chiark / gitweb /
unit: use weaker dependencies between mount and device units in --user mode
[elogind.git] / src / core / timer.c
index e318fee2010eb927f32d538fa6bd872221bd265a..940550194b15e238b2045d3519e2d65ecd2a873a 100644 (file)
@@ -6,16 +6,16 @@
   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
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 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.
+  Lesser General Public License for more details.
 
-  You should have received a copy of the GNU General Public License
+  You should have received a copy of the GNU Lesser General Public License
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
@@ -26,7 +26,8 @@
 #include "timer.h"
 #include "dbus-timer.h"
 #include "special.h"
-#include "bus-errors.h"
+#include "bus-util.h"
+#include "bus-error.h"
 
 static const UnitActiveState state_translation_table[_TIMER_STATE_MAX] = {
         [TIMER_DEAD] = UNIT_INACTIVE,
@@ -36,29 +37,45 @@ static const UnitActiveState state_translation_table[_TIMER_STATE_MAX] = {
         [TIMER_FAILED] = UNIT_FAILED
 };
 
+static int timer_dispatch(sd_event_source *s, uint64_t usec, void *userdata);
+
 static void timer_init(Unit *u) {
         Timer *t = TIMER(u);
 
         assert(u);
         assert(u->load_state == UNIT_STUB);
 
-        t->next_elapse = (usec_t) -1;
+        t->next_elapse_monotonic_or_boottime = USEC_INFINITY;
+        t->next_elapse_realtime = USEC_INFINITY;
+        t->accuracy_usec = u->manager->default_timer_accuracy_usec;
 }
 
-static void timer_done(Unit *u) {
-        Timer *t = TIMER(u);
+void timer_free_values(Timer *t) {
         TimerValue *v;
 
         assert(t);
 
         while ((v = t->values)) {
-                LIST_REMOVE(TimerValue, value, t->values, v);
+                LIST_REMOVE(value, t->values, v);
+
+                if (v->calendar_spec)
+                        calendar_spec_free(v->calendar_spec);
+
                 free(v);
         }
+}
 
-        unit_unwatch_timer(u, &t->timer_watch);
+static void timer_done(Unit *u) {
+        Timer *t = TIMER(u);
+
+        assert(t);
 
-        unit_ref_unset(&t->unit);
+        timer_free_values(t);
+
+        t->monotonic_event_source = sd_event_source_unref(t->monotonic_event_source);
+        t->realtime_event_source = sd_event_source_unref(t->realtime_event_source);
+
+        free(t->stamp_path);
 }
 
 static int timer_verify(Timer *t) {
@@ -68,7 +85,7 @@ static int timer_verify(Timer *t) {
                 return 0;
 
         if (!t->values) {
-                log_error("%s lacks value setting. Refusing.", UNIT(t)->id);
+                log_unit_error(UNIT(t)->id, "%s lacks value setting. Refusing.", UNIT(t)->id);
                 return -EINVAL;
         }
 
@@ -77,20 +94,71 @@ static int timer_verify(Timer *t) {
 
 static int timer_add_default_dependencies(Timer *t) {
         int r;
+        TimerValue *v;
 
         assert(t);
 
-        if (UNIT(t)->manager->running_as == MANAGER_SYSTEM) {
-                if ((r = unit_add_dependency_by_name(UNIT(t), UNIT_BEFORE, SPECIAL_BASIC_TARGET, NULL, true)) < 0)
-                        return r;
+        r = unit_add_dependency_by_name(UNIT(t), UNIT_BEFORE, SPECIAL_TIMERS_TARGET, NULL, true);
+        if (r < 0)
+                return r;
 
