chiark / gitweb /
add basic (and not very useful) D-Bus support
[elogind.git] / job.c
diff --git a/job.c b/job.c
index 6241f20..d02551a 100644 (file)
--- a/job.c
+++ b/job.c
@@ -3,15 +3,20 @@
 #include <assert.h>
 #include <errno.h>
 
+#include "set.h"
+#include "unit.h"
 #include "macro.h"
-#include "job.h"
+#include "strv.h"
+#include "load-fragment.h"
+#include "load-dropin.h"
+#include "log.h"
 
-Job* job_new(Manager *m, JobType type, Name *name) {
+Job* job_new(Manager *m, JobType type, Unit *unit) {
         Job *j;
 
         assert(m);
         assert(type < _JOB_TYPE_MAX);
-        assert(name);
+        assert(unit);
 
         if (!(j = new0(Job, 1)))
                 return NULL;
@@ -19,7 +24,7 @@ Job* job_new(Manager *m, JobType type, Name *name) {
         j->manager = m;
         j->id = m->current_job_id++;
         j->type = type;
-        j->name = name;
+        j->unit = unit;
 
         /* We don't link it here, that's what job_dependency() is for */
 
@@ -30,14 +35,15 @@ void job_free(Job *j) {
         assert(j);
 
         /* Detach from next 'bigger' objects */
-
-        if (j->linked) {
-                if (j->name->meta.job == j)
-                        j->name->meta.job = NULL;
+        if (j->installed) {
+                if (j->unit->meta.job == j)
+                        j->unit->meta.job = NULL;
 
                 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);
 
         free(j);
@@ -60,22 +66,12 @@ JobDependency* job_dependency_new(Job *subject, Job *object, bool matters) {
         l->object = object;
         l->matters = matters;
 
-        if (subject) {
-                l->subject_next = subject->subject_list;
-                subject->subject_list = l;
-        } else {
-                l->subject_next = object->manager->transaction_anchor;
-                object->manager->transaction_anchor = l;
-        }
-
-        if (l->subject_next)
-                l->subject_next->subject_prev = l;
-        l->subject_prev = NULL;
+        if (subject)
+                LIST_PREPEND(JobDependency, subject, subject->subject_list, l);
+        else
+                LIST_PREPEND(JobDependency, subject, object->manager->transaction_anchor, l);
 
-        if ((l->object_next = object->object_list))
-                l->object_next->object_prev = l;
-        l->object_prev = NULL;
-        object->object_list = l;
+        LIST_PREPEND(JobDependency, object, object->object_list, l);
 
         return l;
 }
@@ -83,23 +79,12 @@ JobDependency* job_dependency_new(Job *subject, Job *object, bool matters) {
 void job_dependency_free(JobDependency *l) {
         assert(l);
 
-        if (l->subject_prev)
-                l->subject_prev->subject_next = l->subject_next;
-        else if (l->subject)
-                l->subject->subject_list = l->subject_next;
-        else
-                l->object->manager->transaction_anchor = l->subject_next;
-
-        if (l->subject_next)
-                l->subject_next->subject_prev = l->subject_prev;
-
-        if (l->object_prev)
-                l->object_prev->object_next = l->object_next;
+        if (l->subject)
+                LIST_REMOVE(JobDependency, subject, l->subject->subject_list, l);
         else
-                l->object->object_list = l->object_next;
+                LIST_REMOVE(JobDependency, subject, l->object->manager->transaction_anchor, l);
 
-        if (l->object_next)
-                l->object_next->object_prev = l->object_prev;
+        LIST_REMOVE(JobDependency, object, l->object->object_list, l);
 
         free(l);
 }
@@ -109,7 +94,7 @@ void job_dependency_delete(Job *subject, Job *object, bool *matters) {
 
         assert(object);
 
-        for (l = object->object_list; l; l = l->object_next) {
+        LIST_FOREACH(object, l, object->object_list) {
                 assert(l->object == object);
 
                 if (l->subject == subject)
@@ -128,43 +113,21 @@ void job_dependency_delete(Job *subject, Job *object, bool *matters) {
         job_dependency_free(l);
 }
 
-const char* job_type_to_string(JobType t) {
-
-        static const char* const job_type_table[_JOB_TYPE_MAX] = {
-                [JOB_START] = "start",
-                [JOB_STOP] = "stop",
-                [JOB_VERIFY_STARTED] = "verify-started",
-                [JOB_RELOAD] = "reload",
-                [JOB_RELOAD_OR_START] = "reload-or-start",
-                [JOB_RESTART] = "restart",
-                [JOB_TRY_RESTART] = "try-restart",
-        };
-
-
-        if (t < 0 || t >= _JOB_TYPE_MAX)
-                return "n/a";
-
-        return job_type_table[t];
-}
-
 void job_dump(Job *j, FILE*f, const char *prefix) {
 
