src/core/unit.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 #include <stdbool.h>
   5 #include <stdlib.h>
   6 #include <unistd.h>
   7
   8 #include "bpf-program.h"
   9 #include "condition.h"
  10 #include "emergency-action.h"
  11 #include "install.h"
  12 #include "list.h"
  13 #include "unit-name.h"
  14 #include "cgroup.h"
  15
  16 typedef struct UnitRef UnitRef;
  17
  18 typedef enum KillOperation {
  19         KILL_TERMINATE,
  20         KILL_TERMINATE_AND_LOG,
  21         KILL_KILL,
  22         KILL_WATCHDOG,
  23         _KILL_OPERATION_MAX,
  24         _KILL_OPERATION_INVALID = -1
  25 } KillOperation;
  26
  27 typedef enum CollectMode {
  28         COLLECT_INACTIVE,
  29         COLLECT_INACTIVE_OR_FAILED,
  30         _COLLECT_MODE_MAX,
  31         _COLLECT_MODE_INVALID = -1,
  32 } CollectMode;
  33
  34 static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
  35         return IN_SET(t, UNIT_ACTIVE, UNIT_RELOADING);
  36 }
  37
  38 static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
  39         return IN_SET(t, UNIT_ACTIVE, UNIT_ACTIVATING, UNIT_RELOADING);
  40 }
  41
  42 static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
  43         return IN_SET(t, UNIT_INACTIVE, UNIT_FAILED, UNIT_DEACTIVATING);
  44 }
  45
  46 static inline bool UNIT_IS_INACTIVE_OR_FAILED(UnitActiveState t) {
  47         return IN_SET(t, UNIT_INACTIVE, UNIT_FAILED);
  48 }
  49
  50 /* Stores the 'reason' a dependency was created as a bit mask, i.e. due to which configuration source it came to be. We
  51  * use this so that we can selectively flush out parts of dependencies again. Note that the same dependency might be
  52  * created as a result of multiple "reasons", hence the bitmask. */
  53 typedef enum UnitDependencyMask {
  54         /* Configured directly by the unit file, .wants/.requries symlink or drop-in, or as an immediate result of a
  55          * non-dependency option configured that way.  */
  56         UNIT_DEPENDENCY_FILE               = 1 << 0,
  57
  58         /* As unconditional implicit dependency (not affected by unit configuration — except by the unit name and
  59          * type) */
  60         UNIT_DEPENDENCY_IMPLICIT           = 1 << 1,
  61
  62         /* A dependency effected by DefaultDependencies=yes. Note that dependencies marked this way are conceptually
  63          * just a subset of UNIT_DEPENDENCY_FILE, as DefaultDependencies= is itself a unit file setting that can only
  64          * be set in unit files. We make this two separate bits only to help debugging how dependencies came to be. */
  65         UNIT_DEPENDENCY_DEFAULT            = 1 << 2,
  66
  67         /* A dependency created from udev rules */
  68         UNIT_DEPENDENCY_UDEV               = 1 << 3,
  69
  70         /* A dependency created because of some unit's RequiresMountsFor= setting */
  71         UNIT_DEPENDENCY_PATH               = 1 << 4,
  72
  73         /* A dependency created because of data read from /proc/self/mountinfo and no other configuration source */
  74         UNIT_DEPENDENCY_MOUNTINFO_IMPLICIT = 1 << 5,
  75
  76         /* A dependency created because of data read from /proc/self/mountinfo, but conditionalized by
  77          * DefaultDependencies= and thus also involving configuration from UNIT_DEPENDENCY_FILE sources */
  78         UNIT_DEPENDENCY_MOUNTINFO_DEFAULT  = 1 << 6,
  79
  80         /* A dependency created because of data read from /proc/swaps and no other configuration source */
  81         UNIT_DEPENDENCY_PROC_SWAP          = 1 << 7,
  82
  83         _UNIT_DEPENDENCY_MASK_FULL         = (1 << 8) - 1,
  84 } UnitDependencyMask;
  85
  86 /* The Unit's dependencies[] hashmaps use this structure as value. It has the same size as a void pointer, and thus can
  87  * be stored directly as hashmap value, without any indirection. Note that this stores two masks, as both the origin
  88  * and the destination of a dependency might have created it. */
  89 typedef union UnitDependencyInfo {
  90         void *data;
  91         struct {
  92                 UnitDependencyMask origin_mask:16;
  93                 UnitDependencyMask destination_mask:16;
  94         } _packed_;
  95 } UnitDependencyInfo;
  96
  97 #include "job.h"
  98
  99 struct UnitRef {
 100         /* Keeps tracks of references to a unit. This is useful so
 101          * that we can merge two units if necessary and correct all
 102          * references to them */
 103
 104         Unit *source, *target;
 105         LIST_FIELDS(UnitRef, refs_by_target);
 106 };
 107
 108 typedef struct Unit {
 109         Manager *manager;
 110
 111         UnitType type;
 112         UnitLoadState load_state;
