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Diffstat (limited to 'src/unit.h')
| -rw-r--r-- | src/unit.h | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/src/unit.h b/src/unit.h new file mode 100644 index 0000000000..8f9d9e9860 --- /dev/null +++ b/src/unit.h @@ -0,0 +1,448 @@ +/*-*- Mode: C; c-basic-offset: 8 -*-*/ + +#ifndef foounithfoo +#define foounithfoo + +/*** + 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 General Public License as published by + the Free Software Foundation; either version 2 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 + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <stdbool.h> +#include <stdlib.h> + +typedef union Unit Unit; +typedef struct Meta Meta; +typedef struct UnitVTable UnitVTable; +typedef enum UnitType UnitType; +typedef enum UnitLoadState UnitLoadState; +typedef enum UnitActiveState UnitActiveState; +typedef enum UnitDependency UnitDependency; + +#include "set.h" +#include "util.h" +#include "list.h" +#include "socket-util.h" +#include "execute.h" + +#define UNIT_NAME_MAX 128 +#define DEFAULT_TIMEOUT_USEC (20*USEC_PER_SEC) +#define DEFAULT_RESTART_USEC (100*USEC_PER_MSEC) + +typedef enum KillMode { + KILL_CONTROL_GROUP = 0, + KILL_PROCESS_GROUP, + KILL_PROCESS, + KILL_NONE, + _KILL_MODE_MAX, + _KILL_MODE_INVALID = -1 +} KillMode; + +enum UnitType { + UNIT_SERVICE = 0, + UNIT_SOCKET, + UNIT_TARGET, + UNIT_DEVICE, + UNIT_MOUNT, + UNIT_AUTOMOUNT, + UNIT_SNAPSHOT, + UNIT_TIMER, + UNIT_SWAP, + _UNIT_TYPE_MAX, + _UNIT_TYPE_INVALID = -1 +}; + +enum UnitLoadState { + UNIT_STUB, + UNIT_LOADED, + UNIT_FAILED, + UNIT_MERGED, + _UNIT_LOAD_STATE_MAX, + _UNIT_LOAD_STATE_INVALID = -1 +}; + +enum UnitActiveState { + UNIT_ACTIVE, + UNIT_ACTIVE_RELOADING, + UNIT_INACTIVE, + UNIT_ACTIVATING, + UNIT_DEACTIVATING, + _UNIT_ACTIVE_STATE_MAX, + _UNIT_ACTIVE_STATE_INVALID = -1 +}; + +static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) { + return t == UNIT_ACTIVE || t == UNIT_ACTIVE_RELOADING; +} + +static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) { + return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_ACTIVE_RELOADING; +} + +static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) { + return t == UNIT_INACTIVE || t == UNIT_DEACTIVATING; +} + +enum UnitDependency { + /* Positive dependencies */ + UNIT_REQUIRES, + UNIT_REQUIRES_OVERRIDABLE, + UNIT_REQUISITE, + UNIT_REQUISITE_OVERRIDABLE, + UNIT_WANTS, + + /* Inverse of the above */ + UNIT_REQUIRED_BY, /* inverse of 'requires' and 'requisite' is 'required_by' */ + UNIT_REQUIRED_BY_OVERRIDABLE, /* inverse of 'soft_requires' and 'soft_requisite' is 'soft_required_by' */ + UNIT_WANTED_BY, /* inverse of 'wants' */ + + /* Negative dependencies */ + UNIT_CONFLICTS, /* inverse of 'conflicts' is 'conflicts' */ + + /* Order */ + UNIT_BEFORE, /* inverse of 'before' is 'after' and vice versa */ + UNIT_AFTER, + + /* 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" +#include "cgroup.h" + +struct Meta { + 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 *description; + char *fragment_path; /* if loaded from a config file this is the primary path to it */ + + /* If there is something to do with this unit, then this is + * the job for it */ + Job *job; + + usec_t inactive_exit_timestamp; + usec_t active_enter_timestamp; + usec_t active_exit_timestamp; + usec_t inactive_enter_timestamp; + + /* Counterparts in the cgroup filesystem */ + CGroupBonding *cgroup_bondings; + + /* Per type list */ + LIST_FIELDS(Meta, units_per_type); + + /* Load queue */ + LIST_FIELDS(Meta, load_queue); + + /* D-Bus queue */ + LIST_FIELDS(Meta, dbus_queue); + + /* Cleanup queue */ + LIST_FIELDS(Meta, cleanup_queue); + + /* GC queue */ + LIST_FIELDS(Meta, gc_queue); + + /* Used during GC sweeps */ + unsigned gc_marker; + + /* If we go down, pull down everything that depends on us, too */ + bool recursive_stop; + + /* Garbage collect us we nobody wants or requires us anymore */ + bool stop_when_unneeded; + + bool in_load_queue:1; + bool in_dbus_queue:1; + bool in_cleanup_queue:1; + bool in_gc_queue:1; + + bool sent_dbus_new_signal:1; +}; + +#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" + +union Unit { + Meta meta; + Service service; + Timer timer; + Socket socket; + Target target; + Device device; + Mount mount; + Automount automount; + Snapshot snapshot; + Swap swap; +}; + +struct