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>
38 #include <sys/types.h>
47 #include "ratelimit.h"
49 #include "mount-setup.h"
50 #include "utmp-wtmp.h"
51 #include "unit-name.h"
52 #include "dbus-unit.h"
55 static int enable_special_signals(Manager *m) {
60 /* Enable that we get SIGINT on control-alt-del */
61 if (reboot(RB_DISABLE_CAD) < 0)
62 log_warning("Failed to enable ctrl-alt-del handling: %m");
64 if ((fd = open_terminal("/dev/tty0", O_RDWR)) < 0)
65 log_warning("Failed to open /dev/tty0: %m");
67 /* Enable that we get SIGWINCH on kbrequest */
68 if (ioctl(fd, KDSIGACCEPT, SIGWINCH) < 0)
69 log_warning("Failed to enable kbrequest handling: %s", strerror(errno));
71 close_nointr_nofail(fd);
77 static int manager_setup_signals(Manager *m) {
79 struct epoll_event ev;
84 /* We are not interested in SIGSTOP and friends. */
86 sa.sa_handler = SIG_DFL;
87 sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
88 assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
90 assert_se(sigemptyset(&mask) == 0);
91 assert_se(sigaddset(&mask, SIGCHLD) == 0);
92 assert_se(sigaddset(&mask, SIGTERM) == 0);
93 assert_se(sigaddset(&mask, SIGHUP) == 0);
94 assert_se(sigaddset(&mask, SIGUSR1) == 0);
95 assert_se(sigaddset(&mask, SIGUSR2) == 0);
96 assert_se(sigaddset(&mask, SIGINT) == 0); /* Kernel sends us this on control-alt-del */
97 assert_se(sigaddset(&mask, SIGWINCH) == 0); /* Kernel sends us this on kbrequest (alt-arrowup) */
98 assert_se(sigaddset(&mask, SIGPWR) == 0); /* Some kernel drivers and upsd send us this on power failure */
99 assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
101 m->signal_watch.type = WATCH_SIGNAL;
102 if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0)
107 ev.data.ptr = &m->signal_watch;
109 if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0)
112 if (m->running_as == MANAGER_INIT)
113 return enable_special_signals(m);
118 static char** session_dirs(void) {
119 const char *home, *e;
120 char *config_home = NULL, *data_home = NULL;
121 char **config_dirs = NULL, **data_dirs = NULL;
122 char **r = NULL, **t;
124 /* Implement the mechanisms defined in
126 * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html
128 * We look in both the config and the data dirs because we
129 * want to encourage that distributors ship their unit files
130 * as data, and allow overriding as configuration.
133 home = getenv("HOME");
135 if ((e = getenv("XDG_CONFIG_HOME"))) {
136 if (asprintf(&config_home, "%s/systemd/session", e) < 0)
140 if (asprintf(&config_home, "%s/.config/systemd/session", home) < 0)
144 if ((e = getenv("XDG_CONFIG_DIRS")))
145 config_dirs = strv_split(e, ":");
147 config_dirs = strv_new("/etc/xdg", NULL);
152 if ((e = getenv("XDG_DATA_HOME"))) {
153 if (asprintf(&data_home, "%s/systemd/session", e) < 0)
157 if (asprintf(&data_home, "%s/.local/share/systemd/session", home) < 0)
161 if ((e = getenv("XDG_DATA_DIRS")))
162 data_dirs = strv_split(e, ":");
164 data_dirs = strv_new("/usr/local/share", "/usr/share", NULL);
169 /* Now merge everything we found. */
171 if (!(t = strv_append(r, config_home)))
177 if (!(t = strv_merge_concat(r, config_dirs, "/systemd/session")))
182 if (!(t = strv_append(r, SESSION_CONFIG_UNIT_PATH)))
188 if (!(t = strv_append(r, data_home)))
194 if (!(t = strv_merge_concat(r, data_dirs, "/systemd/session")))
199 if (!(t = strv_append(r, SESSION_DATA_UNIT_PATH)))
204 if (!strv_path_make_absolute_cwd(r))
209 strv_free(config_dirs);
211 strv_free(data_dirs);
221 static int manager_find_paths(Manager *m) {
227 /* First priority is whatever has been passed to us via env
229 if ((e = getenv("SYSTEMD_UNIT_PATH")))
230 if (!(m->unit_path = split_path_and_make_absolute(e)))
233 if (strv_isempty(m->unit_path)) {
235 /* Nothing is set, so let's figure something out. */
236 strv_free(m->unit_path);
238 if (m->running_as == MANAGER_SESSION) {
239 if (!(m->unit_path = session_dirs()))
242 if (!(m->unit_path = strv_new(
243 SYSTEM_CONFIG_UNIT_PATH, /* /etc/systemd/system/ */
244 SYSTEM_DATA_UNIT_PATH, /* /lib/systemd/system/ */
249 if (m->running_as == MANAGER_INIT) {
250 /* /etc/init.d/ compativility does not matter to users */
252 if ((e = getenv("SYSTEMD_SYSVINIT_PATH")))
253 if (!(m->sysvinit_path = split_path_and_make_absolute(e)))
256 if (strv_isempty(m->sysvinit_path)) {
257 strv_free(m->sysvinit_path);
259 if (!(m->sysvinit_path = strv_new(
