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Commit | Line | Data |
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60918275 LP |
1 | /*-*- Mode: C; c-basic-offset: 8 -*-*/ |
2 | ||
3 | #include <assert.h> | |
4 | #include <errno.h> | |
87d1515d | 5 | #include <string.h> |
9152c765 LP |
6 | #include <sys/epoll.h> |
7 | #include <signal.h> | |
8 | #include <sys/signalfd.h> | |
9 | #include <sys/wait.h> | |
10 | #include <unistd.h> | |
11 | #include <sys/poll.h> | |
60918275 LP |
12 | |
13 | #include "manager.h" | |
14 | #include "hashmap.h" | |
15 | #include "macro.h" | |
16 | #include "strv.h" | |
16354eff | 17 | #include "log.h" |
60918275 LP |
18 | |
19 | Manager* manager_new(void) { | |
20 | Manager *m; | |
9152c765 LP |
21 | sigset_t mask; |
22 | struct epoll_event ev; | |
60918275 LP |
23 | |
24 | if (!(m = new0(Manager, 1))) | |
25 | return NULL; | |
26 | ||
9152c765 LP |
27 | m->signal_fd = m->epoll_fd = -1; |
28 | ||
60918275 LP |
29 | if (!(m->names = hashmap_new(string_hash_func, string_compare_func))) |
30 | goto fail; | |
31 | ||
32 | if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func))) | |
33 | goto fail; | |
34 | ||
e5b5ae50 | 35 | if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func))) |
60918275 LP |
36 | goto fail; |
37 | ||
9152c765 LP |
38 | if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func))) |
39 | goto fail; | |
40 | ||
41 | if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0) | |
42 | goto fail; | |
43 | ||
44 | assert_se(sigemptyset(&mask) == 0); | |
45 | assert_se(sigaddset(&mask, SIGCHLD) == 0); | |
46 | assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0); | |
47 | ||
48 | if ((m->signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0) | |
49 | goto fail; | |
50 | ||
51 | zero(ev); | |
52 | ev.events = EPOLLIN; | |
53 | ev.data.fd = m->signal_fd; | |
54 | ||
55 | if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_fd, &ev) < 0) | |
56 | goto fail; | |
57 | ||
60918275 LP |
58 | return m; |
59 | ||
60 | fail: | |
61 | manager_free(m); | |
62 | return NULL; | |
63 | } | |
64 | ||
65 | void manager_free(Manager *m) { | |
66 | Name *n; | |
e5b5ae50 | 67 | Job *j; |
60918275 LP |
68 | |
69 | assert(m); | |
70 | ||
71 | while ((n = hashmap_first(m->names))) | |
72 | name_free(n); | |
73 | ||
e5b5ae50 LP |
74 | while ((j = hashmap_steal_first(m->transaction_jobs))) |
75 | job_free(j); | |
76 | ||
60918275 LP |
77 | hashmap_free(m->names); |
78 | hashmap_free(m->jobs); | |
e5b5ae50 | 79 | hashmap_free(m->transaction_jobs); |
9152c765 LP |
80 | hashmap_free(m->watch_pids); |
81 | ||
82 | if (m->epoll_fd >= 0) | |
83 | close_nointr(m->epoll_fd); | |
84 | if (m->signal_fd >= 0) | |
85 | close_nointr(m->signal_fd); | |
60918275 LP |
86 | |
87 | free(m); | |
88 | } | |
89 | ||
302d0040 LP |
90 | static void transaction_delete_job(Manager *m, Job *j) { |
91 | assert(m); | |
92 | assert(j); | |
93 | ||
1ffba6fe LP |
94 | /* Deletes one job from the transaction */ |
95 | ||
302d0040 LP |
96 | manager_transaction_unlink_job(m, j); |
97 | ||
ac1135be | 98 | if (!j->installed) |
302d0040 LP |
99 | job_free(j); |
100 | } | |
101 | ||
1ffba6fe LP |
102 | static void transaction_delete_name(Manager *m, Name *n) { |
103 | Job *j; | |
104 | ||
105 | /* Deletes all jobs associated with a certain name from the | |
106 | * transaction */ | |
107 | ||
108 | while ((j = hashmap_get(m->transaction_jobs, n))) | |
109 | transaction_delete_job(m, j); | |
110 | } | |
111 | ||
11dd41ce LP |
112 | static void transaction_abort(Manager *m) { |
113 | Job *j; | |
114 | ||
115 | assert(m); | |
11dd41ce | 116 | |
e5b5ae50 | 117 | while ((j = hashmap_first(m->transaction_jobs))) |
ac1135be | 118 | if (j->installed) |
302d0040 | 119 | transaction_delete_job(m, j); |
e5b5ae50 LP |
120 | else |
121 | job_free(j); | |
122 | ||
123 | assert(hashmap_isempty(m->transaction_jobs)); | |
124 | assert(!m->transaction_anchor); | |
125 | } | |
126 | ||
127 | static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) { | |
128 | JobDependency *l; | |
129 | ||
130 | assert(m); | |
131 | ||
1ffba6fe LP |
132 | /* A recursive sweep through the graph that marks all names |
133 | * that matter to the anchor job, i.e. are directly or | |
134 | * indirectly a dependency of the anchor job via paths that | |
135 | * are fully marked as mattering. */ | |
136 | ||
44d8db9e LP |
137 | if (j) |
138 | l = j->subject_list; | |
