logind: add infrastructure to keep track of machines, and move to slices

- This changes all logind cgroup objects to use slice objects rather
  than fixed croup locations.

- logind can now collect minimal information about running
  VMs/containers. As fixed cgroup locations can no longer be used we
  need an entity that keeps track of machine cgroups in whatever slice
  they might be located. Since logind already keeps track of users,
  sessions and seats this is a trivial addition.

- nspawn will now register with logind and pass various bits of metadata
  along. A new option "--slice=" has been added to place the container
  in a specific slice.

- loginctl gained commands to list, introspect and terminate machines.

- user.slice and machine.slice will now be pulled in by logind.service,
  since only logind.service requires this slice.

1 files changed, 64 insertions, 25 deletions

diff --git a/src/test/test-cgroup-util.c b/src/test/test-cgroup-util.c
index d4d58b320..aea8a7a1c 100644
--- a/src/test/test-cgroup-util.c
+++ b/src/test/test-cgroup-util.c
@@ -47,6 +47,17 @@ static void check_p_g_u(const char *path, int code, const char *result) {
         assert_se(streq_ptr(unit, result));
 }
 
+static void test_path_get_unit(void) {
+        check_p_g_u("/system.slice/foobar.service/sdfdsaf", 0, "foobar.service");
+        check_p_g_u("/system.slice/getty@.service/getty@tty5.service", 0, "getty@tty5.service");
+        check_p_g_u("/system.slice/getty@.service/getty@tty5.service/aaa/bbb", 0, "getty@tty5.service");
+        check_p_g_u("/system.slice/getty@.service/getty@tty5.service/", 0, "getty@tty5.service");
+        check_p_g_u("/system.slice/getty@tty6.service/tty5", 0, "getty@tty6.service");
+        check_p_g_u("sadfdsafsda", -EINVAL, NULL);
+        check_p_g_u("/system.slice/getty####@tty6.service/tty5", -EINVAL, NULL);
+        check_p_g_u("/system.slice/system-waldo.slice/foobar.service/sdfdsaf", 0, "foobar.service");
+}
+
 static void check_p_g_u_u(const char *path, int code, const char *result) {
         _cleanup_free_ char *unit = NULL;
 
@@ -54,39 +65,64 @@ static void check_p_g_u_u(const char *path, int code, const char *result) {
         assert_se(streq_ptr(unit, result));
 }
 
-static void test_path_get_unit(void) {
-        check_p_g_u("/system/foobar.service/sdfdsaf", 0, "foobar.service");
-        check_p_g_u("/system/getty@.service/getty@tty5.service", 0, "getty@tty5.service");
-        check_p_g_u("/system/getty@.service/getty@tty5.service/aaa/bbb", 0, "getty@tty5.service");
-        check_p_g_u("/system/getty@.service/getty@tty5.service/", 0, "getty@tty5.service");
-        check_p_g_u("/system/getty@tty6.service/tty5", 0, "getty@tty6.service");
-        check_p_g_u("sadfdsafsda", -ENOENT, NULL);
-        check_p_g_u("/system/getty####@tty6.service/tty5", -EINVAL, NULL);
+static void test_path_get_user_unit(void) {
+        check_p_g_u_u("/user.slice/1000.user/2.session/systemd-21548/foobar.service", 0, "foobar.service");
+        check_p_g_u_u("/user.slice/1002.user/2.session/systemd-21548/foobar.service/waldo", 0, "foobar.service");
+        check_p_g_u_u("/user.slice/1000.user/2.session/systemd-21548/foobar.service/waldo/uuuux", 0, "foobar.service");
+        check_p_g_u_u("/user.slice/1000.user/2.session/systemd-21548/waldo/waldo/uuuux", -EINVAL, NULL);
+        check_p_g_u_u("/user.slice/1000.user/2.session/foobar.service", 0, "foobar.service");
+        check_p_g_u_u("/user.slice/1000.user/2.session/systemd-21548/foobar@.service/foobar@pie.service/pa/po", 0, "foobar@pie.service");
+        check_p_g_u_u("/2.session/systemd-21548/foobar@.service/foobar@pie.service/pa/po", 0, "foobar@pie.service");
+        check_p_g_u_u("/xyz.slice/xyz-waldo.slice/77.session/systemd-21548/foobar@.service/foobar@pie.service/pa/po", 0, "foobar@pie.service");
+        check_p_g_u_u("/meh.service", -ENOENT, NULL);
 }
 
