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
1203         /* As last step, kill all remaining job dependencies. */
1204         transaction_clean_dependencies(m);
1205
1206         return 0;
1207
1208 rollback:
1209
1210         HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1211                 if (j->installed)
1212                         continue;
1213
1214                 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1215         }
1216
1217         return r;
1218 }
1219
1220 static int transaction_activate(Manager *m, JobMode mode, DBusError *e) {
1221         int r;
1222         unsigned generation = 1;
1223
1224         assert(m);
1225
1226         /* This applies the changes recorded in transaction_jobs to
1227          * the actual list of jobs, if possible. */
1228
1229         /* First step: figure out which jobs matter */
1230         transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1231
1232         /* Second step: Try not to stop any running services if
1233          * we don't have to. Don't try to reverse running
1234          * jobs if we don't have to. */
1235         if (mode != JOB_ISOLATE)
1236                 transaction_minimize_impact(m);
1237
1238         /* Third step: Drop redundant jobs */
1239         transaction_drop_redundant(m);
1240
1241         for (;;) {
1242                 /* Fourth step: Let's remove unneeded jobs that might
1243                  * be lurking. */
1244                 transaction_collect_garbage(m);
1245
1246                 /* Fifth step: verify order makes sense and correct
1247                  * cycles if necessary and possible */
1248                 if ((r = transaction_verify_order(m, &generation, e)) >= 0)
1249                         break;
1250
1251                 if (r != -EAGAIN) {
1252                         log_warning("Requested transaction contains an unfixable cyclic ordering dependency: %s", bus_error(e, r));
1253                         goto rollback;
1254                 }
1255
1256                 /* Let's see if the resulting transaction ordering
1257                  * graph is still cyclic... */
1258         }
1259
1260         for (;;) {
1261                 /* Sixth step: let's drop unmergeable entries if
1262                  * necessary and possible, merge entries we can
1263                  * merge */
1264                 if ((r = transaction_merge_jobs(m, e)) >= 0)
1265                         break;
1266
1267                 if (r != -EAGAIN) {
1268                         log_warning("Requested transaction contains unmergable jobs: %s", bus_error(e, r));
1269                         goto rollback;
1270                 }
1271
1272                 /* Seventh step: an entry got dropped, let's garbage
1273                  * collect its dependencies. */
1274                 transaction_collect_garbage(m);
1275
1276                 /* Let's see if the resulting transaction still has
1277                  * unmergeable entries ... */
1278         }
1279
1280         /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1281         transaction_drop_redundant(m);
1282
1283         /* Ninth step: check whether we can actually apply this */
1284         if (mode == JOB_FAIL)
1285                 if ((r = transaction_is_destructive(m, e)) < 0) {
1286                         log_notice("Requested transaction contradicts existing jobs: %s", bus_error(e, r));
1287                         goto rollback;
1288                 }
1289
1290         /* Tenth step: apply changes */
1291         if ((r = transaction_apply(m)) < 0) {
1292                 log_warning("Failed to apply transaction: %s", strerror(-r));
1293                 goto rollback;
1294         }
1295
1296         assert(hashmap_isempty(m->transaction_jobs));
1297         assert(!m->transaction_anchor);
1298
1299         return 0;
1300
1301 rollback:
1302         transaction_abort(m);
1303         return r;
1304 }
1305
1306 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1307         Job *j, *f;
1308
1309         assert(m);
1310         assert(unit);
1311
1312         /* Looks for an axisting prospective job and returns that. If
1313          * it doesn't exist it is created and added to the prospective
1314          * jobs list. */
1315
1316         f = hashmap_get(m->transaction_jobs, unit);
1317
1318         LIST_FOREACH(transaction, j, f) {
1319                 assert(j->unit == unit);
1320
1321                 if (j->type == type) {
1322                         if (is_new)
1323                                 *is_new = false;
1324                         return j;
1325                 }
1326         }
1327
1328         if (unit->meta.job && unit->meta.job->type == type)
1329                 j = unit->meta.job;
1330         else if (!(j = job_new(m, type, unit)))
1331                 return NULL;
1332
1333         j->generation = 0;
1334         j->marker = NULL;
1335         j->matters_to_anchor = false;
1336         j->override = override;
1337
1338         LIST_PREPEND(Job, transaction, f, j);
1339
1340         if (hashmap_replace(m->transaction_jobs, unit, f) < 0) {
1341                 job_free(j);
1342                 return NULL;
1343         }
1344
1345         if (is_new)
1346                 *is_new = true;
1347
1348         log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1349
1350         return j;
1351 }
1352
1353 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1354         assert(m);
1355         assert(j);
1356
1357         if (j->transaction_prev)
1358                 j->transaction_prev->transaction_next = j->transaction_next;
1359         else if (j->transaction_next)
1360                 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1361         else
1362                 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1363
1364         if (j->transaction_next)
1365                 j->transaction_next->transaction_prev = j->transaction_prev;
1366
1367         j->transaction_prev = j->transaction_next = NULL;
1368
1369         while (j->subject_list)
1370                 job_dependency_free(j->subject_list);
1371
1372         while (j->object_list) {
1373                 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1374
1375                 job_dependency_free(j->object_list);
1376
1377                 if (other && delete_dependencies) {
1378                         log_debug("Deleting job %s/%s as dependency of job %s/%s",
1379                                   other->unit->meta.id, job_type_to_string(other->type),
1380                                   j->unit->meta.id, job_type_to_string(j->type));