 113         Unit *merged_into;
 114
 115         char *id; /* One name is special because we use it for identification. Points to an entry in the names set */
 116         char *instance;
 117
 118         Set *names;
 119
 120         /* For each dependency type we maintain a Hashmap whose key is the Unit* object, and the value encodes why the
 121          * dependency exists, using the UnitDependencyInfo type */
 122         Hashmap *dependencies[_UNIT_DEPENDENCY_MAX];
 123
 124         /* Similar, for RequiresMountsFor= path dependencies. The key is the path, the value the UnitDependencyInfo type */
 125         Hashmap *requires_mounts_for;
 126
 127         char *description;
 128         char **documentation;
 129
 130         char *fragment_path; /* if loaded from a config file this is the primary path to it */
 131         char *source_path; /* if converted, the source file */
 132         char **dropin_paths;
 133
 134         usec_t fragment_mtime;
 135         usec_t source_mtime;
 136         usec_t dropin_mtime;
 137
 138         /* If this is a transient unit we are currently writing, this is where we are writing it to */
 139         FILE *transient_file;
 140
 141         /* If there is something to do with this unit, then this is the installed job for it */
 142         Job *job;
 143
 144         /* JOB_NOP jobs are special and can be installed without disturbing the real job. */
 145         Job *nop_job;
 146
 147         /* The slot used for watching NameOwnerChanged signals */
 148         sd_bus_slot *match_bus_slot;
 149
 150         /* References to this unit from clients */
 151         sd_bus_track *bus_track;
 152         char **deserialized_refs;
 153
 154         /* Job timeout and action to take */
 155         usec_t job_timeout;
 156         usec_t job_running_timeout;
 157         bool job_running_timeout_set:1;
 158         EmergencyAction job_timeout_action;
 159         char *job_timeout_reboot_arg;
 160
 161         /* References to this */
 162         LIST_HEAD(UnitRef, refs_by_target);
 163
 164         /* Conditions to check */
 165         LIST_HEAD(Condition, conditions);
 166         LIST_HEAD(Condition, asserts);
 167
 168         dual_timestamp condition_timestamp;
 169         dual_timestamp assert_timestamp;
 170
 171         /* Updated whenever the low-level state changes */
 172         dual_timestamp state_change_timestamp;
 173
 174         /* Updated whenever the (high-level) active state enters or leaves the active or inactive states */
 175         dual_timestamp inactive_exit_timestamp;
 176         dual_timestamp active_enter_timestamp;
 177         dual_timestamp active_exit_timestamp;
 178         dual_timestamp inactive_enter_timestamp;
 179
 180         UnitRef slice;
 181
 182         /* Per type list */
 183         LIST_FIELDS(Unit, units_by_type);
 184
 185         /* Load queue */
 186         LIST_FIELDS(Unit, load_queue);
 187
 188         /* D-Bus queue */
 189         LIST_FIELDS(Unit, dbus_queue);
 190
 191         /* Cleanup queue */
 192         LIST_FIELDS(Unit, cleanup_queue);
 193
 194         /* GC queue */
 195         LIST_FIELDS(Unit, gc_queue);
 196
 197         /* CGroup realize members queue */
 198         LIST_FIELDS(Unit, cgroup_realize_queue);
 199
 200         /* cgroup empty queue */
 201         LIST_FIELDS(Unit, cgroup_empty_queue);
 202
 203         /* cgroup OOM queue */
 204         LIST_FIELDS(Unit, cgroup_oom_queue);
 205
 206         /* Target dependencies queue */
 207         LIST_FIELDS(Unit, target_deps_queue);
 208
 209         /* Queue of units with StopWhenUnneeded set that shell be checked for clean-up. */
 210         LIST_FIELDS(Unit, stop_when_unneeded_queue);
 211
 212         /* PIDs we keep an eye on. Note that a unit might have many
 213          * more, but these are the ones we care enough about to
 214          * process SIGCHLD for */
 215         Set *pids;
 216
 217         /* Used in SIGCHLD and sd_notify() message event invocation logic to avoid that we dispatch the same event
 218          * multiple times on the same unit. */
 219         unsigned sigchldgen;
 220         unsigned notifygen;
 221
 222         /* Used during GC sweeps */
 223         unsigned gc_marker;
 224
 225         /* Error code when we didn't manage to load the unit (negative) */
 226         int load_error;
 227
 228         /* Put a ratelimit on unit starting */
 229         RateLimit start_limit;
 230         EmergencyAction start_limit_action;
 231
 232         /* What to do on failure or success */
 233         EmergencyAction success_action, failure_action;
 234         int success_action_exit_status, failure_action_exit_status;
