core: determine whether connection timestamps are set or not

Currently there's no way to differentiate between a connection that has
never been activated, and a connection that has never been *successfully*
activated.  In both cases nm_settings_connection_get_timestamp() returns
zero.  But it's useful to know whether a connection hasn't even been
tried yet, so enhance the timestamp code to return whether or not the
timestamp has been found in the timestamp cache or not, and make the
NMDevice core set an explict timestamp of 0 if the connection failed
on the first attempt.

We'll use this later to conditionally autoconnect WiFi connections
depending on whether they've ever successfully connected or not, but
still allow preloaded connections without a timestamp to autoconnect
as they always have.

4 files changed, 46 insertions, 22 deletions

diff --git a/src/nm-device.c b/src/nm-device.c
index f20b5a32..72b68907 100644
--- a/src/nm-device.c
+++ b/src/nm-device.c
@@ -4639,6 +4639,18 @@ nm_device_state_changed (NMDevice *device,
 		             "Activation (%s) failed for connection '%s'",
 		             nm_device_get_iface (device),
 		             nm_connection_get_id (connection));
+
+		/* If the connection doesn't yet have a timestamp, set it to zero so that
+		 * we can distinguish between connections we've tried to activate and have
+		 * failed (zero timestamp), connections that succeeded (non-zero timestamp),
+		 * and those we haven't tried yet (no timestamp).
+		 */
+		if (!nm_settings_connection_get_timestamp (NM_SETTINGS_CONNECTION (connection), NULL)) {
+			nm_settings_connection_update_timestamp (NM_SETTINGS_CONNECTION (connection),
+			                                         (guint64) 0,
+			                                         TRUE);
+		}
+
 		/* Schedule the transition to DISCONNECTED.  The device can't transition
 		 * immediately because we can't change states again from the state
 		 * handler for a variety of reasons.
diff --git a/src/settings/nm-settings-connection.c b/src/settings/nm-settings-connection.c
index ddc758c7..c1c55b05 100644
--- a/src/settings/nm-settings-connection.c
+++ b/src/settings/nm-settings-connection.c
@@ -16,7 +16,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * (C) Copyright 2008 Novell, Inc.
- * (C) Copyright 2008 - 2011 Red Hat, Inc.
+ * (C) Copyright 2008 - 2012 Red Hat, Inc.
  */
 
 #include "config.h"
@@ -107,6 +107,7 @@ typedef struct {
 	NMConnection *agent_secrets;
 
 	guint64 timestamp;   /* Up-to-date timestamp of connection use */
+	gboolean timestamp_set;
 	GHashTable *seen_bssids; /* Up-to-date BSSIDs that's been seen for the connection */
 } NMSettingsConnectionPrivate;
 
@@ -1061,7 +1062,7 @@ get_settings_auth_cb (NMSettingsConnection *self,
 		GHashTable *settings;
 		NMConnection *dupl_con;
 		NMSettingConnection *s_con;
-		guint64 timestamp;
+		guint64 timestamp = 0;
 
 		dupl_con = nm_connection_duplicate (NM_CONNECTION (self));
 		g_assert (dupl_con);
@@ -1072,7 +1073,7 @@ get_settings_auth_cb (NMSettingsConnection *self,
 		 * timestamps are kept track of in a private variable. So, substitute
 		 * timestamp property with the real one here before returning the settings.
 		 */
-		timestamp = nm_settings_connection_get_timestamp (self);
+		nm_settings_connection_get_timestamp (self, &timestamp);
 		if (timestamp) {
 			s_con = nm_connection_get_setting_connection (NM_CONNECTION (dupl_con));
 			g_assert (s_con);
@@ -1403,18 +1404,23 @@ nm_settings_connection_signal_remove (NMSettingsConnection *self)
 /**
  * nm_settings_connection_get_timestamp:
  * @connection: the #NMSettingsConnection
+ * @out_timestamp: the connection's timestamp
  *
- * Returns current connection's timestamp.
+ * Returns the time (in seconds since the Unix epoch) when the connection
+ * was last successfully activated.
  *
- * Returns: timestamp of the last connection use (0 when it's not used)
+ * Returns: %TRUE if the timestamp has ever been set, otherwise %FALSE.
  **/
-guint64
-nm_settings_connection_get_timestamp (NMSettingsConnection *connection)
+gboolean
+nm_settings_connection_get_timestamp (NMSettingsConnection *connection,
+                                      guint64 *out_timestamp)
 {
 	g_return_val_if_fail (connection != NULL, 0);
 	g_return_val_if_fail (NM_IS_SETTINGS_CONNECTION (connection), 0);
 
-	return NM_SETTINGS_CONNECTION_GET_PRIVATE (connection)->timestamp;
+	if (out_timestamp)
+		*out_timestamp = NM_SETTINGS_CONNECTION_GET_PRIVATE (connection)->timestamp;
+	return NM_SETTINGS_CONNECTION_GET_PRIVATE (connection)->timestamp_set;
 }
 
 /**
@@ -1440,6 +1446,7 @@ nm_settings_connection_update_timestamp (NMSettingsConnection *connection,
 
