/* SPDX-License-Identifier: LGPL-2.1+ */
#include "bus-util.h"
#include "bus-wait-for-units.h"
#include "hashmap.h"
#include "string-util.h"
#include "strv.h"
#include "unit-def.h"
typedef struct WaitForItem {
BusWaitForUnits *parent;
BusWaitForUnitsFlags flags;
char *bus_path;
sd_bus_slot *slot_get_all;
sd_bus_slot *slot_properties_changed;
bus_wait_for_units_unit_callback unit_callback;
void *userdata;
char *active_state;
uint32_t job_id;
char *clean_result;
} WaitForItem;
typedef struct BusWaitForUnits {
sd_bus *bus;
sd_bus_slot *slot_disconnected;
Hashmap *items;
bus_wait_for_units_ready_callback ready_callback;
void *userdata;
WaitForItem *current;
BusWaitForUnitsState state;
bool has_failed:1;
} BusWaitForUnits;
static WaitForItem *wait_for_item_free(WaitForItem *item) {
int r;
if (!item)
return NULL;
if (item->parent) {
if (FLAGS_SET(item->flags, BUS_WAIT_REFFED) && item->bus_path && item->parent->bus) {
r = sd_bus_call_method_async(
item->parent->bus,
NULL,
"org.freedesktop.systemd1",
item->bus_path,
"org.freedesktop.systemd1.Unit",
"Unref",
NULL,
NULL,
NULL);
if (r < 0)
log_debug_errno(r, "Failed to drop reference to unit %s, ignoring: %m", item->bus_path);
}
assert_se(hashmap_remove(item->parent->items, item->bus_path) == item);
if (item->parent->current == item)
item->parent->current = NULL;
}
sd_bus_slot_unref(item->slot_properties_changed);
sd_bus_slot_unref(item->slot_get_all);
free(item->bus_path);
free(item->active_state);
free(item->clean_result);
return mfree(item);
}
DEFINE_TRIVIAL_CLEANUP_FUNC(WaitForItem*, wait_for_item_free);
static void call_unit_callback_and_wait(BusWaitForUnits *d, WaitForItem *item, bool good) {
d->current = item;
if (item->unit_callback)
item->unit_callback(d, item->bus_path, good, item->userdata);
wait_for_item_free(item);
}
static void bus_wait_for_units_clear(BusWaitForUnits *d) {
WaitForItem *item;
assert(d);
d->slot_disconnected = sd_bus_slot_unref(d->slot_disconnected);
d->bus = sd_bus_unref(d->bus);
while ((item = hashmap_first(d->items)))
call_unit_callback_and_wait(d, item, false);
d->items = hashmap_free(d->items);
}
static int match_disconnected(sd_bus_message *m, void *userdata, sd_bus_error *error) {
BusWaitForUnits *d = userdata;
assert(m);
assert(d);
log_error("Warning! D-Bus connection terminated.");
bus_wait_for_units_clear(d);
if (d->ready_callback)
d->ready_callback(d, false, d->userdata);
else /* If no ready callback is specified close the connection so that the event loop exits */
sd_bus_close(sd_bus_message_get_bus(m));
return 0;
}
int bus_wait_for_units_new(sd_bus *bus, BusWaitForUnits **ret) {
_cleanup_(bus_wait_for_units_freep) BusWaitForUnits *d = NULL;
int r;
assert(bus);
assert(ret);
d = new(BusWaitForUnits, 1);
if (!d)
return -ENOMEM;
*d = (BusWaitForUnits) {
.state = BUS_WAIT_SUCCESS,
.bus = sd_bus_ref(bus),
};
r = sd_bus_match_signal_async(
bus,
&d->slot_disconnected,
"org.freedesktop.DBus.Local",
NULL,
"org.freedesktop.DBus.Local",
"Disconnected",
match_disconnected, NULL, d);
if (r < 0)
return r;
*ret = TAKE_PTR(d);
return 0;
}
BusWaitForUnits* bus_wait_for_units_free(BusWaitForUnits *d) {
if (!d)
return NULL;
bus_wait_for_units_clear(d);
sd_bus_slot_unref(d->slot_disconnected);
sd_bus_unref(d->bus);
return mfree(d);
}
static bool bus_wait_for_units_is_ready(BusWaitForUnits *d) {
assert(d);
if (!d->bus) /* Disconnected? */
return true;
return hashmap_isempty(d->items);
}
void bus_wait_for_units_set_ready_callback(BusWaitForUnits *d, bus_wait_for_units_ready_callback callback, void *userdata) {
assert(d);
d->ready_callback = callback;
d->userdata = userdata;
}
static void bus_wait_for_units_check_ready(BusWaitForUnits *d) {
assert(d);
if (!bus_wait_for_units_is_ready(d))
return;
d->state = d->has_failed ? BUS_WAIT_FAILURE : BUS_WAIT_SUCCESS;
if (d->ready_callback)
d->ready_callback(d, d->state, d->userdata);
}
static void wait_for_item_check_ready(WaitForItem *item) {
BusWaitForUnits *d;
assert(item);
assert_se(d = item->parent);
if (FLAGS_SET(item->flags, BUS_WAIT_FOR_MAINTENANCE_END)) {
if (item->clean_result && !streq(item->clean_result, "success"))
d->has_failed = true;
if (!item->active_state || streq(item->active_state, "maintenance"))
return;
}
if (FLAGS_SET(item->flags, BUS_WAIT_NO_JOB) && item->job_id != 0)