1381                         transaction_delete_job(m, other, delete_dependencies);
1382                 }
1383         }
1384 }
1385
1386 static int transaction_add_job_and_dependencies(
1387                 Manager *m,
1388                 JobType type,
1389                 Unit *unit,
1390                 Job *by,
1391                 bool matters,
1392                 bool override,
1393                 bool conflicts,
1394                 DBusError *e,
1395                 Job **_ret) {
1396         Job *ret;
1397         Iterator i;
1398         Unit *dep;
1399         int r;
1400         bool is_new;
1401
1402         assert(m);
1403         assert(type < _JOB_TYPE_MAX);
1404         assert(unit);
1405
1406         if (unit->meta.load_state != UNIT_LOADED &&
1407             unit->meta.load_state != UNIT_ERROR &&
1408             unit->meta.load_state != UNIT_MASKED) {
1409                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED, "Unit %s is not loaded properly.", unit->meta.id);
1410                 return -EINVAL;
1411         }
1412
1413         if (type != JOB_STOP && unit->meta.load_state == UNIT_ERROR) {
1414                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED,
1415                                "Unit %s failed to load: %s. "
1416                                "See system logs and 'systemctl status' for details.",
1417                                unit->meta.id,
1418                                strerror(-unit->meta.load_error));
1419                 return -EINVAL;
1420         }
1421
1422         if (type != JOB_STOP && unit->meta.load_state == UNIT_MASKED) {
1423                 dbus_set_error(e, BUS_ERROR_MASKED, "Unit %s is masked.", unit->meta.id);
1424                 return -EINVAL;
1425         }
1426
1427         if (!unit_job_is_applicable(unit, type)) {
1428                 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);
1429                 return -EBADR;
1430         }
1431
1432         /* First add the job. */
1433         if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1434                 return -ENOMEM;
1435
1436         /* Then, add a link to the job. */
1437         if (!job_dependency_new(by, ret, matters, conflicts))
1438                 return -ENOMEM;
1439
1440         if (is_new) {
1441                 /* Finally, recursively add in all dependencies. */
1442                 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1443                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1444                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1445                                         goto fail;
1446
1447                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1448                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, false, e, NULL)) < 0 && r != -EBADR) {
1449                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1450
1451                                         if (e)
1452                                                 dbus_error_free(e);
1453                                 }
1454
1455                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1456                                 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, false, e, NULL)) < 0) {
1457                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1458
1459                                         if (e)
1460                                                 dbus_error_free(e);
1461                                 }
1462
1463                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1464                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1465                                         goto fail;
1466
1467                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1468                                 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, false, e, NULL)) < 0 && r != -EBADR) {
1469                                         log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r));
1470
1471                                         if (e)
1472                                                 dbus_error_free(e);
1473                                 }
1474
1475                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1476                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, true, e, NULL)) < 0 && r != -EBADR)
1477                                         goto fail;
1478
1479                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTED_BY], i)
1480                                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1481                                         goto fail;
1482
1483                 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1484
1485                         SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1486                                 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, false, e, NULL)) < 0 && r != -EBADR)
1487                                         goto fail;
1488                 }
1489
1490                 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1491         }
1492
1493         if (_ret)
1494                 *_ret = ret;
1495
1496         return 0;
1497
1498 fail:
1499         return r;
1500 }
1501
1502 static int transaction_add_isolate_jobs(Manager *m) {
1503         Iterator i;
1504         Unit *u;
1505         char *k;
1506         int r;
1507
1508         assert(m);
1509
1510         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
1511
1512                 /* ignore aliases */
1513                 if (u->meta.id != k)
1514                         continue;
1515
1516                 if (UNIT_VTABLE(u)->no_isolate)
1517                         continue;
1518
1519                 /* No need to stop inactive jobs */
1520                 if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(u)))
1521                         continue;
1522
1523                 /* Is there already something listed for this? */
1524                 if (hashmap_get(m->transaction_jobs, u))
1525                         continue;
1526
1527                 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, u, NULL, true, false, false, NULL, NULL)) < 0)
1528                         log_warning("Cannot add isolate job for unit %s, ignoring: %s", u->meta.id, strerror(-r));
1529         }
1530
1531         return 0;
1532 }
1533
1534 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, DBusError *e, Job **_ret) {
1535         int r;
1536         Job *ret;
1537
1538         assert(m);
1539         assert(type < _JOB_TYPE_MAX);
1540         assert(unit);
1541         assert(mode < _JOB_MODE_MAX);
