unit.h revision 613b411c947635136637f8cdd66b94512f761eab
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni#pragma once
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni/***
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni This file is part of systemd.
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni Copyright 2010 Lennart Poettering
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni systemd is free software; you can redistribute it and/or modify it
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni under the terms of the GNU Lesser General Public License as published by
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni the Free Software Foundation; either version 2.1 of the License, or
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni (at your option) any later version.
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni systemd is distributed in the hope that it will be useful, but
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni WITHOUT ANY WARRANTY; without even the implied warranty of
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni Lesser General Public License for more details.
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni You should have received a copy of the GNU Lesser General Public License
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni along with systemd; If not, see <http://www.gnu.org/licenses/>.
7741d5b589048a915ad3baea77b81cb81b2dbe4fCraig McDonnell***/
7741d5b589048a915ad3baea77b81cb81b2dbe4fCraig McDonnell
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include <stdbool.h>
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include <stdlib.h>
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include <unistd.h>
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantonitypedef struct Unit Unit;
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantonitypedef struct UnitVTable UnitVTable;
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantonitypedef enum UnitActiveState UnitActiveState;
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantonitypedef enum UnitDependency UnitDependency;
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantonitypedef struct UnitRef UnitRef;
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantonitypedef struct UnitStatusMessageFormats UnitStatusMessageFormats;
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "sd-event.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "set.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "util.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "list.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "socket-util.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "execute.h"
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni#include "cgroup.h"
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni#include "condition.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "install.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni#include "unit-name.h"
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantonienum UnitActiveState {
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni UNIT_ACTIVE,
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni UNIT_RELOADING,
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni UNIT_INACTIVE,
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni UNIT_FAILED,
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni UNIT_ACTIVATING,
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni UNIT_DEACTIVATING,
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni _UNIT_ACTIVE_STATE_MAX,
12e7a579c676ce6e5d1a822557813542d7687d11Diego Colantoni _UNIT_ACTIVE_STATE_INVALID = -1
306fc147c159b5ea1a92aa9466cd30a9bf743fe0Craig McDonnell};
4d3e11a2177a45225341ff99c71d168f23ef3b98Craig McDonnell
4d3e11a2177a45225341ff99c71d168f23ef3b98Craig McDonnellstatic inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
4d3e11a2177a45225341ff99c71d168f23ef3b98Craig McDonnell return t == UNIT_ACTIVE || t == UNIT_RELOADING;
4d3e11a2177a45225341ff99c71d168f23ef3b98Craig McDonnell}
4d3e11a2177a45225341ff99c71d168f23ef3b98Craig McDonnell
