machined: split out machine registration stuff from logind

Embedded folks don't need the machine registration stuff, hence it's
nice to make this optional. Also, I'd expect that machinectl will grow
additional commands quickly, for example to join existing containers and
suchlike, hence it's better keeping that separate from loginctl.

1 files changed, 408 insertions, 0 deletions

diff --git a/src/machine/machined.c b/src/machine/machined.c
new file mode 100644
index 0000000000..3cf7f92f96
--- /dev/null
+++ b/src/machine/machined.c
@@ -0,0 +1,408 @@
+/*-*- 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 <pwd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/epoll.h>
+
+#include <systemd/sd-daemon.h>
+
+#include "machined.h"
+#include "dbus-common.h"
+#include "dbus-loop.h"
+#include "strv.h"
+#include "conf-parser.h"
+#include "mkdir.h"
+#include "cgroup-util.h"
+
+Manager *manager_new(void) {
+        Manager *m;
+
+        m = new0(Manager, 1);
+        if (!m)
+                return NULL;
+
+        m->bus_fd = -1;
+        m->epoll_fd = -1;
+
+        m->machines = hashmap_new(string_hash_func, string_compare_func);
+        m->machine_units = hashmap_new(string_hash_func, string_compare_func);
+
+        if (!m->machines || !m->machine_units) {
+                manager_free(m);
+                return NULL;
+        }
+
+        return m;
+}
+
+void manager_free(Manager *m) {
+        Machine *machine;
+
+        assert(m);
+
+        while ((machine = hashmap_first(m->machines)))
+                machine_free(machine);
+
+        hashmap_free(m->machines);
+        hashmap_free(m->machine_units);
+
+        if (m->bus) {
+                dbus_connection_flush(m->bus);
+                dbus_connection_close(m->bus);
+                dbus_connection_unref(m->bus);
+        }
+
+        if (m->bus_fd >= 0)
+                close_nointr_nofail(m->bus_fd);
+
+        if (m->epoll_fd >= 0)
+                close_nointr_nofail(m->epoll_fd);
+
+        free(m);
+}
+
+int manager_add_machine(Manager *m, const char *name, Machine **_machine) {
+        Machine *machine;
+
+        assert(m);
+        assert(name);
+
+        machine = hashmap_get(m->machines, name);
+        if (machine) {
+                if (_machine)
+                        *_machine = machine;
+
+                return 0;
+        }
+
+        machine = machine_new(m, name);
+        if (!m)
+                return -ENOMEM;
+
+        if (_machine)
+                *_machine = machine;
+
+        return 0;
+}
+
+int manager_enumerate_machines(Manager *m) {
+        _cleanup_closedir_ DIR *d = NULL;
+        struct dirent *de;
+        int r = 0;
+
+        assert(m);
+
+        /* Read in machine data stored on disk */
+        d = opendir("/run/systemd/machines");
+        if (!d) {
+                if (errno == ENOENT)
+                        return 0;
+
+                log_error("Failed to open /run/systemd/machines: %m");
+                return -errno;
+        }
+
+        FOREACH_DIRENT(de, d, return -errno) {
+                struct Machine *machine;
+                int k;
+
+                if (!dirent_is_file(de))
+                        continue;
+
+                k = manager_add_machine(m, de->d_name, &machine);
+                if (k < 0) {
+                        log_error("Failed to add machine by file name %s: %s", de->d_name, strerror(-k));
+
+                        r = k;
+                        continue;
+                }
+
+                machine_add_to_gc_queue(machine);
+
+                k = machine_load(machine);
+                if (k < 0)
+                        r = k;
+        }
+
+        return r;
+}
+
+int manager_get_machine_by_pid(Manager *m, pid_t pid, Machine **machine) {
+        _cleanup_free_ char *unit = NULL;
+        Machine *mm;
+        int r;
+
+        assert(m);
+        assert(pid >= 1);
+        assert(machine);
+
+        r = cg_pid_get_unit(pid, &unit);
+        if (r < 0)
+                return r;
+
+        mm = hashmap_get(m->machine_units, unit);
+        if (!mm)
+                return 0;
+
+        *machine = mm;
+        return 1;
+}
+
+static int manager_connect_bus(Manager *m) {
+        DBusError error;
+        int r;
+        struct epoll_event ev = {
+                .events = EPOLLIN,
+                .data.u32 = FD_BUS,
+        };
+
+        assert(m);
+        assert(!m->bus);
+        assert(m->bus_fd < 0);
+
+        dbus_error_init(&error);
+
+        m->bus = dbus_bus_get_private(DBUS_BUS_SYSTEM, &error);
+        if (!m->bus) {
+                log_error("Failed to get system D-Bus connection: %s", bus_error_message(&error));
+                r = -ECONNREFUSED;
+                goto fail;
+        }
+
+        if (!dbus_connection_register_object_path(m->bus, "/org/freedesktop/machine1", &bus_manager_vtable, m) ||
+            !dbus_connection_register_fallback(m->bus, "/org/freedesktop/machine1/machine", &bus_machine_vtable, m) ||
+            !dbus_connection_add_filter(m->bus, bus_message_filter, m, NULL)) {
+                r = log_oom();
+                goto fail;
+        }
+
+        dbus_bus_add_match(m->bus,
+                           "type='signal',"
+                           "sender='org.freedesktop.systemd1',"