 	/* Update timestamp in private storage */
 	priv->timestamp = timestamp;
+	priv->timestamp_set = TRUE;
 
 	if (flush_to_disk == FALSE)
 		return;
@@ -1497,9 +1504,10 @@ nm_settings_connection_read_and_fill_timestamp (NMSettingsConnection *connection
 	}
 
 	/* Update connection's timestamp */
-	if (!err)
+	if (!err) {
 		priv->timestamp = timestamp;
-	else {
+		priv->timestamp_set = TRUE;
+	} else {
 		nm_log_dbg (LOGD_SETTINGS, "failed to read connection timestamp for '%s': (%d) %s",
 		            connection_uuid, err->code, err->message);
 		g_clear_error (&err);
diff --git a/src/settings/nm-settings-connection.h b/src/settings/nm-settings-connection.h
index 9a0e866c..73ca8192 100644
--- a/src/settings/nm-settings-connection.h
+++ b/src/settings/nm-settings-connection.h
@@ -122,7 +122,8 @@ gboolean nm_settings_connection_check_permission (NMSettingsConnection *self,
 
 void nm_settings_connection_signal_remove (NMSettingsConnection *self);
 
-guint64 nm_settings_connection_get_timestamp (NMSettingsConnection *connection);
+gboolean nm_settings_connection_get_timestamp (NMSettingsConnection *connection,
+                                               guint64 *out_timestamp);
 
 void nm_settings_connection_update_timestamp (NMSettingsConnection *connection,
                                               guint64 timestamp,
diff --git a/src/settings/nm-settings.c b/src/settings/nm-settings.c
index ea0ff31a..1d3c74f6 100644
--- a/src/settings/nm-settings.c
+++ b/src/settings/nm-settings.c
@@ -287,7 +287,7 @@ connection_sort (gconstpointer pa, gconstpointer pb)
 	NMSettingConnection *con_a;
 	NMConnection *b = NM_CONNECTION (pb);
 	NMSettingConnection *con_b;
-	guint64 ts_a, ts_b;
+	guint64 ts_a = 0, ts_b = 0;
 
 	con_a = nm_connection_get_setting_connection (a);
 	g_assert (con_a);
@@ -300,8 +300,8 @@ connection_sort (gconstpointer pa, gconstpointer pb)
 		return 1;
 	}
 
-	ts_a = nm_settings_connection_get_timestamp (NM_SETTINGS_CONNECTION (pa));
-	ts_b = nm_settings_connection_get_timestamp (NM_SETTINGS_CONNECTION (pb));
+	nm_settings_connection_get_timestamp (NM_SETTINGS_CONNECTION (pa), &ts_a);
+	nm_settings_connection_get_timestamp (NM_SETTINGS_CONNECTION (pb), &ts_b);
 	if (ts_a > ts_b)
 		return -1;
 	else if (ts_a == ts_b)
@@ -1657,7 +1657,7 @@ best_connection_sort (gconstpointer a, gconstpointer b, gpointer user_data)
 {
 	NMSettingsConnection *ac = (NMSettingsConnection *) a;
 	NMSettingsConnection *bc = (NMSettingsConnection *) b;
-	guint64 ats, bts;
+	guint64 ats = 0, bts = 0;
 
 	if (!ac && bc)
 		return -1;
@@ -1669,8 +1669,8 @@ best_connection_sort (gconstpointer a, gconstpointer b, gpointer user_data)
 	g_assert (ac && bc);
 
 	/* In the future we may use connection priorities in addition to timestamps */
-	ats = nm_settings_connection_get_timestamp (ac);
-	bts = nm_settings_connection_get_timestamp (bc);
+	nm_settings_connection_get_timestamp (ac, &ats);
+	nm_settings_connection_get_timestamp (bc, &bts);
 
 	if (ats < bts)
 		return -1;
@@ -1697,6 +1697,8 @@ get_best_connections (NMConnectionProvider *provider,
 
 	g_hash_table_iter_init (&iter, priv->connections);
 	while (g_hash_table_iter_next (&iter, NULL, (gpointer) &connection)) {
+		guint64 cur_ts = 0;
+
 		if (ctype1 && !nm_connection_is_type (NM_CONNECTION (connection), ctype1))
 			continue;
 		if (ctype2 && !nm_connection_is_type (NM_CONNECTION (connection), ctype2))
@@ -1705,10 +1707,11 @@ get_best_connections (NMConnectionProvider *provider,
 			continue;
 
 		/* Don't bother with a connection that's older than the oldest one in the list */
-		if (   max_requested
-		    && added >= max_requested
-		    && nm_settings_connection_get_timestamp (connection) <= oldest)
-			continue;
+		if (max_requested && added >= max_requested) {
+		    nm_settings_connection_get_timestamp (connection, &cur_ts);
+		    if (cur_ts <= oldest)
+				continue;
+		}
 
 		/* List is sorted with oldest first */
 		sorted = g_slist_insert_sorted_with_data (sorted, connection, best_connection_sort, NULL);
@@ -1720,7 +1723,7 @@ get_best_connections (NMConnectionProvider *provider,
 			added--;
 		}
 
-		oldest = nm_settings_connection_get_timestamp (NM_SETTINGS_CONNECTION (sorted->data));
+		nm_settings_connection_get_timestamp (NM_SETTINGS_CONNECTION (sorted->data), &oldest);
 	}
 
 	return g_slist_reverse (sorted);