260 SYSTEM_SYSVINIT_PATH, /* /etc/init.d/ */
265 if ((e = getenv("SYSTEMD_SYSVRCND_PATH")))
266 if (!(m->sysvrcnd_path = split_path_and_make_absolute(e)))
269 if (strv_isempty(m->sysvrcnd_path)) {
270 strv_free(m->sysvrcnd_path);
272 if (!(m->sysvrcnd_path = strv_new(
273 SYSTEM_SYSVRCND_PATH, /* /etc/rcN.d/ */
279 strv_uniq(m->unit_path);
280 strv_uniq(m->sysvinit_path);
281 strv_uniq(m->sysvrcnd_path);
283 assert(!strv_isempty(m->unit_path));
284 if (!(t = strv_join(m->unit_path, "\n\t")))
286 log_debug("Looking for unit files in:\n\t%s", t);
289 if (!strv_isempty(m->sysvinit_path)) {
291 if (!(t = strv_join(m->sysvinit_path, "\n\t")))
294 log_debug("Looking for SysV init scripts in:\n\t%s", t);
297 log_debug("Ignoring SysV init scripts.");
299 if (!strv_isempty(m->sysvrcnd_path)) {
301 if (!(t = strv_join(m->sysvrcnd_path, "\n\t")))
304 log_debug("Looking for SysV rcN.d links in:\n\t%s", t);
307 log_debug("Ignoring SysV rcN.d links.");
312 int manager_new(ManagerRunningAs running_as, bool confirm_spawn, Manager **_m) {
317 assert(running_as >= 0);
318 assert(running_as < _MANAGER_RUNNING_AS_MAX);
320 if (!(m = new0(Manager, 1)))
323 m->boot_timestamp = now(CLOCK_REALTIME);
325 m->running_as = running_as;
326 m->confirm_spawn = confirm_spawn;
327 m->name_data_slot = -1;
328 m->exit_code = _MANAGER_EXIT_CODE_INVALID;
330 m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_fd = -1;
331 m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */
333 if (!(m->units = hashmap_new(string_hash_func, string_compare_func)))
336 if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
339 if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
342 if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
345 if (!(m->cgroup_bondings = hashmap_new(string_hash_func, string_compare_func)))
348 if (!(m->watch_bus = hashmap_new(string_hash_func, string_compare_func)))
351 if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
354 if ((r = manager_find_paths(m)) < 0)
357 if ((r = manager_setup_signals(m)) < 0)
360 if ((r = manager_setup_cgroup(m)) < 0)
363 /* Try to connect to the busses, if possible. */
364 if ((r = bus_init_system(m)) < 0 ||
365 (r = bus_init_api(m)) < 0)
376 static unsigned manager_dispatch_cleanup_queue(Manager *m) {
382 while ((meta = m->cleanup_queue)) {
383 assert(meta->in_cleanup_queue);
385 unit_free(UNIT(meta));
392 static void manager_clear_jobs_and_units(Manager *m) {
398 while ((j = hashmap_first(m->transaction_jobs)))
401 while ((u = hashmap_first(m->units)))
405 void manager_free(Manager *m) {
410 manager_clear_jobs_and_units(m);
412 for (c = 0; c < _UNIT_TYPE_MAX; c++)
413 if (unit_vtable[c]->shutdown)
414 unit_vtable[c]->shutdown(m);
416 /* If we reexecute ourselves, we keep the root cgroup
418 manager_shutdown_cgroup(m, m->exit_code != MANAGER_REEXECUTE);
423 hashmap_free(m->units);
424 hashmap_free(m->jobs);
425 hashmap_free(m->transaction_jobs);
426 hashmap_free(m->watch_pids);
427 hashmap_free(m->watch_bus);
429 if (m->epoll_fd >= 0)
430 close_nointr_nofail(m->epoll_fd);
431 if (m->signal_watch.fd >= 0)
432 close_nointr_nofail(m->signal_watch.fd);
434 strv_free(m->unit_path);
435 strv_free(m->sysvinit_path);
436 strv_free(m->sysvrcnd_path);
438 free(m->cgroup_controller);
439 free(m->cgroup_hierarchy);
441 hashmap_free(m->cgroup_bondings);
446 int manager_enumerate(Manager *m) {
452 /* Let's ask every type to load all units from disk/kernel
453 * that it might know */
454 for (c = 0; c < _UNIT_TYPE_MAX; c++)
455 if (unit_vtable[c]->enumerate)
456 if ((q = unit_vtable[c]->enumerate(m)) < 0)
459 manager_dispatch_load_queue(m);
463 int manager_coldplug(Manager *m) {
471 /* Then, let's set up their initial state. */
472 HASHMAP_FOREACH_KEY(u, k, m->units, i) {
478 if (UNIT_VTABLE(u)->coldplug)
479 if ((q = UNIT_VTABLE(u)->coldplug(u)) < 0)
486 int manager_startup(Manager *m, FILE *serialization, FDSet *fds) {
491 /* First, enumerate what we can from all config files */
492 r = manager_enumerate(m);
494 /* Second, deserialize if there is something to deserialize */
496 if ((q = manager_deserialize(m, serialization, fds)) < 0)
499 /* Third, fire things up! */
500 if ((q = manager_coldplug(m)) < 0)
503 /* Now that the initial devices are available, let's see if we
504 * can write the utmp file */
505 manager_write_utmp_reboot(m);
510 static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) {