-static void test_path_get_user_unit(void) {
-        check_p_g_u_u("/user/lennart/2/systemd-21548/foobar.service", 0, "foobar.service");
-        check_p_g_u_u("/user/lennart/2/systemd-21548/foobar.service/waldo", 0, "foobar.service");
-        check_p_g_u_u("/user/lennart/2/systemd-21548/foobar.service/waldo/uuuux", 0, "foobar.service");
-        check_p_g_u_u("/user/lennart/2/systemd-21548/waldo/waldo/uuuux", -EINVAL, NULL);
-        check_p_g_u_u("/user/lennart/2/foobar.service", -ENOENT, NULL);
-        check_p_g_u_u("/user/lennart/2/systemd-21548/foobar@.service/foobar@pie.service/pa/po", 0, "foobar@pie.service");
+static void check_p_g_s(const char *path, int code, const char *result) {
+        _cleanup_free_ char *s = NULL;
+
+        assert_se(cg_path_get_session(path, &s) == code);
+        assert_se(streq_ptr(s, result));
 }
 
-static void test_get_paths(void) {
-        _cleanup_free_ char *a = NULL, *b = NULL, *c = NULL, *d = NULL;
+static void test_path_get_session(void) {
+        check_p_g_s("/user.slice/1000.user/2.session/systemd-21548/foobar.service", 0, "2");
+        check_p_g_s("/3.session", 0, "3");
+        check_p_g_s("", -ENOENT, 0);
+}
 
-        assert_se(cg_get_root_path(&a) >= 0);
-        log_info("Root = %s", a);
+static void check_p_g_o_u(const char *path, int code, uid_t result) {
+        uid_t uid = 0;
 
-        assert_se(cg_get_system_path(&b) >= 0);
-        log_info("System = %s", b);
+        assert_se(cg_path_get_owner_uid(path, &uid) == code);
+        assert_se(uid == result);
+}
+
+static void test_path_get_owner_uid(void) {
+        check_p_g_o_u("/user.slice/1000.user/2.session/systemd-21548/foobar.service", 0, 1000);
+        check_p_g_o_u("/1006.user", 0, 1006);
+        check_p_g_o_u("", -ENOENT, 0);
+}
 
-        assert_se(cg_get_user_path(&c) >= 0);
-        log_info("User = %s", c);
+static void check_p_g_m_n(const char *path, int code, const char *result) {
+        _cleanup_free_ char *m = NULL;
 
-        assert_se(cg_get_machine_path("harley", &d) >= 0);
-        log_info("Machine = %s", d);
+        assert_se(cg_path_get_machine_name(path, &m) == code);
+        assert_se(streq_ptr(m, result));
+}
+
+static void test_path_get_machine_name(void) {
+        check_p_g_m_n("/user.slice/foobar.machine", 0, "foobar");
+        check_p_g_m_n("/foobar.machine", 0, "foobar");
+        check_p_g_m_n("/user.slice/user-kuux.slice/foobar.machine", 0, "foobar");
+        check_p_g_m_n("/user.slice/user-kuux.slice/foobar.machine/asjhdkj", 0, "foobar");
+        check_p_g_m_n("", -ENOENT, NULL);
+}
+
+static void test_get_paths(void) {
+        _cleanup_free_ char *a = NULL;
+
+        assert_se(cg_get_root_path(&a) >= 0);
+        log_info("Root = %s", a);
 }
 
 static void test_proc(void) {
@@ -193,6 +229,9 @@ int main(void) {
         test_path_decode_unit();
         test_path_get_unit();
         test_path_get_user_unit();
+        test_path_get_session();
+        test_path_get_owner_uid();
+        test_path_get_machine_name();
         test_get_paths();
         test_proc();
         test_escape();