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extend test a little
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1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
2
3 #include <assert.h>
4 #include <errno.h>
5 #include <string.h>
6
7 #include "manager.h"
8 #include "hashmap.h"
9 #include "macro.h"
10 #include "strv.h"
11 #include "load-fragment.h"
12
13 Manager* manager_new(void) {
14 Manager *m;
15
16 if (!(m = new0(Manager, 1)))
17 return NULL;
18
19 if (!(m->names = hashmap_new(string_hash_func, string_compare_func)))
20 goto fail;
21
22 if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
23 goto fail;
24
25 if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
26 goto fail;
27
28 return m;
29
30 fail:
31 manager_free(m);
32 return NULL;
33 }
34
35 void manager_free(Manager *m) {
36 Name *n;
37 Job *j;
38
39 assert(m);
40
41 while ((n = hashmap_first(m->names)))
42 name_free(n);
43
44 while ((j = hashmap_steal_first(m->transaction_jobs)))
45 job_free(j);
46
47 hashmap_free(m->names);
48 hashmap_free(m->jobs);
49 hashmap_free(m->transaction_jobs);
50
51 free(m);
52 }
53
54 static void transaction_abort(Manager *m) {
55 Job *j;
56
57 assert(m);
58
59 while ((j = hashmap_first(m->transaction_jobs)))
60 if (j->linked)
61 manager_transaction_delete_job(m, j);
62 else
63 job_free(j);
64
65 assert(hashmap_isempty(m->transaction_jobs));
66 assert(!m->transaction_anchor);
67 }
68
69 static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
70 JobDependency *l;
71
72 assert(m);
73
74 for (l = j ? j->subject_list : m->transaction_anchor; l; l = l->subject_next) {
75
76 /* This link does not matter */
77 if (!l->matters)
78 continue;
79
80 /* This name has already been marked */
81 if (l->object->generation == generation)
82 continue;
83
84 l->object->matters_to_anchor = true;
85 l->object->generation = generation;
86
87 transaction_find_jobs_that_matter_to_anchor(m, l->object, generation);
88 }
89 }
90
91 static bool types_match(JobType a, JobType b, JobType c, JobType d) {
92 return
93 (a == c && b == d) ||
94 (a == d && b == c);
95 }
96
97 static int types_merge(JobType *a, JobType b) {
98 if (*a == b)
99 return 0;
100
101 if (types_match(*a, b, JOB_START, JOB_VERIFY_STARTED))
102 *a = JOB_START;
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))
115 *a = JOB_RESTART;
116 else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_RELOAD))
117 *a = 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;
121
122 return -EEXIST;
123 }
124
125 static void manager_merge_and_delete_prospective_job(Manager *m, Job *j, Job *other, JobType t) {
126 JobDependency *l, *last;
127
128 assert(j);
129 assert(other);
130 assert(j->name == other->name);
131 assert(!j->linked);
132
133 j->type = t;
134 j->state = JOB_WAITING;
135
136 j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor;
137
138 /* Patch us in as new owner of the JobDependency objects */
139 last = NULL;
140 for (l = other->subject_list; l; l = l->subject_next) {
141 assert(l->subject == other);
142 l->subject = j;
143 last = l;
144 }
145
146 /* Merge both lists */
147 if (last) {
148 last->subject_next = j->subject_list;
149 if (j->subject_list)
150 j->subject_list->subject_prev = last;
151 j->subject_list = other->subject_list;
152 }
153
154 /* Patch us in as new owner of the JobDependency objects */
155 last = NULL;
156 for (l = other->object_list; l; l = l->object_next) {
157 assert(l->object == other);
158 l->object = j;
159 last = l;
160 }
161
162 /* Merge both lists */
163 if (last) {
164 last->object_next = j->object_list;
165 if (j->object_list)
