build-sys: move source files to subdirectory

1 files changed, 1949 insertions, 0 deletions

diff --git a/src/unit.c b/src/unit.c
new file mode 100644
index 0000000000..1959b1b940
--- /dev/null
+++ b/src/unit.c
@@ -0,0 +1,1949 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+  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 <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/epoll.h>
+#include <sys/timerfd.h>
+#include <sys/poll.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "set.h"
+#include "unit.h"
+#include "macro.h"
+#include "strv.h"
+#include "load-fragment.h"
+#include "load-dropin.h"
+#include "log.h"
+#include "unit-name.h"
+#include "specifier.h"
+#include "dbus-unit.h"
+
+const UnitVTable * const unit_vtable[_UNIT_TYPE_MAX] = {
+        [UNIT_SERVICE] = &service_vtable,
+        [UNIT_TIMER] = &timer_vtable,
+        [UNIT_SOCKET] = &socket_vtable,
+        [UNIT_TARGET] = &target_vtable,
+        [UNIT_DEVICE] = &device_vtable,
+        [UNIT_MOUNT] = &mount_vtable,
+        [UNIT_AUTOMOUNT] = &automount_vtable,
+        [UNIT_SNAPSHOT] = &snapshot_vtable,
+        [UNIT_SWAP] = &swap_vtable
+};
+
+Unit *unit_new(Manager *m) {
+        Unit *u;
+
+        assert(m);
+
+        if (!(u = new0(Unit, 1)))
+                return NULL;
+
+        if (!(u->meta.names = set_new(string_hash_func, string_compare_func))) {
+                free(u);
+                return NULL;
+        }
+
+        u->meta.manager = m;
+        u->meta.type = _UNIT_TYPE_INVALID;
+
+        return u;
+}
+
+bool unit_has_name(Unit *u, const char *name) {
+        assert(u);
+        assert(name);
+
+        return !!set_get(u->meta.names, (char*) name);
+}
+
+int unit_add_name(Unit *u, const char *text) {
+        UnitType t;
+        char *s = NULL, *i = NULL;
+        int r;
+
+        assert(u);
+        assert(text);
+
+        if (unit_name_is_template(text)) {
+                if (!u->meta.instance)
+                        return -EINVAL;
+
+                s = unit_name_replace_instance(text, u->meta.instance);
+        } else
+                s = strdup(text);
+
+        if (!s)
+                return -ENOMEM;
+
+        if (!unit_name_is_valid(s)) {
+                r = -EINVAL;
+                goto fail;
+        }
+
+        assert_se((t = unit_name_to_type(s)) >= 0);
+
+        if (u->meta.type != _UNIT_TYPE_INVALID && t != u->meta.type) {
+                r = -EINVAL;
+                goto fail;
+        }
+
+        if ((r = unit_name_to_instance(s, &i)) < 0)
+                goto fail;
+
+        if (i && unit_vtable[t]->no_instances)
+                goto fail;
+
+        if (u->meta.type != _UNIT_TYPE_INVALID && !streq_ptr(u->meta.instance, i)) {
+                r = -EINVAL;
+                goto fail;
+        }
+
+        if (unit_vtable[t]->no_alias &&
+            !set_isempty(u->meta.names) &&
+            !set_get(u->meta.names, s)) {
+                r = -EEXIST;
+                goto fail;
+        }
+
+        if (hashmap_size(u->meta.manager->units) >= MANAGER_MAX_NAMES) {
+                r = -E2BIG;
+                goto fail;
+        }
+
+        if ((r = set_put(u->meta.names, s)) < 0) {
+                if (r == -EEXIST)
+                        r = 0;
+                goto fail;
+        }
+
+        if ((r = hashmap_put(u->meta.manager->units, s, u)) < 0) {
+                set_remove(u->meta.names, s);
+                goto fail;
+        }
+
+        if (u->meta.type == _UNIT_TYPE_INVALID) {
+
+                u->meta.type = t;
+                u->meta.id = s;
+                u->meta.instance = i;
+
+                LIST_PREPEND(Meta, units_per_type, u->meta.manager->units_per_type[t], &u->meta);
+
+                if (UNIT_VTABLE(u)->init)
+                        UNIT_VTABLE(u)->init(u);
+        } else
+                free(i);
+
+        unit_add_to_dbus_queue(u);
+        return 0;
+
+fail:
+        free(s);
+        free(i);
+
+        return r;
+}
+
+int unit_choose_id(Unit *u, const char *name) {
+        char *s, *t = NULL;
+
+        assert(u);
+        assert(name);
+
+        if (unit_name_is_template(name)) {
+
+                if (!u->meta.instance)
+                        return -EINVAL;
+
+                if (!(t = unit_name_replace_instance(name, u->meta.instance)))
+                        return -ENOMEM;
+
+                name = t;
+        }
+
+        /* Selects one of the names of this unit as the id */
+        s = set_get(u->meta.names, (char*) name);
+        free(t);
+
+        if (!s)
+                return -ENOENT;
+
+        u->meta.id = s;
+        unit_add_to_dbus_queue(u);
+
+        return 0;
+}
+
+int unit_set_description(Unit *u, const char *description) {
+        char *s;
+
+        assert(u);
+
+        if (!(s = strdup(description)))
+                return -ENOMEM;
+
+        free(u->meta.description);
+        u->meta.description = s;
+
+        unit_add_to_dbus_queue(u);
+        return 0;
+}
+
+bool unit_check_gc(Unit *u) {
+        assert(u);
+
+        if (UNIT_VTABLE(u)->no_gc)
+                return true;
+
+        if (u->meta.job)
+                return true;
+
+        if (unit_active_state(u) != UNIT_INACTIVE)
+                return true;
+
+        if (UNIT_VTABLE(u)->check_gc)
+                if (UNIT_VTABLE(u)->check_gc(u))
+                        return true;
+
+        return false;
+}
+
+void unit_add_to_load_queue(Unit *u) {
+        assert(u);
+        assert(u->meta.type != _UNIT_TYPE_INVALID);
+
+        if (u->meta.load_state != UNIT_STUB || u->meta.in_load_queue)
+                return;
+
+        LIST_PREPEND(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
+        u->meta.in_load_queue = true;
+}
+
+void unit_add_to_cleanup_queue(Unit *u) {
+        assert(u);
+
+        if (u->meta.in_cleanup_queue)
+                return;
+
+        LIST_PREPEND(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
+        u->meta.in_cleanup_queue = true;
+}
+
+void unit_add_to_gc_queue(Unit *u) {
+        assert(u);
+
+        if (u->meta.in_gc_queue || u->meta.in_cleanup_queue)
+                return;
+
+        if (unit_check_gc(u))
+                return;
+
+        LIST_PREPEND(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
+        u->meta.in_gc_queue = true;
+
+        u->meta.manager->n_in_gc_queue ++;
+
+        if (u->meta.manager->gc_queue_timestamp <= 0)
+                u->meta.manager->gc_queue_timestamp = now(CLOCK_MONOTONIC);
+}
+
+void unit_add_to_dbus_queue(Unit *u) {
+        assert(u);
+        assert(u->meta.type != _UNIT_TYPE_INVALID);
+
+        if (u->meta.load_state == UNIT_STUB || u->meta.in_dbus_queue)
+                return;
+
+        if (set_isempty(u->meta.manager->subscribed)) {
+                u->meta.sent_dbus_new_signal = true;
