policy: Add parameters to control reconnection

This adds ReconnectAttempts and ReconnectIntervals so platforms can fine
tune the reconnection strategy.

1 files changed, 57 insertions, 28 deletions

diff --git a/plugins/policy.c b/plugins/policy.c
index 45706f62a..809868914 100644
--- a/plugins/policy.c
+++ b/plugins/policy.c
@@ -55,24 +55,26 @@
 #define CT_RETRIES 1
 #define TG_RETRIES CT_RETRIES
 
-/* Tracking of remote services to be auto-reconnected upon link loss */
-
-#define RECONNECT_GIVE_UP (3 * 60)
-#define RECONNECT_TIMEOUT 1
-
 struct reconnect_data {
 	struct btd_device *dev;
 	bool reconnect;
 	GSList *services;
 	guint timer;
 	bool active;
-	time_t start;
-	int timeout;
+	int attempt;
 };
 
 static const char *default_reconnect[] = {
 			HSP_AG_UUID, HFP_AG_UUID, A2DP_SOURCE_UUID, NULL };
 static char **reconnect_uuids = NULL;
+
+static const int default_attempts = 7;
+static int reconnect_attempts = 0;
+
+static const int default_intervals[] = { 1, 2, 4, 8, 16, 32, 64 };
+static int *reconnect_intervals = NULL;
+static int reconnect_intervals_len = 0;
+
 static GSList *reconnects = NULL;
 
 static unsigned int service_id = 0;
@@ -491,8 +493,7 @@ static void target_cb(struct btd_service *service,
 
 static void reconnect_reset(struct reconnect_data *reconnect)
 {
-	reconnect->start = 0;
-	reconnect->timeout = 1;
+	reconnect->attempt = 0;
 
 	if (reconnect->timer > 0) {
 		g_source_remove(reconnect->timer);
@@ -664,9 +665,6 @@ static gboolean reconnect_timeout(gpointer data)
 	/* Mark the GSource as invalid */
 	reconnect->timer = 0;
 
-	/* Increase timeout for the next attempt if this * one fails. */
-	reconnect->timeout *= 2;
-
 	err = btd_device_connect_services(reconnect->dev, reconnect->services);
 	if (err < 0) {
 		error("Reconnecting services failed: %s (%d)",
@@ -676,13 +674,24 @@ static gboolean reconnect_timeout(gpointer data)
 	}
 
 	reconnect->active = true;
-
-	if (!reconnect->start)
-		reconnect->start = time(NULL);
+	reconnect->attempt++;
 
 	return FALSE;
 }
 
+static void reconnect_set_timer(struct reconnect_data *reconnect)
+{
+	static int timeout = 0;
+
+	if (reconnect->attempt < reconnect_intervals_len)
+		timeout = reconnect_intervals[reconnect->attempt];
+
+	DBG("%d seconds", timeout);
+
+	reconnect->timer = g_timeout_add_seconds(timeout, reconnect_timeout,
+								reconnect);
+}
+
 static void disconnect_cb(struct btd_device *dev, uint8_t reason)
 {
 	struct reconnect_data *reconnect;
@@ -699,15 +708,12 @@ static void disconnect_cb(struct btd_device *dev, uint8_t reason)
 	DBG("Device %s identified for auto-reconnection",
 							device_get_path(dev));
 
-	reconnect->timer = g_timeout_add_seconds(reconnect->timeout,
-							reconnect_timeout,
-							reconnect);
+	reconnect_set_timer(reconnect);
 }
 
 static void conn_fail_cb(struct btd_device *dev, uint8_t status)
 {
 	struct reconnect_data *reconnect;
-	time_t duration;
 
 	DBG("status %u", status);
 
@@ -726,16 +732,13 @@ static void conn_fail_cb(struct btd_device *dev, uint8_t status)
 		return;
 	}
 
-	/* Give up if we've tried for too long */
-	duration = time(NULL) - reconnect->start;
-	if (duration + reconnect->timeout >= RECONNECT_GIVE_UP) {
+	/* Reset if ReconnectAttempts was reached */
+	if (reconnect->attempt == reconnect_attempts) {
 		reconnect_reset(reconnect);
 		return;
 	}
 
-	reconnect->timer = g_timeout_add_seconds(reconnect->timeout,
-							reconnect_timeout,
-							reconnect);
+	reconnect_set_timer(reconnect);
 }
 
 static int policy_init(void)
@@ -748,6 +751,11 @@ static int policy_init(void)
 	conf = btd_get_main_conf();
 	if (!conf) {
 		reconnect_uuids = g_strdupv((char **) default_reconnect);
+		reconnect_attempts = default_attempts;
+		reconnect_intervals_len = sizeof(default_intervals) /
+						sizeof(*reconnect_intervals);
+		reconnect_intervals = g_memdup(default_intervals,
+						reconnect_intervals_len);
 		goto add_cb;
 	}
 
@@ -755,12 +763,31 @@ static int policy_init(void)
 							"ReconnectUUIDs",
 							NULL, &gerr);
 	if (gerr) {
-		g_error_free(gerr);
+		g_clear_error(&gerr);
 		reconnect_uuids = g_strdupv((char **) default_reconnect);
-		goto add_cb;
 	}
+
+	reconnect_attempts = g_key_file_get_integer(conf, "Policy",
+							"ReconnectAttempts",
+							&gerr);
+	if (gerr) {
+		g_clear_error(&gerr);
+		reconnect_attempts = default_attempts;
+	}
+
+	reconnect_intervals = g_key_file_get_integer_list(conf, "Policy",
+					"ReconnectIntervals",
+					(size_t *) &reconnect_intervals_len,
+					&gerr);
+	if (gerr) {
+		g_clear_error(&gerr);
+		reconnect_intervals_len = sizeof(default_intervals);
+		reconnect_intervals = g_memdup(default_intervals,
+						reconnect_intervals_len);
+	}
+
 add_cb:
-	if (reconnect_uuids && reconnect_uuids[0]) {
+	if (reconnect_uuids && reconnect_uuids[0] && reconnect_attempts) {
 		btd_add_disconnect_cb(disconnect_cb);
 		btd_add_conn_fail_cb(conn_fail_cb);
 	}
@@ -776,6 +803,8 @@ static void policy_exit(void)
 	if (reconnect_uuids)
 		g_strfreev(reconnect_uuids);
 
+	g_free(reconnect_intervals);
+
 	g_slist_free_full(reconnects, reconnect_destroy);
 
 	g_slist_free_full(devices, policy_remove);