target.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <errno.h>
  23 #include <signal.h>
  24
  25 #include "unit.h"
  26 #include "target.h"
  27 #include "load-fragment.h"
  28 #include "log.h"
  29 #include "dbus-target.h"
  30
  31 static const UnitActiveState state_translation_table[_TARGET_STATE_MAX] = {
  32         [TARGET_DEAD] = UNIT_INACTIVE,
  33         [TARGET_ACTIVE] = UNIT_ACTIVE
  34 };
  35
  36 static void target_set_state(Target *t, TargetState state) {
  37         TargetState old_state;
  38         assert(t);
  39
  40         old_state = t->state;
  41         t->state = state;
  42
  43         if (state != old_state)
  44                 log_debug("%s changed %s -> %s",
  45                           UNIT(t)->meta.id,
  46                           target_state_to_string(old_state),
  47                           target_state_to_string(state));
  48
  49         unit_notify(UNIT(t), state_translation_table[old_state], state_translation_table[state]);
  50 }
  51
  52 static int target_coldplug(Unit *u) {
  53         Target *t = TARGET(u);
  54
  55         assert(t);
  56         assert(t->state == TARGET_DEAD);
  57
  58         if (t->deserialized_state != t->state)
  59                 target_set_state(t, t->deserialized_state);
  60
  61         return 0;
  62 }
  63
  64 static void target_dump(Unit *u, FILE *f, const char *prefix) {
  65         Target *t = TARGET(u);
  66
  67         assert(t);
  68         assert(f);
  69
  70         fprintf(f,
  71                 "%sTarget State: %s\n",
  72                 prefix, target_state_to_string(t->state));
  73 }
  74
  75 static int target_start(Unit *u) {
  76         Target *t = TARGET(u);
  77
  78         assert(t);
  79         assert(t->state == TARGET_DEAD);
  80
  81         target_set_state(t, TARGET_ACTIVE);
  82         return 0;
  83 }
  84
  85 static int target_stop(Unit *u) {
  86         Target *t = TARGET(u);
  87
  88         assert(t);
  89         assert(t->state == TARGET_ACTIVE);
  90
  91         target_set_state(t, TARGET_DEAD);
  92         return 0;
  93 }
  94
  95 static int target_serialize(Unit *u, FILE *f, FDSet *fds) {
  96         Target *s = TARGET(u);
  97
  98         assert(s);
  99         assert(f);
 100         assert(fds);
 101
 102         unit_serialize_item(u, f, "state", target_state_to_string(s->state));
 103         return 0;
 104 }
 105
 106 static int target_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
 107         Target *s = TARGET(u);
 108
 109         assert(u);
 110         assert(key);
 111         assert(value);
 112         assert(fds);
 113
 114         if (streq(key, "state")) {
 115                 TargetState state;
 116
 117                 if ((state = target_state_from_string(value)) < 0)
 118                         log_debug("Failed to parse state value %s", value);
 119                 else
 120                         s->deserialized_state = state;
 121
 122         } else
 123                 log_debug("Unknown serialization key '%s'", key);
 124
 125         return 0;
 126 }
 127
 128 static UnitActiveState target_active_state(Unit *u) {
 129         assert(u);
 130
 131         return state_translation_table[TARGET(u)->state];
 132 }
 133
 134 static const char *target_sub_state_to_string(Unit *u) {
 135         assert(u);
 136
 137         return target_state_to_string(TARGET(u)->state);
 138 }
 139
 140 int target_get_runlevel(Target *t) {
 141
 142         static const struct {
 143                 const char *special;
 144                 const int runlevel;
 145         } table[] = {
 146                 { SPECIAL_RUNLEVEL5_TARGET, '5' },
 147                 { SPECIAL_RUNLEVEL4_TARGET, '4' },
 148                 { SPECIAL_RUNLEVEL3_TARGET, '3' },
 149                 { SPECIAL_RUNLEVEL2_TARGET, '2' },
 150                 { SPECIAL_RUNLEVEL1_TARGET, '1' },
 151                 { SPECIAL_RUNLEVEL0_TARGET, '0' },
 152                 { SPECIAL_RUNLEVEL6_TARGET, '6' },
 153         };
 154
 155         unsigned i;
 156
 157         assert(t);
 158
 159         /* Tries to determine if this is a SysV runlevel and returns
 160          * it if that is so. */
 161
 162         for (i = 0; i < ELEMENTSOF(table); i++)
 163                 if (unit_has_name(UNIT(t), table[i].special))
 164                         return table[i].runlevel;
 165
 166         return 0;
 167 }
 168
 169 static const char* const target_state_table[_TARGET_STATE_MAX] = {
 170         [TARGET_DEAD] = "dead",
 171         [TARGET_ACTIVE] = "active"
 172 };
 173
 174 DEFINE_STRING_TABLE_LOOKUP(target_state, TargetState);
 175
 176 const UnitVTable target_vtable = {
 177         .suffix = ".target",
 178
 179         .load = unit_load_fragment_and_dropin,
 180         .coldplug = target_coldplug,
 181
 182         .dump = target_dump,
 183
 184         .start = target_start,
 185         .stop = target_stop,
 186
 187         .serialize = target_serialize,
 188         .deserialize_item = target_deserialize_item,
 189
 190         .active_state = target_active_state,
 191         .sub_state_to_string = target_sub_state_to_string,
 192
 193         .bus_message_handler = bus_target_message_handler
 194 };