+                return;
+        }
+
+        LIST_PREPEND(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
+        u->meta.in_dbus_queue = true;
+}
+
+static void bidi_set_free(Unit *u, Set *s) {
+        Iterator i;
+        Unit *other;
+
+        assert(u);
+
+        /* Frees the set and makes sure we are dropped from the
+         * inverse pointers */
+
+        SET_FOREACH(other, s, i) {
+                UnitDependency d;
+
+                for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
+                        set_remove(other->meta.dependencies[d], u);
+
+                unit_add_to_gc_queue(other);
+        }
+
+        set_free(s);
+}
+
+void unit_free(Unit *u) {
+        UnitDependency d;
+        Iterator i;
+        char *t;
+
+        assert(u);
+
+        bus_unit_send_removed_signal(u);
+
+        /* Detach from next 'bigger' objects */
+        SET_FOREACH(t, u->meta.names, i)
+                hashmap_remove_value(u->meta.manager->units, t, u);
+
+        if (u->meta.type != _UNIT_TYPE_INVALID)
+                LIST_REMOVE(Meta, units_per_type, u->meta.manager->units_per_type[u->meta.type], &u->meta);
+
+        if (u->meta.in_load_queue)
+                LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
+
+        if (u->meta.in_dbus_queue)
+                LIST_REMOVE(Meta, dbus_queue, u->meta.manager->dbus_unit_queue, &u->meta);
+
+        if (u->meta.in_cleanup_queue)
+                LIST_REMOVE(Meta, cleanup_queue, u->meta.manager->cleanup_queue, &u->meta);
+
+        if (u->meta.in_gc_queue) {
+                LIST_REMOVE(Meta, gc_queue, u->meta.manager->gc_queue, &u->meta);
+                u->meta.manager->n_in_gc_queue--;
+        }
+
+        /* Free data and next 'smaller' objects */
+        if (u->meta.job)
+                job_free(u->meta.job);
+
+        if (u->meta.load_state != UNIT_STUB)
+                if (UNIT_VTABLE(u)->done)
+                        UNIT_VTABLE(u)->done(u);
+
+        cgroup_bonding_free_list(u->meta.cgroup_bondings);
+
+        for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
+                bidi_set_free(u, u->meta.dependencies[d]);
+
+        free(u->meta.description);
+        free(u->meta.fragment_path);
+
+        while ((t = set_steal_first(u->meta.names)))
+                free(t);
+        set_free(u->meta.names);
+
+        free(u->meta.instance);
+
+        free(u);
+}
+
+UnitActiveState unit_active_state(Unit *u) {
+        assert(u);
+
+        if (u->meta.load_state != UNIT_LOADED)
+                return UNIT_INACTIVE;
+
+        return UNIT_VTABLE(u)->active_state(u);
+}
+
+const char* unit_sub_state_to_string(Unit *u) {
+        assert(u);
+
+        return UNIT_VTABLE(u)->sub_state_to_string(u);
+}
+
+static void complete_move(Set **s, Set **other) {
+        assert(s);
+        assert(other);
+
+        if (!*other)
+                return;
+
+        if (*s)
+                set_move(*s, *other);
+        else {
+                *s = *other;
+                *other = NULL;
+        }
+}
+
+static void merge_names(Unit *u, Unit *other) {
+        char *t;
+        Iterator i;
+
+        assert(u);
+        assert(other);
+
+        complete_move(&u->meta.names, &other->meta.names);
+
+        while ((t = set_steal_first(other->meta.names)))
+                free(t);
+
+        set_free(other->meta.names);
+        other->meta.names = NULL;
+        other->meta.id = NULL;
+
+        SET_FOREACH(t, u->meta.names, i)
+                assert_se(hashmap_replace(u->meta.manager->units, t, u) == 0);
+}
+
+static void merge_dependencies(Unit *u, Unit *other, UnitDependency d) {
+        Iterator i;
+        Unit *back;
+        int r;
+
+        assert(u);
+        assert(other);
+        assert(d < _UNIT_DEPENDENCY_MAX);
+
+        SET_FOREACH(back, other->meta.dependencies[d], i) {
+                UnitDependency k;
+
+                for (k = 0; k < _UNIT_DEPENDENCY_MAX; k++)
+                        if ((r = set_remove_and_put(back->meta.dependencies[k], other, u)) < 0) {
+
+                                if (r == -EEXIST)
+                                        set_remove(back->meta.dependencies[k], other);
+                                else
+                                        assert(r == -ENOENT);
+                        }
+        }
+
+        complete_move(&u->meta.dependencies[d], &other->meta.dependencies[d]);
+
+        set_free(other->meta.dependencies[d]);
+        other->meta.dependencies[d] = NULL;
+}
+
+int unit_merge(Unit *u, Unit *other) {
+        UnitDependency d;
+
+        assert(u);
+        assert(other);
+        assert(u->meta.manager == other->meta.manager);
+        assert(u->meta.type != _UNIT_TYPE_INVALID);
+
+        other = unit_follow_merge(other);
+
+        if (other == u)
+                return 0;
+
+        if (u->meta.type != other->meta.type)
+                return -EINVAL;
+
+        if (!streq_ptr(u->meta.instance, other->meta.instance))
+                return -EINVAL;
+
+        if (other->meta.load_state != UNIT_STUB &&
+            other->meta.load_state != UNIT_FAILED)
+                return -EEXIST;
+
+        if (other->meta.job)
+                return -EEXIST;
+
+        if (unit_active_state(other) != UNIT_INACTIVE)
+                return -EEXIST;
+
+        /* Merge names */
+        merge_names(u, other);
+
+        /* Merge dependencies */
+        for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++)
+                merge_dependencies(u, other, d);
+
+        other->meta.load_state = UNIT_MERGED;
+        other->meta.merged_into = u;
+
+        /* If there is still some data attached to the other node, we
+         * don't need it anymore, and can free it. */
+        if (other->meta.load_state != UNIT_STUB)
+                if (UNIT_VTABLE(other)->done)
+                        UNIT_VTABLE(other)->done(other);
+
+        unit_add_to_dbus_queue(u);
+        unit_add_to_cleanup_queue(other);
+
+        return 0;
+}
+
+int unit_merge_by_name(Unit *u, const char *name) {
+        Unit *other;
+        int r;
+        char *s = NULL;
+
+        assert(u);
+        assert(name);
+
+        if (unit_name_is_template(name)) {
+                if (!u->meta.instance)
+                        return -EINVAL;
+
+                if (!(s = unit_name_replace_instance(name, u->meta.instance)))
+                        return -ENOMEM;
+
+                name = s;
+        }
+
+        if (!(other = manager_get_unit(u->meta.manager, name)))
+                r = unit_add_name(u, name);
+        else
+                r = unit_merge(u, other);
+
+        free(s);
+        return r;
+}
+
+Unit* unit_follow_merge(Unit *u) {
+        assert(u);
+
+        while (u->meta.load_state == UNIT_MERGED)