139 | else | |
140 | l = m->transaction_anchor; | |
141 | ||
142 | LIST_FOREACH(subject, l, l) { | |
e5b5ae50 LP |
143 | |
144 | /* This link does not matter */ | |
145 | if (!l->matters) | |
146 | continue; | |
147 | ||
148 | /* This name has already been marked */ | |
149 | if (l->object->generation == generation) | |
150 | continue; | |
151 | ||
152 | l->object->matters_to_anchor = true; | |
153 | l->object->generation = generation; | |
154 | ||
155 | transaction_find_jobs_that_matter_to_anchor(m, l->object, generation); | |
156 | } | |
157 | } | |
158 | ||
7fad411c | 159 | static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) { |
e5b5ae50 LP |
160 | JobDependency *l, *last; |
161 | ||
162 | assert(j); | |
163 | assert(other); | |
164 | assert(j->name == other->name); | |
ac1135be | 165 | assert(!j->installed); |
e5b5ae50 | 166 | |
1ffba6fe LP |
167 | /* Merges 'other' into 'j' and then deletes j. */ |
168 | ||
e5b5ae50 LP |
169 | j->type = t; |
170 | j->state = JOB_WAITING; | |
5cb5a6ff | 171 | j->forced = j->forced || other->forced; |
e5b5ae50 LP |
172 | |
173 | j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor; | |
174 | ||
175 | /* Patch us in as new owner of the JobDependency objects */ | |
176 | last = NULL; | |
44d8db9e | 177 | LIST_FOREACH(subject, l, other->subject_list) { |
e5b5ae50 LP |
178 | assert(l->subject == other); |
179 | l->subject = j; | |
180 | last = l; | |
181 | } | |
182 | ||
183 | /* Merge both lists */ | |
184 | if (last) { | |
185 | last->subject_next = j->subject_list; | |
186 | if (j->subject_list) | |
187 | j->subject_list->subject_prev = last; | |
188 | j->subject_list = other->subject_list; | |
189 | } | |
190 | ||
191 | /* Patch us in as new owner of the JobDependency objects */ | |
192 | last = NULL; | |
44d8db9e | 193 | LIST_FOREACH(object, l, other->object_list) { |
e5b5ae50 LP |
194 | assert(l->object == other); |
195 | l->object = j; | |
196 | last = l; | |
197 | } | |
198 | ||
199 | /* Merge both lists */ | |
200 | if (last) { | |
201 | last->object_next = j->object_list; | |
202 | if (j->object_list) | |
203 | j->object_list->object_prev = last; | |
204 | j->object_list = other->object_list; | |
205 | } | |
206 | ||
e5b5ae50 LP |
207 | /* Kill the other job */ |
208 | other->subject_list = NULL; | |
209 | other->object_list = NULL; | |
302d0040 | 210 | transaction_delete_job(m, other); |
e5b5ae50 LP |
211 | } |
212 | ||
5cb5a6ff | 213 | static int delete_one_unmergeable_job(Manager *m, Job *j) { |
1ffba6fe LP |
214 | Job *k; |
215 | ||
216 | assert(j); | |
217 | ||
218 | /* Tries to delete one item in the linked list | |
219 | * j->transaction_next->transaction_next->... that conflicts | |
220 | * whith another one, in an attempt to make an inconsistent | |
221 | * transaction work. */ | |
222 | ||
223 | /* We rely here on the fact that if a merged with b does not | |
224 | * merge with c, either a or b merge with c neither */ | |
034c6ed7 LP |
225 | LIST_FOREACH(transaction, j, j) |
226 | LIST_FOREACH(transaction, k, j->transaction_next) { | |
1ffba6fe LP |
227 | Job *d; |
228 | ||
229 | /* Is this one mergeable? Then skip it */ | |
5cb5a6ff | 230 | if (job_type_is_mergeable(j->type, k->type)) |
1ffba6fe LP |
231 | continue; |
232 | ||
233 | /* Ok, we found two that conflict, let's see if we can | |
234 | * drop one of them */ | |
235 | if (!j->matters_to_anchor) | |
236 | d = j; | |
237 | else if (!k->matters_to_anchor) | |
238 | d = k; | |
239 | else | |
240 | return -ENOEXEC; | |
241 | ||
242 | /* Ok, we can drop one, so let's do so. */ | |
5cb5a6ff | 243 | log_debug("Try to fix job merging by deleting job %s/%s", name_id(d->name), job_type_to_string(d->type)); |
1ffba6fe LP |
244 | transaction_delete_job(m, d); |
245 | return 0; | |
246 | } | |
247 | ||
248 | return -EINVAL; | |
249 | } | |
250 | ||
e5b5ae50 | 251 | static int transaction_merge_jobs(Manager *m) { |
11dd41ce | 252 | Job *j; |
034c6ed7 | 253 | Iterator i; |
e5b5ae50 LP |
254 | int r; |
255 | ||
256 | assert(m); | |
257 | ||
1ffba6fe LP |
258 | /* First step, check whether any of the jobs for one specific |
259 | * task conflict. If so, try to drop one of them. */ | |
034c6ed7 | 260 | HASHMAP_FOREACH(j, m->transaction_jobs, i) { |
1ffba6fe LP |
261 | JobType t; |
262 | Job *k; | |
263 | ||
264 | t = j->type; | |
034c6ed7 | 265 | LIST_FOREACH(transaction, k, j->transaction_next) { |
1ffba6fe LP |