-                if ((r = unit_add_two_dependencies_by_name(UNIT(t), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true)) < 0)
+        if (UNIT(t)->manager->running_as == SYSTEMD_SYSTEM) {
+                r = unit_add_two_dependencies_by_name(UNIT(t), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true);
+                if (r < 0)
                         return r;
+
+                LIST_FOREACH(value, v, t->values) {
+                        if (v->base == TIMER_CALENDAR) {
+                                r = unit_add_dependency_by_name(UNIT(t), UNIT_AFTER, SPECIAL_TIME_SYNC_TARGET, NULL, true);
+                                if (r < 0)
+                                        return r;
+                                break;
+                        }
+                }
         }
 
         return unit_add_two_dependencies_by_name(UNIT(t), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true);
 }
 
+static int timer_setup_persistent(Timer *t) {
+        int r;
+
+        assert(t);
+
+        if (!t->persistent)
+                return 0;
+
+        if (UNIT(t)->manager->running_as == SYSTEMD_SYSTEM) {
+
+                r = unit_require_mounts_for(UNIT(t), "/var/lib/systemd/timers");
+                if (r < 0)
+                        return r;
+
+                t->stamp_path = strappend("/var/lib/systemd/timers/stamp-", UNIT(t)->id);
+        } else {
+                const char *e;
+
+                e = getenv("XDG_DATA_HOME");
+                if (e)
+                        t->stamp_path = strjoin(e, "/systemd/timers/stamp-", UNIT(t)->id, NULL);
+                else {
+
+                        _cleanup_free_ char *h = NULL;
+
+                        r = get_home_dir(&h);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to determine home directory: %m");
+
+                        t->stamp_path = strjoin(h, "/.local/share/systemd/timers/stamp-", UNIT(t)->id, NULL);
+                }
+        }
+
+        if (!t->stamp_path)
+                return log_oom();
+
+        return 0;
+}
+
 static int timer_load(Unit *u) {
         Timer *t = TIMER(u);
         int r;
@@ -98,53 +166,82 @@ static int timer_load(Unit *u) {
         assert(u);
         assert(u->load_state == UNIT_STUB);
 
-        if ((r = unit_load_fragment_and_dropin(u)) < 0)
+        r = unit_load_fragment_and_dropin(u);
+        if (r < 0)
                 return r;
 
         if (u->load_state == UNIT_LOADED) {
 
-                if (!UNIT_DEREF(t->unit)) {
+                if (set_isempty(u->dependencies[UNIT_TRIGGERS])) {
                         Unit *x;
 
                         r = unit_load_related_unit(u, ".service", &x);
                         if (r < 0)
                                 return r;
 
-                        unit_ref_set(&t->unit, x);
+                        r = unit_add_two_dependencies(u, UNIT_BEFORE, UNIT_TRIGGERS, x, true);
+                        if (r < 0)
+                                return r;
                 }
 
-                r = unit_add_two_dependencies(u, UNIT_BEFORE, UNIT_TRIGGERS, UNIT_DEREF(t->unit), true);
+                r = timer_setup_persistent(t);
                 if (r < 0)
                         return r;
 
-                if (UNIT(t)->default_dependencies)
-                        if ((r = timer_add_default_dependencies(t)) < 0)
+                if (u->default_dependencies) {
+                        r = timer_add_default_dependencies(t);
+                        if (r < 0)
                                 return r;
+                }
         }
 
         return timer_verify(t);
 }
 
 static void timer_dump(Unit *u, FILE *f, const char *prefix) {
+        char buf[FORMAT_TIMESPAN_MAX];
         Timer *t = TIMER(u);
+        Unit *trigger;
         TimerValue *v;
-        char
-                timespan1[FORMAT_TIMESPAN_MAX];
+
+        trigger = UNIT_TRIGGER(u);
 
         fprintf(f,
                 "%sTimer State: %s\n"
                 "%sResult: %s\n"
-                "%sUnit: %s\n",
+                "%sUnit: %s\n"
+                "%sPersistent: %s\n"
+                "%sWakeSystem: %s\n"
+                "%sAccuracy: %s\n",
                 prefix, timer_state_to_string(t->state),
                 prefix, timer_result_to_string(t->result),
-                prefix, UNIT_DEREF(t->unit)->id);
+                prefix, trigger ? trigger->id : "n/a",
+                prefix, yes_no(t->persistent),
+                prefix, yes_no(t->wake_system),
+                prefix, format_timespan(buf, sizeof(buf), t->accuracy_usec, 1));
 
