unit.c 31.8 KB
Newer Older
Lennart Poettering's avatar
Lennart Poettering committed
1
2
/*-*- Mode: C; c-basic-offset: 8 -*-*/

3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
/***
  This file is part of systemd.

  Copyright 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

Lennart Poettering's avatar
Lennart Poettering committed
22
23
24
25
26
27
#include <assert.h>
#include <errno.h>
#include <string.h>
#include <sys/epoll.h>
#include <sys/timerfd.h>
#include <sys/poll.h>
28
29
#include <stdlib.h>
#include <unistd.h>
Lennart Poettering's avatar
Lennart Poettering committed
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65

#include "set.h"
#include "unit.h"
#include "macro.h"
#include "strv.h"
#include "load-fragment.h"
#include "load-dropin.h"
#include "log.h"

const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
        [UNIT_SERVICE] = &service_vtable,
        [UNIT_TIMER] = &timer_vtable,
        [UNIT_SOCKET] = &socket_vtable,
        [UNIT_TARGET] = &target_vtable,
        [UNIT_DEVICE] = &device_vtable,
        [UNIT_MOUNT] = &mount_vtable,
        [UNIT_AUTOMOUNT] = &automount_vtable,
        [UNIT_SNAPSHOT] = &snapshot_vtable
};

UnitType unit_name_to_type(const char *n) {
        UnitType t;

        assert(n);

        for (t = 0; t < _UNIT_TYPE_MAX; t++)
                if (endswith(n, unit_vtable[t]->suffix))
                        return t;

        return _UNIT_TYPE_INVALID;
}

#define VALID_CHARS                             \
        "0123456789"                            \
        "abcdefghijklmnopqrstuvwxyz"            \
        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"            \
66
        "-_.\\"
Lennart Poettering's avatar
Lennart Poettering committed
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83

bool unit_name_is_valid(const char *n) {
        UnitType t;
        const char *e, *i;

        assert(n);

        if (strlen(n) >= UNIT_NAME_MAX)
                return false;

        t = unit_name_to_type(n);
        if (t < 0 || t >= _UNIT_TYPE_MAX)
                return false;

        if (!(e = strrchr(n, '.')))
                return false;

84
85
86
        if (e == n)
                return false;

Lennart Poettering's avatar
Lennart Poettering committed
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
        for (i = n; i < e; i++)
                if (!strchr(VALID_CHARS, *i))
                        return false;

        return true;
}

char *unit_name_change_suffix(const char *n, const char *suffix) {
        char *e, *r;
        size_t a, b;

        assert(n);
        assert(unit_name_is_valid(n));
        assert(suffix);

        assert_se(e = strrchr(n, '.'));
        a = e - n;
        b = strlen(suffix);

        if (!(r = new(char, a + b + 1)))
                return NULL;

        memcpy(r, n, a);
        memcpy(r+a, suffix, b+1);

        return r;
}

Unit *unit_new(Manager *m) {
        Unit *u;

        assert(m);

        if (!(u = new0(Unit, 1)))
                return NULL;

        if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
                free(u);
                return NULL;
        }

        u->meta.manager = m;
        u->meta.type = _UNIT_TYPE_INVALID;

        return u;
}

int unit_add_name(Unit *u, const char *text) {
        UnitType t;
        char *s;
        int r;

        assert(u);
        assert(text);

        if (!unit_name_is_valid(text))
                return -EINVAL;

        if ((t = unit_name_to_type(text)) == _UNIT_TYPE_INVALID)
                return -EINVAL;

        if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type)
                return -EINVAL;

        if (!(s = strdup(text)))
                return -ENOMEM;

        if ((r = set_put(u->meta.names, s)) < 0) {
                free(s);

                if (r == -EEXIST)
                        return 0;

                return r;
        }

        if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
                set_remove(u->meta.names, s);
                free(s);
                return r;
        }

Lennart Poettering's avatar
Lennart Poettering committed
169
170
171
        if (u->meta.type == _UNIT_TYPE_INVALID)
                LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);

