possible fix for race between diskstream buffer overwrite and channel setup
[ardour2.git] / libs / ardour / lv2_plugin.cc
blob368c521d0b9a093f9e4d39593e7e9db96305a067
1 /*
2 Copyright (C) 2008 Paul Davis
3 Author: Dave Robillard
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #include <vector>
22 #include <string>
24 #include <cstdlib>
25 #include <cmath>
26 #include <cstring>
28 #include "pbd/compose.h"
29 #include "pbd/error.h"
30 #include "pbd/pathscanner.h"
31 #include "pbd/xml++.h"
33 #include "ardour/ardour.h"
34 #include "ardour/session.h"
35 #include "ardour/audioengine.h"
36 #include "ardour/audio_buffer.h"
37 #include "ardour/lv2_event_buffer.h"
38 #include "ardour/lv2_plugin.h"
40 #include "pbd/stl_delete.h"
42 #include "i18n.h"
43 #include <locale.h>
45 using namespace std;
46 using namespace ARDOUR;
47 using namespace PBD;
49 URIMap LV2Plugin::_uri_map;
50 uint32_t LV2Plugin::_midi_event_type = _uri_map.uri_to_id(
51 "http://lv2plug.in/ns/ext/event",
52 "http://lv2plug.in/ns/ext/midi#MidiEvent");
54 LV2Plugin::LV2Plugin (AudioEngine& e, Session& session, LV2World& world, SLV2Plugin plugin, nframes_t rate)
55 : Plugin (e, session)
56 , _world(world)
57 , _features(NULL)
59 init (world, plugin, rate);
62 LV2Plugin::LV2Plugin (const LV2Plugin &other)
63 : Plugin (other)
64 , _world(other._world)
65 , _features(NULL)
67 init (other._world, other._plugin, other._sample_rate);
69 for (uint32_t i = 0; i < parameter_count(); ++i) {
70 _control_data[i] = other._shadow_data[i];
71 _shadow_data[i] = other._shadow_data[i];
75 void
76 LV2Plugin::init (LV2World& world, SLV2Plugin plugin, nframes_t rate)
78 _world = world;
79 _plugin = plugin;
80 _ui = NULL;
81 _control_data = 0;
82 _shadow_data = 0;
83 _latency_control_port = 0;
84 _was_activated = false;
86 _instance = slv2_plugin_instantiate(plugin, rate, _features);
87 _name = slv2_plugin_get_name(plugin);
88 assert(_name);
89 _author = slv2_plugin_get_author_name(plugin);
91 if (_instance == 0) {
92 error << _("LV2: Failed to instantiate plugin ") << slv2_plugin_get_uri(plugin) << endl;
93 throw failed_constructor();
96 if (slv2_plugin_has_feature(plugin, world.in_place_broken)) {
97 error << string_compose(
98 _("LV2: \"%1\" cannot be used, since it cannot do inplace processing"),
99 slv2_value_as_string(_name));
100 slv2_value_free(_name);
101 slv2_value_free(_author);
102 throw failed_constructor();
105 _instance_access_feature.URI = "http://lv2plug.in/ns/ext/instance-access";
106 _instance_access_feature.data = (void*)_instance->lv2_handle;
108 _data_access_extension_data.extension_data = _instance->lv2_descriptor->extension_data;
109 _data_access_feature.URI = "http://lv2plug.in/ns/ext/data-access";
110 _data_access_feature.data = &_data_access_extension_data;
112 _features = (LV2_Feature**)malloc(sizeof(LV2_Feature*) * 4);
113 _features[0] = &_instance_access_feature;
114 _features[1] = &_data_access_feature;
