Fail gracefully when a plugin can't be instantiated (instead of crashing on assert failure).

git-svn-id: http://svn.drobilla.net/lad/slv2@559 a436a847-0d15-0410-975c-d299462d15a1

1 files changed, 15 insertions, 11 deletions

diff --git a/src/plugininstance.c b/src/plugininstance.c
index be2252c..62b4c7d 100644
--- a/src/plugininstance.c
+++ b/src/plugininstance.c
@@ -99,20 +99,21 @@ slv2_plugin_instantiate(SLV2Plugin               plugin,
 		}
 	}
 
-	assert(result);
-	assert(slv2_plugin_get_num_ports(plugin) > 0);
+	if (result) {
+		assert(slv2_plugin_get_num_ports(plugin) > 0);
+
+		// Failed to instantiate
+		if (result->lv2_handle == NULL) {
+			//printf("Failed to instantiate %s\n", plugin->plugin_uri);
+			free(result);
+			return NULL;
+		}
 
-	// Failed to instantiate
-	if (result->lv2_handle == NULL) {
-		//printf("Failed to instantiate %s\n", plugin->plugin_uri);
-		free(result);
-		return NULL;
+		// "Connect" all ports to NULL (catches bugs)
+		for (uint32_t i=0; i < slv2_plugin_get_num_ports(plugin); ++i)
+			result->lv2_descriptor->connect_port(result->lv2_handle, i, NULL);
 	}
 
-	// "Connect" all ports to NULL (catches bugs)
-	for (uint32_t i=0; i < slv2_plugin_get_num_ports(plugin); ++i)
-		result->lv2_descriptor->connect_port(result->lv2_handle, i, NULL);
-	
 	if (local_host_features)
 		free(host_features);
 
@@ -123,6 +124,9 @@ slv2_plugin_instantiate(SLV2Plugin               plugin,
 void
 slv2_instance_free(SLV2Instance instance)
 {
+	if (!instance)
+		return;
+
 	struct _Instance* i = (struct _Instance*)instance;
 	i->lv2_descriptor->cleanup(i->lv2_handle);
 	i->lv2_descriptor = NULL;