-        LIST_FOREACH(value, v, t->values)
-                fprintf(f,
-                        "%s%s: %s\n",
-                        prefix,
-                        timer_base_to_string(v->base),
-                        strna(format_timespan(timespan1, sizeof(timespan1), v->value)));
+        LIST_FOREACH(value, v, t->values) {
+
+                if (v->base == TIMER_CALENDAR) {
+                        _cleanup_free_ char *p = NULL;
+
+                        calendar_spec_to_string(v->calendar_spec, &p);
+
+                        fprintf(f,
+                                "%s%s: %s\n",
+                                prefix,
+                                timer_base_to_string(v->base),
+                                strna(p));
+                } else  {
+                        char timespan1[FORMAT_TIMESPAN_MAX];
+
+                        fprintf(f,
+                                "%s%s: %s\n",
+                                prefix,
+                                timer_base_to_string(v->base),
+                                format_timespan(timespan1, sizeof(timespan1), v->value, 0));
+                }
+        }
 }
 
 static void timer_set_state(Timer *t, TimerState state) {
@@ -154,14 +251,16 @@ static void timer_set_state(Timer *t, TimerState state) {
         old_state = t->state;
         t->state = state;
 
-        if (state != TIMER_WAITING)
-                unit_unwatch_timer(UNIT(t), &t->timer_watch);
+        if (state != TIMER_WAITING) {
+                t->monotonic_event_source = sd_event_source_unref(t->monotonic_event_source);
+                t->realtime_event_source = sd_event_source_unref(t->realtime_event_source);
+        }
 
         if (state != old_state)
-                log_debug("%s changed %s -> %s",
-                          UNIT(t)->id,
-                          timer_state_to_string(old_state),
-                          timer_state_to_string(state));
+                log_unit_debug(UNIT(t)->id,
+                               "%s changed %s -> %s", UNIT(t)->id,
+                               timer_state_to_string(old_state),
+                               timer_state_to_string(state));
 
         unit_notify(UNIT(t), state_translation_table[old_state], state_translation_table[state], true);
 }
@@ -194,126 +293,261 @@ static void timer_enter_dead(Timer *t, TimerResult f) {
         timer_set_state(t, t->result != TIMER_SUCCESS ? TIMER_FAILED : TIMER_DEAD);
 }
 
+static usec_t monotonic_to_boottime(usec_t t) {
+        usec_t a, b;
+
+        if (t <= 0)
+                return 0;
+
+        a = now(CLOCK_BOOTTIME);
+        b = now(CLOCK_MONOTONIC);
+
+        if (t + a > b)
+                return t + a - b;
+        else
+                return 0;
+}
+
 static void timer_enter_waiting(Timer *t, bool initial) {
+        bool found_monotonic = false, found_realtime = false;
+        usec_t ts_realtime, ts_monotonic;
+        usec_t base = 0;
         TimerValue *v;
-        usec_t base = 0, delay, n;
-        bool found = false;
         int r;
 
-        n = now(CLOCK_MONOTONIC);
+        /* If we shall wake the system we use the boottime clock
+         * rather than the monotonic clock. */
+
+        ts_realtime = now(CLOCK_REALTIME);
+        ts_monotonic = now(t->wake_system ? CLOCK_BOOTTIME : CLOCK_MONOTONIC);
+        t->next_elapse_monotonic_or_boottime = t->next_elapse_realtime = 0;
 
         LIST_FOREACH(value, v, t->values) {
 
                 if (v->disabled)
                         continue;
 