266 | if ((r = job_type_merge(&t, k->type)) >= 0) |
267 | continue; | |
268 | ||
269 | /* OK, we could not merge all jobs for this | |
270 | * action. Let's see if we can get rid of one | |
271 | * of them */ | |
272 | ||
5cb5a6ff | 273 | if ((r = delete_one_unmergeable_job(m, j)) >= 0) |
1ffba6fe LP |
274 | /* Ok, we managed to drop one, now |
275 | * let's ask our callers to call us | |
276 | * again after garbage collecting */ | |
277 | return -EAGAIN; | |
278 | ||
279 | /* We couldn't merge anything. Failure */ | |
280 | return r; | |
281 | } | |
282 | } | |
283 | ||
284 | /* Second step, merge the jobs. */ | |
034c6ed7 | 285 | HASHMAP_FOREACH(j, m->transaction_jobs, i) { |
e5b5ae50 LP |
286 | JobType t = j->type; |
287 | Job *k; | |
288 | ||
e094e853 | 289 | /* Merge all transactions */ |
034c6ed7 | 290 | LIST_FOREACH(transaction, k, j->transaction_next) |
1ffba6fe | 291 | assert_se(job_type_merge(&t, k->type) == 0); |
e5b5ae50 | 292 | |
5cb5a6ff | 293 | /* If an active job is mergeable, merge it too */ |
e094e853 LP |
294 | if (j->name->meta.job) |
295 | job_type_merge(&t, j->name->meta.job->type); /* Might fail. Which is OK */ | |
296 | ||
e5b5ae50 | 297 | while ((k = j->transaction_next)) { |
ac1135be | 298 | if (j->installed) { |
7fad411c | 299 | transaction_merge_and_delete_job(m, k, j, t); |
e5b5ae50 LP |
300 | j = k; |
301 | } else | |
7fad411c | 302 | transaction_merge_and_delete_job(m, j, k, t); |
e5b5ae50 LP |
303 | } |
304 | ||
305 | assert(!j->transaction_next); | |
306 | assert(!j->transaction_prev); | |
307 | } | |
308 | ||
7fad411c | 309 | return 0; |
e5b5ae50 LP |
310 | } |
311 | ||
1ffba6fe LP |
312 | static bool name_matters_to_anchor(Name *n, Job *j) { |
313 | assert(n); | |
314 | assert(!j->transaction_prev); | |
315 | ||
316 | /* Checks whether at least one of the jobs for this name | |
317 | * matters to the anchor. */ | |
318 | ||
034c6ed7 | 319 | LIST_FOREACH(transaction, j, j) |
1ffba6fe LP |
320 | if (j->matters_to_anchor) |
321 | return true; | |
322 | ||
323 | return false; | |
324 | } | |
325 | ||
e5b5ae50 | 326 | static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation) { |
034c6ed7 | 327 | Iterator i; |
e5b5ae50 | 328 | Name *n; |
11dd41ce | 329 | int r; |
e5b5ae50 LP |
330 | |
331 | assert(m); | |
332 | assert(j); | |
1ffba6fe LP |
333 | assert(!j->transaction_prev); |
334 | ||
335 | /* Does a recursive sweep through the ordering graph, looking | |
336 | * for a cycle. If we find cycle we try to break it. */ | |
e5b5ae50 | 337 | |
7fad411c | 338 | /* Did we find a cycle? */ |
e5b5ae50 LP |
339 | if (j->marker && j->generation == generation) { |
340 | Job *k; | |
341 | ||
342 | /* So, we already have been here. We have a | |
1ffba6fe LP |
343 | * cycle. Let's try to break it. We go backwards in |
344 | * our path and try to find a suitable job to | |
345 | * remove. We use the marker to find our way back, | |
346 | * since smart how we are we stored our way back in | |
347 | * there. */ | |
e5b5ae50 LP |
348 | |
349 | for (k = from; k; k = (k->generation == generation ? k->marker : NULL)) { | |
1ffba6fe | 350 | |
ac1135be | 351 | if (!k->installed && |
1ffba6fe LP |
352 | !name_matters_to_anchor(k->name, k)) { |
353 | /* Ok, we can drop this one, so let's | |
354 | * do so. */ | |
5cb5a6ff | 355 | log_debug("Breaking order cycle by deleting job %s/%s", name_id(k->name), job_type_to_string(k->type)); |
1ffba6fe | 356 | transaction_delete_name(m, k->name); |
e5b5ae50 LP |
357 | return -EAGAIN; |
358 | } | |
359 | ||
360 | /* Check if this in fact was the beginning of | |
7fad411c | 361 | * the cycle */ |
e5b5ae50 LP |
362 | if (k == j) |
363 | break; | |
364 | } | |
365 | ||
1ffba6fe | 366 | return -ENOEXEC; |
e5b5ae50 LP |
367 | } |
368 | ||
1ffba6fe LP |
369 | /* Make the marker point to where we come from, so that we can |
370 | * find our way backwards if we want to break a cycle */ | |
e5b5ae50 LP |
371 | j->marker = from; |
372 | j->generation = generation; | |
373 | ||
1ffba6fe | 374 | /* We assume that the the dependencies are bidirectional, and |
e5b5ae50 | 375 | * hence can ignore NAME_AFTER */ |
034c6ed7 | 376 | SET_FOREACH(n, j->name->meta.dependencies[NAME_BEFORE], i) { |
e5b5ae50 LP |
377 | Job *o; |
378 | ||
1ffba6fe | 379 | /* Is there a job for this name? */ |
e5b5ae50 | 380 | if (!(o = hashmap_get(m->transaction_jobs, n))) |
1ffba6fe LP |
381 | |