4d3e11a2177a45225341ff99c71d168f23ef3b98Craig McDonnellstatic inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
4d3e11a2177a45225341ff99c71d168f23ef3b98Craig McDonnell return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_RELOADING;
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni}
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantonistatic inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
6a2ae9c7fb4d2c40d75cab0edaf940f22c18224fDiego Colantoni return t == UNIT_INACTIVE || t == UNIT_FAILED || t == UNIT_DEACTIVATING;
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni}
7c51d54f23c5581d2cf894f9eafb9798e3febd22Diego Colantoni
7741d5b589048a915ad3baea77b81cb81b2dbe4fCraig McDonnellstatic inline bool UNIT_IS_INACTIVE_OR_FAILED(UnitActiveState t) {
7741d5b589048a915ad3baea77b81cb81b2dbe4fCraig McDonnell return t == UNIT_INACTIVE || t == UNIT_FAILED;
}
enum UnitDependency {
/* Positive dependencies */
UNIT_REQUIRES,
UNIT_REQUIRES_OVERRIDABLE,
UNIT_REQUISITE,
UNIT_REQUISITE_OVERRIDABLE,
UNIT_WANTS,
UNIT_BINDS_TO,
UNIT_PART_OF,
/* Inverse of the above */
UNIT_REQUIRED_BY, /* inverse of 'requires' and 'requisite' is 'required_by' */
UNIT_REQUIRED_BY_OVERRIDABLE, /* inverse of 'requires_overridable' and 'requisite_overridable' is 'soft_required_by' */
UNIT_WANTED_BY, /* inverse of 'wants' */
UNIT_BOUND_BY, /* inverse of 'binds_to' */
UNIT_CONSISTS_OF, /* inverse of 'part_of' */
/* Negative dependencies */
UNIT_CONFLICTS, /* inverse of 'conflicts' is 'conflicted_by' */
UNIT_CONFLICTED_BY,
/* Order */
UNIT_BEFORE, /* inverse of 'before' is 'after' and vice versa */
UNIT_AFTER,
/* On Failure */
UNIT_ON_FAILURE,
/* Triggers (i.e. a socket triggers a service) */
UNIT_TRIGGERS,
UNIT_TRIGGERED_BY,
/* Propagate reloads */
UNIT_PROPAGATES_RELOAD_TO,
UNIT_RELOAD_PROPAGATED_FROM,
/* Joins namespace of */
UNIT_JOINS_NAMESPACE_OF,
/* Reference information for GC logic */
UNIT_REFERENCES, /* Inverse of 'references' is 'referenced_by' */
UNIT_REFERENCED_BY,
_UNIT_DEPENDENCY_MAX,
_UNIT_DEPENDENCY_INVALID = -1
};
#include "manager.h"
#include "job.h"
struct UnitRef {
/* Keeps tracks of references to a unit. This is useful so
* that we can merge two units if necessary and correct all
* references to them */
Unit* unit;
LIST_FIELDS(UnitRef, refs);
};
struct Unit {
Manager *manager;
UnitType type;
UnitLoadState load_state;
Unit *merged_into;
char *id; /* One name is special because we use it for identification. Points to an entry in the names set */
char *instance;
Set *names;
Set *dependencies[_UNIT_DEPENDENCY_MAX];
char **requires_mounts_for;
char *description;
char **documentation;
char *fragment_path; /* if loaded from a config file this is the primary path to it */
char *source_path; /* if converted, the source file */
char **dropin_paths;
usec_t fragment_mtime;
usec_t source_mtime;
usec_t dropin_mtime;
/* If there is something to do with this unit, then this is the installed job for it */
Job *job;
/* JOB_NOP jobs are special and can be installed without disturbing the real job. */
Job *nop_job;
usec_t job_timeout;
/* References to this */
LIST_HEAD(UnitRef, refs);
/* Conditions to check */
LIST_HEAD(Condition, conditions);
dual_timestamp condition_timestamp;
dual_timestamp inactive_exit_timestamp;
dual_timestamp active_enter_timestamp;
dual_timestamp active_exit_timestamp;
dual_timestamp inactive_enter_timestamp;
/* Counterparts in the cgroup filesystem */
char *cgroup_path;
CGroupControllerMask cgroup_mask;
CGroupControllerMask cgroup_members_mask;
UnitRef slice;
/* Per type list */
LIST_FIELDS(Unit, units_by_type);
/* All units which have requires_mounts_for set */
LIST_FIELDS(Unit, has_requires_mounts_for);
/* Load queue */
LIST_FIELDS(Unit, load_queue);
/* D-Bus queue */
LIST_FIELDS(Unit, dbus_queue);
/* Cleanup queue */
LIST_FIELDS(Unit, cleanup_queue);
/* GC queue */
LIST_FIELDS(Unit, gc_queue);
/* CGroup realize members queue */
LIST_FIELDS(Unit, cgroup_queue);
/* Used during GC sweeps */
unsigned gc_marker;
/* When deserializing, temporarily store the job type for this
* unit here, if there was a job scheduled.