1542
1543         if (mode == JOB_ISOLATE && type != JOB_START) {
1544                 dbus_set_error(e, BUS_ERROR_INVALID_JOB_MODE, "Isolate is only valid for start.");
1545                 return -EINVAL;
1546         }
1547
1548         if (mode == JOB_ISOLATE && !unit->meta.allow_isolate) {
1549                 dbus_set_error(e, BUS_ERROR_NO_ISOLATION, "Operation refused, unit may not be isolated.");
1550                 return -EPERM;
1551         }
1552
1553         log_debug("Trying to enqueue job %s/%s/%s", unit->meta.id, job_type_to_string(type), job_mode_to_string(mode));
1554
1555         if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, false, e, &ret)) < 0) {
1556                 transaction_abort(m);
1557                 return r;
1558         }
1559
1560         if (mode == JOB_ISOLATE)
1561                 if ((r = transaction_add_isolate_jobs(m)) < 0) {
1562                         transaction_abort(m);
1563                         return r;
1564                 }
1565
1566         if ((r = transaction_activate(m, mode, e)) < 0)
1567                 return r;
1568
1569         log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id);
1570
1571         if (_ret)
1572                 *_ret = ret;
1573
1574         return 0;
1575 }
1576
1577 int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, DBusError *e, Job **_ret) {
1578         Unit *unit;
1579         int r;
1580
1581         assert(m);
1582         assert(type < _JOB_TYPE_MAX);
1583         assert(name);
1584         assert(mode < _JOB_MODE_MAX);
1585
1586         if ((r = manager_load_unit(m, name, NULL, NULL, &unit)) < 0)
1587                 return r;
1588
1589         return manager_add_job(m, type, unit, mode, override, e, _ret);
1590 }
1591
1592 Job *manager_get_job(Manager *m, uint32_t id) {
1593         assert(m);
1594
1595         return hashmap_get(m->jobs, UINT32_TO_PTR(id));
1596 }
1597
1598 Unit *manager_get_unit(Manager *m, const char *name) {
1599         assert(m);
1600         assert(name);
1601
1602         return hashmap_get(m->units, name);
1603 }
1604
1605 unsigned manager_dispatch_load_queue(Manager *m) {
1606         Meta *meta;
1607         unsigned n = 0;
1608
1609         assert(m);
1610
1611         /* Make sure we are not run recursively */
1612         if (m->dispatching_load_queue)
1613                 return 0;
1614
1615         m->dispatching_load_queue = true;
1616
1617         /* Dispatches the load queue. Takes a unit from the queue and
1618          * tries to load its data until the queue is empty */
1619
1620         while ((meta = m->load_queue)) {
1621                 assert(meta->in_load_queue);
1622
1623                 unit_load((Unit*) meta);
1624                 n++;
1625         }
1626
1627         m->dispatching_load_queue = false;
1628         return n;
1629 }
1630
1631 int manager_load_unit_prepare(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1632         Unit *ret;
1633         int r;
1634
1635         assert(m);
1636         assert(name || path);
1637
1638         /* This will prepare the unit for loading, but not actually
1639          * load anything from disk. */
1640
1641         if (path && !is_path(path)) {
1642                 dbus_set_error(e, BUS_ERROR_INVALID_PATH, "Path %s is not absolute.", path);
1643                 return -EINVAL;
1644         }
1645
1646         if (!name)
1647                 name = file_name_from_path(path);
1648
1649         if (!unit_name_is_valid(name, false)) {
1650                 dbus_set_error(e, BUS_ERROR_INVALID_NAME, "Unit name %s is not valid.", name);
1651                 return -EINVAL;
1652         }
1653
1654         if ((ret = manager_get_unit(m, name))) {
1655                 *_ret = ret;
1656                 return 1;
1657         }
1658
1659         if (!(ret = unit_new(m)))
1660                 return -ENOMEM;
1661
1662         if (path)
1663                 if (!(ret->meta.fragment_path = strdup(path))) {
1664                         unit_free(ret);
1665                         return -ENOMEM;
1666                 }
1667
1668         if ((r = unit_add_name(ret, name)) < 0) {
1669                 unit_free(ret);
1670                 return r;
1671         }
1672
1673         unit_add_to_load_queue(ret);
1674         unit_add_to_dbus_queue(ret);
1675         unit_add_to_gc_queue(ret);
1676
1677         if (_ret)
1678                 *_ret = ret;
1679
1680         return 0;
1681 }
1682
1683 int manager_load_unit(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) {
1684         int r;
1685
1686         assert(m);
1687
1688         /* This will load the service information files, but not actually
1689          * start any services or anything. */
1690
1691         if ((r = manager_load_unit_prepare(m, name, path, e, _ret)) != 0)
1692                 return r;
1693
1694         manager_dispatch_load_queue(m);
1695
1696         if (_ret)
1697                 *_ret = unit_follow_merge(*_ret);
1698
1699         return 0;
1700 }
1701
1702 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1703         Iterator i;
1704         Job *j;
1705
1706         assert(s);
1707         assert(f);
1708
1709         HASHMAP_FOREACH(j, s->jobs, i)
1710                 job_dump(j, f, prefix);
1711 }
1712
1713 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1714         Iterator i;
1715         Unit *u;
1716         const char *t;
1717
1718         assert(s);
1719         assert(f);
1720
1721         HASHMAP_FOREACH_KEY(u, t, s->units, i)
1722                 if (u->meta.id == t)
1723                         unit_dump(u, f, prefix);
1724 }
1725
1726 void manager_clear_jobs(Manager *m) {
1727         Job *j;
1728
1729         assert(m);
1730
1731         transaction_abort(m);
1732
1733         while ((j = hashmap_first(m->jobs)))
1734                 job_free(j);
1735 }
1736
1737 unsigned manager_dispatch_run_queue(Manager *m) {
1738         Job *j;
1739         unsigned n = 0;
1740
1741         if (m->dispatching_run_queue)
1742                 return 0;
1743
1744         m->dispatching_run_queue = true;
1745
1746         while ((j = m->run_queue)) {
1747                 assert(j->installed);
1748                 assert(j->in_run_queue);
1749
1750                 job_run_and_invalidate(j);
1751                 n++;
1752         }
1753
1754         m->dispatching_run_queue = false;
1755         return n;
1756 }
1757
1758 unsigned manager_dispatch_dbus_queue(Manager *m) {
1759         Job *j;
1760         Meta *meta;
1761         unsigned n = 0;
1762
1763         assert(m);
1764
1765         if (m->dispatching_dbus_queue)
1766                 return 0;
