1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
13 Manager* manager_new(void) {
16 if (!(m = new0(Manager, 1)))
19 if (!(m->names = hashmap_new(string_hash_func, string_compare_func)))
22 if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
25 if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
35 void manager_free(Manager *m) {
41 while ((n = hashmap_first(m->names)))
44 while ((j = hashmap_steal_first(m->transaction_jobs)))
47 hashmap_free(m->names);
48 hashmap_free(m->jobs);
49 hashmap_free(m->transaction_jobs);
54 static void transaction_abort(Manager *m) {
59 while ((j = hashmap_first(m->transaction_jobs)))
61 manager_transaction_delete_job(m, j);
65 assert(hashmap_isempty(m->transaction_jobs));
66 assert(!m->transaction_anchor);
69 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
74 for (l = j ? j->subject_list : m->transaction_anchor; l; l = l->subject_next) {
76 /* This link does not matter */
80 /* This name has already been marked */
81 if (l->object->generation == generation)
84 l->object->matters_to_anchor = true;
85 l->object->generation = generation;
87 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
91 static bool types_match(JobType a, JobType b, JobType c, JobType d) {
97 static int types_merge(JobType *a, JobType b) {
101 if (types_match(*a, b, JOB_START, JOB_VERIFY_STARTED))
103 else if (types_match(*a, b, JOB_START, JOB_RELOAD) ||
104 types_match(*a, b, JOB_START, JOB_RELOAD_OR_START) ||
105 types_match(*a, b, JOB_VERIFY_STARTED, JOB_RELOAD_OR_START) ||
106 types_match(*a, b, JOB_RELOAD, JOB_RELOAD_OR_START))
107 *a = JOB_RELOAD_OR_START;
108 else if (types_match(*a, b, JOB_START, JOB_RESTART) ||
109 types_match(*a, b, JOB_START, JOB_TRY_RESTART) ||
110 types_match(*a, b, JOB_VERIFY_STARTED, JOB_RESTART) ||
111 types_match(*a, b, JOB_RELOAD, JOB_RESTART) ||
112 types_match(*a, b, JOB_RELOAD_OR_START, JOB_RESTART) ||
113 types_match(*a, b, JOB_RELOAD_OR_START, JOB_TRY_RESTART) ||
114 types_match(*a, b, JOB_RESTART, JOB_TRY_RESTART))
116 else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_RELOAD))
118 else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_TRY_RESTART) ||
119 types_match(*a, b, JOB_RELOAD, JOB_TRY_RESTART))
120 *a = JOB_TRY_RESTART;
125 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
126 JobDependency *l, *last;
130 assert(j->name == other->name);
134 j->state = JOB_WAITING;
136 j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
138 /* Patch us in as new owner of the JobDependency objects */
140 for (l = other->subject_list; l; l = l->subject_next) {
141 assert(l->subject == other);
146 /* Merge both lists */
148 last->subject_next = j->subject_list;
150 j->subject_list->subject_prev = last;
151 j->subject_list = other->subject_list;
154 /* Patch us in as new owner of the JobDependency objects */
156 for (l = other->object_list; l; l = l->object_next) {
157 assert(l->object == other);
162 /* Merge both lists */
164 last->object_next = j->object_list;
166 j->object_list->object_prev = last;
167 j->object_list = other->object_list;
170 /* Kill the other job */
171 other->subject_list = NULL;
172 other->object_list = NULL;
173 manager_transaction_delete_job(m, other);
176 static int transaction_merge_jobs(Manager *m) {
183 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
187 for (k = j->transaction_next; k; k = k->transaction_next)
188 if ((r = types_merge(&t, k->type)) < 0)
191 while ((k = j->transaction_next)) {
193 transaction_merge_and_delete_job(m, k, j, t);
196 transaction_merge_and_delete_job(m, j, k, t);
199 assert(!j->transaction_next);
200 assert(!j->transaction_prev);
206 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation) {
214 /* Did we find a cycle? */
215 if (j->marker && j->generation == generation) {
218 /* So, we already have been here. We have a
219 * cycle. Let's try to break it. We go backwards in our
220 * path and try to find a suitable job to remove. */
222 for (k = from; k; k = (k->generation == generation ? k->marker : NULL)) {
223 if (!k->matters_to_anchor) {
