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-rw-r--r--src/core/snapshot.c309
1 files changed, 309 insertions, 0 deletions
diff --git a/src/core/snapshot.c b/src/core/snapshot.c
new file mode 100644
index 0000000000..82ec5104db
--- /dev/null
+++ b/src/core/snapshot.c
@@ -0,0 +1,309 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+
+#include "unit.h"
+#include "snapshot.h"
+#include "unit-name.h"
+#include "dbus-snapshot.h"
+#include "bus-errors.h"
+
+static const UnitActiveState state_translation_table[_SNAPSHOT_STATE_MAX] = {
+ [SNAPSHOT_DEAD] = UNIT_INACTIVE,
+ [SNAPSHOT_ACTIVE] = UNIT_ACTIVE
+};
+
+static void snapshot_init(Unit *u) {
+ Snapshot *s = SNAPSHOT(u);
+
+ assert(s);
+ assert(UNIT(s)->load_state == UNIT_STUB);
+
+ UNIT(s)->ignore_on_isolate = true;
+ UNIT(s)->ignore_on_snapshot = true;
+}
+
+static void snapshot_set_state(Snapshot *s, SnapshotState state) {
+ SnapshotState old_state;
+ assert(s);
+
+ old_state = s->state;
+ s->state = state;
+
+ if (state != old_state)
+ log_debug("%s changed %s -> %s",
+ UNIT(s)->id,
+ snapshot_state_to_string(old_state),
+ snapshot_state_to_string(state));
+
+ unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], true);
+}
+
+static int snapshot_load(Unit *u) {
+ Snapshot *s = SNAPSHOT(u);
+
+ assert(u);
+ assert(u->load_state == UNIT_STUB);
+
+ /* Make sure that only snapshots created via snapshot_create()
+ * can be loaded */
+ if (!s->by_snapshot_create && UNIT(s)->manager->n_reloading <= 0)
+ return -ENOENT;
+
+ u->load_state = UNIT_LOADED;
+ return 0;
+}
+
+static int snapshot_coldplug(Unit *u) {
+ Snapshot *s = SNAPSHOT(u);
+
+ assert(s);
+ assert(s->state == SNAPSHOT_DEAD);
+
+ if (s->deserialized_state != s->state)
+ snapshot_set_state(s, s->deserialized_state);
+
+ return 0;
+}
+
+static void snapshot_dump(Unit *u, FILE *f, const char *prefix) {
+ Snapshot *s = SNAPSHOT(u);
+
+ assert(s);
+ assert(f);
+
+ fprintf(f,
+ "%sSnapshot State: %s\n"
+ "%sClean Up: %s\n",
+ prefix, snapshot_state_to_string(s->state),
+ prefix, yes_no(s->cleanup));
+}
+
+static int snapshot_start(Unit *u) {
+ Snapshot *s = SNAPSHOT(u);
+
+ assert(s);
+ assert(s->state == SNAPSHOT_DEAD);
+
+ snapshot_set_state(s, SNAPSHOT_ACTIVE);
+
+ if (s->cleanup)
+ unit_add_to_cleanup_queue(u);
+
+ return 0;
+}
+
+static int snapshot_stop(Unit *u) {
+ Snapshot *s = SNAPSHOT(u);
+
+ assert(s);
+ assert(s->state == SNAPSHOT_ACTIVE);
+
+ snapshot_set_state(s, SNAPSHOT_DEAD);
+ return 0;
+}
+
+static int snapshot_serialize(Unit *u, FILE *f, FDSet *fds) {
+ Snapshot *s = SNAPSHOT(u);
+ Unit *other;
+ Iterator i;
+
+ assert(s);
+ assert(f);
+ assert(fds);
+
+ unit_serialize_item(u, f, "state", snapshot_state_to_string(s->state));
+ unit_serialize_item(u, f, "cleanup", yes_no(s->cleanup));
+ SET_FOREACH(other, u->dependencies[UNIT_WANTS], i)
+ unit_serialize_item(u, f, "wants", other->id);
+
+ return 0;
+}
+
+static int snapshot_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
+ Snapshot *s = SNAPSHOT(u);
+ int r;
+
+ assert(u);
+ assert(key);
+ assert(value);
+ assert(fds);
+
+ if (streq(key, "state")) {
+ SnapshotState state;
+
+ if ((state = snapshot_state_from_string(value)) < 0)
+ log_debug("Failed to parse state value %s", value);
+ else
