daemon: Fix boot delay

commit 836a9135fe2d8fdc7d6de3a6d11fb9a5fd05f926 made accountsservice
reload wtmp less aggressively.

Unfortunately, if wtmp is modified during boot, that added latency
can delay the user list getting loaded.

This commit addresses the problem by tracking how pressing the queued
reload operation is, and makes it happen sooner if a higher priority
request comes in.

1 files changed, 25 insertions, 0 deletions

diff --git a/src/daemon.c b/src/daemon.c
index 151f294..aa9d050 100644
--- a/src/daemon.c
+++ b/src/daemon.c
@@ -70,6 +70,14 @@ typedef enum
         DISPLAY_MANAGER_TYPE_LIGHTDM
 } DisplayManagerType;
 
+typedef enum
+{
+        USER_RELOAD_TYPE_NONE = 0,
+        USER_RELOAD_TYPE_IMMEDIATELY,
+        USER_RELOAD_TYPE_SOON,
+        USER_RELOAD_TYPE_EVENTUALLY
+} UserReloadType;
+
 typedef struct
 {
         GDBusConnection *bus_connection;
@@ -88,7 +96,9 @@ typedef struct
 
         GQueue          *pending_list_cached_users;
 
+        UserReloadType   reload_type;
         guint            reload_id;
+
         guint            autologin_id;
 
         PolkitAuthority *authority;
@@ -625,6 +635,7 @@ reload_users_timeout (Daemon *daemon)
 
         reload_users (daemon);
         priv->reload_id = 0;
+        priv->reload_type = USER_RELOAD_TYPE_NONE;
 
         g_queue_foreach (priv->pending_list_cached_users,
                          (GFunc) finish_list_cached_users, NULL);
@@ -698,6 +709,7 @@ queue_reload_users_eventually (Daemon *daemon)
          * and out in a continuous loop.
          */
         priv->reload_id = g_timeout_add_seconds (10, (GSourceFunc) reload_users_timeout, daemon);
+        priv->reload_type = USER_RELOAD_TYPE_EVENTUALLY;
 }
 
 static void
@@ -705,6 +717,11 @@ queue_reload_users_soon (Daemon *daemon)
 {
         DaemonPrivate *priv = daemon_get_instance_private (daemon);
 
+        if (priv->reload_type > USER_RELOAD_TYPE_SOON) {
+                g_source_remove (priv->reload_id);
+                priv->reload_id = 0;
+        }
+
         if (priv->reload_id > 0) {
                 return;
         }
@@ -713,6 +730,7 @@ queue_reload_users_soon (Daemon *daemon)
          * /etc/shadow are changed at the same time, or repeatedly.
          */
         priv->reload_id = g_timeout_add (500, (GSourceFunc) reload_users_timeout, daemon);
+        priv->reload_type = USER_RELOAD_TYPE_SOON;
 }
 
 static void
@@ -720,11 +738,17 @@ queue_reload_users (Daemon *daemon)
 {
         DaemonPrivate *priv = daemon_get_instance_private (daemon);
 
+        if (priv->reload_type > USER_RELOAD_TYPE_IMMEDIATELY) {
+                g_source_remove (priv->reload_id);
+                priv->reload_id = 0;
+        }
+
         if (priv->reload_id > 0) {
                 return;
         }
 
         priv->reload_id = g_idle_add ((GSourceFunc) reload_users_timeout, daemon);
+        priv->reload_type = USER_RELOAD_TYPE_IMMEDIATELY;
 }
 
 static void
@@ -1147,6 +1171,7 @@ daemon_list_cached_users (AccountsAccounts      *accounts,
         if (priv->reload_id > 0) {
                 /* reload pending -- finish call in reload_users_timeout */
                 g_queue_push_tail (priv->pending_list_cached_users, data);
+                queue_reload_users (daemon);
         } else {
                 finish_list_cached_users (data);
         }