1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
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.
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.
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/>.
25 #include <sys/epoll.h>
27 #include <sys/signalfd.h>
32 #include <sys/reboot.h>
33 #include <sys/ioctl.h>
35 #include <libcgroup.h>
45 #include "ratelimit.h"
47 #include "mount-setup.h"
48 #include "utmp-wtmp.h"
49 #include "unit-name.h"
51 static int enable_special_signals(Manager *m) {
56 /* Enable that we get SIGINT on control-alt-del */
57 if (reboot(RB_DISABLE_CAD) < 0)
58 log_warning("Failed to enable ctrl-alt-del handling: %m");
60 if ((fd = open_terminal("/dev/tty0", O_RDWR)) < 0)
61 log_warning("Failed to open /dev/tty0: %m");
63 /* Enable that we get SIGWINCH on kbrequest */
64 if (ioctl(fd, KDSIGACCEPT, SIGWINCH) < 0)
65 log_warning("Failed to enable kbrequest handling: %s", strerror(errno));
67 close_nointr_nofail(fd);
73 static int manager_setup_signals(Manager *m) {
75 struct epoll_event ev;
80 /* We are not interested in SIGSTOP and friends. */
82 sa.sa_handler = SIG_DFL;
83 sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
84 assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
86 assert_se(sigemptyset(&mask) == 0);
87 assert_se(sigaddset(&mask, SIGCHLD) == 0);
88 assert_se(sigaddset(&mask, SIGTERM) == 0);
89 assert_se(sigaddset(&mask, SIGHUP) == 0);
90 assert_se(sigaddset(&mask, SIGUSR1) == 0);
91 assert_se(sigaddset(&mask, SIGUSR2) == 0);
92 assert_se(sigaddset(&mask, SIGINT) == 0); /* Kernel sends us this on control-alt-del */
93 assert_se(sigaddset(&mask, SIGWINCH) == 0); /* Kernel sends us this on kbrequest (alt-arrowup) */
94 assert_se(sigaddset(&mask, SIGPWR) == 0); /* Some kernel drivers and upsd send us this on power failure */
95 assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
97 m->signal_watch.type = WATCH_SIGNAL;
98 if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0)
103 ev.data.ptr = &m->signal_watch;
105 if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0)
108 if (m->running_as == MANAGER_INIT)
109 return enable_special_signals(m);
114 static char** session_dirs(void) {
115 const char *home, *e;
116 char *config_home = NULL, *data_home = NULL;
117 char **config_dirs = NULL, **data_dirs = NULL;
118 char **r = NULL, **t;
120 /* Implement the mechanisms defined in
122 * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html
124 * We look in both the config and the data dirs because we
125 * want to encourage that distributors ship their unit files
126 * as data, and allow overriding as configuration.
129 home = getenv("HOME");
131 if ((e = getenv("XDG_CONFIG_HOME"))) {
132 if (asprintf(&config_home, "%s/systemd/session", e) < 0)
136 if (asprintf(&config_home, "%s/.config/systemd/session", home) < 0)
140 if ((e = getenv("XDG_CONFIG_DIRS")))
141 config_dirs = strv_split(e, ":");
143 config_dirs = strv_new("/etc/xdg", NULL);
148 if ((e = getenv("XDG_DATA_HOME"))) {
149 if (asprintf(&data_home, "%s/systemd/session", e) < 0)
153 if (asprintf(&data_home, "%s/.local/share/systemd/session", home) < 0)
157 if ((e = getenv("XDG_DATA_DIRS")))
158 data_dirs = strv_split(e, ":");
160 data_dirs = strv_new("/usr/local/share", "/usr/share", NULL);
165 /* Now merge everything we found. */
167 if (!(t = strv_append(r, config_home)))
173 if (!(t = strv_merge_concat(r, config_dirs, "/systemd/session")))
178 if (!(t = strv_append(r, SESSION_CONFIG_UNIT_PATH)))
184 if (!(t = strv_append(r, data_home)))
190 if (!(t = strv_merge_concat(r, data_dirs, "/systemd/session")))
195 if (!(t = strv_append(r, SESSION_DATA_UNIT_PATH)))
200 if (!strv_path_make_absolute_cwd(r))
205 strv_free(config_dirs);
207 strv_free(data_dirs);
217 static int manager_find_paths(Manager *m) {
223 /* First priority is whatever has been passed to us via env
225 if ((e = getenv("SYSTEMD_UNIT_PATH")))
226 if (!(m->unit_path = split_path_and_make_absolute(e)))
229 if (strv_isempty(m->unit_path)) {
231 /* Nothing is set, so let's figure something out. */
232 strv_free(m->unit_path);
234 if (m->running_as == MANAGER_SESSION) {
235 if (!(m->unit_path = session_dirs()))