115 _features[2] = _uri_map.feature();
116 _features[3] = NULL;
118 _sample_rate = rate;
120 const uint32_t num_ports = slv2_plugin_get_num_ports(plugin);
122 _control_data = new float[num_ports];
123 _shadow_data = new float[num_ports];
124 _defaults = new float[num_ports];
126 const bool latent = slv2_plugin_has_latency(plugin);
127 uint32_t latency_port = (latent ? slv2_plugin_get_latency_port_index(plugin) : 0);
129 for (uint32_t i = 0; i < num_ports; ++i) {
130 SLV2Port port = slv2_plugin_get_port_by_index(plugin, i);
131 SLV2Value sym = slv2_port_get_symbol(_plugin, port);
132 _port_indices.insert(std::make_pair(slv2_value_as_string(sym), i));
133 if (parameter_is_control(i)) {
134 SLV2Value def;
135 slv2_port_get_range(plugin, port, &def, NULL, NULL);
136 _defaults[i] = def ? slv2_value_as_float(def) : 0.0f;
137 slv2_value_free(def);
139 slv2_instance_connect_port (_instance, i, &_control_data[i]);
141 if (latent && i == latency_port) {
142 _latency_control_port = &_control_data[i];
143 *_latency_control_port = 0;
146 if (parameter_is_input(i)) {
147 _shadow_data[i] = default_value (i);
149 } else {
150 _defaults[i] = 0.0f;
154 SLV2UIs uis = slv2_plugin_get_uis(_plugin);
155 if (slv2_uis_size(uis) > 0) {
156 for (unsigned i=0; i < slv2_uis_size(uis); ++i) {
157 SLV2UI ui = slv2_uis_get_at(uis, i);
158 if (slv2_ui_is_a(ui, _world.gtk_gui)) {
159 _ui = ui;
160 break;
164 // if gtk gui is not available, try to find external gui
165 if (!_ui) {
166 for (unsigned i=0; i < slv2_uis_size(uis); ++i) {
167 SLV2UI ui = slv2_uis_get_at(uis, i);
168 if (slv2_ui_is_a(ui, _world.external_gui)) {
169 _ui = ui;
170 break;
176 latency_compute_run ();
179 LV2Plugin::~LV2Plugin ()
181 deactivate ();
182 cleanup ();
184 slv2_instance_free(_instance);
185 slv2_value_free(_name);
186 slv2_value_free(_author);
188 delete [] _control_data;
189 delete [] _shadow_data;
192 bool
193 LV2Plugin::is_external_ui() const
195 return slv2_ui_is_a(_ui, _world.external_gui);
198 string
199 LV2Plugin::unique_id() const
201 return slv2_value_as_uri(slv2_plugin_get_uri(_plugin));
205 float
206 LV2Plugin::default_value (uint32_t port)
208 return _defaults[port];
211 const char*
212 LV2Plugin::port_symbol (uint32_t index)
214 SLV2Port port = slv2_plugin_get_port_by_index(_plugin, index);
215 if (!port) {
216 error << name() << ": Invalid port index " << index << endmsg;
219 SLV2Value sym = slv2_port_get_symbol(_plugin, port);
220 return slv2_value_as_string(sym);
224 void
225 LV2Plugin::set_parameter (uint32_t which, float val)
227 if (which < slv2_plugin_get_num_ports(_plugin)) {
228 _shadow_data[which] = val;
229 #if 0
230 ParameterChanged (which, val); /* EMIT SIGNAL */
232 if (which < parameter_count() && controls[which]) {
233 controls[which]->Changed ();
235 #endif
237 } else {
238 warning << string_compose (_("Illegal parameter number used with plugin \"%1\"."
