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>
38 #include "ratelimit.h"
40 static int manager_setup_signals(Manager *m) {
42 struct epoll_event ev;
46 assert_se(reset_all_signal_handlers() == 0);
48 assert_se(sigemptyset(&mask) == 0);
49 assert_se(sigaddset(&mask, SIGCHLD) == 0);
50 assert_se(sigaddset(&mask, SIGINT) == 0); /* Kernel sends us this on control-alt-del */
51 assert_se(sigaddset(&mask, SIGWINCH) == 0); /* Kernel sends us this on kbrequest (alt-arrowup) */
52 assert_se(sigaddset(&mask, SIGTERM) == 0);
53 assert_se(sigaddset(&mask, SIGHUP) == 0);
54 assert_se(sigaddset(&mask, SIGUSR1) == 0);
55 assert_se(sigaddset(&mask, SIGUSR2) == 0);
56 assert_se(sigaddset(&mask, SIGPIPE) == 0);
57 assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
59 m->signal_watch.type = WATCH_SIGNAL;
60 if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0)
65 ev.data.ptr = &m->signal_watch;
67 if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0)
73 Manager* manager_new(void) {
76 if (!(m = new0(Manager, 1)))
79 m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = -1;
80 m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */
82 if (!(m->units = hashmap_new(string_hash_func, string_compare_func)))
85 if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
88 if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
91 if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
94 if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
97 if (manager_setup_signals(m) < 0)
100 /* FIXME: this should be called only when the D-Bus bus daemon is running */
111 void manager_free(Manager *m) {
118 while ((j = hashmap_first(m->transaction_jobs)))
121 while ((u = hashmap_first(m->units)))
124 for (c = 0; c < _UNIT_TYPE_MAX; c++)
125 if (unit_vtable[c]->shutdown)
126 unit_vtable[c]->shutdown(m);
130 hashmap_free(m->units);
131 hashmap_free(m->jobs);
132 hashmap_free(m->transaction_jobs);
133 hashmap_free(m->watch_pids);
135 if (m->epoll_fd >= 0)
136 close_nointr(m->epoll_fd);
137 if (m->signal_watch.fd >= 0)
138 close_nointr(m->signal_watch.fd);
143 int manager_coldplug(Manager *m) {
152 /* First, let's ask every type to load all units from
153 * disk/kernel that it might know */
154 for (c = 0; c < _UNIT_TYPE_MAX; c++)
155 if (unit_vtable[c]->enumerate)
156 if ((r = unit_vtable[c]->enumerate(m)) < 0)
159 manager_dispatch_load_queue(m);
161 /* Then, let's set up their initial state. */
162 HASHMAP_FOREACH_KEY(u, k, m->units, i) {
168 if (UNIT_VTABLE(u)->coldplug)
169 if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
176 static void transaction_delete_job(Manager *m, Job *j) {
180 /* Deletes one job from the transaction */
182 manager_transaction_unlink_job(m, j);
188 static void transaction_delete_unit(Manager *m, Unit *u) {
191 /* Deletes all jobs associated with a certain unit from the
194 while ((j = hashmap_get(m->transaction_jobs, u)))
195 transaction_delete_job(m, j);
198 static void transaction_clean_dependencies(Manager *m) {
204 /* Drops all dependencies of all installed jobs */
206 HASHMAP_FOREACH(j, m->jobs, i) {
207 while (j->subject_list)
208 job_dependency_free(j->subject_list);
209 while (j->object_list)
210 job_dependency_free(j->object_list);
213 assert(!m->transaction_anchor);
216 static void transaction_abort(Manager *m) {
221 while ((j = hashmap_first(m->transaction_jobs)))
223 transaction_delete_job(m, j);
227 assert(hashmap_isempty(m->transaction_jobs));
229 transaction_clean_dependencies(m);
232 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
237 /* A recursive sweep through the graph that marks all units
238 * that matter to the anchor job, i.e. are directly or