382 | /* Ok, there is no job for this in the | |
383 | * transaction, but maybe there is already one | |
384 | * running? */ | |
e5b5ae50 LP |
385 | if (!(o = n->meta.job)) |
386 | continue; | |
387 | ||
388 | if ((r = transaction_verify_order_one(m, o, j, generation)) < 0) | |
389 | return r; | |
390 | } | |
391 | ||
392 | return 0; | |
393 | } | |
394 | ||
395 | static int transaction_verify_order(Manager *m, unsigned *generation) { | |
1ffba6fe LP |
396 | Job *j; |
397 | int r; | |
034c6ed7 | 398 | Iterator i; |
1ffba6fe | 399 | |
e5b5ae50 LP |
400 | assert(m); |
401 | assert(generation); | |
402 | ||
1ffba6fe LP |
403 | /* Check if the ordering graph is cyclic. If it is, try to fix |
404 | * that up by dropping one of the jobs. */ | |
e5b5ae50 | 405 | |
034c6ed7 | 406 | HASHMAP_FOREACH(j, m->transaction_jobs, i) |
1ffba6fe LP |
407 | if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0) |
408 | return r; | |
e5b5ae50 LP |
409 | |
410 | return 0; | |
411 | } | |
412 | ||
413 | static void transaction_collect_garbage(Manager *m) { | |
414 | bool again; | |
415 | ||
416 | assert(m); | |
417 | ||
1ffba6fe LP |
418 | /* Drop jobs that are not required by any other job */ |
419 | ||
e5b5ae50 | 420 | do { |
034c6ed7 | 421 | Iterator i; |
e5b5ae50 LP |
422 | Job *j; |
423 | ||
424 | again = false; | |
425 | ||
034c6ed7 | 426 | HASHMAP_FOREACH(j, m->transaction_jobs, i) { |
e5b5ae50 LP |
427 | if (j->object_list) |
428 | continue; | |
429 | ||
5cb5a6ff | 430 | log_debug("Garbage collecting job %s/%s", name_id(j->name), job_type_to_string(j->type)); |
302d0040 | 431 | transaction_delete_job(m, j); |
e5b5ae50 LP |
432 | again = true; |
433 | break; | |
434 | } | |
435 | ||
436 | } while (again); | |
437 | } | |
438 | ||
439 | static int transaction_is_destructive(Manager *m, JobMode mode) { | |
034c6ed7 | 440 | Iterator i; |
e5b5ae50 | 441 | Job *j; |
11dd41ce LP |
442 | |
443 | assert(m); | |
11dd41ce | 444 | |
e5b5ae50 LP |
445 | /* Checks whether applying this transaction means that |
446 | * existing jobs would be replaced */ | |
11dd41ce | 447 | |
034c6ed7 | 448 | HASHMAP_FOREACH(j, m->transaction_jobs, i) { |
e094e853 LP |
449 | |
450 | /* Assume merged */ | |
451 | assert(!j->transaction_prev); | |
452 | assert(!j->transaction_next); | |
453 | ||
1ffba6fe LP |
454 | if (j->name->meta.job && |
455 | j->name->meta.job != j && | |
456 | !job_type_is_superset(j->type, j->name->meta.job->type)) | |
e5b5ae50 | 457 | return -EEXIST; |
e094e853 | 458 | } |
11dd41ce | 459 | |
e5b5ae50 LP |
460 | return 0; |
461 | } | |
462 | ||
e094e853 LP |
463 | static void transaction_minimize_impact(Manager *m) { |
464 | bool again; | |
465 | assert(m); | |
466 | ||
467 | /* Drops all unnecessary jobs that reverse already active jobs | |
468 | * or that stop a running service. */ | |
469 | ||
470 | do { | |
471 | Job *j; | |
034c6ed7 | 472 | Iterator i; |
e094e853 LP |
473 | |
474 | again = false; | |
475 | ||
034c6ed7 LP |
476 | HASHMAP_FOREACH(j, m->transaction_jobs, i) { |
477 | LIST_FOREACH(transaction, j, j) { | |
e094e853 LP |
478 | |
479 | /* If it matters, we shouldn't drop it */ | |
480 | if (j->matters_to_anchor) | |
481 | continue; | |
482 | ||
483 | /* Would this stop a running service? | |
484 | * Would this change an existing job? | |
485 | * If so, let's drop this entry */ | |
5cb5a6ff | 486 | if ((j->type != JOB_STOP || NAME_IS_INACTIVE_OR_DEACTIVATING(name_active_state(j->name))) && |
e094e853 LP |
487 | (!j->name->meta.job || job_type_is_conflicting(j->type, j->name->meta.job->state))) |
488 | continue; | |
489 | ||
490 | /* Ok, let's get rid of this */ | |
5cb5a6ff | 491 | log_debug("Deleting %s/%s to minimize impact", name_id(j->name), job_type_to_string(j->type)); |
e094e853 LP |
492 | transaction_delete_job(m, j); |
493 | again = true; | |
494 | break; | |
495 | } | |
496 | ||
497 | if (again) | |
498 | break; | |
499 | } | |
500 | ||
501 | } while (again); | |
502 | } | |
503 | ||
e5b5ae50 | 504 | static int transaction_apply(Manager *m, JobMode mode) { |
034c6ed7 | 505 | Iterator i; |
e5b5ae50 LP |
506 | Job *j; |
507 | int r; | |
508 | ||
1ffba6fe LP |
509 | /* Moves the transaction jobs to the set of active jobs */ |
510 | ||
034c6ed7 | 511 | HASHMAP_FOREACH(j, m->transaction_jobs, i) { |
e094e853 LP |
512 | /* Assume merged */ |
513 | assert(!j->transaction_prev); | |
514 | assert(!j->transaction_next); | |
515 | ||
ac1135be | 516 | if (j->installed) |