Lennart Poettering's avatar
Lennart Poettering committed
172
173
174
175
176
        u->meta.type = t;

        if (!u->meta.id)
                u->meta.id = s;

177
        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
178
179
180
        return 0;
}

181
182
183
184
185
186
187
188
189
190
191
192
int unit_choose_id(Unit *u, const char *name) {
        char *s;

        assert(u);
        assert(name);

        /* Selects one of the names of this unit as the id */

        if (!(s = set_get(u->meta.names, (char*) name)))
                return -ENOENT;

        u->meta.id = s;
193
194

        unit_add_to_dbus_queue(u);
195
196
197
        return 0;
}

Lennart Poettering's avatar
Lennart Poettering committed
198
199
200
201
202
203
204
205
206
207
int unit_set_description(Unit *u, const char *description) {
        char *s;

        assert(u);

        if (!(s = strdup(description)))
                return -ENOMEM;

        free(u->meta.description);
        u->meta.description = s;
208
209

        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
210
211
212
        return 0;
}

Lennart Poettering's avatar
Lennart Poettering committed
213
214
215
216
217
218
219
220
221
222
void unit_add_to_load_queue(Unit *u) {
        assert(u);

        if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
                return;

        LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
        u->meta.in_load_queue = true;
}

223
224
225
226
227
228
229
230
231
232
void unit_add_to_dbus_queue(Unit *u) {
        assert(u);

        if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue || set_isempty(u->meta.manager->subscribed))
                return;

        LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
        u->meta.in_dbus_queue = true;
}

Lennart Poettering's avatar
Lennart Poettering committed
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
static void bidi_set_free(Unit *u, Set *s) {
        Iterator i;
        Unit *other;

        assert(u);

        /* Frees the set and makes sure we are dropped from the
         * inverse pointers */

        SET_FOREACH(other, s, i) {
                UnitDependency d;

                for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
                        set_remove(other->meta.dependencies[d], u);
        }

        set_free(s);
}

void unit_free(Unit *u) {
        UnitDependency d;
        Iterator i;
        char *t;

        assert(u);

259
260
        bus_unit_send_removed_signal(u);

Lennart Poettering's avatar
Lennart Poettering committed
261
262
263
264
265
        /* Detach from next 'bigger' objects */

        SET_FOREACH(t, u->meta.names, i)
                hashmap_remove_value(u->meta.manager->units, t, u);

Lennart Poettering's avatar
Lennart Poettering committed
266
267
268
        if (u->meta.type != _UNIT_TYPE_INVALID)
                LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);

Lennart Poettering's avatar
Lennart Poettering committed
269
270
271
        if (u->meta.in_load_queue)
                LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);

272
273
274
        if (u->meta.in_dbus_queue)
                LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);

Lennart Poettering's avatar
Lennart Poettering committed
275
276
277
278
279
280
281
282
283
284
285
286
        if (u->meta.load_state == UNIT_LOADED)
                if (UNIT_VTABLE(u)->done)
                        UNIT_VTABLE(u)->done(u);

        /* Free data and next 'smaller' objects */
        if (u->meta.job)
                job_free(u->meta.job);

        for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
                bidi_set_free(u, u->meta.dependencies[d]);

        free(u->meta.description);
287
        free(u->meta.fragment_path);
Lennart Poettering's avatar
Lennart Poettering committed
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318

        while ((t = set_steal_first(u->meta.names)))
                free(t);
        set_free(u->meta.names);

        free(u);
}

UnitActiveState unit_active_state(Unit *u) {
        assert(u);

        if (u->meta.load_state != UNIT_LOADED)
                return UNIT_INACTIVE;

        return UNIT_VTABLE(u)->active_state(u);
}

static int ensure_merge(Set **s, Set *other) {

        if (!other)
                return 0;

        if (*s)
                return set_merge(*s, other);

        if (!(*s = set_copy(other)))
                return -ENOMEM;

        return 0;
}

319
320
/* FIXME: Does not rollback on failure! Needs to fix special unit
 * pointers. Needs to merge names and dependencies properly.*/
Lennart Poettering's avatar
Lennart Poettering committed
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
int unit_merge(Unit *u, Unit *other) {
        int r;
        UnitDependency d;

        assert(u);
        assert(other);
        assert(u->meta.manager == other->meta.manager);

