1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
7 This file is part of systemd.
9 Copyright 2010 Lennart Poettering
11 systemd is free software; you can redistribute it and/or modify it
12 under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 2 of the License, or
14 (at your option) any later version.
16 systemd is distributed in the hope that it will be useful, but
17 WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with systemd; If not, see <http://www.gnu.org/licenses/>.
28 typedef union Unit Unit;
29 typedef struct Meta Meta;
30 typedef struct UnitVTable UnitVTable;
31 typedef enum UnitType UnitType;
32 typedef enum UnitLoadState UnitLoadState;
33 typedef enum UnitActiveState UnitActiveState;
34 typedef enum UnitDependency UnitDependency;
39 #include "socket-util.h"
42 #define UNIT_NAME_MAX 128
43 #define DEFAULT_TIMEOUT_USEC (60*USEC_PER_SEC)
44 #define DEFAULT_RESTART_USEC (100*USEC_PER_MSEC)
46 typedef enum KillMode {
47 KILL_CONTROL_GROUP = 0,
52 _KILL_MODE_INVALID = -1
67 _UNIT_TYPE_INVALID = -1
76 _UNIT_LOAD_STATE_INVALID = -1
79 enum UnitActiveState {
86 _UNIT_ACTIVE_STATE_MAX,
87 _UNIT_ACTIVE_STATE_INVALID = -1
90 static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
91 return t == UNIT_ACTIVE || t == UNIT_RELOADING;
94 static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
95 return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_RELOADING;
98 static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
99 return t == UNIT_INACTIVE || t == UNIT_MAINTENANCE || t == UNIT_DEACTIVATING;
102 static inline bool UNIT_IS_INACTIVE_OR_MAINTENANCE(UnitActiveState t) {
103 return t == UNIT_INACTIVE || t == UNIT_MAINTENANCE;
106 enum UnitDependency {
107 /* Positive dependencies */
109 UNIT_REQUIRES_OVERRIDABLE,
111 UNIT_REQUISITE_OVERRIDABLE,
114 /* Inverse of the above */
115 UNIT_REQUIRED_BY, /* inverse of 'requires' and 'requisite' is 'required_by' */
116 UNIT_REQUIRED_BY_OVERRIDABLE, /* inverse of 'soft_requires' and 'soft_requisite' is 'soft_required_by' */
117 UNIT_WANTED_BY, /* inverse of 'wants' */
119 /* Negative dependencies */
120 UNIT_CONFLICTS, /* inverse of 'conflicts' is 'conflicts' */
123 UNIT_BEFORE, /* inverse of 'before' is 'after' and vice versa */
126 /* Reference information for GC logic */
127 UNIT_REFERENCES, /* Inverse of 'references' is 'referenced_by' */
130 _UNIT_DEPENDENCY_MAX,
131 _UNIT_DEPENDENCY_INVALID = -1
142 UnitLoadState load_state;
145 /* Refuse manual starting, allow starting only indirectly via dependency. */
146 bool only_by_dependency;
148 char *id; /* One name is special because we use it for identification. Points to an entry in the names set */
152 Set *dependencies[_UNIT_DEPENDENCY_MAX];
155 char *fragment_path; /* if loaded from a config file this is the primary path to it */
157 /* If there is something to do with this unit, then this is
161 dual_timestamp inactive_exit_timestamp;
162 dual_timestamp active_enter_timestamp;
163 dual_timestamp active_exit_timestamp;
164 dual_timestamp inactive_enter_timestamp;
166 /* Counterparts in the cgroup filesystem */
167 CGroupBonding *cgroup_bondings;
170 LIST_FIELDS(Meta, units_per_type);
173 LIST_FIELDS(Meta, load_queue);
176 LIST_FIELDS(Meta, dbus_queue);
179 LIST_FIELDS(Meta, cleanup_queue);
182 LIST_FIELDS(Meta, gc_queue);
184 /* Used during GC sweeps */
187 /* If we go down, pull down everything that depends on us, too */
190 /* Garbage collect us we nobody wants or requires us anymore */
191 bool stop_when_unneeded;
193 /* When deserializing, temporarily store the job type for this
194 * unit here, if there was a job scheduled */
195 int deserialized_job; /* This is actually of type JobType */
197 bool in_load_queue:1;
198 bool in_dbus_queue:1;
199 bool in_cleanup_queue:1;
202 bool sent_dbus_new_signal:1;
211 #include "automount.h"
212 #include "snapshot.h"
