1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
12 Manager* manager_new(void) {
15 if (!(m = new0(Manager, 1)))
18 if (!(m->names = hashmap_new(string_hash_func, string_compare_func)))
21 if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
24 if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
34 void manager_free(Manager *m) {
40 while ((n = hashmap_first(m->names)))
43 while ((j = hashmap_steal_first(m->transaction_jobs)))
46 hashmap_free(m->names);
47 hashmap_free(m->jobs);
48 hashmap_free(m->transaction_jobs);
53 static void transaction_abort(Manager *m) {
58 while ((j = hashmap_first(m->transaction_jobs)))
60 manager_transaction_delete_job(m, j);
64 assert(hashmap_isempty(m->transaction_jobs));
65 assert(!m->transaction_anchor);
68 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
73 for (l = j ? j->subject_list : m->transaction_anchor; l; l = l->subject_next) {
75 /* This link does not matter */
79 /* This name has already been marked */
80 if (l->object->generation == generation)
83 l->object->matters_to_anchor = true;
84 l->object->generation = generation;
86 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
90 static bool types_match(JobType a, JobType b, JobType c, JobType d) {
96 static int types_merge(JobType *a, JobType b) {
100 if (types_match(*a, b, JOB_START, JOB_VERIFY_STARTED))
102 else if (types_match(*a, b, JOB_START, JOB_RELOAD) ||
103 types_match(*a, b, JOB_START, JOB_RELOAD_OR_START) ||
104 types_match(*a, b, JOB_VERIFY_STARTED, JOB_RELOAD_OR_START) ||
105 types_match(*a, b, JOB_RELOAD, JOB_RELOAD_OR_START))
106 *a = JOB_RELOAD_OR_START;
107 else if (types_match(*a, b, JOB_START, JOB_RESTART) ||
108 types_match(*a, b, JOB_START, JOB_TRY_RESTART) ||
109 types_match(*a, b, JOB_VERIFY_STARTED, JOB_RESTART) ||
110 types_match(*a, b, JOB_RELOAD, JOB_RESTART) ||
111 types_match(*a, b, JOB_RELOAD_OR_START, JOB_RESTART) ||
112 types_match(*a, b, JOB_RELOAD_OR_START, JOB_TRY_RESTART) ||
113 types_match(*a, b, JOB_RESTART, JOB_TRY_RESTART))
115 else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_RELOAD))
117 else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_TRY_RESTART) ||
118 types_match(*a, b, JOB_RELOAD, JOB_TRY_RESTART))
119 *a = JOB_TRY_RESTART;
124 static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) {
125 JobDependency *l, *last;
129 assert(j->name == other->name);
133 j->state = JOB_WAITING;
135 j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
137 /* Patch us in as new owner of the JobDependency objects */
139 for (l = other->subject_list; l; l = l->subject_next) {
140 assert(l->subject == other);
145 /* Merge both lists */
147 last->subject_next = j->subject_list;
149 j->subject_list->subject_prev = last;
150 j->subject_list = other->subject_list;
153 /* Patch us in as new owner of the JobDependency objects */
155 for (l = other->object_list; l; l = l->object_next) {
156 assert(l->object == other);
161 /* Merge both lists */
163 last->object_next = j->object_list;
165 j->object_list->object_prev = last;
166 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 manager_transaction_delete_job(m, k);
228 /* Check if this in fact was the beginning of
238 j->generation = generation;
240 /* We assume that the the dependencies are both-ways, and
241 * hence can ignore NAME_AFTER */
243 SET_FOREACH(n, j->name->meta.dependencies[NAME_BEFORE], state) {
246 if (!(o = hashmap_get(m->transaction_jobs, n)))
247 if (!(o = n->meta.job))
250 if ((r = transaction_verify_order_one(m, o, j, generation)) < 0)
257 static int transaction_verify_order(Manager *m, unsigned *generation) {
269 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
272 assert(!j->transaction_next);
273 assert(!j->transaction_prev);
275 if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0) {
277 /* There was a cycleq, but it was fixed,
278 * we need to restart our algorithm */
292 static void transaction_collect_garbage(Manager *m) {
303 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
307 manager_transaction_delete_job(m, j);
315 static int transaction_is_destructive(Manager *m, JobMode mode) {
321 /* Checks whether applying this transaction means that
322 * existing jobs would be replaced */
324 HASHMAP_FOREACH(j, m->transaction_jobs, state)
325 if (j->name->meta.job && j->name->meta.job != j)
331 static int transaction_apply(Manager *m, JobMode mode) {
336 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
340 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
344 while ((j = hashmap_steal_first(m->transaction_jobs))) {
348 if (j->name->meta.job)
349 job_free(j->name->meta.job);
351 j->name->meta.job = j;
354 /* We're fully installed. Now let's free data we don't
357 assert(!j->transaction_next);
358 assert(!j->transaction_prev);
360 while (j->subject_list)
361 job_dependency_free(j->subject_list);
362 while (j->object_list)
363 job_dependency_free(j->object_list);
370 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
374 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
381 static int transaction_activate(Manager *m, JobMode mode) {
383 unsigned generation = 1;
387 /* This applies the changes recorded in transaction_jobs to
388 * the actual list of jobs, if possible. */
390 /* First step: figure out which jobs matter */
391 transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
393 /* Second step: let's merge entries we can merge */
394 if ((r = transaction_merge_jobs(m)) < 0)