-                switch (v->base) {
+                if (v->base == TIMER_CALENDAR) {
+                        usec_t b;
+
+                        /* If we know the last time this was
+                         * triggered, schedule the job based relative
+                         * to that. If we don't just start from
+                         * now. */
+
+                        b = t->last_trigger.realtime > 0 ? t->last_trigger.realtime : ts_realtime;
 
-                case TIMER_ACTIVE:
-                        if (state_translation_table[t->state] == UNIT_ACTIVE)
-                                base = UNIT(t)->inactive_exit_timestamp.monotonic;
+                        r = calendar_spec_next_usec(v->calendar_spec, b, &v->next_elapse);
+                        if (r < 0)
+                                continue;
+
+                        if (!found_realtime)
+                                t->next_elapse_realtime = v->next_elapse;
                         else
-                                base = n;
-                        break;
+                                t->next_elapse_realtime = MIN(t->next_elapse_realtime, v->next_elapse);
 
-                case TIMER_BOOT:
-                        /* CLOCK_MONOTONIC equals the uptime on Linux */
-                        base = 0;
-                        break;
+                        found_realtime = true;
 
-                case TIMER_STARTUP:
-                        base = UNIT(t)->manager->startup_timestamp.monotonic;
-                        break;
+                } else  {
+                        switch (v->base) {
 
-                case TIMER_UNIT_ACTIVE:
+                        case TIMER_ACTIVE:
+                                if (state_translation_table[t->state] == UNIT_ACTIVE)
+                                        base = UNIT(t)->inactive_exit_timestamp.monotonic;
+                                else
+                                        base = ts_monotonic;
+                                break;
 
-                        if (UNIT_DEREF(t->unit)->inactive_exit_timestamp.monotonic <= 0)
-                                continue;
+                        case TIMER_BOOT:
+                                /* CLOCK_MONOTONIC equals the uptime on Linux */
+                                base = 0;
+                                break;
 
-                        base = UNIT_DEREF(t->unit)->inactive_exit_timestamp.monotonic;
-                        break;
+                        case TIMER_STARTUP:
+                                base = UNIT(t)->manager->userspace_timestamp.monotonic;
+                                break;
 
-                case TIMER_UNIT_INACTIVE:
+                        case TIMER_UNIT_ACTIVE:
 
-                        if (UNIT_DEREF(t->unit)->inactive_enter_timestamp.monotonic <= 0)
-                                continue;
+                                base = UNIT_TRIGGER(UNIT(t))->inactive_exit_timestamp.monotonic;
 
-                        base = UNIT_DEREF(t->unit)->inactive_enter_timestamp.monotonic;
-                        break;
+                                if (base <= 0)
+                                        base = t->last_trigger.monotonic;
 
-                default:
-                        assert_not_reached("Unknown timer base");
-                }
+                                if (base <= 0)
+                                        continue;
 
-                v->next_elapse = base + v->value;
+                                break;
 
-                if (!initial && v->next_elapse < n) {
-                        v->disabled = true;
-                        continue;
-                }
+                        case TIMER_UNIT_INACTIVE:
 
-                if (!found)
-                        t->next_elapse = v->next_elapse;
-                else
-                        t->next_elapse = MIN(t->next_elapse, v->next_elapse);
+                                base = UNIT_TRIGGER(UNIT(t))->inactive_enter_timestamp.monotonic;
+
+                                if (base <= 0)
+                                        base = t->last_trigger.monotonic;
+
+                                if (base <= 0)
+                                        continue;
 
-                found = true;
+                                break;
+
+                        default:
+                                assert_not_reached("Unknown timer base");
+                        }
+
+                        if (t->wake_system)
+                                base = monotonic_to_boottime(base);
+
+                        v->next_elapse = base + v->value;
+
+                        if (!initial && v->next_elapse < ts_monotonic && IN_SET(v->base, TIMER_ACTIVE, TIMER_BOOT, TIMER_STARTUP)) {
+                                /* This is a one time trigger, disable it now */
+                                v->disabled = true;
+                                continue;
+                        }
+
+                        if (!found_monotonic)
+                                t->next_elapse_monotonic_or_boottime = v->next_elapse;
+                        else
+                                t->next_elapse_monotonic_or_boottime = MIN(t->next_elapse_monotonic_or_boottime, v->next_elapse);
+
+                        found_monotonic = true;
+                }
         }
 