+                assert_se(u = u->meta.merged_into);
+
+        return u;
+}
+
+int unit_add_exec_dependencies(Unit *u, ExecContext *c) {
+        int r;
+
+        assert(u);
+        assert(c);
+
+        if (c->std_output != EXEC_OUTPUT_KERNEL && c->std_output != EXEC_OUTPUT_SYSLOG)
+                return 0;
+
+        /* If syslog or kernel logging is requested, make sure our own
+         * logging daemon is run first. */
+
+        if ((r = unit_add_dependency_by_name(u, UNIT_AFTER, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
+                return r;
+
+        if (u->meta.manager->running_as != MANAGER_SESSION)
+                if ((r = unit_add_dependency_by_name(u, UNIT_REQUIRES, SPECIAL_LOGGER_SOCKET, NULL, true)) < 0)
+                        return r;
+
+        return 0;
+}
+
+const char *unit_description(Unit *u) {
+        assert(u);
+
+        if (u->meta.description)
+                return u->meta.description;
+
+        return u->meta.id;
+}
+
+void unit_dump(Unit *u, FILE *f, const char *prefix) {
+        char *t;
+        UnitDependency d;
+        Iterator i;
+        char *p2;
+        const char *prefix2;
+        CGroupBonding *b;
+        char
+                timestamp1[FORMAT_TIMESTAMP_MAX],
+                timestamp2[FORMAT_TIMESTAMP_MAX],
+                timestamp3[FORMAT_TIMESTAMP_MAX],
+                timestamp4[FORMAT_TIMESTAMP_MAX];
+
+        assert(u);
+        assert(u->meta.type >= 0);
+
+        if (!prefix)
+                prefix = "";
+        p2 = strappend(prefix, "\t");
+        prefix2 = p2 ? p2 : prefix;
+
+        fprintf(f,
+                "%s-> Unit %s:\n"
+                "%s\tDescription: %s\n"
+                "%s\tInstance: %s\n"
+                "%s\tUnit Load State: %s\n"
+                "%s\tUnit Active State: %s\n"
+                "%s\tInactive Exit Timestamp: %s\n"
+                "%s\tActive Enter Timestamp: %s\n"
+                "%s\tActive Exit Timestamp: %s\n"
+                "%s\tInactive Enter Timestamp: %s\n"
+                "%s\tGC Check Good: %s\n",
+                prefix, u->meta.id,
+                prefix, unit_description(u),
+                prefix, strna(u->meta.instance),
+                prefix, unit_load_state_to_string(u->meta.load_state),
+                prefix, unit_active_state_to_string(unit_active_state(u)),
+                prefix, strna(format_timestamp(timestamp1, sizeof(timestamp1), u->meta.inactive_exit_timestamp)),
+                prefix, strna(format_timestamp(timestamp2, sizeof(timestamp2), u->meta.active_enter_timestamp)),
+                prefix, strna(format_timestamp(timestamp3, sizeof(timestamp3), u->meta.active_exit_timestamp)),
+                prefix, strna(format_timestamp(timestamp4, sizeof(timestamp4), u->meta.inactive_enter_timestamp)),
+                prefix, yes_no(unit_check_gc(u)));
+
+        SET_FOREACH(t, u->meta.names, i)
+                fprintf(f, "%s\tName: %s\n", prefix, t);
+
+        if (u->meta.fragment_path)
+                fprintf(f, "%s\tFragment Path: %s\n", prefix, u->meta.fragment_path);
+
+        for (d = 0; d < _UNIT_DEPENDENCY_MAX; d++) {
+                Unit *other;
+
+                SET_FOREACH(other, u->meta.dependencies[d], i)
+                        fprintf(f, "%s\t%s: %s\n", prefix, unit_dependency_to_string(d), other->meta.id);
+        }
+
+        if (u->meta.load_state == UNIT_LOADED) {
+                fprintf(f,
+                        "%s\tRecursive Stop: %s\n"
+                        "%s\tStop When Unneeded: %s\n",
+                        prefix, yes_no(u->meta.recursive_stop),
+                        prefix, yes_no(u->meta.stop_when_unneeded));
+
+                LIST_FOREACH(by_unit, b, u->meta.cgroup_bondings)
+                        fprintf(f, "%s\tControlGroup: %s:%s\n",
+                                prefix, b->controller, b->path);
+
+                if (UNIT_VTABLE(u)->dump)
+                        UNIT_VTABLE(u)->dump(u, f, prefix2);
+
+        } else if (u->meta.load_state == UNIT_MERGED)
+                fprintf(f,
+                        "%s\tMerged into: %s\n",
+                        prefix, u->meta.merged_into->meta.id);
+
+        if (u->meta.job)
+                job_dump(u->meta.job, f, prefix2);
+
+        free(p2);
+}
+
+/* Common implementation for multiple backends */
+int unit_load_fragment_and_dropin(Unit *u) {
+        int r;
+
+        assert(u);
+
+        /* Load a .service file */
+        if ((r = unit_load_fragment(u)) < 0)
+                return r;
+
+        if (u->meta.load_state == UNIT_STUB)
+                return -ENOENT;
+
+        /* Load drop-in directory data */
+        if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
+                return r;
+
+        return 0;
+}
+
+/* Common implementation for multiple backends */
+int unit_load_fragment_and_dropin_optional(Unit *u) {
+        int r;
+
+        assert(u);
+
+        /* Same as unit_load_fragment_and_dropin(), but whether
+         * something can be loaded or not doesn't matter. */
+
+        /* Load a .service file */
+        if ((r = unit_load_fragment(u)) < 0)
+                return r;
+
+        if (u->meta.load_state == UNIT_STUB)
+                u->meta.load_state = UNIT_LOADED;
+
+        /* Load drop-in directory data */
+        if ((r = unit_load_dropin(unit_follow_merge(u))) < 0)
+                return r;
+
+        return 0;
+}
+
+/* Common implementation for multiple backends */
+int unit_load_nop(Unit *u) {
+        assert(u);
+
+        if (u->meta.load_state == UNIT_STUB)
+                u->meta.load_state = UNIT_LOADED;
+
+        return 0;
+}
+
+int unit_load(Unit *u) {
+        int r;
+
+        assert(u);
+
+        if (u->meta.in_load_queue) {
+                LIST_REMOVE(Meta, load_queue, u->meta.manager->load_queue, &u->meta);
+                u->meta.in_load_queue = false;
+        }
+
+        if (u->meta.type == _UNIT_TYPE_INVALID)
+                return -EINVAL;
+
+        if (u->meta.load_state != UNIT_STUB)
+                return 0;
+
+        if (UNIT_VTABLE(u)->load)
+                if ((r = UNIT_VTABLE(u)->load(u)) < 0)
+                        goto fail;
+
+        if (u->meta.load_state == UNIT_STUB) {
+                r = -ENOENT;
+                goto fail;
+        }
+
+        assert((u->meta.load_state != UNIT_MERGED) == !u->meta.merged_into);
+
+        unit_add_to_dbus_queue(unit_follow_merge(u));
+        unit_add_to_gc_queue(u);
+
+        return 0;
+
+fail:
+        u->meta.load_state = UNIT_FAILED;
+        unit_add_to_dbus_queue(u);
+
+        log_debug("Failed to load configuration for %s: %s", u->meta.id, strerror(-r));
+
+        return r;
+}
+
+/* Errors:
+ *         -EBADR:    This unit type does not support starting.