e5b5ae50 LP |
517 | continue; |
518 | ||
519 | if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0) | |
11dd41ce LP |
520 | goto rollback; |
521 | } | |
522 | ||
e5b5ae50 | 523 | while ((j = hashmap_steal_first(m->transaction_jobs))) { |
ac1135be | 524 | if (j->installed) |
e5b5ae50 LP |
525 | continue; |
526 | ||
527 | if (j->name->meta.job) | |
528 | job_free(j->name->meta.job); | |
11dd41ce | 529 | |
11dd41ce | 530 | j->name->meta.job = j; |
ac1135be | 531 | j->installed = true; |
11dd41ce | 532 | |
e5b5ae50 LP |
533 | /* We're fully installed. Now let's free data we don't |
534 | * need anymore. */ | |
535 | ||
536 | assert(!j->transaction_next); | |
537 | assert(!j->transaction_prev); | |
538 | ||
539 | while (j->subject_list) | |
540 | job_dependency_free(j->subject_list); | |
541 | while (j->object_list) | |
542 | job_dependency_free(j->object_list); | |
543 | } | |
11dd41ce | 544 | |
1ffba6fe LP |
545 | m->transaction_anchor = NULL; |
546 | ||
11dd41ce LP |
547 | return 0; |
548 | ||
549 | rollback: | |
550 | ||
034c6ed7 | 551 | HASHMAP_FOREACH(j, m->transaction_jobs, i) { |
ac1135be | 552 | if (j->installed) |
e5b5ae50 LP |
553 | continue; |
554 | ||
555 | hashmap_remove(m->jobs, UINT32_TO_PTR(j->id)); | |
556 | } | |
557 | ||
558 | return r; | |
559 | } | |
560 | ||
e5b5ae50 LP |
561 | static int transaction_activate(Manager *m, JobMode mode) { |
562 | int r; | |
563 | unsigned generation = 1; | |
564 | ||
565 | assert(m); | |
566 | ||
567 | /* This applies the changes recorded in transaction_jobs to | |
568 | * the actual list of jobs, if possible. */ | |
569 | ||
570 | /* First step: figure out which jobs matter */ | |
571 | transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++); | |
572 | ||
e094e853 LP |
573 | /* Second step: Try not to stop any running services if |
574 | * we don't have to. Don't try to reverse running | |
575 | * jobs if we don't have to. */ | |
576 | transaction_minimize_impact(m); | |
577 | ||
1ffba6fe | 578 | for (;;) { |
e094e853 | 579 | /* Third step: Let's remove unneeded jobs that might |
1ffba6fe LP |
580 | * be lurking. */ |
581 | transaction_collect_garbage(m); | |
e5b5ae50 | 582 | |
e094e853 | 583 | /* Fourth step: verify order makes sense and correct |
1ffba6fe LP |
584 | * cycles if necessary and possible */ |
585 | if ((r = transaction_verify_order(m, &generation)) >= 0) | |
586 | break; | |
e5b5ae50 | 587 | |
1ffba6fe LP |
588 | if (r != -EAGAIN) |
589 | goto rollback; | |
e5b5ae50 | 590 | |
1ffba6fe LP |
591 | /* Let's see if the resulting transaction ordering |
592 | * graph is still cyclic... */ | |
593 | } | |
594 | ||
595 | for (;;) { | |
5cb5a6ff | 596 | /* Fifth step: let's drop unmergeable entries if |
1ffba6fe LP |
597 | * necessary and possible, merge entries we can |
598 | * merge */ | |
599 | if ((r = transaction_merge_jobs(m)) >= 0) | |
600 | break; | |
601 | ||
602 | if (r != -EAGAIN) | |
603 | goto rollback; | |
604 | ||
e094e853 | 605 | /* Sixth step: an entry got dropped, let's garbage |
1ffba6fe LP |
606 | * collect its dependencies. */ |
607 | transaction_collect_garbage(m); | |
608 | ||
609 | /* Let's see if the resulting transaction still has | |
5cb5a6ff | 610 | * unmergeable entries ... */ |
1ffba6fe LP |
611 | } |
612 | ||
e094e853 | 613 | /* Seventh step: check whether we can actually apply this */ |
e5b5ae50 LP |
614 | if (mode == JOB_FAIL) |
615 | if ((r = transaction_is_destructive(m, mode)) < 0) | |
616 | goto rollback; | |
617 | ||
e094e853 | 618 | /* Eights step: apply changes */ |
e5b5ae50 LP |
619 | if ((r = transaction_apply(m, mode)) < 0) |
620 | goto rollback; | |
621 | ||
622 | assert(hashmap_isempty(m->transaction_jobs)); | |
623 | assert(!m->transaction_anchor); | |
624 | ||
625 | return 0; | |
11dd41ce | 626 | |
e5b5ae50 | 627 | rollback: |
11dd41ce LP |
628 | transaction_abort(m); |
629 | return r; | |
630 | } | |
631 | ||
5cb5a6ff | 632 | static Job* transaction_add_one_job(Manager *m, JobType type, Name *name, bool force, bool *is_new) { |
e5b5ae50 | 633 | Job *j, *f; |
60918275 LP |
634 | int r; |
635 | ||
636 | assert(m); | |
60918275 | 637 | assert(name); |
60918275 | 638 | |
e5b5ae50 LP |
639 | /* Looks for an axisting prospective job and returns that. If |
640 | * it doesn't exist it is created and added to the prospective | |
641 | * jobs list. */ | |
60918275 | 642 | |
e5b5ae50 | 643 | f = hashmap_get(m->transaction_jobs, name); |
