Systemd/src/machine/machined.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

410 lines
12 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 <errno.h>
#include <string.h>
#include <unistd.h>
#include "sd-daemon.h"
#include "alloc-util.h"
#include "bus-error.h"
#include "bus-util.h"
#include "cgroup-util.h"
#include "dirent-util.h"
#include "fd-util.h"
#include "formats-util.h"
#include "hostname-util.h"
#include "label.h"
#include "machine-image.h"
#include "machined.h"
#include "signal-util.h"
Manager *manager_new(void) {
Manager *m;
int r;
m = new0(Manager, 1);
if (!m)
return NULL;
m->machines = hashmap_new(&string_hash_ops);
m->machine_units = hashmap_new(&string_hash_ops);
m->machine_leaders = hashmap_new(NULL);
if (!m->machines || !m->machine_units || !m->machine_leaders) {
manager_free(m);
return NULL;
}
r = sd_event_default(&m->event);
if (r < 0) {
manager_free(m);
return NULL;
}
sd_event_set_watchdog(m->event, true);
return m;
}
void manager_free(Manager *m) {
Machine *machine;
Image *i;
assert(m);
while ((machine = hashmap_first(m->machines)))
machine_free(machine);
hashmap_free(m->machines);
hashmap_free(m->machine_units);
hashmap_free(m->machine_leaders);
while ((i = hashmap_steal_first(m->image_cache)))
image_unref(i);
hashmap_free(m->image_cache);
sd_event_source_unref(m->image_cache_defer_event);
bus_verify_polkit_async_registry_free(m->polkit_registry);
sd_bus_unref(m->bus);
sd_event_unref(m->event);
free(m);
}
static int manager_add_host_machine(Manager *m) {
_cleanup_free_ char *rd = NULL, *unit = NULL;
sd_id128_t mid;
Machine *t;
int r;
if (m->host_machine)
return 0;
r = sd_id128_get_machine(&mid);
if (r < 0)
return log_error_errno(r, "Failed to get machine ID: %m");
rd = strdup("/");
if (!rd)
return log_oom();
unit = strdup("-.slice");
if (!unit)
return log_oom();
t = machine_new(m, MACHINE_HOST, ".host");
if (!t)
return log_oom();
t->leader = 1;
t->id = mid;
t->root_directory = rd;
t->unit = unit;
rd = unit = NULL;
dual_timestamp_from_boottime_or_monotonic(&t->timestamp, 0);
m->host_machine = t;
return 0;
}
int manager_enumerate_machines(Manager *m) {
_cleanup_closedir_ DIR *d = NULL;
struct dirent *de;
int r = 0;
assert(m);
r = manager_add_host_machine(m);
if (r < 0)
return r;
/* Read in machine data stored on disk */
d = opendir("/run/systemd/machines");
if (!d) {
if (errno == ENOENT)
return 0;
return log_error_errno(errno, "Failed to open /run/systemd/machines: %m");
}
FOREACH_DIRENT(de, d, return -errno) {
struct Machine *machine;
int k;
if (!dirent_is_file(de))
continue;
/* Ignore symlinks that map the unit name to the machine */
if (startswith(de->d_name, "unit:"))
continue;
if (!machine_name_is_valid(de->d_name))
continue;
k = manager_add_machine(m, de->d_name, &machine);
if (k < 0) {
r = log_error_errno(k, "Failed to add machine by file name %s: %m", de->d_name);
continue;
}
machine_add_to_gc_queue(machine);
k = machine_load(machine);
if (k < 0)
r = k;
}
return r;
}
static int manager_connect_bus(Manager *m) {
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
int r;
assert(m);
assert(!m->bus);
r = sd_bus_default_system(&m->bus);
if (r < 0)
return log_error_errno(r, "Failed to connect to system bus: %m");
r = sd_bus_add_object_vtable(m->bus, NULL, "/org/freedesktop/machine1", "org.freedesktop.machine1.Manager", manager_vtable, m);
if (r < 0)
return log_error_errno(r, "Failed to add manager object vtable: %m");
r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/machine1/machine", "org.freedesktop.machine1.Machine", machine_vtable, machine_object_find, m);
if (r < 0)
return log_error_errno(r, "Failed to add machine object vtable: %m");
r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/machine1/machine", machine_node_enumerator, m);
if (r < 0)
return log_error_errno(r, "Failed to add machine enumerator: %m");
r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/machine1/image", "org.freedesktop.machine1.Image", image_vtable, image_object_find, m);
if (r < 0)
return log_error_errno(r, "Failed to add image object vtable: %m");
r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/machine1/image", image_node_enumerator, m);
if (r < 0)