-        if (!found) {
+        if (!found_monotonic && !found_realtime) {
+                log_unit_debug(UNIT(t)->id, "%s: Timer is elapsed.", UNIT(t)->id);
                 timer_set_state(t, TIMER_ELAPSED);
                 return;
         }
 
-        delay = n < t->next_elapse ? t->next_elapse - n : 0;
+        if (found_monotonic) {
+                char buf[FORMAT_TIMESPAN_MAX];
 
-        if ((r = unit_watch_timer(UNIT(t), delay, &t->timer_watch)) < 0)
-                goto fail;
+                log_unit_debug(UNIT(t)->id, "%s: Monotonic timer elapses in %s.",
+                               UNIT(t)->id,
+                               format_timespan(buf, sizeof(buf), t->next_elapse_monotonic_or_boottime > ts_monotonic ? t->next_elapse_monotonic_or_boottime - ts_monotonic : 0, 0));
+
+                if (t->monotonic_event_source) {
+                        r = sd_event_source_set_time(t->monotonic_event_source, t->next_elapse_monotonic_or_boottime);
+                        if (r < 0)
+                                goto fail;
+
+                        r = sd_event_source_set_enabled(t->monotonic_event_source, SD_EVENT_ONESHOT);
+                } else
+                        r = sd_event_add_time(
+                                        UNIT(t)->manager->event,
+                                        &t->monotonic_event_source,
+                                        t->wake_system ? CLOCK_BOOTTIME_ALARM : CLOCK_MONOTONIC,
+                                        t->next_elapse_monotonic_or_boottime, t->accuracy_usec,
+                                        timer_dispatch, t);
+                if (r < 0)
+                        goto fail;
+
+        } else if (t->monotonic_event_source) {
+
+                r = sd_event_source_set_enabled(t->monotonic_event_source, SD_EVENT_OFF);
+                if (r < 0)
+                        goto fail;
+        }
+
+        if (found_realtime) {
+                char buf[FORMAT_TIMESTAMP_MAX];
+                log_unit_debug(UNIT(t)->id, "%s: Realtime timer elapses at %s.", UNIT(t)->id, format_timestamp(buf, sizeof(buf), t->next_elapse_realtime));
+
+                if (t->realtime_event_source) {
+                        r = sd_event_source_set_time(t->realtime_event_source, t->next_elapse_realtime);
+                        if (r < 0)
+                                goto fail;
+
+                        r = sd_event_source_set_enabled(t->realtime_event_source, SD_EVENT_ONESHOT);
+                } else
+                        r = sd_event_add_time(
+                                        UNIT(t)->manager->event,
+                                        &t->realtime_event_source,
+                                        t->wake_system ? CLOCK_REALTIME_ALARM : CLOCK_REALTIME,
+                                        t->next_elapse_realtime, t->accuracy_usec,
+                                        timer_dispatch, t);
+                if (r < 0)
+                        goto fail;
+
+        } else if (t->realtime_event_source) {
+
+                r = sd_event_source_set_enabled(t->realtime_event_source, SD_EVENT_OFF);
+                if (r < 0)
+                        goto fail;
+        }
 
         timer_set_state(t, TIMER_WAITING);
         return;
 
 fail:
-        log_warning("%s failed to enter waiting state: %s", UNIT(t)->id, strerror(-r));
+        log_unit_warning_errno(UNIT(t)->id, r, "%s failed to enter waiting state: %m", UNIT(t)->id);
         timer_enter_dead(t, TIMER_FAILURE_RESOURCES);
 }
 
 static void timer_enter_running(Timer *t) {
-        DBusError error;
+        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
         int r;
 
         assert(t);
-        dbus_error_init(&error);
 