60918275 | 644 | |
034c6ed7 | 645 | LIST_FOREACH(transaction, j, f) { |
e5b5ae50 | 646 | assert(j->name == name); |
60918275 | 647 | |
e5b5ae50 LP |
648 | if (j->type == type) { |
649 | if (is_new) | |
650 | *is_new = false; | |
651 | return j; | |
652 | } | |
653 | } | |
60918275 | 654 | |
e5b5ae50 LP |
655 | if (name->meta.job && name->meta.job->type == type) |
656 | j = name->meta.job; | |
657 | else if (!(j = job_new(m, type, name))) | |
658 | return NULL; | |
60918275 | 659 | |
e5b5ae50 LP |
660 | j->generation = 0; |
661 | j->marker = NULL; | |
662 | j->matters_to_anchor = false; | |
5cb5a6ff | 663 | j->forced = force; |
60918275 | 664 | |
034c6ed7 LP |
665 | LIST_PREPEND(Job, transaction, f, j); |
666 | ||
667 | if ((r = hashmap_replace(m->transaction_jobs, name, f)) < 0) { | |
668 | job_free(j); | |
669 | return NULL; | |
670 | } | |
671 | ||
e5b5ae50 LP |
672 | if (is_new) |
673 | *is_new = true; | |
60918275 | 674 | |
e5b5ae50 LP |
675 | return j; |
676 | } | |
11dd41ce | 677 | |
302d0040 | 678 | void manager_transaction_unlink_job(Manager *m, Job *j) { |
e5b5ae50 LP |
679 | assert(m); |
680 | assert(j); | |
11dd41ce | 681 | |
e5b5ae50 LP |
682 | if (j->transaction_prev) |
683 | j->transaction_prev->transaction_next = j->transaction_next; | |
684 | else if (j->transaction_next) | |
685 | hashmap_replace(m->transaction_jobs, j->name, j->transaction_next); | |
686 | else | |
687 | hashmap_remove_value(m->transaction_jobs, j->name, j); | |
688 | ||
689 | if (j->transaction_next) | |
690 | j->transaction_next->transaction_prev = j->transaction_prev; | |
691 | ||
692 | j->transaction_prev = j->transaction_next = NULL; | |
693 | ||
694 | while (j->subject_list) | |
695 | job_dependency_free(j->subject_list); | |
1e198baf LP |
696 | |
697 | while (j->object_list) { | |
698 | Job *other = j->object_list->matters ? j->object_list->subject : NULL; | |
699 | ||
e5b5ae50 | 700 | job_dependency_free(j->object_list); |
1e198baf LP |
701 | |
702 | if (other) { | |
5cb5a6ff LP |
703 | log_debug("Deleting job %s/%s as dependency of job %s/%s", |
704 | name_id(other->name), job_type_to_string(other->type), | |
705 | name_id(j->name), job_type_to_string(j->type)); | |
302d0040 | 706 | transaction_delete_job(m, other); |
1e198baf LP |
707 | } |
708 | } | |
e5b5ae50 LP |
709 | } |
710 | ||
ceed3570 | 711 | static int transaction_add_job_and_dependencies(Manager *m, JobType type, Name *name, Job *by, bool matters, bool force, Job **_ret) { |
e5b5ae50 | 712 | Job *ret; |
034c6ed7 | 713 | Iterator i; |
e5b5ae50 LP |
714 | Name *dep; |
715 | int r; | |
716 | bool is_new; | |
717 | ||
718 | assert(m); | |
719 | assert(type < _JOB_TYPE_MAX); | |
720 | assert(name); | |
721 | ||
5cb5a6ff | 722 | if (name->meta.load_state != NAME_LOADED) |
21b293e8 LP |
723 | return -EINVAL; |
724 | ||
034c6ed7 | 725 | if (!name_job_is_applicable(name, type)) |
cd2dbd7d LP |
726 | return -EBADR; |
727 | ||
e5b5ae50 | 728 | /* First add the job. */ |
5cb5a6ff | 729 | if (!(ret = transaction_add_one_job(m, type, name, force, &is_new))) |
e5b5ae50 LP |
730 | return -ENOMEM; |
731 | ||
732 | /* Then, add a link to the job. */ | |
733 | if (!job_dependency_new(by, ret, matters)) | |
734 | return -ENOMEM; | |
735 | ||
736 | if (is_new) { | |
737 | /* Finally, recursively add in all dependencies. */ | |
738 | if (type == JOB_START || type == JOB_RELOAD_OR_START) { | |
034c6ed7 | 739 | SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRES], i) |
542563ba | 740 | if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, force, NULL)) < 0 && r != -EBADR) |
e5b5ae50 | 741 | goto fail; |
034c6ed7 | 742 | SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUIRES], i) |
542563ba | 743 | if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !force, force, NULL)) < 0 && r != -EBADR) |
e5b5ae50 | 744 | goto fail; |
034c6ed7 | 745 | SET_FOREACH(dep, ret->name->meta.dependencies[NAME_WANTS], i) |
542563ba | 746 | if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, force, NULL)) < 0 && r != -EBADR) |
e5b5ae50 | 747 | goto fail; |
034c6ed7 | 748 | SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUISITE], i) |
542563ba | 749 | if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, force, NULL)) < 0 && r != -EBADR) |
e5b5ae50 | 750 | goto fail; |
034c6ed7 | 751 | SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUISITE], i) |