166 j->object_list->object_prev = last;
167 j->object_list = other->object_list;
168 }
169
170
171 /* Kill the other job */
172 other->subject_list = NULL;
173 other->object_list = NULL;
174 manager_transaction_delete_job(m, other);
175 }
176
177 static int transaction_merge_jobs(Manager *m) {
178 Job *j;
179 void *state;
180 int r;
181
182 assert(m);
183
184 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
185 JobType t = j->type;
186 Job *k;
187
188 for (k = j->transaction_next; k; k = k->transaction_next)
189 if ((r = types_merge(&t, k->type)) < 0)
190 return r;
191
192 while ((k = j->transaction_next)) {
193 if (j->linked) {
194 manager_merge_and_delete_prospective_job(m, k, j, t);
195 j = k;
196 } else
197 manager_merge_and_delete_prospective_job(m, j, k, t);
198 }
199
200 assert(!j->transaction_next);
201 assert(!j->transaction_prev);
202 }
203
204 return r;
205 }
206
207 static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation) {
208 void *state;
209 Name *n;
210 int r;
211
212 assert(m);
213 assert(j);
214
215 /* Did we find a loop? */
216 if (j->marker && j->generation == generation) {
217 Job *k;
218
219 /* So, we already have been here. We have a
220 * loop. Let's try to break it. We go backwards in our
221 * path and try to find a suitable job to remove. */
222
223 for (k = from; k; k = (k->generation == generation ? k->marker : NULL)) {
224 if (!k->matters_to_anchor) {
225 manager_transaction_delete_job(m, k);
226 return -EAGAIN;
227 }
228
229 /* Check if this in fact was the beginning of
230 * the loop */
231 if (k == j)
232 break;
233 }
234
235 return -ELOOP;
236 }
237
238 j->marker = from;
239 j->generation = generation;
240
241 /* We assume that the the dependencies are both-ways, and
242 * hence can ignore NAME_AFTER */
243
244 SET_FOREACH(n, j->name->meta.dependencies[NAME_BEFORE], state) {
245 Job *o;
246
247 if (!(o = hashmap_get(m->transaction_jobs, n)))
248 if (!(o = n->meta.job))
249 continue;
250
251 if ((r = transaction_verify_order_one(m, o, j, generation)) < 0)
252 return r;
253 }
254
255 return 0;
256 }
257
258 static int transaction_verify_order(Manager *m, unsigned *generation) {
259 bool again;
260 assert(m);
261 assert(generation);
262
263 do {
264 Job *j;
265 int r;
266 void *state;
267
268 again = false;
269
270 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
271
272 /* Assume merged */
273 assert(!j->transaction_next);
274 assert(!j->transaction_prev);
275
276 if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0) {
277
278 /* There was a loop, but it was fixed,
279 * we need to restart our algorithm */
280 if (r == -EAGAIN) {
281 again = true;
282 break;
283 }
284
285 return r;
286 }
287 }
288 } while (again);
289
290 return 0;
291 }
292
293 static void transaction_collect_garbage(Manager *m) {
294 bool again;
295
296 assert(m);
297
298 do {
299 void *state;
300 Job *j;
301
302 again = false;
303
304 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
305 if (j->object_list)
306 continue;
307
308 manager_transaction_delete_job(m, j);
309 again = true;
310 break;
311 }
312
313 } while (again);
314 }
315
316 static int transaction_is_destructive(Manager *m, JobMode mode) {
317 void *state;
318 Job *j;
319
320 assert(m);
321
322 /* Checks whether applying this transaction means that
323 * existing jobs would be replaced */
324
325 HASHMAP_FOREACH(j, m->transaction_jobs, state)
326 if (j->name->meta.job && j->name->meta.job != j)
327 return -EEXIST;
328
329 return 0;
330 }
331
332 static int transaction_apply(Manager *m, JobMode mode) {
333 void *state;
334 Job *j;
335 int r;
336