1767
1768         m->dispatching_dbus_queue = true;
1769
1770         while ((meta = m->dbus_unit_queue)) {
1771                 assert(meta->in_dbus_queue);
1772
1773                 bus_unit_send_change_signal((Unit*) meta);
1774                 n++;
1775         }
1776
1777         while ((j = m->dbus_job_queue)) {
1778                 assert(j->in_dbus_queue);
1779
1780                 bus_job_send_change_signal(j);
1781                 n++;
1782         }
1783
1784         m->dispatching_dbus_queue = false;
1785         return n;
1786 }
1787
1788 static int manager_process_notify_fd(Manager *m) {
1789         ssize_t n;
1790
1791         assert(m);
1792
1793         for (;;) {
1794                 char buf[4096];
1795                 struct msghdr msghdr;
1796                 struct iovec iovec;
1797                 struct ucred *ucred;
1798                 union {
1799                         struct cmsghdr cmsghdr;
1800                         uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
1801                 } control;
1802                 Unit *u;
1803                 char **tags;
1804
1805                 zero(iovec);
1806                 iovec.iov_base = buf;
1807                 iovec.iov_len = sizeof(buf)-1;
1808
1809                 zero(control);
1810                 zero(msghdr);
1811                 msghdr.msg_iov = &iovec;
1812                 msghdr.msg_iovlen = 1;
1813                 msghdr.msg_control = &control;
1814                 msghdr.msg_controllen = sizeof(control);
1815
1816                 if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) <= 0) {
1817                         if (n >= 0)
1818                                 return -EIO;
1819
1820                         if (errno == EAGAIN || errno == EINTR)
1821                                 break;
1822
1823                         return -errno;
1824                 }
1825
1826                 if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
1827                     control.cmsghdr.cmsg_level != SOL_SOCKET ||
1828                     control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
1829                     control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
1830                         log_warning("Received notify message without credentials. Ignoring.");
1831                         continue;
1832                 }
1833
1834                 ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
1835
1836                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(ucred->pid))))
1837                         if (!(u = cgroup_unit_by_pid(m, ucred->pid))) {
1838                                 log_warning("Cannot find unit for notify message of PID %lu.", (unsigned long) ucred->pid);
1839                                 continue;
1840                         }
1841
1842                 assert((size_t) n < sizeof(buf));
1843                 buf[n] = 0;
1844                 if (!(tags = strv_split(buf, "\n\r")))
1845                         return -ENOMEM;
1846
1847                 log_debug("Got notification message for unit %s", u->meta.id);
1848
1849                 if (UNIT_VTABLE(u)->notify_message)
1850                         UNIT_VTABLE(u)->notify_message(u, ucred->pid, tags);
1851
1852                 strv_free(tags);
1853         }
1854
1855         return 0;
1856 }
1857
1858 static int manager_dispatch_sigchld(Manager *m) {
1859         assert(m);
1860
1861         for (;;) {
1862                 siginfo_t si;
1863                 Unit *u;
1864                 int r;
1865
1866                 zero(si);
1867
1868                 /* First we call waitd() for a PID and do not reap the
1869                  * zombie. That way we can still access /proc/$PID for
1870                  * it while it is a zombie. */
1871                 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1872
1873                         if (errno == ECHILD)
1874                                 break;
1875
1876                         if (errno == EINTR)
1877                                 continue;
1878
1879                         return -errno;
1880                 }
1881
1882                 if (si.si_pid <= 0)
1883                         break;
1884
1885                 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1886                         char *name = NULL;
1887
1888                         get_process_name(si.si_pid, &name);
1889                         log_debug("Got SIGCHLD for process %lu (%s)", (unsigned long) si.si_pid, strna(name));
1890                         free(name);
1891                 }
1892
1893                 /* Let's flush any message the dying child might still
1894                  * have queued for us. This ensures that the process
1895                  * still exists in /proc so that we can figure out
1896                  * which cgroup and hence unit it belongs to. */
1897                 if ((r = manager_process_notify_fd(m)) < 0)
1898                         return r;
1899
1900                 /* And now figure out the unit this belongs to */
1901                 if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(si.si_pid))))
1902                         u = cgroup_unit_by_pid(m, si.si_pid);
1903
1904                 /* And now, we actually reap the zombie. */
1905                 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1906                         if (errno == EINTR)
1907                                 continue;
1908
1909                         return -errno;
1910                 }
1911
1912                 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1913                         continue;
1914
1915                 log_debug("Child %lu died (code=%s, status=%i/%s)",
1916                           (long unsigned) si.si_pid,
1917                           sigchld_code_to_string(si.si_code),
1918                           si.si_status,
1919                           strna(si.si_code == CLD_EXITED
1920                                 ? exit_status_to_string(si.si_status, EXIT_STATUS_FULL)
1921                                 : signal_to_string(si.si_status)));
1922
1923                 if (!u)
1924                         continue;
1925
1926                 log_debug("Child %lu belongs to %s", (long unsigned) si.si_pid, u->meta.id);
1927
1928                 hashmap_remove(m->watch_pids, LONG_TO_PTR(si.si_pid));
1929                 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1930         }
1931
1932         return 0;
1933 }
1934
1935 static int manager_start_target(Manager *m, const char *name, JobMode mode) {
1936         int r;
1937         DBusError error;
