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+/*-*- 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