ladspa_plugin.cc

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/*
    Copyright (C) 2000-2006 Paul Davis

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#ifdef WAF_BUILD
#include "libardour-config.h"
#endif

#include <inttypes.h>

#include <vector>
#include <string>

#include <cstdlib>
#include <cstdio> // so libraptor doesn't complain
#include <cmath>
#ifndef COMPILER_MSVC
#include <dirent.h>
#endif
#include <sys/stat.h>
#include <cerrno>

#ifdef HAVE_LRDF
#include <lrdf.h>
#endif

#include "pbd/compose.h"
#include "pbd/error.h"
#include "pbd/xml++.h"
#include "pbd/stacktrace.h"

#include "ardour/session.h"
#include "ardour/ladspa_plugin.h"
#include "ardour/buffer_set.h"
#include "ardour/audio_buffer.h"

#include "pbd/stl_delete.h"

#include "i18n.h"
#include <locale.h>

using namespace std;
using namespace ARDOUR;
using namespace PBD;

LadspaPlugin::LadspaPlugin (string module_path, AudioEngine& e, Session& session, uint32_t index, framecnt_t rate)
        : Plugin (e, session)
{
        init (module_path, index, rate);
}

LadspaPlugin::LadspaPlugin (const LadspaPlugin &other)
        : Plugin (other)
{
        init (other._module_path, other._index, other._sample_rate);

        for (uint32_t i = 0; i < parameter_count(); ++i) {
                _control_data[i] = other._shadow_data[i];
                _shadow_data[i] = other._shadow_data[i];
        }
}

void
LadspaPlugin::init (string module_path, uint32_t index, framecnt_t rate)
{
        void* func;
        LADSPA_Descriptor_Function dfunc;
        uint32_t i, port_cnt;

        _module_path = module_path;
        _module = new Glib::Module(_module_path);
        _control_data = 0;
        _shadow_data = 0;
        _latency_control_port = 0;
        _was_activated = false;

        if (!(*_module)) {
                error << _("LADSPA: Unable to open module: ") << Glib::Module::get_last_error() << endmsg;
                delete _module;
                throw failed_constructor();
        }

        if (!_module->get_symbol("ladspa_descriptor", func)) {
                error << _("LADSPA: module has no descriptor function.") << endmsg;
                throw failed_constructor();
        }

        dfunc = (LADSPA_Descriptor_Function)func;

        if ((_descriptor = dfunc (index)) == 0) {
                error << _("LADSPA: plugin has gone away since discovery!") << endmsg;
                throw failed_constructor();
        }

        _index = index;

        if (LADSPA_IS_INPLACE_BROKEN(_descriptor->Properties)) {
                error << string_compose(_("LADSPA: \"%1\" cannot be used, since it cannot do inplace processing"), _descriptor->Name) << endmsg;
                throw failed_constructor();
        }

        _sample_rate = rate;

        if (_descriptor->instantiate == 0) {
                throw failed_constructor();
        }

        if ((_handle = _descriptor->instantiate (_descriptor, rate)) == 0) {
                throw failed_constructor();
        }

        port_cnt = parameter_count();

        _control_data = new LADSPA_Data[port_cnt];
        memset (_control_data, 0, sizeof (LADSPA_Data) * port_cnt);
        _shadow_data = new LADSPA_Data[port_cnt];
        memset (_shadow_data, 0, sizeof (LADSPA_Data) * port_cnt);

        for (i = 0; i < port_cnt; ++i) {
                if (LADSPA_IS_PORT_CONTROL(port_descriptor (i))) {
                        connect_port (i, &_control_data[i]);

                        if (LADSPA_IS_PORT_OUTPUT(port_descriptor (i)) &&
                            strcmp (port_names()[i], X_("latency")) == 0) {
                                _latency_control_port = &_control_data[i];
                                *_latency_control_port = 0;
                        }

                        if (!LADSPA_IS_PORT_INPUT(port_descriptor (i))) {
                                continue;
                        }