239 "This is a bug in either %2 or the LV2 plugin (%3)"),
240 name(), PROGRAM_NAME, unique_id()) << endmsg;
244 float
245 LV2Plugin::get_parameter (uint32_t which) const
247 if (parameter_is_input(which)) {
248 return (float) _shadow_data[which];
249 } else {
250 return (float) _control_data[which];
252 return 0.0f;
255 uint32_t
256 LV2Plugin::nth_parameter (uint32_t n, bool& ok) const
258 uint32_t x, c;
260 ok = false;
262 for (c = 0, x = 0; x < slv2_plugin_get_num_ports(_plugin); ++x) {
263 if (parameter_is_control (x)) {
264 if (c++ == n) {
265 ok = true;
266 return x;
271 return 0;
274 XMLNode&
275 LV2Plugin::get_state()
277 XMLNode *root = new XMLNode(state_node_name());
278 XMLNode *child;
279 char buf[16];
280 LocaleGuard lg (X_("POSIX"));
282 for (uint32_t i = 0; i < parameter_count(); ++i){
284 if (parameter_is_input(i) && parameter_is_control(i)) {
285 child = new XMLNode("Port");
286 /*snprintf(buf, sizeof(buf), "%u", i);
287 child->add_property("number", string(buf));*/
288 child->add_property("symbol", port_symbol(i));
289 snprintf(buf, sizeof(buf), "%+f", _shadow_data[i]);
290 child->add_property("value", string(buf));
291 root->add_child_nocopy (*child);
293 /*if (i < controls.size() && controls[i]) {
294 root->add_child_nocopy (controls[i]->get_state());
299 return *root;
302 vector<Plugin::PresetRecord>
303 LV2Plugin::get_presets()
305 vector<PresetRecord> result;
306 SLV2Results presets = slv2_plugin_query_sparql(_plugin,
307 "PREFIX lv2p: <http://lv2plug.in/ns/dev/presets#>\n"
308 "PREFIX dc: <http://dublincore.org/documents/dcmi-namespace/>\n"
309 "SELECT ?p ?name WHERE { <> lv2p:hasPreset ?p . ?p dc:title ?name }\n");
310 for (; !slv2_results_finished(presets); slv2_results_next(presets)) {
311 SLV2Value uri = slv2_results_get_binding_value(presets, 0);
312 SLV2Value name = slv2_results_get_binding_value(presets, 1);
313 PresetRecord rec(slv2_value_as_string(uri), slv2_value_as_string(name));
314 result.push_back(rec);
315 this->presets.insert(std::make_pair(slv2_value_as_string(uri), rec));
317 slv2_results_free(presets);
318 return result;
321 bool
322 LV2Plugin::load_preset(const string& uri)
324 const string query = string(
325 "PREFIX lv2p: <http://lv2plug.in/ns/dev/presets#>\n"
326 "PREFIX dc: <http://dublincore.org/documents/dcmi-namespace/>\n"
327 "SELECT ?sym ?val WHERE { <") + uri + "> lv2:port ?port . "
328 " ?port lv2:symbol ?sym ; lv2p:value ?val . }";
329 SLV2Results values = slv2_plugin_query_sparql(_plugin, query.c_str());
330 for (; !slv2_results_finished(values); slv2_results_next(values)) {
331 SLV2Value sym = slv2_results_get_binding_value(values, 0);
332 SLV2Value val = slv2_results_get_binding_value(values, 1);
333 if (slv2_value_is_float(val)) {
334 uint32_t index = _port_indices[slv2_value_as_string(sym)];
335 set_parameter(index, slv2_value_as_float(val));
338 slv2_results_free(values);
339 return true;
342 bool
343 LV2Plugin::save_preset (string /*name*/)
345 return false;
348 bool
349 LV2Plugin::has_editor() const
351 return (_ui != NULL);
355 LV2Plugin::set_state(const XMLNode& node, int version)
357 XMLNodeList nodes;
358 XMLProperty *prop;
359 XMLNodeConstIterator iter;
360 XMLNode *child;
361 const char *sym;
362 const char *value;
363 uint32_t port_id;
364 LocaleGuard lg (X_("POSIX"));
366 if (node.name() != state_node_name()) {
367 error << _("Bad node sent to LV2Plugin::set_state") << endmsg;
368 return -1;
371 if (version < 3000){
372 nodes = node.children ("port");
373 } else {
374 nodes = node.children ("Port");
377 for (iter = nodes.begin(); iter != nodes.end(); ++iter){
379 child = *iter;
381 if ((prop = child->property("symbol")) != 0) {
382 sym = prop->value().c_str();
383 } else {
384 warning << _("LV2: port has no symbol, ignored") << endmsg;
385 continue;
388 map<string,uint32_t>::iterator i = _port_indices.find(sym);
390 if (i != _port_indices.end()) {
391 port_id = i->second;
392 } else {
393 warning << _("LV2: port has unknown index, ignored") << endmsg;
394 continue;
397 if ((prop = child->property("value")) != 0) {
