summaryrefslogtreecommitdiff
path: root/src/core/target.c
blob: 6225df5b0d4d8d3a5e3df748a0d992d556787b31 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include "dbus-target.h"
#include "dbus-unit.h"
#include "log.h"
#include "serialize.h"
#include "special.h"
#include "string-util.h"
#include "target.h"
#include "unit-name.h"
#include "unit.h"

static const UnitActiveState state_translation_table[_TARGET_STATE_MAX] = {
        [TARGET_DEAD] = UNIT_INACTIVE,
        [TARGET_ACTIVE] = UNIT_ACTIVE
};

static void target_set_state(Target *t, TargetState state) {
        TargetState old_state;
        assert(t);

        if (t->state != state)
                bus_unit_send_pending_change_signal(UNIT(t), false);

        old_state = t->state;
        t->state = state;

        if (state != old_state)
                log_debug("%s changed %s -> %s",
                          UNIT(t)->id,
                          target_state_to_string(old_state),
                          target_state_to_string(state));

        unit_notify(UNIT(t), state_translation_table[old_state], state_translation_table[state], 0);
}

static int target_add_default_dependencies(Target *t) {
        _cleanup_free_ Unit **others = NULL;
        int r, n_others;

        assert(t);

        if (!UNIT(t)->default_dependencies)
                return 0;

        /* Imply ordering for requirement dependencies on target units. Note that when the user created a
         * contradicting ordering manually we won't add anything in here to make sure we don't create a
         * loop.
         *
         * Note that quite likely iterating through these dependencies will add new dependencies, which
         * conflicts with the hashmap-based iteration logic. Hence, instead of iterating through the
         * dependencies and acting on them as we go, first take an "atomic snapshot" of sorts and iterate
         * through that. */

        n_others = unit_get_dependency_array(UNIT(t), UNIT_ATOM_ADD_DEFAULT_TARGET_DEPENDENCY_QUEUE, &others);
        if (n_others < 0)
                return n_others;

        for (int i = 0; i < n_others; i++) {
                r = unit_add_default_target_dependency(others[i], UNIT(t));
                if (r < 0)
                        return r;
        }

        if (unit_has_name(UNIT(t), SPECIAL_SHUTDOWN_TARGET))
                return 0;

        /* Make sure targets are unloaded on shutdown */
        return unit_add_two_dependencies_by_name(UNIT(t), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
}

static int target_load(Unit *u) {
        Target *t = TARGET(u);
        int r;

        assert(t);

        r = unit_load_fragment_and_dropin(u, true);
        if (r < 0)
                return r;

        if (u->load_state != UNIT_LOADED)
                return 0;

        /* This is a new unit? Then let's add in some extras */
        return target_add_default_dependencies(t);
}

static int target_coldplug(Unit *u) {
        Target *t = TARGET(u);

        assert(t);
        assert(t->state == TARGET_DEAD);

        if (t->deserialized_state != t->state)
                target_set_state(t, t->deserialized_state);

        return 0;
}

static void target_dump(Unit *u, FILE *f, const char *prefix) {
        Target *t = TARGET(u);

        assert(t);
        assert(f);

        fprintf(f,
                "%sTarget State: %s\n",
                prefix, target_state_to_string(t->state));
}

static int target_start(Unit *u) {
        Target *t = TARGET(u);
        int r;

        assert(t);
        assert(t->state == TARGET_DEAD);

        r = unit_acquire_invocation_id(u);
        if (r < 0)
                return r;

        target_set_state(t, TARGET_ACTIVE);
        return 1;
}

static int target_stop(Unit *u) {
        Target *t = TARGET(u);

        assert(t);
        assert(t->state == TARGET_ACTIVE);

        target_set_state(t, TARGET_DEAD);
        return 1;
}

static int target_serialize(Unit *u, FILE *f, FDSet *fds) {
        Target *s = TARGET(u);

        assert(s);
        assert(f);
        assert(fds);

        (void) serialize_item(f, "state", target_state_to_string(s->state));
        return 0;
}

static int target_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
        Target *s = TARGET(u);

        assert(s);
        assert(u);
        assert(key);
        assert(value);
        assert(fds);

        if (streq(key, "state")) {
                TargetState state;

                state = target_state_from_string(value);
                if (state < 0)
                        log_debug("Failed to parse state value %s", value);
                else
                        s->deserialized_state = state;

        } else
                log_debug("Unknown serialization key '%s'", key);

        return 0;
}

_pure_ static UnitActiveState target_active_state(Unit *u) {
        assert(u);

        return state_translation_table[TARGET(u)->state];
}

_pure_ static const char *target_sub_state_to_string(Unit *u) {
        assert(u);

        return target_state_to_string(TARGET(u)->state);
}

const UnitVTable target_vtable = {
        .object_size = sizeof(Target),

        .sections =
                "Unit\0"
                "Target\0"
                "Install\0",

        .can_fail = true,

        .load = target_load,
        .coldplug = target_coldplug,

        .dump = target_dump,

        .start = target_start,
        .stop = target_stop,

        .serialize = target_serialize,
        .deserialize_item = target_deserialize_item,

        .active_state = target_active_state,
        .sub_state_to_string = target_sub_state_to_string,

        .status_message_formats = {
                .finished_start_job = {
                        [JOB_DONE]       = "Reached target %s.",
                },
                .finished_stop_job = {
                        [JOB_DONE]       = "Stopped target %s.",
                },
        },
};