+ *         -EALREADY: Unit is already started.
+ *         -EAGAIN:   An operation is already in progress. Retry later.
+ */
+int unit_start(Unit *u) {
+        UnitActiveState state;
+
+        assert(u);
+
+        /* If this is already (being) started, then this will
+         * succeed. Note that this will even succeed if this unit is
+         * not startable by the user. This is relied on to detect when
+         * we need to wait for units and when waiting is finished. */
+        state = unit_active_state(u);
+        if (UNIT_IS_ACTIVE_OR_RELOADING(state))
+                return -EALREADY;
+
+        /* If it is stopped, but we cannot start it, then fail */
+        if (!UNIT_VTABLE(u)->start)
+                return -EBADR;
+
+        /* We don't suppress calls to ->start() here when we are
+         * already starting, to allow this request to be used as a
+         * "hurry up" call, for example when the unit is in some "auto
+         * restart" state where it waits for a holdoff timer to elapse
+         * before it will start again. */
+
+        unit_add_to_dbus_queue(u);
+        return UNIT_VTABLE(u)->start(u);
+}
+
+bool unit_can_start(Unit *u) {
+        assert(u);
+
+        return !!UNIT_VTABLE(u)->start;
+}
+
+/* Errors:
+ *         -EBADR:    This unit type does not support stopping.
+ *         -EALREADY: Unit is already stopped.
+ *         -EAGAIN:   An operation is already in progress. Retry later.
+ */
+int unit_stop(Unit *u) {
+        UnitActiveState state;
+
+        assert(u);
+
+        state = unit_active_state(u);
+        if (state == UNIT_INACTIVE)
+                return -EALREADY;
+
+        if (!UNIT_VTABLE(u)->stop)
+                return -EBADR;
+
+        unit_add_to_dbus_queue(u);
+        return UNIT_VTABLE(u)->stop(u);
+}
+
+/* Errors:
+ *         -EBADR:    This unit type does not support reloading.
+ *         -ENOEXEC:  Unit is not started.
+ *         -EAGAIN:   An operation is already in progress. Retry later.
+ */
+int unit_reload(Unit *u) {
+        UnitActiveState state;
+
+        assert(u);
+
+        if (!unit_can_reload(u))
+                return -EBADR;
+
+        state = unit_active_state(u);
+        if (unit_active_state(u) == UNIT_ACTIVE_RELOADING)
+                return -EALREADY;
+
+        if (unit_active_state(u) != UNIT_ACTIVE)
+                return -ENOEXEC;
+
+        unit_add_to_dbus_queue(u);
+        return UNIT_VTABLE(u)->reload(u);
+}
+
+bool unit_can_reload(Unit *u) {
+        assert(u);
+
+        if (!UNIT_VTABLE(u)->reload)
+                return false;
+
+        if (!UNIT_VTABLE(u)->can_reload)
+                return true;
+
+        return UNIT_VTABLE(u)->can_reload(u);
+}
+
+static void unit_check_uneeded(Unit *u) {
+        Iterator i;
+        Unit *other;
+
+        assert(u);
+
+        /* If this service shall be shut down when unneeded then do
+         * so. */
+
+        if (!u->meta.stop_when_unneeded)
+                return;
+
+        if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)))
+                return;
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        return;
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        return;
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_WANTED_BY], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        return;
+
+        log_debug("Service %s is not needed anymore. Stopping.", u->meta.id);
+
+        /* Ok, nobody needs us anymore. Sniff. Then let's commit suicide */
+        manager_add_job(u->meta.manager, JOB_STOP, u, JOB_FAIL, true, NULL);
+}
+
+static void retroactively_start_dependencies(Unit *u) {
+        Iterator i;
+        Unit *other;
+
+        assert(u);
+        assert(UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u)));
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
+                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
+                        manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
+                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
+                        manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
+                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
+                        manager_add_job(u->meta.manager, JOB_START, other, JOB_REPLACE, true, NULL);
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
+                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
+                        manager_add_job(u->meta.manager, JOB_START, other, JOB_FAIL, false, NULL);
+
+        SET_FOREACH(other, u->meta.dependencies[UNIT_CONFLICTS], i)
+                if (!UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(other)))
+                        manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
+}
+
+static void retroactively_stop_dependencies(Unit *u) {
+        Iterator i;
+        Unit *other;
+
+        assert(u);
+        assert(UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(u)));
+
+        if (u->meta.recursive_stop) {
+                /* Pull down units need us recursively if enabled */
+                SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRED_BY], i)
+                        if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                                manager_add_job(u->meta.manager, JOB_STOP, other, JOB_REPLACE, true, NULL);
+        }
+
+        /* Garbage collect services that might not be needed anymore, if enabled */
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        unit_check_uneeded(other);
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        unit_check_uneeded(other);
+        SET_FOREACH(other, u->meta.dependencies[UNIT_WANTS], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        unit_check_uneeded(other);
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        unit_check_uneeded(other);
+        SET_FOREACH(other, u->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i)
+                if (!UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(other)))
+                        unit_check_uneeded(other);
+}
+
+void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns) {
+        bool unexpected = false;
+        usec_t ts;
+
+        assert(u);
+        assert(os < _UNIT_ACTIVE_STATE_MAX);
+        assert(ns < _UNIT_ACTIVE_STATE_MAX);
+
+        /* Note that this is called for all low-level state changes,
+         * even if they might map to the same high-level
+         * UnitActiveState! That means that ns == os is OK an expected
+         * behaviour here. For example: if a mount point is remounted
+         * this function will be called too and the utmp code below
+         * relies on that! */
+
+        ts = now(CLOCK_REALTIME);
+
+        if (os == UNIT_INACTIVE && ns != UNIT_INACTIVE)
+                u->meta.inactive_exit_timestamp = ts;
+        else if (os != UNIT_INACTIVE && ns == UNIT_INACTIVE)
+                u->meta.inactive_enter_timestamp = ts;
+
+        if (!UNIT_IS_ACTIVE_OR_RELOADING(os) && UNIT_IS_ACTIVE_OR_RELOADING(ns))
+                u->meta.active_enter_timestamp = ts;
+        else if (UNIT_IS_ACTIVE_OR_RELOADING(os) && !UNIT_IS_ACTIVE_OR_RELOADING(ns))
+                u->meta.active_exit_timestamp = ts;