-        static const char* const job_state_table[_JOB_STATE_MAX] = {
-                [JOB_WAITING] = "waiting",
-                [JOB_RUNNING] = "running",
-                [JOB_DONE] = "done"
-        };
 
         assert(j);
         assert(f);
 
         fprintf(f,
-                "%sJob %u:\n"
+                "%s→ Job %u:\n"
                 "%s\tAction: %s → %s\n"
-                "%s\tState: %s\n",
+                "%s\tState: %s\n"
+                "%s\tForced: %s\n",
                 prefix, j->id,
-                prefix, name_id(j->name), job_type_to_string(j->type),
-                prefix, job_state_table[j->state]);
+                prefix, unit_id(j->unit), job_type_to_string(j->type),
+                prefix, job_state_to_string(j->state),
+                prefix, yes_no(j->forced));
 }
 
 bool job_is_anchor(Job *j) {
@@ -172,7 +135,7 @@ bool job_is_anchor(Job *j) {
 
         assert(j);
 
-        for (l = j->object_list; l; l = l->object_next)
+        LIST_FOREACH(object, l, j->object_list)
                 if (!l->subject)
                         return true;
 
@@ -198,24 +161,24 @@ int job_type_merge(JobType *a, JobType b) {
         /* 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_STARTED))
+        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_STARTED, 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_STARTED, JOB_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_STARTED, JOB_RELOAD))
+        else if (types_match(*a, b, JOB_VERIFY_ACTIVE, JOB_RELOAD))
                 *a = JOB_RELOAD;
-        else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_TRY_RESTART) ||
+        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
@@ -224,43 +187,308 @@ int job_type_merge(JobType *a, JobType b) {
         return 0;
 }
 
-bool job_type_mergeable(JobType a, JobType b) {
+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 */
+        /* 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_STARTED;
+                        return b == JOB_VERIFY_ACTIVE;
 
                 case JOB_RELOAD:
-                        return b == JOB_VERIFY_STARTED;
+                        return
+                                b == JOB_VERIFY_ACTIVE;
 
                 case JOB_RELOAD_OR_START:
                         return
                                 b == JOB_RELOAD ||
-                                b == JOB_START;
+                                b == JOB_START ||
+                                b == JOB_VERIFY_ACTIVE;
 
                 case JOB_RESTART:
                         return
                                 b == JOB_START ||
-                                b == JOB_VERIFY_STARTED ||
+                                b == JOB_VERIFY_ACTIVE ||
                                 b == JOB_RELOAD ||
                                 b == JOB_RELOAD_OR_START ||
                                 b == JOB_TRY_RESTART;
 
                 case JOB_TRY_RESTART:
                         return
-                                b == JOB_VERIFY_STARTED ||
+                                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_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;
+
+        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;
+        UnitType t;
+        Iterator i;
+
+        assert(j);
+        assert(j->installed);
+
+        log_debug("Job %s/%s finished, success=%s", unit_id(j->unit), job_type_to_string(j->type), yes_no(success));
+
+        /* 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",
+                          unit_id(j->unit), job_type_to_string(j->type),
+                          unit_id(j->unit), job_type_to_string(JOB_START));
+
+                j->state = JOB_RUNNING;
+                j->type = JOB_START;
+
+                job_schedule_run(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.type == JOB_START ||
+                                     other->meta.type == JOB_VERIFY_ACTIVE ||
+                                     other->meta.type == JOB_RELOAD_OR_START))
+                                        job_finish_and_invalidate(other->meta.job, false);
+
+                        SET_FOREACH(other, u->meta.dependencies[UNIT_SOFT_REQUIRED_BY], i)
+                                if (other->meta.job &&
+                                    !other->meta.job->forced &&
+                                    (other->meta.type == JOB_START ||
+                                     other->meta.type == JOB_VERIFY_ACTIVE ||
+                                     other->meta.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 &&
+                                    (t == JOB_START ||
+                                     t == JOB_VERIFY_ACTIVE ||
+                                     t == 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_schedule_run(other->meta.job);
+        SET_FOREACH(other, u->meta.dependencies[UNIT_BEFORE], i)
+                if (other->meta.job)
+                        job_schedule_run(other->meta.job);
+
+        return 0;
+}
+
+void job_schedule_run(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;
+}
+
+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);