* Only for deserializing from a legacy version. New style uses full
* serialized jobs. */
int deserialized_job; /* This is actually of type JobType */
/* Error code when we didn't manage to load the unit (negative) */
int load_error;
/* Cached unit file state */
UnitFileState unit_file_state;
/* Garbage collect us we nobody wants or requires us anymore */
bool stop_when_unneeded;
/* Create default dependencies */
bool default_dependencies;
/* Refuse manual starting, allow starting only indirectly via dependency. */
bool refuse_manual_start;
/* Don't allow the user to stop this unit manually, allow stopping only indirectly via dependency. */
bool refuse_manual_stop;
/* Allow isolation requests */
bool allow_isolate;
/* How to start OnFailure units */
JobMode on_failure_job_mode;
/* Ignore this unit when isolating */
bool ignore_on_isolate;
/* Ignore this unit when snapshotting */
bool ignore_on_snapshot;
/* Did the last condition check succeed? */
bool condition_result;
/* Is this a transient unit? */
bool transient;
bool in_load_queue:1;
bool in_dbus_queue:1;
bool in_cleanup_queue:1;
bool in_gc_queue:1;
bool in_cgroup_queue:1;
bool sent_dbus_new_signal:1;
bool no_gc:1;
bool in_audit:1;
bool cgroup_realized:1;
};
struct UnitStatusMessageFormats {
const char *starting_stopping[2];
const char *finished_start_job[_JOB_RESULT_MAX];
const char *finished_stop_job[_JOB_RESULT_MAX];
};
typedef enum UnitSetPropertiesMode {
UNIT_CHECK = 0,
UNIT_RUNTIME = 1,
UNIT_PERSISTENT = 2,
} UnitSetPropertiesMode;
#include "service.h"
#include "timer.h"
#include "socket.h"
#include "target.h"
#include "device.h"
#include "mount.h"
#include "automount.h"
#include "snapshot.h"
#include "swap.h"
#include "path.h"
#include "slice.h"
#include "scope.h"
struct UnitVTable {
/* How much memory does an object of this unit type need */
size_t object_size;
/* If greater than 0, the offset into the object where
* ExecContext is found, if the unit type has that */
size_t exec_context_offset;
/* If greater than 0, the offset into the object where
* CGroupContext is found, if the unit type has that */
size_t cgroup_context_offset;
/* If greater than 0, the offset into the object where
* KillContext is found, if the unit type has that */
size_t kill_context_offset;
/* If greater than 0, the offset into the object where the
* pointer to ExecRuntime is found, if the unit type has
* that */
size_t exec_runtime_offset;
/* The name of the configuration file section with the private settings of this unit*/
const char *private_section;
/* Config file sections this unit type understands, separated
* by NUL chars */
const char *sections;
/* This should reset all type-specific variables. This should
* not allocate memory, and is called with zero-initialized
* data. It should hence only initialize variables that need
* to be set != 0. */
void (*init)(Unit *u);
/* This should free all type-specific variables. It should be
* idempotent. */
void (*done)(Unit *u);
/* Actually load data from disk. This may fail, and should set
* load_state to UNIT_LOADED, UNIT_MERGED or leave it at
* UNIT_STUB if no configuration could be found. */
int (*load)(Unit *u);
/* If a lot of units got created via enumerate(), this is
* where to actually set the state and call unit_notify(). */
int (*coldplug)(Unit *u);
void (*dump)(Unit *u, FILE *f, const char *prefix);
int (*start)(Unit *u);
int (*stop)(Unit *u);
int (*reload)(Unit *u);
int (*kill)(Unit *u, KillWho w, int signo, sd_bus_error *error);
bool (*can_reload)(Unit *u);
/* Write all data that cannot be restored from other sources
* away using unit_serialize_item() */
int (*serialize)(Unit *u, FILE *f, FDSet *fds);
/* Restore one item from the serialization */
int (*deserialize_item)(Unit *u, const char *key, const char *data, FDSet *fds);
/* Try to match up fds with what we need for this unit */
int (*distribute_fds)(Unit *u, FDSet *fds);
/* Boils down the more complex internal state of this unit to
* a simpler one that the engine can understand */
UnitActiveState (*active_state)(Unit *u);
/* Returns the substate specific to this unit type as
* string. This is purely information so that we can give the
* user a more fine grained explanation in which actual state a
* unit is in. */
const char* (*sub_state_to_string)(Unit *u);
/* Return true when there is reason to keep this entry around