 235         char *reboot_arg;
 236
 237         /* Make sure we never enter endless loops with the check unneeded logic, or the BindsTo= logic */
 238         RateLimit auto_stop_ratelimit;
 239
 240         /* Reference to a specific UID/GID */
 241         uid_t ref_uid;
 242         gid_t ref_gid;
 243
 244         /* Cached unit file state and preset */
 245         UnitFileState unit_file_state;
 246         int unit_file_preset;
 247
 248         /* Where the cpu.stat or cpuacct.usage was at the time the unit was started */
 249         nsec_t cpu_usage_base;
 250         nsec_t cpu_usage_last; /* the most recently read value */
 251
 252         /* The  current counter of the oom_kill field in the memory.events cgroup attribute */
 253         uint64_t oom_kill_last;
 254
 255         /* Counterparts in the cgroup filesystem */
 256         char *cgroup_path;
 257         CGroupMask cgroup_realized_mask;           /* In which hierarchies does this unit's cgroup exist? (only relevant on cgroup v1) */
 258         CGroupMask cgroup_enabled_mask;            /* Which controllers are enabled (or more correctly: enabled for the children) for this unit's cgroup? (only relevant on cgroup v2) */
 259         CGroupMask cgroup_invalidated_mask;        /* A mask specifiying controllers which shall be considered invalidated, and require re-realization */
 260         CGroupMask cgroup_members_mask;            /* A cache for the controllers required by all children of this cgroup (only relevant for slice units) */
 261
 262         /* Inotify watch descriptors for watching cgroup.events and memory.events on cgroupv2 */
 263         int cgroup_control_inotify_wd;
 264         int cgroup_memory_inotify_wd;
 265
 266         /* Device Controller BPF program */
 267         BPFProgram *bpf_device_control_installed;
 268
 269         /* IP BPF Firewalling/accounting */
 270         int ip_accounting_ingress_map_fd;
 271         int ip_accounting_egress_map_fd;
 272
 273         int ipv4_allow_map_fd;
 274         int ipv6_allow_map_fd;
 275         int ipv4_deny_map_fd;
 276         int ipv6_deny_map_fd;
 277
 278         BPFProgram *ip_bpf_ingress, *ip_bpf_ingress_installed;
 279         BPFProgram *ip_bpf_egress, *ip_bpf_egress_installed;
 280
 281         uint64_t ip_accounting_extra[_CGROUP_IP_ACCOUNTING_METRIC_MAX];
 282
 283         /* Low-priority event source which is used to remove watched PIDs that have gone away, and subscribe to any new
 284          * ones which might have appeared. */
 285         sd_event_source *rewatch_pids_event_source;
 286
 287         /* How to start OnFailure units */
 288         JobMode on_failure_job_mode;
 289
 290         /* Tweaking the GC logic */
 291         CollectMode collect_mode;
 292
 293         /* The current invocation ID */
 294         sd_id128_t invocation_id;
 295         char invocation_id_string[SD_ID128_STRING_MAX]; /* useful when logging */
 296
 297         /* Garbage collect us we nobody wants or requires us anymore */
 298         bool stop_when_unneeded;
 299
 300         /* Create default dependencies */
 301         bool default_dependencies;
 302
 303         /* Refuse manual starting, allow starting only indirectly via dependency. */
 304         bool refuse_manual_start;
 305
 306         /* Don't allow the user to stop this unit manually, allow stopping only indirectly via dependency. */
 307         bool refuse_manual_stop;
 308
 309         /* Allow isolation requests */
 310         bool allow_isolate;
 311
 312         /* Ignore this unit when isolating */
 313         bool ignore_on_isolate;
 314
 315         /* Did the last condition check succeed? */
 316         bool condition_result;
 317         bool assert_result;
 318
 319         /* Is this a transient unit? */
 320         bool transient;
 321
 322         /* Is this a unit that is always running and cannot be stopped? */
 323         bool perpetual;
 324
 325         /* Booleans indicating membership of this unit in the various queues */
 326         bool in_load_queue:1;
 327         bool in_dbus_queue:1;
 328         bool in_cleanup_queue:1;
 329         bool in_gc_queue:1;
 330         bool in_cgroup_realize_queue:1;
 331         bool in_cgroup_empty_queue:1;
 332         bool in_cgroup_oom_queue:1;
 333         bool in_target_deps_queue:1;
 334         bool in_stop_when_unneeded_queue:1;
 335
 336         bool sent_dbus_new_signal:1;
 337
 338         bool in_audit:1;
 339         bool on_console:1;
 340
 341         bool cgroup_realized:1;
 342         bool cgroup_members_mask_valid:1;
 343
 344         /* Reset cgroup accounting next time we fork something off */