1938
1939         dbus_error_init(&error);
1940
1941         log_info("Activating special unit %s", name);
1942
1943         if ((r = manager_add_job_by_name(m, JOB_START, name, mode, true, &error, NULL)) < 0)
1944                 log_error("Failed to enqueue %s job: %s", name, bus_error(&error, r));
1945
1946         dbus_error_free(&error);
1947
1948         return r;
1949 }
1950
1951 static int manager_process_signal_fd(Manager *m) {
1952         ssize_t n;
1953         struct signalfd_siginfo sfsi;
1954         bool sigchld = false;
1955
1956         assert(m);
1957
1958         for (;;) {
1959                 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1960
1961                         if (n >= 0)
1962                                 return -EIO;
1963
1964                         if (errno == EINTR || errno == EAGAIN)
1965                                 break;
1966
1967                         return -errno;
1968                 }
1969
1970                 log_debug("Received SIG%s", strna(signal_to_string(sfsi.ssi_signo)));
1971
1972                 switch (sfsi.ssi_signo) {
1973
1974                 case SIGCHLD:
1975                         sigchld = true;
1976                         break;
1977
1978                 case SIGTERM:
1979                         if (m->running_as == MANAGER_SYSTEM) {
1980                                 /* This is for compatibility with the
1981                                  * original sysvinit */
1982                                 m->exit_code = MANAGER_REEXECUTE;
1983                                 break;
1984                         }
1985
1986                         /* Fall through */
1987
1988                 case SIGINT:
1989                         if (m->running_as == MANAGER_SYSTEM) {
1990                                 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET, JOB_REPLACE);
1991                                 break;
1992                         }
1993
1994                         /* Run the exit target if there is one, if not, just exit. */
1995                         if (manager_start_target(m, SPECIAL_EXIT_TARGET, JOB_REPLACE) < 0) {
1996                                 m->exit_code = MANAGER_EXIT;
1997                                 return 0;
1998                         }
1999
2000                         break;
2001
2002                 case SIGWINCH:
2003                         if (m->running_as == MANAGER_SYSTEM)
2004                                 manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE);
2005
2006                         /* This is a nop on non-init */
2007                         break;
2008
2009                 case SIGPWR:
2010                         if (m->running_as == MANAGER_SYSTEM)
2011                                 manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE);
2012
2013                         /* This is a nop on non-init */
2014                         break;
2015
2016                 case SIGUSR1: {
2017                         Unit *u;
2018
2019                         u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
2020
2021                         if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
2022                                 log_info("Trying to reconnect to bus...");
2023                                 bus_init(m);
2024                         }
2025
2026                         if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
2027                                 log_info("Loading D-Bus service...");
2028                                 manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE);
2029                         }
2030
2031                         break;
2032                 }
2033
2034                 case SIGUSR2: {
2035                         FILE *f;
2036                         char *dump = NULL;
2037                         size_t size;
2038
2039                         if (!(f = open_memstream(&dump, &size))) {
2040                                 log_warning("Failed to allocate memory stream.");
2041                                 break;
2042                         }
2043
2044                         manager_dump_units(m, f, "\t");
2045                         manager_dump_jobs(m, f, "\t");
2046
2047                         if (ferror(f)) {
2048                                 fclose(f);
2049                                 free(dump);
2050                                 log_warning("Failed to write status stream");
2051                                 break;
2052                         }
2053
2054                         fclose(f);
2055                         log_dump(LOG_INFO, dump);
2056                         free(dump);
2057
2058                         break;
2059                 }
2060
2061                 case SIGHUP:
2062                         m->exit_code = MANAGER_RELOAD;
2063                         break;
2064
2065                 default: {
2066                         /* Starting SIGRTMIN+0 */
2067                         static const char * const target_table[] = {
2068                                 [0] = SPECIAL_DEFAULT_TARGET,
2069                                 [1] = SPECIAL_RESCUE_TARGET,
2070                                 [2] = SPECIAL_EMERGENCY_TARGET,
2071                                 [3] = SPECIAL_HALT_TARGET,
2072                                 [4] = SPECIAL_POWEROFF_TARGET,
2073                                 [5] = SPECIAL_REBOOT_TARGET,
2074                                 [6] = SPECIAL_KEXEC_TARGET
2075                         };
2076
2077                         /* Starting SIGRTMIN+13, so that target halt and system halt are 10 apart */
2078                         static const ManagerExitCode code_table[] = {
2079                                 [0] = MANAGER_HALT,
2080                                 [1] = MANAGER_POWEROFF,
2081                                 [2] = MANAGER_REBOOT,
2082                                 [3] = MANAGER_KEXEC
2083                         };
2084
2085                         if ((int) sfsi.ssi_signo >= SIGRTMIN+0 &&
2086                             (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(target_table)) {
2087                                 manager_start_target(m, target_table[sfsi.ssi_signo - SIGRTMIN],
2088                                                      (sfsi.ssi_signo == 1 || sfsi.ssi_signo == 2) ? JOB_ISOLATE : JOB_REPLACE);
2089                                 break;
2090                         }
2091
2092                         if ((int) sfsi.ssi_signo >= SIGRTMIN+13 &&
2093                             (int) sfsi.ssi_signo < SIGRTMIN+13+(int) ELEMENTSOF(code_table)) {
