summaryrefslogtreecommitdiff
path: root/src/job.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/job.c')
-rw-r--r--src/job.c589
1 files changed, 589 insertions, 0 deletions
diff --git a/src/job.c b/src/job.c
new file mode 100644
index 000000000..887de92ca
--- /dev/null
+++ b/src/job.c
@@ -0,0 +1,589 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <assert.h>
+#include <errno.h>
+
+#include "set.h"
+#include "unit.h"
+#include "macro.h"
+#include "strv.h"
+#include "load-fragment.h"
+#include "load-dropin.h"
+#include "log.h"
+#include "dbus-job.h"
+
+Job* job_new(Manager *m, JobType type, Unit *unit) {
+ Job *j;
+
+ assert(m);
+ assert(type < _JOB_TYPE_MAX);
+ assert(unit);
+
+ if (!(j = new0(Job, 1)))
+ return NULL;
+
+ j->manager = m;
+ j->id = m->current_job_id++;
+ j->type = type;
+ j->unit = unit;
+
+ /* We don't link it here, that's what job_dependency() is for */
+
+ return j;
+}
+
+void job_free(Job *j) {
+ assert(j);
+
+ /* Detach from next 'bigger' objects */
+ if (j->installed) {
+ bus_job_send_removed_signal(j);
+
+ if (j->unit->meta.job == j) {
+ j->unit->meta.job = NULL;
+ unit_add_to_gc_queue(j->unit);
+ }
+
+ hashmap_remove(j->manager->jobs, UINT32_TO_PTR(j->id));
+ j->installed = false;
+ }
+
+ /* Detach from next 'smaller' objects */
+ manager_transaction_unlink_job(j->manager, j, true);
+
+ if (j->in_run_queue)
+ LIST_REMOVE(Job, run_queue, j->manager->run_queue, j);
+
+ if (j->in_dbus_queue)
+ LIST_REMOVE(Job, dbus_queue, j->manager->dbus_job_queue, j);
+
+ free(j);
+}
+
+JobDependency* job_dependency_new(Job *subject, Job *object, bool matters) {
+ JobDependency *l;
+
+ assert(object);
+
+ /* Adds a new job link, which encodes that the 'subject' job
+ * needs the 'object' job in some way. If 'subject' is NULL
+ * this means the 'anchor' job (i.e. the one the user
+ * explcitily asked for) is the requester. */
+
+ if (!(l = new0(JobDependency, 1)))
+ return NULL;
+
+ l->subject = subject;
+ l->object = object;
+ l->matters = matters;
+
+ if (subject)
+ LIST_PREPEND(JobDependency, subject, subject->subject_list, l);
+ else
+ LIST_PREPEND(JobDependency, subject, object->manager->transaction_anchor, l);
+
+ LIST_PREPEND(JobDependency, object, object->object_list, l);
+
+ return l;
+}
+
+void job_dependency_free(JobDependency *l) {
+ assert(l);
+
+ if (l->subject)
+ LIST_REMOVE(JobDependency, subject, l->subject->subject_list, l);
+ else
+ LIST_REMOVE(JobDependency, subject, l->object->manager->transaction_anchor, l);
+
+ LIST_REMOVE(JobDependency, object, l->object->object_list, l);
+
+ free(l);
+}
+
+void job_dependency_delete(Job *subject, Job *object, bool *matters) {
+ JobDependency *l;
+
+ assert(object);
+
+ LIST_FOREACH(object, l, object->object_list) {
+ assert(l->object == object);
+
+ if (l->subject == subject)
+ break;
+ }
+
+ if (!l) {
+ if (matters)
+ *matters = false;
+ return;
+ }
+
+ if (matters)
+ *matters = l->matters;
+
+ job_dependency_free(l);
+}
+
+void job_dump(Job *j, FILE*f, const char *prefix) {
+
+
+ assert(j);
+ assert(f);
+
+ fprintf(f,
+ "%s-> Job %u:\n"
+ "%s\tAction: %s -> %s\n"
+ "%s\tState: %s\n"
+ "%s\tForced: %s\n",
+ prefix, j->id,
+ prefix, j->unit->meta.id, job_type_to_string(j->type),
+ prefix, job_state_to_string(j->state),
+ prefix, yes_no(j->override));
+}
+
+bool job_is_anchor(Job *j) {
+ JobDependency *l;
+
+ assert(j);