         /* Don't start job if we are supposed to go down */
-        if (UNIT(t)->job && UNIT(t)->job->type == JOB_STOP)
+        if (unit_stop_pending(UNIT(t)))
                 return;
 
-        if ((r = manager_add_job(UNIT(t)->manager, JOB_START, UNIT_DEREF(t->unit), JOB_REPLACE, true, &error, NULL)) < 0)
+        r = manager_add_job(UNIT(t)->manager, JOB_START, UNIT_TRIGGER(UNIT(t)),
+                            JOB_REPLACE, true, &error, NULL);
+        if (r < 0)
                 goto fail;
 
+        dual_timestamp_get(&t->last_trigger);
+
+        if (t->stamp_path)
+                touch_file(t->stamp_path, true, t->last_trigger.realtime, UID_INVALID, GID_INVALID, 0);
+
         timer_set_state(t, TIMER_RUNNING);
         return;
 
 fail:
-        log_warning("%s failed to queue unit startup job: %s", UNIT(t)->id, bus_error(&error, r));
+        log_unit_warning(UNIT(t)->id,
+                         "%s failed to queue unit startup job: %s",
+                         UNIT(t)->id, bus_error_message(&error, r));
         timer_enter_dead(t, TIMER_FAILURE_RESOURCES);
-
-        dbus_error_free(&error);
 }
 
 static int timer_start(Unit *u) {
         Timer *t = TIMER(u);
+        TimerValue *v;
 
         assert(t);
         assert(t->state == TIMER_DEAD || t->state == TIMER_FAILED);
 
-        if (UNIT_DEREF(t->unit)->load_state != UNIT_LOADED)
+        if (UNIT_TRIGGER(u)->load_state != UNIT_LOADED)
                 return -ENOENT;
 
+        t->last_trigger = DUAL_TIMESTAMP_NULL;
+
+        /* Reenable all timers that depend on unit activation time */
+        LIST_FOREACH(value, v, t->values)
+                if (v->base == TIMER_ACTIVE)
+                        v->disabled = false;
+
+        if (t->stamp_path) {
+                struct stat st;
+
+                if (stat(t->stamp_path, &st) >= 0)
+                        t->last_trigger.realtime = timespec_load(&st.st_atim);
+                else if (errno == ENOENT)
+                        /* The timer has never run before,
+                         * make sure a stamp file exists.
+                         */
+                        touch_file(t->stamp_path, true, USEC_INFINITY, UID_INVALID, GID_INVALID, 0);
+        }
+
         t->result = TIMER_SUCCESS;
         timer_enter_waiting(t, true);
-        return 0;
+        return 1;
 }
 
 static int timer_stop(Unit *u) {
@@ -323,7 +557,7 @@ static int timer_stop(Unit *u) {
         assert(t->state == TIMER_WAITING || t->state == TIMER_RUNNING || t->state == TIMER_ELAPSED);
 
         timer_enter_dead(t, TIMER_SUCCESS);
-        return 0;
+        return 1;
 }
 
 static int timer_serialize(Unit *u, FILE *f, FDSet *fds) {
@@ -336,11 +570,18 @@ static int timer_serialize(Unit *u, FILE *f, FDSet *fds) {
         unit_serialize_item(u, f, "state", timer_state_to_string(t->state));
         unit_serialize_item(u, f, "result", timer_result_to_string(t->result));
 
+        if (t->last_trigger.realtime > 0)
+                unit_serialize_item_format(u, f, "last-trigger-realtime", "%" PRIu64, t->last_trigger.realtime);
+
+        if (t->last_trigger.monotonic > 0)
+                unit_serialize_item_format(u, f, "last-trigger-monotonic", "%" PRIu64, t->last_trigger.monotonic);
+
         return 0;
 }
 
 static int timer_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
         Timer *t = TIMER(u);
+        int r;
 
         assert(u);
         assert(key);
@@ -350,8 +591,9 @@ static int timer_deserialize_item(Unit *u, const char *key, const char *value, F
         if (streq(key, "state")) {
                 TimerState state;
 