return log_error_errno(r, "Failed to add image enumerator: %m");
r = sd_bus_add_match(m->bus,
NULL,
"type='signal',"
"sender='org.freedesktop.systemd1',"
"interface='org.freedesktop.systemd1.Manager',"
"member='JobRemoved',"
"path='/org/freedesktop/systemd1'",
match_job_removed,
m);
if (r < 0)
return log_error_errno(r, "Failed to add match for JobRemoved: %m");
r = sd_bus_add_match(m->bus,
NULL,
"type='signal',"
"sender='org.freedesktop.systemd1',"
"interface='org.freedesktop.systemd1.Manager',"
"member='UnitRemoved',"
"path='/org/freedesktop/systemd1'",
match_unit_removed,
m);
if (r < 0)
return log_error_errno(r, "Failed to add match for UnitRemoved: %m");
r = sd_bus_add_match(m->bus,
NULL,
"type='signal',"
"sender='org.freedesktop.systemd1',"
"interface='org.freedesktop.DBus.Properties',"
"member='PropertiesChanged',"
"arg0='org.freedesktop.systemd1.Unit'",
match_properties_changed,
m);
if (r < 0)
return log_error_errno(r, "Failed to add match for PropertiesChanged: %m");
r = sd_bus_add_match(m->bus,
NULL,
"type='signal',"
"sender='org.freedesktop.systemd1',"
"interface='org.freedesktop.systemd1.Manager',"
"member='Reloading',"
"path='/org/freedesktop/systemd1'",
match_reloading,
m);
if (r < 0)
return log_error_errno(r, "Failed to add match for Reloading: %m");
r = sd_bus_call_method(
m->bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"Subscribe",
&error,
NULL, NULL);
if (r < 0) {
log_error("Failed to enable subscription: %s", bus_error_message(&error, r));
return r;
}
r = sd_bus_request_name(m->bus, "org.freedesktop.machine1", 0);
if (r < 0)
return log_error_errno(r, "Failed to register name: %m");
r = sd_bus_attach_event(m->bus, m->event, 0);
if (r < 0)
return log_error_errno(r, "Failed to attach bus to event loop: %m");
return 0;
}
void manager_gc(Manager *m, bool drop_not_started) {
Machine *machine;
assert(m);
while ((machine = m->machine_gc_queue)) {
LIST_REMOVE(gc_queue, m->machine_gc_queue, machine);
machine->in_gc_queue = false;
/* First, if we are not closing yet, initiate stopping */
if (!machine_check_gc(machine, drop_not_started) &&
machine_get_state(machine) != MACHINE_CLOSING)
machine_stop(machine);
/* Now, the stop stop probably made this referenced
* again, but if it didn't, then it's time to let it
* go entirely. */
if (!machine_check_gc(machine, drop_not_started)) {
machine_finalize(machine);
machine_free(machine);
}
}
}
int manager_startup(Manager *m) {
Machine *machine;
Iterator i;
int r;
assert(m);
/* Connect to the bus */
r = manager_connect_bus(m);
if (r < 0)
return r;
/* Deserialize state */
manager_enumerate_machines(m);
/* Remove stale objects before we start them */
manager_gc(m, false);
/* And start everything */
HASHMAP_FOREACH(machine, m->machines, i)
machine_start(machine, NULL, NULL);
return 0;
}
static bool check_idle(void *userdata) {
Manager *m = userdata;
manager_gc(m, true);
return hashmap_isempty(m->machines);
}
int manager_run(Manager *m) {
assert(m);
return bus_event_loop_with_idle(
m->event,
m->bus,
"org.freedesktop.machine1",
DEFAULT_EXIT_USEC,
check_idle, m);
}
int main(int argc, char *argv[]) {
Manager *m = NULL;
int r;
log_set_target(LOG_TARGET_AUTO);
log_set_facility(LOG_AUTH);
log_parse_environment();
log_open();
umask(0022);
if (argc != 1) {
log_error("This program takes no arguments.");
r = -EINVAL;
goto finish;
}
/* Always create the directories people can create inotify
* watches in. Note that some applications might check for the
* existence of /run/systemd/machines/ to determine whether
* machined is available, so please always make sure this
* check stays in. */
mkdir_label("/run/systemd/machines", 0755);
assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, -1) >= 0);
m = manager_new();
if (!m) {
r = log_oom();
goto finish;
}
r = manager_startup(m);
if (r < 0) {
log_error_errno(r, "Failed to fully start up daemon: %m");
goto finish;
}
log_debug("systemd-machined running as pid "PID_FMT, getpid());
sd_notify(false,
"READY=1\n"
"STATUS=Processing requests...");
r = manager_run(m);
log_debug("systemd-machined stopped as pid "PID_FMT, getpid());
finish:
manager_free(m);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}