                        _shadow_data[i] = _default_value (i);
                }
        }

        latency_compute_run ();
}

LadspaPlugin::~LadspaPlugin ()
{
        deactivate ();
        cleanup ();

        // glib has internal reference counting on modules so this is ok
        delete _module;

        delete [] _control_data;
        delete [] _shadow_data;
}

string
LadspaPlugin::unique_id() const
{
        char buf[32];
        snprintf (buf, sizeof (buf), "%lu", _descriptor->UniqueID);
        return string (buf);
}

float
LadspaPlugin::_default_value (uint32_t port) const
{
        const LADSPA_PortRangeHint *prh = port_range_hints();
        float ret = 0.0f;
        bool bounds_given = false;
        bool sr_scaling = false;
        bool earlier_hint = false;

        /* defaults - case 1 */

        if (LADSPA_IS_HINT_HAS_DEFAULT(prh[port].HintDescriptor)) {
                if (LADSPA_IS_HINT_DEFAULT_MINIMUM(prh[port].HintDescriptor)) {
                        ret = prh[port].LowerBound;
                        bounds_given = true;
                        sr_scaling = true;
                }

                else if (LADSPA_IS_HINT_DEFAULT_LOW(prh[port].HintDescriptor)) {
                        ret = prh[port].LowerBound * 0.75f + prh[port].UpperBound * 0.25f;
                        bounds_given = true;
                        sr_scaling = true;
                }
                else if (LADSPA_IS_HINT_DEFAULT_MIDDLE(prh[port].HintDescriptor)) {
                        ret = prh[port].LowerBound * 0.5f + prh[port].UpperBound * 0.5f;
                        bounds_given = true;
                        sr_scaling = true;
                }
                else if (LADSPA_IS_HINT_DEFAULT_HIGH(prh[port].HintDescriptor)) {
                        ret = prh[port].LowerBound * 0.25f + prh[port].UpperBound * 0.75f;
                        bounds_given = true;
                        sr_scaling = true;
                }
                else if (LADSPA_IS_HINT_DEFAULT_MAXIMUM(prh[port].HintDescriptor)) {
                        ret = prh[port].UpperBound;
                        bounds_given = true;
                        sr_scaling = true;
                }
                else if (LADSPA_IS_HINT_DEFAULT_0(prh[port].HintDescriptor)) {
                        ret = 0.0f;
                        earlier_hint = true;
                }
                else if (LADSPA_IS_HINT_DEFAULT_1(prh[port].HintDescriptor)) {
                        ret = 1.0f;
                        earlier_hint = true;
                }
                else if (LADSPA_IS_HINT_DEFAULT_100(prh[port].HintDescriptor)) {
                        ret = 100.0f;
                        earlier_hint = true;
                }
                else if (LADSPA_IS_HINT_DEFAULT_440(prh[port].HintDescriptor)) {
                        ret = 440.0f;
                        earlier_hint = true;
                }
                else {
                        /* no hint found */
                        ret = 0.0f;
                }
        }

        /* defaults - case 2 */
        else if (LADSPA_IS_HINT_BOUNDED_BELOW(prh[port].HintDescriptor) &&
                 !LADSPA_IS_HINT_BOUNDED_ABOVE(prh[port].HintDescriptor)) {

                if (prh[port].LowerBound < 0) {
                        ret = 0.0f;
                } else {
                        ret = prh[port].LowerBound;
                }

                bounds_given = true;
                sr_scaling = true;
        }

        /* defaults - case 3 */
        else if (!LADSPA_IS_HINT_BOUNDED_BELOW(prh[port].HintDescriptor) &&
                 LADSPA_IS_HINT_BOUNDED_ABOVE(prh[port].HintDescriptor)) {

                if (prh[port].UpperBound > 0) {
                        ret = 0.0f;
                } else {
                        ret = prh[port].UpperBound;
                }