239 * indirectly a dependency of the anchor job via paths that
240 * are fully marked as mattering. */
245 l = m->transaction_anchor;
247 LIST_FOREACH(subject, l, l) {
249 /* This link does not matter */
253 /* This unit has already been marked */
254 if (l->object->generation == generation)
257 l->object->matters_to_anchor = true;
258 l->object->generation = generation;
260 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
264 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
265 JobDependency *l, *last;
269 assert(j->unit == other->unit);
270 assert(!j->installed);
272 /* Merges 'other' into 'j' and then deletes j. */
275 j->state = JOB_WAITING;
276 j->forced = j->forced || other->forced;
278 j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
280 /* Patch us in as new owner of the JobDependency objects */
282 LIST_FOREACH(subject, l, other->subject_list) {
283 assert(l->subject == other);
288 /* Merge both lists */
290 last->subject_next = j->subject_list;
292 j->subject_list->subject_prev = last;
293 j->subject_list = other->subject_list;
296 /* Patch us in as new owner of the JobDependency objects */
298 LIST_FOREACH(object, l, other->object_list) {
299 assert(l->object == other);
304 /* Merge both lists */
306 last->object_next = j->object_list;
308 j->object_list->object_prev = last;
309 j->object_list = other->object_list;
312 /* Kill the other job */
313 other->subject_list = NULL;
314 other->object_list = NULL;
315 transaction_delete_job(m, other);
318 static int delete_one_unmergeable_job(Manager *m, Job *j) {
323 /* Tries to delete one item in the linked list
324 * j->transaction_next->transaction_next->... that conflicts
325 * whith another one, in an attempt to make an inconsistent
326 * transaction work. */
328 /* We rely here on the fact that if a merged with b does not
329 * merge with c, either a or b merge with c neither */
330 LIST_FOREACH(transaction, j, j)
331 LIST_FOREACH(transaction, k, j->transaction_next) {
334 /* Is this one mergeable? Then skip it */
335 if (job_type_is_mergeable(j->type, k->type))
338 /* Ok, we found two that conflict, let's see if we can
339 * drop one of them */
340 if (!j->matters_to_anchor)
342 else if (!k->matters_to_anchor)
347 /* Ok, we can drop one, so let's do so. */
348 log_debug("Try to fix job merging by deleting job %s/%s", unit_id(d->unit), job_type_to_string(d->type));
349 transaction_delete_job(m, d);
356 static int transaction_merge_jobs(Manager *m) {
363 /* First step, check whether any of the jobs for one specific
364 * task conflict. If so, try to drop one of them. */
365 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
370 LIST_FOREACH(transaction, k, j->transaction_next) {
371 if ((r = job_type_merge(&t, k->type)) >= 0)
374 /* OK, we could not merge all jobs for this
375 * action. Let's see if we can get rid of one
378 if ((r = delete_one_unmergeable_job(m, j)) >= 0)
379 /* Ok, we managed to drop one, now
380 * let's ask our callers to call us
381 * again after garbage collecting */
384 /* We couldn't merge anything. Failure */
389 /* Second step, merge the jobs. */
390 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
394 /* Merge all transactions */
395 LIST_FOREACH(transaction, k, j->transaction_next)
396 assert_se(job_type_merge(&t, k->type) == 0);
398 /* If an active job is mergeable, merge it too */
399 if (j->unit->meta.job)
400 job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */
402 while ((k = j->transaction_next)) {
404 transaction_merge_and_delete_job(m, k, j, t);
407 transaction_merge_and_delete_job(m, j, k, t);
410 assert(!j->transaction_next);