224 log_debug("Breaking order cycle by deleting job %s", name_id(k->name));
225 manager_transaction_delete_job(m, k);
229 /* Check if this in fact was the beginning of
239 j->generation = generation;
241 /* We assume that the the dependencies are both-ways, and
242 * hence can ignore NAME_AFTER */
244 SET_FOREACH(n, j->name->meta.dependencies[NAME_BEFORE], state) {
247 if (!(o = hashmap_get(m->transaction_jobs, n)))
248 if (!(o = n->meta.job))
251 if ((r = transaction_verify_order_one(m, o, j, generation)) < 0)
258 static int transaction_verify_order(Manager *m, unsigned *generation) {
270 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
273 assert(!j->transaction_next);
274 assert(!j->transaction_prev);
276 if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0) {
278 /* There was a cycleq, but it was fixed,
279 * we need to restart our algorithm */
293 static void transaction_collect_garbage(Manager *m) {
304 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
308 manager_transaction_delete_job(m, j);
316 static int transaction_is_destructive(Manager *m, JobMode mode) {
322 /* Checks whether applying this transaction means that
323 * existing jobs would be replaced */
325 HASHMAP_FOREACH(j, m->transaction_jobs, state)
326 if (j->name->meta.job && j->name->meta.job != j)
332 static int transaction_apply(Manager *m, JobMode mode) {
337 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
341 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
345 while ((j = hashmap_steal_first(m->transaction_jobs))) {
349 if (j->name->meta.job)
350 job_free(j->name->meta.job);
352 j->name->meta.job = j;
355 /* We're fully installed. Now let's free data we don't
358 assert(!j->transaction_next);
359 assert(!j->transaction_prev);
361 while (j->subject_list)
362 job_dependency_free(j->subject_list);
363 while (j->object_list)
364 job_dependency_free(j->object_list);
371 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
375 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
382 static int transaction_activate(Manager *m, JobMode mode) {
384 unsigned generation = 1;
388 /* This applies the changes recorded in transaction_jobs to
389 * the actual list of jobs, if possible. */
391 /* First step: figure out which jobs matter */
392 transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
394 /* Second step: let's merge entries we can merge */
395 if ((r = transaction_merge_jobs(m)) < 0)
398 /* Third step: verify order makes sense */
399 if ((r = transaction_verify_order(m, &generation)) < 0)
402 /* Third step: do garbage colletion */
403 transaction_collect_garbage(m);
405 /* Fourth step: check whether we can actually apply this */
406 if (mode == JOB_FAIL)
407 if ((r = transaction_is_destructive(m, mode)) < 0)
410 /* Fifth step: apply changes */
411 if ((r = transaction_apply(m, mode)) < 0)
414 assert(hashmap_isempty(m->transaction_jobs));
415 assert(!m->transaction_anchor);
420 transaction_abort(m);
424 static Job* transaction_add_one_job(Manager *m, JobType type, Name *name, bool *is_new) {
431 /* Looks for an axisting prospective job and returns that. If
432 * it doesn't exist it is created and added to the prospective
435 f = hashmap_get(m->transaction_jobs, name);
437 for (j = f; j; j = j->transaction_next) {
438 assert(j->name == name);
440 if (j->type == type) {
447 if (name->meta.job && name->meta.job->type == type)
449 else if (!(j = job_new(m, type, name)))
452 if ((r = hashmap_replace(m->transaction_jobs, name, j)) < 0) {
457 j->transaction_next = f;
460 f->transaction_prev = j;
464 j->matters_to_anchor = false;
472 void manager_transaction_delete_job(Manager *m, Job *j) {
476 if (j->transaction_prev)
477 j->transaction_prev->transaction_next = j->transaction_next;
478 else if (j->transaction_next)
479 hashmap_replace(m->transaction_jobs, j->name, j->transaction_next);
481 hashmap_remove_value(m->transaction_jobs, j->name, j);
483 if (j->transaction_next)
484 j->transaction_next->transaction_prev = j->transaction_prev;
486 j->transaction_prev = j->transaction_next = NULL;
