first attempt in implementinging execution logic

1 files changed, 227 insertions, 30 deletions

diff --git a/job.c b/job.c
index 4688164e5a..0ae1a765fb 100644
--- a/job.c
+++ b/job.c
@@ -30,14 +30,15 @@ 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;
 
                 hashmap_remove(j->manager->jobs, UINT32_TO_PTR(j->id));
+                j->linked = false;
         }
 
+        /* Detach from next 'smaller' objects */
         manager_transaction_unlink_job(j->manager, j);
 
         free(j);
@@ -132,15 +133,14 @@ const char* job_type_to_string(JobType t) {
 
         static const char* const job_type_table[_JOB_TYPE_MAX] = {
                 [JOB_START] = "start",
+                [JOB_VERIFY_ACTIVE] = "verify-active",
                 [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";
 
@@ -151,8 +151,7 @@ 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"
+                [JOB_RUNNING] = "running"
         };
 
         assert(j);
@@ -161,10 +160,12 @@ void job_dump(Job *j, FILE*f, const char *prefix) {
         fprintf(f,
                 "%sJob %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, job_state_table[j->state],
+                prefix, yes_no(j->forced));
 }
 
 bool job_is_anchor(Job *j) {
@@ -198,24 +199,24 @@ 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
@@ -224,40 +225,43 @@ 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;
@@ -269,30 +273,223 @@ 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) ||
-                (b == JOB_STOP && a != JOB_STOP);
+        return (a == JOB_STOP) != (b == JOB_STOP);
 }
 
-bool job_type_applicable(JobType j, NameType n) {
+bool job_type_is_applicable(JobType j, NameType n) {
         assert(j >= 0 && j < _JOB_TYPE_MAX);
         assert(n >= 0 && n < _NAME_TYPE_MAX);
 
         switch (j) {
+                case JOB_VERIFY_ACTIVE:
                 case JOB_START:
-                case JOB_STOP:
-                case JOB_VERIFY_STARTED:
                         return true;
 
-                case JOB_RELOAD:
-                case JOB_RELOAD_OR_START:
-                        return n == NAME_SERVICE || n == NAME_TIMER || n == NAME_MOUNT;
-
+                case JOB_STOP:
                 case JOB_RESTART:
                 case JOB_TRY_RESTART:
-                        return n == NAME_SERVICE || n == NAME_TIMER || n == NAME_SOCKET || NAME_MOUNT || NAME_SNAPSHOT;
+                        return name_type_can_start(n);
+
+                case JOB_RELOAD:
+                        return name_type_can_reload(n);
+
+                case JOB_RELOAD_OR_START:
+                        return name_type_can_reload(n) && name_type_can_start(n);
 
                 default:
                         assert_not_reached("Invalid job type");
         }
 }
+
+bool job_is_runnable(Job *j) {
+        void *state;
+        Name *other;
+
+        assert(j);
+        assert(j->linked);
+
+        /* Checks whether there is any job running for the names 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->name->meta.dependencies[NAME_AFTER], state)
+                        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->name->meta.dependencies[NAME_BEFORE], state)
+                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);
+
+        if (!job_is_runnable(j))
+                return -EAGAIN;
+
+        if (j->state != JOB_WAITING)
+                return 0;
+
+        switch (j->type) {
+
+                case JOB_START:
+                        r = name_start(j->name);
+                        if (r == -EBADR)
+                                r = 0;
+                        break;
+
+                case JOB_VERIFY_ACTIVE: {
+                        NameActiveState t = name_active_state(j->name);
+                        if (NAME_IS_ACTIVE_OR_RELOADING(t))
+                                r = -EALREADY;
+                        else if (t == NAME_ACTIVATING)
+                                r = -EAGAIN;
+                        else
+                                r = -ENOEXEC;
+                        break;
+                }
+
+                case JOB_STOP:
+                        r = name_stop(j->name);
+                        break;
+
+                case JOB_RELOAD:
+                        r = name_reload(j->name);
+                        break;
+
+                case JOB_RELOAD_OR_START:
+                        if (name_active_state(j->name) == NAME_ACTIVE)
+                                r = name_reload(j->name);
+                        else
+                                r = name_start(j->name);
+                        break;
+
+                case JOB_RESTART: {
+                        NameActiveState t = name_active_state(j->name);
+                        if (t == NAME_INACTIVE || t == NAME_ACTIVATING) {
+                                j->type = JOB_START;
+                                r = name_start(j->name);
+                        } else
+                                r = name_stop(j->name);
+                        break;
+                }
+
+                case JOB_TRY_RESTART: {
+                        NameActiveState t = name_active_state(j->name);
+                        if (t == NAME_INACTIVE || t == NAME_DEACTIVATING)
+                                r = -ENOEXEC;
+                        else if (t == NAME_ACTIVATING) {
+                                j->type = JOB_START;
+                                r = name_start(j->name);
+                        } else
+                                r = name_stop(j->name);
+                        break;
+                }
+
+                default:
+                        ;
+        }
+
+        if (r >= 0)
+                j->state = JOB_RUNNING;
+        else if (r == -EALREADY)
+                r = job_finish_and_invalidate(j, true);
+        else if (r != -EAGAIN)
+                r = job_finish_and_invalidate(j, false);
+
+        return r;
+}
+
+int job_finish_and_invalidate(Job *j, bool success) {
+        Name *n;
+        void *state;
+        Name *other;
+        NameType t;
+
+        assert(j);
+
+        if (success && (j->type == JOB_RESTART || j->type == JOB_TRY_RESTART)) {
+                j->state = JOB_RUNNING;
+                j->type = JOB_START;
+                return job_run_and_invalidate(j);
+        }
+
+        n = j->name;
+        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, n->meta.dependencies[NAME_REQUIRED_BY], state)
+                                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, n->meta.dependencies[NAME_SOFT_REQUIRED_BY], state)
+                                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, n->meta.dependencies[NAME_CONFLICTS], state)
+                                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, n->meta.dependencies[NAME_AFTER], state)
+                if (other->meta.job)
+                        job_run_and_invalidate(other->meta.job);
+        SET_FOREACH(other, n->meta.dependencies[NAME_BEFORE], state)
+                if (other->meta.job)
+                        job_run_and_invalidate(other->meta.job);
+
+        return 0;
+}