411 assert(!j->transaction_prev);
417 static bool unit_matters_to_anchor(Unit *u, Job *j) {
419 assert(!j->transaction_prev);
421 /* Checks whether at least one of the jobs for this unit
422 * matters to the anchor. */
424 LIST_FOREACH(transaction, j, j)
425 if (j->matters_to_anchor)
431 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation) {
438 assert(!j->transaction_prev);
440 /* Does a recursive sweep through the ordering graph, looking
441 * for a cycle. If we find cycle we try to break it. */
443 /* Did we find a cycle? */
444 if (j->marker && j->generation == generation) {
447 /* So, we already have been here. We have a
448 * cycle. Let's try to break it. We go backwards in
449 * our path and try to find a suitable job to
450 * remove. We use the marker to find our way back,
451 * since smart how we are we stored our way back in
454 log_debug("Found cycle on %s/%s", unit_id(j->unit), job_type_to_string(j->type));
456 for (k = from; k; k = (k->generation == generation ? k->marker : NULL)) {
458 log_debug("Walked on cycle path to %s/%s", unit_id(j->unit), job_type_to_string(j->type));
461 !unit_matters_to_anchor(k->unit, k)) {
462 /* Ok, we can drop this one, so let's
464 log_debug("Breaking order cycle by deleting job %s/%s", unit_id(k->unit), job_type_to_string(k->type));
465 transaction_delete_unit(m, k->unit);
469 /* Check if this in fact was the beginning of
475 log_debug("Unable to break cycle");
480 /* Make the marker point to where we come from, so that we can
481 * find our way backwards if we want to break a cycle */
483 j->generation = generation;
485 /* We assume that the the dependencies are bidirectional, and
486 * hence can ignore UNIT_AFTER */
487 SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) {
490 /* Is there a job for this unit? */
491 if (!(o = hashmap_get(m->transaction_jobs, u)))
493 /* Ok, there is no job for this in the
494 * transaction, but maybe there is already one
496 if (!(o = u->meta.job))
499 if ((r = transaction_verify_order_one(m, o, j, generation)) < 0)
503 /* Ok, let's backtrack, and remember that this entry is not on
504 * our path anymore. */
510 static int transaction_verify_order(Manager *m, unsigned *generation) {
518 /* Check if the ordering graph is cyclic. If it is, try to fix
519 * that up by dropping one of the jobs. */
521 HASHMAP_FOREACH(j, m->transaction_jobs, i)
522 if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0)
528 static void transaction_collect_garbage(Manager *m) {
533 /* Drop jobs that are not required by any other job */
541 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
545 log_debug("Garbage collecting job %s/%s", unit_id(j->unit), job_type_to_string(j->type));
546 transaction_delete_job(m, j);
554 static int transaction_is_destructive(Manager *m, JobMode mode) {
560 /* Checks whether applying this transaction means that
561 * existing jobs would be replaced */
563 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
566 assert(!j->transaction_prev);
567 assert(!j->transaction_next);
569 if (j->unit->meta.job &&
570 j->unit->meta.job != j &&
571 !job_type_is_superset(j->type, j->unit->meta.job->type))
578 static void transaction_minimize_impact(Manager *m) {
582 /* Drops all unnecessary jobs that reverse already active jobs
583 * or that stop a running service. */
591 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
592 LIST_FOREACH(transaction, j, j) {
593 bool stops_running_service, changes_existing_job;
595 /* If it matters, we shouldn't drop it */
596 if (j->matters_to_anchor)
599 /* Would this stop a running service?
600 * Would this change an existing job?
