_PREPEND(Job, transaction, f, j);
1341
1342         if (hashmap_replace(m->transaction_jobs, unit, f) < 0) {
1343                 job_free(j);
1344                 return NULL;
1345         }
1346
1347         if (is_new)
1348                 *is_new = true;
1349
1350         log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1351
1352         return j;
1353 }
1354
1355 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1356         assert(m);
1357         assert(j);
1358
1359         if (j->transaction_prev)
1360                 j->transaction_prev->transaction_next = j->transaction_next;
1361         else if (j->transaction_next)
1362                 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1363         else
1364                 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1365
1366         if (j->transaction_next)
1367                 j->transaction_next->transaction_prev = j->transaction_prev;
1368
1369         j->transaction_prev = j->transaction_next = NULL;
1370
1371         while (j->subject_list)
1372                 job_dependency_free(j->subject_list);
1373
1374         while (j->object_list) {
1375                 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1376
1377                 job_dependency_free(j->object_list);
1378
1379                 if (other && delete_dependencies) {
1380                         log_debug("Deleting job %s/%s as dependency of job %s/%s",
1381                                   other->unit->meta.id, job_type_to_string(other->type),
1382                                   j->unit->meta.id, job_type_to_string(j->type));
1383                         transaction_delete_job(m, other, delete_dependencies);
1384                 }
1385         }
1386 }
1387
1388 static int transaction_add_job_and_dependencies(
1389                 Manager *m,
1390                 JobType type,
1391                 Unit *unit,
1392                 Job *by,
1393                 bool matters,
1394                 bool override,
1395                 bool conflicts,
1396                 DBusError *e,
1397                 Job **_ret) {
1398         Job *ret;
1399         Iterator i;
1400         Unit *dep;
1401         int r;
1402         bool is_new;
1403
1404         assert(m);
1405         assert(type < _JOB_TYPE_MAX);
1406         assert(unit);
1407
1408         if (unit->meta.load_state != UNIT_LOADED &&
1409             unit->meta.load_state != UNIT_ERROR &&
1410             unit->meta.load_state != UNIT_MASKED) {
1411                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED, "Unit %s is not loaded properly.", unit->meta.id);
1412                 return -EINVAL;
1413         }
1414
1415         if (type != JOB_STOP && unit->meta.load_state == UNIT_ERROR) {
1416                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED,
1417                                "Unit %s failed to load: %s. "
1418                                "See system logs and 'systemctl status' for details.",
1419                                unit->meta.id,
1420                                strerror(-unit->meta.load_error));
1421                 return -EINVAL;
1422         }
1423
1424         if (type != JOB_STOP && unit->meta.load_state == UNIT_MASKED) {
1425                 dbus_set_error(e, BUS_ERROR_MASKED, "Unit %s is masked.", unit->meta.id);
1426                 return -EINVAL;
1427         }
1428
1429         if (!unit_job_is_applicable(unit, type)) {
1430                 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);
1431                 return -EBADR;
1432         }
1433
1434         /* First add the job. */
1435         if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1436                 return -ENOMEM;
1437
1438         /* Then, add a link to the job. */
1439         if (!job_dependency_new(by, ret, matters, conflicts))
1440                 return -ENOMEM;
1441
1442         if (is_new) {
1443                 /* Finally, recursively add in all dependencies. */
1444                 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1445                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1446                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1447                                         goto fail;
1448
1449                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1450                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, false, e, NULL)) < 0 && r != -EBADR) {
1451                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1452
1453                                         if (e)
1454                                                 dbus_error_free(e);
1455                                 }
1456
1457                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1458                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, false, e, NULL)) < 0) {
1459                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1460
1461                                         if (e)
1462                                                 dbus_error_free(e);
1463                                 }
1464
1465                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1466                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1467                                         goto fail;
1468
1469                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1470                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, false, e, NULL)) < 0 && r != -EBADR) {
1471                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1472
1473                                         if (e)
1474                                                 dbus_error_free(e);
1475                                 }
1476
1477                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1478                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, true, e, NULL)) < 0 && r != -EBADR)
1479                                         goto fail;
1480
