LV2: check required feature and options

When discovering LV2 plugins, verify if a plugin's required features
and required options can be be satisfied.

This replaces a previous blacklist with a whitelist of supported
features/options.

1 files changed, 52 insertions, 26 deletions

diff --git a/libs/ardour/lv2_plugin.cc b/libs/ardour/lv2_plugin.cc
index 042bc92200..fe2bde8d1d 100644
--- a/libs/ardour/lv2_plugin.cc
+++ b/libs/ardour/lv2_plugin.cc
@@ -82,6 +82,7 @@
 #include "lv2/lv2plug.in/ns/extensions/units/units.h"
 #include "lv2/lv2plug.in/ns/ext/patch/patch.h"
 #include "lv2/lv2plug.in/ns/ext/port-groups/port-groups.h"
+#include "lv2/lv2plug.in/ns/ext/parameters/parameters.h"
 #ifdef HAVE_LV2_1_2_0
 #include "lv2/lv2plug.in/ns/ext/buf-size/buf-size.h"
 #include "lv2/lv2plug.in/ns/ext/options/options.h"
@@ -180,6 +181,7 @@ public:
 	LilvNode* units_midiNote;
 	LilvNode* patch_writable;
 	LilvNode* patch_Message;
+	LilvNode* opts_requiredOptions;
 #ifdef HAVE_LV2_1_2_0
 	LilvNode* bufz_powerOf2BlockLength;
 	LilvNode* bufz_fixedBlockLength;
@@ -624,22 +626,6 @@ LV2Plugin::init(const void* c_plugin, samplecnt_t rate)
 		throw failed_constructor();
 	}
 
-#ifdef HAVE_LV2_1_2_0
-	LilvNodes *required_features = lilv_plugin_get_required_features (plugin);
-	if (lilv_nodes_contains (required_features, _world.bufz_powerOf2BlockLength) ||
-			lilv_nodes_contains (required_features, _world.bufz_fixedBlockLength)
-	   ) {
-		error << string_compose(
-		    _("LV2: \"%1\" buffer-size requirements cannot be satisfied."),
-		    lilv_node_as_string(_impl->name)) << endmsg;
-		lilv_node_free(_impl->name);
-		lilv_node_free(_impl->author);
-		lilv_nodes_free(required_features);
-		throw failed_constructor();
-	}
-	lilv_nodes_free(required_features);
-#endif
-
 	LilvNodes* optional_features = lilv_plugin_get_optional_features (plugin);
 #ifdef HAVE_LV2_1_2_0
 	if (lilv_nodes_contains (optional_features, _world.bufz_coarseBlockLength)) {
@@ -3258,6 +3244,7 @@ LV2World::LV2World()
 	units_db           = lilv_new_uri(world, LV2_UNITS__db);
 	patch_writable     = lilv_new_uri(world, LV2_PATCH__writable);
 	patch_Message      = lilv_new_uri(world, LV2_PATCH__Message);
+	opts_requiredOptions = lilv_new_uri(world, LV2_OPTIONS__requiredOption);
 #ifdef LV2_EXTENDED
 	lv2_noSampleAccurateCtrl    = lilv_new_uri(world, "http://ardour.org/lv2/ext#noSampleAccurateControls"); // deprecated 2016-09-18
 	auto_can_write_automatation = lilv_new_uri(world, LV2_AUTOMATE_URI__can_write);
@@ -3294,6 +3281,7 @@ LV2World::~LV2World()
 	lilv_node_free(auto_automation_controller);
 #endif
 	lilv_node_free(patch_Message);
+	lilv_node_free(opts_requiredOptions);
 	lilv_node_free(patch_writable);
 	lilv_node_free(units_hz);
 	lilv_node_free(units_midiNote);
@@ -3485,18 +3473,56 @@ LV2PluginInfo::discover()
 		}
 
 #ifdef HAVE_LV2_1_2_0
-		LilvNodes *required_features = lilv_plugin_get_required_features (p);
-		if (lilv_nodes_contains (required_features, world.bufz_powerOf2BlockLength) ||
-				lilv_nodes_contains (required_features, world.bufz_fixedBlockLength)
-		   ) {
-			warning << string_compose(
-			    _("Ignoring LV2 plugin \"%1\" because its buffer-size requirements cannot be satisfied."),
-			    lilv_node_as_string(name)) << endmsg;
-			lilv_nodes_free(required_features);
-			lilv_node_free(name);
+		int err = 0;
+		LilvNodes* required_features = lilv_plugin_get_required_features (p);
+		LILV_FOREACH(nodes, i, required_features) {
+				const char* rf = lilv_node_as_uri (lilv_nodes_get (required_features, i));
+				bool ok = false;
+				if (!strcmp (rf, "http://lv2plug.in/ns/ext/instance-access")) { ok = true; }
+				if (!strcmp (rf, "http://lv2plug.in/ns/ext/data-access")) { ok = true; }
+				if (!strcmp (rf, LV2_STATE__makePath)) { ok = true; }
+				if (!strcmp (rf, LV2_LOG__log)) { ok = true; }
+				if (!strcmp (rf, LV2_WORKER__schedule)) { ok = true; }
+				if (!strcmp (rf, LV2_STATE_PREFIX "loadDefaultState")) { ok = true; }
+				if (!strcmp (rf, LV2_URID_MAP_URI)) { ok = true; }
+				if (!strcmp (rf, LV2_URID_UNMAP_URI)) { ok = true; }
+				if (!strcmp (rf, "http://lv2plug.in/ns/lv2core#isLive")) { ok = true; }
+				if (!ok) {
+					warning << string_compose (
+							_("Unsupported required LV2 feature: '%1' in '%2'."),
+							rf, lilv_node_as_string(name)) << endmsg;
+					err = 1;
+				}
+		}
+
+		if (err) {
+			continue;
+		}
+
+		lilv_nodes_free (required_features);
+
+		LilvNodes* required_options = lilv_world_find_nodes (world.world, lilv_plugin_get_uri (p), world.opts_requiredOptions, NULL);
+		if (required_options) {
+			LILV_FOREACH(nodes, i, required_options) {
+				const char* ro = lilv_node_as_uri (lilv_nodes_get (required_options, i));
+				bool ok = false;
+				if (!strcmp (ro, LV2_PARAMETERS__sampleRate)) { ok = true; }
+				if (!strcmp (ro, LV2_BUF_SIZE__minBlockLength)) { ok = true; }
+				if (!strcmp (ro, LV2_BUF_SIZE__maxBlockLength)) { ok = true; }
+				if (!strcmp (ro, LV2_BUF_SIZE__sequenceSize)) { ok = true; }
+				if (!ok) {
+					warning << string_compose (
+							_("Unsupported required LV2 option: '%1' in '%2'."),
+							ro, lilv_node_as_string(name)) << endmsg;
+					err = 1;
+				}
+			}
+		}
+		lilv_nodes_free(required_options);
+
+		if (err) {
 			continue;
 		}
-		lilv_nodes_free(required_features);
 #endif
 
 		info->type = LV2;