238 if (!(m->unit_path = strv_new(
239 SYSTEM_CONFIG_UNIT_PATH, /* /etc/systemd/system/ */
240 SYSTEM_DATA_UNIT_PATH, /* /lib/systemd/system/ */
245 if (m->running_as == MANAGER_INIT) {
246 /* /etc/init.d/ compativility does not matter to users */
248 if ((e = getenv("SYSTEMD_SYSVINIT_PATH")))
249 if (!(m->sysvinit_path = split_path_and_make_absolute(e)))
252 if (strv_isempty(m->sysvinit_path)) {
253 strv_free(m->sysvinit_path);
255 if (!(m->sysvinit_path = strv_new(
256 SYSTEM_SYSVINIT_PATH, /* /etc/init.d/ */
261 if ((e = getenv("SYSTEMD_SYSVRCND_PATH")))
262 if (!(m->sysvrcnd_path = split_path_and_make_absolute(e)))
265 if (strv_isempty(m->sysvrcnd_path)) {
266 strv_free(m->sysvrcnd_path);
268 if (!(m->sysvrcnd_path = strv_new(
269 SYSTEM_SYSVRCND_PATH, /* /etc/rcN.d/ */
275 strv_uniq(m->unit_path);
276 strv_uniq(m->sysvinit_path);
277 strv_uniq(m->sysvrcnd_path);
279 assert(!strv_isempty(m->unit_path));
280 if (!(t = strv_join(m->unit_path, "\n\t")))
282 log_debug("Looking for unit files in:\n\t%s", t);
285 if (!strv_isempty(m->sysvinit_path)) {
287 if (!(t = strv_join(m->sysvinit_path, "\n\t")))
290 log_debug("Looking for SysV init scripts in:\n\t%s", t);
293 log_debug("Ignoring SysV init scripts.");
295 if (!strv_isempty(m->sysvrcnd_path)) {
297 if (!(t = strv_join(m->sysvrcnd_path, "\n\t")))
300 log_debug("Looking for SysV rcN.d links in:\n\t%s", t);
303 log_debug("Ignoring SysV rcN.d links.");
308 int manager_new(ManagerRunningAs running_as, bool confirm_spawn, Manager **_m) {
313 assert(running_as >= 0);
314 assert(running_as < _MANAGER_RUNNING_AS_MAX);
316 if (!(m = new0(Manager, 1)))
319 m->boot_timestamp = now(CLOCK_REALTIME);
321 m->running_as = running_as;
322 m->confirm_spawn = confirm_spawn;
323 m->name_data_slot = -1;
325 m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_fd = -1;
326 m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */
328 if (!(m->units = hashmap_new(string_hash_func, string_compare_func)))
331 if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
334 if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
337 if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
340 if (!(m->cgroup_bondings = hashmap_new(string_hash_func, string_compare_func)))
343 if (!(m->watch_bus = hashmap_new(string_hash_func, string_compare_func)))
346 if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
349 if ((r = manager_find_paths(m)) < 0)
352 if ((r = manager_setup_signals(m)) < 0)
355 if ((r = manager_setup_cgroup(m)) < 0)
358 /* Try to connect to the busses, if possible. */
359 if ((r = bus_init_system(m)) < 0 ||
360 (r = bus_init_api(m)) < 0)
371 static unsigned manager_dispatch_cleanup_queue(Manager *m) {
377 while ((meta = m->cleanup_queue)) {
378 assert(meta->in_cleanup_queue);
380 unit_free(UNIT(meta));
387 void manager_free(Manager *m) {
394 while ((j = hashmap_first(m->transaction_jobs)))
397 while ((u = hashmap_first(m->units)))
400 manager_dispatch_cleanup_queue(m);
402 for (c = 0; c < _UNIT_TYPE_MAX; c++)
403 if (unit_vtable[c]->shutdown)
404 unit_vtable[c]->shutdown(m);
406 manager_shutdown_cgroup(m);
411 hashmap_free(m->units);
412 hashmap_free(m->jobs);
413 hashmap_free(m->transaction_jobs);
414 hashmap_free(m->watch_pids);
415 hashmap_free(m->watch_bus);
417 if (m->epoll_fd >= 0)
418 close_nointr(m->epoll_fd);
419 if (m->signal_watch.fd >= 0)
420 close_nointr(m->signal_watch.fd);
422 strv_free(m->unit_path);
423 strv_free(m->sysvinit_path);
424 strv_free(m->sysvrcnd_path);
426 free(m->cgroup_controller);
427 free(m->cgroup_hierarchy);
429 assert(hashmap_isempty(m->cgroup_bondings));
430 hashmap_free(m->cgroup_bondings);
435 int manager_coldplug(Manager *m) {
444 /* First, let's ask every type to load all units from
445 * disk/kernel that it might know */
446 for (c = 0; c < _UNIT_TYPE_MAX; c++)
447 if (unit_vtable[c]->enumerate)
448 if ((r = unit_vtable[c]->enumerate(m)) < 0)
451 manager_dispatch_load_queue(m);
453 /* Then, let's set up their initial state. */
454 HASHMAP_FOREACH_KEY(u, k, m->units, i) {
460 if (UNIT_VTABLE(u)->coldplug)
461 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
465 /* Now that the initial devices are available, let's see if we