+
+ LIST_FOREACH(object, l, j->object_list)
+ if (!l->subject)
+ return true;
+
+ return false;
+}
+
+static bool types_match(JobType a, JobType b, JobType c, JobType d) {
+ return
+ (a == c && b == d) ||
+ (a == d && b == c);
+}
+
+int job_type_merge(JobType *a, JobType b) {
+ if (*a == b)
+ return 0;
+
+ /* Merging is associative! a merged with b merged with c is
+ * the same as a merged with c merged with b. */
+
+ /* Mergeability is transitive! if a can be merged with b and b
+ * with c then a also with c */
+
+ /* Also, if a merged with b cannot be merged with c, then
+ * either a or b cannot be merged with c either */
+
+ if (types_match(*a, b, JOB_START, JOB_VERIFY_ACTIVE))
+ *a = JOB_START;
+ else if (types_match(*a, b, JOB_START, JOB_RELOAD) ||
+ types_match(*a, b, JOB_START, JOB_RELOAD_OR_START) ||
+ types_match(*a, b, JOB_VERIFY_ACTIVE, JOB_RELOAD_OR_START) ||
+ types_match(*a, b, JOB_RELOAD, JOB_RELOAD_OR_START))
+ *a = JOB_RELOAD_OR_START;
+ else if (types_match(*a, b, JOB_START, JOB_RESTART) ||
+ types_match(*a, b, JOB_START, JOB_TRY_RESTART) ||
+ types_match(*a, b, JOB_VERIFY_ACTIVE, JOB_RESTART) ||
+ types_match(*a, b, JOB_RELOAD, JOB_RESTART) ||
+ types_match(*a, b, JOB_RELOAD_OR_START, JOB_RESTART) ||
+ types_match(*a, b, JOB_RELOAD_OR_START, JOB_TRY_RESTART) ||
+ types_match(*a, b, JOB_RESTART, JOB_TRY_RESTART))
+ *a = JOB_RESTART;
+ else if (types_match(*a, b, JOB_VERIFY_ACTIVE, JOB_RELOAD))
+ *a = JOB_RELOAD;
+ else if (types_match(*a, b, JOB_VERIFY_ACTIVE, JOB_TRY_RESTART) ||
+ types_match(*a, b, JOB_RELOAD, JOB_TRY_RESTART))
+ *a = JOB_TRY_RESTART;
+ else
+ return -EEXIST;
+
+ return 0;
+}
+
+bool job_type_is_mergeable(JobType a, JobType b) {
+ return job_type_merge(&a, b) >= 0;
+}
+
+bool job_type_is_superset(JobType a, JobType b) {
+
+ /* Checks whether operation a is a "superset" of b in its
+ * actions */
+
+ if (a == b)
+ return true;
+
+ switch (a) {
+ case JOB_START:
+ return b == JOB_VERIFY_ACTIVE;
+
+ case JOB_RELOAD:
+ return
+ b == JOB_VERIFY_ACTIVE;
+
+ case JOB_RELOAD_OR_START:
+ return
+ b == JOB_RELOAD ||
+ b == JOB_START ||
+ b == JOB_VERIFY_ACTIVE;
+
+ case JOB_RESTART:
+ return
+ b == JOB_START ||
+ b == JOB_VERIFY_ACTIVE ||
+ b == JOB_RELOAD ||
+ b == JOB_RELOAD_OR_START ||
+ b == JOB_TRY_RESTART;
+
+ case JOB_TRY_RESTART:
+ return
+ b == JOB_VERIFY_ACTIVE ||
+ b == JOB_RELOAD;
+ default:
+ return false;
+
+ }
+}
+
+bool job_type_is_conflicting(JobType a, JobType b) {
+ assert(a >= 0 && a < _JOB_TYPE_MAX);
+ assert(b >= 0 && b < _JOB_TYPE_MAX);
+
+ return (a == JOB_STOP) != (b == JOB_STOP);
+}
+
+bool job_type_is_redundant(JobType a, UnitActiveState b) {
+ switch (a) {
+
+ case JOB_START:
+ return
+ b == UNIT_ACTIVE ||
+ b == UNIT_ACTIVE_RELOADING;
+
+ case JOB_STOP:
+ return
+ b == UNIT_INACTIVE;
+
+ case JOB_VERIFY_ACTIVE:
+ return
+ b == UNIT_ACTIVE ||
+ b == UNIT_ACTIVE_RELOADING;
+
+ case JOB_RELOAD:
+ return
+ b == UNIT_ACTIVE_RELOADING;
+
+ case JOB_RELOAD_OR_START:
+ return
+ b == UNIT_ACTIVATING ||
+ b == UNIT_ACTIVE_RELOADING;
+
+ case JOB_RESTART:
+ return
+ b == UNIT_ACTIVATING;
+
+ case JOB_TRY_RESTART:
+ return
+ b == UNIT_ACTIVATING;
+
+ default:
+ assert_not_reached("Invalid job type");
+ }
+}
+
+bool job_is_runnable(Job *j) {
+ Iterator i;
+ Unit *other;
+
+ assert(j);
+ assert(j->installed);
+