514 /* Deletes one job from the transaction */
516 manager_transaction_unlink_job(m, j, delete_dependencies);
522 static void transaction_delete_unit(Manager *m, Unit *u) {
525 /* Deletes all jobs associated with a certain unit from the
528 while ((j = hashmap_get(m->transaction_jobs, u)))
529 transaction_delete_job(m, j, true);
532 static void transaction_clean_dependencies(Manager *m) {
538 /* Drops all dependencies of all installed jobs */
540 HASHMAP_FOREACH(j, m->jobs, i) {
541 while (j->subject_list)
542 job_dependency_free(j->subject_list);
543 while (j->object_list)
544 job_dependency_free(j->object_list);
547 assert(!m->transaction_anchor);
550 static void transaction_abort(Manager *m) {
555 while ((j = hashmap_first(m->transaction_jobs)))
557 transaction_delete_job(m, j, true);
561 assert(hashmap_isempty(m->transaction_jobs));
563 transaction_clean_dependencies(m);
566 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
571 /* A recursive sweep through the graph that marks all units
572 * that matter to the anchor job, i.e. are directly or
573 * indirectly a dependency of the anchor job via paths that
574 * are fully marked as mattering. */
579 l = m->transaction_anchor;
581 LIST_FOREACH(subject, l, l) {
583 /* This link does not matter */
587 /* This unit has already been marked */
588 if (l->object->generation == generation)
591 l->object->matters_to_anchor = true;
592 l->object->generation = generation;
594 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
598 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
599 JobDependency *l, *last;
603 assert(j->unit == other->unit);
604 assert(!j->installed);
606 /* Merges 'other' into 'j' and then deletes j. */
609 j->state = JOB_WAITING;
610 j->override = j->override || other->override;
612 j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
614 /* Patch us in as new owner of the JobDependency objects */
616 LIST_FOREACH(subject, l, other->subject_list) {
617 assert(l->subject == other);
622 /* Merge both lists */
624 last->subject_next = j->subject_list;
626 j->subject_list->subject_prev = last;
627 j->subject_list = other->subject_list;
630 /* Patch us in as new owner of the JobDependency objects */
632 LIST_FOREACH(object, l, other->object_list) {
633 assert(l->object == other);
638 /* Merge both lists */
640 last->object_next = j->object_list;
642 j->object_list->object_prev = last;
643 j->object_list = other->object_list;
646 /* Kill the other job */
647 other->subject_list = NULL;
648 other->object_list = NULL;
649 transaction_delete_job(m, other, true);
652 static int delete_one_unmergeable_job(Manager *m, Job *j) {
657 /* Tries to delete one item in the linked list
658 * j->transaction_next->transaction_next->... that conflicts
659 * whith another one, in an attempt to make an inconsistent
660 * transaction work. */
662 /* We rely here on the fact that if a merged with b does not
663 * merge with c, either a or b merge with c neither */
664 LIST_FOREACH(transaction, j, j)
665 LIST_FOREACH(transaction, k, j->transaction_next) {
668 /* Is this one mergeable? Then skip it */
669 if (job_type_is_mergeable(j->type, k->type))
672 /* Ok, we found two that conflict, let's see if we can
673 * drop one of them */
674 if (!j->matters_to_anchor)
676 else if (!k->matters_to_anchor)
681 /* Ok, we can drop one, so let's do so. */
682 log_debug("Trying to fix job merging by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type));
683 transaction_delete_job(m, d, true);
690 static int transaction_merge_jobs(Manager *m) {
697 /* First step, check whether any of the jobs for one specific
698 * task conflict. If so, try to drop one of them. */
699 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
704 LIST_FOREACH(transaction, k, j->transaction_next) {
705 if ((r = job_type_merge(&t, k->type)) >= 0)
708 /* OK, we could not merge all jobs for this
709 * action. Let's see if we can get rid of one
712 if ((r = delete_one_unmergeable_job(m, j)) >= 0)
713 /* Ok, we managed to drop one, now
714 * let's ask our callers to call us
715 * again after garbage collecting */
718 /* We couldn't merge anything. Failure */
723 /* Second step, merge the jobs. */
724 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
728 /* Merge all transactions */
729 LIST_FOREACH(transaction, k, j->transaction_next)
730 assert_se(job_type_merge(&t, k->type) == 0);
