bluetooth: use helper to set multiple transport object attributes

For mSBC to work correctly the following must be set correctly
- codec object
- transport write method
- transport setsockopt method

Use helper method to set all three simultaneously.
Static configuration structure may be cleaner solution.

Part-of: <https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/merge_requests/507>

src/modules/bluetooth/backend-native.c

@@ -599,19 +599,16 @@ static bool hfp_rfcomm_handle(int fd, pa_bluetooth_transport *t, const char *buf
             c->state = 4;
         } else {
             c->state = 5;
-            t->bt_codec = pa_bluetooth_get_hf_codec("CVSD");
-            t->setsockopt = NULL;
+            pa_bluetooth_transport_reconfigure(t, pa_bluetooth_get_hf_codec("CVSD"), sco_transport_write, NULL);
             transport_put(t);
         }
 
         return false;
     } else if (sscanf(buf, "AT+BCS=%d", &val)) {
         if (val == 1) {
-            t->bt_codec = pa_bluetooth_get_hf_codec("CVSD");
-            t->setsockopt = NULL;
+            pa_bluetooth_transport_reconfigure(t, pa_bluetooth_get_hf_codec("CVSD"), sco_transport_write, NULL);
         } else if (val == 2) {
-            t->bt_codec = pa_bluetooth_get_hf_codec("mSBC");
-            t->setsockopt = sco_setsockopt_enable_bt_voice;
+            pa_bluetooth_transport_reconfigure(t, pa_bluetooth_get_hf_codec("mSBC"), sco_transport_write, sco_setsockopt_enable_bt_voice);
         } else
             pa_assert_not_reached();
 
@@ -849,8 +846,6 @@ static DBusMessage *profile_new_connection(DBusConnection *conn, DBusMessage *m,
 
     t->acquire = sco_acquire_cb;
     t->release = sco_release_cb;
-    t->write = sco_transport_write;
-    t->bt_codec = pa_bluetooth_get_hf_codec("CVSD");
     t->destroy = transport_destroy;
 
     /* If PA is the HF/HS we are in control of volume attenuation and
@@ -872,6 +867,8 @@ static DBusMessage *profile_new_connection(DBusConnection *conn, DBusMessage *m,
         t->set_source_volume = set_source_volume;
     }
 
+    pa_bluetooth_transport_reconfigure(t, pa_bluetooth_get_hf_codec("CVSD"), sco_transport_write, NULL);
+
     trd = pa_xnew0(struct transport_data, 1);
     trd->rfcomm_fd = fd;
     trd->mainloop = b->core->mainloop;

src/modules/bluetooth/backend-ofono.c

@@ -227,8 +227,7 @@ static int card_acquire(struct hf_audio_card *card) {
             close(fd);
             return -1;
         }
-        card->transport->bt_codec = pa_bluetooth_get_hf_codec("CVSD");
-        card->transport->setsockopt = NULL;
+        pa_bluetooth_transport_reconfigure(card->transport, pa_bluetooth_get_hf_codec("CVSD"), sco_transport_write, NULL);
         card->fd = fd;
         return 0;
     }
@@ -410,8 +409,8 @@ static void hf_audio_agent_card_found(pa_bluetooth_backend *backend, const char
     card->transport = pa_bluetooth_transport_new(d, backend->ofono_bus_id, path, p, NULL, 0);
     card->transport->acquire = hf_audio_agent_transport_acquire;
     card->transport->release = hf_audio_agent_transport_release;
-    card->transport->write = sco_transport_write;
     card->transport->userdata = card;
+    pa_bluetooth_transport_reconfigure(card->transport, pa_bluetooth_get_hf_codec("CVSD"), sco_transport_write, NULL);
 
     pa_bluetooth_transport_put(card->transport);
     pa_hashmap_put(backend->cards, card->path, card);
@@ -696,8 +695,7 @@ static DBusMessage *hf_audio_agent_new_connection(DBusConnection *c, DBusMessage
 
     card->connecting = false;
     card->fd = fd;
-    card->transport->bt_codec = pa_bluetooth_get_hf_codec("CVSD");
-    card->transport->setsockopt = NULL;
+    pa_bluetooth_transport_reconfigure(card->transport, pa_bluetooth_get_hf_codec("CVSD"), sco_transport_write, NULL);
 
     pa_bluetooth_transport_set_state(card->transport, PA_BLUETOOTH_TRANSPORT_STATE_PLAYING);
 

src/modules/bluetooth/bluez5-util.c

@@ -184,6 +184,22 @@ pa_bluetooth_transport *pa_bluetooth_transport_new(pa_bluetooth_device *d, const
     return t;
 }
 
+void pa_bluetooth_transport_reconfigure(pa_bluetooth_transport *t, const pa_a2dp_codec *bt_codec,
+                                        pa_bluetooth_transport_write_cb write_cb, pa_bluetooth_transport_setsockopt_cb setsockopt_cb) {
+    pa_assert(t);
+
+    t->bt_codec = bt_codec;
+
+    t->write = write_cb;
+    t->setsockopt = setsockopt_cb;
+
+    /* reset stream write type hint */
+    t->stream_write_type = 0;
+
+    /* reset SCO MTU adjustment hint */
+    t->last_read_size = 0;
+}
+
 static const char *transport_state_to_string(pa_bluetooth_transport_state_t state) {
     switch(state) {
         case PA_BLUETOOTH_TRANSPORT_STATE_DISCONNECTED:
@@ -1945,10 +1961,9 @@ static DBusMessage *endpoint_set_configuration(DBusConnection *conn, DBusMessage
     dbus_message_unref(r);
 
     t = pa_bluetooth_transport_new(d, sender, path, p, config, size);
-    t->bt_codec = a2dp_codec;
     t->acquire = bluez5_transport_acquire_cb;
     t->release = bluez5_transport_release_cb;
-    t->write = a2dp_transport_write;
+    pa_bluetooth_transport_reconfigure(t, a2dp_codec, a2dp_transport_write, NULL);
     pa_bluetooth_transport_put(t);
 
     pa_log_debug("Transport %s available for profile %s", t->path, pa_bluetooth_profile_to_string(t->profile));

src/modules/bluetooth/bluez5-util.h

@@ -182,6 +182,9 @@ static inline void pa_bluetooth_native_backend_enable_shared_profiles(pa_bluetoo
 pa_bluetooth_transport *pa_bluetooth_transport_new(pa_bluetooth_device *d, const char *owner, const char *path,
                                                    pa_bluetooth_profile_t p, const uint8_t *config, size_t size);
 
+void pa_bluetooth_transport_reconfigure(pa_bluetooth_transport *t, const pa_a2dp_codec *bt_codec,
+                                        pa_bluetooth_transport_write_cb write_cb, pa_bluetooth_transport_setsockopt_cb setsockopt_cb);
+
 void pa_bluetooth_transport_set_state(pa_bluetooth_transport *t, pa_bluetooth_transport_state_t state);
 void pa_bluetooth_transport_put(pa_bluetooth_transport *t);
 void pa_bluetooth_transport_unlink(pa_bluetooth_transport *t);