                bounds_given = true;
                sr_scaling = true;
        }

        /* defaults - case 4 */
        else if (LADSPA_IS_HINT_BOUNDED_BELOW(prh[port].HintDescriptor) &&
                 LADSPA_IS_HINT_BOUNDED_ABOVE(prh[port].HintDescriptor)) {

                if (prh[port].LowerBound < 0 && prh[port].UpperBound > 0) {
                        ret = 0.0f;
                } else if (prh[port].LowerBound < 0 && prh[port].UpperBound < 0) {
                        ret = prh[port].UpperBound;
                } else {
                        ret = prh[port].LowerBound;
                }
                bounds_given = true;
                sr_scaling = true;
        }

        /* defaults - case 5 */

        if (LADSPA_IS_HINT_SAMPLE_RATE(prh[port].HintDescriptor) && !earlier_hint) {
                if (bounds_given) {
                        if (sr_scaling) {
                                ret *= _sample_rate;
                        }
                } else {
                        ret = _sample_rate;
                }
        }

        return ret;
}

void
LadspaPlugin::set_parameter (uint32_t which, float val)
{
        if (which < _descriptor->PortCount) {

                if (get_parameter (which) == val) {
                        return;
                }

                _shadow_data[which] = (LADSPA_Data) val;

#if 0
                if (which < parameter_count() && controls[which]) {
                        controls[which]->Changed ();
                }
#endif

        } else {
                warning << string_compose (_("illegal parameter number used with plugin \"%1\". This may "
                                             "indicate a change in the plugin design, and presets may be "
                                             "invalid"), name())
                        << endmsg;
        }

        Plugin::set_parameter (which, val);
}

float
LadspaPlugin::get_parameter (uint32_t which) const
{
        if (LADSPA_IS_PORT_INPUT(port_descriptor (which))) {
                return (float) _shadow_data[which];
        } else {
                return (float) _control_data[which];
        }
}

uint32_t
LadspaPlugin::nth_parameter (uint32_t n, bool& ok) const
{
        uint32_t x, c;

        ok = false;

        for (c = 0, x = 0; x < _descriptor->PortCount; ++x) {
                if (LADSPA_IS_PORT_CONTROL (port_descriptor (x))) {
                        if (c++ == n) {
                                ok = true;
                                return x;
                        }
                }
        }
        return 0;
}

void
LadspaPlugin::add_state (XMLNode* root) const
{
        XMLNode *child;
        char buf[16];
        LocaleGuard lg (X_("C"));

        for (uint32_t i = 0; i < parameter_count(); ++i){

                if (LADSPA_IS_PORT_INPUT(port_descriptor (i)) &&
                    LADSPA_IS_PORT_CONTROL(port_descriptor (i))){

                        child = new XMLNode("Port");
                        snprintf(buf, sizeof(buf), "%u", i);
                        child->add_property("number", string(buf));
                        snprintf(buf, sizeof(buf), "%+f", _shadow_data[i]);
                        child->add_property("value", string(buf));
                        root->add_child_nocopy (*child);
                }
        }
}

int
LadspaPlugin::set_state (const XMLNode& node, int version)
{
        if (version < 3000) {
                return set_state_2X (node, version);
        }

#ifndef NO_PLUGIN_STATE
        XMLNodeList nodes;
        XMLProperty *prop;
        XMLNodeConstIterator iter;
        XMLNode *child;
        const char *port;
        const char *data;
        uint32_t port_id;
#endif
        LocaleGuard lg (X_("C"));

        if (node.name() != state_node_name()) {
                error << _("Bad node sent to LadspaPlugin::set_state") << endmsg;
                return -1;
        }