+
+        if (u->meta.job) {
+
+                if (u->meta.job->state == JOB_WAITING)
+
+                        /* So we reached a different state for this
+                         * job. Let's see if we can run it now if it
+                         * failed previously due to EAGAIN. */
+                        job_add_to_run_queue(u->meta.job);
+
+                else {
+                        assert(u->meta.job->state == JOB_RUNNING);
+
+                        /* Let's check whether this state change
+                         * constitutes a finished job, or maybe
+                         * cotradicts a running job and hence needs to
+                         * invalidate jobs. */
+
+                        switch (u->meta.job->type) {
+
+                        case JOB_START:
+                        case JOB_VERIFY_ACTIVE:
+
+                                if (UNIT_IS_ACTIVE_OR_RELOADING(ns))
+                                        job_finish_and_invalidate(u->meta.job, true);
+                                else if (ns != UNIT_ACTIVATING) {
+                                        unexpected = true;
+                                        job_finish_and_invalidate(u->meta.job, false);
+                                }
+
+                                break;
+
+                        case JOB_RELOAD:
+                        case JOB_RELOAD_OR_START:
+
+                                if (ns == UNIT_ACTIVE)
+                                        job_finish_and_invalidate(u->meta.job, true);
+                                else if (ns != UNIT_ACTIVATING && ns != UNIT_ACTIVE_RELOADING) {
+                                        unexpected = true;
+                                        job_finish_and_invalidate(u->meta.job, false);
+                                }
+
+                                break;
+
+                        case JOB_STOP:
+                        case JOB_RESTART:
+                        case JOB_TRY_RESTART:
+
+                                if (ns == UNIT_INACTIVE)
+                                        job_finish_and_invalidate(u->meta.job, true);
+                                else if (ns != UNIT_DEACTIVATING) {
+                                        unexpected = true;
+                                        job_finish_and_invalidate(u->meta.job, false);
+                                }
+
+                                break;
+
+                        default:
+                                assert_not_reached("Job type unknown");
+                        }
+                }
+        }
+
+        /* If this state change happened without being requested by a
+         * job, then let's retroactively start or stop dependencies */
+
+        if (unexpected) {
+                if (UNIT_IS_INACTIVE_OR_DEACTIVATING(os) && UNIT_IS_ACTIVE_OR_ACTIVATING(ns))
+                        retroactively_start_dependencies(u);
+                else if (UNIT_IS_ACTIVE_OR_ACTIVATING(os) && UNIT_IS_INACTIVE_OR_DEACTIVATING(ns))
+                        retroactively_stop_dependencies(u);
+        }
+
+        /* Some names are special */
+        if (UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
+                if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
+                        /* The bus just might have become available,
+                         * hence try to connect to it, if we aren't
+                         * yet connected. */
+                        bus_init_system(u->meta.manager);
+                        bus_init_api(u->meta.manager);
+                }
+
+                if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
+                        /* The syslog daemon just might have become
+                         * available, hence try to connect to it, if
+                         * we aren't yet connected. */
+                        log_open();
+
+                if (u->meta.type == UNIT_MOUNT)
+                        /* Another directory became available, let's
+                         * check if that is enough to write our utmp
+                         * entry. */
+                        manager_write_utmp_reboot(u->meta.manager);
+
+                if (u->meta.type == UNIT_TARGET)
+                        /* A target got activated, maybe this is a runlevel? */
+                        manager_write_utmp_runlevel(u->meta.manager, u);
+
+        } else if (!UNIT_IS_ACTIVE_OR_RELOADING(ns)) {
+
+                if (unit_has_name(u, SPECIAL_SYSLOG_SERVICE))
+                        /* The syslog daemon might just have
+                         * terminated, hence try to disconnect from
+                         * it. */
+                        log_close_syslog();
+
+                /* We don't care about D-Bus here, since we'll get an
+                 * asynchronous notification for it anyway. */
+        }
+
+        /* Maybe we finished startup and are now ready for being
+         * stopped because unneeded? */
+        unit_check_uneeded(u);
+
+        unit_add_to_dbus_queue(u);
+        unit_add_to_gc_queue(u);
+}
+
+int unit_watch_fd(Unit *u, int fd, uint32_t events, Watch *w) {
+        struct epoll_event ev;
+
+        assert(u);
+        assert(fd >= 0);
+        assert(w);
+        assert(w->type == WATCH_INVALID || (w->type == WATCH_FD && w->fd == fd && w->data.unit == u));
+
+        zero(ev);
+        ev.data.ptr = w;
+        ev.events = events;
+
+        if (epoll_ctl(u->meta.manager->epoll_fd,
+                      w->type == WATCH_INVALID ? EPOLL_CTL_ADD : EPOLL_CTL_MOD,
+                      fd,
+                      &ev) < 0)
+                return -errno;
+
+        w->fd = fd;
+        w->type = WATCH_FD;
+        w->data.unit = u;
+
+        return 0;
+}
+
+void unit_unwatch_fd(Unit *u, Watch *w) {
+        assert(u);
+        assert(w);
+
+        if (w->type == WATCH_INVALID)
+                return;
+
+        assert(w->type == WATCH_FD);
+        assert(w->data.unit == u);
+        assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
+
+        w->fd = -1;
+        w->type = WATCH_INVALID;
+        w->data.unit = NULL;
+}
+
+int unit_watch_pid(Unit *u, pid_t pid) {
+        assert(u);
+        assert(pid >= 1);
+
+        /* Watch a specific PID. We only support one unit watching
+         * each PID for now. */
+
+        return hashmap_put(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
+}
+
+void unit_unwatch_pid(Unit *u, pid_t pid) {
+        assert(u);
+        assert(pid >= 1);
+
+        hashmap_remove_value(u->meta.manager->watch_pids, UINT32_TO_PTR(pid), u);
+}
+
+int unit_watch_timer(Unit *u, usec_t delay, Watch *w) {
+        struct itimerspec its;
+        int flags, fd;
+        bool ours;
+
+        assert(u);
+        assert(w);
+        assert(w->type == WATCH_INVALID || (w->type == WATCH_TIMER && w->data.unit == u));
+
+        /* This will try to reuse the old timer if there is one */
+
+        if (w->type == WATCH_TIMER) {
+                ours = false;
+                fd = w->fd;
+        } else {
+                ours = true;
+                if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
+                        return -errno;
+        }
+
+        zero(its);