466 * can write the utmp file */
467 manager_write_utmp_reboot(m);
472 static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) {
476 /* Deletes one job from the transaction */
478 manager_transaction_unlink_job(m, j, delete_dependencies);
484 static void transaction_delete_unit(Manager *m, Unit *u) {
487 /* Deletes all jobs associated with a certain unit from the
490 while ((j = hashmap_get(m->transaction_jobs, u)))
491 transaction_delete_job(m, j, true);
494 static void transaction_clean_dependencies(Manager *m) {
500 /* Drops all dependencies of all installed jobs */
502 HASHMAP_FOREACH(j, m->jobs, i) {
503 while (j->subject_list)
504 job_dependency_free(j->subject_list);
505 while (j->object_list)
506 job_dependency_free(j->object_list);
509 assert(!m->transaction_anchor);
512 static void transaction_abort(Manager *m) {
517 while ((j = hashmap_first(m->transaction_jobs)))
519 transaction_delete_job(m, j, true);
523 assert(hashmap_isempty(m->transaction_jobs));
525 transaction_clean_dependencies(m);
528 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
533 /* A recursive sweep through the graph that marks all units
534 * that matter to the anchor job, i.e. are directly or
535 * indirectly a dependency of the anchor job via paths that
536 * are fully marked as mattering. */
541 l = m->transaction_anchor;
543 LIST_FOREACH(subject, l, l) {
545 /* This link does not matter */
549 /* This unit has already been marked */
550 if (l->object->generation == generation)
553 l->object->matters_to_anchor = true;
554 l->object->generation = generation;
556 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
560 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
561 JobDependency *l, *last;
565 assert(j->unit == other->unit);
566 assert(!j->installed);
568 /* Merges 'other' into 'j' and then deletes j. */
571 j->state = JOB_WAITING;
572 j->override = j->override || other->override;
574 j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
576 /* Patch us in as new owner of the JobDependency objects */
578 LIST_FOREACH(subject, l, other->subject_list) {
579 assert(l->subject == other);
584 /* Merge both lists */
586 last->subject_next = j->subject_list;
588 j->subject_list->subject_prev = last;
589 j->subject_list = other->subject_list;
592 /* Patch us in as new owner of the JobDependency objects */
594 LIST_FOREACH(object, l, other->object_list) {
595 assert(l->object == other);
600 /* Merge both lists */
602 last->object_next = j->object_list;
604 j->object_list->object_prev = last;
605 j->object_list = other->object_list;
608 /* Kill the other job */
609 other->subject_list = NULL;
610 other->object_list = NULL;
611 transaction_delete_job(m, other, true);
614 static int delete_one_unmergeable_job(Manager *m, Job *j) {
619 /* Tries to delete one item in the linked list
620 * j->transaction_next->transaction_next->... that conflicts
621 * whith another one, in an attempt to make an inconsistent
622 * transaction work. */
624 /* We rely here on the fact that if a merged with b does not
625 * merge with c, either a or b merge with c neither */
626 LIST_FOREACH(transaction, j, j)
627 LIST_FOREACH(transaction, k, j->transaction_next) {
630 /* Is this one mergeable? Then skip it */
631 if (job_type_is_mergeable(j->type, k->type))
634 /* Ok, we found two that conflict, let's see if we can
635 * drop one of them */
636 if (!j->matters_to_anchor)
638 else if (!k->matters_to_anchor)
643 /* Ok, we can drop one, so let's do so. */
644 log_debug("Trying to fix job merging by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type));
645 transaction_delete_job(m, d, true);
652 static int transaction_merge_jobs(Manager *m) {
659 /* First step, check whether any of the jobs for one specific
660 * task conflict. If so, try to drop one of them. */
661 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
666 LIST_FOREACH(transaction, k, j->transaction_next) {
667 if ((r = job_type_merge(&t, k->type)) >= 0)
670 /* OK, we could not merge all jobs for this
671 * action. Let's see if we can get rid of one
674 if ((r = delete_one_unmergeable_job(m, j)) >= 0)
675 /* Ok, we managed to drop one, now