732 /* If an active job is mergeable, merge it too */
733 if (j->unit->meta.job)
734 job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
736 while ((k = j->transaction_next)) {
738 transaction_merge_and_delete_job(m, k, j, t);
741 transaction_merge_and_delete_job(m, j, k, t);
744 assert(!j->transaction_next);
745 assert(!j->transaction_prev);
751 static void transaction_drop_redundant(Manager *m) {
756 /* Goes through the transaction and removes all jobs that are
765 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
766 bool changes_something = false;
769 LIST_FOREACH(transaction, k, j) {
771 if (!job_is_anchor(k) &&
772 job_type_is_redundant(k->type, unit_active_state(k->unit)))
775 changes_something = true;
779 if (changes_something)
782 log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type));
783 transaction_delete_job(m, j, false);
791 static bool unit_matters_to_anchor(Unit *u, Job *j) {
793 assert(!j->transaction_prev);
795 /* Checks whether at least one of the jobs for this unit
796 * matters to the anchor. */
798 LIST_FOREACH(transaction, j, j)
799 if (j->matters_to_anchor)
805 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation) {
812 assert(!j->transaction_prev);
814 /* Does a recursive sweep through the ordering graph, looking
815 * for a cycle. If we find cycle we try to break it. */
817 /* Did we find a cycle? */
818 if (j->marker && j->generation == generation) {
821 /* So, we already have been here. We have a
822 * cycle. Let's try to break it. We go backwards in
823 * our path and try to find a suitable job to
824 * remove. We use the marker to find our way back,
825 * since smart how we are we stored our way back in
828 log_debug("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type));
830 for (k = from; k; k = (k->generation == generation ? k->marker : NULL)) {
832 log_debug("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type));
835 !unit_matters_to_anchor(k->unit, k)) {
836 /* Ok, we can drop this one, so let's
838 log_debug("Breaking order cycle by deleting job %s/%s", k->unit->meta.id, job_type_to_string(k->type));
839 transaction_delete_unit(m, k->unit);
843 /* Check if this in fact was the beginning of
849 log_debug("Unable to break cycle");
854 /* Make the marker point to where we come from, so that we can
855 * find our way backwards if we want to break a cycle */
857 j->generation = generation;
859 /* We assume that the the dependencies are bidirectional, and
860 * hence can ignore UNIT_AFTER */
861 SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
864 /* Is there a job for this unit? */
865 if (!(o = hashmap_get(m->transaction_jobs, u)))
867 /* Ok, there is no job for this in the
868 * transaction, but maybe there is already one
870 if (!(o = u->meta.job))
873 if ((r = transaction_verify_order_one(m, o, j, generation)) < 0)
877 /* Ok, let's backtrack, and remember that this entry is not on
878 * our path anymore. */
884 static int transaction_verify_order(Manager *m, unsigned *generation) {
892 /* Check if the ordering graph is cyclic. If it is, try to fix
893 * that up by dropping one of the jobs. */
895 HASHMAP_FOREACH(j, m->transaction_jobs, i)
896 if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0)
902 static void transaction_collect_garbage(Manager *m) {
907 /* Drop jobs that are not required by any other job */
915 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
919 log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type));
920 transaction_delete_job(m, j, true);
928 static int transaction_is_destructive(Manager *m, JobMode mode) {
934 /* Checks whether applying this transaction means that
935 * existing jobs would be replaced */
937 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
940 assert(!j->transaction_prev);
941 assert(!j->transaction_next);
943 if (j->unit->meta.job &&
944 j->unit->meta.job != j &&
945 !job_type_is_superset(j->type, j->unit->meta.job->type))
952 static void transaction_minimize_impact(Manager *m) {
956 /* Drops all unnecessary jobs that reverse already active jobs
957 * or that stop a running service. */
965 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
966 LIST_FOREACH(transaction, j, j) {
967 bool stops_running_service, changes_existing_job;
969 /* If it matters, we shouldn't drop it */
970 if (j->matters_to_anchor)
973 /* Would this stop a running service?