+                           "interface='org.freedesktop.systemd1.Manager',"
+                           "member='JobRemoved',"
+                           "path='/org/freedesktop/systemd1'",
+                           &error);
+        if (dbus_error_is_set(&error)) {
+                log_error("Failed to add match for JobRemoved: %s", bus_error_message(&error));
+                dbus_error_free(&error);
+        }
+
+        dbus_bus_add_match(m->bus,
+                           "type='signal',"
+                           "sender='org.freedesktop.systemd1',"
+                           "interface='org.freedesktop.DBus.Properties',"
+                           "member='PropertiesChanged'",
+                           &error);
+        if (dbus_error_is_set(&error)) {
+                log_error("Failed to add match for PropertiesChanged: %s", bus_error_message(&error));
+                dbus_error_free(&error);
+        }
+
+        r = bus_method_call_with_reply(
+                        m->bus,
+                        "org.freedesktop.systemd1",
+                        "/org/freedesktop/systemd1",
+                        "org.freedesktop.systemd1.Manager",
+                        "Subscribe",
+                        NULL,
+                        &error,
+                        DBUS_TYPE_INVALID);
+        if (r < 0) {
+                log_error("Failed to enable subscription: %s", bus_error(&error, r));
+                dbus_error_free(&error);
+        }
+
+        r = dbus_bus_request_name(m->bus, "org.freedesktop.machine1", DBUS_NAME_FLAG_DO_NOT_QUEUE, &error);
+        if (dbus_error_is_set(&error)) {
+                log_error("Failed to register name on bus: %s", bus_error_message(&error));
+                r = -EIO;
+                goto fail;
+        }
+
+        if (r != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER)  {
+                log_error("Failed to acquire name.");
+                r = -EEXIST;
+                goto fail;
+        }
+
+        m->bus_fd = bus_loop_open(m->bus);
+        if (m->bus_fd < 0) {
+                r = m->bus_fd;
+                goto fail;
+        }
+
+        if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->bus_fd, &ev) < 0)
+                goto fail;
+
+        return 0;
+
+fail:
+        dbus_error_free(&error);
+
+        return r;
+}
+
+void manager_gc(Manager *m, bool drop_not_started) {
+        Machine *machine;
+
+        assert(m);
+
+        while ((machine = m->machine_gc_queue)) {
+                LIST_REMOVE(Machine, gc_queue, m->machine_gc_queue, machine);
+                machine->in_gc_queue = false;
+
+                if (machine_check_gc(machine, drop_not_started) == 0) {
+                        machine_stop(machine);
+                        machine_free(machine);
+                }
+        }
+}
+
+int manager_startup(Manager *m) {
+        int r;
+        Machine *machine;
+        Iterator i;
+
+        assert(m);
+        assert(m->epoll_fd <= 0);
+
+        m->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
+        if (m->epoll_fd < 0)
+                return -errno;
+
+        /* 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);
+
+        return 0;
+}
+
+int manager_run(Manager *m) {
+        assert(m);
+
+        for (;;) {
+                struct epoll_event event;
+                int n;
+
+                manager_gc(m, true);
+
+                if (dbus_connection_dispatch(m->bus) != DBUS_DISPATCH_COMPLETE)
+                        continue;
+
+                manager_gc(m, true);
+
+                n = epoll_wait(m->epoll_fd, &event, 1, -1);
+                if (n < 0) {
+                        if (errno == EINTR || errno == EAGAIN)
+                                continue;
+
+                        log_error("epoll() failed: %m");
+                        return -errno;
+                }
+
+                if (n == 0)
+                        continue;
+
+                switch (event.data.u32) {
+
+                case FD_BUS:
+                        bus_loop_dispatch(m->bus_fd);
+                        break;
+
+                default:
+                        assert_not_reached("Unknown fd");
+                }
+        }
+
+        return 0;
+}
+
+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/seats/ to determine whether
+         * machined is available, so please always make sure this check
+         * stays in. */
+        mkdir_label("/run/systemd/machines", 0755);
+
+        m = manager_new();
+        if (!m) {
+                r = log_oom();
+                goto finish;
+        }
+
+        r = manager_startup(m);
+        if (r < 0) {
+                log_error("Failed to fully start up daemon: %s", strerror(-r));
+                goto finish;
+        }
+
+        log_debug("systemd-machined running as pid %lu", (unsigned long) getpid());
+
+        sd_notify(false,
+                  "READY=1\n"
+                  "STATUS=Processing requests...");
+
+        r = manager_run(m);
+
+        log_debug("systemd-machined stopped as pid %lu", (unsigned long) getpid());
+
+finish:
+        sd_notify(false,
+                  "STATUS=Shutting down...");
+
+        if (m)
+                manager_free(m);
+
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}