+
+        if (delay <= 0) {
+                /* Set absolute time in the past, but not 0, since we
+                 * don't want to disarm the timer */
+                its.it_value.tv_sec = 0;
+                its.it_value.tv_nsec = 1;
+
+                flags = TFD_TIMER_ABSTIME;
+        } else {
+                timespec_store(&its.it_value, delay);
+                flags = 0;
+        }
+
+        /* This will also flush the elapse counter */
+        if (timerfd_settime(fd, flags, &its, NULL) < 0)
+                goto fail;
+
+        if (w->type == WATCH_INVALID) {
+                struct epoll_event ev;
+
+                zero(ev);
+                ev.data.ptr = w;
+                ev.events = EPOLLIN;
+
+                if (epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
+                        goto fail;
+        }
+
+        w->fd = fd;
+        w->type = WATCH_TIMER;
+        w->data.unit = u;
+
+        return 0;
+
+fail:
+        if (ours)
+                close_nointr_nofail(fd);
+
+        return -errno;
+}
+
+void unit_unwatch_timer(Unit *u, Watch *w) {
+        assert(u);
+        assert(w);
+
+        if (w->type == WATCH_INVALID)
+                return;
+
+        assert(w->type == WATCH_TIMER && w->data.unit == u);
+
+        assert_se(epoll_ctl(u->meta.manager->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
+        close_nointr_nofail(w->fd);
+
+        w->fd = -1;
+        w->type = WATCH_INVALID;
+        w->data.unit = NULL;
+}
+
+bool unit_job_is_applicable(Unit *u, JobType j) {
+        assert(u);
+        assert(j >= 0 && j < _JOB_TYPE_MAX);
+
+        switch (j) {
+
+        case JOB_VERIFY_ACTIVE:
+        case JOB_START:
+                return true;
+
+        case JOB_STOP:
+        case JOB_RESTART:
+        case JOB_TRY_RESTART:
+                return unit_can_start(u);
+
+        case JOB_RELOAD:
+                return unit_can_reload(u);
+
+        case JOB_RELOAD_OR_START:
+                return unit_can_reload(u) && unit_can_start(u);
+
+        default:
+                assert_not_reached("Invalid job type");
+        }
+}
+
+int unit_add_dependency(Unit *u, UnitDependency d, Unit *other, bool add_reference) {
+
+        static const UnitDependency inverse_table[_UNIT_DEPENDENCY_MAX] = {
+                [UNIT_REQUIRES] = UNIT_REQUIRED_BY,
+                [UNIT_REQUIRES_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
+                [UNIT_WANTS] = UNIT_WANTED_BY,
+                [UNIT_REQUISITE] = UNIT_REQUIRED_BY,
+                [UNIT_REQUISITE_OVERRIDABLE] = UNIT_REQUIRED_BY_OVERRIDABLE,
+                [UNIT_REQUIRED_BY] = _UNIT_DEPENDENCY_INVALID,
+                [UNIT_REQUIRED_BY_OVERRIDABLE] = _UNIT_DEPENDENCY_INVALID,
+                [UNIT_WANTED_BY] = _UNIT_DEPENDENCY_INVALID,
+                [UNIT_CONFLICTS] = UNIT_CONFLICTS,
+                [UNIT_BEFORE] = UNIT_AFTER,
+                [UNIT_AFTER] = UNIT_BEFORE,
+                [UNIT_REFERENCES] = UNIT_REFERENCED_BY,
+                [UNIT_REFERENCED_BY] = UNIT_REFERENCES
+        };
+        int r, q = 0, v = 0, w = 0;
+
+        assert(u);
+        assert(d >= 0 && d < _UNIT_DEPENDENCY_MAX);
+        assert(inverse_table[d] != _UNIT_DEPENDENCY_INVALID);
+        assert(other);
+
+        /* We won't allow dependencies on ourselves. We will not
+         * consider them an error however. */
+        if (u == other)
+                return 0;
+
+        if (UNIT_VTABLE(u)->no_requires &&
+            (d == UNIT_REQUIRES ||
+             d == UNIT_REQUIRES_OVERRIDABLE ||
+             d == UNIT_REQUISITE ||
+             d == UNIT_REQUISITE_OVERRIDABLE)) {
+                    return -EINVAL;
+        }
+
+        if ((r = set_ensure_allocated(&u->meta.dependencies[d], trivial_hash_func, trivial_compare_func)) < 0 ||
+            (r = set_ensure_allocated(&other->meta.dependencies[inverse_table[d]], trivial_hash_func, trivial_compare_func)) < 0)
+                return r;
+
+        if (add_reference)
+                if ((r = set_ensure_allocated(&u->meta.dependencies[UNIT_REFERENCES], trivial_hash_func, trivial_compare_func)) < 0 ||
+                    (r = set_ensure_allocated(&other->meta.dependencies[UNIT_REFERENCED_BY], trivial_hash_func, trivial_compare_func)) < 0)
+                        return r;
+
+        if ((q = set_put(u->meta.dependencies[d], other)) < 0)
+                return q;
+
+        if ((v = set_put(other->meta.dependencies[inverse_table[d]], u)) < 0) {
+                r = v;
+                goto fail;
+        }
+
+        if (add_reference) {
+                if ((w = set_put(u->meta.dependencies[UNIT_REFERENCES], other)) < 0) {
+                        r = w;
+                        goto fail;
+                }
+
+                if ((r = set_put(other->meta.dependencies[UNIT_REFERENCED_BY], u)) < 0)
+                        goto fail;
+        }
+
+        unit_add_to_dbus_queue(u);
+        return 0;
+
+fail:
+        if (q > 0)
+                set_remove(u->meta.dependencies[d], other);
+
+        if (v > 0)
+                set_remove(other->meta.dependencies[inverse_table[d]], u);
+
+        if (w > 0)
+                set_remove(u->meta.dependencies[UNIT_REFERENCES], other);
+
+        return r;
+}
+
+static const char *resolve_template(Unit *u, const char *name, const char*path, char **p) {
+        char *s;
+
+        assert(u);
+        assert(name || path);
+
+        if (!name)
+                name = file_name_from_path(path);
+
+        if (!unit_name_is_template(name)) {
+                *p = NULL;
+                return name;
+        }
+
+        if (u->meta.instance)
+                s = unit_name_replace_instance(name, u->meta.instance);
+        else {
+                char *i;
+
+                if (!(i = unit_name_to_prefix(u->meta.id)))
+                        return NULL;
+
+                s = unit_name_replace_instance(name, i);
+                free(i);
+        }
+
+        if (!s)
+                return NULL;
+
+        *p = s;
+        return s;
+}
+
+int unit_add_dependency_by_name(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
+        Unit *other;
+        int r;
+        char *s;
+
+        assert(u);
+        assert(name || path);
+
+        if (!(name = resolve_template(u, name, path, &s)))
+                return -ENOMEM;
+
+        if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
+                goto finish;
+
+        r = unit_add_dependency(u, d, other, add_reference);
+
+finish:
+        free(s);
+        return r;
+}
+
+int unit_add_dependency_by_name_inverse(Unit *u, UnitDependency d, const char *name, const char *path, bool add_reference) {
+        Unit *other;
+        int r;
+        char *s;
+
+        assert(u);
+        assert(name || path);
+
+        if (!(name = resolve_template(u, name, path, &s)))
+                return -ENOMEM;
+
+        if ((r = manager_load_unit(u->meta.manager, name, path, &other)) < 0)
+                goto finish;
+
+        r = unit_add_dependency(other, d, u, add_reference);
+
+finish:
+        free(s);
+        return r;
+}
+
+int set_unit_path(const char *p) {
+        char *cwd, *c;
+        int r;
+
+        /* This is mostly for debug purposes */