542563ba | 752 | if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !force, force, NULL)) < 0 && r != -EBADR) |
e5b5ae50 | 753 | goto fail; |
034c6ed7 | 754 | SET_FOREACH(dep, ret->name->meta.dependencies[NAME_CONFLICTS], i) |
542563ba | 755 | if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, force, NULL)) < 0 && r != -EBADR) |
e5b5ae50 LP |
756 | goto fail; |
757 | ||
758 | } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) { | |
759 | ||
034c6ed7 | 760 | SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRED_BY], i) |
542563ba | 761 | if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, force, NULL)) < 0 && r != -EBADR) |
e5b5ae50 LP |
762 | goto fail; |
763 | } | |
764 | ||
765 | /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */ | |
766 | } | |
60918275 LP |
767 | |
768 | return 0; | |
769 | ||
770 | fail: | |
e5b5ae50 LP |
771 | return r; |
772 | } | |
773 | ||
774 | int manager_add_job(Manager *m, JobType type, Name *name, JobMode mode, bool force, Job **_ret) { | |
775 | int r; | |
776 | Job *ret; | |
777 | ||
778 | assert(m); | |
779 | assert(type < _JOB_TYPE_MAX); | |
780 | assert(name); | |
781 | assert(mode < _JOB_MODE_MAX); | |
60918275 | 782 | |
ceed3570 | 783 | if ((r = transaction_add_job_and_dependencies(m, type, name, NULL, true, force, &ret))) { |
11dd41ce | 784 | transaction_abort(m); |
e5b5ae50 LP |
785 | return r; |
786 | } | |
11dd41ce | 787 | |
e5b5ae50 LP |
788 | if ((r = transaction_activate(m, mode)) < 0) |
789 | return r; | |
790 | ||
791 | if (_ret) | |
792 | *_ret = ret; | |
60918275 | 793 | |
e5b5ae50 LP |
794 | return 0; |
795 | } | |
60918275 LP |
796 | |
797 | Job *manager_get_job(Manager *m, uint32_t id) { | |
798 | assert(m); | |
799 | ||
800 | return hashmap_get(m->jobs, UINT32_TO_PTR(id)); | |
801 | } | |
802 | ||
803 | Name *manager_get_name(Manager *m, const char *name) { | |
804 | assert(m); | |
805 | assert(name); | |
806 | ||
807 | return hashmap_get(m->names, name); | |
808 | } | |
809 | ||
034c6ed7 | 810 | static void dispatch_load_queue(Manager *m) { |
60918275 LP |
811 | Meta *meta; |
812 | ||
813 | assert(m); | |
814 | ||
223dabab LP |
815 | /* Make sure we are not run recursively */ |
816 | if (m->dispatching_load_queue) | |
034c6ed7 | 817 | return; |
223dabab LP |
818 | |
819 | m->dispatching_load_queue = true; | |
820 | ||
60918275 LP |
821 | /* Dispatches the load queue. Takes a name from the queue and |
822 | * tries to load its data until the queue is empty */ | |
823 | ||
824 | while ((meta = m->load_queue)) { | |
034c6ed7 LP |
825 | assert(meta->in_load_queue); |
826 | ||
7fad411c | 827 | name_load(NAME(meta)); |
60918275 LP |
828 | } |
829 | ||
223dabab | 830 | m->dispatching_load_queue = false; |
60918275 LP |
831 | } |
832 | ||
60918275 LP |
833 | int manager_load_name(Manager *m, const char *name, Name **_ret) { |
834 | Name *ret; | |
60918275 LP |
835 | int r; |
836 | ||
837 | assert(m); | |
838 | assert(name); | |
839 | assert(_ret); | |
60918275 | 840 | |
223dabab LP |
841 | /* This will load the service information files, but not actually |
842 | * start any services or anything */ | |
60918275 | 843 | |
034c6ed7 LP |
844 | if ((ret = manager_get_name(m, name))) { |
845 | *_ret = ret; | |
846 | return 0; | |
847 | } | |
60918275 LP |
848 | |
849 | if (!(ret = name_new(m))) | |
850 | return -ENOMEM; | |
851 | ||
034c6ed7 | 852 | if ((r = name_add_name(ret, name)) < 0) { |
87d1515d | 853 | name_free(ret); |
1ffba6fe | 854 | return r; |
60918275 LP |
855 | } |
856 | ||
ac1135be | 857 | name_add_to_load_queue(ret); |
60918275 LP |
858 | dispatch_load_queue(m); |
859 | ||
60918275 LP |
860 | *_ret = ret; |
861 | return 0; | |
862 | } | |
a66d02c3 | 863 | |
cea8e32e | 864 | void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) { |
034c6ed7 | 865 | Iterator i; |
a66d02c3 LP |
866 | Job *j; |
867 | ||
868 | assert(s); | |
869 | assert(f); | |
870 | ||
034c6ed7 | 871 | HASHMAP_FOREACH(j, s->jobs, i) |
cea8e32e | 872 | job_dump(j, f, prefix); |
a66d02c3 LP |
873 | } |
874 | ||
cea8e32e | 875 | void manager_dump_names(Manager *s, FILE *f, const char *prefix) { |
034c6ed7 | 876 | Iterator i; |
a66d02c3 | 877 | Name *n; |
11dd41ce | 878 | const char *t; |
a66d02c3 LP |
879 | |
880 | assert(s); | |
881 | assert(f); | |
882 | ||
034c6ed7 | 883 | HASHMAP_FOREACH_KEY(n, t, s->names, i) |
11dd41ce | 884 | if (name_id(n) == t) |
cea8e32e | 885 | name_dump(n, f, prefix); |
