bluetooth: Introduce a can_be_supported API for A2DP codecs

This API internally checks if a requested codec can be supported on the
system. This is especially required for codecs supported via GStreamer
where the availability of a plugin decides if the said codec can be
supported.

This will be used to prevent registration of a codec which the remote
endpoint device might be able to support, but, PulseAudio can't as the
codec is not available on the system due to the absence of a plugin.
We can also prevent listing or switching to an unavailable codec.

Note that the codec negotiation happens with the bluez stack even before
a device is connected. Because of this, we need to make sure that gst_init
is called before checking for the availability of a plugin. Since
module-bluez5-device gets loaded only after a connection to the device
has been established, doing the gst_init in that or one of the bluetooth
modules is not feasible.

Part-of: <https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/merge_requests/440>

1 files changed, 0 insertions, 7 deletions

diff --git a/src/modules/bluetooth/a2dp-codec-gst.c b/src/modules/bluetooth/a2dp-codec-gst.c
index c714c1d34..958f6ec20 100644
--- a/src/modules/bluetooth/a2dp-codec-gst.c
+++ b/src/modules/bluetooth/a2dp-codec-gst.c
@@ -575,15 +575,8 @@ fail:
 
 void *gst_codec_init(enum a2dp_codec_type codec_type, const uint8_t *config_buffer, uint8_t config_size, pa_sample_spec *ss) {
     struct gst_info *info = NULL;
-    GError *error = NULL;
     bool ret;
 
-    if (!gst_init_check(NULL, NULL, &error)) {
-        pa_log_error("Could not initialise GStreamer: %s", error->message);
-        g_error_free(error);
-        goto fail;
-    }
-
     info = pa_xnew0(struct gst_info, 1);
     pa_assert(info);