601 * If so, let's drop this entry */
603 stops_running_service =
604 j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit));
606 changes_existing_job =
607 j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->state);
609 if (!stops_running_service && !changes_existing_job)
612 if (stops_running_service)
613 log_debug("%s/%s would stop a running service.", unit_id(j->unit), job_type_to_string(j->type));
615 if (changes_existing_job)
616 log_debug("%s/%s would change existing job.", unit_id(j->unit), job_type_to_string(j->type));
618 /* Ok, let's get rid of this */
619 log_debug("Deleting %s/%s to minimize impact.", unit_id(j->unit), job_type_to_string(j->type));
621 transaction_delete_job(m, j);
633 static int transaction_apply(Manager *m, JobMode mode) {
638 /* Moves the transaction jobs to the set of active jobs */
640 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
642 assert(!j->transaction_prev);
643 assert(!j->transaction_next);
648 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
652 while ((j = hashmap_steal_first(m->transaction_jobs))) {
656 if (j->unit->meta.job)
657 job_free(j->unit->meta.job);
659 j->unit->meta.job = j;
662 /* We're fully installed. Now let's free data we don't
665 assert(!j->transaction_next);
666 assert(!j->transaction_prev);
668 job_add_to_run_queue(j);
669 job_add_to_dbus_queue(j);
672 /* As last step, kill all remaining job dependencies. */
673 transaction_clean_dependencies(m);
679 HASHMAP_FOREACH(j, m->transaction_jobs, i) {
683 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
689 static int transaction_activate(Manager *m, JobMode mode) {
691 unsigned generation = 1;
695 /* This applies the changes recorded in transaction_jobs to
696 * the actual list of jobs, if possible. */
698 /* First step: figure out which jobs matter */
699 transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
701 /* Second step: Try not to stop any running services if
702 * we don't have to. Don't try to reverse running
703 * jobs if we don't have to. */
704 transaction_minimize_impact(m);
707 /* Third step: Let's remove unneeded jobs that might
709 transaction_collect_garbage(m);
711 /* Fourth step: verify order makes sense and correct
712 * cycles if necessary and possible */
713 if ((r = transaction_verify_order(m, &generation)) >= 0)
717 log_debug("Requested transaction contains an unfixable cyclic ordering dependency: %s", strerror(-r));
721 /* Let's see if the resulting transaction ordering
722 * graph is still cyclic... */
726 /* Fifth step: let's drop unmergeable entries if
727 * necessary and possible, merge entries we can
729 if ((r = transaction_merge_jobs(m)) >= 0)
733 log_debug("Requested transaction contains unmergable jobs: %s", strerror(-r));
737 /* Sixth step: an entry got dropped, let's garbage
738 * collect its dependencies. */
739 transaction_collect_garbage(m);
741 /* Let's see if the resulting transaction still has
742 * unmergeable entries ... */
745 /* Seventh step: check whether we can actually apply this */
746 if (mode == JOB_FAIL)
747 if ((r = transaction_is_destructive(m, mode)) < 0) {
748 log_debug("Requested transaction contradicts existing jobs: %s", strerror(-r));
752 /* Eights step: apply changes */
753 if ((r = transaction_apply(m, mode)) < 0) {
754 log_debug("Failed to apply transaction: %s", strerror(-r));
758 assert(hashmap_isempty(m->transaction_jobs));
759 assert(!m->transaction_anchor);
764 transaction_abort(m);
768 static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool force, bool *is_new) {
775 /* Looks for an axisting prospective job and returns that. If
776 * it doesn't exist it is created and added to the prospective
779 f = hashmap_get(m->transaction_jobs, unit);
781 LIST_FOREACH(transaction, j, f) {
782 assert(j->unit == unit);
784 if (j->type == type) {
791 if (unit->meta.job && unit->meta.job->type == type)
793 else if (!(j = job_new(m, type, unit)))
798 j->matters_to_anchor = false;
801 LIST_PREPEND(Job, transaction, f, j);
803 if ((r = hashmap_replace(m->transaction_jobs, unit, f)) < 0) {
814 void manager_transaction_unlink_job(Manager *m, Job *j) {