        /* This merges 'other' into 'unit'. FIXME: This does not
         * rollback on failure. */

        if (u->meta.type != u->meta.type)
                return -EINVAL;

        if (u->meta.load_state != UNIT_STUB)
                return -EINVAL;

        /* Merge names */
        if ((r = ensure_merge(&u->meta.names, other->meta.names)) < 0)
                return r;

        /* Merge dependencies */
        for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
                /* fixme, the inverse mapping is missing */
                if ((r = ensure_merge(&u->meta.dependencies[d], other->meta.dependencies[d])) < 0)
                        return r;

348
349
        unit_add_to_dbus_queue(u);

Lennart Poettering's avatar
Lennart Poettering committed
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
        return 0;
}

const char* unit_id(Unit *u) {
        assert(u);

        if (u->meta.id)
                return u->meta.id;

        return set_first(u->meta.names);
}

const char *unit_description(Unit *u) {
        assert(u);

        if (u->meta.description)
                return u->meta.description;

        return unit_id(u);
}

void unit_dump(Unit *u, FILE *f, const char *prefix) {

        char *t;
        UnitDependency d;
        Iterator i;
376
377
        char *p2;
        const char *prefix2;
Lennart Poettering's avatar
Lennart Poettering committed
378
379
380
381
382

        assert(u);

        if (!prefix)
                prefix = "";
383
384
        p2 = strappend(prefix, "\t");
        prefix2 = p2 ? p2 : prefix;
Lennart Poettering's avatar
Lennart Poettering committed
385
386
387
388
389

        fprintf(f,
                "%s→ Unit %s:\n"
                "%s\tDescription: %s\n"
                "%s\tUnit Load State: %s\n"
390
                "%s\tUnit Active State: %s\n"
391
                "%s\tRecursive Stop: %s\n"
392
                "%s\tStop When Unneeded: %s\n",
Lennart Poettering's avatar
Lennart Poettering committed
393
394
                prefix, unit_id(u),
                prefix, unit_description(u),
395
396
                prefix, unit_load_state_to_string(u->meta.load_state),
                prefix, unit_active_state_to_string(unit_active_state(u)),
397
398
                prefix, yes_no(u->meta.recursive_stop),
                prefix, yes_no(u->meta.stop_when_unneeded));
Lennart Poettering's avatar
Lennart Poettering committed
399

400
401
        if (u->meta.fragment_path)
                fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
402

Lennart Poettering's avatar
Lennart Poettering committed
403
404
405
406
407
408
409
410
411
412
        SET_FOREACH(t, u->meta.names, i)
                fprintf(f, "%s\tName: %s\n", prefix, t);

        for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
                Unit *other;

                if (set_isempty(u->meta.dependencies[d]))
                        continue;

                SET_FOREACH(other, u->meta.dependencies[d], i)
413
                        fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), unit_id(other));
Lennart Poettering's avatar
Lennart Poettering committed
414
415
416
417
418
419
420
421
        }

        if (UNIT_VTABLE(u)->dump)
                UNIT_VTABLE(u)->dump(u, f, prefix2);

        if (u->meta.job)
                job_dump(u->meta.job, f, prefix2);

422
        free(p2);
Lennart Poettering's avatar
Lennart Poettering committed
423
424
425
426
}

/* Common implementation for multiple backends */
int unit_load_fragment_and_dropin(Unit *u) {
427
        int r, ret;
Lennart Poettering's avatar
Lennart Poettering committed
428
429
430
431
432
433
434

        assert(u);

        /* Load a .socket file */
        if ((r = unit_load_fragment(u)) < 0)
                return r;

435
436
        ret = r > 0;

