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, 6 insertions, 4 deletions

diff --git a/src/login/logind-user-dbus.c b/src/login/logind-user-dbus.c
index 3ec3ff8e6..2a2825308 100644
--- a/src/login/logind-user-dbus.c
+++ b/src/login/logind-user-dbus.c
@@ -40,13 +40,14 @@
         "  <property name=\"RuntimePath\" type=\"s\" access=\"read\"/>\n" \
         "  <property name=\"DefaultControlGroup\" type=\"s\" access=\"read\"/>\n" \
         "  <property name=\"Service\" type=\"s\" access=\"read\"/>\n"   \
+        "  <property name=\"Slice\" type=\"s\" access=\"read\"/>\n"     \
         "  <property name=\"Display\" type=\"(so)\" access=\"read\"/>\n" \
         "  <property name=\"State\" type=\"s\" access=\"read\"/>\n"     \
         "  <property name=\"Sessions\" type=\"a(so)\" access=\"read\"/>\n" \
         "  <property name=\"IdleHint\" type=\"b\" access=\"read\"/>\n"  \
         "  <property name=\"IdleSinceHint\" type=\"t\" access=\"read\"/>\n" \
         "  <property name=\"IdleSinceHintMonotonic\" type=\"t\" access=\"read\"/>\n" \
-        " </interface>\n"                                               \
+        " </interface>\n"
 
 #define INTROSPECTION                                                   \
         DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE                       \
@@ -212,10 +213,10 @@ static int get_user_for_path(Manager *m, const char *path, User **_u) {
         assert(path);
         assert(_u);
 
-        if (!startswith(path, "/org/freedesktop/login1/user/"))
+        if (!startswith(path, "/org/freedesktop/login1/user/_"))
                 return -EINVAL;
 
-        r = safe_atolu(path + 29, &lu);
+        r = safe_atolu(path + 30, &lu);
         if (r < 0)
                 return r;
 
@@ -236,6 +237,7 @@ static const BusProperty bus_login_user_properties[] = {
         { "RuntimePath",            bus_property_append_string,      "s", offsetof(User, runtime_path),       true },
         { "DefaultControlGroup",    bus_user_append_default_cgroup,  "s", 0 },
         { "Service",                bus_property_append_string,      "s", offsetof(User, service),            true },
+        { "Slice",                  bus_property_append_string,      "s", offsetof(User, slice),              true },
         { "Display",                bus_user_append_display,      "(so)", 0 },
         { "State",                  bus_user_append_state,           "s", 0 },
         { "Sessions",               bus_user_append_sessions,    "a(so)", 0 },
@@ -348,7 +350,7 @@ char *user_bus_path(User *u) {
 
         assert(u);
 
-        if (asprintf(&s, "/org/freedesktop/login1/user/%llu", (unsigned long long) u->uid) < 0)
+        if (asprintf(&s, "/org/freedesktop/login1/user/_%llu", (unsigned long long) u->uid) < 0)
                 return NULL;
 
         return s;