+
+        if (path_is_absolute(p)) {
+                if (!(c = strdup(p)))
+                        return -ENOMEM;
+        } else {
+                if (!(cwd = get_current_dir_name()))
+                        return -errno;
+
+                r = asprintf(&c, "%s/%s", cwd, p);
+                free(cwd);
+
+                if (r < 0)
+                        return -ENOMEM;
+        }
+
+        if (setenv("SYSTEMD_UNIT_PATH", c, 0) < 0) {
+                r = -errno;
+                free(c);
+                return r;
+        }
+
+        return 0;
+}
+
+char *unit_dbus_path(Unit *u) {
+        char *p, *e;
+
+        assert(u);
+
+        if (!(e = bus_path_escape(u->meta.id)))
+                return NULL;
+
+        if (asprintf(&p, "/org/freedesktop/systemd1/unit/%s", e) < 0) {
+                free(e);
+                return NULL;
+        }
+
+        free(e);
+        return p;
+}
+
+int unit_add_cgroup(Unit *u, CGroupBonding *b) {
+        CGroupBonding *l;
+        int r;
+
+        assert(u);
+        assert(b);
+        assert(b->path);
+
+        /* Ensure this hasn't been added yet */
+        assert(!b->unit);
+
+        l = hashmap_get(u->meta.manager->cgroup_bondings, b->path);
+        LIST_PREPEND(CGroupBonding, by_path, l, b);
+
+        if ((r = hashmap_replace(u->meta.manager->cgroup_bondings, b->path, l)) < 0) {
+                LIST_REMOVE(CGroupBonding, by_path, l, b);
+                return r;
+        }
+
+        LIST_PREPEND(CGroupBonding, by_unit, u->meta.cgroup_bondings, b);
+        b->unit = u;
+
+        return 0;
+}
+
+static char *default_cgroup_path(Unit *u) {
+        char *p;
+        int r;
+
+        assert(u);
+
+        if (u->meta.instance) {
+                char *t;
+
+                if (!(t = unit_name_template(u->meta.id)))
+                        return NULL;
+
+                r = asprintf(&p, "%s/%s/%s", u->meta.manager->cgroup_hierarchy, t, u->meta.instance);
+                free(t);
+        } else
+                r = asprintf(&p, "%s/%s", u->meta.manager->cgroup_hierarchy, u->meta.id);
+
+        return r < 0 ? NULL : p;
+}
+
+int unit_add_cgroup_from_text(Unit *u, const char *name) {
+        size_t n;
+        char *controller = NULL, *path = NULL;
+        CGroupBonding *b = NULL;
+        int r;
+
+        assert(u);
+        assert(name);
+
+        /* Detect controller name */
+        n = strcspn(name, ":");
+
+        if (name[n] == 0 ||
+            (name[n] == ':' && name[n+1] == 0)) {
+
+                /* Only controller name, no path? */
+
+                if (!(path = default_cgroup_path(u)))
+                        return -ENOMEM;
+
+        } else {
+                const char *p;
+
+                /* Controller name, and path. */
+                p = name+n+1;
+
+                if (!path_is_absolute(p))
+                        return -EINVAL;
+
+                if (!(path = strdup(p)))
+                        return -ENOMEM;
+        }
+
+        if (n > 0)
+                controller = strndup(name, n);
+        else
+                controller = strdup(u->meta.manager->cgroup_controller);
+
+        if (!controller) {
+                r = -ENOMEM;
+                goto fail;
+        }
+
+        if (cgroup_bonding_find_list(u->meta.cgroup_bondings, controller)) {
+                r = -EEXIST;
+                goto fail;
+        }
+
+        if (!(b = new0(CGroupBonding, 1))) {
+                r = -ENOMEM;
+                goto fail;
+        }
+
+        b->controller = controller;
+        b->path = path;
+        b->only_us = false;
+        b->clean_up = false;
+
+        if ((r = unit_add_cgroup(u, b)) < 0)
+                goto fail;
+
+        return 0;
+
+fail:
+        free(path);
+        free(controller);
+        free(b);
+
+        return r;
+}
+
+int unit_add_default_cgroup(Unit *u) {
+        CGroupBonding *b;
+        int r = -ENOMEM;
+
+        assert(u);
+
+        /* Adds in the default cgroup data, if it wasn't specified yet */
+
+        if (unit_get_default_cgroup(u))
+                return 0;
+
+        if (!(b = new0(CGroupBonding, 1)))
+                return -ENOMEM;
+
+        if (!(b->controller = strdup(u->meta.manager->cgroup_controller)))
+                goto fail;
+
+        if (!(b->path = default_cgroup_path(u)))
+                goto fail;
+
+        b->clean_up = true;
+        b->only_us = true;
+
+        if ((r = unit_add_cgroup(u, b)) < 0)
+                goto fail;
+
+        return 0;
+
+fail:
+        free(b->path);
+        free(b->controller);
+        free(b);
+
+        return r;
+}
+
+CGroupBonding* unit_get_default_cgroup(Unit *u) {
+        assert(u);
+
+        return cgroup_bonding_find_list(u->meta.cgroup_bondings, u->meta.manager->cgroup_controller);
+}
+
+int unit_load_related_unit(Unit *u, const char *type, Unit **_found) {
+        char *t;
+        int r;
+
+        assert(u);
+        assert(type);
+        assert(_found);
+
+        if (!(t = unit_name_change_suffix(u->meta.id, type)))
+                return -ENOMEM;
+
+        assert(!unit_has_name(u, t));
+
+        r = manager_load_unit(u->meta.manager, t, NULL, _found);
+        free(t);
+
+        assert(r < 0 || *_found != u);
+
+        return r;
+}
+
+int unit_get_related_unit(Unit *u, const char *type, Unit **_found) {
+        Unit *found;
+        char *t;
+
+        assert(u);
+        assert(type);
+        assert(_found);
+
+        if (!(t = unit_name_change_suffix(u->meta.id, type)))
+                return -ENOMEM;
+
+        assert(!unit_has_name(u, t));
+
+        found = manager_get_unit(u->meta.manager, t);
+        free(t);
+
+        if (!found)
+                return -ENOENT;
+
+        *_found = found;
+        return 0;
+}
+
+static char *specifier_prefix_and_instance(char specifier, void *data, void *userdata) {
+        Unit *u = userdata;
+        assert(u);
+
+        return unit_name_to_prefix_and_instance(u->meta.id);
+}
+
+static char *specifier_prefix(char specifier, void *data, void *userdata) {
+        Unit *u = userdata;
+        assert(u);
+
+        return unit_name_to_prefix(u->meta.id);
+}
+
+static char *specifier_prefix_unescaped(char specifier, void *data, void *userdata) {
+        Unit *u = userdata;
+        char *p, *r;
+
+        assert(u);
+
+        if (!(p = unit_name_to_prefix(u->meta.id)))
+                return NULL;
+
+        r = unit_name_unescape(p);
+        free(p);
+
+        return r;
+}
+
+static char *specifier_instance_unescaped(char specifier, void *data, void *userdata) {
+        Unit *u = userdata;
+        assert(u);
+
+        if (u->meta.instance)
+                return unit_name_unescape(u->meta.instance);
+
+        return strdup("");
+}
+
+char *unit_name_printf(Unit *u, const char* format) {
+
+        /*
+         * This will use the passed string as format string and
+         * replace the following specifiers:
+         *
+         * %n: the full id of the unit                 (foo@bar.waldo)
+         * %N: the id of the unit without the suffix   (foo@bar)
+         * %p: the prefix                              (foo)
+         * %i: the instance                            (bar)
+         */
+
+        const Specifier table[] = {