-                if ((state = timer_state_from_string(value)) < 0)
-                        log_debug("Failed to parse state value %s", value);
+                state = timer_state_from_string(value);
+                if (state < 0)
+                        log_unit_debug(u->id, "Failed to parse state value %s", value);
                 else
                         t->deserialized_state = state;
         } else if (streq(key, "result")) {
@@ -359,91 +601,91 @@ static int timer_deserialize_item(Unit *u, const char *key, const char *value, F
 
                 f = timer_result_from_string(value);
                 if (f < 0)
-                        log_debug("Failed to parse result value %s", value);
+                        log_unit_debug(u->id, "Failed to parse result value %s", value);
                 else if (f != TIMER_SUCCESS)
                         t->result = f;
+        } else if (streq(key, "last-trigger-realtime")) {
+
+                r = safe_atou64(value, &t->last_trigger.realtime);
+                if (r < 0)
+                        log_unit_debug(u->id, "Failed to parse last-trigger-realtime value %s", value);
+
+        } else if (streq(key, "last-trigger-monotonic")) {
+
+                r = safe_atou64(value, &t->last_trigger.monotonic);
+                if (r < 0)
+                        log_unit_debug(u->id, "Failed to parse last-trigger-monotonic value %s", value);
 
         } else
-                log_debug("Unknown serialization key '%s'", key);
+                log_unit_debug(u->id, "Unknown serialization key '%s'", key);
 
         return 0;
 }
 
-static UnitActiveState timer_active_state(Unit *u) {
+_pure_ static UnitActiveState timer_active_state(Unit *u) {
         assert(u);
 
         return state_translation_table[TIMER(u)->state];
 }
 
-static const char *timer_sub_state_to_string(Unit *u) {
+_pure_ static const char *timer_sub_state_to_string(Unit *u) {
         assert(u);
 
         return timer_state_to_string(TIMER(u)->state);
 }
 
-static void timer_timer_event(Unit *u, uint64_t elapsed, Watch *w) {
-        Timer *t = TIMER(u);
+static int timer_dispatch(sd_event_source *s, uint64_t usec, void *userdata) {
+        Timer *t = TIMER(userdata);
 
         assert(t);
-        assert(elapsed == 1);
 
         if (t->state != TIMER_WAITING)
-                return;
+                return 0;
 
-        log_debug("Timer elapsed on %s", u->id);
+        log_unit_debug(UNIT(t)->id, "Timer elapsed on %s", UNIT(t)->id);
         timer_enter_running(t);
+        return 0;
 }
 
-void timer_unit_notify(Unit *u, UnitActiveState new_state) {
-        Iterator i;
-        Unit *k;
-
-        if (u->type == UNIT_TIMER)
-                return;
+static void timer_trigger_notify(Unit *u, Unit *other) {
+        Timer *t = TIMER(u);
+        TimerValue *v;
 
-        SET_FOREACH(k, u->dependencies[UNIT_TRIGGERED_BY], i) {
-                Timer *t;
-                TimerValue *v;
+        assert(u);
+        assert(other);
 
-                if (k->type != UNIT_TIMER)
-                        continue;
+        if (other->load_state != UNIT_LOADED)
+                return;
 
-                if (k->load_state != UNIT_LOADED)
-                        continue;
+        /* Reenable all timers that depend on unit state */
+        LIST_FOREACH(value, v, t->values)
+                if (v->base == TIMER_UNIT_ACTIVE ||
+                    v->base == TIMER_UNIT_INACTIVE)
+                        v->disabled = false;
 
