1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
6 This file is part of systemd.
8 Copyright 2010 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
27 typedef struct Unit Unit;
28 typedef struct UnitVTable UnitVTable;
29 typedef enum UnitActiveState UnitActiveState;
30 typedef enum UnitDependency UnitDependency;
31 typedef struct UnitRef UnitRef;
32 typedef struct UnitStatusMessageFormats UnitStatusMessageFormats;
37 #include "socket-util.h"
39 #include "condition.h"
41 #include "unit-name.h"
43 enum UnitActiveState {
50 _UNIT_ACTIVE_STATE_MAX,
51 _UNIT_ACTIVE_STATE_INVALID = -1
54 static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
55 return t == UNIT_ACTIVE || t == UNIT_RELOADING;
58 static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
59 return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_RELOADING;
62 static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
63 return t == UNIT_INACTIVE || t == UNIT_FAILED || t == UNIT_DEACTIVATING;
66 static inline bool UNIT_IS_INACTIVE_OR_FAILED(UnitActiveState t) {
67 return t == UNIT_INACTIVE || t == UNIT_FAILED;
71 /* Positive dependencies */
73 UNIT_REQUIRES_OVERRIDABLE,
75 UNIT_REQUISITE_OVERRIDABLE,
80 /* Inverse of the above */
81 UNIT_REQUIRED_BY, /* inverse of 'requires' and 'requisite' is 'required_by' */
82 UNIT_REQUIRED_BY_OVERRIDABLE, /* inverse of 'requires_overridable' and 'requisite_overridable' is 'soft_required_by' */
83 UNIT_WANTED_BY, /* inverse of 'wants' */
84 UNIT_BOUND_BY, /* inverse of 'binds_to' */
85 UNIT_CONSISTS_OF, /* inverse of 'part_of' */
87 /* Negative dependencies */
88 UNIT_CONFLICTS, /* inverse of 'conflicts' is 'conflicted_by' */
92 UNIT_BEFORE, /* inverse of 'before' is 'after' and vice versa */
98 /* Triggers (i.e. a socket triggers a service) */
102 /* Propagate reloads */
103 UNIT_PROPAGATES_RELOAD_TO,
104 UNIT_RELOAD_PROPAGATED_FROM,
106 /* Reference information for GC logic */
107 UNIT_REFERENCES, /* Inverse of 'references' is 'referenced_by' */
110 _UNIT_DEPENDENCY_MAX,
111 _UNIT_DEPENDENCY_INVALID = -1
117 #include "cgroup-attr.h"
123 UnitLoadState load_state;
126 char *id; /* One name is special because we use it for identification. Points to an entry in the names set */
130 Set *dependencies[_UNIT_DEPENDENCY_MAX];
132 char **requires_mounts_for;
135 char **documentation;
137 char *fragment_path; /* if loaded from a config file this is the primary path to it */
138 char *source_path; /* if converted, the source file */
139 usec_t fragment_mtime;
142 /* If there is something to do with this unit, then this is the installed job for it */
145 /* JOB_NOP jobs are special and can be installed without disturbing the real job. */
150 /* References to this */
151 LIST_HEAD(UnitRef, refs);
153 /* Conditions to check */
154 LIST_HEAD(Condition, conditions);
156 dual_timestamp condition_timestamp;
158 dual_timestamp inactive_exit_timestamp;
159 dual_timestamp active_enter_timestamp;
160 dual_timestamp active_exit_timestamp;
161 dual_timestamp inactive_enter_timestamp;
163 /* Counterparts in the cgroup filesystem */
164 CGroupBonding *cgroup_bondings;
165 CGroupAttribute *cgroup_attributes;
168 LIST_FIELDS(Unit, units_by_type);
170 /* All units which have requires_mounts_for set */
171 LIST_FIELDS(Unit, has_requires_mounts_for);
174 LIST_FIELDS(Unit, load_queue);
177 LIST_FIELDS(Unit, dbus_queue);
180 LIST_FIELDS(Unit, cleanup_queue);
183 LIST_FIELDS(Unit, gc_queue);
185 /* Used during GC sweeps */
188 /* When deserializing, temporarily store the job type for this
189 * unit here, if there was a job scheduled.