337 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
338 if (j->linked)
339 continue;
340
341 if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0)
342 goto rollback;
343 }
344
345 while ((j = hashmap_steal_first(m->transaction_jobs))) {
346 if (j->linked)
347 continue;
348
349 if (j->name->meta.job)
350 job_free(j->name->meta.job);
351
352 j->name->meta.job = j;
353 j->linked = true;
354
355 /* We're fully installed. Now let's free data we don't
356 * need anymore. */
357
358 assert(!j->transaction_next);
359 assert(!j->transaction_prev);
360
361 while (j->subject_list)
362 job_dependency_free(j->subject_list);
363 while (j->object_list)
364 job_dependency_free(j->object_list);
365 }
366
367 return 0;
368
369 rollback:
370
371 HASHMAP_FOREACH(j, m->transaction_jobs, state) {
372 if (j->linked)
373 continue;
374
375 hashmap_remove(m->jobs, UINT32_TO_PTR(j->id));
376 }
377
378 return r;
379 }
380
381
382 static int transaction_activate(Manager *m, JobMode mode) {
383 int r;
384 unsigned generation = 1;
385
386 assert(m);
387
388 /* This applies the changes recorded in transaction_jobs to
389 * the actual list of jobs, if possible. */
390
391 /* First step: figure out which jobs matter */
392 transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
393
394 /* Second step: let's merge entries we can merge */
395 if ((r = transaction_merge_jobs(m)) < 0)
396 goto rollback;
397
398 /* Third step: verify order makes sense */
399 if ((r = transaction_verify_order(m, &generation)) < 0)
400 goto rollback;
401
402 /* Third step: do garbage colletion */
403 transaction_collect_garbage(m);
404
405 /* Fourth step: check whether we can actually apply this */
406 if (mode == JOB_FAIL)
407 if ((r = transaction_is_destructive(m, mode)) < 0)
408 goto rollback;
409
410 /* Fifth step: apply changes */
411 if ((r = transaction_apply(m, mode)) < 0)
412 goto rollback;
413
414 assert(hashmap_isempty(m->transaction_jobs));
415 assert(!m->transaction_anchor);
416
417 return 0;
418
419 rollback:
420 transaction_abort(m);
421 return r;
422 }
423
424 static Job* transaction_add_one_job(Manager *m, JobType type, Name *name, bool *is_new) {
425 Job *j, *f;
426 int r;
427
428 assert(m);
429 assert(name);
430
431 /* Looks for an axisting prospective job and returns that. If
432 * it doesn't exist it is created and added to the prospective
433 * jobs list. */
434
435 f = hashmap_get(m->transaction_jobs, name);
436
437 for (j = f; j; j = j->transaction_next) {
438 assert(j->name == name);
439
440 if (j->type == type) {
441 if (is_new)
442 *is_new = false;
443 return j;
444 }
445 }
446
447 if (name->meta.job && name->meta.job->type == type)
448 j = name->meta.job;
449 else if (!(j = job_new(m, type, name)))
450 return NULL;
451
452 if ((r = hashmap_replace(m->transaction_jobs, name, j)) < 0) {
453 job_free(j);
454 return NULL;
455 }
456
457 j->transaction_next = f;
458
459 if (f)
460 f->transaction_prev = j;
461
462 j->generation = 0;
463 j->marker = NULL;
464 j->matters_to_anchor = false;
465
466 if (is_new)
467 *is_new = true;
468
469 return j;
470 }
471
472 void manager_transaction_delete_job(Manager *m, Job *j) {
473 assert(m);
474 assert(j);
475
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);
480 else
481 hashmap_remove_value(m->transaction_jobs, j->name, j);
482
483 if (j->transaction_next)
484 j->transaction_next->transaction_prev = j->transaction_prev;
485
486 j->transaction_prev = j->transaction_next = NULL;
487
488 while (j->subject_list)
489 job_dependency_free(j->subject_list);
490 while (j->object_list)
491 job_dependency_free(j->object_list);
492 }
493
