src/core/target.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include "dbus-target.h"
   4 #include "log.h"
   5 #include "special.h"
   6 #include "string-util.h"
   7 #include "unit-name.h"
   8 #include "unit.h"
   9 #include "target.h"
  10
  11 static const UnitActiveState state_translation_table[_TARGET_STATE_MAX] = {
  12         [TARGET_DEAD] = UNIT_INACTIVE,
  13         [TARGET_ACTIVE] = UNIT_ACTIVE
  14 };
  15
  16 static void target_set_state(Target *t, TargetState state) {
  17         TargetState old_state;
  18         assert(t);
  19
  20         old_state = t->state;
  21         t->state = state;
  22
  23         if (state != old_state)
  24                 log_debug("%s changed %s -> %s",
  25                           UNIT(t)->id,
  26                           target_state_to_string(old_state),
  27                           target_state_to_string(state));
  28
  29         unit_notify(UNIT(t), state_translation_table[old_state], state_translation_table[state], 0);
  30 }
  31
  32 static int target_add_default_dependencies(Target *t) {
  33
  34         static const UnitDependency deps[] = {
  35                 UNIT_REQUIRES,
  36                 UNIT_REQUISITE,
  37                 UNIT_WANTS,
  38                 UNIT_BINDS_TO,
  39                 UNIT_PART_OF
  40         };
  41
  42         int r;
  43         unsigned k;
  44
  45         assert(t);
  46
  47         if (!UNIT(t)->default_dependencies)
  48                 return 0;
  49
  50         /* Imply ordering for requirement dependencies on target units. Note that when the user created a contradicting
  51          * ordering manually we won't add anything in here to make sure we don't create a loop. */
  52
  53         for (k = 0; k < ELEMENTSOF(deps); k++) {
  54                 Unit *other;
  55                 Iterator i;
  56                 void *v;
  57
  58                 HASHMAP_FOREACH_KEY(v, other, UNIT(t)->dependencies[deps[k]], i) {
  59                         r = unit_add_default_target_dependency(other, UNIT(t));
  60                         if (r < 0)
  61                                 return r;
  62                 }
  63         }
  64
  65         if (unit_has_name(UNIT(t), SPECIAL_SHUTDOWN_TARGET))
  66                 return 0;
  67
  68         /* Make sure targets are unloaded on shutdown */
  69         return unit_add_two_dependencies_by_name(UNIT(t), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true, UNIT_DEPENDENCY_DEFAULT);
  70 }
  71
  72 static int target_load(Unit *u) {
  73         Target *t = TARGET(u);
  74         int r;
  75
  76         assert(t);
  77
  78         r = unit_load_fragment_and_dropin(u);
  79         if (r < 0)
  80                 return r;
  81
  82         /* This is a new unit? Then let's add in some extras */
  83         if (u->load_state == UNIT_LOADED) {
  84                 r = target_add_default_dependencies(t);
  85                 if (r < 0)
  86                         return r;
  87         }
  88
  89         return 0;
  90 }
  91
  92 static int target_coldplug(Unit *u) {
  93         Target *t = TARGET(u);
  94
  95         assert(t);
  96         assert(t->state == TARGET_DEAD);
  97
  98         if (t->deserialized_state != t->state)
  99                 target_set_state(t, t->deserialized_state);
 100
 101         return 0;
 102 }
 103
 104 static void target_dump(Unit *u, FILE *f, const char *prefix) {
 105         Target *t = TARGET(u);
 106
 107         assert(t);
 108         assert(f);
 109
 110         fprintf(f,
 111                 "%sTarget State: %s\n",
 112                 prefix, target_state_to_string(t->state));
 113 }
 114
 115 static int target_start(Unit *u) {
 116         Target *t = TARGET(u);
 117         int r;
 118
 119         assert(t);
 120         assert(t->state == TARGET_DEAD);
 121
 122         r = unit_acquire_invocation_id(u);
 123         if (r < 0)
 124                 return r;
 125
 126         target_set_state(t, TARGET_ACTIVE);
 127         return 1;
 128 }
 129
 130 static int target_stop(Unit *u) {
 131         Target *t = TARGET(u);
 132
 133         assert(t);
 134         assert(t->state == TARGET_ACTIVE);
 135
 136         target_set_state(t, TARGET_DEAD);
 137         return 1;
 138 }
 139
 140 static int target_serialize(Unit *u, FILE *f, FDSet *fds) {
 141         Target *s = TARGET(u);
 142
 143         assert(s);
 144         assert(f);
 145         assert(fds);
 146
 147         unit_serialize_item(u, f, "state", target_state_to_string(s->state));
 148         return 0;
 149 }
 150
 151 static int target_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
 152         Target *s = TARGET(u);
 153
 154         assert(u);
 155         assert(key);
 156         assert(value);
 157         assert(fds);
 158
 159         if (streq(key, "state")) {
 160                 TargetState state;
 161
 162                 state = target_state_from_string(value);
 163                 if (state < 0)
 164                         log_debug("Failed to parse state value %s", value);
 165                 else
 166                         s->deserialized_state = state;
 167
 168         } else
 169                 log_debug("Unknown serialization key '%s'", key);
 170
 171         return 0;
 172 }
 173
 174 _pure_ static UnitActiveState target_active_state(Unit *u) {
 175         assert(u);
 176
 177         return state_translation_table[TARGET(u)->state];
 178 }
 179
 180 _pure_ static const char *target_sub_state_to_string(Unit *u) {
 181         assert(u);
 182
 183         return target_state_to_string(TARGET(u)->state);
 184 }
 185
 186 const UnitVTable target_vtable = {
 187         .object_size = sizeof(Target),
 188
 189         .sections =
 190                 "Unit\0"
 191                 "Target\0"
 192                 "Install\0",
 193
 194         .load = target_load,
 195         .coldplug = target_coldplug,
 196
 197         .dump = target_dump,
 198
 199         .start = target_start,
 200         .stop = target_stop,
 201
 202         .serialize = target_serialize,
 203         .deserialize_item = target_deserialize_item,
 204
 205         .active_state = target_active_state,
 206         .sub_state_to_string = target_sub_state_to_string,
 207
 208         .bus_vtable = bus_target_vtable,
 209
 210         .status_message_formats = {
 211                 .finished_start_job = {
 212                         [JOB_DONE]       = "Reached target %s.",
 213                 },
 214                 .finished_stop_job = {
 215                         [JOB_DONE]       = "Stopped target %s.",
 216                 },
 217         },
 218 };