233 /* This should reset all type-specific variables. This should
234 * not allocate memory, and is called with zero-initialized
235 * data. It should hence only initialize variables that need
237 void (*init)(Unit *u);
239 /* This should free all type-specific variables. It should be
241 void (*done)(Unit *u);
243 /* Actually load data from disk. This may fail, and should set
244 * load_state to UNIT_LOADED, UNIT_MERGED or leave it at
245 * UNIT_STUB if no configuration could be found. */
246 int (*load)(Unit *u);
248 /* If a a lot of units got created via enumerate(), this is
249 * where to actually set the state and call unit_notify(). */
250 int (*coldplug)(Unit *u);
252 void (*dump)(Unit *u, FILE *f, const char *prefix);
254 int (*start)(Unit *u);
255 int (*stop)(Unit *u);
256 int (*reload)(Unit *u);
258 bool (*can_reload)(Unit *u);
260 /* Write all data that cannot be restored from other sources
261 * away using unit_serialize_item() */
262 int (*serialize)(Unit *u, FILE *f, FDSet *fds);
264 /* Restore one item from the serialization */
265 int (*deserialize_item)(Unit *u, const char *key, const char *data, FDSet *fds);
267 /* Boils down the more complex internal state of this unit to
268 * a simpler one that the engine can understand */
269 UnitActiveState (*active_state)(Unit *u);
271 /* Returns the substate specific to this unit type as
272 * string. This is purely information so that we can give the
273 * user a more finegrained explanation in which actual state a
275 const char* (*sub_state_to_string)(Unit *u);
277 /* Return true when there is reason to keep this entry around
278 * even nothing references it and it isn't active in any
280 bool (*check_gc)(Unit *u);
282 /* Return true when this unit is suitable for snapshotting */
283 bool (*check_snapshot)(Unit *u);
285 void (*fd_event)(Unit *u, int fd, uint32_t events, Watch *w);
286 void (*sigchld_event)(Unit *u, pid_t pid, int code, int status);
287 void (*timer_event)(Unit *u, uint64_t n_elapsed, Watch *w);
289 /* Called whenever any of the cgroups this unit watches for
291 void (*cgroup_notify_empty)(Unit *u);
293 /* Called whenever a process of this unit sends us a message */
294 void (*notify_message)(Unit *u, pid_t pid, char **tags);
296 /* Called whenever a name thus Unit registered for comes or
298 void (*bus_name_owner_change)(Unit *u, const char *name, const char *old_owner, const char *new_owner);
300 /* Called whenever a bus PID lookup finishes */
301 void (*bus_query_pid_done)(Unit *u, const char *name, pid_t pid);
303 /* Called for each message received on the bus */
304 DBusHandlerResult (*bus_message_handler)(Unit *u, DBusConnection *c, DBusMessage *message);
306 /* This is called for each unit type and should be used to
307 * enumerate existing devices and load them. However,
308 * everything that is loaded here should still stay in
309 * inactive state. It is the job of the coldplug() call above
310 * to put the units into the initial state. */
311 int (*enumerate)(Manager *m);
313 /* Type specific cleanups. */
314 void (*shutdown)(Manager *m);
316 /* Can units of this type have multiple names? */
319 /* If true units of this types can never have "Requires"
320 * dependencies, because state changes can only be observed,
324 /* Instances make no sense for this type */
327 /* Exclude this type from snapshots */
330 /* Exclude from automatic gc */
333 /* Exclude from isolation requests */
337 extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX];
339 #define UNIT_VTABLE(u) unit_vtable[(u)->meta.type]
341 /* For casting a unit into the various unit types */
342 #define DEFINE_CAST(UPPERCASE, MixedCase) \
343 static inline MixedCase* UPPERCASE(Unit *u) { \
344 if (_unlikely_(!u || u->meta.type != UNIT_##UPPERCASE)) \
347 return (MixedCase*) u; \
350 /* For casting the various unit types into a unit */