Lennart Poettering's avatar
Lennart Poettering committed
437
438
439
440
        /* Load drop-in directory data */
        if ((r = unit_load_dropin(u)) < 0)
                return r;

441
        return ret;
Lennart Poettering's avatar
Lennart Poettering committed
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
}

int unit_load(Unit *u) {
        int r;

        assert(u);

        if (u->meta.in_load_queue) {
                LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
                u->meta.in_load_queue = false;
        }

        if (u->meta.load_state != UNIT_STUB)
                return 0;

        if (UNIT_VTABLE(u)->init)
                if ((r = UNIT_VTABLE(u)->init(u)) < 0)
                        goto fail;

        u->meta.load_state = UNIT_LOADED;
462
        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
463
464
465
466
        return 0;

fail:
        u->meta.load_state = UNIT_FAILED;
467
        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
468
469
470
471
472
473
474
475
476
477
478
479
480
        return r;
}

/* Errors:
 *         -EBADR:    This unit type does not support starting.
 *         -EALREADY: Unit is already started.
 *         -EAGAIN:   An operation is already in progress. Retry later.
 */
int unit_start(Unit *u) {
        UnitActiveState state;

        assert(u);

481
482
483
484
        /* If this is already (being) started, then this will
         * succeed. Note that this will even succeed if this unit is
         * not startable by the user. This is relied on to detect when
         * we need to wait for units and when waiting is finished. */
Lennart Poettering's avatar
Lennart Poettering committed
485
486
487
488
        state = unit_active_state(u);
        if (UNIT_IS_ACTIVE_OR_RELOADING(state))
                return -EALREADY;

489
490
491
492
        /* If it is stopped, but we cannot start it, then fail */
        if (!UNIT_VTABLE(u)->start)
                return -EBADR;

Lennart Poettering's avatar
Lennart Poettering committed
493
494
495
496
497
498
        /* We don't suppress calls to ->start() here when we are
         * already starting, to allow this request to be used as a
         * "hurry up" call, for example when the unit is in some "auto
         * restart" state where it waits for a holdoff timer to elapse
         * before it will start again. */

499
        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
        return UNIT_VTABLE(u)->start(u);
}

bool unit_can_start(Unit *u) {
        assert(u);

        return !!UNIT_VTABLE(u)->start;
}

/* Errors:
 *         -EBADR:    This unit type does not support stopping.
 *         -EALREADY: Unit is already stopped.
 *         -EAGAIN:   An operation is already in progress. Retry later.
 */
int unit_stop(Unit *u) {
        UnitActiveState state;

        assert(u);

        state = unit_active_state(u);
        if (state == UNIT_INACTIVE)
                return -EALREADY;

523
524
525
        if (!UNIT_VTABLE(u)->stop)
                return -EBADR;

Lennart Poettering's avatar
Lennart Poettering committed
526
527
528
        if (state == UNIT_DEACTIVATING)
                return 0;

529
        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
        return UNIT_VTABLE(u)->stop(u);
}

/* Errors:
 *         -EBADR:    This unit type does not support reloading.
 *         -ENOEXEC:  Unit is not started.
 *         -EAGAIN:   An operation is already in progress. Retry later.
 */
int unit_reload(Unit *u) {
        UnitActiveState state;

        assert(u);

        if (!unit_can_reload(u))
                return -EBADR;

        state = unit_active_state(u);
        if (unit_active_state(u) == UNIT_ACTIVE_RELOADING)
                return -EALREADY;

        if (unit_active_state(u) != UNIT_ACTIVE)
                return -ENOEXEC;

553
        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
        return UNIT_VTABLE(u)->reload(u);
}

bool unit_can_reload(Unit *u) {
        assert(u);

        if (!UNIT_VTABLE(u)->reload)
                return false;

        if (!UNIT_VTABLE(u)->can_reload)
                return true;

        return UNIT_VTABLE(u)->can_reload(u);
}

569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
static void unit_check_uneeded(Unit *u) {
        Iterator i;
        Unit *other;

        assert(u);

