unit.h

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 #ifndef foounithfoo
   4 #define foounithfoo
   5
   6 #include <stdbool.h>
   7 #include <stdlib.h>
   8
   9 typedef union Unit Unit;
  10 typedef struct Meta Meta;
  11 typedef struct UnitVTable UnitVTable;
  12 typedef enum UnitType UnitType;
  13 typedef enum UnitLoadState UnitLoadState;
  14 typedef enum UnitActiveState UnitActiveState;
  15 typedef enum UnitDependency UnitDependency;
  16
  17 #include "job.h"
  18 #include "manager.h"
  19 #include "set.h"
  20 #include "util.h"
  21 #include "list.h"
  22 #include "socket-util.h"
  23 #include "execute.h"
  24 #include "util.h"
  25
  26 #define UNIT_NAME_MAX 128
  27 #define DEFAULT_TIMEOUT_USEC (20*USEC_PER_SEC)
  28 #define DEFAULT_RESTART_USEC (100*USEC_PER_MSEC)
  29
  30 enum UnitType {
  31         UNIT_SERVICE = 0,
  32         UNIT_TIMER,
  33         UNIT_SOCKET,
  34         UNIT_TARGET,
  35         UNIT_DEVICE,
  36         UNIT_MOUNT,
  37         UNIT_AUTOMOUNT,
  38         UNIT_SNAPSHOT,
  39         _UNIT_TYPE_MAX,
  40         _UNIT_TYPE_INVALID = -1,
  41 };
  42
  43 enum UnitLoadState {
  44         UNIT_STUB,
  45         UNIT_LOADED,
  46         UNIT_FAILED,
  47         _UNIT_LOAD_STATE_MAX
  48 };
  49
  50 enum UnitActiveState {
  51         UNIT_ACTIVE,
  52         UNIT_ACTIVE_RELOADING,
  53         UNIT_INACTIVE,
  54         UNIT_ACTIVATING,
  55         UNIT_DEACTIVATING,
  56         _UNIT_ACTIVE_STATE_MAX
  57 };
  58
  59 static inline bool UNIT_IS_ACTIVE_OR_RELOADING(UnitActiveState t) {
  60         return t == UNIT_ACTIVE || t == UNIT_ACTIVE_RELOADING;
  61 }
  62
  63 static inline bool UNIT_IS_ACTIVE_OR_ACTIVATING(UnitActiveState t) {
  64         return t == UNIT_ACTIVE || t == UNIT_ACTIVATING || t == UNIT_ACTIVE_RELOADING;
  65 }
  66
  67 static inline bool UNIT_IS_INACTIVE_OR_DEACTIVATING(UnitActiveState t) {
  68         return t == UNIT_INACTIVE || t == UNIT_DEACTIVATING;
  69 }
  70
  71 enum UnitDependency {
  72         /* Positive dependencies */
  73         UNIT_REQUIRES,
  74         UNIT_SOFT_REQUIRES,
  75         UNIT_WANTS,
  76         UNIT_REQUISITE,
  77         UNIT_SOFT_REQUISITE,
  78
  79         /* Inverse of the above */
  80         UNIT_REQUIRED_BY,       /* inverse of 'requires' and 'requisite' is 'required_by' */
  81         UNIT_SOFT_REQUIRED_BY,  /* inverse of 'soft_requires' and 'soft_requisite' is 'soft_required_by' */
  82         UNIT_WANTED_BY,         /* inverse of 'wants' */
  83
  84         /* Negative dependencies */
  85         UNIT_CONFLICTS,         /* inverse of 'conflicts' is 'conflicts' */
  86
  87         /* Order */
  88         UNIT_BEFORE,            /* inverse of before is after and vice versa */
  89         UNIT_AFTER,
  90
  91         _UNIT_DEPENDENCY_MAX,
  92         _UNIT_DEPENDENCY_INVALID = -1
  93 };
  94
  95 struct Meta {
  96         Manager *manager;
  97         UnitType type;
  98         UnitLoadState load_state;
  99
 100         char *id; /* One name is special because we use it for identification. Points to an entry in the names set */
 101
 102         Set *names;
 103         Set *dependencies[_UNIT_DEPENDENCY_MAX];
 104
 105         char *description;
 106         char *load_path; /* if loaded from a config file this is the primary path to it */
 107
 108         /* If there is something to do with this unit, then this is
 109          * the job for it */
 110         Job *job;
 111
 112         bool in_load_queue:1;
 113
 114         usec_t active_enter_timestamp;
 115         usec_t active_exit_timestamp;
 116
 117         /* Load queue */
 118         LIST_FIELDS(Meta, load_queue);
 119 };
 120
 121 #include "service.h"
 122 #include "timer.h"
 123 #include "socket.h"
 124 #include "target.h"