1481                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTED_BY], i)
1482                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1483                                         goto fail;
1484
1485                 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1486
1487                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1488                                 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1489                                         goto fail;
1490                 }
1491
1492                 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1493         }
1494
1495         if (_ret)
1496                 *_ret = ret;
1497
1498         return 0;
1499
1500 fail:
1501         return r;
1502 }
1503
1504 static int transaction_add_isolate_jobs(Manager *m) {
1505         Iterator i;
1506         Unit *u;
1507         char *k;
1508         int r;
1509
1510         assert(m);
1511
1512         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
1513
1514                 /* ignore aliases */
1515                 if (u->meta.id != k)
1516                         continue;
1517
1518                 if (UNIT_VTABLE(u)->no_isolate)
1519                         continue;
1520
1521                 /* No need to stop inactive jobs */
1522                 if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(u)))
1523                         continue;
1524
1525                 /* Is there already something listed for this? */
1526                 if (hashmap_get(m->transaction_jobs, u))
1527                         continue;
1528
1529                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, u, NULL, true, false, false, NULL, NULL)) < 0)
1530                         log_warning("Cannot add isolate job for unit %s, ignoring: %s", u->meta.id, strerror(-r));
1531         }
1532
1533         return 0;
1534 }
1535
1536 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, DBusError *e, Job **_ret) {
1537         int r;
1538         Job *ret;
1539
1540         assert(m);
1541         assert(type < _JOB_TYPE_MAX);
1542         assert(unit);
1543         assert(mode < _JOB_MODE_MAX);
1544
1545         if (mode == JOB_ISOLATE && type != JOB_START) {
1546                 dbus_set_error(e, BUS_ERROR_INVALID_JOB_MODE, "Isolate is only valid for start.");
1547                 return -EINVAL;
1548         }
1549
1550         if (mode == JOB_ISOLATE && !unit->meta.allow_isolate) {
1551                 dbus_set_error(e, BUS_ERROR_NO_ISOLATION, "Operation refused, unit may not be isolated.");
1552                 return -EPERM;
1553         }
1554
1555         log_debug("Trying to enqueue job %s/%s/%s", unit->meta.id, job_type_to_string(type), job_mode_to_string(mode));
1556
1557         if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, false, e, &ret)) < 0) {
1558                 transaction_abort(m);
1559                 return r;
1560         }
1561
1562         if (mode == JOB_ISOLATE)
1563                 if ((r = transaction_add_isolate_jobs(m)) < 0) {
1564                         transaction_abort(m);
1565                         return r;
1566                 }
1567
1568         if ((r = transaction_activate(m, mode, e)) < 0)
1569                 return r;
1570
1571         log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id);
1572
1573         if (_ret)
1574                 *_ret = ret;
1575
1576         return 0;
1577 }
1578
1579 int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, DBusError *e, Job **_ret) {
1580         Unit *unit;
1581         int r;
1582
1583         assert(m);
1584         assert(type < _JOB_TYPE_MAX);
1585         assert(name);
1586         assert(mode < _JOB_MODE_MAX);
1587
1588         if ((r = manager_load_unit(m, name, NULL, NULL, &unit)) < 0)
1589                 return r;
1590
1591         return manager_add_job(m, type, unit, mode, override, e, _ret);
1592 }
1593
1594 Job *manager_get_job(Manager *m, uint32_t id) {
1595         assert(m);
1596
1597         return hashmap_get(m->jobs, UINT32_TO_PTR(id));
1598 }
1599
1600 Unit *manager_get_unit(Manager *m, const char *name) {
1601         assert(m);
1602         assert(name);
1603
1604         return hashmap_get(m->units, name);
1605 }
1606
1607 unsigned manager_dispatch_load_queue(Manager *m) {
1608         Meta *meta;
1609         unsigned n = 0;
1610
1611         assert(m);
1612
1613         /* Make sure we are not run recursively */
1614         if (m->dispatching_load_queue)
1615                 return 0;
1616
1617         m->dispatching_load_queue = true;
1618
1619         /* Dispatches the load queue. Takes a unit from the queue and
1620          * tries to load its data until the queue is empty */
1621
1622         while ((meta = m->load_queue)) {
1623                 assert(meta->in_load_queue);
1624
1625                 unit_load((Unit*) meta);
1626                 n++;
1627         }
1628
1629         m->dispatching_load_queue = false;
1630         return n;
1631 }
1632
1633 int manager_load_unit_prepare(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1634         Unit *ret;
1635         int r;
1636
1637         assert(m);
1638         assert(name || path);
1639
1640         /* This will prepare the unit for loading, but not actually
1641          * load anything from disk. */
1642
1643         if (path && !is_path(path)) {
1644                 dbus_set_error(e, BUS_ERROR_INVALID_PATH, "Path %s is not absolute.", path);
1645                 return -EINVAL;
1646         }
1647
1648         if (!name)
1649                 name = file_name_from_path(path);
1650
1651         if (!unit_name_is_valid(name, false)) {
1652                 dbus_set_error(e, BUS_ERROR_INVALID_NAME, "Unit name %s is not valid.", name);
1653                 return -EINVAL;
1654         }
1655
1656         if ((ret = manager_get_unit(m, name))) {
1657                 *_ret = ret;
1658                 return 1;
1659         }
1660
1661         if (!(ret = unit_new(m)))