        /* If this service shall be shut down when unneeded then do
         * so. */

        if (!u->meta.stop_when_unneeded)
                return;

        if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
                return;

        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                        return;

        SET_FOREACH(other, u->meta.dependencies[UNIT_SOFT_REQUIRED_BY], i)
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                        return;

        SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                        return;

        log_debug("Service %s is not needed anymore. Stopping.", unit_id(u));

        /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
        manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL);
}

Lennart Poettering's avatar
Lennart Poettering committed
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
static void retroactively_start_dependencies(Unit *u) {
        Iterator i;
        Unit *other;

        assert(u);
        assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));

        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
                        manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);

        SET_FOREACH(other, u->meta.dependencies[UNIT_SOFT_REQUIRES], i)
                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
                        manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);

        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
                        manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);

        SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
                        manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);

        SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
                        manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
}

static void retroactively_stop_dependencies(Unit *u) {
        Iterator i;
        Unit *other;

        assert(u);
        assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));

637
638
639
640
641
642
643
644
645
        if (u->meta.recursive_stop) {
                /* Pull down units need us recursively if enabled */
                SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
                        if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                                manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
        }

        /* Garbage collect services that might not be needed anymore, if enabled */
        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
Lennart Poettering's avatar
Lennart Poettering committed
646
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
647
648
649
650
651
652
653
654
655
656
657
658
659
                        unit_check_uneeded(other);
        SET_FOREACH(other, u->meta.dependencies[UNIT_SOFT_REQUIRES], i)
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                        unit_check_uneeded(other);
        SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                        unit_check_uneeded(other);
        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                        unit_check_uneeded(other);
        SET_FOREACH(other, u->meta.dependencies[UNIT_SOFT_REQUISITE], i)
                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
                        unit_check_uneeded(other);
Lennart Poettering's avatar
Lennart Poettering committed
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
}

void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns) {
        assert(u);
        assert(os < _UNIT_ACTIVE_STATE_MAX);
        assert(ns < _UNIT_ACTIVE_STATE_MAX);
        assert(!(os == UNIT_ACTIVE && ns == UNIT_ACTIVATING));
        assert(!(os == UNIT_INACTIVE && ns == UNIT_DEACTIVATING));

        if (os == ns)
                return;

        if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
                u->meta.active_enter_timestamp = now(CLOCK_REALTIME);
        else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
                u->meta.active_exit_timestamp = now(CLOCK_REALTIME);

        if (u->meta.job) {

                if (u->meta.job->state == JOB_WAITING)

                        /* So we reached a different state for this
                         * job. Let's see if we can run it now if it
                         * failed previously due to EAGAIN. */
684
                        job_add_to_run_queue(u->meta.job);
Lennart Poettering's avatar
Lennart Poettering committed
685
686
687
688

                else {
                        assert(u->meta.job->state == JOB_RUNNING);

Lennart Poettering's avatar
Lennart Poettering committed
689
                        /* Let's check whether this state change
Lennart Poettering's avatar
Lennart Poettering committed
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
                         * constitutes a finished job, or maybe
                         * cotradicts a running job and hence needs to
                         * invalidate jobs. */

                        switch (u->meta.job->type) {

                        case JOB_START:
                        case JOB_VERIFY_ACTIVE:

                                if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
                                        job_finish_and_invalidate(u->meta.job, true);
                                        return;
                                } else if (ns == UNIT_ACTIVATING)
                                        return;
                                else
                                        job_finish_and_invalidate(u->meta.job, false);

                                break;

                        case JOB_RELOAD:
                        case JOB_RELOAD_OR_START:

                                if (ns == UNIT_ACTIVE) {
                                        job_finish_and_invalidate(u->meta.job, true);
                                        return;
                                } else if (ns == UNIT_ACTIVATING || ns == UNIT_ACTIVE_RELOADING)
                                        return;
                                else
                                        job_finish_and_invalidate(u->meta.job, false);

                                break;

                        case JOB_STOP:
                        case JOB_RESTART:
                        case JOB_TRY_RESTART:

                                if (ns == UNIT_INACTIVE) {
                                        job_finish_and_invalidate(u->meta.job, true);
                                        return;
                                } else if (ns == UNIT_DEACTIVATING)
                                        return;
                                else
                                        job_finish_and_invalidate(u->meta.job, false);

                                break;

                        default:
                                assert_not_reached("Job type unknown");
                        }
                }
        }

        /* If this state change happened without being requested by a
         * job, then let's retroactively start or stop dependencies */

        if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
                retroactively_start_dependencies(u);
        else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
                retroactively_stop_dependencies(u);
749
750
751
752

        /* Maybe we finished startup and are now ready for being
         * stopped because unneeded? */
        unit_check_uneeded(u);
753
754

        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
755
756
}

757
int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
Lennart Poettering's avatar
Lennart Poettering committed
758
759
760
761
        struct epoll_event ev;

        assert(u);
        assert(fd >= 0);
762
        assert(w);
763
        assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
Lennart Poettering's avatar
Lennart Poettering committed
764
765

        zero(ev);
766
        ev.data.ptr = w;
Lennart Poettering's avatar
Lennart Poettering committed
767
768
        ev.events = events;

769
770
771
772
773
        if (epoll_ctl(u->meta.manager->epoll_fd,
                      w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
                      fd,
                      &ev) < 0)
                return -errno;
Lennart Poettering's avatar
Lennart Poettering committed
774

775
776
        w->fd = fd;
        w->type = WATCH_FD;
777
        w->data.unit = u;
Lennart Poettering's avatar
Lennart Poettering committed
778

779
        return 0;
Lennart Poettering's avatar
Lennart Poettering committed
780
781
}

782
void unit_unwatch_fd(Unit *u, Watch *w) {
Lennart Poettering's avatar
Lennart Poettering committed
783
        assert(u);
784
        assert(w);
Lennart Poettering's avatar
Lennart Poettering committed
785

786
787
788
        if (w->type == WATCH_INVALID)
                return;

789
790
        assert(w->type == WATCH_FD);
        assert(w->data.unit == u);
791
792
793
794
        assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);

        w->fd = -1;
        w->type = WATCH_INVALID;
795
        w->data.unit = NULL;
Lennart Poettering's avatar
Lennart Poettering committed
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
}

int unit_watch_pid(Unit *u, pid_t pid) {
        assert(u);
        assert(pid >= 1);

        return hashmap_put(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
}

void unit_unwatch_pid(Unit *u, pid_t pid) {
        assert(u);
        assert(pid >= 1);

        hashmap_remove(u->meta.manager->watch_pids, UINT32_TO_PTR(pid));
}

812
int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
Lennart Poettering's avatar
Lennart Poettering committed
813
        struct itimerspec its;
814
        int flags, fd;
Lennart Poettering's avatar
Lennart Poettering committed
815
816
817
        bool ours;

        assert(u);
818
        assert(w);
819
        assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
Lennart Poettering's avatar
Lennart Poettering committed
820
821
822

        /* This will try to reuse the old timer if there is one */

823
        if (w->type == WATCH_TIMER) {
Lennart Poettering's avatar
Lennart Poettering committed
824
                ours = false;
825
                fd = w->fd;
Lennart Poettering's avatar
Lennart Poettering committed
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
        } else {
                ours = true;
                if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
                        return -errno;
        }

        zero(its);

        if (delay <= 0) {
                /* Set absolute time in the past, but not 0, since we
                 * don't want to disarm the timer */
                its.it_value.tv_sec = 0;
                its.it_value.tv_nsec = 1;

                flags = TFD_TIMER_ABSTIME;
        } else {
                timespec_store(&its.it_value, delay);
                flags = 0;
        }

        /* This will also flush the elapse counter */
        if (timerfd_settime(fd, flags, &its, NULL) < 0)
                goto fail;

850
851
        if (w->type == WATCH_INVALID) {
                struct epoll_event ev;
Lennart Poettering's avatar
Lennart Poettering committed
852

