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
66 _UNIT_TYPE_INVALID = -1
75 _UNIT_LOAD_STATE_INVALID = -1
78 enum UnitActiveState {
80 UNIT_ACTIVE_RELOADING,
84 _UNIT_ACTIVE_STATE_MAX,
85 _UNIT_ACTIVE_STATE_INVALID = -1
88 static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
89 return t == UNIT_ACTIVE || t == UNIT_ACTIVE_RELOADING;
92 static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
93 return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_ACTIVE_RELOADING;
96 static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
97 return t == UNIT_INACTIVE || t == UNIT_DEACTIVATING;
100 enum UnitDependency {
101 /* Positive dependencies */
103 UNIT_REQUIRES_OVERRIDABLE,
105 UNIT_REQUISITE_OVERRIDABLE,
108 /* Inverse of the above */
109 UNIT_REQUIRED_BY, /* inverse of 'requires' and 'requisite' is 'required_by' */
110 UNIT_REQUIRED_BY_OVERRIDABLE, /* inverse of 'soft_requires' and 'soft_requisite' is 'soft_required_by' */
111 UNIT_WANTED_BY, /* inverse of 'wants' */
113 /* Negative dependencies */
114 UNIT_CONFLICTS, /* inverse of 'conflicts' is 'conflicts' */
117 UNIT_BEFORE, /* inverse of 'before' is 'after' and vice versa */
120 /* Reference information for GC logic */
121 UNIT_REFERENCES, /* Inverse of 'references' is 'referenced_by' */
124 _UNIT_DEPENDENCY_MAX,
125 _UNIT_DEPENDENCY_INVALID = -1
136 UnitLoadState load_state;
139 char *id; /* One name is special because we use it for identification. Points to an entry in the names set */
143 Set *dependencies[_UNIT_DEPENDENCY_MAX];
146 char *fragment_path; /* if loaded from a config file this is the primary path to it */
148 /* If there is something to do with this unit, then this is
152 usec_t inactive_exit_timestamp;
153 usec_t active_enter_timestamp;
154 usec_t active_exit_timestamp;
155 usec_t inactive_enter_timestamp;
157 /* Counterparts in the cgroup filesystem */
158 CGroupBonding *cgroup_bondings;
161 LIST_FIELDS(Meta, units_per_type);
164 LIST_FIELDS(Meta, load_queue);
167 LIST_FIELDS(Meta, dbus_queue);
170 LIST_FIELDS(Meta, cleanup_queue);
173 LIST_FIELDS(Meta, gc_queue);
175 /* Used during GC sweeps */
178 /* If we go down, pull down everything that depends on us, too */
181 /* Garbage collect us we nobody wants or requires us anymore */
182 bool stop_when_unneeded;
184 bool in_load_queue:1;
185 bool in_dbus_queue:1;
186 bool in_cleanup_queue:1;
189 bool sent_dbus_new_signal:1;
198 #include "automount.h"
199 #include "snapshot.h"
218 /* This should reset all type-specific variables. This should
219 * not allocate memory, and is called with zero-initialized
220 * data. It should hence only initialize variables that need
222 void (*init)(Unit *u);
224 /* This should free all type-specific variables. It should be
226 void (*done)(Unit *u);
228 /* Actually load data from disk. This may fail, and should set
229 * load_state to UNIT_LOADED, UNIT_MERGED or leave it at
230 * UNIT_STUB if no configuration could be found. */
231 int (*load)(Unit *u);
233 /* If a a lot of units got created via enumerate(), this is
234 * where to actually set the state and call unit_notify(). */
235 int (*coldplug)(Unit *u);
237 void (*dump)(Unit *u, FILE *f, const char *prefix);
239 int (*start)(Unit *u);
240 int (*stop)(Unit *u);
241 int (*reload)(Unit *u);
243 bool (*can_reload)(Unit *u);
245 /* Write all data that cannot be restored from other sources
246 * away using unit_serialize_item() */
247 int (*serialize)(Unit *u, FILE *f, FDSet *fds);
249 /* Restore one item from the serialization */
250 int (*deserialize_item)(Unit *u, const char *key, const char *data, FDSet *fds);
252 /* Boils down the more complex internal state of this unit to
253 * a simpler one that the engine can understand */
254 UnitActiveState (*active_state)(Unit *u);
256 /* Returns the substate specific to this unit type as
257 * string. This is purely information so that we can give the
258 * user a more finegrained explanation in which actual state a
260 const char* (*sub_state_to_string)(Unit *u);
262 /* Return true when there is reason to keep this entry around
263 * even nothing references it and it isn't active in any
265 bool (*check_gc)(Unit *u);
267 /* Return true when this unit is suitable for snapshotting */
268 bool (*check_snapshot)(Unit *u);
270 void (*fd_event)(Unit *u, int fd, uint32_t events, Watch *w);
271 void (*sigchld_event)(Unit *u, pid_t pid, int code, int status);
272 void (*timer_event)(Unit *u, uint64_t n_elapsed, Watch *w);
274 /* Called whenever any of the cgroups this unit watches for
276 void (*cgroup_notify_empty)(Unit *u);
278 /* Called whenever a name thus Unit registered for comes or
280 void (*bus_name_owner_change)(Unit *u, const char *name, const char *old_owner, const char *new_owner);
282 /* Called whenever a bus PID lookup finishes */
283 void (*bus_query_pid_done)(Unit *u, const char *name, pid_t pid);
285 /* Called for each message received on the bus */
286 DBusHandlerResult (*bus_message_handler)(Unit *u, DBusMessage *message);
