JACK: Fail context init if JACK is unusable.

mini_al.h

@@ -12173,14 +12173,11 @@ typedef const char*        (* mal_jack_port_name_proc)               (const mal_
 typedef void*              (* mal_jack_port_get_buffer_proc)         (mal_jack_port_t* port, mal_jack_nframes_t nframes);
 typedef void               (* mal_jack_free_proc)                    (void* ptr);
 
-mal_result mal_context_open_client__jack(mal_context* pContext, mal_device_type type, const mal_device_id* pDeviceID, mal_jack_client_t** ppClient)
+mal_result mal_context_open_client__jack(mal_context* pContext, mal_jack_client_t** ppClient)
 {
     mal_assert(pContext != NULL);
     mal_assert(ppClient != NULL);
 
-    (void)type;
-    (void)pDeviceID;
-
     if (ppClient) {
         *ppClient = NULL;
     }
@@ -12193,7 +12190,7 @@ mal_result mal_context_open_client__jack(mal_context* pContext, mal_device_type
     mal_jack_status_t status;
     mal_jack_client_t* pClient = ((mal_jack_client_open_proc)pContext->jack.jack_client_open)(clientName, (pContext->config.jack.tryStartServer) ? 0 : mal_JackNoStartServer, &status, NULL);
     if (pClient == NULL) {
-        return mal_context_post_error(pContext, NULL, MAL_LOG_LEVEL_ERROR, "[JACK] Failed to open client.", MAL_FAILED_TO_OPEN_BACKEND_DEVICE);
+        return MAL_FAILED_TO_OPEN_BACKEND_DEVICE;
     }
 
     if (ppClient) {
@@ -12263,9 +12260,9 @@ mal_result mal_context_get_device_info__jack(mal_context* pContext, mal_device_t
 
     // The channel count and sample rate can only be determined by opening the device.
     mal_jack_client_t* pClient;
-    mal_result result = mal_context_open_client__jack(pContext, deviceType, pDeviceID, &pClient);
+    mal_result result = mal_context_open_client__jack(pContext, &pClient);
     if (result != MAL_SUCCESS) {
-        return result;
+        return mal_context_post_error(pContext, NULL, MAL_LOG_LEVEL_ERROR, "[JACK] Failed to open client.", MAL_FAILED_TO_OPEN_BACKEND_DEVICE);
     }
 
     pDeviceInfo->minSampleRate = ((mal_jack_get_sample_rate_proc)pContext->jack.jack_get_sample_rate)((mal_jack_client_t*)pClient);
@@ -12375,6 +12372,16 @@ mal_result mal_context_init__jack(mal_context* pContext)
     pContext->onEnumDevices   = mal_context_enumerate_devices__jack;
     pContext->onGetDeviceInfo = mal_context_get_device_info__jack;
 
+
+    // Getting here means the JACK library is installed, but it doesn't necessarily mean it's usable. We need to quickly test this by connecting
+    // a temporary client.
+    mal_jack_client_t* pDummyClient;
+    mal_result result = mal_context_open_client__jack(pContext, &pDummyClient);
+    if (result != MAL_SUCCESS) {
+        return MAL_NO_BACKEND;
+    }
+
+    ((mal_jack_client_close_proc)pContext->jack.jack_client_close)((mal_jack_client_t*)pDummyClient);
     return MAL_SUCCESS;
 }
 
@@ -12488,9 +12495,9 @@ mal_result mal_device_init__jack(mal_context* pContext, mal_device_type type, ma
 
 
     // Open the client.
-    mal_result result = mal_context_open_client__jack(pContext, type, pDeviceID, (mal_jack_client_t**)&pDevice->jack.pClient);
+    mal_result result = mal_context_open_client__jack(pContext, (mal_jack_client_t**)&pDevice->jack.pClient);
     if (result != MAL_SUCCESS) {
-        return result;
+        return mal_post_error(pDevice, MAL_LOG_LEVEL_ERROR, "[JACK] Failed to open client.", MAL_FAILED_TO_OPEN_BACKEND_DEVICE);
     }
 
     // Callbacks.