190 * Only for deserializing from a legacy version. New style uses full
191 * serialized jobs. */
192 int deserialized_job; /* This is actually of type JobType */
194 /* Error code when we didn't manage to load the unit (negative) */
197 /* Cached unit file state */
198 UnitFileState unit_file_state;
200 /* Garbage collect us we nobody wants or requires us anymore */
201 bool stop_when_unneeded;
203 /* Create default dependencies */
204 bool default_dependencies;
206 /* Refuse manual starting, allow starting only indirectly via dependency. */
207 bool refuse_manual_start;
209 /* Don't allow the user to stop this unit manually, allow stopping only indirectly via dependency. */
210 bool refuse_manual_stop;
212 /* Allow isolation requests */
215 /* Isolate OnFailure unit */
216 bool on_failure_isolate;
218 /* Ignore this unit when isolating */
219 bool ignore_on_isolate;
221 /* Ignore this unit when snapshotting */
222 bool ignore_on_snapshot;
224 /* Did the last condition check succeed? */
225 bool condition_result;
227 bool in_load_queue:1;
228 bool in_dbus_queue:1;
229 bool in_cleanup_queue:1;
232 bool sent_dbus_new_signal:1;
240 /* Keeps tracks of references to a unit. This is useful so
241 * that we can merge two units if necessary and correct all
242 * references to them */
245 LIST_FIELDS(UnitRef, refs);
248 struct UnitStatusMessageFormats {
249 const char *starting_stopping[2];
250 const char *finished_start_job[_JOB_RESULT_MAX];
251 const char *finished_stop_job[_JOB_RESULT_MAX];
260 #include "automount.h"
261 #include "snapshot.h"
266 /* How much memory does an object of this unit type need */
269 /* If greater than 0, the offset into the object where
270 * ExecContext is found, if the unit type has that */
271 size_t exec_context_offset;
273 /* Config file sections this unit type understands, separated
275 const char *sections;
277 /* This should reset all type-specific variables. This should
278 * not allocate memory, and is called with zero-initialized
279 * data. It should hence only initialize variables that need
281 void (*init)(Unit *u);
283 /* This should free all type-specific variables. It should be
285 void (*done)(Unit *u);
287 /* Actually load data from disk. This may fail, and should set
288 * load_state to UNIT_LOADED, UNIT_MERGED or leave it at
289 * UNIT_STUB if no configuration could be found. */
290 int (*load)(Unit *u);
292 /* If a lot of units got created via enumerate(), this is
293 * where to actually set the state and call unit_notify(). */
294 int (*coldplug)(Unit *u);
296 void (*dump)(Unit *u, FILE *f, const char *prefix);
298 int (*start)(Unit *u);
299 int (*stop)(Unit *u);
300 int (*reload)(Unit *u);
302 int (*kill)(Unit *u, KillWho w, int signo, DBusError *error);
304 bool (*can_reload)(Unit *u);
306 /* Write all data that cannot be restored from other sources
307 * away using unit_serialize_item() */
308 int (*serialize)(Unit *u, FILE *f, FDSet *fds);
310 /* Restore one item from the serialization */
311 int (*deserialize_item)(Unit *u, const char *key, const char *data, FDSet *fds);
313 /* Boils down the more complex internal state of this unit to
314 * a simpler one that the engine can understand */
315 UnitActiveState (*active_state)(Unit *u);
317 /* Returns the substate specific to this unit type as
318 * string. This is purely information so that we can give the
319 * user a more fine grained explanation in which actual state a
321 const char* (*sub_state_to_string)(Unit *u);
323 /* Return true when there is reason to keep this entry around
324 * even nothing references it and it isn't active in any
326 bool (*check_gc)(Unit *u);
328 /* Return true when this unit is suitable for snapshotting */