return;
if (FLAGS_SET(item->flags, BUS_WAIT_FOR_INACTIVE)) {
if (streq_ptr(item->active_state, "failed"))
d->has_failed = true;
else if (!streq_ptr(item->active_state, "inactive"))
return;
}
call_unit_callback_and_wait(d, item, true);
bus_wait_for_units_check_ready(d);
}
static int property_map_job(
sd_bus *bus,
const char *member,
sd_bus_message *m,
sd_bus_error *error,
void *userdata) {
WaitForItem *item = userdata;
const char *path;
uint32_t id;
int r;
assert(item);
r = sd_bus_message_read(m, "(uo)", &id, &path);
if (r < 0)
return r;
item->job_id = id;
return 0;
}
static int wait_for_item_parse_properties(WaitForItem *item, sd_bus_message *m) {
static const struct bus_properties_map map[] = {
{ "ActiveState", "s", NULL, offsetof(WaitForItem, active_state) },
{ "Job", "(uo)", property_map_job, 0 },
{ "CleanResult", "s", NULL, offsetof(WaitForItem, clean_result) },
{}
};
int r;
assert(item);
assert(m);
r = bus_message_map_all_properties(m, map, BUS_MAP_STRDUP, NULL, item);
if (r < 0)
return r;
wait_for_item_check_ready(item);
return 0;
}
static int on_properties_changed(sd_bus_message *m, void *userdata, sd_bus_error *error) {
WaitForItem *item = userdata;
const char *interface;
int r;
assert(item);
r = sd_bus_message_read(m, "s", &interface);
if (r < 0) {
log_debug_errno(r, "Failed to parse PropertiesChanged signal: %m");
return 0;
}
if (!streq(interface, "org.freedesktop.systemd1.Unit"))
return 0;
r = wait_for_item_parse_properties(item, m);
if (r < 0)
log_debug_errno(r, "Failed to process PropertiesChanged signal: %m");
return 0;
}
static int on_get_all_properties(sd_bus_message *m, void *userdata, sd_bus_error *error) {
WaitForItem *item = userdata;
int r;
assert(item);
if (sd_bus_error_is_set(error)) {
BusWaitForUnits *d = item->parent;
d->has_failed = true;
log_debug_errno(sd_bus_error_get_errno(error), "GetAll() failed for %s: %s",
item->bus_path, error->message);
call_unit_callback_and_wait(d, item, false);
bus_wait_for_units_check_ready(d);
return 0;
}
r = wait_for_item_parse_properties(item, m);
if (r < 0)
log_debug_errno(r, "Failed to process GetAll method reply: %m");
return 0;
}
int bus_wait_for_units_add_unit(
BusWaitForUnits *d,
const char *unit,
BusWaitForUnitsFlags flags,
bus_wait_for_units_unit_callback callback,
void *userdata) {
_cleanup_(wait_for_item_freep) WaitForItem *item = NULL;
int r;
assert(d);
assert(unit);
assert(flags != 0);
r = hashmap_ensure_allocated(&d->items, &string_hash_ops);
if (r < 0)
return r;
item = new(WaitForItem, 1);
if (!item)
return -ENOMEM;
*item = (WaitForItem) {
.flags = flags,
.bus_path = unit_dbus_path_from_name(unit),
.unit_callback = callback,
.userdata = userdata,
.job_id = UINT32_MAX,
};
if (!item->bus_path)
return -ENOMEM;
if (!FLAGS_SET(item->flags, BUS_WAIT_REFFED)) {
r = sd_bus_call_method_async(
d->bus,
NULL,
"org.freedesktop.systemd1",
item->bus_path,
"org.freedesktop.systemd1.Unit",
"Ref",
NULL,
NULL,
NULL);
if (r < 0)
return log_debug_errno(r, "Failed to add reference to unit %s: %m", unit);
item->flags |= BUS_WAIT_REFFED;
}
r = sd_bus_match_signal_async(
d->bus,
&item->slot_properties_changed,
"org.freedesktop.systemd1",
item->bus_path,
"org.freedesktop.DBus.Properties",
"PropertiesChanged",
on_properties_changed,
NULL,
item);
if (r < 0)
return log_debug_errno(r, "Failed to request match for PropertiesChanged signal: %m");
r = sd_bus_call_method_async(
d->bus,
&item->slot_get_all,
"org.freedesktop.systemd1",
item->bus_path,
"org.freedesktop.DBus.Properties",
"GetAll",
on_get_all_properties,
item,
"s", FLAGS_SET(item->flags, BUS_WAIT_FOR_MAINTENANCE_END) ? NULL : "org.freedesktop.systemd1.Unit");
if (r < 0)
return log_debug_errno(r, "Failed to request properties of unit %s: %m", unit);
r = hashmap_put(d->items, item->bus_path, item);
if (r < 0)
return r;
d->state = BUS_WAIT_RUNNING;
item->parent = d;
TAKE_PTR(item);
return 0;
}
int bus_wait_for_units_run(BusWaitForUnits *d) {
int r;
assert(d);
while (d->state == BUS_WAIT_RUNNING) {
r = sd_bus_process(d->bus, NULL);
if (r < 0)
return r;
if (r > 0)
continue;
r = sd_bus_wait(d->bus, (uint64_t) -1);
if (r < 0)
return r;
}
return d->state;
}
BusWaitForUnitsState bus_wait_for_units_state(BusWaitForUnits *d) {
assert(d);
return d->state;
}