wip: start adding systemd support

Only started, still more to do, just sketching at this point.

configure.ac

@@ -161,10 +161,22 @@ AC_PATH_PROG([XSLTPROC], [xsltproc])
 
 # systemd
 
+PKG_CHECK_MODULES(SYSTEMD, [libsystemd-login libsystemd-daemon],
+                  [have_systemd=yes], [have_systemd=no])
+AC_SUBST(SYSTEMD_CFLAGS)
+AC_SUBST(SYSTEMD_LIBS)
+
+LIBACCOUNTSSERVICE_LIBS="$LIBACCOUNTSSERVICE_LIBS $SYSTEMD_LIBS"
+LIBACCOUNTSSERVICE_CFLAGS="$LIBACCOUNTSSERVICE_CFLAGS $SYSTEMD_CFLAGS"
+
+if test "x$have_systemd" != "no" ; then
+        AC_DEFINE(WITH_SYSTEMD, 1, [Define to enable systemd support])
+fi
+
 AC_ARG_WITH([systemdsystemunitdir],
         AS_HELP_STRING([--with-systemdsystemunitdir=DIR], [Directory for systemd service files]),
         [],
-        [with_systemdsystemunitdir=yes])
+        [with_systemdsystemunitdir=$have_systemd])
 if test "x$with_systemdsystemunitdir" = "xyes"; then
     with_systemdsystemunitdir=$($PKG_CONFIG --variable=systemdsystemunitdir systemd)
 fi

src/libaccountsservice/act-user-manager.c

@@ -39,6 +39,12 @@
 #include <glib/gstdio.h>
 #include <glib-object.h>
 #include <gio/gio.h>
+#include <gio/gunixinputstream.h>
+
+#ifdef WITH_SYSTEMD
+#include <systemd/sd-daemon.h>
+#include <systemd/sd-login.h>
+#endif
 
 #include "act-user-manager.h"
 #include "act-user-private.h"
@@ -76,6 +82,10 @@ typedef struct
         char                        *session_id;
         ConsoleKitSeat              *seat_proxy;
         ConsoleKitSession           *session_proxy;
+#ifdef WITH_SYSTEMD
+        sd_login_monitor            *session_monitor;
+        GInputStream                *session_monitor_stream;
+#endif
 } ActUserManagerSeat;
 
 typedef enum {
@@ -195,33 +205,14 @@ act_user_manager_error_quark (void)
 }
 
 static gboolean
-start_new_login_session (ActUserManager *manager)
-{
-        GError  *error;
-        gboolean res;
-
-        res = g_spawn_command_line_async ("gdmflexiserver -s", &error);
-        if (! res) {
-                if (error != NULL) {
-                        g_warning ("Unable to start new login: %s", error->message);
-                        g_error_free (error);
-                } else {
-                        g_warning ("Unable to start new login");
-                }
-        }
-
-        return res;
-}
-
-static gboolean
-activate_session_id (ActUserManager *manager,
-                     const char     *seat_id,
-                     const char     *session_id)
+activate_console_kit_session_id (ActUserManager *manager,
+                                 const char     *seat_id,
+                                 const char     *session_id)
 {
         ConsoleKitSeat *proxy;
         GError         *error = NULL;
         gboolean        res = FALSE;
-  
+
         proxy = console_kit_seat_proxy_new_sync (manager->priv->connection,
                                                  G_DBUS_PROXY_FLAGS_NONE,
                                                  CK_NAME,
@@ -243,9 +234,57 @@ activate_session_id (ActUserManager *manager,
         return TRUE;
 }
 
+#ifdef WITH_SYSTEMD
 static gboolean
-session_is_login_window (ActUserManager *manager,
-                         const char     *session_id)
+activate_systemd_session_id (ActUserManager *manager,
+                             const char     *seat_id,
+                             const char     *session_id)
+{
+        GDBusConnection *connection;
+        GVariant *reply;
+        GError *error;
+
+        error = NULL;
+        connection = g_bus_get_sync (G_BUS_TYPE_SYSTEM, NULL, &error);
+
+
+        if (connection == NULL) {
+                goto failed;
+        }
+
+        reply = g_dbus_connection_call_sync (connection,
+                                             "org.freedesktop.login1",
+                                             "/org/freedesktop/login1",
+                                             "org.freedesktop.login1.Manager",
+                                             "ActivateSessionOnSeat",
+                                             g_variant_new ("(ss)",
+                                                            seat_id,
+                                                            session_id),
+                                             NULL,
+                                             G_DBUS_CALL_FLAGS_NONE,
+                                             -1,
+                                             NULL,
+                                             &error);
+        g_object_unref (connection);
+
+        if (reply == NULL) {
+                goto failed;
+        }
+
+        g_object_unref (reply);
+
+        return TRUE;
+
+failed:
+        g_warning ("Unable to activate session: %s", error->message);
+        g_error_free (error);
+        return FALSE;
+}
+#endif
+
+static gboolean
+_ck_session_is_login_window (ActUserManager *manager,
+                             const char     *session_id)
 {
         ConsoleKitSession *proxy;
         GError            *error = NULL;
@@ -280,99 +319,94 @@ session_is_login_window (ActUserManager *manager,
         return ret;
 }
 