2094                                 m->exit_code = code_table[sfsi.ssi_signo - SIGRTMIN - 13];
2095                                 break;
2096                         }
2097
2098                         log_warning("Got unhandled signal <%s>.", strna(signal_to_string(sfsi.ssi_signo)));
2099                 }
2100                 }
2101         }
2102
2103         if (sigchld)
2104                 return manager_dispatch_sigchld(m);
2105
2106         return 0;
2107 }
2108
2109 static int process_event(Manager *m, struct epoll_event *ev) {
2110         int r;
2111         Watch *w;
2112
2113         assert(m);
2114         assert(ev);
2115
2116         assert(w = ev->data.ptr);
2117
2118         switch (w->type) {
2119
2120         case WATCH_SIGNAL:
2121
2122                 /* An incoming signal? */
2123                 if (ev->events != EPOLLIN)
2124                         return -EINVAL;
2125
2126                 if ((r = manager_process_signal_fd(m)) < 0)
2127                         return r;
2128
2129                 break;
2130
2131         case WATCH_NOTIFY:
2132
2133                 /* An incoming daemon notification event? */
2134                 if (ev->events != EPOLLIN)
2135                         return -EINVAL;
2136
2137                 if ((r = manager_process_notify_fd(m)) < 0)
2138                         return r;
2139
2140                 break;
2141
2142         case WATCH_FD:
2143
2144                 /* Some fd event, to be dispatched to the units */
2145                 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
2146                 break;
2147
2148         case WATCH_UNIT_TIMER:
2149         case WATCH_JOB_TIMER: {
2150                 uint64_t v;
2151                 ssize_t k;
2152
2153                 /* Some timer event, to be dispatched to the units */
2154                 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
2155
2156                         if (k < 0 && (errno == EINTR || errno == EAGAIN))
2157                                 break;
2158
2159                         return k < 0 ? -errno : -EIO;
2160                 }
2161
2162                 if (w->type == WATCH_UNIT_TIMER)
2163                         UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
2164                 else
2165                         job_timer_event(w->data.job, v, w);
2166                 break;
2167         }
2168
2169         case WATCH_MOUNT:
2170                 /* Some mount table change, intended for the mount subsystem */
2171                 mount_fd_event(m, ev->events);
2172                 break;
2173
2174         case WATCH_SWAP:
2175                 /* Some swap table change, intended for the swap subsystem */
2176                 swap_fd_event(m, ev->events);
2177                 break;
2178
2179         case WATCH_UDEV:
2180                 /* Some notification from udev, intended for the device subsystem */
2181                 device_fd_event(m, ev->events);
2182                 break;
2183
2184         case WATCH_DBUS_WATCH:
2185                 bus_watch_event(m, w, ev->events);
2186                 break;
2187
2188         case WATCH_DBUS_TIMEOUT:
2189                 bus_timeout_event(m, w, ev->events);
2190                 break;
2191
2192         default:
2193                 assert_not_reached("Unknown epoll event type.");
2194         }
2195
2196         return 0;
2197 }
2198
2199 int manager_loop(Manager *m) {
2200         int r;
2201
2202         RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
2203
2204         assert(m);
2205         m->exit_code = MANAGER_RUNNING;
2206
2207         /* Release the path cache */
2208         set_free_free(m->unit_path_cache);
2209         m->unit_path_cache = NULL;
2210
2211         manager_check_finished(m);
2212
2213         /* There might still be some zombies hanging around from
2214          * before we were exec()'ed. Leat's reap them */
2215         if ((r = manager_dispatch_sigchld(m)) < 0)
2216                 return r;
2217
2218         while (m->exit_code == MANAGER_RUNNING) {
2219                 struct epoll_event event;
2220                 int n;
2221
2222                 if (!ratelimit_test(&rl)) {
2223                         /* Yay, something is going seriously wrong, pause a little */
2224                         log_warning("Looping too fast. Throttling execution a little.");
2225                         sleep(1);
2226                 }
2227
2228                 if (manager_dispatch_load_queue(m) > 0)
2229                         continue;
2230
2231                 if (manager_dispatch_run_queue(m) > 0)
2232                         continue;
2233
2234                 if (bus_dispatch(m) > 0)
2235                         continue;
2236
2237                 if (manager_dispatch_cleanup_queue(m) > 0)
2238                         continue;
2239
2240                 if (manager_dispatch_gc_queue(m) > 0)
2241                         continue;
2242
2243                 if (manager_dispatch_dbus_queue(m) > 0)
2244                         continue;
2245
2246                 if (swap_dispatch_reload(m) > 0)
2247                         continue;
2248
2249                 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
2250
2251                         if (errno == EINTR)
2252                                 continue;
2253
2254                         return -errno;
2255                 }
2256
2257                 assert(n == 1);
2258
2259                 if ((r = process_event(m, &event)) < 0)
2260                         return r;
2261         }
2262
2263         return m->exit_code;
2264 }
2265
2266 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
2267         char *n;
2268         Unit *u;
2269
2270         assert(m);
2271         assert(s);
2272         assert(_u);
2273
2274         if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
2275                 return -EINVAL;
2276
2277         if (!(n = bus_path_unescape(s+31)))
2278                 return -ENOMEM;
2279
2280         u = manager_get_unit(m, n);
2281         free(n);
2282
2283         if (!u)
2284                 return -ENOENT;
2285
2286         *_u = u;
2287
2288         return 0;
2289 }
2290
2291 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
2292         Job *j;
2293         unsigned id;
2294         int r;
2295
2296         assert(m);
2297         assert(s);
2298         assert(_j);
2299
2300         if (!startswith(s, "/org/freedesktop/systemd1/job/"))
2301                 return -EINVAL;
2302
2303         if ((r = safe_atou(s + 30, &id)) < 0)
2304                 return r;
2305
2306         if (!(j = manager_get_job(m, id)))