818 if (j->transaction_prev)
819 j->transaction_prev->transaction_next = j->transaction_next;
820 else if (j->transaction_next)
821 hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next);
823 hashmap_remove_value(m->transaction_jobs, j->unit, j);
825 if (j->transaction_next)
826 j->transaction_next->transaction_prev = j->transaction_prev;
828 j->transaction_prev = j->transaction_next = NULL;
830 while (j->subject_list)
831 job_dependency_free(j->subject_list);
833 while (j->object_list) {
834 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
836 job_dependency_free(j->object_list);
839 log_debug("Deleting job %s/%s as dependency of job %s/%s",
840 unit_id(other->unit), job_type_to_string(other->type),
841 unit_id(j->unit), job_type_to_string(j->type));
842 transaction_delete_job(m, other);
847 static int transaction_add_job_and_dependencies(Manager *m, JobType type, Unit *unit, Job *by, bool matters, bool force, Job **_ret) {
855 assert(type < _JOB_TYPE_MAX);
858 if (unit->meta.load_state != UNIT_LOADED)
861 if (!unit_job_is_applicable(unit, type))
864 /* First add the job. */
865 if (!(ret = transaction_add_one_job(m, type, unit, force, &is_new)))
868 /* Then, add a link to the job. */
869 if (!job_dependency_new(by, ret, matters))
873 /* Finally, recursively add in all dependencies. */
874 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
875 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i)
876 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, force, NULL)) < 0 && r != -EBADR)
878 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_SOFT_REQUIRES], i)
879 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !force, force, NULL)) < 0 && r != -EBADR)
881 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
882 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, force, NULL)) < 0 && r != -EBADR)
884 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
885 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, force, NULL)) < 0 && r != -EBADR)
887 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_SOFT_REQUISITE], i)
888 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !force, force, NULL)) < 0 && r != -EBADR)
890 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
891 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, force, NULL)) < 0 && r != -EBADR)
894 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
896 SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i)
897 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, force, NULL)) < 0 && r != -EBADR)
901 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
910 int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool force, Job **_ret) {
915 assert(type < _JOB_TYPE_MAX);
917 assert(mode < _JOB_MODE_MAX);
919 log_debug("Trying to enqueue job %s/%s", unit_id(unit), job_type_to_string(type));
921 if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, force, &ret))) {
922 transaction_abort(m);
926 if ((r = transaction_activate(m, mode)) < 0)
929 log_debug("Enqueued job %s/%s", unit_id(unit), job_type_to_string(type));
937 Job *manager_get_job(Manager *m, uint32_t id) {
940 return hashmap_get(m->jobs, UINT32_TO_PTR(id));
943 Unit *manager_get_unit(Manager *m, const char *name) {
947 return hashmap_get(m->units, name);
950 unsigned manager_dispatch_load_queue(Manager *m) {
956 /* Make sure we are not run recursively */
957 if (m->dispatching_load_queue)
960 m->dispatching_load_queue = true;
962 /* Dispatches the load queue. Takes a unit from the queue and
963 * tries to load its data until the queue is empty */
965 while ((meta = m->load_queue)) {
966 assert(meta->in_load_queue);
968 unit_load(UNIT(meta));
972 m->dispatching_load_queue = false;
976 int manager_load_unit(Manager *m, const char *path, Unit **_ret) {
985 /* This will load the service information files, but not actually
986 * start any services or anything. */
988 name = file_name_from_path(path);
990 if ((ret = manager_get_unit(m, name))) {
995 if (!(ret = unit_new(m)))
999 if (!(ret->meta.load_path = strdup(path))) {
1005 if ((r = unit_add_name(ret, name)) < 0) {
1010 unit_add_to_load_queue(ret);