676 * let's ask our callers to call us
677 * again after garbage collecting */
680 /* We couldn't merge anything. Failure */
685 /* Second step, merge the jobs. */
686 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
690 /* Merge all transactions */
691 LIST_FOREACH(transaction, k, j->transaction_next)
692 assert_se(job_type_merge(&t, k->type) == 0);
694 /* If an active job is mergeable, merge it too */
695 if (j->unit->meta.job)
696 job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
698 while ((k = j->transaction_next)) {
700 transaction_merge_and_delete_job(m, k, j, t);
703 transaction_merge_and_delete_job(m, j, k, t);
706 assert(!j->transaction_next);
707 assert(!j->transaction_prev);
713 static void transaction_drop_redundant(Manager *m) {
718 /* Goes through the transaction and removes all jobs that are
727 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
728 bool changes_something = false;
731 LIST_FOREACH(transaction, k, j) {
733 if (!job_is_anchor(k) &&
734 job_type_is_redundant(k->type, unit_active_state(k->unit)))
737 changes_something = true;
741 if (changes_something)
744 log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type));
745 transaction_delete_job(m, j, false);
753 static bool unit_matters_to_anchor(Unit *u, Job *j) {
755 assert(!j->transaction_prev);
757 /* Checks whether at least one of the jobs for this unit
758 * matters to the anchor. */
760 LIST_FOREACH(transaction, j, j)
761 if (j->matters_to_anchor)
767 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation) {
774 assert(!j->transaction_prev);
776 /* Does a recursive sweep through the ordering graph, looking
777 * for a cycle. If we find cycle we try to break it. */
779 /* Did we find a cycle? */
780 if (j->marker && j->generation == generation) {
783 /* So, we already have been here. We have a
784 * cycle. Let's try to break it. We go backwards in
785 * our path and try to find a suitable job to
786 * remove. We use the marker to find our way back,
787 * since smart how we are we stored our way back in
790 log_debug("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type));
792 for (k = from; k; k = (k->generation == generation ? k->marker : NULL)) {
794 log_debug("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type));
797 !unit_matters_to_anchor(k->unit, k)) {
798 /* Ok, we can drop this one, so let's
800 log_debug("Breaking order cycle by deleting job %s/%s", k->unit->meta.id, job_type_to_string(k->type));
801 transaction_delete_unit(m, k->unit);
805 /* Check if this in fact was the beginning of
811 log_debug("Unable to break cycle");
816 /* Make the marker point to where we come from, so that we can
817 * find our way backwards if we want to break a cycle */
819 j->generation = generation;
821 /* We assume that the the dependencies are bidirectional, and
822 * hence can ignore UNIT_AFTER */
823 SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
826 /* Is there a job for this unit? */
827 if (!(o = hashmap_get(m->transaction_jobs, u)))
829 /* Ok, there is no job for this in the
830 * transaction, but maybe there is already one
832 if (!(o = u->meta.job))
835 if ((r = transaction_verify_order_one(m, o, j, generation)) < 0)
839 /* Ok, let's backtrack, and remember that this entry is not on
840 * our path anymore. */
846 static int transaction_verify_order(Manager *m, unsigned *generation) {
854 /* Check if the ordering graph is cyclic. If it is, try to fix
855 * that up by dropping one of the jobs. */
857 HASHMAP_FOREACH(j, m->transaction_jobs, i)
858 if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0)
864 static void transaction_collect_garbage(Manager *m) {
869 /* Drop jobs that are not required by any other job */
877 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
881 log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type));
882 transaction_delete_job(m, j, true);
890 static int transaction_is_destructive(Manager *m, JobMode mode) {
896 /* Checks whether applying this transaction means that
897 * existing jobs would be replaced */
899 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
902 assert(!j->transaction_prev);
903 assert(!j->transaction_next);