1662                 return -ENOMEM;
1663
1664         if (path)
1665                 if (!(ret->meta.fragment_path = strdup(path))) {
1666                         unit_free(ret);
1667                         return -ENOMEM;
1668                 }
1669
1670         if ((r = unit_add_name(ret, name)) < 0) {
1671                 unit_free(ret);
1672                 return r;
1673         }
1674
1675         unit_add_to_load_queue(ret);
1676         unit_add_to_dbus_queue(ret);
1677         unit_add_to_gc_queue(ret);
1678
1679         if (_ret)
1680                 *_ret = ret;
1681
1682         return 0;
1683 }
1684
1685 int manager_load_unit(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1686         int r;
1687
1688         assert(m);
1689
1690         /* This will load the service information files, but not actually
1691          * start any services or anything. */
1692
1693         if ((r = manager_load_unit_prepare(m, name, path, e, _ret)) != 0)
1694                 return r;
1695
1696         manager_dispatch_load_queue(m);
1697
1698         if (_ret)
1699                 *_ret = unit_follow_merge(*_ret);
1700
1701         return 0;
1702 }
1703
1704 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1705         Iterator i;
1706         Job *j;
1707
1708         assert(s);
1709         assert(f);
1710
1711         HASHMAP_FOREACH(j, s->jobs, i)
1712                 job_dump(j, f, prefix);
1713 }
1714
1715 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1716         Iterator i;
1717         Unit *u;
1718         const char *t;
1719
1720         assert(s);
1721         assert(f);
1722
1723         HASHMAP_FOREACH_KEY(u, t, s->units, i)
1724                 if (u->meta.id == t)
1725                         unit_dump(u, f, prefix);
1726 }
1727
1728 void manager_clear_jobs(Manager *m) {
1729         Job *j;
1730
1731         assert(m);
1732
1733         transaction_abort(m);
1734
1735         while ((j = hashmap_first(m->jobs)))
1736                 job_free(j);
1737 }
1738
1739 unsigned manager_dispatch_run_queue(Manager *m) {
1740         Job *j;
1741         unsigned n = 0;
1742
1743         if (m->dispatching_run_queue)
1744                 return 0;
1745
1746         m->dispatching_run_queue = true;
1747
1748         while ((j = m->run_queue)) {
1749                 assert(j->installed);
1750                 assert(j->in_run_queue);
1751
1752                 job_run_and_invalidate(j);
1753                 n++;
1754         }
1755
1756         m->dispatching_run_queue = false;
1757         return n;
1758 }
1759
1760 unsigned manager_dispatch_dbus_queue(Manager *m) {
1761         Job *j;
1762         Meta *meta;
1763         unsigned n = 0;
1764
1765         assert(m);
1766
1767         if (m->dispatching_dbus_queue)
1768                 return 0;
1769
1770         m->dispatching_dbus_queue = true;
1771
1772         while ((meta = m->dbus_unit_queue)) {
1773                 assert(meta->in_dbus_queue);
1774
1775                 bus_unit_send_change_signal((Unit*) meta);
1776                 n++;
1777         }
1778
1779         while ((j = m->dbus_job_queue)) {
1780                 assert(j->in_dbus_queue);
1781
1782                 bus_job_send_change_signal(j);
1783                 n++;
1784         }
1785
1786         m->dispatching_dbus_queue = false;
1787         return n;
1788 }
1789
1790 static int manager_process_notify_fd(Manager *m) {
1791         ssize_t n;
1792
1793         assert(m);
1794
1795         for (;;) {
1796                 char buf[4096];
1797                 struct msghdr msghdr;
1798                 struct iovec iovec;
1799                 struct ucred *ucred;
1800                 union {
1801                         struct cmsghdr cmsghdr;
1802                         uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
1803                 } control;
1804                 Unit *u;
1805                 char **tags;
1806
1807                 zero(iovec);
1808                 iovec.iov_base = buf;
1809                 iovec.iov_len = sizeof(buf)-1;
1810
1811                 zero(control);
1812                 zero(msghdr);
1813                 msghdr.msg_iov = &iovec;
1814                 msghdr.msg_iovlen = 1;
1815                 msghdr.msg_control = &control;
1816                 msghdr.msg_controllen = sizeof(control);
1817
1818                 if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) <= 0) {
1819                         if (n >= 0)
1820                                 return -EIO;
1821
1822                         if (errno == EAGAIN || errno == EINTR)
1823                                 break;
1824
1825                         return -errno;
1826                 }
1827
1828                 if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
1829                     control.cmsghdr.cmsg_level != SOL_SOCKET ||
1830                     control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
1831                     control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
1832                         log_warning("Received notify message without credentials. Ignoring.");
1833                         continue;
1834                 }
1835
1836                 ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
1837
1838                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(ucred->pid))))
1839                         if (!(u = cgroup_unit_by_pid(m, ucred->pid))) {
1840                                 log_warning("Cannot find unit for notify message of PID %lu.", (unsigned long) ucred->pid);
1841                                 continue;
1842                         }
1843
1844                 assert((size_t) n < sizeof(buf));
1845                 buf[n] = 0;
1846                 if (!(tags = strv_split(buf, "\n\r")))
1847                         return -ENOMEM;
1848
1849                 log_debug("Got notification message for unit %s", u->meta.id);
1850
1851                 if (UNIT_VTABLE(u)->notify_message)