329 bool (*check_snapshot)(Unit *u);
331 void (*fd_event)(Unit *u, int fd, uint32_t events, Watch *w);
332 void (*sigchld_event)(Unit *u, pid_t pid, int code, int status);
333 void (*timer_event)(Unit *u, uint64_t n_elapsed, Watch *w);
335 /* Reset failed state if we are in failed state */
336 void (*reset_failed)(Unit *u);
338 /* Called whenever any of the cgroups this unit watches for
340 void (*cgroup_notify_empty)(Unit *u);
342 /* Called whenever a process of this unit sends us a message */
343 void (*notify_message)(Unit *u, pid_t pid, char **tags);
345 /* Called whenever a name thus Unit registered for comes or
347 void (*bus_name_owner_change)(Unit *u, const char *name, const char *old_owner, const char *new_owner);
349 /* Called whenever a bus PID lookup finishes */
350 void (*bus_query_pid_done)(Unit *u, const char *name, pid_t pid);
352 /* Called for each message received on the bus */
353 DBusHandlerResult (*bus_message_handler)(Unit *u, DBusConnection *c, DBusMessage *message);
355 /* Return the unit this unit is following */
356 Unit *(*following)(Unit *u);
358 /* Return the set of units that are following each other */
359 int (*following_set)(Unit *u, Set **s);
361 /* Called whenever CLOCK_REALTIME made a jump */
362 void (*time_change)(Unit *u);
364 /* This is called for each unit type and should be used to
365 * enumerate existing devices and load them. However,
366 * everything that is loaded here should still stay in
367 * inactive state. It is the job of the coldplug() call above
368 * to put the units into the initial state. */
369 int (*enumerate)(Manager *m);
371 /* Type specific cleanups. */
372 void (*shutdown)(Manager *m);
374 /* When sending out PropertiesChanged signal, which properties
375 * shall be invalidated? This is a NUL separated list of
376 * strings, to minimize relocations a little. */
377 const char *bus_invalidating_properties;
379 /* The interface name */
380 const char *bus_interface;
382 UnitStatusMessageFormats status_message_formats;
384 /* Can units of this type have multiple names? */
387 /* Instances make no sense for this type */
390 /* Exclude from automatic gc */
394 extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX];
396 #define UNIT_VTABLE(u) unit_vtable[(u)->type]
398 /* For casting a unit into the various unit types */
399 #define DEFINE_CAST(UPPERCASE, MixedCase) \
400 static inline MixedCase* UPPERCASE(Unit *u) { \
401 if (_unlikely_(!u || u->type != UNIT_##UPPERCASE)) \
404 return (MixedCase*) u; \
407 /* For casting the various unit types into a unit */
408 #define UNIT(u) (&(u)->meta)
410 DEFINE_CAST(SOCKET, Socket);
411 DEFINE_CAST(TIMER, Timer);
412 DEFINE_CAST(SERVICE, Service);
413 DEFINE_CAST(TARGET, Target);
414 DEFINE_CAST(DEVICE, Device);
415 DEFINE_CAST(MOUNT, Mount);
416 DEFINE_CAST(AUTOMOUNT, Automount);
417 DEFINE_CAST(SNAPSHOT, Snapshot);
418 DEFINE_CAST(SWAP, Swap);
419 DEFINE_CAST(PATH, Path);
421 Unit *unit_new(Manager *m, size_t size);
422 void unit_free(Unit *u);
424 int unit_add_name(Unit *u, const char *name);
426 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference);
427 int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference);
429 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
430 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference);
432 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
433 int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference);
435 int unit_add_exec_dependencies(Unit *u, ExecContext *c);
437 int unit_add_cgroup(Unit *u, CGroupBonding *b);
438 int unit_add_cgroup_from_text(Unit *u, const char *name);
439 int unit_add_default_cgroups(Unit *u);