905 if (j->unit->meta.job &&
906 j->unit->meta.job != j &&
907 !job_type_is_superset(j->type, j->unit->meta.job->type))
914 static void transaction_minimize_impact(Manager *m) {
918 /* Drops all unnecessary jobs that reverse already active jobs
919 * or that stop a running service. */
927 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
928 LIST_FOREACH(transaction, j, j) {
929 bool stops_running_service, changes_existing_job;
931 /* If it matters, we shouldn't drop it */
932 if (j->matters_to_anchor)
935 /* Would this stop a running service?
936 * Would this change an existing job?
937 * If so, let's drop this entry */
939 stops_running_service =
940 j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
942 changes_existing_job =
943 j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->state);
945 if (!stops_running_service && !changes_existing_job)
948 if (stops_running_service)
949 log_debug("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type));
951 if (changes_existing_job)
952 log_debug("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type));
954 /* Ok, let's get rid of this */
955 log_debug("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type));
957 transaction_delete_job(m, j, true);
969 static int transaction_apply(Manager *m, JobMode mode) {
974 /* Moves the transaction jobs to the set of active jobs */
976 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
978 assert(!j->transaction_prev);
979 assert(!j->transaction_next);
984 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
988 while ((j = hashmap_steal_first(m->transaction_jobs))) {
992 if (j->unit->meta.job)
993 job_free(j->unit->meta.job);
995 j->unit->meta.job = j;
998 /* We're fully installed. Now let's free data we don't
1001 assert(!j->transaction_next);
1002 assert(!j->transaction_prev);
1004 job_add_to_run_queue(j);
1005 job_add_to_dbus_queue(j);
1008 /* As last step, kill all remaining job dependencies. */
1009 transaction_clean_dependencies(m);
1015 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1019 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1025 static int transaction_activate(Manager *m, JobMode mode) {
1027 unsigned generation = 1;
1031 /* This applies the changes recorded in transaction_jobs to
1032 * the actual list of jobs, if possible. */
1034 /* First step: figure out which jobs matter */
1035 transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1037 /* Second step: Try not to stop any running services if
1038 * we don't have to. Don't try to reverse running
1039 * jobs if we don't have to. */
1040 transaction_minimize_impact(m);
1042 /* Third step: Drop redundant jobs */
1043 transaction_drop_redundant(m);
1046 /* Fourth step: Let's remove unneeded jobs that might
1048 transaction_collect_garbage(m);
1050 /* Fifth step: verify order makes sense and correct
1051 * cycles if necessary and possible */
1052 if ((r = transaction_verify_order(m, &generation)) >= 0)
1056 log_debug("Requested transaction contains an unfixable cyclic ordering dependency: %s", strerror(-r));
1060 /* Let's see if the resulting transaction ordering
1061 * graph is still cyclic... */
1065 /* Sixth step: let's drop unmergeable entries if
1066 * necessary and possible, merge entries we can
1068 if ((r = transaction_merge_jobs(m)) >= 0)
1072 log_debug("Requested transaction contains unmergable jobs: %s", strerror(-r));
1076 /* Seventh step: an entry got dropped, let's garbage
1077 * collect its dependencies. */
1078 transaction_collect_garbage(m);
1080 /* Let's see if the resulting transaction still has
1081 * unmergeable entries ... */
1084 /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1085 transaction_drop_redundant(m);
1087 /* Ninth step: check whether we can actually apply this */
1088 if (mode == JOB_FAIL)
1089 if ((r = transaction_is_destructive(m, mode)) < 0) {
1090 log_debug("Requested transaction contradicts existing jobs: %s", strerror(-r));
1094 /* Tenth step: apply changes */
1095 if ((r = transaction_apply(m, mode)) < 0) {
1096 log_debug("Failed to apply transaction: %s", strerror(-r));
1100 assert(hashmap_isempty(m->transaction_jobs));
1101 assert(!m->transaction_anchor);