-static char *
-_get_login_window_session_id (ActUserManager *manager)
+#ifdef WITH_SYSTEMD
+static gboolean
+_systemd_session_is_login_window (ActUserManager *manager,
+                                  const char     *session_id)
 {
-        gboolean    can_activate_sessions;
-        GError     *error = NULL;
-        gchar     **sessions, **i;
-        char       *primary_ssid;
-
-        if (manager->priv->seat.id == NULL || manager->priv->seat.id[0] == '\0') {
-                g_debug ("ActUserManager: display seat ID is not set; can't switch sessions");
-                return NULL;
-        }
+        int   res;
+        int   ret;
+        char *session_class;
 
-        can_activate_sessions = act_user_manager_can_switch (manager);
+        ret = FALSE;
+        res = sd_session_get_class (session_id, &session_class);
 
-        if (! can_activate_sessions) {
-                g_debug ("ActUserManager: seat is unable to activate sessions");
-                return NULL;
+        if (res < 0) {
+            g_debug ("failed to determine class of session %s: %s",
+                     session_id,
+                     strerror (-res));
+            goto out;
         }
 
-        if (!console_kit_seat_call_get_sessions_sync (manager->priv->seat.seat_proxy, &sessions, NULL, &error)) {
-                if (error != NULL) {
-                        g_warning ("unable to determine sessions for user: %s",
-                                   error->message);
-                        g_error_free (error);
-                } else {
-                        g_warning ("unable to determine sessions for user");
-                }
-                return NULL;
+        if (g_strcmp0 (session_class, "greeter") == 0) {
+            ret = TRUE;
         }
 
-        primary_ssid = NULL;
-        for (i = sessions; i; i++) {
-                if (session_is_login_window (manager, *i)) {
-                        primary_ssid = g_strdup (*i);
-                        break;
-                }
+        free (session_class);
+
+out:
+        return ret;
+}
+#endif
+
+static gboolean
+session_is_login_window (ActUserManager *manager,
+                         const char     *session_id)
+{
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                return _systemd_session_is_login_window (manager, session_id);
         }
-        g_strfreev (sessions);
+#endif
 
-        return primary_ssid;
+        return _ck_session_is_login_window (manager, session_id);
 }
 
 gboolean
 act_user_manager_goto_login_session (ActUserManager *manager)
 {
-        gboolean ret;
         gboolean res;
-        char    *ssid;
+        GError  *error;
 
         g_return_val_if_fail (ACT_IS_USER_MANAGER (manager), FALSE);
         g_return_val_if_fail (manager->priv->is_loaded, FALSE);
 
-        ret = FALSE;
-
-        /* First look for any existing LoginWindow sessions on the seat.
-           If none are found, create a new one. */
-
-        ssid = _get_login_window_session_id (manager);
-        if (ssid != NULL) {
-                res = activate_session_id (manager, manager->priv->seat.id, ssid);
-                if (res) {
-                        ret = TRUE;
+        res = g_spawn_command_line_async ("gdmflexiserver", &error);
+        if (! res) {
+                if (error != NULL) {
+                        g_warning ("Unable to start new login: %s", error->message);
+                        g_error_free (error);
+                } else {
+                        g_warning ("Unable to start new login");
                 }
         }
 
-        if (! ret) {
-                res = start_new_login_session (manager);
-                if (res) {
-                        ret = TRUE;
-                }
-        }
+        return res;
 
-        return ret;
 }
 
+#ifdef WITH_SYSTEMD
 gboolean
-act_user_manager_can_switch (ActUserManager *manager)
+_can_activate_systemd_sessions (ActUserManager *manager)
 {
-        gboolean  can_activate_sessions;
-        GError   *error = NULL;
+        int res;
 
-        if (!manager->priv->is_loaded) {
-                g_debug ("ActUserManager: Unable to switch sessions until fully loaded");
+        res = sd_seat_can_multi_session (manager->priv->seat.id);
+        if (res < 0) {
+                g_warning ("unable to determine if seat can activate sessions: %s",
+                           strerror (-res));
                 return FALSE;
         }
 
-        if (manager->priv->seat.id == NULL || manager->priv->seat.id[0] == '\0') {
-                g_debug ("ActUserManager: display seat ID is not set; can't switch sessions");
-                return FALSE;
-        }
+        return res > 0;
+}
+#endif
 