974 * Would this change an existing job?
975 * If so, let's drop this entry */
977 stops_running_service =
978 j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
980 changes_existing_job =
981 j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->state);
983 if (!stops_running_service && !changes_existing_job)
986 if (stops_running_service)
987 log_debug("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type));
989 if (changes_existing_job)
990 log_debug("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type));
992 /* Ok, let's get rid of this */
993 log_debug("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type));
995 transaction_delete_job(m, j, true);
1007 static int transaction_apply(Manager *m, JobMode mode) {
1012 /* Moves the transaction jobs to the set of active jobs */
1014 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1016 assert(!j->transaction_prev);
1017 assert(!j->transaction_next);
1022 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
1026 while ((j = hashmap_steal_first(m->transaction_jobs))) {
1030 if (j->unit->meta.job)
1031 job_free(j->unit->meta.job);
1033 j->unit->meta.job = j;
1034 j->installed = true;
1036 /* We're fully installed. Now let's free data we don't
1039 assert(!j->transaction_next);
1040 assert(!j->transaction_prev);
1042 job_add_to_run_queue(j);
1043 job_add_to_dbus_queue(j);
1046 /* As last step, kill all remaining job dependencies. */
1047 transaction_clean_dependencies(m);
1053 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
1057 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
1063 static int transaction_activate(Manager *m, JobMode mode) {
1065 unsigned generation = 1;
1069 /* This applies the changes recorded in transaction_jobs to
1070 * the actual list of jobs, if possible. */
1072 /* First step: figure out which jobs matter */
1073 transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
1075 /* Second step: Try not to stop any running services if
1076 * we don't have to. Don't try to reverse running
1077 * jobs if we don't have to. */
1078 transaction_minimize_impact(m);
1080 /* Third step: Drop redundant jobs */
1081 transaction_drop_redundant(m);
1084 /* Fourth step: Let's remove unneeded jobs that might
1086 transaction_collect_garbage(m);
1088 /* Fifth step: verify order makes sense and correct
1089 * cycles if necessary and possible */
1090 if ((r = transaction_verify_order(m, &generation)) >= 0)
1094 log_debug("Requested transaction contains an unfixable cyclic ordering dependency: %s", strerror(-r));
1098 /* Let's see if the resulting transaction ordering
1099 * graph is still cyclic... */
1103 /* Sixth step: let's drop unmergeable entries if
1104 * necessary and possible, merge entries we can
1106 if ((r = transaction_merge_jobs(m)) >= 0)
1110 log_debug("Requested transaction contains unmergable jobs: %s", strerror(-r));
1114 /* Seventh step: an entry got dropped, let's garbage
1115 * collect its dependencies. */
1116 transaction_collect_garbage(m);
1118 /* Let's see if the resulting transaction still has
1119 * unmergeable entries ... */
1122 /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */
1123 transaction_drop_redundant(m);
1125 /* Ninth step: check whether we can actually apply this */
1126 if (mode == JOB_FAIL)
1127 if ((r = transaction_is_destructive(m, mode)) < 0) {
1128 log_debug("Requested transaction contradicts existing jobs: %s", strerror(-r));
1132 /* Tenth step: apply changes */
1133 if ((r = transaction_apply(m, mode)) < 0) {
1134 log_debug("Failed to apply transaction: %s", strerror(-r));
1138 assert(hashmap_isempty(m->transaction_jobs));
1139 assert(!m->transaction_anchor);
1144 transaction_abort(m);
1148 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) {
1155 /* Looks for an axisting prospective job and returns that. If
1156 * it doesn't exist it is created and added to the prospective
1159 f = hashmap_get(m->transaction_jobs, unit);
1161 LIST_FOREACH(transaction, j, f) {
1162 assert(j->unit == unit);
1164 if (j->type == type) {
1171 if (unit->meta.job && unit->meta.job->type == type)
1173 else if (!(j = job_new(m, type, unit)))
1178 j->matters_to_anchor = false;
1179 j->override = override;
1181 LIST_PREPEND(Job, transaction, f, j);
1183 if ((r = hashmap_replace(m->transaction_jobs, unit, f)) < 0) {
1191 log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type));
1196 void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) {