1106 transaction_abort(m);
1110 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1117 /* Looks for an axisting prospective job and returns that. If
1118 * it doesn't exist it is created and added to the prospective
1121 f = hashmap_get(m->transaction_jobs, unit);
1123 LIST_FOREACH(transaction, j, f) {
1124 assert(j->unit == unit);
1126 if (j->type == type) {
1133 if (unit->meta.job && unit->meta.job->type == type)
1135 else if (!(j = job_new(m, type, unit)))
1140 j->matters_to_anchor = false;
1141 j->override = override;
1143 LIST_PREPEND(Job, transaction, f, j);
1145 if ((r = hashmap_replace(m->transaction_jobs, unit, f)) < 0) {
1153 log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1158 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1162 if (j->transaction_prev)
1163 j->transaction_prev->transaction_next = j->transaction_next;
1164 else if (j->transaction_next)
1165 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1167 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1169 if (j->transaction_next)
1170 j->transaction_next->transaction_prev = j->transaction_prev;
1172 j->transaction_prev = j->transaction_next = NULL;
1174 while (j->subject_list)
1175 job_dependency_free(j->subject_list);
1177 while (j->object_list) {
1178 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1180 job_dependency_free(j->object_list);
1182 if (other && delete_dependencies) {
1183 log_debug("Deleting job %s/%s as dependency of job %s/%s",
1184 other->unit->meta.id, job_type_to_string(other->type),
1185 j->unit->meta.id, job_type_to_string(j->type));
1186 transaction_delete_job(m, other, delete_dependencies);
1191 static int transaction_add_job_and_dependencies(
1206 assert(type < _JOB_TYPE_MAX);
1209 if (unit->meta.load_state != UNIT_LOADED)
1212 if (!unit_job_is_applicable(unit, type))
1215 /* First add the job. */
1216 if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1219 /* Then, add a link to the job. */
1220 if (!job_dependency_new(by, ret, matters))
1224 /* Finally, recursively add in all dependencies. */
1225 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1226 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1227 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1230 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1231 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, NULL)) < 0 && r != -EBADR)
1232 log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1234 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1235 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, NULL)) < 0)
1236 log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1238 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1239 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1242 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1243 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, NULL)) < 0 && r != -EBADR)
1244 log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1246 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1247 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1250 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1252 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1253 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1257 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1269 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, Job **_ret) {
1274 assert(type < _JOB_TYPE_MAX);
1276 assert(mode < _JOB_MODE_MAX);
1278 log_debug("Trying to enqueue job %s/%s", unit->meta.id, job_type_to_string(type));
1280 if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, &ret)) < 0) {
1281 transaction_abort(m);
1285 if ((r = transaction_activate(m, mode)) < 0)
1288 log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id);
1296 int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, Job **_ret) {
1301 assert(type < _JOB_TYPE_MAX);
1303 assert(mode < _JOB_MODE_MAX);
1305 if ((r = manager_load_unit(m, name, NULL, &unit)) < 0)
1308 return manager_add_job(m, type, unit, mode, override, _ret);
1311 Job *manager_get_job(Manager *m, uint32_t id) {
1314 return hashmap_get(m->jobs, UINT32_TO_PTR(id));
