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 (20*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
65 _UNIT_TYPE_INVALID = -1
74 _UNIT_LOAD_STATE_INVALID = -1
77 enum UnitActiveState {
79 UNIT_ACTIVE_RELOADING,
83 _UNIT_ACTIVE_STATE_MAX,
84 _UNIT_ACTIVE_STATE_INVALID = -1
87 static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
88 return t == UNIT_ACTIVE || t == UNIT_ACTIVE_RELOADING;
91 static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
92 return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_ACTIVE_RELOADING;
95 static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
96 return t == UNIT_INACTIVE || t == UNIT_DEACTIVATING;
100 /* Positive dependencies */
102 UNIT_REQUIRES_OVERRIDABLE,
104 UNIT_REQUISITE_OVERRIDABLE,
107 /* Inverse of the above */
108 UNIT_REQUIRED_BY, /* inverse of 'requires' and 'requisite' is 'required_by' */
109 UNIT_REQUIRED_BY_OVERRIDABLE, /* inverse of 'soft_requires' and 'soft_requisite' is 'soft_required_by' */
110 UNIT_WANTED_BY, /* inverse of 'wants' */
112 /* Negative dependencies */
113 UNIT_CONFLICTS, /* inverse of 'conflicts' is 'conflicts' */
116 UNIT_BEFORE, /* inverse of 'before' is 'after' and vice versa */
119 /* Reference information for GC logic */
120 UNIT_REFERENCES, /* Inverse of 'references' is 'referenced_by' */
123 _UNIT_DEPENDENCY_MAX,
124 _UNIT_DEPENDENCY_INVALID = -1
135 UnitLoadState load_state;
138 char *id; /* One name is special because we use it for identification. Points to an entry in the names set */
142 Set *dependencies[_UNIT_DEPENDENCY_MAX];
145 char *fragment_path; /* if loaded from a config file this is the primary path to it */
147 /* If there is something to do with this unit, then this is
151 usec_t active_enter_timestamp;
152 usec_t active_exit_timestamp;
154 /* Counterparts in the cgroup filesystem */
155 CGroupBonding *cgroup_bondings;
158 LIST_FIELDS(Meta, units_per_type);
161 LIST_FIELDS(Meta, load_queue);
164 LIST_FIELDS(Meta, dbus_queue);
167 LIST_FIELDS(Meta, cleanup_queue);
170 LIST_FIELDS(Meta, gc_queue);
172 /* Used during GC sweeps */
175 /* If we go down, pull down everything that depends on us, too */
178 /* Garbage collect us we nobody wants or requires us anymore */
179 bool stop_when_unneeded;
181 bool in_load_queue:1;
182 bool in_dbus_queue:1;
183 bool in_cleanup_queue:1;
186 bool sent_dbus_new_signal:1;
195 #include "automount.h"
196 #include "snapshot.h"
213 /* This should reset all type-specific variables. This should
214 * not allocate memory, and is called with zero-initialized
215 * data. It should hence only initialize variables that need
217 void (*init)(Unit *u);
219 /* This should free all type-specific variables. It should be
221 void (*done)(Unit *u);
223 /* Actually load data from disk. This may fail, and should set
224 * load_state to UNIT_LOADED, UNIT_MERGED or leave it at
225 * UNIT_STUB if no configuration could be found. */
226 int (*load)(Unit *u);
228 /* If a a lot of units got created via enumerate(), this is
229 * where to actually set the state and call unit_notify(). */
230 int (*coldplug)(Unit *u);
232 void (*dump)(Unit *u, FILE *f, const char *prefix);
234 int (*start)(Unit *u);
235 int (*stop)(Unit *u);
236 int (*reload)(Unit *u);
238 bool (*can_reload)(Unit *u);
240 /* Write all data that cannot be restored from other sources
241 * away using unit_serialize_item() */
242 int (*serialize)(Unit *u, FILE *f, FDSet *fds);
244 /* Restore one item from the serialization */
245 int (*deserialize_item)(Unit *u, const char *key, const char *data, FDSet *fds);
247 /* Boils down the more complex internal state of this unit to
248 * a simpler one that the engine can understand */
249 UnitActiveState (*active_state)(Unit *u);
251 /* Returns the substate specific to this unit type as
252 * string. This is purely information so that we can give the
253 * user a more finegrained explanation in which actual state a
255 const char* (*sub_state_to_string)(Unit *u);
257 /* Return true when there is reason to keep this entry around
258 * even nothing references it and it isn't active in any
260 bool (*check_gc)(Unit *u);
262 /* Return true when this unit is suitable for snapshotting */
263 bool (*check_snapshot)(Unit *u);
265 void (*fd_event)(Unit *u, int fd, uint32_t events, Watch *w);
266 void (*sigchld_event)(Unit *u, pid_t pid, int code, int status);
267 void (*timer_event)(Unit *u, uint64_t n_elapsed, Watch *w);
269 /* Called whenever any of the cgroups this unit watches for
271 void (*cgroup_notify_empty)(Unit *u);
273 /* Called whenever a name thus Unit registered for comes or
275 void (*bus_name_owner_change)(Unit *u, const char *name, const char *old_owner, const char *new_owner);
277 /* Called whenever a bus PID lookup finishes */
278 void (*bus_query_pid_done)(Unit *u, const char *name, pid_t pid);
280 /* Called for each message received on the bus */