398 value = prop->value().c_str();
399 } else {
400 warning << _("LV2: port has no value, ignored") << endmsg;
401 continue;
404 set_parameter (port_id, atof(value));
407 latency_compute_run ();
409 return 0;
413 LV2Plugin::get_parameter_descriptor (uint32_t which, ParameterDescriptor& desc) const
415 SLV2Port port = slv2_plugin_get_port_by_index(_plugin, which);
417 SLV2Value def, min, max;
418 slv2_port_get_range(_plugin, port, &def, &min, &max);
420 desc.integer_step = slv2_port_has_property(_plugin, port, _world.integer);
421 desc.toggled = slv2_port_has_property(_plugin, port, _world.toggled);
422 desc.logarithmic = slv2_port_has_property(_plugin, port, _world.logarithmic);
423 desc.sr_dependent = slv2_port_has_property(_plugin, port, _world.srate);
424 desc.label = slv2_value_as_string(slv2_port_get_name(_plugin, port));
425 desc.lower = min ? slv2_value_as_float(min) : 0.0f;
426 desc.upper = max ? slv2_value_as_float(max) : 1.0f;
427 desc.min_unbound = false; // TODO (LV2 extension)
428 desc.max_unbound = false; // TODO (LV2 extension)
430 if (desc.integer_step) {
431 desc.step = 1.0;
432 desc.smallstep = 0.1;
433 desc.largestep = 10.0;
434 } else {
435 const float delta = desc.upper - desc.lower;
436 desc.step = delta / 1000.0f;
437 desc.smallstep = delta / 10000.0f;
438 desc.largestep = delta/10.0f;
441 slv2_value_free(def);
442 slv2_value_free(min);
443 slv2_value_free(max);
445 return 0;
449 string
450 LV2Plugin::describe_parameter (Evoral::Parameter which)
452 if (which.type() == PluginAutomation && which.id() < parameter_count()) {
453 SLV2Value name = slv2_port_get_name(_plugin,
454 slv2_plugin_get_port_by_index(_plugin, which));
455 string ret(slv2_value_as_string(name));
456 slv2_value_free(name);
457 return ret;
458 } else {
459 return "??";
463 nframes_t
464 LV2Plugin::signal_latency () const
466 if (_latency_control_port) {
467 return (nframes_t) floor (*_latency_control_port);
468 } else {
469 return 0;
473 set<Evoral::Parameter>
474 LV2Plugin::automatable () const
476 set<Evoral::Parameter> ret;
478 for (uint32_t i = 0; i < parameter_count(); ++i){
479 if (parameter_is_input(i) && parameter_is_control(i)) {
480 ret.insert (ret.end(), Evoral::Parameter(PluginAutomation, 0, i));
484 return ret;
488 LV2Plugin::connect_and_run (BufferSet& bufs,
489 ChanMapping in_map, ChanMapping out_map,
490 nframes_t nframes, nframes_t offset)
492 cycles_t then = get_cycles ();
494 uint32_t audio_in_index = 0;
495 uint32_t audio_out_index = 0;
496 uint32_t midi_in_index = 0;
497 uint32_t midi_out_index = 0;
498 for (uint32_t port_index = 0; port_index < parameter_count(); ++port_index) {
499 if (parameter_is_audio(port_index)) {
500 if (parameter_is_input(port_index)) {
501 const uint32_t buf_index = in_map.get(DataType::AUDIO, audio_in_index++);
502 //cerr << port_index << " : " << " AUDIO IN " << buf_index << endl;
503 slv2_instance_connect_port(_instance, port_index,
504 bufs.get_audio(buf_index).data(offset));
505 } else if (parameter_is_output(port_index)) {
506 const uint32_t buf_index = out_map.get(DataType::AUDIO, audio_out_index++);
507 //cerr << port_index << " : " << " AUDIO OUT " << buf_index << endl;
508 slv2_instance_connect_port(_instance, port_index,
509 bufs.get_audio(buf_index).data(offset));
511 } else if (parameter_is_midi(port_index)) {
512 if (parameter_is_input(port_index)) {
513 const uint32_t buf_index = in_map.get(DataType::MIDI, midi_in_index++);
514 //cerr << port_index << " : " << " MIDI IN " << buf_index << endl;
515 slv2_instance_connect_port(_instance, port_index,
516 bufs.get_lv2_midi(true, buf_index).data());
517 } else if (parameter_is_output(port_index)) {
518 const uint32_t buf_index = out_map.get(DataType::MIDI, midi_out_index++);
519 //cerr << port_index << " : " << " MIDI OUT " << buf_index << endl;
520 slv2_instance_connect_port(_instance, port_index,
521 bufs.get_lv2_midi(false, buf_index).data());
523 } else if (!parameter_is_control(port_index)) {
524 // Optional port (it'd better be if we've made it this far...)