1317 Unit *manager_get_unit(Manager *m, const char *name) {
1321 return hashmap_get(m->units, name);
1324 unsigned manager_dispatch_load_queue(Manager *m) {
1330 /* Make sure we are not run recursively */
1331 if (m->dispatching_load_queue)
1334 m->dispatching_load_queue = true;
1336 /* Dispatches the load queue. Takes a unit from the queue and
1337 * tries to load its data until the queue is empty */
1339 while ((meta = m->load_queue)) {
1340 assert(meta->in_load_queue);
1342 unit_load(UNIT(meta));
1346 m->dispatching_load_queue = false;
1350 int manager_load_unit(Manager *m, const char *name, const char *path, Unit **_ret) {
1355 assert(name || path);
1357 /* This will load the service information files, but not actually
1358 * start any services or anything. */
1360 if (path && !is_path(path))
1364 name = file_name_from_path(path);
1366 if (!unit_name_is_valid(name))
1369 if ((ret = manager_get_unit(m, name))) {
1374 if (!(ret = unit_new(m)))
1378 if (!(ret->meta.fragment_path = strdup(path))) {
1383 if ((r = unit_add_name(ret, name)) < 0) {
1388 unit_add_to_load_queue(ret);
1389 unit_add_to_dbus_queue(ret);
1391 manager_dispatch_load_queue(m);
1394 *_ret = unit_follow_merge(ret);
1399 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1406 HASHMAP_FOREACH(j, s->jobs, i)
1407 job_dump(j, f, prefix);
1410 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1418 HASHMAP_FOREACH_KEY(u, t, s->units, i)
1419 if (u->meta.id == t)
1420 unit_dump(u, f, prefix);
1423 void manager_clear_jobs(Manager *m) {
1428 transaction_abort(m);
1430 while ((j = hashmap_first(m->jobs)))
1434 unsigned manager_dispatch_run_queue(Manager *m) {
1438 if (m->dispatching_run_queue)
1441 m->dispatching_run_queue = true;
1443 while ((j = m->run_queue)) {
1444 assert(j->installed);
1445 assert(j->in_run_queue);
1447 job_run_and_invalidate(j);
1451 m->dispatching_run_queue = false;
1455 unsigned manager_dispatch_dbus_queue(Manager *m) {
1462 if (m->dispatching_dbus_queue)
1465 m->dispatching_dbus_queue = true;
1467 while ((meta = m->dbus_unit_queue)) {
1468 assert(meta->in_dbus_queue);
1470 bus_unit_send_change_signal(UNIT(meta));
1474 while ((j = m->dbus_job_queue)) {
1475 assert(j->in_dbus_queue);
1477 bus_job_send_change_signal(j);
1481 m->dispatching_dbus_queue = false;
1485 static int manager_dispatch_sigchld(Manager *m) {
1494 /* First we call waitd() for a PID and do not reap the
1495 * zombie. That way we can still access /proc/$PID for
1496 * it while it is a zombie. */
1497 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1499 if (errno == ECHILD)
1511 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1514 get_process_name(si.si_pid, &name);
1515 log_debug("Got SIGCHLD for process %llu (%s)", (unsigned long long) si.si_pid, strna(name));
1519 /* And now, we actually reap the zombie. */
1520 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1527 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1530 log_debug("Child %llu died (code=%s, status=%i/%s)",
1531 (long long unsigned) si.si_pid,
1532 sigchld_code_to_string(si.si_code),
1534 strna(si.si_code == CLD_EXITED ? exit_status_to_string(si.si_status) : strsignal(si.si_status)));
1536 if (!(u = hashmap_remove(m->watch_pids, UINT32_TO_PTR(si.si_pid))))
1539 log_debug("Child %llu belongs to %s", (long long unsigned) si.si_pid, u->meta.id);
1541 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1547 static void manager_start_target(Manager *m, const char *name) {
1550 if ((r = manager_add_job_by_name(m, JOB_START, name, JOB_REPLACE, true, NULL)) < 0)
1551 log_error("Failed to enqueue %s job: %s", name, strerror(-r));
1554 static int manager_process_signal_fd(Manager *m, bool *quit) {
1556 struct signalfd_siginfo sfsi;
1557 bool sigchld = false;
1562 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1567 if (errno == EAGAIN)
1573 switch (sfsi.ssi_signo) {
1582 if (m->running_as == MANAGER_INIT) {
1583 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET);
1592 if (m->running_as == MANAGER_INIT)
1593 manager_start_target(m, SPECIAL_KBREQUEST_TARGET);
1595 /* This is a nop on non-init */
1599 if (m->running_as == MANAGER_INIT)
1600 manager_start_target(m, SPECIAL_SIGPWR_TARGET);