1852                         UNIT_VTABLE(u)->notify_message(u, ucred->pid, tags);
1853
1854                 strv_free(tags);
1855         }
1856
1857         return 0;
1858 }
1859
1860 static int manager_dispatch_sigchld(Manager *m) {
1861         assert(m);
1862
1863         for (;;) {
1864                 siginfo_t si;
1865                 Unit *u;
1866                 int r;
1867
1868                 zero(si);
1869
1870                 /* First we call waitd() for a PID and do not reap the
1871                  * zombie. That way we can still access /proc/$PID for
1872                  * it while it is a zombie. */
1873                 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1874
1875                         if (errno == ECHILD)
1876                                 break;
1877
1878                         if (errno == EINTR)
1879                                 continue;
1880
1881                         return -errno;
1882                 }
1883
1884                 if (si.si_pid <= 0)
1885                         break;
1886
1887                 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1888                         char *name = NULL;
1889
1890                         get_process_name(si.si_pid, &name);
1891                         log_debug("Got SIGCHLD for process %lu (%s)", (unsigned long) si.si_pid, strna(name));
1892                         free(name);
1893                 }
1894
1895                 /* Let's flush any message the dying child might still
1896                  * have queued for us. This ensures that the process
1897                  * still exists in /proc so that we can figure out
1898                  * which cgroup and hence unit it belongs to. */
1899                 if ((r = manager_process_notify_fd(m)) < 0)
1900                         return r;
1901
1902                 /* And now figure out the unit this belongs to */
1903                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(si.si_pid))))
1904                         u = cgroup_unit_by_pid(m, si.si_pid);
1905
1906                 /* And now, we actually reap the zombie. */
1907                 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1908                         if (errno == EINTR)
1909                                 continue;
1910
1911                         return -errno;
1912                 }
1913
1914                 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1915                         continue;
1916
1917                 log_debug("Child %lu died (code=%s, status=%i/%s)",
1918                           (long unsigned) si.si_pid,
1919                           sigchld_code_to_string(si.si_code),
1920                           si.si_status,
1921                           strna(si.si_code == CLD_EXITED
1922                                 ? exit_status_to_string(si.si_status, EXIT_STATUS_FULL)
1923                                 : signal_to_string(si.si_status)));
1924
1925                 if (!u)
1926                         continue;
1927
1928                 log_debug("Child %lu belongs to %s", (long unsigned) si.si_pid, u->meta.id);
1929
1930                 hashmap_remove(m->watch_pids, LONG_TO_PTR(si.si_pid));
1931                 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1932         }
1933
1934         return 0;
1935 }
1936
1937 static int manager_start_target(Manager *m, const char *name, JobMode mode) {
1938         int r;
1939         DBusError error;
1940
1941         dbus_error_init(&error);
1942
1943         log_info("Activating special unit %s", name);
1944
1945         if ((r = manager_add_job_by_name(m, JOB_START, name, mode, true, &error, NULL)) < 0)
1946                 log_error("Failed to enqueue %s job: %s", name, bus_error(&error, r));
1947
1948         dbus_error_free(&error);
1949
1950         return r;
1951 }
1952
1953 static int manager_process_signal_fd(Manager *m) {
1954         ssize_t n;
1955         struct signalfd_siginfo sfsi;
1956         bool sigchld = false;
1957
1958         assert(m);
1959
1960         for (;;) {
1961                 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1962
1963                         if (n >= 0)
1964                                 return -EIO;
1965
1966                         if (errno == EINTR || errno == EAGAIN)
1967                                 break;
1968
1969                         return -errno;
1970                 }
1971
1972                 log_debug("Received SIG%s", strna(signal_to_string(sfsi.ssi_signo)));
1973
1974                 switch (sfsi.ssi_signo) {
1975
1976                 case SIGCHLD:
1977                         sigchld = true;
1978                         break;
1979
1980                 case SIGTERM:
1981                         if (m->running_as == MANAGER_SYSTEM) {
1982                                 /* This is for compatibility with the
1983                                  * original sysvinit */
1984                                 m->exit_code = MANAGER_REEXECUTE;
1985                                 break;
1986                         }
1987
1988                         /* Fall through */
1989
1990                 case SIGINT:
1991                         if (m->running_as == MANAGER_SYSTEM) {
1992                                 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET, JOB_REPLACE);
1993                                 break;
1994                         }
1995
1996                         /* Run the exit target if there is one, if not, just exit. */
1997                         if (manager_start_target(m, SPECIAL_EXIT_TARGET, JOB_REPLACE) < 0) {
1998                                 m->exit_code = MANAGER_EXIT;
1999                                 return 0;
2000                         }
2001
2002                         break;
2003
2004                 case SIGWINCH:
2005                         if (m->running_as == MANAGER_SYSTEM)
2006                                 manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE);
2007