+ /* Checks whether there is any job running for the units this
+ * job needs to be running after (in the case of a 'positive'
+ * job type) or before (in the case of a 'negative' job type
+ * . */
+
+ if (j->type == JOB_START ||
+ j->type == JOB_VERIFY_ACTIVE ||
+ j->type == JOB_RELOAD ||
+ j->type == JOB_RELOAD_OR_START) {
+
+ /* Immediate result is that the job is or might be
+ * started. In this case lets wait for the
+ * dependencies, regardless whether they are
+ * starting or stopping something. */
+
+ SET_FOREACH(other, j->unit->meta.dependencies[UNIT_AFTER], i)
+ if (other->meta.job)
+ return false;
+ }
+
+ /* Also, if something else is being stopped and we should
+ * change state after it, then lets wait. */
+
+ SET_FOREACH(other, j->unit->meta.dependencies[UNIT_BEFORE], i)
+ if (other->meta.job &&
+ (other->meta.job->type == JOB_STOP ||
+ other->meta.job->type == JOB_RESTART ||
+ other->meta.job->type == JOB_TRY_RESTART))
+ return false;
+
+ /* This means that for a service a and a service b where b
+ * shall be started after a:
+ *
+ * start a + start b → 1st step start a, 2nd step start b
+ * start a + stop b → 1st step stop b, 2nd step start a
+ * stop a + start b → 1st step stop a, 2nd step start b
+ * stop a + stop b → 1st step stop b, 2nd step stop a
+ *
+ * This has the side effect that restarts are properly
+ * synchronized too. */
+
+ return true;
+}
+
+int job_run_and_invalidate(Job *j) {
+ int r;
+
+ assert(j);
+ assert(j->installed);
+
+ if (j->in_run_queue) {
+ LIST_REMOVE(Job, run_queue, j->manager->run_queue, j);
+ j->in_run_queue = false;
+ }
+
+ if (j->state != JOB_WAITING)
+ return 0;
+
+ if (!job_is_runnable(j))
+ return -EAGAIN;
+
+ j->state = JOB_RUNNING;
+ job_add_to_dbus_queue(j);
+
+ switch (j->type) {
+
+ case JOB_START:
+ r = unit_start(j->unit);
+ if (r == -EBADR)
+ r = 0;
+ break;
+
+ case JOB_VERIFY_ACTIVE: {
+ UnitActiveState t = unit_active_state(j->unit);
+ if (UNIT_IS_ACTIVE_OR_RELOADING(t))
+ r = -EALREADY;
+ else if (t == UNIT_ACTIVATING)
+ r = -EAGAIN;
+ else
+ r = -ENOEXEC;
+ break;
+ }
+
+ case JOB_STOP:
+ r = unit_stop(j->unit);
+ break;
+
+ case JOB_RELOAD:
+ r = unit_reload(j->unit);
+ break;
+
+ case JOB_RELOAD_OR_START:
+ if (unit_active_state(j->unit) == UNIT_ACTIVE)
+ r = unit_reload(j->unit);
+ else
+ r = unit_start(j->unit);
+ break;
+
+ case JOB_RESTART: {
+ UnitActiveState t = unit_active_state(j->unit);
+ if (t == UNIT_INACTIVE || t == UNIT_ACTIVATING) {
+ j->type = JOB_START;
+ r = unit_start(j->unit);
+ } else
+ r = unit_stop(j->unit);
+ break;
+ }
+
+ case JOB_TRY_RESTART: {
+ UnitActiveState t = unit_active_state(j->unit);
+ if (t == UNIT_INACTIVE || t == UNIT_DEACTIVATING)
+ r = -ENOEXEC;
+ else if (t == UNIT_ACTIVATING) {
+ j->type = JOB_START;
+ r = unit_start(j->unit);
+ } else
+ r = unit_stop(j->unit);
+ break;
+ }
+
+ default:
+ assert_not_reached("Unknown job type");
+ }
+
+ if (r == -EALREADY)
+ r = job_finish_and_invalidate(j, true);
+ else if (r == -EAGAIN) {
+ j->state = JOB_WAITING;
+ return -EAGAIN;
+ } else if (r < 0)
+ r = job_finish_and_invalidate(j, false);
+
+ return r;
+}
+
+int job_finish_and_invalidate(Job *j, bool success) {
+ Unit *u;
+ Unit *other;
+ JobType t;
+ Iterator i;
+
+ assert(j);
+ assert(j->installed);
+
+ log_debug("Job %s/%s finished, success=%s", j->unit->meta.id, job_type_to_string(j->type), yes_no(success));