a66d02c3 | 886 | } |
7fad411c LP |
887 | |
888 | void manager_clear_jobs(Manager *m) { | |
889 | Job *j; | |
890 | ||
891 | assert(m); | |
892 | ||
893 | transaction_abort(m); | |
894 | ||
895 | while ((j = hashmap_first(m->jobs))) | |
896 | job_free(j); | |
897 | } | |
83c60c9f | 898 | |
034c6ed7 | 899 | void manager_dispatch_run_queue(Manager *m) { |
83c60c9f | 900 | Job *j; |
83c60c9f | 901 | |
034c6ed7 LP |
902 | if (m->dispatching_run_queue) |
903 | return; | |
904 | ||
905 | m->dispatching_run_queue = true; | |
9152c765 | 906 | |
034c6ed7 | 907 | while ((j = m->run_queue)) { |
ac1135be | 908 | assert(j->installed); |
034c6ed7 LP |
909 | assert(j->in_run_queue); |
910 | ||
911 | job_run_and_invalidate(j); | |
9152c765 | 912 | } |
034c6ed7 LP |
913 | |
914 | m->dispatching_run_queue = false; | |
9152c765 LP |
915 | } |
916 | ||
034c6ed7 | 917 | static int manager_dispatch_sigchld(Manager *m) { |
9152c765 LP |
918 | assert(m); |
919 | ||
920 | for (;;) { | |
921 | siginfo_t si; | |
922 | Name *n; | |
923 | ||
924 | zero(si); | |
925 | if (waitid(P_ALL, 0, &si, WNOHANG) < 0) | |
926 | return -errno; | |
927 | ||
928 | if (si.si_pid == 0) | |
929 | break; | |
930 | ||
034c6ed7 LP |
931 | if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED) |
932 | continue; | |
933 | ||
9152c765 LP |
934 | if (!(n = hashmap_remove(m->watch_pids, UINT32_TO_PTR(si.si_pid)))) |
935 | continue; | |
936 | ||
937 | NAME_VTABLE(n)->sigchld_event(n, si.si_pid, si.si_code, si.si_status); | |
938 | } | |
939 | ||
940 | return 0; | |
941 | } | |
942 | ||
034c6ed7 | 943 | static int manager_process_signal_fd(Manager *m) { |
9152c765 LP |
944 | ssize_t n; |
945 | struct signalfd_siginfo sfsi; | |
946 | bool sigchld = false; | |
947 | ||
948 | assert(m); | |
949 | ||
950 | for (;;) { | |
951 | if ((n = read(m->signal_fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) { | |
952 | ||
953 | if (n >= 0) | |
954 | return -EIO; | |
955 | ||
956 | if (errno == EAGAIN) | |
957 | return 0; | |
958 | ||
959 | return -errno; | |
960 | } | |
961 | ||
962 | if (sfsi.ssi_signo == SIGCHLD) | |
963 | sigchld = true; | |
964 | } | |
965 | ||
966 | if (sigchld) | |
034c6ed7 LP |
967 | return manager_dispatch_sigchld(m); |
968 | ||
969 | return 0; | |
970 | } | |
971 | ||
972 | static int process_event(Manager *m, struct epoll_event *ev) { | |
973 | int r; | |
974 | ||
975 | assert(m); | |
976 | assert(ev); | |
977 | ||
978 | switch (ev->data.u32) { | |
979 | ||
980 | case MANAGER_SIGNAL: | |
981 | assert(ev->data.fd == m->signal_fd); | |
982 | ||
983 | /* An incoming signal? */ | |
984 | if (ev->events != POLLIN) | |
985 | return -EINVAL; | |
986 | ||
987 | if ((r = manager_process_signal_fd(m)) < 0) | |
988 | return -r; | |
989 | ||
990 | break; | |
991 | ||
992 | case MANAGER_FD: { | |
993 | Name *n; | |
994 | ||
995 | /* Some fd event, to be dispatched to the names */ | |
996 | assert_se(n = ev->data.ptr); | |
997 | NAME_VTABLE(n)->fd_event(n, ev->data.fd, ev->events); | |
998 | break; | |
999 | } | |
1000 | ||
1001 | case MANAGER_TIMER: { | |
1002 | Name *n; | |
1003 | uint64_t u; | |
1004 | ssize_t k; | |
1005 | ||
1006 | /* Some timer event, to be dispatched to the names */ | |
1007 | if ((k = read(ev->data.fd, &u, sizeof(u))) != sizeof(u)) { | |
1008 | ||
1009 | if (k < 0 && (errno == EINTR || errno == EAGAIN)) | |
1010 | break; | |
1011 | ||
1012 | return k < 0 ? -errno : -EIO; | |
1013 | } | |
1014 | ||
1015 | assert_se(n = ev->data.ptr); | |
1016 | NAME_VTABLE(n)->timer_event(n, ev->data.fd, u); | |
1017 | break; | |
1018 | } | |
1019 | ||
1020 | default: | |
1021 | assert_not_reached("Unknown epoll event type."); | |
1022 | } | |
9152c765 LP |
1023 | |
1024 | return 0; | |
1025 | } | |
1026 | ||
1027 | int manager_loop(Manager *m) { | |
1028 | int r; | |
9152c765 LP |
1029 | |
1030 | assert(m); | |
1031 | ||
1032 | for (;;) { | |
034c6ed7 | 1033 | struct epoll_event events[32]; |
9152c765 LP |
1034 | int n, i; |
1035 | ||
034c6ed7 LP |
1036 | manager_dispatch_run_queue(m); |
1037 | ||
9152c765 LP |
1038 | if ((n = epoll_wait(m->epoll_fd, events, ELEMENTSOF(events), -1)) < 0) { |
1039 | ||
1040 | if (errno == -EINTR) | |
1041 | continue; | |
1042 | ||
1043 | return -errno; | |
1044 | } | |
1045 | ||
034c6ed7 LP |
1046 | for (i = 0; i < n; i++) |
1047 | if ((r = process_event(m, events + i)) < 0) | |
1048 | return r; | |
83c60c9f LP |
1049 | } |
1050 | } |