* even nothing references it and it isn't active in any
* way */
bool (*check_gc)(Unit *u);
/* Return true when this unit is suitable for snapshotting */
bool (*check_snapshot)(Unit *u);
/* Invoked on every child that died */
void (*sigchld_event)(Unit *u, pid_t pid, int code, int status);
/* Reset failed state if we are in failed state */
void (*reset_failed)(Unit *u);
/* Called whenever any of the cgroups this unit watches for
* ran empty */
void (*notify_cgroup_empty)(Unit *u);
/* Called whenever a process of this unit sends us a message */
void (*notify_message)(Unit *u, pid_t pid, char **tags);
/* Called whenever a name this Unit registered for comes or
* goes away. */
void (*bus_name_owner_change)(Unit *u, const char *name, const char *old_owner, const char *new_owner);
/* Called for each property that is being set */
int (*bus_set_property)(Unit *u, const char *name, sd_bus_message *message, UnitSetPropertiesMode mode, sd_bus_error *error);
/* Called after at least one property got changed to apply the necessary change */
int (*bus_commit_properties)(Unit *u);
/* Return the unit this unit is following */
Unit *(*following)(Unit *u);
/* Return the set of units that are following each other */
int (*following_set)(Unit *u, Set **s);
/* Invoked each time a unit this unit is triggering changes
* state or gains/loses a job */
void (*trigger_notify)(Unit *u, Unit *trigger);
/* Called whenever CLOCK_REALTIME made a jump */
void (*time_change)(Unit *u);
/* This is called for each unit type and should be used to
* enumerate existing devices and load them. However,
* everything that is loaded here should still stay in
* inactive state. It is the job of the coldplug() call above
* to put the units into the initial state. */
int (*enumerate)(Manager *m);
/* Type specific cleanups. */
void (*shutdown)(Manager *m);
/* The interface name */
const char *bus_interface;
/* The bus vtable */
const sd_bus_vtable *bus_vtable;
/* strv list of changing properties */
const char * const * const bus_changing_properties;
/* The strings to print in status messages */
UnitStatusMessageFormats status_message_formats;
/* Can units of this type have multiple names? */
bool no_alias:1;
/* Instances make no sense for this type */
bool no_instances:1;
/* Exclude from automatic gc */
bool no_gc:1;
/* True if transient units of this type are OK */
bool can_transient:1;
};
extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX];
#define UNIT_VTABLE(u) unit_vtable[(u)->type]
/* For casting a unit into the various unit types */
#define DEFINE_CAST(UPPERCASE, MixedCase) \
static inline MixedCase* UPPERCASE(Unit *u) { \
if (_unlikely_(!u || u->type != UNIT_##UPPERCASE)) \
return NULL; \
\
return (MixedCase*) u; \
}
/* For casting the various unit types into a unit */
#define UNIT(u) (&(u)->meta)
#define UNIT_TRIGGER(u) ((Unit*) set_first((u)->dependencies[UNIT_TRIGGERS]))
DEFINE_CAST(SOCKET, Socket);
DEFINE_CAST(TIMER, Timer);
DEFINE_CAST(SERVICE, Service);
DEFINE_CAST(TARGET, Target);
DEFINE_CAST(DEVICE, Device);
DEFINE_CAST(MOUNT, Mount);
DEFINE_CAST(AUTOMOUNT, Automount);
DEFINE_CAST(SNAPSHOT, Snapshot);
DEFINE_CAST(SWAP, Swap);
DEFINE_CAST(PATH, Path);
DEFINE_CAST(SLICE, Slice);
DEFINE_CAST(SCOPE, Scope);
Unit *unit_new(Manager *m, size_t size);
void unit_free(Unit *u);
int unit_add_name(Unit *u, const char *name);
int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference);
int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference);
int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference);
int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *filename, bool add_reference);
int unit_add_two_dependencies_by_name_inverse(Unit *u, UnitDependency d, UnitDependency e, const char *name, const char *path, bool add_reference);
int unit_add_exec_dependencies(Unit *u, ExecContext *c);
int unit_choose_id(Unit *u, const char *name);
int unit_set_description(Unit *u, const char *description);
bool unit_check_gc(Unit *u);
void unit_add_to_load_queue(Unit *u);
void unit_add_to_dbus_queue(Unit *u);
void unit_add_to_cleanup_queue(Unit *u);
void unit_add_to_gc_queue(Unit *u);
int unit_merge(Unit *u, Unit *other);
int unit_merge_by_name(Unit *u, const char *other);
Unit *unit_follow_merge(Unit *u) _pure_;
int unit_load_fragment_and_dropin(Unit *u);
int unit_load_fragment_and_dropin_optional(Unit *u);