2008                         /* This is a nop on non-init */
2009                         break;
2010
2011                 case SIGPWR:
2012                         if (m->running_as == MANAGER_SYSTEM)
2013                                 manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE);
2014
2015                         /* This is a nop on non-init */
2016                         break;
2017
2018                 case SIGUSR1: {
2019                         Unit *u;
2020
2021                         u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
2022
2023                         if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
2024                                 log_info("Trying to reconnect to bus...");
2025                                 bus_init(m);
2026                         }
2027
2028                         if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
2029                                 log_info("Loading D-Bus service...");
2030                                 manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE);
2031                         }
2032
2033                         break;
2034                 }
2035
2036                 case SIGUSR2: {
2037                         FILE *f;
2038                         char *dump = NULL;
2039                         size_t size;
2040
2041                         if (!(f = open_memstream(&dump, &size))) {
2042                                 log_warning("Failed to allocate memory stream.");
2043                                 break;
2044                         }
2045
2046                         manager_dump_units(m, f, "\t");
2047                         manager_dump_jobs(m, f, "\t");
2048
2049                         if (ferror(f)) {
2050                                 fclose(f);
2051                                 free(dump);
2052                                 log_warning("Failed to write status stream");
2053                                 break;
2054                         }
2055
2056                         fclose(f);
2057                         log_dump(LOG_INFO, dump);
2058                         free(dump);
2059
2060                         break;
2061                 }
2062
2063                 case SIGHUP:
2064                         m->exit_code = MANAGER_RELOAD;
2065                         break;
2066
2067                 default: {
2068                         /* Starting SIGRTMIN+0 */
2069                         static const char * const target_table[] = {
2070                                 [0] = SPECIAL_DEFAULT_TARGET,
2071                                 [1] = SPECIAL_RESCUE_TARGET,
2072                                 [2] = SPECIAL_EMERGENCY_TARGET,
2073                                 [3] = SPECIAL_HALT_TARGET,
2074                                 [4] = SPECIAL_POWEROFF_TARGET,
2075                                 [5] = SPECIAL_REBOOT_TARGET,
2076                                 [6] = SPECIAL_KEXEC_TARGET
2077                         };
2078
2079                         /* Starting SIGRTMIN+13, so that target halt and system halt are 10 apart */
2080                         static const ManagerExitCode code_table[] = {
2081                                 [0] = MANAGER_HALT,
2082                                 [1] = MANAGER_POWEROFF,
2083                                 [2] = MANAGER_REBOOT,
2084                                 [3] = MANAGER_KEXEC
2085                         };
2086
2087                         if ((int) sfsi.ssi_signo >= SIGRTMIN+0 &&
2088                             (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(target_table)) {
2089                                 manager_start_target(m, target_table[sfsi.ssi_signo - SIGRTMIN],
2090                                                      (sfsi.ssi_signo == 1 || sfsi.ssi_signo == 2) ? JOB_ISOLATE : JOB_REPLACE);
2091                                 break;
2092                         }
2093
2094                         if ((int) sfsi.ssi_signo >= SIGRTMIN+13 &&
2095                             (int) sfsi.ssi_signo < SIGRTMIN+13+(int) ELEMENTSOF(code_table)) {
2096                                 m->exit_code = code_table[sfsi.ssi_signo - SIGRTMIN - 13];
2097                                 break;
2098                         }
2099
2100                         log_warning("Got unhandled signal <%s>.", strna(signal_to_string(sfsi.ssi_signo)));
2101                 }
2102                 }
2103         }
2104
2105         if (sigchld)
2106                 return manager_dispatch_sigchld(m);
2107
2108         return 0;
2109 }
2110
2111 static int process_event(Manager *m, struct epoll_event *ev) {
2112         int r;
2113         Watch *w;
2114
2115         assert(m);
2116         assert(ev);
2117
2118         assert(w = ev->data.ptr);
2119
2120         switch (w->type) {
2121
2122         case WATCH_SIGNAL:
2123
2124                 /* An incoming signal? */
2125                 if (ev->events != EPOLLIN)
2126                         return -EINVAL;
2127
2128                 if ((r = manager_process_signal_fd(m)) < 0)
2129                         return r;
2130
2131                 break;
2132
2133         case WATCH_NOTIFY:
2134
2135                 /* An incoming daemon notification event? */
2136                 if (ev->events != EPOLLIN)
2137                         return -EINVAL;
2138
2139                 if ((r = manager_process_notify_fd(m)) < 0)
2140                         return r;
2141
2142                 break;
2143
2144         case WATCH_FD:
2145
2146                 /* Some fd event, to be dispatched to the units */
2147                 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
2148                 break;
2149
2150         case WATCH_UNIT_TIMER:
2151         case WATCH_JOB_TIMER: {
2152                 uint64_t v;
2153                 ssize_t k;
2154
2155                 /* Some timer event, to be dispatched to the units */
2156                 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
2157