525 slv2_instance_connect_port(_instance, port_index, NULL);
529 run (nframes);
531 midi_out_index = 0;
532 for (uint32_t port_index = 0; port_index < parameter_count(); ++port_index) {
533 if (parameter_is_midi(port_index) && parameter_is_output(port_index)) {
534 const uint32_t buf_index = out_map.get(DataType::MIDI, midi_out_index++);
535 bufs.flush_lv2_midi(true, buf_index);
539 cycles_t now = get_cycles ();
540 set_cycles ((uint32_t) (now - then));
542 return 0;
545 bool
546 LV2Plugin::parameter_is_control (uint32_t param) const
548 SLV2Port port = slv2_plugin_get_port_by_index(_plugin, param);
549 return slv2_port_is_a(_plugin, port, _world.control_class);
552 bool
553 LV2Plugin::parameter_is_audio (uint32_t param) const
555 SLV2Port port = slv2_plugin_get_port_by_index(_plugin, param);
556 return slv2_port_is_a(_plugin, port, _world.audio_class);
559 bool
560 LV2Plugin::parameter_is_midi (uint32_t param) const
562 SLV2Port port = slv2_plugin_get_port_by_index(_plugin, param);
563 return slv2_port_is_a(_plugin, port, _world.event_class);
564 // && slv2_port_supports_event(_plugin, port, _world.midi_class);
567 bool
568 LV2Plugin::parameter_is_output (uint32_t param) const
570 SLV2Port port = slv2_plugin_get_port_by_index(_plugin, param);
571 return slv2_port_is_a(_plugin, port, _world.output_class);
574 bool
575 LV2Plugin::parameter_is_input (uint32_t param) const
577 SLV2Port port = slv2_plugin_get_port_by_index(_plugin, param);
578 return slv2_port_is_a(_plugin, port, _world.input_class);
581 void
582 LV2Plugin::print_parameter (uint32_t param, char *buf, uint32_t len) const
584 if (buf && len) {
585 if (param < parameter_count()) {
586 snprintf (buf, len, "%.3f", get_parameter (param));
587 } else {
588 strcat (buf, "0");
593 void
594 LV2Plugin::run (nframes_t nframes)
596 for (uint32_t i = 0; i < parameter_count(); ++i) {
597 if (parameter_is_control(i) && parameter_is_input(i)) {
598 _control_data[i] = _shadow_data[i];
602 slv2_instance_run(_instance, nframes);
605 void
606 LV2Plugin::latency_compute_run ()
608 if (!_latency_control_port) {
609 return;
612 /* we need to run the plugin so that it can set its latency
613 parameter.
616 activate ();
618 uint32_t port_index = 0;
619 uint32_t in_index = 0;
620 uint32_t out_index = 0;
621 const nframes_t bufsize = 1024;
622 float buffer[bufsize];
624 memset(buffer,0,sizeof(float)*bufsize);
626 /* Note that we've already required that plugins
627 be able to handle in-place processing.