int unit_load(Unit *unit);
int unit_add_default_slice(Unit *u);
const char *unit_description(Unit *u) _pure_;
bool unit_has_name(Unit *u, const char *name);
UnitActiveState unit_active_state(Unit *u);
const char* unit_sub_state_to_string(Unit *u);
void unit_dump(Unit *u, FILE *f, const char *prefix);
bool unit_can_reload(Unit *u) _pure_;
bool unit_can_start(Unit *u) _pure_;
bool unit_can_isolate(Unit *u) _pure_;
int unit_start(Unit *u);
int unit_stop(Unit *u);
int unit_reload(Unit *u);
int unit_kill(Unit *u, KillWho w, int signo, sd_bus_error *error);
int unit_kill_common(Unit *u, KillWho who, int signo, pid_t main_pid, pid_t control_pid, sd_bus_error *error);
void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_success);
int unit_watch_pid(Unit *u, pid_t pid);
void unit_unwatch_pid(Unit *u, pid_t pid);
int unit_watch_bus_name(Unit *u, const char *name);
void unit_unwatch_bus_name(Unit *u, const char *name);
bool unit_job_is_applicable(Unit *u, JobType j);
int set_unit_path(const char *p);
char *unit_dbus_path(Unit *u);
int unit_load_related_unit(Unit *u, const char *type, Unit **_found);
bool unit_can_serialize(Unit *u) _pure_;
int unit_serialize(Unit *u, FILE *f, FDSet *fds, bool serialize_jobs);
void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *value, ...) _printf_(4,5);
void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value);
int unit_deserialize(Unit *u, FILE *f, FDSet *fds);
int unit_add_node_link(Unit *u, const char *what, bool wants);
int unit_coldplug(Unit *u);
void unit_status_printf(Unit *u, const char *status, const char *unit_status_msg_format) _printf_(3, 0);
bool unit_need_daemon_reload(Unit *u);
void unit_reset_failed(Unit *u);
Unit *unit_following(Unit *u);
int unit_following_set(Unit *u, Set **s);
const char *unit_slice_name(Unit *u);
bool unit_stop_pending(Unit *u) _pure_;
bool unit_inactive_or_pending(Unit *u) _pure_;
bool unit_active_or_pending(Unit *u);
int unit_add_default_target_dependency(Unit *u, Unit *target);
char *unit_default_cgroup_path(Unit *u);
void unit_start_on_failure(Unit *u);
void unit_trigger_notify(Unit *u);
UnitFileState unit_get_unit_file_state(Unit *u);
Unit* unit_ref_set(UnitRef *ref, Unit *u);
void unit_ref_unset(UnitRef *ref);
#define UNIT_DEREF(ref) ((ref).unit)
#define UNIT_ISSET(ref) (!!(ref).unit)
int unit_exec_context_defaults(Unit *u, ExecContext *c);
ExecContext *unit_get_exec_context(Unit *u) _pure_;
KillContext *unit_get_kill_context(Unit *u) _pure_;
CGroupContext *unit_get_cgroup_context(Unit *u) _pure_;
ExecRuntime *unit_get_exec_runtime(Unit *u) _pure_;
int unit_setup_exec_runtime(Unit *u);
int unit_write_drop_in(Unit *u, UnitSetPropertiesMode mode, const char *name, const char *data);
int unit_write_drop_in_format(Unit *u, UnitSetPropertiesMode mode, const char *name, const char *format, ...) _printf_(4,5);
int unit_write_drop_in_private(Unit *u, UnitSetPropertiesMode mode, const char *name, const char *data);
int unit_write_drop_in_private_format(Unit *u, UnitSetPropertiesMode mode, const char *name, const char *format, ...) _printf_(4,5);
int unit_remove_drop_in(Unit *u, UnitSetPropertiesMode mode, const char *name);
int unit_kill_context(Unit *u, KillContext *c, bool sigkill, pid_t main_pid, pid_t control_pid, bool main_pid_alien);
int unit_make_transient(Unit *u);
int unit_require_mounts_for(Unit *u, const char *path);
const char *unit_active_state_to_string(UnitActiveState i) _const_;
UnitActiveState unit_active_state_from_string(const char *s) _pure_;
const char *unit_dependency_to_string(UnitDependency i) _const_;
UnitDependency unit_dependency_from_string(const char *s) _pure_;
/* Macros which append UNIT= or USER_UNIT= to the message */
#define log_full_unit(level, unit, ...) log_meta_object(level, __FILE__, __LINE__, __func__, getpid() == 1 ? "UNIT=" : "USER_UNIT=", unit, __VA_ARGS__)
#define log_debug_unit(unit, ...) log_full_unit(LOG_DEBUG, unit, __VA_ARGS__)
#define log_info_unit(unit, ...) log_full_unit(LOG_INFO, unit, __VA_ARGS__)
#define log_notice_unit(unit, ...) log_full_unit(LOG_NOTICE, unit, __VA_ARGS__)
#define log_warning_unit(unit, ...) log_full_unit(LOG_WARNING, unit, __VA_ARGS__)
#define log_error_unit(unit, ...) log_full_unit(LOG_ERR, unit, __VA_ARGS__)
#define log_struct_unit(level, unit, ...) log_struct(level, getpid() == 1 ? "UNIT=%s" : "USER_UNIT=%s", unit, __VA_ARGS__)