unit.h revision bea355dac94e82697aa98e25d80ee4248263bf92
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
#pragma once
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
typedef struct Unit Unit;
typedef struct UnitVTable UnitVTable;
typedef enum UnitActiveState UnitActiveState;
typedef struct UnitRef UnitRef;
typedef struct UnitStatusMessageFormats UnitStatusMessageFormats;
#include "list.h"
#include "condition.h"
#include "install.h"
#include "unit-name.h"
#include "failure-action.h"
enum UnitActiveState {
UNIT_ACTIVE,
UNIT_RELOADING,
UNIT_INACTIVE,
UNIT_FAILED,
UNIT_ACTIVATING,
UNIT_DEACTIVATING,
_UNIT_ACTIVE_STATE_MAX,
_UNIT_ACTIVE_STATE_INVALID = -1
};
typedef enum KillOperation {
KILL_TERMINATE,
KILL_KILL,
KILL_ABORT,
_KILL_OPERATION_MAX,
_KILL_OPERATION_INVALID = -1
} KillOperation;
static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
return t == UNIT_ACTIVE || t == UNIT_RELOADING;
}
static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_RELOADING;
}
static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
return t == UNIT_INACTIVE || t == UNIT_FAILED || t == UNIT_DEACTIVATING;
}
static inline bool UNIT_IS_INACTIVE_OR_FAILED(UnitActiveState t) {
return t == UNIT_INACTIVE || t == UNIT_FAILED;
}
#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;
/* Job timeout and action to take */
usec_t job_timeout;
FailureAction job_timeout_action;
char *job_timeout_reboot_arg;
/* References to this */
LIST_HEAD(UnitRef, refs);
/* Conditions to check */
LIST_HEAD(Condition, conditions);
LIST_HEAD(Condition, asserts);
dual_timestamp condition_timestamp;
dual_timestamp assert_timestamp;
dual_timestamp inactive_exit_timestamp;
dual_timestamp active_enter_timestamp;
dual_timestamp active_exit_timestamp;
dual_timestamp inactive_enter_timestamp;
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);
/* PIDs we keep an eye on. Note that a unit might have many
* more, but these are the ones we care enough about to
* process SIGCHLD for */
Set *pids;
/* 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;
/* Make sure we never enter endless loops with the check unneeded logic */
RateLimit check_unneeded_ratelimit;
/* Cached unit file state and preset */
UnitFileState unit_file_state;
int unit_file_preset;
/* Where the cpuacct.usage cgroup counter was at the time the unit was started */
nsec_t cpuacct_usage_base;
/* Counterparts in the cgroup filesystem */
char *cgroup_path;
CGroupControllerMask cgroup_realized_mask;
CGroupControllerMask cgroup_subtree_mask;
CGroupControllerMask cgroup_members_mask;
/* How to start OnFailure units */
JobMode on_failure_job_mode;
/* 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;
/* 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;
bool assert_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;
bool cgroup_members_mask_valid:1;
bool cgroup_subtree_mask_valid:1;
/* Did we already invoke unit_coldplug() for this unit? */
bool coldplugged;
};
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 "socket.h"
#include "busname.h"
#include "target.h"
#include "snapshot.h"
#include "device.h"
#include "automount.h"
#include "swap.h"
#include "timer.h"
#include "slice.h"
#include "path.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);
/* When the unit is not running and no job for it queued we
* shall release its runtime resources */
void (*release_resources)(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, FDSet *fds);
/* 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);
int (*get_timeout)(Unit *u, uint64_t *timeout);
/* 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);
/* If this function is set and return false all jobs for units
* of this type will immediately fail. */
bool (*supported)(void);
/* The interface name */
const char *bus_interface;
/* The bus vtable */
const sd_bus_vtable *bus_vtable;
/* 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(SERVICE, Service);
DEFINE_CAST(SOCKET, Socket);
DEFINE_CAST(BUSNAME, BusName);
DEFINE_CAST(TARGET, Target);
DEFINE_CAST(SNAPSHOT, Snapshot);
DEFINE_CAST(DEVICE, Device);
DEFINE_CAST(MOUNT, Mount);
DEFINE_CAST(AUTOMOUNT, Automount);
DEFINE_CAST(SWAP, Swap);
DEFINE_CAST(TIMER, Timer);
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, CGroupContext *c);
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_all_pids(Unit *u);
void unit_unwatch_all_pids(Unit *u);
void unit_tidy_watch_pids(Unit *u, pid_t except1, pid_t except2);
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);
int unit_get_unit_file_preset(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_patch_contexts(Unit *u);
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, KillOperation k, 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);
bool unit_type_supported(UnitType t);
static inline bool unit_supported(Unit *u) {
return unit_type_supported(u->type);
}
void unit_warn_if_dir_nonempty(Unit *u, const char* where);
int unit_fail_if_symlink(Unit *u, const char* where);
const char *unit_active_state_to_string(UnitActiveState i) _const_;
UnitActiveState unit_active_state_from_string(const char *s) _pure_;
/* Macros which append UNIT= or USER_UNIT= to the message */
#define log_unit_full(unit, level, error, ...) \
({ \
Unit *_u = (unit); \
_u ? log_object_internal(level, error, __FILE__, __LINE__, __func__, _u->manager->unit_log_field, _u->id, ##__VA_ARGS__) : \
log_internal(level, error, __FILE__, __LINE__, __func__, ##__VA_ARGS__); \
})
#define log_unit_debug(unit, ...) log_unit_full(unit, LOG_DEBUG, 0, ##__VA_ARGS__)
#define log_unit_info(unit, ...) log_unit_full(unit, LOG_INFO, 0, ##__VA_ARGS__)
#define log_unit_notice(unit, ...) log_unit_full(unit, LOG_NOTICE, 0, ##__VA_ARGS__)
#define log_unit_warning(unit, ...) log_unit_full(unit, LOG_WARNING, 0, ##__VA_ARGS__)
#define log_unit_error(unit, ...) log_unit_full(unit, LOG_ERR, 0, ##__VA_ARGS__)
#define log_unit_debug_errno(unit, error, ...) log_unit_full(unit, LOG_DEBUG, error, ##__VA_ARGS__)
#define log_unit_info_errno(unit, error, ...) log_unit_full(unit, LOG_INFO, error, ##__VA_ARGS__)
#define log_unit_notice_errno(unit, error, ...) log_unit_full(unit, LOG_NOTICE, error, ##__VA_ARGS__)
#define log_unit_warning_errno(unit, error, ...) log_unit_full(unit, LOG_WARNING, error, ##__VA_ARGS__)
#define log_unit_error_errno(unit, error, ...) log_unit_full(unit, LOG_ERR, error, ##__VA_ARGS__)
#define LOG_UNIT_MESSAGE(unit, fmt, ...) "MESSAGE=%s: " fmt, (unit)->id, ##__VA_ARGS__
#define LOG_UNIT_ID(unit) (unit)->manager->unit_log_format_string, (unit)->id