 345         bool reset_accounting:1;
 346
 347         bool start_limit_hit:1;
 348
 349         /* Did we already invoke unit_coldplug() for this unit? */
 350         bool coldplugged:1;
 351
 352         /* For transient units: whether to add a bus track reference after creating the unit */
 353         bool bus_track_add:1;
 354
 355         /* Remember which unit state files we created */
 356         bool exported_invocation_id:1;
 357         bool exported_log_level_max:1;
 358         bool exported_log_extra_fields:1;
 359         bool exported_log_rate_limit_interval:1;
 360         bool exported_log_rate_limit_burst:1;
 361
 362         /* Whether we warned about clamping the CPU quota period */
 363         bool warned_clamping_cpu_quota_period:1;
 364
 365         /* When writing transient unit files, stores which section we stored last. If < 0, we didn't write any yet. If
 366          * == 0 we are in the [Unit] section, if > 0 we are in the unit type-specific section. */
 367         signed int last_section_private:2;
 368 } Unit;
 369
 370 typedef struct UnitStatusMessageFormats {
 371         const char *starting_stopping[2];
 372         const char *finished_start_job[_JOB_RESULT_MAX];
 373         const char *finished_stop_job[_JOB_RESULT_MAX];
 374 } UnitStatusMessageFormats;
 375
 376 /* Flags used when writing drop-in files or transient unit files */
 377 typedef enum UnitWriteFlags {
 378         /* Write a runtime unit file or drop-in (i.e. one below /run) */
 379         UNIT_RUNTIME           = 1 << 0,
 380
 381         /* Write a persistent drop-in (i.e. one below /etc) */
 382         UNIT_PERSISTENT        = 1 << 1,
 383
 384         /* Place this item in the per-unit-type private section, instead of [Unit] */
 385         UNIT_PRIVATE           = 1 << 2,
 386
 387         /* Apply specifier escaping before writing */
 388         UNIT_ESCAPE_SPECIFIERS = 1 << 3,
 389
 390         /* Apply C escaping before writing */
 391         UNIT_ESCAPE_C          = 1 << 4,
 392 } UnitWriteFlags;
 393
 394 /* Returns true if neither persistent, nor runtime storage is requested, i.e. this is a check invocation only */
 395 static inline bool UNIT_WRITE_FLAGS_NOOP(UnitWriteFlags flags) {
 396         return (flags & (UNIT_RUNTIME|UNIT_PERSISTENT)) == 0;
 397 }
 398
 399 #include "kill.h"
 400
 401 typedef struct UnitVTable {
 402         /* How much memory does an object of this unit type need */
 403         size_t object_size;
 404
 405         /* If greater than 0, the offset into the object where
 406          * ExecContext is found, if the unit type has that */
 407         size_t exec_context_offset;
 408
 409         /* If greater than 0, the offset into the object where
 410          * CGroupContext is found, if the unit type has that */
 411         size_t cgroup_context_offset;
 412
 413         /* If greater than 0, the offset into the object where
 414          * KillContext is found, if the unit type has that */
 415         size_t kill_context_offset;
 416
 417         /* If greater than 0, the offset into the object where the
 418          * pointer to ExecRuntime is found, if the unit type has
 419          * that */
 420         size_t exec_runtime_offset;
 421
 422         /* If greater than 0, the offset into the object where the pointer to DynamicCreds is found, if the unit type
 423          * has that. */
 424         size_t dynamic_creds_offset;
 425
 426         /* The name of the configuration file section with the private settings of this unit */
 427         const char *private_section;
 428
 429         /* Config file sections this unit type understands, separated
 430          * by NUL chars */
 431         const char *sections;
 432
 433         /* This should reset all type-specific variables. This should
 434          * not allocate memory, and is called with zero-initialized
 435          * data. It should hence only initialize variables that need
 436          * to be set != 0. */
 437         void (*init)(Unit *u);
 438
 439         /* This should free all type-specific variables. It should be
 440          * idempotent. */
 441         void (*done)(Unit *u);
 442
 443         /* Actually load data from disk. This may fail, and should set
 444          * load_state to UNIT_LOADED, UNIT_MERGED or leave it at
 445          * UNIT_STUB if no configuration could be found. */
 446         int (*load)(Unit *u);
 447
 448         /* During deserialization we only record the intended state to return to. With coldplug() we actually put the
 449          * deserialized state in effect. This is where unit_notify() should be called to start things up. Note that