1200 if (j->transaction_prev)
1201 j->transaction_prev->transaction_next = j->transaction_next;
1202 else if (j->transaction_next)
1203 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
1205 hashmap_remove_value(m->transaction_jobs, j->unit, j);
1207 if (j->transaction_next)
1208 j->transaction_next->transaction_prev = j->transaction_prev;
1210 j->transaction_prev = j->transaction_next = NULL;
1212 while (j->subject_list)
1213 job_dependency_free(j->subject_list);
1215 while (j->object_list) {
1216 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
1218 job_dependency_free(j->object_list);
1220 if (other && delete_dependencies) {
1221 log_debug("Deleting job %s/%s as dependency of job %s/%s",
1222 other->unit->meta.id, job_type_to_string(other->type),
1223 j->unit->meta.id, job_type_to_string(j->type));
1224 transaction_delete_job(m, other, delete_dependencies);
1229 static int transaction_add_job_and_dependencies(
1244 assert(type < _JOB_TYPE_MAX);
1247 if (unit->meta.load_state != UNIT_LOADED)
1250 if (!unit_job_is_applicable(unit, type))
1253 /* First add the job. */
1254 if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new)))
1257 /* Then, add a link to the job. */
1258 if (!job_dependency_new(by, ret, matters))
1262 /* Finally, recursively add in all dependencies. */
1263 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
1264 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
1265 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1268 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
1269 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, NULL)) < 0 && r != -EBADR)
1270 log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1272 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
1273 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, NULL)) < 0)
1274 log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1276 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
1277 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1280 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
1281 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, NULL)) < 0 && r != -EBADR)
1282 log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r));
1284 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
1285 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1288 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
1290 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
1291 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, NULL)) < 0 && r != -EBADR)
1295 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
1307 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, Job **_ret) {
1312 assert(type < _JOB_TYPE_MAX);
1314 assert(mode < _JOB_MODE_MAX);
1316 log_debug("Trying to enqueue job %s/%s", unit->meta.id, job_type_to_string(type));
1318 if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, &ret)) < 0) {
1319 transaction_abort(m);
1323 if ((r = transaction_activate(m, mode)) < 0)
1326 log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id);
1334 int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, Job **_ret) {
1339 assert(type < _JOB_TYPE_MAX);
1341 assert(mode < _JOB_MODE_MAX);
1343 if ((r = manager_load_unit(m, name, NULL, &unit)) < 0)
1346 return manager_add_job(m, type, unit, mode, override, _ret);
1349 Job *manager_get_job(Manager *m, uint32_t id) {
1352 return hashmap_get(m->jobs, UINT32_TO_PTR(id));
1355 Unit *manager_get_unit(Manager *m, const char *name) {
1359 return hashmap_get(m->units, name);
1362 unsigned manager_dispatch_load_queue(Manager *m) {
1368 /* Make sure we are not run recursively */
1369 if (m->dispatching_load_queue)
1372 m->dispatching_load_queue = true;
1374 /* Dispatches the load queue. Takes a unit from the queue and
1375 * tries to load its data until the queue is empty */
1377 while ((meta = m->load_queue)) {
1378 assert(meta->in_load_queue);
1380 unit_load(UNIT(meta));
1384 m->dispatching_load_queue = false;
1388 int manager_load_unit(Manager *m, const char *name, const char *path, Unit **_ret) {
1393 assert(name || path);
1395 /* This will load the service information files, but not actually
1396 * start any services or anything. */
1398 if (path && !is_path(path))
1402 name = file_name_from_path(path);
1404 if (!unit_name_is_valid(name))
1407 if ((ret = manager_get_unit(m, name))) {
1412 if (!(ret = unit_new(m)))
1416 if (!(ret->meta.fragment_path = strdup(path))) {