2158                         if (k < 0 && (errno == EINTR || errno == EAGAIN))
2159                                 break;
2160
2161                         return k < 0 ? -errno : -EIO;
2162                 }
2163
2164                 if (w->type == WATCH_UNIT_TIMER)
2165                         UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
2166                 else
2167                         job_timer_event(w->data.job, v, w);
2168                 break;
2169         }
2170
2171         case WATCH_MOUNT:
2172                 /* Some mount table change, intended for the mount subsystem */
2173                 mount_fd_event(m, ev->events);
2174                 break;
2175
2176         case WATCH_SWAP:
2177                 /* Some swap table change, intended for the swap subsystem */
2178                 swap_fd_event(m, ev->events);
2179                 break;
2180
2181         case WATCH_UDEV:
2182                 /* Some notification from udev, intended for the device subsystem */
2183                 device_fd_event(m, ev->events);
2184                 break;
2185
2186         case WATCH_DBUS_WATCH:
2187                 bus_watch_event(m, w, ev->events);
2188                 break;
2189
2190         case WATCH_DBUS_TIMEOUT:
2191                 bus_timeout_event(m, w, ev->events);
2192                 break;
2193
2194         default:
2195                 assert_not_reached("Unknown epoll event type.");
2196         }
2197
2198         return 0;
2199 }
2200
2201 int manager_loop(Manager *m) {
2202         int r;
2203
2204         RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
2205
2206         assert(m);
2207         m->exit_code = MANAGER_RUNNING;
2208
2209         /* Release the path cache */
2210         set_free_free(m->unit_path_cache);
2211         m->unit_path_cache = NULL;
2212
2213         manager_check_finished(m);
2214
2215         /* There might still be some zombies hanging around from
2216          * before we were exec()'ed. Leat's reap them */
2217         if ((r = manager_dispatch_sigchld(m)) < 0)
2218                 return r;
2219
2220         while (m->exit_code == MANAGER_RUNNING) {
2221                 struct epoll_event event;
2222                 int n;
2223
2224                 if (!ratelimit_test(&rl)) {
2225                         /* Yay, something is going seriously wrong, pause a little */
2226                         log_warning("Looping too fast. Throttling execution a little.");
2227                         sleep(1);
2228                 }
2229
2230                 if (manager_dispatch_load_queue(m) > 0)
2231                         continue;
2232
2233                 if (manager_dispatch_run_queue(m) > 0)
2234                         continue;
2235
2236                 if (bus_dispatch(m) > 0)
2237                         continue;
2238
2239                 if (manager_dispatch_cleanup_queue(m) > 0)
2240                         continue;
2241
2242                 if (manager_dispatch_gc_queue(m) > 0)
2243                         continue;
2244
2245                 if (manager_dispatch_dbus_queue(m) > 0)
2246                         continue;
2247
2248                 if (swap_dispatch_reload(m) > 0)
2249                         continue;
2250
2251                 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
2252
2253                         if (errno == EINTR)
2254                                 continue;
2255
2256                         return -errno;
2257                 }
2258
2259                 assert(n == 1);
2260
2261                 if ((r = process_event(m, &event)) < 0)
2262                         return r;
2263         }
2264
2265         return m->exit_code;
2266 }
2267
2268 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
2269         char *n;
2270         Unit *u;
2271
2272         assert(m);
2273         assert(s);
2274         assert(_u);
2275
2276         if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
2277                 return -EINVAL;
2278
2279         if (!(n = bus_path_unescape(s+31)))
2280                 return -ENOMEM;
2281
2282         u = manager_get_unit(m, n);
2283         free(n);
2284
2285         if (!u)
2286                 return -ENOENT;
2287
2288         *_u = u;
2289
2290         return 0;
2291 }
2292
2293 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
2294         Job *j;
2295         unsigned id;
2296         int r;
2297
2298         assert(m);
2299         assert(s);
2300         assert(_j);
2301
2302         if (!startswith(s, "/org/freedesktop/systemd1/job/"))
2303                 return -EINVAL;
2304
2305         if ((r = safe_atou(s + 30, &id)) < 0)
2306                 return r;
2307
2308         if (!(j = manager_get_job(m, id)))
2309                 return -ENOENT;
2310
2311         *_j = j;
2312
2313         return 0;
2314 }
2315
2316 void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success) {
2317
2318 #ifdef HAVE_AUDIT
2319         char *p;
2320
2321         if (m->audit_fd < 0)
2322                 return;
2323
2324         /* Don't generate audit events if the service was already
2325          * started and we're just deserializing */
2326         if (m->n_deserializing > 0)
2327                 return;
2328
2329         if (!(p = unit_name_to_prefix_and_instance(u->meta.id))) {
2330                 log_error("Failed to allocate unit name for audit message: %s", strerror(ENOMEM));
2331                 return;
2332         }
2333
2334         if (audit_log_user_comm_message(m->audit_fd, type, "", p, NULL, NULL, NULL, success) < 0)
2335                 log_error("Failed to send audit message: %m");
2336
2337         free(p);
2338 #endif
2339
2340 }
2341
2342 void manager_send_unit_plymouth(Manager *m, Unit *u) {
2343         int fd = -1;
2344         union sockaddr_union sa;
2345         int n = 0;
2346         char *message = NULL;
2347         ssize_t r;
2348
2349         /* Don't generate plymouth events if the service was already
2350          * started and we're just deserializing */