488 while (j->subject_list)
489 job_dependency_free(j->subject_list);
491 while (j->object_list) {
492 Job *other = j->object_list->matters ? j->object_list->subject : NULL;
494 job_dependency_free(j->object_list);
497 log_debug("Deleting job %s, as dependency of job %s", name_id(j->name), name_id(other->name));
498 manager_transaction_delete_job(m, other);
503 static int transaction_add_job_and_dependencies(Manager *m, JobType type, Name *name, Job *by, bool matters, bool force, Job **_ret) {
511 assert(type < _JOB_TYPE_MAX);
514 if (name->meta.state != NAME_LOADED)
517 /* First add the job. */
518 if (!(ret = transaction_add_one_job(m, type, name, &is_new)))
521 /* Then, add a link to the job. */
522 if (!job_dependency_new(by, ret, matters))
526 /* Finally, recursively add in all dependencies. */
527 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
528 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRES], state)
529 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, force, NULL)) < 0)
531 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUIRES], state)
532 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !force, force, NULL)) < 0)
534 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_WANTS], state)
535 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, force, NULL)) < 0)
537 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUISITE], state)
538 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, true, force, NULL)) < 0)
540 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUISITE], state)
541 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, !force, force, NULL)) < 0)
543 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_CONFLICTS], state)
544 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, force, NULL)) < 0)
547 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
549 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRED_BY], state)
550 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, force, NULL)) < 0)
554 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
563 int manager_add_job(Manager *m, JobType type, Name *name, JobMode mode, bool force, Job **_ret) {
568 assert(type < _JOB_TYPE_MAX);
570 assert(mode < _JOB_MODE_MAX);
572 if ((r = transaction_add_job_and_dependencies(m, type, name, NULL, true, force, &ret))) {
573 transaction_abort(m);
577 if ((r = transaction_activate(m, mode)) < 0)
586 Job *manager_get_job(Manager *m, uint32_t id) {
589 return hashmap_get(m->jobs, UINT32_TO_PTR(id));
592 Name *manager_get_name(Manager *m, const char *name) {
596 return hashmap_get(m->names, name);
599 static int dispatch_load_queue(Manager *m) {
604 /* Make sure we are not run recursively */
605 if (m->dispatching_load_queue)
608 m->dispatching_load_queue = true;
610 /* Dispatches the load queue. Takes a name from the queue and
611 * tries to load its data until the queue is empty */
613 while ((meta = m->load_queue)) {
614 name_load(NAME(meta));
615 LIST_REMOVE(Meta, m->load_queue, meta);
618 m->dispatching_load_queue = false;
623 int manager_load_name(Manager *m, const char *name, Name **_ret) {
633 if (!name_is_valid(name))
636 /* This will load the service information files, but not actually
637 * start any services or anything */
639 if ((ret = manager_get_name(m, name)))
642 if ((t = name_type_from_string(name)) == _NAME_TYPE_INVALID)
645 if (!(ret = name_new(m)))
650 if (!(n = strdup(name))) {
655 if (set_put(ret->meta.names, n) < 0) {
661 if ((r = name_link(ret)) < 0) {
666 /* At this point the new entry is created and linked. However,
667 * not loaded. Now load this entry and all its dependencies
670 dispatch_load_queue(m);
678 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
685 HASHMAP_FOREACH(j, s->jobs, state)
686 job_dump(j, f, prefix);
689 void manager_dump_names(Manager *s, FILE *f, const char *prefix) {
697 HASHMAP_FOREACH_KEY(n, t, s->names, state)
699 name_dump(n, f, prefix);
702 void manager_clear_jobs(Manager *m) {
707 transaction_abort(m);
709 while ((j = hashmap_first(m->jobs)))