-        g_debug ("ActUserManager: checking if seat can activate sessions");
+gboolean
+_can_activate_console_kit_sessions (ActUserManager *manager)
+{
+        GError   *error = NULL;
+        gboolean  can_activate_sessions = FALSE;
 
         if (!console_kit_seat_call_can_activate_sessions_sync (manager->priv->seat.seat_proxy, &can_activate_sessions, NULL, &error)) {
                 if (error != NULL) {
@@ -388,6 +422,31 @@ act_user_manager_can_switch (ActUserManager *manager)
         return can_activate_sessions;
 }
 
+gboolean
+act_user_manager_can_switch (ActUserManager *manager)
+{
+        if (!manager->priv->is_loaded) {
+                g_debug ("ActUserManager: Unable to switch sessions until fully loaded");
+                return FALSE;
+        }
+
+        if (manager->priv->seat.id == NULL || manager->priv->seat.id[0] == '\0') {
+                g_debug ("ActUserManager: display seat ID is not set; can't switch sessions");
+                return FALSE;
+        }
+
+        g_debug ("ActUserManager: checking if seat can activate sessions");
+
+
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                return _can_activate_systemd_sessions (manager);
+        }
+#endif
+
+        return _can_activate_console_kit_sessions (manager);
+}
+
 gboolean
 act_user_manager_activate_user_session (ActUserManager *manager,
                                         ActUser        *user)
@@ -415,7 +474,13 @@ act_user_manager_activate_user_session (ActUserManager *manager,
                 goto out;
         }
 
-        res = activate_session_id (manager, manager->priv->seat.id, ssid);
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                return activate_systemd_session_id (manager, manager->priv->seat.id, ssid);
+        }
+#endif
+
+        res = activate_console_kit_session_id (manager, manager->priv->seat.id, ssid);
         if (! res) {
                 g_debug ("ActUserManager: unable to activate session: %s", ssid);
                 goto out;
@@ -499,9 +564,42 @@ on_get_seat_id_finished (GObject        *object,
         g_object_unref (manager);
 }
 
+#ifdef WITH_SYSTEMD
+static void
+_get_systemd_seat_id (ActUserManager *manager)
+{
+        int   res;
+        char *seat_id;
+
+        res = sd_session_get_seat (manager->priv->seat.session_id,
+                                   &seat_id);
+
+        if (res < 0) {
+                g_warning ("Could not get seat of session '%s': %s",
+                           manager->priv->seat.session_id,
+                           strerror (-res));
+                unload_seat (manager);
+                return;
+        }
+
+        manager->priv->seat.id = g_strdup (seat_id);
+        free (seat_id);
+
+        manager->priv->seat.state++;
+
+        load_seat_incrementally (manager);
+}
+#endif
+
 static void
 get_seat_id_for_current_session (ActUserManager *manager)
 {
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                _get_systemd_seat_id (manager);
+                return;
+        }
+#endif
         console_kit_session_call_get_seat_id (manager->priv->seat.session_proxy,
                                               NULL,
                                               on_get_seat_id_finished,
@@ -808,9 +906,41 @@ on_get_current_session_finished (GObject        *object,
         g_object_unref (manager);
 }
 
+#ifdef WITH_SYSTEMD
+static void
+_get_current_systemd_session_id (ActUserManager *manager)
+{
+        char *session_id;
+        int   res;
+
+        res = sd_seat_get_active ("seat0", &session_id, NULL);
+
+        if (res < 0) {
+                g_debug ("Failed to identify the current session: %s",
+                         strerror (-res));
+                unload_seat (manager);
+                return;
+        }
+
+        manager->priv->seat.session_id = g_strdup (session_id);
+        free (session_id);
+
+        manager->priv->seat.state++;
+
+        load_seat_incrementally (manager);
+
+}
+#endif
+
 static void
 get_current_session_id (ActUserManager *manager)
 {
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                _get_current_systemd_session_id (manager);
+                return;
+        }
+#endif
         console_kit_manager_call_get_current_session (manager->priv->ck_manager_proxy, NULL,
                                                       on_get_current_session_finished,
                                                       g_object_ref (manager));
@@ -841,6 +971,13 @@ static void
 get_proxy_for_new_session (ActUserManagerNewSession *new_session)
 {
         GError            *error = NULL;
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                new_session->state++;
+                load_new_session_incrementally (new_session);
+                return;
+        }
+#endif
 
         new_session->proxy = console_kit_session_proxy_new_sync (new_session->manager->priv->connection,
                                                                  G_DBUS_PROXY_FLAGS_NONE,
@@ -893,9 +1030,40 @@ on_get_unix_user_finished (GObject      *object,
         load_new_session_incrementally (new_session);
 }
 