2351         if (m->n_deserializing > 0)
2352                 return;
2353
2354         if (m->running_as != MANAGER_SYSTEM)
2355                 return;
2356
2357         if (u->meta.type != UNIT_SERVICE &&
2358             u->meta.type != UNIT_MOUNT &&
2359             u->meta.type != UNIT_SWAP)
2360                 return;
2361
2362         /* We set SOCK_NONBLOCK here so that we rather drop the
2363          * message then wait for plymouth */
2364         if ((fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) {
2365                 log_error("socket() failed: %m");
2366                 return;
2367         }
2368
2369         zero(sa);
2370         sa.sa.sa_family = AF_UNIX;
2371         strncpy(sa.un.sun_path+1, "/ply-boot-protocol", sizeof(sa.un.sun_path)-1);
2372         if (connect(fd, &sa.sa, sizeof(sa.un)) < 0) {
2373
2374                 if (errno != EPIPE &&
2375                     errno != EAGAIN &&
2376                     errno != ENOENT &&
2377                     errno != ECONNREFUSED &&
2378                     errno != ECONNRESET &&
2379                     errno != ECONNABORTED)
2380                         log_error("connect() failed: %m");
2381
2382                 goto finish;
2383         }
2384
2385         if (asprintf(&message, "U\002%c%s%n", (int) (strlen(u->meta.id) + 1), u->meta.id, &n) < 0) {
2386                 log_error("Out of memory");
2387                 goto finish;
2388         }
2389
2390         errno = 0;
2391         if ((r = write(fd, message, n + 1)) != n + 1) {
2392
2393                 if (errno != EPIPE &&
2394                     errno != EAGAIN &&
2395                     errno != ENOENT &&
2396                     errno != ECONNREFUSED &&
2397                     errno != ECONNRESET &&
2398                     errno != ECONNABORTED)
2399                         log_error("Failed to write Plymouth message: %m");
2400
2401                 goto finish;
2402         }
2403
2404 finish:
2405         if (fd >= 0)
2406                 close_nointr_nofail(fd);
2407
2408         free(message);
2409 }
2410
2411 void manager_dispatch_bus_name_owner_changed(
2412                 Manager *m,
2413                 const char *name,
2414                 const char* old_owner,
2415                 const char *new_owner) {
2416
2417         Unit *u;
2418
2419         assert(m);
2420         assert(name);
2421
2422         if (!(u = hashmap_get(m->watch_bus, name)))
2423                 return;
2424
2425         UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
2426 }
2427
2428 void manager_dispatch_bus_query_pid_done(
2429                 Manager *m,
2430                 const char *name,
2431                 pid_t pid) {
2432
2433         Unit *u;
2434
2435         assert(m);
2436         assert(name);
2437         assert(pid >= 1);
2438
2439         if (!(u = hashmap_get(m->watch_bus, name)))
2440                 return;
2441
2442         UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
2443 }
2444
2445 int manager_open_serialization(Manager *m, FILE **_f) {
2446         char *path;
2447         mode_t saved_umask;
2448         int fd;
2449         FILE *f;
2450
2451         assert(_f);
2452
2453         if (m->running_as == MANAGER_SYSTEM) {
2454                 mkdir_p("/dev/.systemd", 0755);
2455
2456                 if (asprintf(&path, "/dev/.systemd/dump-%lu-XXXXXX", (unsigned long) getpid()) < 0)
2457                         return -ENOMEM;
2458         } else {
2459                 if (asprintf(&path, "/tmp/systemd-dump-%lu-XXXXXX", (unsigned long) getpid()) < 0)
2460                         return -ENOMEM;
2461         }
2462
2463         saved_umask = umask(0077);
2464         fd = mkostemp(path, O_RDWR|O_CLOEXEC);
2465         umask(saved_umask);
2466
2467         if (fd < 0) {
2468                 free(path);
2469                 return -errno;
2470         }
2471
2472         unlink(path);
2473
2474         log_debug("Serializing state to %s", path);
2475         free(path);
2476
2477         if (!(f = fdopen(fd, "w+")) < 0)
2478                 return -errno;
2479
2480         *_f = f;
2481
2482         return 0;
2483 }
2484
2485 int manager_serialize(Manager *m, FILE *f, FDSet *fds) {
2486         Iterator i;
2487         Unit *u;
2488         const char *t;
2489         int r;
2490
2491         assert(m);
2492         assert(f);
2493         assert(fds);
2494
2495         dual_timestamp_serialize(f, "startup-timestamp", &m->startup_timestamp);
2496         dual_timestamp_serialize(f, "finish-timestamp", &m->finish_timestamp);
2497
2498         fputc('\n', f);
2499
2500         HASHMAP_FOREACH_KEY(u, t, m->units, i) {
2501                 if (u->meta.id != t)
2502                         continue;
2503
2504                 if (!unit_can_serialize(u))
2505                         continue;
2506
2507                 /* Start marker */
2508                 fputs(u->meta.id, f);
2509                 fputc('\n', f);
2510
2511                 if ((r = unit_serialize(u, f, fds)) < 0)
2512                         return r;
2513         }
2514
2515         if (ferror(f))
2516                 return -EIO;
2517
2518         return 0;
2519 }
2520
2521 int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
2522         int r = 0;
2523
2524         assert(m);
2525         assert(f);
2526
2527         log_debug("Deserializing state...");
2528
2529         m->n_deserializing ++;
2530
2531         for (;;) {
2532                 char line[1024], *l;
2533
2534                 if (!fgets(line, sizeof(line), f)) {
2535                         if (feof(f))
2536                                 r = 0;
2537                         else
2538                                 r = -errno;
2539
2540                         goto finish;
2541                 }
2542
2543                 char_array_0(line);
2544                 l = strstrip(line);
2545
2546                 if (l[0] == 0)
2547                         break;
2548
2549                 if (startswith(l, "startup-timestamp="))