288 /* This is called for each unit type and should be used to
289 * enumerate existing devices and load them. However,
290 * everything that is loaded here should still stay in
291 * inactive state. It is the job of the coldplug() call above
292 * to put the units into the initial state. */
293 int (*enumerate)(Manager *m);
295 /* Type specific cleanups. */
296 void (*shutdown)(Manager *m);
298 /* Can units of this type have multiple names? */
301 /* If true units of this types can never have "Requires"
302 * dependencies, because state changes can only be observed,
306 /* Instances make no sense for this type */
309 /* Exclude this type from snapshots */
312 /* Exclude from automatic gc */
315 /* Exclude from isolation requests */
319 extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX];
321 #define UNIT_VTABLE(u) unit_vtable[(u)->meta.type]
323 /* For casting a unit into the various unit types */
324 #define DEFINE_CAST(UPPERCASE, MixedCase) \
325 static inline MixedCase* UPPERCASE(Unit *u) { \
326 if (!u || u->meta.type != UNIT_##UPPERCASE) \
329 return (MixedCase*) u; \
332 /* For casting the various unit types into a unit */
333 #define UNIT(u) ((Unit*) (u))
335 DEFINE_CAST(SOCKET, Socket);
336 DEFINE_CAST(TIMER, Timer);
337 DEFINE_CAST(SERVICE, Service);
338 DEFINE_CAST(TARGET, Target);
339 DEFINE_CAST(DEVICE, Device);
340 DEFINE_CAST(MOUNT, Mount);
341 DEFINE_CAST(AUTOMOUNT, Automount);
342 DEFINE_CAST(SNAPSHOT, Snapshot);
343 DEFINE_CAST(SWAP, Swap);
345 Unit *unit_new(Manager *m);
346 void unit_free(Unit *u);
348 int unit_add_name(Unit *u, const char *name);
350 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference);
351 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
352 int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
354 int unit_add_exec_dependencies(Unit *u, ExecContext *c);
356 int unit_add_cgroup(Unit *u, CGroupBonding *b);
357 int unit_add_cgroup_from_text(Unit *u, const char *name);
358 int unit_add_default_cgroup(Unit *u);
359 CGroupBonding* unit_get_default_cgroup(Unit *u);
361 int unit_choose_id(Unit *u, const char *name);
362 int unit_set_description(Unit *u, const char *description);
364 bool unit_check_gc(Unit *u);
366 void unit_add_to_load_queue(Unit *u);
367 void unit_add_to_dbus_queue(Unit *u);
368 void unit_add_to_cleanup_queue(Unit *u);
369 void unit_add_to_gc_queue(Unit *u);
371 int unit_merge(Unit *u, Unit *other);
372 int unit_merge_by_name(Unit *u, const char *other);
374 Unit *unit_follow_merge(Unit *u);
376 int unit_load_fragment_and_dropin(Unit *u);
377 int unit_load_fragment_and_dropin_optional(Unit *u);
378 int unit_load_nop(Unit *u);
379 int unit_load(Unit *unit);
381 const char *unit_description(Unit *u);
383 bool unit_has_name(Unit *u, const char *name);
385 UnitActiveState unit_active_state(Unit *u);
387 const char* unit_sub_state_to_string(Unit *u);
389 void unit_dump(Unit *u, FILE *f, const char *prefix);
391 bool unit_can_reload(Unit *u);
392 bool unit_can_start(Unit *u);
394 int unit_start(Unit *u);
395 int unit_stop(Unit *u);
396 int unit_reload(Unit *u);
398 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns);
400 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w);
401 void unit_unwatch_fd(Unit *u, Watch *w);
403 int unit_watch_pid(Unit *u, pid_t pid);
404 void unit_unwatch_pid(Unit *u, pid_t pid);
406 int unit_watch_timer(Unit *u, usec_t delay, Watch *w);
407 void unit_unwatch_timer(Unit *u, Watch *w);
409 int unit_watch_bus_name(Unit *u, const char *name);
410 void unit_unwatch_bus_name(Unit *u, const char *name);
412 bool unit_job_is_applicable(Unit *u, JobType j);
414 int set_unit_path(const char *p);
416 char *unit_dbus_path(Unit *u);
418 int unit_load_related_unit(Unit *u, const char *type, Unit **_found);
419 int unit_get_related_unit(Unit *u, const char *type, Unit **_found);
421 char *unit_name_printf(Unit *u, const char* text);
422 char *unit_full_printf(Unit *u, const char *text);
423 char **unit_full_printf_strv(Unit *u, char **l);
425 bool unit_can_serialize(Unit *u);
426 int unit_serialize(Unit *u, FILE *f, FDSet *fds);
427 void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *value, ...) _printf_attr(4,5);
428 void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value);
429 int unit_deserialize(Unit *u, FILE *f, FDSet *fds);
431 int unit_add_node_link(Unit *u, const char *what, bool wants);
433 const char *unit_type_to_string(UnitType i);
434 UnitType unit_type_from_string(const char *s);
436 const char *unit_load_state_to_string(UnitLoadState i);
437 UnitLoadState unit_load_state_from_string(const char *s);
439 const char *unit_active_state_to_string(UnitActiveState i);
440 UnitActiveState unit_active_state_from_string(const char *s);
442 const char *unit_dependency_to_string(UnitDependency i);
443 UnitDependency unit_dependency_from_string(const char *s);
445 const char *kill_mode_to_string(KillMode k);
446 KillMode kill_mode_from_string(const char *s);