351 #define UNIT(u) ((Unit*) (&(u)->meta))
353 DEFINE_CAST(SOCKET, Socket);
354 DEFINE_CAST(TIMER, Timer);
355 DEFINE_CAST(SERVICE, Service);
356 DEFINE_CAST(TARGET, Target);
357 DEFINE_CAST(DEVICE, Device);
358 DEFINE_CAST(MOUNT, Mount);
359 DEFINE_CAST(AUTOMOUNT, Automount);
360 DEFINE_CAST(SNAPSHOT, Snapshot);
361 DEFINE_CAST(SWAP, Swap);
362 DEFINE_CAST(PATH, Path);
364 Unit *unit_new(Manager *m);
365 void unit_free(Unit *u);
367 int unit_add_name(Unit *u, const char *name);
369 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference);
370 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
371 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
373 int unit_add_exec_dependencies(Unit *u, ExecContext *c);
375 int unit_add_cgroup(Unit *u, CGroupBonding *b);
376 int unit_add_cgroup_from_text(Unit *u, const char *name);
377 int unit_add_default_cgroup(Unit *u);
378 CGroupBonding* unit_get_default_cgroup(Unit *u);
380 int unit_choose_id(Unit *u, const char *name);
381 int unit_set_description(Unit *u, const char *description);
383 bool unit_check_gc(Unit *u);
385 void unit_add_to_load_queue(Unit *u);
386 void unit_add_to_dbus_queue(Unit *u);
387 void unit_add_to_cleanup_queue(Unit *u);
388 void unit_add_to_gc_queue(Unit *u);
390 int unit_merge(Unit *u, Unit *other);
391 int unit_merge_by_name(Unit *u, const char *other);
393 Unit *unit_follow_merge(Unit *u);
395 int unit_load_fragment_and_dropin(Unit *u);
396 int unit_load_fragment_and_dropin_optional(Unit *u);
397 int unit_load_nop(Unit *u);
398 int unit_load(Unit *unit);
400 const char *unit_description(Unit *u);
402 bool unit_has_name(Unit *u, const char *name);
404 UnitActiveState unit_active_state(Unit *u);
406 const char* unit_sub_state_to_string(Unit *u);
408 void unit_dump(Unit *u, FILE *f, const char *prefix);
410 bool unit_can_reload(Unit *u);
411 bool unit_can_start(Unit *u);
413 int unit_start(Unit *u);
414 int unit_stop(Unit *u);
415 int unit_reload(Unit *u);
417 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns);
419 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w);
420 void unit_unwatch_fd(Unit *u, Watch *w);
422 int unit_watch_pid(Unit *u, pid_t pid);
423 void unit_unwatch_pid(Unit *u, pid_t pid);
425 int unit_watch_timer(Unit *u, usec_t delay, Watch *w);
426 void unit_unwatch_timer(Unit *u, Watch *w);
428 int unit_watch_bus_name(Unit *u, const char *name);
429 void unit_unwatch_bus_name(Unit *u, const char *name);
431 bool unit_job_is_applicable(Unit *u, JobType j);
433 int set_unit_path(const char *p);
435 char *unit_dbus_path(Unit *u);
437 int unit_load_related_unit(Unit *u, const char *type, Unit **_found);
438 int unit_get_related_unit(Unit *u, const char *type, Unit **_found);
440 char *unit_name_printf(Unit *u, const char* text);
441 char *unit_full_printf(Unit *u, const char *text);
442 char **unit_full_printf_strv(Unit *u, char **l);
444 bool unit_can_serialize(Unit *u);
445 int unit_serialize(Unit *u, FILE *f, FDSet *fds);
446 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *value, ...) _printf_attr_(4,5);
447 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value);
448 int unit_deserialize(Unit *u, FILE *f, FDSet *fds);
450 int unit_add_node_link(Unit *u, const char *what, bool wants);
452 int unit_coldplug(Unit *u);
454 const char *unit_type_to_string(UnitType i);
455 UnitType unit_type_from_string(const char *s);
457 const char *unit_load_state_to_string(UnitLoadState i);
458 UnitLoadState unit_load_state_from_string(const char *s);
460 const char *unit_active_state_to_string(UnitActiveState i);
461 UnitActiveState unit_active_state_from_string(const char *s);
463 const char *unit_dependency_to_string(UnitDependency i);
464 UnitDependency unit_dependency_from_string(const char *s);
466 const char *kill_mode_to_string(KillMode k);
467 KillMode kill_mode_from_string(const char *s);