+#ifdef WITH_SYSTEMD
+static void
+_get_uid_for_new_systemd_session (ActUserManagerNewSession *new_session)
+{
+        uid_t uid;
+        int   res;
+
+        res = sd_session_get_uid (new_session->id, &uid);
+
+        if (res < 0) {
+                g_debug ("Failed to get uid of session '%s': %s",
+                         new_session->id,
+                         strerror (-res));
+                unload_new_session (new_session);
+                return;
+        }
+
+        new_session->uid = uid;
+        new_session->state++;
+
+        load_new_session_incrementally (new_session);
+}
+#endif
+
 static void
 get_uid_for_new_session (ActUserManagerNewSession *new_session)
 {
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                _get_uid_for_new_systemd_session (new_session);
+                return;
+        }
+#endif
+
         g_assert (new_session->proxy != NULL);
 
         console_kit_session_call_get_unix_user (new_session->proxy,
@@ -1061,9 +1229,45 @@ on_get_x11_display_finished (GObject      *object,
         load_new_session_incrementally (new_session);
 }
 
+#ifdef WITH_SYSTEMD
+static void
+_get_x11_display_for_new_systemd_session (ActUserManagerNewSession *new_session)
+{
+        char *x11_display;
+        int   res;
+
+        res = sd_session_get_display (new_session->id,
+                                      &x11_display);
+
+        if (res < 0) {
+                g_debug ("ActUserManager: Failed to get the x11 display of session '%s': %s",
+                         new_session->id,
+                         strerror (-res));
+                unload_new_session (new_session);
+                return;
+        }
+
+        g_debug ("ActUserManager: Found x11 display of session '%s': %s",
+                 new_session->id, x11_display);
+
+        new_session->x11_display = g_strdup (x11_display);
+        free (x11_display);
+        new_session->state++;
+
+        load_new_session_incrementally (new_session);
+}
+#endif
+
 static void
 get_x11_display_for_new_session (ActUserManagerNewSession *new_session)
 {
+#ifdef WITH_SYSTEMD
+        if (sd_booted () > 0) {
+                _get_x11_display_for_new_systemd_session (new_session);
+                return;
+        }
+#endif
+
         g_assert (new_session->proxy != NULL);
 
         console_kit_session_call_get_x11_display (new_session->proxy,
@@ -1186,9 +1390,8 @@ match_new_session_cmpfunc (gconstpointer a,
 }
 
 static void
-seat_session_removed (GDBusProxy     *seat_proxy,
-                      const char     *session_id,
-                      ActUserManager *manager)
+_remove_session (ActUserManager *manager,
+                 const char     *session_id)
 {
         ActUser       *user;
         GSList        *found;
@@ -1239,11 +1442,209 @@ seat_session_removed (GDBusProxy     *seat_proxy,
         _act_user_remove_session (user, session_id);
 }
 
+static void
+seat_session_removed (GDBusProxy     *seat_proxy,
+                      const char     *session_id,
+                      ActUserManager *manager)
+{
+        _remove_session (manager, session_id);
+}
+
+#ifdef WITH_SYSTEMD
+
+static gboolean
+_session_recognized (ActUserManager *manager,
+                     const char     *session_id)
+{
+        GSList *node;
+
+        if (g_hash_table_contains (manager->priv->sessions,
+                                   session_id)) {
+                return TRUE;
+        }
+
+        node = manager->priv->new_sessions;
+        while (node != NULL) {
+                ActUserManagerNewSession *new_session = node->data;
+
+                if (g_strcmp0 (new_session->id, session_id) == 0) {
+                        return TRUE;
+                }
+
+                node = node->next;
+        }
+        return FALSE;
+}
+
+static void
+_add_systemd_session (ActUserManager *manager,
+                      const char     *session_id)
+{
+        load_new_session (manager, session_id);
+}
+
+static void
+_add_new_systemd_sessions (ActUserManager *manager,
+                           GHashTable     *systemd_sessions)
+{
+        GHashTableIter iter;
+        gpointer key, value;
+
+        g_hash_table_iter_init (&iter, systemd_sessions);
+        while (g_hash_table_iter_next (&iter, &key, &value)) {
+                char *session_id = key;
+
+                if (!_session_recognized (manager, session_id)) {
+                        _add_systemd_session (manager, session_id);
+                }
+        }
+}
+
+static void
+_remove_systemd_session (ActUserManager *manager,
+                         const char     *session_id)
+{
+        _remove_session (manager, session_id);
+}
+
+static void
+_remove_stale_systemd_sessions (ActUserManager *manager,
+                                GHashTable     *systemd_sessions)
+{
+        GHashTableIter iter;
+        gpointer key, value;
+        GSList *node