core: convert PID 1 to libsystemd-bus

This patch converts PID 1 to libsystemd-bus and thus drops the
dependency on libdbus. The only remaining code using libdbus is a test
case that validates our bus marshalling against libdbus' marshalling,
and this dependency can be turned off.

This patch also adds a couple of things to libsystem-bus, that are
necessary to make the port work:

- Synthesizing of "Disconnected" messages when bus connections are
  severed.

- Support for attaching multiple vtables for the same interface on the
  same path.

This patch also fixes the SetDefaultTarget() and GetDefaultTarget() bus
calls which used an inappropriate signature.

As a side effect we will now generate PropertiesChanged messages which
carry property contents, rather than just invalidation information.

1 files changed, 44 insertions, 26 deletions

diff --git a/src/core/scope.c b/src/core/scope.c
index 41da3b9378..a3c94794b1 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -40,6 +40,8 @@ static const UnitActiveState state_translation_table[_SCOPE_STATE_MAX] = {
         [SCOPE_FAILED] = UNIT_FAILED
 };
 
+static int scope_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata);
+
 static void scope_init(Unit *u) {
         Scope *s = SCOPE(u);
 
@@ -48,8 +50,6 @@ static void scope_init(Unit *u) {
 
         s->timeout_stop_usec = u->manager->default_timeout_stop_usec;
 
-        watch_init(&s->timer_watch);
-
         cgroup_context_init(&s->cgroup_context);
         kill_context_init(&s->kill_context);
 
@@ -67,7 +67,28 @@ static void scope_done(Unit *u) {
         set_free(s->pids);
         s->pids = NULL;
 
-        unit_unwatch_timer(u, &s->timer_watch);
+        s->timer_event_source = sd_event_source_unref(s->timer_event_source);
+}
+
+static int scope_arm_timer(Scope *s) {
+        int r;
+
+        assert(s);
+
+        if (s->timeout_stop_usec <= 0) {
+                s->timer_event_source = sd_event_source_unref(s->timer_event_source);
+                return 0;
+        }
+
+        if (s->timer_event_source) {
+                r = sd_event_source_set_time(s->timer_event_source, now(CLOCK_MONOTONIC) + s->timeout_stop_usec);
+                if (r < 0)
+                        return r;
+
+                return sd_event_source_set_enabled(s->timer_event_source, SD_EVENT_ONESHOT);
+        }
+
+        return sd_event_add_monotonic(UNIT(s)->manager->event, now(CLOCK_MONOTONIC) + s->timeout_stop_usec, 0, scope_dispatch_timer, s, &s->timer_event_source);
 }
 
 static void scope_set_state(Scope *s, ScopeState state) {
@@ -79,7 +100,7 @@ static void scope_set_state(Scope *s, ScopeState state) {
 
         if (state != SCOPE_STOP_SIGTERM &&
             state != SCOPE_STOP_SIGKILL)
-                unit_unwatch_timer(UNIT(s), &s->timer_watch);
+                s->timer_event_source = sd_event_source_unref(s->timer_event_source);
 
         if (state != old_state)
                 log_debug("%s changed %s -> %s",
@@ -158,11 +179,9 @@ static int scope_coldplug(Unit *u) {
 
         if (s->deserialized_state != s->state) {
 
-                if ((s->deserialized_state == SCOPE_STOP_SIGKILL || s->deserialized_state == SCOPE_STOP_SIGTERM)
-                    && s->timeout_stop_usec > 0) {
-                        r = unit_watch_timer(UNIT(s), CLOCK_MONOTONIC, true, s->timeout_stop_usec, &s->timer_watch);
+                if (s->deserialized_state == SCOPE_STOP_SIGKILL || s->deserialized_state == SCOPE_STOP_SIGTERM) {
+                        r = scope_arm_timer(s);
                         if (r < 0)
-
                                 return r;
                 }
 