 450          * this callback is invoked *before* we leave the reloading state of the manager, i.e. *before* we consider the
 451          * reloading to be complete. Thus, this callback should just restore the exact same state for any unit that was
 452          * in effect before the reload, i.e. units should not catch up with changes happened during the reload. That's
 453          * what catchup() below is for. */
 454         int (*coldplug)(Unit *u);
 455
 456         /* This is called shortly after all units' coldplug() call was invoked, and *after* the manager left the
 457          * reloading state. It's supposed to catch up with state changes due to external events we missed so far (for
 458          * example because they took place while we were reloading/reexecing) */
 459         void (*catchup)(Unit *u);
 460
 461         void (*dump)(Unit *u, FILE *f, const char *prefix);
 462
 463         int (*start)(Unit *u);
 464         int (*stop)(Unit *u);
 465         int (*reload)(Unit *u);
 466
 467         int (*kill)(Unit *u, KillWho w, int signo, sd_bus_error *error);
 468
 469         bool (*can_reload)(Unit *u);
 470
 471         /* Write all data that cannot be restored from other sources
 472          * away using unit_serialize_item() */
 473         int (*serialize)(Unit *u, FILE *f, FDSet *fds);
 474
 475         /* Restore one item from the serialization */
 476         int (*deserialize_item)(Unit *u, const char *key, const char *data, FDSet *fds);
 477
 478         /* Try to match up fds with what we need for this unit */
 479         void (*distribute_fds)(Unit *u, FDSet *fds);
 480
 481         /* Boils down the more complex internal state of this unit to
 482          * a simpler one that the engine can understand */
 483         UnitActiveState (*active_state)(Unit *u);
 484
 485         /* Returns the substate specific to this unit type as
 486          * string. This is purely information so that we can give the
 487          * user a more fine grained explanation in which actual state a
 488          * unit is in. */
 489         const char* (*sub_state_to_string)(Unit *u);
 490
 491         /* Additionally to UnitActiveState determine whether unit is to be restarted. */
 492         bool (*will_restart)(Unit *u);
 493
 494         /* Return false when there is a reason to prevent this unit from being gc'ed
 495          * even though nothing references it and it isn't active in any way. */
 496         bool (*may_gc)(Unit *u);
 497
 498         /* When the unit is not running and no job for it queued we shall release its runtime resources */
 499         void (*release_resources)(Unit *u);
 500
 501         /* Invoked on every child that died */
 502         void (*sigchld_event)(Unit *u, pid_t pid, int code, int status);
 503
 504         /* Reset failed state if we are in failed state */
 505         void (*reset_failed)(Unit *u);
 506
 507         /* Called whenever any of the cgroups this unit watches for ran empty */
 508         void (*notify_cgroup_empty)(Unit *u);
 509
 510         /* Called whenever an OOM kill event on this unit was seen */
 511         void (*notify_cgroup_oom)(Unit *u);
 512
 513         /* Called whenever a process of this unit sends us a message */
 514         void (*notify_message)(Unit *u, const struct ucred *ucred, char **tags, FDSet *fds);
 515
 516         /* Called whenever a name this Unit registered for comes or goes away. */
 517         void (*bus_name_owner_change)(Unit *u, const char *name, const char *old_owner, const char *new_owner);
 518
 519         /* Called for each property that is being set */
 520         int (*bus_set_property)(Unit *u, const char *name, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
 521
 522         /* Called after at least one property got changed to apply the necessary change */
 523         int (*bus_commit_properties)(Unit *u);
 524
 525         /* Return the unit this unit is following */
 526         Unit *(*following)(Unit *u);
 527
 528         /* Return the set of units that are following each other */
 529         int (*following_set)(Unit *u, Set **s);
 530
 531         /* Invoked each time a unit this unit is triggering changes
 532          * state or gains/loses a job */
 533         void (*trigger_notify)(Unit *u, Unit *trigger);
 534
 535         /* Called whenever CLOCK_REALTIME made a jump */
 536         void (*time_change)(Unit *u);
 537
 538         /* Called whenever /etc/localtime was modified */
 539         void (*timezone_change)(Unit *u);
 540
 541         /* Returns the next timeout of a unit */
 542         int (*get_timeout)(Unit *u, usec_t *timeout);
 543
 544         /* Returns the main PID if there is any defined, or 0. */