2307                 return -ENOENT;
2308
2309         *_j = j;
2310
2311         return 0;
2312 }
2313
2314 void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success) {
2315
2316 #ifdef HAVE_AUDIT
2317         char *p;
2318
2319         if (m->audit_fd < 0)
2320                 return;
2321
2322         /* Don't generate audit events if the service was already
2323          * started and we're just deserializing */
2324         if (m->n_deserializing > 0)
2325                 return;
2326
2327         if (!(p = unit_name_to_prefix_and_instance(u->meta.id))) {
2328                 log_error("Failed to allocate unit name for audit message: %s", strerror(ENOMEM));
2329                 return;
2330         }
2331
2332         if (audit_log_user_comm_message(m->audit_fd, type, "", p, NULL, NULL, NULL, success) < 0)
2333                 log_error("Failed to send audit message: %m");
2334
2335         free(p);
2336 #endif
2337
2338 }
2339
2340 void manager_send_unit_plymouth(Manager *m, Unit *u) {
2341         int fd = -1;
2342         union sockaddr_union sa;
2343         int n = 0;
2344         char *message = NULL;
2345         ssize_t r;
2346
2347         /* Don't generate plymouth events if the service was already
2348          * started and we're just deserializing */
2349         if (m->n_deserializing > 0)
2350                 return;
2351
2352         if (m->running_as != MANAGER_SYSTEM)
2353                 return;
2354
2355         if (u->meta.type != UNIT_SERVICE &&
2356             u->meta.type != UNIT_MOUNT &&
2357             u->meta.type != UNIT_SWAP)
2358                 return;
2359
2360         /* We set SOCK_NONBLOCK here so that we rather drop the
2361          * message then wait for plymouth */
2362         if ((fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) {
2363                 log_error("socket() failed: %m");
2364                 return;
2365         }
2366
2367         zero(sa);
2368         sa.sa.sa_family = AF_UNIX;
2369         strncpy(sa.un.sun_path+1, "/ply-boot-protocol", sizeof(sa.un.sun_path)-1);
2370         if (connect(fd, &sa.sa, sizeof(sa.un)) < 0) {
2371
2372                 if (errno != EPIPE &&
2373                     errno != EAGAIN &&
2374                     errno != ENOENT &&
2375                     errno != ECONNREFUSED &&
2376                     errno != ECONNRESET &&
2377                     errno != ECONNABORTED)
2378                         log_error("connect() failed: %m");
2379
2380                 goto finish;
2381         }
2382
2383         if (asprintf(&message, "U\002%c%s%n", (int) (strlen(u->meta.id) + 1), u->meta.id, &n) < 0) {
2384                 log_error("Out of memory");
2385                 goto finish;
2386         }
2387
2388         errno = 0;
2389         if ((r = write(fd, message, n + 1)) != n + 1) {
2390
2391                 if (errno != EPIPE &&
2392                     errno != EAGAIN &&
2393                     errno != ENOENT &&
2394                     errno != ECONNREFUSED &&
2395                     errno != ECONNRESET &&
2396                     errno != ECONNABORTED)
2397                         log_error("Failed to write Plymouth message: %m");
2398
2399                 goto finish;
2400         }
2401
2402 finish:
2403         if (fd >= 0)
2404                 close_nointr_nofail(fd);
2405
2406         free(message);
2407 }
2408
2409 void manager_dispatch_bus_name_owner_changed(
2410                 Manager *m,
2411                 const char *name,
2412                 const char* old_owner,
2413                 const char *new_owner) {
2414
2415         Unit *u;
2416
2417         assert(m);
2418         assert(name);
2419
2420         if (!(u = hashmap_get(m->watch_bus, name)))
2421                 return;
2422
2423         UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
2424 }
2425
2426 void manager_dispatch_bus_query_pid_done(
2427                 Manager *m,
2428                 const char *name,
2429                 pid_t pid) {
2430
2431         Unit *u;
2432
2433         assert(m);
2434         assert(name);
2435         assert(pid >= 1);
2436
2437         if (!(u = hashmap_get(m->watch_bus, name)))
2438                 return;
2439
2440         UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
2441 }
2442
2443 int manager_open_serialization(Manager *m, FILE **_f) {
2444         char *path;
2445         mode_t saved_umask;
2446         int fd;
2447         FILE *f;
2448
2449         assert(_f);
2450
2451         if (m->running_as == MANAGER_SYSTEM) {
2452                 mkdir_p("/dev/.systemd", 0755);
2453
2454                 if (asprintf(&path, "/dev/.systemd/dump-%lu-XXXXXX", (unsigned long) getpid()) < 0)
2455                         return -ENOMEM;
2456         } else {
2457                 if (asprintf(&path, "/tmp/systemd-dump-%lu-XXXXXX", (unsigned long) getpid()) < 0)
2458                         return -ENOMEM;
2459         }
2460
2461         saved_umask = umask(0077);
2462         fd = mkostemp(path, O_RDWR|O_CLOEXEC);
2463         umask(saved_umask);
2464
2465         if (fd < 0) {
2466                 free(path);
2467                 return -errno;
2468         }
2469
2470         unlink(path);
2471
2472         log_debug("Serializing state to %s", path);
2473         free(path);
2474
2475         if (!(f = fdopen(fd, "w+")) < 0)
2476                 return -errno;
2477
2478         *_f = f;
2479
2480         return 0;
2481 }
2482
2483 int manager_serialize(Manager *m, FILE *f, FDSet *fds) {
2484         Iterator i;
2485         Unit *u;
2486         const char *t;
2487         int r;
2488
2489         assert(m);
2490         assert(f);
2491         assert(fds);
2492
2493         dual_timestamp_serialize(f, "startup-timestamp", &m->startup_timestamp);
2494         dual_timestamp_serialize(f, "finish-timestamp", &m->finish_timestamp);
2495
2496         fputc('\n', f);
2497
2498         HASHMAP_FOREACH_KEY(u, t, m->units, i) {
2499                 if (u->meta.id != t)
2500                         continue;
2501
2502                 if (!unit_can_serialize(u))
2503                         continue;
2504
2505                 /* Start marker */
2506                 fputs(u->meta.id, f);
2507                 fputc('\n', f);
2508
2509                 if ((r = unit_serialize(u, f, fds)) < 0)
2510                         return r;
2511         }
2512
2513         if (ferror(f))
2514                 return -EIO;
2515
2516         return 0;
2517 }
2518
2519 int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
2520         int r = 0;
2521
2522         assert(m);
2523         assert(f);
2524
2525         log_debug("Deserializing state...");
