systemctl: port "systemctl start --wait" logic to new bus-wait-for-units.c API

1 files changed, 15 insertions, 171 deletions

diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index 616ac0f5d4..7b39f5d95b 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -2793,158 +2793,6 @@ static const char *verb_to_job_type(const char *verb) {
        return "start";
 }
 
-typedef struct {
-        sd_bus_slot *match;
-        sd_event *event;
-        Set *unit_paths;
-        bool any_failed;
-} WaitContext;
-
-static void wait_context_free(WaitContext *c) {
-        c->match = sd_bus_slot_unref(c->match);
-        c->event = sd_event_unref(c->event);
-        c->unit_paths = set_free_free(c->unit_paths);
-}
-
-static int on_properties_changed(sd_bus_message *m, void *userdata, sd_bus_error *error) {
-        const char *path, *interface, *active_state = NULL, *job_path = NULL;
-        WaitContext *c = userdata;
-        bool is_failed;
-        int r;
-
-        /* Called whenever we get a PropertiesChanged signal. Checks if ActiveState changed to inactive/failed.
-         *
-         * Signal parameters: (s interface, a{sv} changed_properties, as invalidated_properties) */
-
-        path = sd_bus_message_get_path(m);
-        if (!set_contains(c->unit_paths, path))
-                return 0;
-
-        r = sd_bus_message_read(m, "s", &interface);
-        if (r < 0)
-                return bus_log_parse_error(r);
-
-        if (!streq(interface, "org.freedesktop.systemd1.Unit")) /* ActiveState is on the Unit interface */
-                return 0;
-
-        r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, "{sv}");
-        if (r < 0)
-                return bus_log_parse_error(r);
-
-        for (;;) {
-                const char *s;
-
-                r = sd_bus_message_enter_container(m, SD_BUS_TYPE_DICT_ENTRY, "sv");
-                if (r < 0)
-                        return bus_log_parse_error(r);
-                if (r == 0) /* end of array */
-                        break;
-
-                r = sd_bus_message_read(m, "s", &s); /* Property name */
-                if (r < 0)
-                        return bus_log_parse_error(r);
-
-                if (streq(s, "ActiveState")) {
-                        r = sd_bus_message_read(m, "v", "s", &active_state);
-                        if (r < 0)
-                                return bus_log_parse_error(r);
-
-                        if (job_path) /* Found everything we need */
-                                break;
-
-                } else if (streq(s, "Job")) {
-                        uint32_t job_id;
-
-                        r = sd_bus_message_read(m, "v", "(uo)", &job_id, &job_path);
-                        if (r < 0)
-                                return bus_log_parse_error(r);
-
-                        /* There's still a job pending for this unit, let's ignore this for now, and return right-away. */
-                        if (job_id != 0)
-                                return 0;
-
-                        if (active_state) /* Found everything we need */
-                                break;
-
-                } else {
-                        r = sd_bus_message_skip(m, "v"); /* Other property */
-                        if (r < 0)
-                                return bus_log_parse_error(r);
-                }
-
-                r = sd_bus_message_exit_container(m);
-                if (r < 0)
-                        return bus_log_parse_error(r);
-        }
-
-        /* If this didn't contain the ActiveState property we can't do anything */
-        if (!active_state)
-                return 0;
-
-        is_failed = streq(active_state, "failed");
-        if (streq(active_state, "inactive") || is_failed) {
-                log_debug("%s became %s, dropping from --wait tracking", path, active_state);
-                free(set_remove(c->unit_paths, path));
-                c->any_failed = c->any_failed || is_failed;
-        } else
-                log_debug("ActiveState on %s changed to %s", path, active_state);
-
-        if (set_isempty(c->unit_paths))
-                sd_event_exit(c->event, EXIT_SUCCESS);
-
-        return 0;
-}
-
-static int wait_context_watch(
-                WaitContext *wait_context,
-                sd_bus *bus,
-                const char *name) {
-
-        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_free_ char *unit_path = NULL;
-        int r;
-
-        assert(wait_context);
-        assert(name);
-
-        log_debug("Watching for property changes of %s", name);
-        r = sd_bus_call_method(
-                        bus,
-                        "org.freedesktop.systemd1",
-                        "/org/freedesktop/systemd1",
-                        "org.freedesktop.systemd1.Manager",
-                        "RefUnit",
-                        &error,
-                        NULL,
-                        "s", name);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add reference to unit %s: %s", name, bus_error_message(&error, r));
-
-        unit_path = unit_dbus_path_from_name(name);
-        if (!unit_path)
-                return log_oom();
-
-        r = set_ensure_allocated(&wait_context->unit_paths, &string_hash_ops);
-        if (r < 0)
-                return log_oom();
-
-        r = set_put_strdup(wait_context->unit_paths, unit_path);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add unit path %s to set: %m", unit_path);
-
-        r = sd_bus_match_signal_async(bus,
-                                      &wait_context->match,
-                                      NULL,
-                                      unit_path,
-                                      "org.freedesktop.DBus.Properties",
-                                      "PropertiesChanged",
-                                      on_properties_changed, NULL, wait_context);
-        if (r < 0)
-                return log_error_errno(r, "Failed to request match for PropertiesChanged signal: %m");
-
-        return 0;
-}
-
 static int start_unit_one(
                 sd_bus *bus,
                 const char *method,    /* When using classic per-job bus methods */
@@ -2953,7 +2801,7 @@ static int start_unit_one(
                 const char *mode,
                 sd_bus_error *error,
                 BusWaitForJobs *w,
-                WaitContext *wait_context) {
+                BusWaitForUnits *wu) {
 