 545         pid_t (*main_pid)(Unit *u);
 546
 547         /* Returns the main PID if there is any defined, or 0. */
 548         pid_t (*control_pid)(Unit *u);
 549
 550         /* Returns true if the unit currently needs access to the console */
 551         bool (*needs_console)(Unit *u);
 552
 553         /* Returns the exit status to propagate in case of FailureAction=exit/SuccessAction=exit; usually returns the
 554          * exit code of the "main" process of the service or similar. */
 555         int (*exit_status)(Unit *u);
 556
 557         /* Like the enumerate() callback further down, but only enumerates the perpetual units, i.e. all units that
 558          * unconditionally exist and are always active. The main reason to keep both enumeration functions separate is
 559          * philosophical: the state of perpetual units should be put in place by coldplug(), while the state of those
 560          * discovered through regular enumeration should be put in place by catchup(), see below. */
 561         void (*enumerate_perpetual)(Manager *m);
 562
 563         /* This is called for each unit type and should be used to enumerate units already existing in the system
 564          * internally and load them. However, everything that is loaded here should still stay in inactive state. It is
 565          * the job of the catchup() call above to put the units into the discovered state. */
 566         void (*enumerate)(Manager *m);
 567
 568         /* Type specific cleanups. */
 569         void (*shutdown)(Manager *m);
 570
 571         /* If this function is set and return false all jobs for units
 572          * of this type will immediately fail. */
 573         bool (*supported)(void);
 574
 575         /* The bus vtable */
 576         const sd_bus_vtable *bus_vtable;
 577
 578         /* The strings to print in status messages */
 579         UnitStatusMessageFormats status_message_formats;
 580
 581         /* True if transient units of this type are OK */
 582         bool can_transient:1;
 583
 584         /* True if cgroup delegation is permissible */
 585         bool can_delegate:1;
 586
 587         /* True if units of this type shall be startable only once and then never again */
 588         bool once_only:1;
 589
 590         /* True if queued jobs of this type should be GC'ed if no other job needs them anymore */
 591         bool gc_jobs:1;
 592 } UnitVTable;
 593
 594 extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX];
 595
 596 static inline const UnitVTable* UNIT_VTABLE(Unit *u) {
 597         return unit_vtable[u->type];
 598 }
 599
 600 /* For casting a unit into the various unit types */
 601 #define DEFINE_CAST(UPPERCASE, MixedCase)                               \
 602         static inline MixedCase* UPPERCASE(Unit *u) {                   \
 603                 if (_unlikely_(!u || u->type != UNIT_##UPPERCASE))      \
 604                         return NULL;                                    \
 605                                                                         \
 606                 return (MixedCase*) u;                                  \
 607         }
 608
 609 /* For casting the various unit types into a unit */
 610 #define UNIT(u)                                         \
 611         ({                                              \
 612                 typeof(u) _u_ = (u);                    \
 613                 Unit *_w_ = _u_ ? &(_u_)->meta : NULL;  \
 614                 _w_;                                    \
 615         })
 616
 617 #define UNIT_HAS_EXEC_CONTEXT(u) (UNIT_VTABLE(u)->exec_context_offset > 0)
 618 #define UNIT_HAS_CGROUP_CONTEXT(u) (UNIT_VTABLE(u)->cgroup_context_offset > 0)
 619 #define UNIT_HAS_KILL_CONTEXT(u) (UNIT_VTABLE(u)->kill_context_offset > 0)
 620
 621 static inline Unit* UNIT_TRIGGER(Unit *u) {
 622         return hashmap_first_key(u->dependencies[UNIT_TRIGGERS]);
 623 }
 624
 625 Unit *unit_new(Manager *m, size_t size);
 626 void unit_free(Unit *u);
 627 DEFINE_TRIVIAL_CLEANUP_FUNC(Unit *, unit_free);
 628
 629 int unit_new_for_name(Manager *m, size_t size, const char *name, Unit **ret);
 630 int unit_add_name(Unit *u, const char *name);
 631
 632 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference, UnitDependencyMask mask);
 633 int unit_add_two_dependencies(Unit *u, UnitDependency d, UnitDependency e, Unit *other, bool add_reference, UnitDependencyMask mask);
 634
 635 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, bool add_reference, UnitDependencyMask mask);
 636 int unit_add_two_dependencies_by_name(Unit *u, UnitDependency d, UnitDependency e, const char *name, bool add_reference, UnitDependencyMask mask);
 637