630 port_index = 0;
632 while (port_index < parameter_count()) {
633 if (parameter_is_audio (port_index)) {
634 if (parameter_is_input (port_index)) {
635 slv2_instance_connect_port (_instance, port_index, buffer);
636 in_index++;
637 } else if (parameter_is_output (port_index)) {
638 slv2_instance_connect_port (_instance, port_index, buffer);
639 out_index++;
642 port_index++;
645 run (bufsize);
646 deactivate ();
649 LV2World::LV2World()
650 : world(slv2_world_new())
652 slv2_world_load_all(world);
653 input_class = slv2_value_new_uri(world, SLV2_PORT_CLASS_INPUT);
654 output_class = slv2_value_new_uri(world, SLV2_PORT_CLASS_OUTPUT);
655 control_class = slv2_value_new_uri(world, SLV2_PORT_CLASS_CONTROL);
656 audio_class = slv2_value_new_uri(world, SLV2_PORT_CLASS_AUDIO);
657 event_class = slv2_value_new_uri(world, SLV2_PORT_CLASS_EVENT);
658 midi_class = slv2_value_new_uri(world, SLV2_EVENT_CLASS_MIDI);
659 in_place_broken = slv2_value_new_uri(world, SLV2_NAMESPACE_LV2 "inPlaceBroken");
660 integer = slv2_value_new_uri(world, SLV2_NAMESPACE_LV2 "integer");
661 toggled = slv2_value_new_uri(world, SLV2_NAMESPACE_LV2 "toggled");
662 srate = slv2_value_new_uri(world, SLV2_NAMESPACE_LV2 "sampleRate");
663 gtk_gui = slv2_value_new_uri(world, "http://lv2plug.in/ns/extensions/ui#GtkUI");
664 external_gui = slv2_value_new_uri(world, "http://lv2plug.in/ns/extensions/ui#external");
665 logarithmic = slv2_value_new_uri(world, "http://lv2plug.in/ns/dev/extportinfo#logarithmic");
668 LV2World::~LV2World()
670 slv2_value_free(input_class);
671 slv2_value_free(output_class);
672 slv2_value_free(control_class);
673 slv2_value_free(audio_class);
674 slv2_value_free(event_class);
675 slv2_value_free(midi_class);
676 slv2_value_free(in_place_broken);
679 LV2PluginInfo::LV2PluginInfo (void* lv2_world, void* slv2_plugin)
680 : _lv2_world(lv2_world)
681 , _slv2_plugin(slv2_plugin)
685 LV2PluginInfo::~LV2PluginInfo()
689 PluginPtr
690 LV2PluginInfo::load (Session& session)
692 try {
693 PluginPtr plugin;
695 plugin.reset (new LV2Plugin (session.engine(), session,
696 *(LV2World*)_lv2_world, (SLV2Plugin)_slv2_plugin, session.frame_rate()));
698 plugin->set_info(PluginInfoPtr(new LV2PluginInfo(*this)));
699 return plugin;
702 catch (failed_constructor &err) {
703 return PluginPtr ((Plugin*) 0);
706 return PluginPtr();
709 PluginInfoList*
710 LV2PluginInfo::discover (void* lv2_world)
712 PluginInfoList* plugs = new PluginInfoList;
714 LV2World* world = (LV2World*)lv2_world;
715 SLV2Plugins plugins = slv2_world_get_all_plugins(world->world);
717 cerr << "LV2: Discovering " << slv2_plugins_size (plugins) << " plugins" << endl;
719 for (unsigned i=0; i < slv2_plugins_size(plugins); ++i) {
720 SLV2Plugin p = slv2_plugins_get_at(plugins, i);
721 LV2PluginInfoPtr info (new LV2PluginInfo(lv2_world, p));
723 SLV2Value name = slv2_plugin_get_name(p);
725 if (!name) {
726 cerr << "LV2: invalid plugin\n";
727 continue;
730 info->type = LV2;
732 info->name = string(slv2_value_as_string(name));
733 slv2_value_free(name);
735 SLV2PluginClass pclass = slv2_plugin_get_class(p);
736 SLV2Value label = slv2_plugin_class_get_label(pclass);
737 info->category = slv2_value_as_string(label);
739 SLV2Value author_name = slv2_plugin_get_author_name(p);
740 info->creator = author_name ? string(slv2_value_as_string(author_name)) : "Unknown";
741 slv2_value_free(author_name);
743 info->path = "/NOPATH"; // Meaningless for LV2
745 info->n_inputs.set_audio(slv2_plugin_get_num_ports_of_class(p,
746 world->input_class, world->audio_class, NULL));
747 info->n_inputs.set_midi(slv2_plugin_get_num_ports_of_class(p,
748 world->input_class, world->event_class, NULL));
750 info->n_outputs.set_audio(slv2_plugin_get_num_ports_of_class(p,
751 world->output_class, world->audio_class, NULL));
752 info->n_outputs.set_midi(slv2_plugin_get_num_ports_of_class(p,
753 world->output_class, world->event_class, NULL));
755 info->unique_id = slv2_value_as_uri(slv2_plugin_get_uri(p));
756 info->index = 0; // Meaningless for LV2
758 plugs->push_back (info);
761 cerr << "Done LV2 discovery" << endl;
763 return plugs;