@@ -214,11 +233,9 @@ static void scope_enter_signal(Scope *s, ScopeState state, ScopeResult f) {
                 goto fail;
 
         if (r > 0) {
-                if (s->timeout_stop_usec > 0) {
-                        r = unit_watch_timer(UNIT(s), CLOCK_MONOTONIC, true, s->timeout_stop_usec, &s->timer_watch);
-                        if (r < 0)
-                                goto fail;
-                }
+                r = scope_arm_timer(s);
+                if (r < 0)
+                        goto fail;
 
                 scope_set_state(s, state);
         } else
@@ -297,7 +314,7 @@ static void scope_reset_failed(Unit *u) {
         s->result = SCOPE_SUCCESS;
 }
 
-static int scope_kill(Unit *u, KillWho who, int signo, DBusError *error) {
+static int scope_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) {
         return unit_kill_common(u, who, signo, -1, -1, error);
 }
 
@@ -353,34 +370,35 @@ static bool scope_check_gc(Unit *u) {
         return false;
 }
 
-static void scope_timer_event(Unit *u, uint64_t elapsed, Watch*w) {
-        Scope *s = SCOPE(u);
+static int scope_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) {
+        Scope *s = SCOPE(userdata);
 
         assert(s);
-        assert(elapsed == 1);
-        assert(w == &s->timer_watch);
+        assert(s->timer_event_source == source);
 
         switch (s->state) {
 
         case SCOPE_STOP_SIGTERM:
                 if (s->kill_context.send_sigkill) {
-                        log_warning_unit(u->id, "%s stopping timed out. Killing.", u->id);
+                        log_warning_unit(UNIT(s)->id, "%s stopping timed out. Killing.", UNIT(s)->id);
                         scope_enter_signal(s, SCOPE_STOP_SIGKILL, SCOPE_FAILURE_TIMEOUT);
                 } else {
-                        log_warning_unit(u->id, "%s stopping timed out. Skipping SIGKILL.", u->id);
+                        log_warning_unit(UNIT(s)->id, "%s stopping timed out. Skipping SIGKILL.", UNIT(s)->id);
                         scope_enter_dead(s, SCOPE_FAILURE_TIMEOUT);
                 }
 
                 break;
 
         case SCOPE_STOP_SIGKILL:
-                log_warning_unit(u->id, "%s still around after SIGKILL. Ignoring.", u->id);
+                log_warning_unit(UNIT(s)->id, "%s still around after SIGKILL. Ignoring.", UNIT(s)->id);
                 scope_enter_dead(s, SCOPE_FAILURE_TIMEOUT);
                 break;
 
         default:
                 assert_not_reached("Timeout at wrong time.");
         }
+
+        return 0;
 }
 
 static void scope_notify_cgroup_empty_event(Unit *u) {
@@ -435,13 +453,14 @@ DEFINE_STRING_TABLE_LOOKUP(scope_result, ScopeResult);
 
 const UnitVTable scope_vtable = {
         .object_size = sizeof(Scope),
+        .cgroup_context_offset = offsetof(Scope, cgroup_context),
+        .kill_context_offset = offsetof(Scope, kill_context),
+
         .sections =
                 "Unit\0"
                 "Scope\0"
                 "Install\0",
-
         .private_section = "Scope",
-        .cgroup_context_offset = offsetof(Scope, cgroup_context),
 
         .no_alias = true,
         .no_instances = true,
@@ -467,14 +486,13 @@ const UnitVTable scope_vtable = {
 
         .check_gc = scope_check_gc,
 
-        .timer_event = scope_timer_event,
-
         .reset_failed = scope_reset_failed,
 
         .notify_cgroup_empty = scope_notify_cgroup_empty_event,
 
         .bus_interface = "org.freedesktop.systemd1.Scope",
-        .bus_message_handler = bus_scope_message_handler,
+        .bus_vtable = bus_scope_vtable,
+        .bus_changing_properties = bus_scope_changing_properties,
         .bus_set_property = bus_scope_set_property,
         .bus_commit_properties = bus_scope_commit_properties,