Systemd/src/core/dbus-job.c
Lennart Poettering 8f8f05a919 bus: add sd_bus_track object for tracking peers, and port core over to it
This is primarily useful for services that need to track clients which
reference certain objects they maintain, or which explicitly want to
subscribe to certain events. Something like this is done in a large
number of services, and not trivial to do. Hence, let's unify this at
one place.

This also ports over PID 1 to use this to ensure that subscriptions to
job and manager events are correctly tracked. As a side-effect this
makes sure we properly serialize and restore the track list across
daemon reexec/reload, which didn't work correctly before.

This also simplifies how we distribute messages to broadcast to the
direct busses: we only track subscriptions for the API bus and
implicitly assume that all direct busses are subscribed. This should be
a pretty OK simplification since clients connected via direct bus
connections are shortlived anyway.
2014-03-03 02:34:13 +01:00

183 lines
5.3 KiB
C

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
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 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include "log.h"
#include "sd-bus.h"
#include "selinux-access.h"
#include "job.h"
#include "dbus-job.h"
#include "dbus.h"
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_type, job_type, JobType);
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_state, job_state, JobState);
static int property_get_unit(
sd_bus *bus,
const char *path,
const char *interface,
const char *property,
sd_bus_message *reply,
void *userdata,
sd_bus_error *error) {
_cleanup_free_ char *p = NULL;
Job *j = userdata;
assert(bus);
assert(reply);
assert(j);
p = unit_dbus_path(j->unit);
if (!p)
return -ENOMEM;
return sd_bus_message_append(reply, "(so)", j->unit->id, p);
}
static int method_cancel(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
Job *j = userdata;
int r;
assert(bus);
assert(message);
assert(j);
r = selinux_unit_access_check(j->unit, bus, message, "stop", error);
if (r < 0)
return r;
job_finish_and_invalidate(j, JOB_CANCELED, true);
return sd_bus_reply_method_return(message, NULL);
}
const sd_bus_vtable bus_job_vtable[] = {
SD_BUS_VTABLE_START(0),
SD_BUS_METHOD("Cancel", NULL, NULL, method_cancel, 0),
SD_BUS_PROPERTY("Id", "u", NULL, offsetof(Job, id), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("Unit", "(so)", property_get_unit, 0, SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("JobType", "s", property_get_type, offsetof(Job, type), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("State", "s", property_get_state, offsetof(Job, state), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
SD_BUS_VTABLE_END
};
static int send_new_signal(sd_bus *bus, void *userdata) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
_cleanup_free_ char *p = NULL;
Job *j = userdata;
int r;
assert(bus);
assert(j);
p = job_dbus_path(j);
if (!p)
return -ENOMEM;
r = sd_bus_message_new_signal(
bus,
&m,
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"JobNew");
if (r < 0)
return r;
r = sd_bus_message_append(m, "uos", j->id, p, j->unit->id);
if (r < 0)
return r;
return sd_bus_send(bus, m, NULL);
}
static int send_changed_signal(sd_bus *bus, void *userdata) {
_cleanup_free_ char *p = NULL;
Job *j = userdata;
assert(bus);
assert(j);
p = job_dbus_path(j);
if (!p)
return -ENOMEM;
return sd_bus_emit_properties_changed(bus, p, "org.freedesktop.systemd1.Job", "State", NULL);
}
void bus_job_send_change_signal(Job *j) {
int r;
assert(j);
if (j->in_dbus_queue) {
LIST_REMOVE(dbus_queue, j->manager->dbus_job_queue, j);
j->in_dbus_queue = false;
}
r = bus_foreach_bus(j->manager, j->subscribed, j->sent_dbus_new_signal ? send_changed_signal : send_new_signal, j);
if (r < 0)
log_debug("Failed to send job change signal for %u: %s", j->id, strerror(-r));
j->sent_dbus_new_signal = true;
}
static int send_removed_signal(sd_bus *bus, void *userdata) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
_cleanup_free_ char *p = NULL;
Job *j = userdata;
int r;
assert(bus);
assert(j);
p = job_dbus_path(j);
if (!p)
return -ENOMEM;
r = sd_bus_message_new_signal(
bus,
&m,
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"JobRemoved");
if (r < 0)
return r;
r = sd_bus_message_append(m, "uoss", j->id, p, j->unit->id, job_result_to_string(j->result));
if (r < 0)
return r;
return sd_bus_send(bus, m, NULL);
}
void bus_job_send_removed_signal(Job *j) {
int r;
assert(j);
if (!j->sent_dbus_new_signal)
bus_job_send_change_signal(j);
r = bus_foreach_bus(j->manager, j->subscribed, send_removed_signal, j);
if (r < 0)
log_debug("Failed to send job remove signal for %u: %s", j->id, strerror(-r));
}