 638 int unit_add_exec_dependencies(Unit *u, ExecContext *c);
 639
 640 int unit_choose_id(Unit *u, const char *name);
 641 int unit_set_description(Unit *u, const char *description);
 642
 643 bool unit_may_gc(Unit *u);
 644
 645 void unit_add_to_load_queue(Unit *u);
 646 void unit_add_to_dbus_queue(Unit *u);
 647 void unit_add_to_cleanup_queue(Unit *u);
 648 void unit_add_to_gc_queue(Unit *u);
 649 void unit_add_to_target_deps_queue(Unit *u);
 650 void unit_submit_to_stop_when_unneeded_queue(Unit *u);
 651
 652 int unit_merge(Unit *u, Unit *other);
 653 int unit_merge_by_name(Unit *u, const char *other);
 654
 655 Unit *unit_follow_merge(Unit *u) _pure_;
 656
 657 int unit_load_fragment_and_dropin(Unit *u);
 658 int unit_load_fragment_and_dropin_optional(Unit *u);
 659 int unit_load(Unit *unit);
 660
 661 int unit_set_slice(Unit *u, Unit *slice);
 662 int unit_set_default_slice(Unit *u);
 663
 664 const char *unit_description(Unit *u) _pure_;
 665
 666 bool unit_has_name(const Unit *u, const char *name);
 667
 668 UnitActiveState unit_active_state(Unit *u);
 669
 670 const char* unit_sub_state_to_string(Unit *u);
 671
 672 void unit_dump(Unit *u, FILE *f, const char *prefix);
 673
 674 bool unit_can_reload(Unit *u) _pure_;
 675 bool unit_can_start(Unit *u) _pure_;
 676 bool unit_can_stop(Unit *u) _pure_;
 677 bool unit_can_isolate(Unit *u) _pure_;
 678
 679 int unit_start(Unit *u);
 680 int unit_stop(Unit *u);
 681 int unit_reload(Unit *u);
 682
 683 int unit_kill(Unit *u, KillWho w, int signo, sd_bus_error *error);
 684 int unit_kill_common(Unit *u, KillWho who, int signo, pid_t main_pid, pid_t control_pid, sd_bus_error *error);
 685
 686 typedef enum UnitNotifyFlags {
 687         UNIT_NOTIFY_RELOAD_FAILURE    = 1 << 0,
 688         UNIT_NOTIFY_WILL_AUTO_RESTART = 1 << 1,
 689 } UnitNotifyFlags;
 690
 691 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, UnitNotifyFlags flags);
 692
 693 int unit_watch_pid(Unit *u, pid_t pid, bool exclusive);
 694 void unit_unwatch_pid(Unit *u, pid_t pid);
 695 void unit_unwatch_all_pids(Unit *u);
 696
 697 int unit_enqueue_rewatch_pids(Unit *u);
 698 void unit_dequeue_rewatch_pids(Unit *u);
 699
 700 int unit_install_bus_match(Unit *u, sd_bus *bus, const char *name);
 701 int unit_watch_bus_name(Unit *u, const char *name);
 702 void unit_unwatch_bus_name(Unit *u, const char *name);
 703
 704 bool unit_job_is_applicable(Unit *u, JobType j);
 705
 706 int set_unit_path(const char *p);
 707
 708 char *unit_dbus_path(Unit *u);
 709 char *unit_dbus_path_invocation_id(Unit *u);
 710
 711 int unit_load_related_unit(Unit *u, const char *type, Unit **_found);
 712
 713 bool unit_can_serialize(Unit *u) _pure_;
 714
 715 int unit_serialize(Unit *u, FILE *f, FDSet *fds, bool serialize_jobs);
 716 int unit_deserialize(Unit *u, FILE *f, FDSet *fds);
 717 int unit_deserialize_skip(FILE *f);
 718
 719 int unit_add_node_dependency(Unit *u, const char *what, bool wants, UnitDependency d, UnitDependencyMask mask);
 720
 721 int unit_coldplug(Unit *u);
 722 void unit_catchup(Unit *u);
 723
 724 void unit_status_printf(Unit *u, const char *status, const char *unit_status_msg_format) _printf_(3, 0);
 725
 726 bool unit_need_daemon_reload(Unit *u);
 727
 728 void unit_reset_failed(Unit *u);
 729
 730 Unit *unit_following(Unit *u);
 731 int unit_following_set(Unit *u, Set **s);
 732
 733 const char *unit_slice_name(Unit *u);
 734
 735 bool unit_stop_pending(Unit *u) _pure_;
 736 bool unit_inactive_or_pending(Unit *u) _pure_;
 737 bool unit_active_or_pending(Unit *u);
 738 bool unit_will_restart(Unit *u);
 739
 740 int unit_add_default_target_dependency(Unit *u, Unit *target);
 741
 742 void unit_start_on_failure(Unit *u);
 743 void unit_trigger_notify(Unit *u);
 744
 745 UnitFileState unit_get_unit_file_state(Unit *u);
 746 int unit_get_unit_file_preset(Unit *u);
 747
 748 Unit* unit_ref_set(UnitRef *ref, Unit *source, Unit *target);
 749 void unit_ref_unset(UnitRef *ref);
 750
 751 #define UNIT_DEREF(ref) ((ref).target)
 752 #define UNIT_ISSET(ref) (!!(ref).target)
 753
 754 int unit_patch_contexts(Unit *u);
 755
 756 ExecContext *unit_get_exec_context(Unit *u) _pure_;
 757 KillContext *unit_get_kill_context(Unit *u) _pure_;
 758 CGroupContext *unit_get_cgroup_context(Unit *u) _pure_;
 759
 760 ExecRuntime *unit_get_exec_runtime(Unit *u) _pure_;
 761
 762 int unit_setup_exec_runtime(Unit *u);
 763 int unit_setup_dynamic_creds(Unit *u);
 764
 765 char* unit_escape_setting(const char *s, UnitWriteFlags flags, char **buf);
 766 char* unit_concat_strv(char **l, UnitWriteFlags flags);
 767
 768 int unit_write_setting(Unit *u, UnitWriteFlags flags, const char *name, const char *data);