397 /* Third step: verify order makes sense */
398 if ((r = transaction_verify_order(m, &generation)) < 0)
401 /* Third step: do garbage colletion */
402 transaction_collect_garbage(m);
404 /* Fourth step: check whether we can actually apply this */
405 if (mode == JOB_FAIL)
406 if ((r = transaction_is_destructive(m, mode)) < 0)
409 /* Fifth step: apply changes */
410 if ((r = transaction_apply(m, mode)) < 0)
413 assert(hashmap_isempty(m->transaction_jobs));
414 assert(!m->transaction_anchor);
419 transaction_abort(m);
423 static Job* transaction_add_one_job(Manager *m, JobType type, Name *name, bool *is_new) {
430 /* Looks for an axisting prospective job and returns that. If
431 * it doesn't exist it is created and added to the prospective
434 f = hashmap_get(m->transaction_jobs, name);
436 for (j = f; j; j = j->transaction_next) {
437 assert(j->name == name);
439 if (j->type == type) {
446 if (name->meta.job && name->meta.job->type == type)
448 else if (!(j = job_new(m, type, name)))
451 if ((r = hashmap_replace(m->transaction_jobs, name, j)) < 0) {
456 j->transaction_next = f;
459 f->transaction_prev = j;
463 j->matters_to_anchor = false;
471 void manager_transaction_delete_job(Manager *m, Job *j) {
475 if (j->transaction_prev)
476 j->transaction_prev->transaction_next = j->transaction_next;
477 else if (j->transaction_next)
478 hashmap_replace(m->transaction_jobs, j->name, j->transaction_next);
480 hashmap_remove_value(m->transaction_jobs, j->name, j);
482 if (j->transaction_next)
483 j->transaction_next->transaction_prev = j->transaction_prev;
485 j->transaction_prev = j->transaction_next = NULL;
487 while (j->subject_list)
488 job_dependency_free(j->subject_list);
489 while (j->object_list)
490 job_dependency_free(j->object_list);
493 static int transaction_add_job_and_dependencies(Manager *m, JobType type, Name *name, Job *by, bool matters, bool force, Job **_ret) {
501 assert(type < _JOB_TYPE_MAX);
504 /* First add the job. */
505 if (!(ret = transaction_add_one_job(m, type, name, &is_new)))
508 /* Then, add a link to the job. */
509 if (!job_dependency_new(by, ret, matters))
513 /* Finally, recursively add in all dependencies. */
514 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
515 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRES], state)
516 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, force, NULL)) < 0)
518 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUIRES], state)
519 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !force, force, NULL)) < 0)
521 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_WANTS], state)
522 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, force, NULL)) < 0)
524 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUISITE], state)
525 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, true, force, NULL)) < 0)
527 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUISITE], state)
528 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, !force, force, NULL)) < 0)
530 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_CONFLICTS], state)
531 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, force, NULL)) < 0)
534 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
536 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRED_BY], state)
537 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, force, NULL)) < 0)
541 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
550 int manager_add_job(Manager *m, JobType type, Name *name, JobMode mode, bool force, Job **_ret) {
555 assert(type < _JOB_TYPE_MAX);
557 assert(mode < _JOB_MODE_MAX);
559 if ((r = transaction_add_job_and_dependencies(m, type, name, NULL, true, force, &ret))) {
560 transaction_abort(m);
564 if ((r = transaction_activate(m, mode)) < 0)
573 Job *manager_get_job(Manager *m, uint32_t id) {
576 return hashmap_get(m->jobs, UINT32_TO_PTR(id));
579 Name *manager_get_name(Manager *m, const char *name) {
583 return hashmap_get(m->names, name);
586 static int dispatch_load_queue(Manager *m) {
591 /* Make sure we are not run recursively */
592 if (m->dispatching_load_queue)
595 m->dispatching_load_queue = true;
597 /* Dispatches the load queue. Takes a name from the queue and
598 * tries to load its data until the queue is empty */
600 while ((meta = m->load_queue)) {
601 name_load(NAME(meta));
602 LIST_REMOVE(Meta, m->load_queue, meta);
605 m->dispatching_load_queue = false;
610 int manager_load_name(Manager *m, const char *name, Name **_ret) {
620 if (!name_is_valid(name))
623 /* This will load the service information files, but not actually
624 * start any services or anything */
626 if ((ret = manager_get_name(m, name)))
629 if ((t = name_type_from_string(name)) == _NAME_TYPE_INVALID)
632 if (!(ret = name_new(m)))
637 if (!(n = strdup(name))) {
642 if (set_put(ret->meta.names, n) < 0) {
648 if ((r = name_link(ret)) < 0) {
653 /* At this point the new entry is created and linked. However,
654 * not loaded. Now load this entry and all its dependencies
657 dispatch_load_queue(m);
665 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
672 HASHMAP_FOREACH(j, s->jobs, state)
673 job_dump(j, f, prefix);
676 void manager_dump_names(Manager *s, FILE *f, const char *prefix) {
684 HASHMAP_FOREACH_KEY(n, t, s->names, state)
686 name_dump(n, f, prefix);
689 void manager_clear_jobs(Manager *m) {
694 transaction_abort(m);
696 while ((j = hashmap_first(m->jobs)))