+                { 'n', specifier_string,              u->meta.id },
+                { 'N', specifier_prefix_and_instance, NULL },
+                { 'p', specifier_prefix,              NULL },
+                { 'i', specifier_string,              u->meta.instance },
+                { 0, NULL, NULL }
+        };
+
+        assert(u);
+        assert(format);
+
+        return specifier_printf(format, table, u);
+}
+
+char *unit_full_printf(Unit *u, const char *format) {
+
+        /* This is similar to unit_name_printf() but also supports
+         * unescaping */
+
+        const Specifier table[] = {
+                { 'n', specifier_string,              u->meta.id },
+                { 'N', specifier_prefix_and_instance, NULL },
+                { 'p', specifier_prefix,              NULL },
+                { 'P', specifier_prefix_unescaped,    NULL },
+                { 'i', specifier_string,              u->meta.instance },
+                { 'I', specifier_instance_unescaped,  NULL },
+                { 0, NULL, NULL }
+        };
+
+        assert(u);
+        assert(format);
+
+        return specifier_printf(format, table, u);
+}
+
+char **unit_full_printf_strv(Unit *u, char **l) {
+        size_t n;
+        char **r, **i, **j;
+
+        /* Applies unit_full_printf to every entry in l */
+
+        assert(u);
+
+        n = strv_length(l);
+        if (!(r = new(char*, n+1)))
+                return NULL;
+
+        for (i = l, j = r; *i; i++, j++)
+                if (!(*j = unit_full_printf(u, *i)))
+                        goto fail;
+
+        *j = NULL;
+        return r;
+
+fail:
+        j--;
+        while (j >= r)
+                free(*j);
+
+        free(r);
+
+        return NULL;
+}
+
+int unit_watch_bus_name(Unit *u, const char *name) {
+        assert(u);
+        assert(name);
+
+        /* Watch a specific name on the bus. We only support one unit
+         * watching each name for now. */
+
+        return hashmap_put(u->meta.manager->watch_bus, name, u);
+}
+
+void unit_unwatch_bus_name(Unit *u, const char *name) {
+        assert(u);
+        assert(name);
+
+        hashmap_remove_value(u->meta.manager->watch_bus, name, u);
+}
+
+bool unit_can_serialize(Unit *u) {
+        assert(u);
+
+        return UNIT_VTABLE(u)->serialize && UNIT_VTABLE(u)->deserialize_item;
+}
+
+int unit_serialize(Unit *u, FILE *f, FDSet *fds) {
+        int r;
+
+        assert(u);
+        assert(f);
+        assert(fds);
+
+        if (!unit_can_serialize(u))
+                return 0;
+
+        if ((r = UNIT_VTABLE(u)->serialize(u, f, fds)) < 0)
+                return r;
+
+        /* End marker */
+        fputc('\n', f);
+        return 0;
+}
+
+void unit_serialize_item_format(Unit *u, FILE *f, const char *key, const char *format, ...) {
+        va_list ap;
+
+        assert(u);
+        assert(f);
+        assert(key);
+        assert(format);
+
+        fputs(key, f);
+        fputc('=', f);
+
+        va_start(ap, format);
+        vfprintf(f, format, ap);
+        va_end(ap);
+
+        fputc('\n', f);
+}
+
+void unit_serialize_item(Unit *u, FILE *f, const char *key, const char *value) {
+        assert(u);
+        assert(f);
+        assert(key);
+        assert(value);
+
+        fprintf(f, "%s=%s\n", key, value);
+}
+
+int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
+        int r;
+
+        assert(u);
+        assert(f);
+        assert(fds);
+
+        if (!unit_can_serialize(u))
+                return 0;
+
+        for (;;) {
+                char line[1024], *l, *v;
+                size_t k;
+
+                if (!fgets(line, sizeof(line), f)) {
+                        if (feof(f))
+                                return 0;
+                        return -errno;
+                }
+
+                l = strstrip(line);
+
+                /* End marker */
+                if (l[0] == 0)
+                        return 0;
+
+                k = strcspn(l, "=");
+
+                if (l[k] == '=') {
+                        l[k] = 0;
+                        v = l+k+1;
+                } else
+                        v = l+k;
+
+                if ((r = UNIT_VTABLE(u)->deserialize_item(u, l, v, fds)) < 0)
+                        return r;
+        }
+}
+
+int unit_add_node_link(Unit *u, const char *what, bool wants) {
+        Unit *device;
+        char *e;
+        int r;
+
+        assert(u);
+
+        if (!what)
+                return 0;
+
+        /* Adds in links to the device node that this unit is based on */
+
+        if (!is_device_path(what))
+                return 0;
+
+        if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
+                return -ENOMEM;
+
+        r = manager_load_unit(u->meta.manager, e, NULL, &device);
+        free(e);
+
+        if (r < 0)
+                return r;
+
+        if ((r = unit_add_dependency(u, UNIT_AFTER, device, true)) < 0)
+                return r;
+
+        if ((r = unit_add_dependency(u, UNIT_REQUIRES, device, true)) < 0)
+                return r;
+
+        if (wants)
+                if ((r = unit_add_dependency(device, UNIT_WANTS, u, false)) < 0)
+                        return r;
+
+        return 0;
+}
+
+static const char* const unit_type_table[_UNIT_TYPE_MAX] = {
+        [UNIT_SERVICE] = "service",
+        [UNIT_TIMER] = "timer",
+        [UNIT_SOCKET] = "socket",
+        [UNIT_TARGET] = "target",
+        [UNIT_DEVICE] = "device",
+        [UNIT_MOUNT] = "mount",
+        [UNIT_AUTOMOUNT] = "automount",
+        [UNIT_SNAPSHOT] = "snapshot",
+        [UNIT_SWAP] = "swap"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType);
+
+static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = {
+        [UNIT_STUB] = "stub",
+        [UNIT_LOADED] = "loaded",
+        [UNIT_FAILED] = "failed",
+        [UNIT_MERGED] = "merged"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState);
+
+static const char* const unit_active_state_table[_UNIT_ACTIVE_STATE_MAX] = {
+        [UNIT_ACTIVE] = "active",
+        [UNIT_INACTIVE] = "inactive",
+        [UNIT_ACTIVATING] = "activating",
+        [UNIT_DEACTIVATING] = "deactivating"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(unit_active_state, UnitActiveState);
+
+static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = {
+        [UNIT_REQUIRES] = "Requires",
+        [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable",
+        [UNIT_WANTS] = "Wants",
+        [UNIT_REQUISITE] = "Requisite",
+        [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable",
+        [UNIT_REQUIRED_BY] = "RequiredBy",
+        [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable",
+        [UNIT_WANTED_BY] = "WantedBy",
+        [UNIT_CONFLICTS] = "Conflicts",
+        [UNIT_BEFORE] = "Before",
+        [UNIT_AFTER] = "After",
+        [UNIT_REFERENCES] = "References",
+        [UNIT_REFERENCED_BY] = "ReferencedBy"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency);
+
+static const char* const kill_mode_table[_KILL_MODE_MAX] = {
+        [KILL_CONTROL_GROUP] = "control-group",
+        [KILL_PROCESS_GROUP] = "process-group",
+        [KILL_PROCESS] = "process",
+        [KILL_NONE] = "none"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);