494 static int transaction_add_job_and_dependencies(Manager *m, JobType type, Name *name, Job *by, bool matters, bool force, Job **_ret) {
495 Job *ret;
496 void *state;
497 Name *dep;
498 int r;
499 bool is_new;
500
501 assert(m);
502 assert(type < _JOB_TYPE_MAX);
503 assert(name);
504
505 /* First add the job. */
506 if (!(ret = transaction_add_one_job(m, type, name, &is_new)))
507 return -ENOMEM;
508
509 /* Then, add a link to the job. */
510 if (!job_dependency_new(by, ret, matters))
511 return -ENOMEM;
512
513 if (is_new) {
514 /* Finally, recursively add in all dependencies. */
515 if (type == JOB_START || type == JOB_RELOAD_OR_START) {
516 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRES], state)
517 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, force, NULL)) < 0)
518 goto fail;
519 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUIRES], state)
520 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !force, force, NULL)) < 0)
521 goto fail;
522 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_WANTS], state)
523 if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, force, NULL)) < 0)
524 goto fail;
525 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUISITE], state)
526 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, true, force, NULL)) < 0)
527 goto fail;
528 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUISITE], state)
529 if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, !force, force, NULL)) < 0)
530 goto fail;
531 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_CONFLICTS], state)
532 if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, force, NULL)) < 0)
533 goto fail;
534
535 } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
536
537 SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRED_BY], state)
538 if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, force, NULL)) < 0)
539 goto fail;
540 }
541
542 /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
543 }
544
545 return 0;
546
547 fail:
548 return r;
549 }
550
551 int manager_add_job(Manager *m, JobType type, Name *name, JobMode mode, bool force, Job **_ret) {
552 int r;
553 Job *ret;
554
555 assert(m);
556 assert(type < _JOB_TYPE_MAX);
557 assert(name);
558 assert(mode < _JOB_MODE_MAX);
559
560 if ((r = transaction_add_job_and_dependencies(m, type, name, NULL, true, force, &ret))) {
561 transaction_abort(m);
562 return r;
563 }
564
565 if ((r = transaction_activate(m, mode)) < 0)
566 return r;
567
568 if (_ret)
569 *_ret = ret;
570
571 return 0;
572 }
573
574 Job *manager_get_job(Manager *m, uint32_t id) {
575 assert(m);
576
577 return hashmap_get(m->jobs, UINT32_TO_PTR(id));
578 }
579
580 Name *manager_get_name(Manager *m, const char *name) {
581 assert(m);
582 assert(name);
583
584 return hashmap_get(m->names, name);
585 }
586
587 static int verify_type(Name *name) {
588 char *n;
589 void *state;
590
591 assert(name);
592
593 /* Checks that all aliases of this name have the same and valid type */
594
595 SET_FOREACH(n, name->meta.names, state) {
596 NameType t;
597
598 if ((t = name_type_from_string(n)) == _NAME_TYPE_INVALID)
599 return -EINVAL;
600
601 if (name->meta.type == _NAME_TYPE_INVALID) {
602 name->meta.type = t;
603 continue;
604 }
605
606 if (name->meta.type != t)
607 return -EINVAL;
608 }
609
610 if (name->meta.type == _NAME_TYPE_INVALID)
611 return -EINVAL;
612
613 return 0;
614 }
615
616 static int service_load_sysv(Service *s) {
617 assert(s);
618
619 /* Load service data from SysV init scripts, preferably with
620 * LSB headers ... */
621
622 return 0;
623 }
624
625 static int name_load_fstab(Name *n) {