2526
2527         m->n_deserializing ++;
2528
2529         for (;;) {
2530                 char line[1024], *l;
2531
2532                 if (!fgets(line, sizeof(line), f)) {
2533                         if (feof(f))
2534                                 r = 0;
2535                         else
2536                                 r = -errno;
2537
2538                         goto finish;
2539                 }
2540
2541                 char_array_0(line);
2542                 l = strstrip(line);
2543
2544                 if (l[0] == 0)
2545                         break;
2546
2547                 if (startswith(l, "startup-timestamp="))
2548                         dual_timestamp_deserialize(f, l+18, &m->startup_timestamp);
2549                 else if (startswith(l, "finish-timestamp="))
2550                         dual_timestamp_deserialize(f, l+17, &m->finish_timestamp);
2551                 else
2552                         log_debug("Unknown serialization item '%s'", l);
2553         }
2554
2555         for (;;) {
2556                 Unit *u;
2557                 char name[UNIT_NAME_MAX+2];
2558
2559                 /* Start marker */
2560                 if (!fgets(name, sizeof(name), f)) {
2561                         if (feof(f))
2562                                 r = 0;
2563                         else
2564                                 r = -errno;
2565
2566                         goto finish;
2567                 }
2568
2569                 char_array_0(name);
2570
2571                 if ((r = manager_load_unit(m, strstrip(name), NULL, NULL, &u)) < 0)
2572                         goto finish;
2573
2574                 if ((r = unit_deserialize(u, f, fds)) < 0)
2575                         goto finish;
2576         }
2577
2578 finish:
2579         if (ferror(f)) {
2580                 r = -EIO;
2581                 goto finish;
2582         }
2583
2584         assert(m->n_deserializing > 0);
2585         m->n_deserializing --;
2586
2587         return r;
2588 }
2589
2590 int manager_reload(Manager *m) {
2591         int r, q;
2592         FILE *f;
2593         FDSet *fds;
2594
2595         assert(m);
2596
2597         if ((r = manager_open_serialization(m, &f)) < 0)
2598                 return r;
2599
2600         if (!(fds = fdset_new())) {
2601                 r = -ENOMEM;
2602                 goto finish;
2603         }
2604
2605         if ((r = manager_serialize(m, f, fds)) < 0)
2606                 goto finish;
2607
2608         if (fseeko(f, 0, SEEK_SET) < 0) {
2609                 r = -errno;
2610                 goto finish;
2611         }
2612
2613         /* From here on there is no way back. */
2614         manager_clear_jobs_and_units(m);
2615
2616         /* Find new unit paths */
2617         lookup_paths_free(&m->lookup_paths);
2618         if ((q = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0)
2619                 r = q;
2620
2621         m->n_deserializing ++;
2622
2623         /* First, enumerate what we can from all config files */
2624         if ((q = manager_enumerate(m)) < 0)
2625                 r = q;
2626
2627         /* Second, deserialize our stored data */
2628         if ((q = manager_deserialize(m, f, fds)) < 0)
2629                 r = q;
2630
2631         fclose(f);
2632         f = NULL;
2633
2634         /* Third, fire things up! */
2635         if ((q = manager_coldplug(m)) < 0)
2636                 r = q;
2637
2638         assert(m->n_deserializing > 0);
2639         m->n_deserializing ++;
2640
2641 finish:
2642         if (f)
2643                 fclose(f);
2644
2645         if (fds)
2646                 fdset_free(fds);
2647
2648         return r;
2649 }
2650
2651 bool manager_is_booting_or_shutting_down(Manager *m) {
2652         Unit *u;
2653
2654         assert(m);
2655
2656         /* Is the initial job still around? */
2657         if (manager_get_job(m, 1))
2658                 return true;
2659
2660         /* Is there a job for the shutdown target? */
2661         if (((u = manager_get_unit(m, SPECIAL_SHUTDOWN_TARGET))))
2662                 return !!u->meta.job;
2663
2664         return false;
2665 }
2666
2667 void manager_reset_failed(Manager *m) {
2668         Unit *u;
2669         Iterator i;
2670
2671         assert(m);
2672
2673         HASHMAP_FOREACH(u, m->units, i)
2674                 unit_reset_failed(u);
2675 }
2676
2677 int manager_set_console(Manager *m, const char *console) {
2678         char *c;
2679
2680         assert(m);
2681
2682         if (!(c = strdup(console)))
2683                 return -ENOMEM;
2684
2685         free(m->console);
2686         m->console = c;
2687
2688         log_debug("Using kernel console %s", c);
2689
2690         return 0;
2691 }
2692
2693 bool manager_unit_pending_inactive(Manager *m, const char *name) {
2694         Unit *u;
2695
2696         assert(m);
2697         assert(name);
2698
2699         /* Returns true if the unit is inactive or going down */
2700         if (!(u = manager_get_unit(m, name)))
2701                 return true;
2702
2703         return unit_pending_inactive(u);
2704 }
2705
2706 void manager_check_finished(Manager *m) {
2707         char userspace[FORMAT_TIMESPAN_MAX], kernel[FORMAT_TIMESPAN_MAX], sum[FORMAT_TIMESPAN_MAX];
2708
2709         assert(m);
2710
2711         if (dual_timestamp_is_set(&m->finish_timestamp))
2712                 return;
2713
2714         if (hashmap_size(m->jobs) > 0)
2715                 return;
2716
2717         dual_timestamp_get(&m->finish_timestamp);
2718
2719         if (m->running_as == MANAGER_SYSTEM)
2720                 log_info("Startup finished in %s (kernel) + %s (userspace) = %s.",
2721                          format_timespan(kernel, sizeof(kernel),
2722                                          m->startup_timestamp.monotonic),
2723                          format_timespan(userspace, sizeof(userspace),
2724                                          m->finish_timestamp.monotonic - m->startup_timestamp.monotonic),
2725                          format_timespan(sum, sizeof(sum),
2726                                          m->finish_timestamp.monotonic));
2727         else
2728                 log_debug("Startup finished in %s.",
2729                           format_timespan(userspace, sizeof(userspace),
2730                                           m->finish_timestamp.monotonic - m->startup_timestamp.monotonic));
2731
2732 }
2733
2734 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
2735         [MANAGER_SYSTEM] = "system",
2736         [MANAGER_SESSION] = "session"
2737 };
2738
2739 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);