Systemd/src/core/dbus-scope.c
Lennart Poettering 4afd3348c7 tree-wide: expose "p"-suffix unref calls in public APIs to make gcc cleanup easy
GLIB has recently started to officially support the gcc cleanup
attribute in its public API, hence let's do the same for our APIs.

With this patch we'll define an xyz_unrefp() call for each public
xyz_unref() call, to make it easy to use inside a
__attribute__((cleanup())) expression. Then, all code is ported over to
make use of this.

The new calls are also documented in the man pages, with examples how to
use them (well, I only added docs where the _unref() call itself already
had docs, and the examples, only cover sd_bus_unrefp() and
sd_event_unrefp()).

This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we
tend to call our destructors these days.

Note that this defines no public macro that wraps gcc's attribute and
makes it easier to use. While I think it's our duty in the library to
make our stuff easy to use, I figure it's not our duty to make gcc's own
features easy to use on its own. Most likely, client code which wants to
make use of this should define its own:

       #define _cleanup_(function) __attribute__((cleanup(function)))

Or similar, to make the gcc feature easier to use.

Making this logic public has the benefit that we can remove three header
files whose only purpose was to define these functions internally.

See #2008.
2015-11-27 19:19:36 +01:00

232 lines
7.1 KiB
C

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2013 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 "alloc-util.h"
#include "bus-common-errors.h"
#include "bus-internal.h"
#include "bus-util.h"
#include "dbus-cgroup.h"
#include "dbus-kill.h"
#include "dbus-scope.h"
#include "dbus-unit.h"
#include "dbus.h"
#include "scope.h"
#include "selinux-access.h"
#include "unit.h"
static int bus_scope_abandon(sd_bus_message *message, void *userdata, sd_bus_error *error) {
Scope *s = userdata;
int r;
assert(message);
assert(s);
r = mac_selinux_unit_access_check(UNIT(s), message, "stop", error);
if (r < 0)
return r;
r = bus_verify_manage_units_async(UNIT(s)->manager, message, error);
if (r < 0)
return r;
if (r == 0)
return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */
r = scope_abandon(s);
if (r == -ESTALE)
return sd_bus_error_setf(error, BUS_ERROR_SCOPE_NOT_RUNNING, "Scope %s is not running, cannot abandon.", UNIT(s)->id);
if (r < 0)
return r;
return sd_bus_reply_method_return(message, NULL);
}
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_result, scope_result, ScopeResult);
const sd_bus_vtable bus_scope_vtable[] = {
SD_BUS_VTABLE_START(0),
SD_BUS_PROPERTY("Controller", "s", NULL, offsetof(Scope, controller), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("TimeoutStopUSec", "t", bus_property_get_usec, offsetof(Scope, timeout_stop_usec), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("Result", "s", property_get_result, offsetof(Scope, result), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
SD_BUS_SIGNAL("RequestStop", NULL, 0),
SD_BUS_METHOD("Abandon", NULL, NULL, bus_scope_abandon, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_VTABLE_END
};
static int bus_scope_set_transient_property(
Scope *s,
const char *name,
sd_bus_message *message,
UnitSetPropertiesMode mode,
sd_bus_error *error) {
int r;
assert(s);
assert(name);
assert(message);
if (streq(name, "PIDs")) {
unsigned n = 0;
uint32_t pid;
r = sd_bus_message_enter_container(message, 'a', "u");
if (r < 0)
return r;
while ((r = sd_bus_message_read(message, "u", &pid)) > 0) {
if (pid <= 1)
return -EINVAL;
if (mode != UNIT_CHECK) {
r = unit_watch_pid(UNIT(s), pid);
if (r < 0 && r != -EEXIST)
return r;
}
n++;
}
if (r < 0)
return r;
r = sd_bus_message_exit_container(message);
if (r < 0)
return r;
if (n <= 0)
return -EINVAL;
return 1;
} else if (streq(name, "Controller")) {
const char *controller;
char *c;
r = sd_bus_message_read(message, "s", &controller);
if (r < 0)
return r;
if (!isempty(controller) && !service_name_is_valid(controller))
return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Controller '%s' is not a valid bus name.", controller);
if (mode != UNIT_CHECK) {
if (isempty(controller))
c = NULL;
else {
c = strdup(controller);
if (!c)
return -ENOMEM;
}
free(s->controller);
s->controller = c;
}
return 1;
} else if (streq(name, "TimeoutStopUSec")) {
if (mode != UNIT_CHECK) {
r = sd_bus_message_read(message, "t", &s->timeout_stop_usec);
if (r < 0)
return r;
unit_write_drop_in_format(UNIT(s), mode, name, "[Scope]\nTimeoutStopSec="USEC_FMT"us\n", s->timeout_stop_usec);
} else {
r = sd_bus_message_skip(message, "t");
if (r < 0)
return r;
}
return 1;
}
return 0;
}
int bus_scope_set_property(
Unit *u,
const char *name,
sd_bus_message *message,
UnitSetPropertiesMode mode,
sd_bus_error *error) {
Scope *s = SCOPE(u);
int r;
assert(s);
assert(name);
assert(message);
r = bus_cgroup_set_property(u, &s->cgroup_context, name, message, mode, error);
if (r != 0)
return r;
if (u->load_state == UNIT_STUB) {
/* While we are created we still accept PIDs */
r = bus_scope_set_transient_property(s, name, message, mode, error);
if (r != 0)
return r;
r = bus_kill_context_set_transient_property(u, &s->kill_context, name, message, mode, error);
if (r != 0)
return r;
}
return 0;
}
int bus_scope_commit_properties(Unit *u) {
assert(u);
unit_update_cgroup_members_masks(u);
unit_realize_cgroup(u);
return 0;
}
int bus_scope_send_request_stop(Scope *s) {
_cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
_cleanup_free_ char *p = NULL;
int r;
assert(s);
if (!s->controller)
return 0;
p = unit_dbus_path(UNIT(s));
if (!p)
return -ENOMEM;
r = sd_bus_message_new_signal(
UNIT(s)->manager->api_bus,
&m,
p,
"org.freedesktop.systemd1.Scope",
"RequestStop");
if (r < 0)
return r;
return sd_bus_send_to(UNIT(s)->manager->api_bus, m, /* s->controller */ NULL, NULL);
}