From 7aae8c45ec504523b525688b098cd28af051f2a1 Mon Sep 17 00:00:00 2001
From: Pauli Virtanen <pav@iki.fi>
Date: Thu, 25 May 2023 19:12:12 +0300
Subject: [PATCH] bluez5: do not delay transport release if it is not active

Transport release should not be delayed if it is not active, since the
fd cannot be used any more, and the transport needs to be reacquired to
get a working fd.

Fixes reacquiring transports if the remote side causes them to become
inactive.
---
 spa/plugins/bluez5/bluez5-dbus.c | 69 +++++++++++++++++++++++---------
 1 file changed, 50 insertions(+), 19 deletions(-)

diff --git a/spa/plugins/bluez5/bluez5-dbus.c b/spa/plugins/bluez5/bluez5-dbus.c
index b14e60bcf..a6d0fd660 100644
--- a/spa/plugins/bluez5/bluez5-dbus.c
+++ b/spa/plugins/bluez5/bluez5-dbus.c
@@ -203,6 +203,7 @@ static int spa_bt_transport_stop_volume_timer(struct spa_bt_transport *transport
 static int spa_bt_transport_start_volume_timer(struct spa_bt_transport *transport);
 static int spa_bt_transport_stop_release_timer(struct spa_bt_transport *transport);
 static int spa_bt_transport_start_release_timer(struct spa_bt_transport *transport);
+static void spa_bt_transport_commit_release_timer(struct spa_bt_transport *transport);
 
 static int device_start_timer(struct spa_bt_device *device);
 static int device_stop_timer(struct spa_bt_device *device);
@@ -2589,6 +2590,13 @@ void spa_bt_transport_set_state(struct spa_bt_transport *transport, enum spa_bt_
 		if (state >= SPA_BT_TRANSPORT_STATE_PENDING && old < SPA_BT_TRANSPORT_STATE_PENDING)
 			transport_sync_volume(transport);
 
+		if (state < SPA_BT_TRANSPORT_STATE_ACTIVE) {
+			/* If transport becomes inactive, do any pending releases
+			 * immediately, since the fd is not usable any more.
+			 */
+			spa_bt_transport_commit_release_timer(transport);
+		}
+
 		if (state == SPA_BT_TRANSPORT_STATE_ERROR) {
 			uint64_t now = get_time_now(monitor);
 
@@ -2719,6 +2727,27 @@ int spa_bt_transport_acquire(struct spa_bt_transport *transport, bool optional)
 	return res;
 }
 
+static void spa_bt_transport_do_release(struct spa_bt_transport *transport)
+{
+	struct spa_bt_monitor *monitor = transport->monitor;
+
+	spa_assert(transport->acquire_refcount >= 1);
+	spa_assert(transport->acquired);
+
+	if (transport->acquire_refcount == 1) {
+		if (!transport->keepalive) {
+			spa_bt_transport_impl(transport, release, 0);
+			transport->acquired = false;
+		} else {
+			spa_log_debug(monitor->log, "transport %p: keepalive %s on release",
+					transport, transport->path);
+		}
+	} else {
+		spa_log_debug(monitor->log, "transport %p: delayed decref %s", transport, transport->path);
+	}
+	transport->acquire_refcount -= 1;
+}
+
 int spa_bt_transport_release(struct spa_bt_transport *transport)
 {
 	struct spa_bt_monitor *monitor = transport->monitor;
@@ -2736,8 +2765,15 @@ int spa_bt_transport_release(struct spa_bt_transport *transport)
 	spa_assert(transport->acquire_refcount == 1);
 	spa_assert(transport->acquired);
 
-	/* Postpone transport releases, since we might need it again soon */
-	return spa_bt_transport_start_release_timer(transport);
+	/* Postpone active transport releases, since we might need it again soon.
+	 * If not active, release now since it has to be reacquired before using again.
+	 */
+	if (transport->state == SPA_BT_TRANSPORT_STATE_ACTIVE) {
+		return spa_bt_transport_start_release_timer(transport);
+	} else {
+		spa_bt_transport_do_release(transport);
+		return 0;
+	}
 }
 
 static int spa_bt_transport_release_now(struct spa_bt_transport *transport)
@@ -2808,25 +2844,9 @@ static int stop_timeout_timer(struct spa_bt_monitor *monitor, struct spa_source
 static void spa_bt_transport_release_timer_event(struct spa_source *source)
 {
 	struct spa_bt_transport *transport = source->data;
-	struct spa_bt_monitor *monitor = transport->monitor;
-
-	spa_assert(transport->acquire_refcount >= 1);
-	spa_assert(transport->acquired);
 
 	spa_bt_transport_stop_release_timer(transport);
-
-	if (transport->acquire_refcount == 1) {
-		if (!transport->keepalive) {
-			spa_bt_transport_impl(transport, release, 0);
-			transport->acquired = false;
-		} else {
-			spa_log_debug(monitor->log, "transport %p: keepalive %s on release",
-					transport, transport->path);
-		}
-	} else {
-		spa_log_debug(monitor->log, "transport %p: delayed decref %s", transport, transport->path);
-	}
-	transport->acquire_refcount -= 1;
+	spa_bt_transport_do_release(transport);
 }
 
 static int spa_bt_transport_start_release_timer(struct spa_bt_transport *transport)
@@ -2842,6 +2862,17 @@ static int spa_bt_transport_stop_release_timer(struct spa_bt_transport *transpor
 	return stop_timeout_timer(transport->monitor, &transport->release_timer);
 }
 
+static void spa_bt_transport_commit_release_timer(struct spa_bt_transport *transport)
+{
+	struct spa_bt_monitor *monitor = transport->monitor;
+
+	/* Do release now if it is pending */
+	if (transport->release_timer.data) {
+		spa_log_debug(monitor->log, "transport %p: commit pending release", transport);
+		spa_bt_transport_release_timer_event(&transport->release_timer);
+	}
+}
+
 static void spa_bt_transport_volume_changed(struct spa_bt_transport *transport)
 {
 	struct spa_bt_monitor *monitor = transport->monitor;