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         const char *path;
@@ -2965,12 +2813,6 @@ static int start_unit_one(
         assert(mode);
         assert(error);
 
-        if (wait_context) {
-                r = wait_context_watch(wait_context, bus, name);
-                if (r < 0)
-                        return r;
-        }
-
         log_debug("%s dbus call org.freedesktop.systemd1.Manager %s(%s, %s)",
                   arg_dry_run ? "Would execute" : "Executing",
                   method, name, mode);
@@ -3059,6 +2901,12 @@ static int start_unit_one(
                         return log_error_errno(r, "Failed to watch job for %s: %m", name);
         }
 
+        if (wu) {
+                r = bus_wait_for_units_add_unit(wu, name, BUS_WAIT_FOR_INACTIVE|BUS_WAIT_NO_JOB, NULL, NULL);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to watch unit %s: %m", name);
+        }
+
         return 0;
 
 fail:
@@ -3190,8 +3038,8 @@ static const char** make_extra_args(const char *extra_args[static 4]) {
 }
 
 static int start_unit(int argc, char *argv[], void *userdata) {
+        _cleanup_(bus_wait_for_units_freep) BusWaitForUnits *wu = NULL;
         _cleanup_(bus_wait_for_jobs_freep) BusWaitForJobs *w = NULL;
-        _cleanup_(wait_context_free) WaitContext wait_context = {};
         const char *method, *job_type, *mode, *one_name, *suffix = NULL;
         _cleanup_free_ char **stopped_units = NULL; /* Do not use _cleanup_strv_free_ */
         _cleanup_strv_free_ char **names = NULL;
@@ -3279,19 +3127,15 @@ static int start_unit(int argc, char *argv[], void *userdata) {
                 if (r < 0)
                         return log_error_errno(r, "Failed to enable subscription: %m");
 
-                r = sd_event_default(&wait_context.event);
+                r = bus_wait_for_units_new(bus, &wu);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to allocate event loop: %m");
-
-                r = sd_bus_attach_event(bus, wait_context.event, 0);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to attach bus to event loop: %m");
+                        return log_error_errno(r, "Failed to allocate unit watch context: %m");
         }
 
         STRV_FOREACH(name, names) {
                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 
-                r = start_unit_one(bus, method, job_type, *name, mode, &error, w, arg_wait ? &wait_context : NULL);
+                r = start_unit_one(bus, method, job_type, *name, mode, &error, w, wu);
                 if (ret == EXIT_SUCCESS && r < 0)
                         ret = translate_bus_error_to_exit_status(r, &error);
 
@@ -3316,11 +3160,11 @@ static int start_unit(int argc, char *argv[], void *userdata) {
                                 (void) check_triggering_units(bus, *name);
         }
 
-        if (ret == EXIT_SUCCESS && arg_wait && !set_isempty(wait_context.unit_paths)) {
-                r = sd_event_loop(wait_context.event);
+        if (arg_wait) {
+                r = bus_wait_for_units_run(wu);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to run event loop: %m");
-                if (wait_context.any_failed)
+                        return log_error_errno(r, "Failed to wait for units: %m");
+                if (r == BUS_WAIT_FAILURE && ret == EXIT_SUCCESS)
                         ret = EXIT_FAILURE;
         }