281 DBusHandlerResult (*bus_message_handler)(Unit *u, DBusMessage *message);
283 /* This is called for each unit type and should be used to
284 * enumerate existing devices and load them. However,
285 * everything that is loaded here should still stay in
286 * inactive state. It is the job of the coldplug() call above
287 * to put the units into the initial state. */
288 int (*enumerate)(Manager *m);
290 /* Type specific cleanups. */
291 void (*shutdown)(Manager *m);
293 /* Can units of this type have multiple names? */
296 /* If true units of this types can never have "Requires"
297 * dependencies, because state changes can only be observed,
301 /* Instances make no sense for this type */
304 /* Exclude this type from snapshots */
307 /* Exclude from automatic gc */
310 /* Exclude from isolation requests */
314 extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX];
316 #define UNIT_VTABLE(u) unit_vtable[(u)->meta.type]
318 /* For casting a unit into the various unit types */
319 #define DEFINE_CAST(UPPERCASE, MixedCase) \
320 static inline MixedCase* UPPERCASE(Unit *u) { \
321 if (!u || u->meta.type != UNIT_##UPPERCASE) \
324 return (MixedCase*) u; \
327 /* For casting the various unit types into a unit */
328 #define UNIT(u) ((Unit*) (u))
330 DEFINE_CAST(SOCKET, Socket);
331 DEFINE_CAST(TIMER, Timer);
332 DEFINE_CAST(SERVICE, Service);
333 DEFINE_CAST(TARGET, Target);
334 DEFINE_CAST(DEVICE, Device);
335 DEFINE_CAST(MOUNT, Mount);
336 DEFINE_CAST(AUTOMOUNT, Automount);
337 DEFINE_CAST(SNAPSHOT, Snapshot);
339 Unit *unit_new(Manager *m);
340 void unit_free(Unit *u);
342 int unit_add_name(Unit *u, const char *name);
344 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference);
345 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
346 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
348 int unit_add_exec_dependencies(Unit *u, ExecContext *c);
350 int unit_add_cgroup(Unit *u, CGroupBonding *b);
351 int unit_add_cgroup_from_text(Unit *u, const char *name);
352 int unit_add_default_cgroup(Unit *u);
353 CGroupBonding* unit_get_default_cgroup(Unit *u);
355 int unit_choose_id(Unit *u, const char *name);
356 int unit_set_description(Unit *u, const char *description);
358 bool unit_check_gc(Unit *u);
360 void unit_add_to_load_queue(Unit *u);
361 void unit_add_to_dbus_queue(Unit *u);
362 void unit_add_to_cleanup_queue(Unit *u);
363 void unit_add_to_gc_queue(Unit *u);
365 int unit_merge(Unit *u, Unit *other);
366 int unit_merge_by_name(Unit *u, const char *other);
368 Unit *unit_follow_merge(Unit *u);
370 int unit_load_fragment_and_dropin(Unit *u);
371 int unit_load_fragment_and_dropin_optional(Unit *u);
372 int unit_load_nop(Unit *u);
373 int unit_load(Unit *unit);
375 const char *unit_description(Unit *u);
377 bool unit_has_name(Unit *u, const char *name);
379 UnitActiveState unit_active_state(Unit *u);
381 const char* unit_sub_state_to_string(Unit *u);
383 void unit_dump(Unit *u, FILE *f, const char *prefix);
385 bool unit_can_reload(Unit *u);
386 bool unit_can_start(Unit *u);
388 int unit_start(Unit *u);
389 int unit_stop(Unit *u);
390 int unit_reload(Unit *u);
392 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns);
394 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w);
395 void unit_unwatch_fd(Unit *u, Watch *w);
397 int unit_watch_pid(Unit *u, pid_t pid);
398 void unit_unwatch_pid(Unit *u, pid_t pid);
400 int unit_watch_timer(Unit *u, usec_t delay, Watch *w);
401 void unit_unwatch_timer(Unit *u, Watch *w);
403 int unit_watch_bus_name(Unit *u, const char *name);
404 void unit_unwatch_bus_name(Unit *u, const char *name);
406 bool unit_job_is_applicable(Unit *u, JobType j);
408 int set_unit_path(const char *p);
410 char *unit_dbus_path(Unit *u);
412 int unit_load_related_unit(Unit *u, const char *type, Unit **_found);
413 int unit_get_related_unit(Unit *u, const char *type, Unit **_found);
415 char *unit_name_printf(Unit *u, const char* text);
416 char *unit_full_printf(Unit *u, const char *text);
417 char **unit_full_printf_strv(Unit *u, char **l);
419 bool unit_can_serialize(Unit *u);
420 int unit_serialize(Unit *u, FILE *f, FDSet *fds);
421 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *value, ...) _printf_attr(4,5);
422 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value);
423 int unit_deserialize(Unit *u, FILE *f, FDSet *fds);
425 const char *unit_type_to_string(UnitType i);
426 UnitType unit_type_from_string(const char *s);
428 const char *unit_load_state_to_string(UnitLoadState i);
429 UnitLoadState unit_load_state_from_string(const char *s);
431 const char *unit_active_state_to_string(UnitActiveState i);
432 UnitActiveState unit_active_state_from_string(const char *s);
434 const char *unit_dependency_to_string(UnitDependency i);
435 UnitDependency unit_dependency_from_string(const char *s);
437 const char *kill_mode_to_string(KillMode k);
438 KillMode kill_mode_from_string(const char *s);