+ s->deserialized_state = state;
+
+ } else if (streq(key, "cleanup")) {
+
+ if ((r = parse_boolean(value)) < 0)
+ log_debug("Failed to parse cleanup value %s", value);
+ else
+ s->cleanup = r;
+
+ } else if (streq(key, "wants")) {
+
+ if ((r = unit_add_two_dependencies_by_name(u, UNIT_AFTER, UNIT_WANTS, value, NULL, true)) < 0)
+ return r;
+ } else
+ log_debug("Unknown serialization key '%s'", key);
+
+ return 0;
+}
+
+static UnitActiveState snapshot_active_state(Unit *u) {
+ assert(u);
+
+ return state_translation_table[SNAPSHOT(u)->state];
+}
+
+static const char *snapshot_sub_state_to_string(Unit *u) {
+ assert(u);
+
+ return snapshot_state_to_string(SNAPSHOT(u)->state);
+}
+
+int snapshot_create(Manager *m, const char *name, bool cleanup, DBusError *e, Snapshot **_s) {
+ Iterator i;
+ Unit *other, *u = NULL;
+ char *n = NULL;
+ int r;
+ const char *k;
+
+ assert(m);
+ assert(_s);
+
+ if (name) {
+ if (!unit_name_is_valid(name, false)) {
+ dbus_set_error(e, BUS_ERROR_INVALID_NAME, "Unit name %s is not valid.", name);
+ return -EINVAL;
+ }
+
+ if (unit_name_to_type(name) != UNIT_SNAPSHOT) {
+ dbus_set_error(e, BUS_ERROR_UNIT_TYPE_MISMATCH, "Unit name %s lacks snapshot suffix.", name);
+ return -EINVAL;
+ }
+
+ if (manager_get_unit(m, name)) {
+ dbus_set_error(e, BUS_ERROR_UNIT_EXISTS, "Snapshot %s exists already.", name);
+ return -EEXIST;
+ }
+
+ } else {
+
+ for (;;) {
+ if (asprintf(&n, "snapshot-%u.snapshot", ++ m->n_snapshots) < 0)
+ return -ENOMEM;
+
+ if (!manager_get_unit(m, n))
+ break;
+
+ free(n);
+ }
+
+ name = n;
+ }
+
+ r = manager_load_unit_prepare(m, name, NULL, e, &u);
+ free(n);
+
+ if (r < 0)
+ goto fail;
+
+ SNAPSHOT(u)->by_snapshot_create = true;
+ manager_dispatch_load_queue(m);
+ assert(u->load_state == UNIT_LOADED);
+
+ HASHMAP_FOREACH_KEY(other, k, m->units, i) {
+
+ if (other->ignore_on_snapshot)
+ continue;
+
+ if (k != other->id)
+ continue;
+
+ if (UNIT_VTABLE(other)->check_snapshot)
+ if (!UNIT_VTABLE(other)->check_snapshot(other))
+ continue;
+
+ if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
+ continue;
+
+ if ((r = unit_add_two_dependencies(u, UNIT_AFTER, UNIT_WANTS, other, true)) < 0)
+ goto fail;
+ }
+
+ SNAPSHOT(u)->cleanup = cleanup;
+ *_s = SNAPSHOT(u);
+
+ return 0;
+
+fail:
+ if (u)
+ unit_add_to_cleanup_queue(u);
+
+ return r;
+}
+
+void snapshot_remove(Snapshot *s) {
+ assert(s);
+
+ unit_add_to_cleanup_queue(UNIT(s));
+}
+
+static const char* const snapshot_state_table[_SNAPSHOT_STATE_MAX] = {
+ [SNAPSHOT_DEAD] = "dead",
+ [SNAPSHOT_ACTIVE] = "active"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(snapshot_state, SnapshotState);
+
+const UnitVTable snapshot_vtable = {
+ .suffix = ".snapshot",
+ .object_size = sizeof(Snapshot),
+
+ .no_alias = true,
+ .no_instances = true,
+ .no_gc = true,
+
+ .init = snapshot_init,
+
+ .load = snapshot_load,
+ .coldplug = snapshot_coldplug,
+
+ .dump = snapshot_dump,
+
+ .start = snapshot_start,
+ .stop = snapshot_stop,
+
+ .serialize = snapshot_serialize,
+ .deserialize_item = snapshot_deserialize_item,
+
+ .active_state = snapshot_active_state,
+ .sub_state_to_string = snapshot_sub_state_to_string,
+
+ .bus_interface = "org.freedesktop.systemd1.Snapshot",
+ .bus_message_handler = bus_snapshot_message_handler
+};