853
854
                zero(ev);
                ev.data.ptr = w;
855
                ev.events = EPOLLIN;
856
857
858
859
860
861
862

                if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
                        goto fail;
        }

        w->fd = fd;
        w->type = WATCH_TIMER;
863
        w->data.unit = u;
Lennart Poettering's avatar
Lennart Poettering committed
864
865
866
867
868

        return 0;

fail:
        if (ours)
869
                close_nointr_nofail(fd);
Lennart Poettering's avatar
Lennart Poettering committed
870
871
872
873

        return -errno;
}

874
void unit_unwatch_timer(Unit *u, Watch *w) {
Lennart Poettering's avatar
Lennart Poettering committed
875
        assert(u);
876
        assert(w);
Lennart Poettering's avatar
Lennart Poettering committed
877

878
        if (w->type == WATCH_INVALID)
Lennart Poettering's avatar
Lennart Poettering committed
879
880
                return;

881
        assert(w->type == WATCH_TIMER && w->data.unit == u);
882
883
884
885
886
887

        assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
        assert_se(close_nointr(w->fd) == 0);

        w->fd = -1;
        w->type = WATCH_INVALID;
888
        w->data.unit = NULL;
Lennart Poettering's avatar
Lennart Poettering committed
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
}

bool unit_job_is_applicable(Unit *u, JobType j) {
        assert(u);
        assert(j >= 0 && j < _JOB_TYPE_MAX);

        switch (j) {

        case JOB_VERIFY_ACTIVE:
        case JOB_START:
                return true;

        case JOB_STOP:
        case JOB_RESTART:
        case JOB_TRY_RESTART:
                return unit_can_start(u);

        case JOB_RELOAD:
                return unit_can_reload(u);

        case JOB_RELOAD_OR_START:
                return unit_can_reload(u) && unit_can_start(u);

        default:
                assert_not_reached("Invalid job type");
        }
}

int unit_add_dependency(Unit *u, UnitDependency d, Unit *other) {

        static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
                [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
                [UNIT_SOFT_REQUIRES] = UNIT_SOFT_REQUIRED_BY,
                [UNIT_WANTS] = UNIT_WANTED_BY,
                [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
                [UNIT_SOFT_REQUISITE] = UNIT_SOFT_REQUIRED_BY,
                [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
                [UNIT_SOFT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
                [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
                [UNIT_CONFLICTS] = UNIT_CONFLICTS,
                [UNIT_BEFORE] = UNIT_AFTER,
                [UNIT_AFTER] = UNIT_BEFORE
        };
        int r;

        assert(u);
        assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
        assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
        assert(other);

        /* We won't allow dependencies on ourselves. We will not
         * consider them an error however. */
        if (u == other)
                return 0;

        if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0)
                return r;

        if ((r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
                return r;

        if ((r = set_put(u->meta.dependencies[d], other)) < 0)
                return r;

        if ((r = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
                set_remove(u->meta.dependencies[d], other);
                return r;
        }

958
        unit_add_to_dbus_queue(u);
Lennart Poettering's avatar
Lennart Poettering committed
959
960
        return 0;
}
961

962
963
964
965
966
967
968
969
970
971
972
973
974
int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name) {
        Unit *other;
        int r;

        if ((r = manager_load_unit(u->meta.manager, name, &other)) < 0)
                return r;

        if ((r = unit_add_dependency(u, d, other)) < 0)
                return r;

        return 0;
}

975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
int set_unit_path(const char *p) {
        char *cwd, *c;
        int r;

        /* This is mostly for debug purposes */

        if (path_is_absolute(p)) {
                if (!(c = strdup(p)))
                        return -ENOMEM;
        } else {
                if (!(cwd = get_current_dir_name()))
                        return -errno;

                r = asprintf(&c, "%s/%s", cwd, p);
                free(cwd);

                if (r < 0)
                        return -ENOMEM;
        }

995
        if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
996
997
998
999
1000
                r = -errno;
                free(c);
                return r;
        }