1421 if ((r = unit_add_name(ret, name)) < 0) {
1426 unit_add_to_load_queue(ret);
1427 unit_add_to_dbus_queue(ret);
1429 manager_dispatch_load_queue(m);
1432 *_ret = unit_follow_merge(ret);
1437 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1444 HASHMAP_FOREACH(j, s->jobs, i)
1445 job_dump(j, f, prefix);
1448 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1456 HASHMAP_FOREACH_KEY(u, t, s->units, i)
1457 if (u->meta.id == t)
1458 unit_dump(u, f, prefix);
1461 void manager_clear_jobs(Manager *m) {
1466 transaction_abort(m);
1468 while ((j = hashmap_first(m->jobs)))
1472 unsigned manager_dispatch_run_queue(Manager *m) {
1476 if (m->dispatching_run_queue)
1479 m->dispatching_run_queue = true;
1481 while ((j = m->run_queue)) {
1482 assert(j->installed);
1483 assert(j->in_run_queue);
1485 job_run_and_invalidate(j);
1489 m->dispatching_run_queue = false;
1493 unsigned manager_dispatch_dbus_queue(Manager *m) {
1500 if (m->dispatching_dbus_queue)
1503 m->dispatching_dbus_queue = true;
1505 while ((meta = m->dbus_unit_queue)) {
1506 assert(meta->in_dbus_queue);
1508 bus_unit_send_change_signal(UNIT(meta));
1512 while ((j = m->dbus_job_queue)) {
1513 assert(j->in_dbus_queue);
1515 bus_job_send_change_signal(j);
1519 m->dispatching_dbus_queue = false;
1523 static int manager_dispatch_sigchld(Manager *m) {
1532 /* First we call waitd() for a PID and do not reap the
1533 * zombie. That way we can still access /proc/$PID for
1534 * it while it is a zombie. */
1535 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) {
1537 if (errno == ECHILD)
1549 if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) {
1552 get_process_name(si.si_pid, &name);
1553 log_debug("Got SIGCHLD for process %llu (%s)", (unsigned long long) si.si_pid, strna(name));
1557 /* And now, we actually reap the zombie. */
1558 if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) {
1565 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1568 log_debug("Child %llu died (code=%s, status=%i/%s)",
1569 (long long unsigned) si.si_pid,
1570 sigchld_code_to_string(si.si_code),
1572 strna(si.si_code == CLD_EXITED ? exit_status_to_string(si.si_status) : strsignal(si.si_status)));
1574 if (!(u = hashmap_remove(m->watch_pids, UINT32_TO_PTR(si.si_pid))))
1577 log_debug("Child %llu belongs to %s", (long long unsigned) si.si_pid, u->meta.id);
1579 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1585 static void manager_start_target(Manager *m, const char *name) {
1588 if ((r = manager_add_job_by_name(m, JOB_START, name, JOB_REPLACE, true, NULL)) < 0)
1589 log_error("Failed to enqueue %s job: %s", name, strerror(-r));
1592 static int manager_process_signal_fd(Manager *m) {
1594 struct signalfd_siginfo sfsi;
1595 bool sigchld = false;
1600 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1605 if (errno == EAGAIN)
1611 switch (sfsi.ssi_signo) {
1620 if (m->running_as == MANAGER_INIT) {
1621 manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET);
1625 m->exit_code = MANAGER_EXIT;
1630 if (m->running_as == MANAGER_INIT)
1631 manager_start_target(m, SPECIAL_KBREQUEST_TARGET);
1633 /* This is a nop on non-init */
1637 if (m->running_as == MANAGER_INIT)
1638 manager_start_target(m, SPECIAL_SIGPWR_TARGET);
1640 /* This is a nop on non-init */
1644 manager_dump_units(m, stdout, "\t");
1645 manager_dump_jobs(m, stdout, "\t");
1651 u = manager_get_unit(m, SPECIAL_DBUS_SERVICE);
1653 if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) {
1654 log_info("Trying to reconnect to bus...");
1659 if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) {
1660 log_info("Loading D-Bus service...");
1661 manager_start_target(m, SPECIAL_DBUS_SERVICE);
1668 m->exit_code = MANAGER_RELOAD;
1672 log_info("Got unhandled signal <%s>.", strsignal(sfsi.ssi_signo));
1677 return manager_dispatch_sigchld(m);
1682 static int process_event(Manager *m, struct epoll_event *ev) {
1689 assert(w = ev->data.ptr);
1695 /* An incoming signal? */
1696 if (ev->events != EPOLLIN)
1699 if ((r = manager_process_signal_fd(m)) < 0)
1706 /* Some fd event, to be dispatched to the units */
1707 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
1714 /* Some timer event, to be dispatched to the units */
1715 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
1717 if (k < 0 && (errno == EINTR || errno == EAGAIN))
1720 return k < 0 ? -errno : -EIO;
1723 UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
1728 /* Some mount table change, intended for the mount subsystem */