440 CGroupBonding* unit_get_default_cgroup(Unit *u);
441 int unit_add_cgroup_attribute(Unit *u, const char *controller, const char *name, const char *value, CGroupAttributeMapCallback map_callback);
443 int unit_choose_id(Unit *u, const char *name);
444 int unit_set_description(Unit *u, const char *description);
446 bool unit_check_gc(Unit *u);
448 void unit_add_to_load_queue(Unit *u);
449 void unit_add_to_dbus_queue(Unit *u);
450 void unit_add_to_cleanup_queue(Unit *u);
451 void unit_add_to_gc_queue(Unit *u);
453 int unit_merge(Unit *u, Unit *other);
454 int unit_merge_by_name(Unit *u, const char *other);
456 Unit *unit_follow_merge(Unit *u);
458 int unit_load_fragment_and_dropin(Unit *u);
459 int unit_load_fragment_and_dropin_optional(Unit *u);
460 int unit_load(Unit *unit);
462 const char *unit_description(Unit *u);
464 bool unit_has_name(Unit *u, const char *name);
466 UnitActiveState unit_active_state(Unit *u);
468 const char* unit_sub_state_to_string(Unit *u);
470 void unit_dump(Unit *u, FILE *f, const char *prefix);
472 bool unit_can_reload(Unit *u);
473 bool unit_can_start(Unit *u);
474 bool unit_can_isolate(Unit *u);
476 int unit_start(Unit *u);
477 int unit_stop(Unit *u);
478 int unit_reload(Unit *u);
480 int unit_kill(Unit *u, KillWho w, int signo, DBusError *error);
482 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_success);
484 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w);
485 void unit_unwatch_fd(Unit *u, Watch *w);
487 int unit_watch_pid(Unit *u, pid_t pid);
488 void unit_unwatch_pid(Unit *u, pid_t pid);
490 int unit_watch_timer(Unit *u, clockid_t, bool relative, usec_t usec, Watch *w);
491 void unit_unwatch_timer(Unit *u, Watch *w);
493 int unit_watch_bus_name(Unit *u, const char *name);
494 void unit_unwatch_bus_name(Unit *u, const char *name);
496 bool unit_job_is_applicable(Unit *u, JobType j);
498 int set_unit_path(const char *p);
500 char *unit_dbus_path(Unit *u);
502 int unit_load_related_unit(Unit *u, const char *type, Unit **_found);
503 int unit_get_related_unit(Unit *u, const char *type, Unit **_found);
505 bool unit_can_serialize(Unit *u);
506 int unit_serialize(Unit *u, FILE *f, FDSet *fds, bool serialize_jobs);
507 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *value, ...) _printf_attr_(4,5);
508 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value);
509 int unit_deserialize(Unit *u, FILE *f, FDSet *fds);
511 int unit_add_node_link(Unit *u, const char *what, bool wants);
513 int unit_coldplug(Unit *u);
515 void unit_status_printf(Unit *u, const char *status, const char *format, ...);
517 bool unit_need_daemon_reload(Unit *u);
519 void unit_reset_failed(Unit *u);
521 Unit *unit_following(Unit *u);
523 bool unit_pending_inactive(Unit *u);
524 bool unit_pending_active(Unit *u);
526 int unit_add_default_target_dependency(Unit *u, Unit *target);
528 char *unit_default_cgroup_path(Unit *u);
530 int unit_following_set(Unit *u, Set **s);
532 void unit_trigger_on_failure(Unit *u);
534 bool unit_condition_test(Unit *u);
536 UnitFileState unit_get_unit_file_state(Unit *u);
538 Unit* unit_ref_set(UnitRef *ref, Unit *u);
539 void unit_ref_unset(UnitRef *ref);
541 #define UNIT_DEREF(ref) ((ref).unit)
543 int unit_add_one_mount_link(Unit *u, Mount *m);
544 int unit_add_mount_links(Unit *u);
546 int unit_exec_context_defaults(Unit *u, ExecContext *c);
548 ExecContext *unit_get_exec_context(Unit *u);
550 const char *unit_active_state_to_string(UnitActiveState i);
551 UnitActiveState unit_active_state_from_string(const char *s);
553 const char *unit_dependency_to_string(UnitDependency i);
554 UnitDependency unit_dependency_from_string(const char *s);