 125 #include "device.h"
 126 #include "mount.h"
 127 #include "automount.h"
 128 #include "snapshot.h"
 129
 130 union Unit {
 131         Meta meta;
 132         Service service;
 133         Timer timer;
 134         Socket socket;
 135         Target target;
 136         Device device;
 137         Mount mount;
 138         Automount automount;
 139         Snapshot snapshot;
 140 };
 141
 142 struct UnitVTable {
 143         const char *suffix;
 144
 145         int (*init)(Unit *u);
 146         void (*done)(Unit *u);
 147
 148         void (*dump)(Unit *u, FILE *f, const char *prefix);
 149
 150         int (*start)(Unit *u);
 151         int (*stop)(Unit *u);
 152         int (*reload)(Unit *u);
 153
 154         bool (*can_reload)(Unit *u);
 155
 156         /* Boils down the more complex internal state of this unit to
 157          * a simpler one that the engine can understand */
 158         UnitActiveState (*active_state)(Unit *u);
 159
 160         void (*fd_event)(Unit *u, int fd, uint32_t events, Watch *w);
 161         void (*sigchld_event)(Unit *u, pid_t pid, int code, int status);
 162         void (*timer_event)(Unit *u, uint64_t n_elapsed, Watch *w);
 163 };
 164
 165 extern const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX];
 166
 167 #define UNIT_VTABLE(u) unit_vtable[(u)->meta.type]
 168
 169 /* For casting a unit into the various unit types */
 170 #define DEFINE_CAST(UPPERCASE, MixedCase)                               \
 171         static inline MixedCase* UPPERCASE(Unit *u) {                   \
 172                 if (!u || u->meta.type != UNIT_##UPPERCASE)             \
 173                         return NULL;                                    \
 174                                                                         \
 175                 return (MixedCase*) u;                                  \
 176         }
 177
 178 /* For casting the various unit types into a unit */
 179 #define UNIT(u) ((Unit*) (u))
 180
 181 DEFINE_CAST(SOCKET, Socket);
 182 DEFINE_CAST(TIMER, Timer);
 183 DEFINE_CAST(SERVICE, Service);
 184 DEFINE_CAST(TARGET, Target);
 185 DEFINE_CAST(DEVICE, Device);
 186 DEFINE_CAST(MOUNT, Mount);
 187 DEFINE_CAST(AUTOMOUNT, Automount);
 188 DEFINE_CAST(SNAPSHOT, Snapshot);
 189
 190 UnitType unit_name_to_type(const char *n);
 191 bool unit_name_is_valid(const char *n);
 192 char *unit_name_change_suffix(const char *n, const char *suffix);
 193
 194 Unit *unit_new(Manager *m);
 195 void unit_free(Unit *u);
 196
 197 int unit_add_name(Unit *u, const char *name);
 198 int unit_add_dependency(Unit *u, UnitDependency d, Unit *other);
 199 int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name);
 200
 201 void unit_add_to_load_queue(Unit *u);
 202
 203 int unit_merge(Unit *u, Unit *other);
 204
 205 int unit_load_fragment_and_dropin(Unit *u);
 206 int unit_load(Unit *unit);
 207
 208 const char* unit_id(Unit *u);
 209 const char *unit_description(Unit *u);
 210
 211 UnitActiveState unit_active_state(Unit *u);
 212
 213 void unit_dump(Unit *u, FILE *f, const char *prefix);
 214
 215 bool unit_can_reload(Unit *u);
 216 bool unit_can_start(Unit *u);
 217
 218 int unit_start(Unit *u);
 219 int unit_stop(Unit *u);
 220 int unit_reload(Unit *u);
 221
 222 void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns);
 223
 224 int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w);
 225 void unit_unwatch_fd(Unit *u, Watch *w);
 226
 227 int unit_watch_pid(Unit *u, pid_t pid);
 228 void unit_unwatch_pid(Unit *u, pid_t pid);
 229
 230 int unit_watch_timer(Unit *u, usec_t delay, Watch *w);
 231 void unit_unwatch_timer(Unit *u, Watch *w);
 232
 233 bool unit_job_is_applicable(Unit *u, JobType j);
 234
 235 const char *unit_path(void);
 236 int set_unit_path(const char *p);
 237
 238
 239 #endif