626 assert(n);
627 assert(n->meta.type == NAME_MOUNT || n->meta.type == NAME_AUTOMOUNT);
628
629 /* Load mount data from /etc/fstab */
630
631 return 0;
632 }
633
634 static int snapshot_load(Snapshot *s) {
635 assert(s);
636
637 /* Load snapshots from disk */
638
639 return 0;
640 }
641
642 static int name_load_dropin(Name *n) {
643 assert(n);
644
645 /* Load dependencies from drop-in directories */
646
647 return 0;
648 }
649
650 static int load(Name *name) {
651 int r;
652
653 assert(name);
654
655 if (name->meta.state != NAME_STUB)
656 return 0;
657
658 if ((r = verify_type(name)) < 0)
659 return r;
660
661 if (name->meta.type == NAME_SERVICE) {
662
663 /* Load a .service file */
664 if ((r = name_load_fragment(name)) == 0)
665 goto finish;
666
667 /* Load a classic init script */
668 if (r == -ENOENT)
669 if ((r = service_load_sysv(SERVICE(name))) == 0)
670 goto finish;
671
672 } else if (name->meta.type == NAME_MOUNT ||
673 name->meta.type == NAME_AUTOMOUNT) {
674
675 if ((r = name_load_fstab(name)) == 0)
676 goto finish;
677
678 } else if (name->meta.type == NAME_SNAPSHOT) {
679
680 if ((r = snapshot_load(SNAPSHOT(name))) == 0)
681 goto finish;
682
683 } else {
684 if ((r = name_load_fragment(name)) == 0)
685 goto finish;
686 }
687
688 name->meta.state = NAME_FAILED;
689 return r;
690
691 finish:
692 if ((r = name_load_dropin(name)) < 0)
693 return r;
694
695 if ((r = name_link_names(name, true)) < 0)
696 return r;
697
698 name->meta.state = NAME_LOADED;
699 return 0;
700 }
701
702 static int dispatch_load_queue(Manager *m) {
703 Meta *meta;
704
705 assert(m);
706
707 /* Make sure we are not run recursively */
708 if (m->dispatching_load_queue)
709 return 0;
710
711 m->dispatching_load_queue = true;
712
713 /* Dispatches the load queue. Takes a name from the queue and
714 * tries to load its data until the queue is empty */
715
716 while ((meta = m->load_queue)) {
717 load(NAME(meta));
718 LIST_REMOVE(Meta, m->load_queue, meta);
719 }
720
721 m->dispatching_load_queue = false;
722
723 return 0;
724 }
725
726 int manager_load_name(Manager *m, const char *name, Name **_ret) {
727 Name *ret;
728 NameType t;
729 int r;
730 char *n;
731
732 assert(m);
733 assert(name);
734 assert(_ret);
735
736 if (!name_is_valid(name))
737 return -EINVAL;
738
739 /* This will load the service information files, but not actually
740 * start any services or anything */
741
742 if ((ret = manager_get_name(m, name)))
743 goto finish;
744
745 if ((t = name_type_from_string(name)) == _NAME_TYPE_INVALID)
746 return -EINVAL;
747
748 if (!(ret = name_new(m)))
749 return -ENOMEM;
750
751 ret->meta.type = t;
752
753 if (!(n = strdup(name))) {
754 name_free(ret);
755 return -ENOMEM;
756 }
757
758 if (set_put(ret->meta.names, n) < 0) {
759 name_free(ret);
760 free(n);
761 return -ENOMEM;
762 }
763
764 if ((r = name_link(ret)) < 0) {
765 name_free(ret);
766 return r;
767 }
768
769 /* At this point the new entry is created and linked. However,
770 * not loaded. Now load this entry and all its dependencies
771 * recursively */
772
773 dispatch_load_queue(m);
774
775 finish:
776
777 *_ret = ret;
778 return 0;
779 }
780
781 void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) {
782 void *state;
783 Job *j;
784
785 assert(s);
786 assert(f);
787
788 HASHMAP_FOREACH(j, s->jobs, state)
789 job_dump(j, f, prefix);
790 }
791
792 void manager_dump_names(Manager *s, FILE *f, const char *prefix) {
793 void *state;
794 Name *n;
795 const char *t;
796
797 assert(s);
798 assert(f);
799
800 HASHMAP_FOREACH_KEY(n, t, s->names, state)
801 if (name_id(n) == t)
802 name_dump(n, f, prefix);
803 }