2550                         dual_timestamp_deserialize(l+18, &m->startup_timestamp);
2551                 else if (startswith(l, "finish-timestamp="))
2552                         dual_timestamp_deserialize(l+17, &m->finish_timestamp);
2553                 else
2554                         log_debug("Unknown serialization item '%s'", l);
2555         }
2556
2557         for (;;) {
2558                 Unit *u;
2559                 char name[UNIT_NAME_MAX+2];
2560
2561                 /* Start marker */
2562                 if (!fgets(name, sizeof(name), f)) {
2563                         if (feof(f))
2564                                 r = 0;
2565                         else
2566                                 r = -errno;
2567
2568                         goto finish;
2569                 }
2570
2571                 char_array_0(name);
2572
2573                 if ((r = manager_load_unit(m, strstrip(name), NULL, NULL, &u)) < 0)
2574                         goto finish;
2575
2576                 if ((r = unit_deserialize(u, f, fds)) < 0)
2577                         goto finish;
2578         }
2579
2580 finish:
2581         if (ferror(f)) {
2582                 r = -EIO;
2583                 goto finish;
2584         }
2585
2586         assert(m->n_deserializing > 0);
2587         m->n_deserializing --;
2588
2589         return r;
2590 }
2591
2592 int manager_reload(Manager *m) {
2593         int r, q;
2594         FILE *f;
2595         FDSet *fds;
2596
2597         assert(m);
2598
2599         if ((r = manager_open_serialization(m, &f)) < 0)
2600                 return r;
2601
2602         if (!(fds = fdset_new())) {
2603                 r = -ENOMEM;
2604                 goto finish;
2605         }
2606
2607         if ((r = manager_serialize(m, f, fds)) < 0)
2608                 goto finish;
2609
2610         if (fseeko(f, 0, SEEK_SET) < 0) {
2611                 r = -errno;
2612                 goto finish;
2613         }
2614
2615         /* From here on there is no way back. */
2616         manager_clear_jobs_and_units(m);
2617
2618         /* Find new unit paths */
2619         lookup_paths_free(&m->lookup_paths);
2620         if ((q = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
2621                 r = q;
2622
2623         m->n_deserializing ++;
2624
2625         /* First, enumerate what we can from all config files */
2626         if ((q = manager_enumerate(m)) < 0)
2627                 r = q;
2628
2629         /* Second, deserialize our stored data */
2630         if ((q = manager_deserialize(m, f, fds)) < 0)
2631                 r = q;
2632
2633         fclose(f);
2634         f = NULL;
2635
2636         /* Third, fire things up! */
2637         if ((q = manager_coldplug(m)) < 0)
2638                 r = q;
2639
2640         assert(m->n_deserializing > 0);
2641         m->n_deserializing ++;
2642
2643 finish:
2644         if (f)
2645                 fclose(f);
2646
2647         if (fds)
2648                 fdset_free(fds);
2649
2650         return r;
2651 }
2652
2653 bool manager_is_booting_or_shutting_down(Manager *m) {
2654         Unit *u;
2655
2656         assert(m);
2657
2658         /* Is the initial job still around? */
2659         if (manager_get_job(m, 1))
2660                 return true;
2661
2662         /* Is there a job for the shutdown target? */
2663         if (((u = manager_get_unit(m, SPECIAL_SHUTDOWN_TARGET))))
2664                 return !!u->meta.job;
2665
2666         return false;
2667 }
2668
2669 void manager_reset_failed(Manager *m) {
2670         Unit *u;
2671         Iterator i;
2672
2673         assert(m);
2674
2675         HASHMAP_FOREACH(u, m->units, i)
2676                 unit_reset_failed(u);
2677 }
2678
2679 int manager_set_console(Manager *m, const char *console) {
2680         char *c;
2681
2682         assert(m);
2683
2684         if (!(c = strdup(console)))
2685                 return -ENOMEM;
2686
2687         free(m->console);
2688         m->console = c;
2689
2690         log_debug("Using kernel console %s", c);
2691
2692         return 0;
2693 }
2694
2695 bool manager_unit_pending_inactive(Manager *m, const char *name) {
2696         Unit *u;
2697
2698         assert(m);
2699         assert(name);
2700
2701         /* Returns true if the unit is inactive or going down */
2702         if (!(u = manager_get_unit(m, name)))
2703                 return true;
2704
2705         return unit_pending_inactive(u);
2706 }
2707
2708 void manager_check_finished(Manager *m) {
2709         char userspace[FORMAT_TIMESPAN_MAX], kernel[FORMAT_TIMESPAN_MAX], sum[FORMAT_TIMESPAN_MAX];
2710
2711         assert(m);
2712
2713         if (dual_timestamp_is_set(&m->finish_timestamp))
2714                 return;
2715
2716         if (hashmap_size(m->jobs) > 0)
2717                 return;
2718
2719         dual_timestamp_get(&m->finish_timestamp);
2720
2721         if (m->running_as == MANAGER_SYSTEM)
2722                 log_info("Startup finished in %s (kernel) + %s (userspace) = %s.",
2723                          format_timespan(kernel, sizeof(kernel),
2724                                          m->startup_timestamp.monotonic),
2725                          format_timespan(userspace, sizeof(userspace),
2726                                          m->finish_timestamp.monotonic - m->startup_timestamp.monotonic),
2727                          format_timespan(sum, sizeof(sum),
2728                                          m->finish_timestamp.monotonic));
2729         else
2730                 log_debug("Startup finished in %s.",
2731                           format_timespan(userspace, sizeof(userspace),
2732                                           m->finish_timestamp.monotonic - m->startup_timestamp.monotonic));
2733
2734 }
2735
2736 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
2737         [MANAGER_SYSTEM] = "system",
2738         [MANAGER_SESSION] = "session"
2739 };
2740
2741 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);