-                t = TIMER(k);
+        switch (t->state) {
 
-                /* Reenable all timers that depend on unit state */
-                LIST_FOREACH(value, v, t->values)
-                        if (v->base == TIMER_UNIT_ACTIVE ||
-                            v->base == TIMER_UNIT_INACTIVE)
-                                v->disabled = false;
+        case TIMER_WAITING:
+        case TIMER_ELAPSED:
 
-                switch (t->state) {
+                /* Recalculate sleep time */
+                timer_enter_waiting(t, false);
+                break;
 
-                case TIMER_WAITING:
-                case TIMER_ELAPSED:
+        case TIMER_RUNNING:
 
-                        /* Recalculate sleep time */
+                if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(other))) {
+                        log_unit_debug(UNIT(t)->id, "%s got notified about unit deactivation.", UNIT(t)->id);
                         timer_enter_waiting(t, false);
-                        break;
-
-                case TIMER_RUNNING:
-
-                        if (UNIT_IS_INACTIVE_OR_FAILED(new_state)) {
-                                log_debug("%s got notified about unit deactivation.", UNIT(t)->id);
-                                timer_enter_waiting(t, false);
-                        }
-
-                        break;
+                }
+                break;
 
-                case TIMER_DEAD:
-                case TIMER_FAILED:
-                        break;
+        case TIMER_DEAD:
+        case TIMER_FAILED:
+                break;
 
-                default:
-                        assert_not_reached("Unknown timer state");
-                }
+        default:
+                assert_not_reached("Unknown timer state");
         }
 }
 
@@ -458,6 +700,18 @@ static void timer_reset_failed(Unit *u) {
         t->result = TIMER_SUCCESS;
 }
 
+static void timer_time_change(Unit *u) {
+        Timer *t = TIMER(u);
+
+        assert(u);
+
+        if (t->state != TIMER_WAITING)
+                return;
+
+        log_unit_debug(u->id, "%s: time change, recalculating next elapse.", u->id);
+        timer_enter_waiting(t, false);
+}
+
 static const char* const timer_state_table[_TIMER_STATE_MAX] = {
         [TIMER_DEAD] = "dead",
         [TIMER_WAITING] = "waiting",
@@ -473,7 +727,8 @@ static const char* const timer_base_table[_TIMER_BASE_MAX] = {
         [TIMER_BOOT] = "OnBootSec",
         [TIMER_STARTUP] = "OnStartupSec",
         [TIMER_UNIT_ACTIVE] = "OnUnitActiveSec",
-        [TIMER_UNIT_INACTIVE] = "OnUnitInactiveSec"
+        [TIMER_UNIT_INACTIVE] = "OnUnitInactiveSec",
+        [TIMER_CALENDAR] = "OnCalendar"
 };
 
 DEFINE_STRING_TABLE_LOOKUP(timer_base, TimerBase);
@@ -486,12 +741,13 @@ static const char* const timer_result_table[_TIMER_RESULT_MAX] = {
 DEFINE_STRING_TABLE_LOOKUP(timer_result, TimerResult);
 
 const UnitVTable timer_vtable = {
-        .suffix = ".timer",
         .object_size = sizeof(Timer),
+
         .sections =
                 "Unit\0"
                 "Timer\0"
                 "Install\0",
+        .private_section = "Timer",
 
         .init = timer_init,
         .done = timer_done,
@@ -510,11 +766,14 @@ const UnitVTable timer_vtable = {
         .active_state = timer_active_state,
         .sub_state_to_string = timer_sub_state_to_string,
 
-        .timer_event = timer_timer_event,
+        .trigger_notify = timer_trigger_notify,
 
         .reset_failed = timer_reset_failed,
+        .time_change = timer_time_change,
 
         .bus_interface = "org.freedesktop.systemd1.Timer",
-        .bus_message_handler = bus_timer_message_handler,
-        .bus_invalidating_properties =  bus_timer_invalidating_properties
+        .bus_vtable = bus_timer_vtable,
+        .bus_set_property = bus_timer_set_property,
+
+        .can_transient = true,
 };