1729 mount_fd_event(m, ev->events);
1733 /* Some notification from udev, intended for the device subsystem */
1734 device_fd_event(m, ev->events);
1737 case WATCH_DBUS_WATCH:
1738 bus_watch_event(m, w, ev->events);
1741 case WATCH_DBUS_TIMEOUT:
1742 bus_timeout_event(m, w, ev->events);
1746 assert_not_reached("Unknown epoll event type.");
1752 int manager_loop(Manager *m) {
1755 RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
1758 m->exit_code = MANAGER_RUNNING;
1760 while (m->exit_code == MANAGER_RUNNING) {
1761 struct epoll_event event;
1764 if (!ratelimit_test(&rl)) {
1765 /* Yay, something is going seriously wrong, pause a little */
1766 log_warning("Looping too fast. Throttling execution a little.");
1770 if (manager_dispatch_cleanup_queue(m) > 0)
1773 if (manager_dispatch_load_queue(m) > 0)
1776 if (manager_dispatch_run_queue(m) > 0)
1779 if (bus_dispatch(m) > 0)
1782 if (manager_dispatch_dbus_queue(m) > 0)
1785 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
1787 if (errno == -EINTR)
1795 if ((r = process_event(m, &event)) < 0)
1799 return m->exit_code;
1802 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
1810 if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
1813 if (!(n = bus_path_unescape(s+31)))
1816 u = manager_get_unit(m, n);
1827 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
1836 if (!startswith(s, "/org/freedesktop/systemd1/job/"))
1839 if ((r = safe_atou(s + 30, &id)) < 0)
1842 if (!(j = manager_get_job(m, id)))
1850 static bool manager_utmp_good(Manager *m) {
1855 if ((r = mount_path_is_mounted(m, _PATH_UTMPX)) <= 0) {
1858 log_warning("Failed to determine whether " _PATH_UTMPX " is mounted: %s", strerror(-r));
1866 void manager_write_utmp_reboot(Manager *m) {
1871 if (m->utmp_reboot_written)
1874 if (m->running_as != MANAGER_INIT)
1877 if (!manager_utmp_good(m))
1880 if ((r = utmp_put_reboot(m->boot_timestamp)) < 0) {
1882 if (r != -ENOENT && r != -EROFS)
1883 log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
1888 m->utmp_reboot_written = true;
1891 void manager_write_utmp_runlevel(Manager *m, Unit *u) {
1897 if (u->meta.type != UNIT_TARGET)
1900 if (m->running_as != MANAGER_INIT)
1903 if (!manager_utmp_good(m))
1906 if ((runlevel = target_get_runlevel(TARGET(u))) <= 0)
1909 if ((r = utmp_put_runlevel(0, runlevel, 0)) < 0) {
1911 if (r != -ENOENT && r != -EROFS)
1912 log_warning("Failed to write utmp/wtmp: %s", strerror(-r));
1916 void manager_dispatch_bus_name_owner_changed(
1919 const char* old_owner,
1920 const char *new_owner) {
1927 if (!(u = hashmap_get(m->watch_bus, name)))
1930 UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner);
1933 void manager_dispatch_bus_query_pid_done(
1944 if (!(u = hashmap_get(m->watch_bus, name)))
1947 UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid);
1950 int manager_open_serialization(FILE **_f) {
1958 if (asprintf(&path, "/dev/shm/systemd-%u.dump-XXXXXX", (unsigned) getpid()) < 0)
1961 saved_umask = umask(0077);
1962 fd = mkostemp(path, O_RDWR|O_CLOEXEC);
1972 log_debug("Serializing state to %s", path);
1975 if (!(f = fdopen(fd, "w+")) < 0)
1983 int manager_serialize(Manager *m, FILE *f, FDSet *fds) {
1993 HASHMAP_FOREACH_KEY(u, t, m->units, i) {
1994 if (u->meta.id != t)
1997 if (!unit_can_serialize(u))
2001 fputs(u->meta.id, f);
2004 if ((r = unit_serialize(u, f, fds)) < 0)
2014 int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
2020 log_debug("Deserializing state...");
2024 char name[UNIT_NAME_MAX+2];
2027 if (!fgets(name, sizeof(name), f)) {
2036 if ((r = manager_load_unit(m, strstrip(name), NULL, &u)) < 0)
2039 if ((r = unit_deserialize(u, f, fds)) < 0)
2049 int manager_reload(Manager *m) {
2056 if ((r = manager_open_serialization(&f)) < 0)
2059 if (!(fds = fdset_new())) {
2064 if ((r = manager_serialize(m, f, fds)) < 0)
2067 if (fseeko(f, 0, SEEK_SET) < 0) {
2072 /* From here on there is no way back. */
2073 manager_clear_jobs_and_units(m);
2075 /* First, enumerate what we can from all config files */
2076 if ((q = manager_enumerate(m)) < 0)
2079 /* Second, deserialize our stored data */
2080 if ((q = manager_deserialize(m, f, fds)) < 0)
2086 /* Third, fire things up! */
2087 if ((q = manager_coldplug(m)) < 0)
2100 static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = {
2101 [MANAGER_INIT] = "init",
2102 [MANAGER_SYSTEM] = "system",
2103 [MANAGER_SESSION] = "session"
2106 DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);