 769 int unit_write_settingf(Unit *u, UnitWriteFlags mode, const char *name, const char *format, ...) _printf_(4,5);
 770
 771 int unit_kill_context(Unit *u, KillContext *c, KillOperation k, pid_t main_pid, pid_t control_pid, bool main_pid_alien);
 772
 773 int unit_make_transient(Unit *u);
 774
 775 int unit_require_mounts_for(Unit *u, const char *path, UnitDependencyMask mask);
 776
 777 bool unit_type_supported(UnitType t);
 778
 779 bool unit_is_pristine(Unit *u);
 780
 781 bool unit_is_unneeded(Unit *u);
 782
 783 pid_t unit_control_pid(Unit *u);
 784 pid_t unit_main_pid(Unit *u);
 785
 786 static inline bool unit_supported(Unit *u) {
 787         return unit_type_supported(u->type);
 788 }
 789
 790 void unit_warn_if_dir_nonempty(Unit *u, const char* where);
 791 int unit_fail_if_noncanonical(Unit *u, const char* where);
 792
 793 int unit_test_start_limit(Unit *u);
 794
 795 void unit_unref_uid(Unit *u, bool destroy_now);
 796 int unit_ref_uid(Unit *u, uid_t uid, bool clean_ipc);
 797
 798 void unit_unref_gid(Unit *u, bool destroy_now);
 799 int unit_ref_gid(Unit *u, gid_t gid, bool clean_ipc);
 800
 801 int unit_ref_uid_gid(Unit *u, uid_t uid, gid_t gid);
 802 void unit_unref_uid_gid(Unit *u, bool destroy_now);
 803
 804 void unit_notify_user_lookup(Unit *u, uid_t uid, gid_t gid);
 805
 806 int unit_set_invocation_id(Unit *u, sd_id128_t id);
 807 int unit_acquire_invocation_id(Unit *u);
 808
 809 bool unit_shall_confirm_spawn(Unit *u);
 810
 811 int unit_set_exec_params(Unit *s, ExecParameters *p);
 812
 813 int unit_fork_helper_process(Unit *u, const char *name, pid_t *ret);
 814
 815 void unit_remove_dependencies(Unit *u, UnitDependencyMask mask);
 816
 817 void unit_export_state_files(Unit *u);
 818 void unit_unlink_state_files(Unit *u);
 819
 820 int unit_prepare_exec(Unit *u);
 821
 822 int unit_warn_leftover_processes(Unit *u);
 823
 824 bool unit_needs_console(Unit *u);
 825
 826 const char *unit_label_path(Unit *u);
 827
 828 int unit_pid_attachable(Unit *unit, pid_t pid, sd_bus_error *error);
 829
 830 void unit_log_success(Unit *u);
 831 void unit_log_failure(Unit *u, const char *result);
 832 static inline void unit_log_result(Unit *u, bool success, const char *result) {
 833         if (success)
 834                 unit_log_success(u);
 835         else
 836                 unit_log_failure(u, result);
 837 }
 838
 839 void unit_log_process_exit(Unit *u, int level, const char *kind, const char *command, int code, int status);
 840
 841 int unit_exit_status(Unit *u);
 842 int unit_success_action_exit_status(Unit *u);
 843 int unit_failure_action_exit_status(Unit *u);
 844
 845 int unit_test_trigger_loaded(Unit *u);
 846
 847 /* Macros which append UNIT= or USER_UNIT= to the message */
 848
 849 #define log_unit_full(unit, level, error, ...)                          \
 850         ({                                                              \
 851                 const Unit *_u = (unit);                                \
 852                 _u ? log_object_internal(level, error, __FILE__, __LINE__, __func__, _u->manager->unit_log_field, _u->id, _u->manager->invocation_log_field, _u->invocation_id_string, ##__VA_ARGS__) : \
 853                         log_internal(level, error, __FILE__, __LINE__, __func__, ##__VA_ARGS__); \
 854         })
 855
 856 #define log_unit_debug(unit, ...)   log_unit_full(unit, LOG_DEBUG, 0, ##__VA_ARGS__)
 857 #define log_unit_info(unit, ...)    log_unit_full(unit, LOG_INFO, 0, ##__VA_ARGS__)
 858 #define log_unit_notice(unit, ...)  log_unit_full(unit, LOG_NOTICE, 0, ##__VA_ARGS__)
 859 #define log_unit_warning(unit, ...) log_unit_full(unit, LOG_WARNING, 0, ##__VA_ARGS__)
 860 #define log_unit_error(unit, ...)   log_unit_full(unit, LOG_ERR, 0, ##__VA_ARGS__)
 861
 862 #define log_unit_debug_errno(unit, error, ...)   log_unit_full(unit, LOG_DEBUG, error, ##__VA_ARGS__)
 863 #define log_unit_info_errno(unit, error, ...)    log_unit_full(unit, LOG_INFO, error, ##__VA_ARGS__)
 864 #define log_unit_notice_errno(unit, error, ...)  log_unit_full(unit, LOG_NOTICE, error, ##__VA_ARGS__)
 865 #define log_unit_warning_errno(unit, error, ...) log_unit_full(unit, LOG_WARNING, error, ##__VA_ARGS__)
 866 #define log_unit_error_errno(unit, error, ...)   log_unit_full(unit, LOG_ERR, error, ##__VA_ARGS__)
 867
 868 #define LOG_UNIT_MESSAGE(unit, fmt, ...) "MESSAGE=%s: " fmt, (unit)->id, ##__VA_ARGS__
 869 #define LOG_UNIT_ID(unit) (unit)->manager->unit_log_format_string, (unit)->id
 870 #define LOG_UNIT_INVOCATION_ID(unit) (unit)->manager->invocation_log_format_string, (unit)->invocation_id_string
 871
 872 const char* collect_mode_to_string(CollectMode m) _const_;
 873 CollectMode collect_mode_from_string(const char *s) _pure_;