1602 /* This is a nop on non-init */
1606 manager_dump_units(m, stdout, "\t");
1607 manager_dump_jobs(m, stdout, "\t");
1613 u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
1615 if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
1616 log_info("Trying to reconnect to bus...");
1621 if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
1622 log_info("Loading D-Bus service...");
1623 manager_start_target(m, SPECIAL_DBUS_SERVICE);
1630 log_info("Got unhandled signal <%s>.", strsignal(sfsi.ssi_signo));
1635 return manager_dispatch_sigchld(m);
1640 static int process_event(Manager *m, struct epoll_event *ev, bool *quit) {
1647 assert(w = ev->data.ptr);
1653 /* An incoming signal? */
1654 if (ev->events != EPOLLIN)
1657 if ((r = manager_process_signal_fd(m, quit)) < 0)
1664 /* Some fd event, to be dispatched to the units */
1665 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
1672 /* Some timer event, to be dispatched to the units */
1673 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
1675 if (k < 0 && (errno == EINTR || errno == EAGAIN))
1678 return k < 0 ? -errno : -EIO;
1681 UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
1686 /* Some mount table change, intended for the mount subsystem */
1687 mount_fd_event(m, ev->events);
1691 /* Some notification from udev, intended for the device subsystem */
1692 device_fd_event(m, ev->events);
1695 case WATCH_DBUS_WATCH:
1696 bus_watch_event(m, w, ev->events);
1699 case WATCH_DBUS_TIMEOUT:
1700 bus_timeout_event(m, w, ev->events);
1704 assert_not_reached("Unknown epoll event type.");
1710 int manager_loop(Manager *m) {
1714 RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
1719 struct epoll_event event;
1722 if (!ratelimit_test(&rl)) {
1723 /* Yay, something is going seriously wrong, pause a little */
1724 log_warning("Looping too fast. Throttling execution a little.");
1728 if (manager_dispatch_cleanup_queue(m) > 0)
1731 if (manager_dispatch_load_queue(m) > 0)
1734 if (manager_dispatch_run_queue(m) > 0)
1737 if (bus_dispatch(m) > 0)
1740 if (manager_dispatch_dbus_queue(m) > 0)
1743 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
1745 if (errno == -EINTR)
1753 if ((r = process_event(m, &event, &quit)) < 0)
1760 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
1768 if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
1771 if (!(n = bus_path_unescape(s+31)))
1774 u = manager_get_unit(m, n);
1785 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
1794 if (!startswith(s, "/org/freedesktop/systemd1/job/"))
1797 if ((r = safe_atou(s + 30, &id)) < 0)
1800 if (!(j = manager_get_job(m, id)))
1808 static bool manager_utmp_good(Manager *m) {
1813 if ((r = mount_path_is_mounted(m, _PATH_UTMPX)) <= 0) {
1816 log_warning("Failed to determine whether " _PATH_UTMPX " is mounted: %s", strerror(-r));
1824 void manager_write_utmp_reboot(Manager *m) {
1829 if (m->utmp_reboot_written)
1832 if (m->running_as != MANAGER_INIT)
1835 if (!manager_utmp_good(m))
1838 if ((r = utmp_put_reboot(m->boot_timestamp)) < 0) {
1840 if (r != -ENOENT && r != -EROFS)
1841 log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
1846 m->utmp_reboot_written = true;
1849 void manager_write_utmp_runlevel(Manager *m, Unit *u) {
1855 if (u->meta.type != UNIT_TARGET)
1858 if (m->running_as != MANAGER_INIT)
1861 if (!manager_utmp_good(m))
1864 if ((runlevel = target_get_runlevel(TARGET(u))) <= 0)
1867 if ((r = utmp_put_runlevel(0, runlevel, 0)) < 0) {
1869 if (r != -ENOENT && r != -EROFS)
1870 log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
1874 void manager_dispatch_bus_name_owner_changed(
1877 const char* old_owner,
1878 const char *new_owner) {
1885 if (!(u = hashmap_get(m->watch_bus, name)))
1888 UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
1891 void manager_dispatch_bus_query_pid_done(
1902 if (!(u = hashmap_get(m->watch_bus, name)))
1905 UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
1908 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
1909 [MANAGER_INIT] = "init",
1910 [MANAGER_SYSTEM] = "system",
1911 [MANAGER_SESSION] = "session"
1914 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);