+ job_add_to_dbus_queue(j);
+
+ /* Patch restart jobs so that they become normal start jobs */
+ if (success && (j->type == JOB_RESTART || j->type == JOB_TRY_RESTART)) {
+
+ log_debug("Converting job %s/%s -> %s/%s",
+ j->unit->meta.id, job_type_to_string(j->type),
+ j->unit->meta.id, job_type_to_string(JOB_START));
+
+ j->state = JOB_RUNNING;
+ j->type = JOB_START;
+
+ job_add_to_run_queue(j);
+ return 0;
+ }
+
+ u = j->unit;
+ t = j->type;
+ job_free(j);
+
+ /* Fail depending jobs on failure */
+ if (!success) {
+
+ if (t == JOB_START ||
+ t == JOB_VERIFY_ACTIVE ||
+ t == JOB_RELOAD_OR_START) {
+
+ SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
+ if (other->meta.job &&
+ (other->meta.job->type == JOB_START ||
+ other->meta.job->type == JOB_VERIFY_ACTIVE ||
+ other->meta.job->type == JOB_RELOAD_OR_START))
+ job_finish_and_invalidate(other->meta.job, false);
+
+ SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
+ if (other->meta.job &&
+ !other->meta.job->override &&
+ (other->meta.job->type == JOB_START ||
+ other->meta.job->type == JOB_VERIFY_ACTIVE ||
+ other->meta.job->type == JOB_RELOAD_OR_START))
+ job_finish_and_invalidate(other->meta.job, false);
+
+ } else if (t == JOB_STOP) {
+
+ SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
+ if (other->meta.job &&
+ (other->meta.job->type == JOB_START ||
+ other->meta.job->type == JOB_VERIFY_ACTIVE ||
+ other->meta.job->type == JOB_RELOAD_OR_START))
+ job_finish_and_invalidate(other->meta.job, false);
+ }
+ }
+
+ /* Try to start the next jobs that can be started */
+ SET_FOREACH(other, u->meta.dependencies[UNIT_AFTER], i)
+ if (other->meta.job)
+ job_add_to_run_queue(other->meta.job);
+ SET_FOREACH(other, u->meta.dependencies[UNIT_BEFORE], i)
+ if (other->meta.job)
+ job_add_to_run_queue(other->meta.job);
+
+ return 0;
+}
+
+void job_add_to_run_queue(Job *j) {
+ assert(j);
+ assert(j->installed);
+
+ if (j->in_run_queue)
+ return;
+
+ LIST_PREPEND(Job, run_queue, j->manager->run_queue, j);
+ j->in_run_queue = true;
+}
+
+void job_add_to_dbus_queue(Job *j) {
+ assert(j);
+ assert(j->installed);
+
+ if (j->in_dbus_queue)
+ return;
+
+ if (set_isempty(j->manager->subscribed)) {
+ j->sent_dbus_new_signal = true;
+ return;
+ }
+
+ LIST_PREPEND(Job, dbus_queue, j->manager->dbus_job_queue, j);
+ j->in_dbus_queue = true;
+}
+
+char *job_dbus_path(Job *j) {
+ char *p;
+
+ assert(j);
+
+ if (asprintf(&p, "/org/freedesktop/systemd1/job/%lu", (unsigned long) j->id) < 0)
+ return NULL;
+
+ return p;
+}
+
+static const char* const job_state_table[_JOB_STATE_MAX] = {
+ [JOB_WAITING] = "waiting",
+ [JOB_RUNNING] = "running"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(job_state, JobState);
+
+static const char* const job_type_table[_JOB_TYPE_MAX] = {
+ [JOB_START] = "start",
+ [JOB_VERIFY_ACTIVE] = "verify-active",
+ [JOB_STOP] = "stop",
+ [JOB_RELOAD] = "reload",
+ [JOB_RELOAD_OR_START] = "reload-or-start",
+ [JOB_RESTART] = "restart",
+ [JOB_TRY_RESTART] = "try-restart",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(job_type, JobType);
+
+static const char* const job_mode_table[_JOB_MODE_MAX] = {
+ [JOB_FAIL] = "fail",
+ [JOB_REPLACE] = "replace",
+ [JOB_ISOLATE] = "isolate"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(job_mode, JobMode);
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-24 01:16:03 +0000