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Diffstat (limited to 'src/grp-system/libcore/unit.h')
| -rw-r--r-- | src/grp-system/libcore/unit.h | 639 |
1 files changed, 639 insertions, 0 deletions
diff --git a/src/grp-system/libcore/unit.h b/src/grp-system/libcore/unit.h new file mode 100644 index 0000000000..08a927962d --- /dev/null +++ b/src/grp-system/libcore/unit.h @@ -0,0 +1,639 @@ +#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 struct UnitRef UnitRef; +typedef struct UnitStatusMessageFormats UnitStatusMessageFormats; + +#include "condition.h" +#include "failure-action.h" +#include "install.h" +#include "list.h" +#include "unit-name.h" + +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 this is a transient unit we are currently writing, this is where we are writing it to */ + FILE *transient_file; + + /* 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; + + /* The slot used for watching NameOwnerChanged signals */ + sd_bus_slot *match_bus_slot; + + /* 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; + + /* Updated whenever the low-level state changes */ + dual_timestamp state_change_timestamp; + + /* Updated whenever the (high-level) active state enters or leaves the active or inactive states */ + 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); + + /* Units with the same CGroup netclass */ + LIST_FIELDS(Unit, cgroup_netclass); + + /* 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; + + /* Error code when we didn't manage to load the unit (negative) */ + int load_error; + + /* Put a ratelimit on unit starting */ + RateLimit start_limit; + FailureAction start_limit_action; + char *reboot_arg; + + /* Make sure we never enter endless loops with the check unneeded logic, or the BindsTo= logic */ + RateLimit auto_stop_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; + CGroupMask cgroup_realized_mask; + CGroupMask cgroup_enabled_mask; + CGroupMask cgroup_subtree_mask; + CGroupMask cgroup_members_mask; + int cgroup_inotify_wd; + + uint32_t cgroup_netclass_id; + + /* 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; + + /* 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; + + bool start_limit_hit:1; + + /* Did we already invoke unit_coldplug() for this unit? */ + bool coldplugged: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 "automount.h" +#include "busname.h" +#include "device.h" +#include "path.h" +#include "scope.h" +#include "slice.h" +#include "socket.h" +#include "swap.h" +#include "target.h" +#include "timer.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 */ + void (*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); + + /* 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); + + /* Returns the next timeout of a unit */ + int (*get_timeout)(Unit *u, usec_t *timeout); + + /* Returns the main PID if there is any defined, or 0. */ + pid_t (*main_pid)(Unit *u); + + /* Returns the main PID if there is any defined, or 0. */ + pid_t (*control_pid)(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. */ + void (*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 bus vtable */ + const sd_bus_vtable *bus_vtable; + + /* The strings to print in status messages */ + UnitStatusMessageFormats status_message_formats; + + /* 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_HAS_EXEC_CONTEXT(u) (UNIT_VTABLE(u)->exec_context_offset > 0) +#define UNIT_HAS_CGROUP_CONTEXT(u) (UNIT_VTABLE(u)->cgroup_context_offset > 0) +#define UNIT_HAS_KILL_CONTEXT(u) (UNIT_VTABLE(u)->kill_context_offset > 0) + +#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(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_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_set_slice(Unit *u, Unit *slice); +int unit_set_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); +void unit_unwatch_all_pids(Unit *u); + +void unit_tidy_watch_pids(Unit *u, pid_t except1, pid_t except2); + +int unit_install_bus_match(Unit *u, sd_bus *bus, const char *name); +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); +int unit_deserialize(Unit *u, FILE *f, FDSet *fds); + +int unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value); +int unit_serialize_item_escaped(Unit *u, FILE *f, const char *key, const char *value); +int unit_serialize_item_fd(Unit *u, FILE *f, FDSet *fds, const char *key, int fd); +void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *value, ...) _printf_(4,5); + +int unit_add_node_link(Unit *u, const char *what, bool wants, UnitDependency d); + +int unit_coldplug(Unit *u); + +void unit_status_printf(Unit *u, const char *status, const char *unit_status_msg_format) _printf_(3, 0); +void unit_status_emit_starting_stopping_reloading(Unit *u, JobType t); + +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); + +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_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); + +bool unit_is_pristine(Unit *u); + +pid_t unit_control_pid(Unit *u); +pid_t unit_main_pid(Unit *u); + +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); + +int unit_start_limit_test(Unit *u); + +/* 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 |