UnitVTable { + const char *suffix; + + /* 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 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); + + 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); + + /* 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 finegrained 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); + + void (*fd_event)(Unit *u, int fd, uint32_t events, Watch *w); + void (*sigchld_event)(Unit *u, pid_t pid, int code, int status); + void (*timer_event)(Unit *u, uint64_t n_elapsed, Watch *w); + + /* Called whenever any of the cgroups this unit watches for + * ran empty */ + void (*cgroup_notify_empty)(Unit *u); + + /* Called whenever a name thus 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 whenever a bus PID lookup finishes */ + void (*bus_query_pid_done)(Unit *u, const char *name, pid_t pid); + + /* Called for each message received on the bus */ + DBusHandlerResult (*bus_message_handler)(Unit *u, DBusMessage *message); + + /* 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); + + /* Can units of this type have multiple names? */ + bool no_alias:1; + + /* If true units of this types can never have "Requires" + * dependencies, because state changes can only be observed, + * not triggered */ + bool no_requires:1; + + /* Instances make no sense for this type */ + bool no_instances:1; + + /* Exclude this type from snapshots */ + bool no_snapshots:1; + + /* Exclude from automatic gc */ + bool no_gc:1; + + /* Exclude from isolation requests */ + bool no_isolate:1; +}; + +extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX]; + +#define UNIT_VTABLE(u) unit_vtable[(u)->meta.type] + +/* For casting a unit into the various unit types */ +#define DEFINE_CAST(UPPERCASE, MixedCase) \ + static inline MixedCase* UPPERCASE(Unit *u) { \ + if (!u || u->meta.type != UNIT_##UPPERCASE) \ + return NULL; \ + \ + return (MixedCase*) u; \ + } + +/* For casting the various unit types into a unit */ +#define UNIT(u) ((Unit*) (u)) + +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); + +Unit *unit_new(Manager *m); +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_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *filename, 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_exec_dependencies(Unit *u, ExecContext *c); + +int unit_add_cgroup(Unit *u, CGroupBonding *b); +int unit_add_cgroup_from_text(Unit *u, const char *name); +int unit_add_default_cgroup(Unit *u); +CGroupBonding* unit_get_default_cgroup(Unit *u); + +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); + +int unit_load_fragment_and_dropin(Unit *u); +int unit_load_fragment_and_dropin_optional(Unit *u); +int unit_load_nop(Unit *u); +int unit_load(Unit *unit); + +const char *unit_description(Unit *u); + +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); +bool unit_can_start(Unit *u); + +int unit_start(Unit *u); +int unit_stop(Unit *u); +int unit_reload(Unit *u); + +void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns); + +int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w); +void unit_unwatch_fd(Unit *u, Watch *w); + +int unit_watch_pid(Unit *u, pid_t pid); +void unit_unwatch_pid(Unit *u, pid_t pid); + +int unit_watch_timer(Unit *u, usec_t delay, Watch *w); +void unit_unwatch_timer(Unit *u, Watch *w); + +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); +int unit_get_related_unit(Unit *u, const char *type, Unit **_found); + +char *unit_name_printf(Unit *u, const char* text); +char *unit_full_printf(Unit *u, const char *text); +char **unit_full_printf_strv(Unit *u, char **l); + +bool unit_can_serialize(Unit *u); +int unit_serialize(Unit *u, FILE *f, FDSet *fds); +void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *value, ...) _printf_attr(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); + +const char *unit_type_to_string(UnitType i); +UnitType unit_type_from_string(const char *s); + +const char *unit_load_state_to_string(UnitLoadState i); +UnitLoadState unit_load_state_from_string(const char *s); + +const char *unit_active_state_to_string(UnitActiveState i); +UnitActiveState unit_active_state_from_string(const char *s); + +const char *unit_dependency_to_string(UnitDependency i); +UnitDependency unit_dependency_from_string(const char *s); + +const char *kill_mode_to_string(KillMode k); +KillMode kill_mode_from_string(const char *s); + +#endif |