1011 unit_add_to_dbus_queue(ret);
1013 manager_dispatch_load_queue(m);
1019 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
1026 HASHMAP_FOREACH(j, s->jobs, i)
1027 job_dump(j, f, prefix);
1030 void manager_dump_units(Manager *s, FILE *f, const char *prefix) {
1038 HASHMAP_FOREACH_KEY(u, t, s->units, i)
1039 if (unit_id(u) == t)
1040 unit_dump(u, f, prefix);
1043 void manager_clear_jobs(Manager *m) {
1048 transaction_abort(m);
1050 while ((j = hashmap_first(m->jobs)))
1054 unsigned manager_dispatch_run_queue(Manager *m) {
1058 if (m->dispatching_run_queue)
1061 m->dispatching_run_queue = true;
1063 while ((j = m->run_queue)) {
1064 assert(j->installed);
1065 assert(j->in_run_queue);
1067 job_run_and_invalidate(j);
1071 m->dispatching_run_queue = false;
1075 unsigned manager_dispatch_dbus_queue(Manager *m) {
1082 if (m->dispatching_dbus_queue)
1085 m->dispatching_dbus_queue = true;
1087 while ((meta = m->dbus_unit_queue)) {
1088 Unit *u = (Unit*) meta;
1089 assert(u->meta.in_dbus_queue);
1091 bus_unit_send_change_signal(u);
1095 while ((j = m->dbus_job_queue)) {
1096 assert(j->in_dbus_queue);
1098 bus_job_send_change_signal(j);
1102 m->dispatching_dbus_queue = false;
1106 static int manager_dispatch_sigchld(Manager *m) {
1109 log_debug("dispatching SIGCHLD");
1116 if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG) < 0) {
1118 if (errno == ECHILD)
1127 if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED)
1130 log_debug("child %llu died (code=%s, status=%i)", (long long unsigned) si.si_pid, sigchld_code_to_string(si.si_code), si.si_status);
1132 if (!(u = hashmap_remove(m->watch_pids, UINT32_TO_PTR(si.si_pid))))
1135 UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
1141 static int manager_process_signal_fd(Manager *m, bool *quit) {
1143 struct signalfd_siginfo sfsi;
1144 bool sigchld = false;
1149 if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) {
1154 if (errno == EAGAIN)
1160 switch (sfsi.ssi_signo) {
1172 log_info("Got unhandled signal <%s>.", strsignal(sfsi.ssi_signo));
1177 return manager_dispatch_sigchld(m);
1182 static int process_event(Manager *m, struct epoll_event *ev, bool *quit) {
1189 assert(w = ev->data.ptr);
1195 /* An incoming signal? */
1196 if (ev->events != EPOLLIN)
1199 if ((r = manager_process_signal_fd(m, quit)) < 0)
1206 /* Some fd event, to be dispatched to the units */
1207 UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w);
1214 /* Some timer event, to be dispatched to the units */
1215 if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) {
1217 if (k < 0 && (errno == EINTR || errno == EAGAIN))
1220 return k < 0 ? -errno : -EIO;
1223 UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w);
1228 /* Some mount table change, intended for the mount subsystem */
1229 mount_fd_event(m, ev->events);
1233 /* Some notification from udev, intended for the device subsystem */
1234 device_fd_event(m, ev->events);
1237 case WATCH_DBUS_WATCH:
1238 bus_watch_event(m, w, ev->events);
1241 case WATCH_DBUS_TIMEOUT:
1242 bus_timeout_event(m, w, ev->events);
1246 assert_not_reached("Unknown epoll event type.");
1252 int manager_loop(Manager *m) {
1256 RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000);
1261 struct epoll_event event;
1264 if (!ratelimit_test(&rl)) {
1265 /* Yay, something is going seriously wrong, pause a little */
1266 log_warning("Looping too fast. Throttling execution a little.");
1270 if (manager_dispatch_load_queue(m) > 0)
1273 if (manager_dispatch_run_queue(m) > 0)
1276 if (bus_dispatch(m) > 0)
1279 if (manager_dispatch_dbus_queue(m) > 0)
1282 if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) {
1284 if (errno == -EINTR)
1292 if ((r = process_event(m, &event, &quit)) < 0)
1300 int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) {
1308 if (!startswith(s, "/org/freedesktop/systemd1/unit/"))
1311 if (!(n = bus_path_unescape(s+31)))
1314 u = manager_get_unit(m, n);
1325 int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) {
1334 if (!startswith(s, "/org/freedesktop/systemd1/job/"))
1337 if ((r = safe_atou(s + 30, &id)) < 0)
1340 if (!(j = manager_get_job(m, id)))