#ifndef NO_PLUGIN_STATE

        nodes = node.children ("Port");

        for (iter = nodes.begin(); iter != nodes.end(); ++iter) {

                child = *iter;

                if ((prop = child->property("number")) != 0) {
                        port = prop->value().c_str();
                } else {
                        warning << _("LADSPA: no ladspa port number") << endmsg;
                        continue;
                }
                if ((prop = child->property("value")) != 0) {
                        data = prop->value().c_str();
                } else {
                        warning << _("LADSPA: no ladspa port data") << endmsg;
                        continue;
                }

                sscanf (port, "%" PRIu32, &port_id);
                set_parameter (port_id, atof(data));
        }
#endif

        latency_compute_run ();

        return Plugin::set_state (node, version);
}

int
LadspaPlugin::set_state_2X (const XMLNode& node, int /* version */)
{
#ifndef NO_PLUGIN_STATE
        XMLNodeList nodes;
        XMLProperty *prop;
        XMLNodeConstIterator iter;
        XMLNode *child;
        const char *port;
        const char *data;
        uint32_t port_id;
#endif
        LocaleGuard lg (X_("C"));

        if (node.name() != state_node_name()) {
                error << _("Bad node sent to LadspaPlugin::set_state") << endmsg;
                return -1;
        }

#ifndef NO_PLUGIN_STATE
        nodes = node.children ("port");

        for(iter = nodes.begin(); iter != nodes.end(); ++iter){

                child = *iter;

                if ((prop = child->property("number")) != 0) {
                        port = prop->value().c_str();
                } else {
                        warning << _("LADSPA: no ladspa port number") << endmsg;
                        continue;
                }
                if ((prop = child->property("value")) != 0) {
                        data = prop->value().c_str();
                } else {
                        warning << _("LADSPA: no ladspa port data") << endmsg;
                        continue;
                }

                sscanf (port, "%" PRIu32, &port_id);
                set_parameter (port_id, atof(data));
        }

        latency_compute_run ();
#endif

        return 0;
}

int
LadspaPlugin::get_parameter_descriptor (uint32_t which, ParameterDescriptor& desc) const
{
        LADSPA_PortRangeHint prh;

        prh  = port_range_hints()[which];


        if (LADSPA_IS_HINT_BOUNDED_BELOW(prh.HintDescriptor)) {
                desc.min_unbound = false;
                if (LADSPA_IS_HINT_SAMPLE_RATE(prh.HintDescriptor)) {
                        desc.lower = prh.LowerBound * _session.frame_rate();
                } else {
                        desc.lower = prh.LowerBound;
                }
        } else {
                desc.min_unbound = true;
                desc.lower = 0;
        }


        if (LADSPA_IS_HINT_BOUNDED_ABOVE(prh.HintDescriptor)) {
                desc.max_unbound = false;
                if (LADSPA_IS_HINT_SAMPLE_RATE(prh.HintDescriptor)) {
                        desc.upper = prh.UpperBound * _session.frame_rate();
                } else {
                        desc.upper = prh.UpperBound;
                }
        } else {
                desc.max_unbound = true;
                desc.upper = 4; /* completely arbitrary */
        }

        if (LADSPA_IS_HINT_HAS_DEFAULT (prh.HintDescriptor)) {
                desc.normal = _default_value(which);
        } else {
                /* if there is no explicit hint for the default
                 * value, use lower bound. This is not great but
                 * better than just assuming '0' which may be out-of range.
                 */
                desc.normal = desc.lower;
        }

        desc.toggled = LADSPA_IS_HINT_TOGGLED (prh.HintDescriptor);
        desc.logarithmic = LADSPA_IS_HINT_LOGARITHMIC (prh.HintDescriptor);
        desc.sr_dependent = LADSPA_IS_HINT_SAMPLE_RATE (prh.HintDescriptor);
        desc.integer_step = LADSPA_IS_HINT_INTEGER (prh.HintDescriptor);

        desc.label = port_names()[which];

        desc.scale_points = get_scale_points(which);
        desc.update_steps();

        return 0;
}

string
LadspaPlugin::describe_parameter (Evoral::Parameter which)
{
        if (which.type() == PluginAutomation && which.id() < parameter_count()) {
                return port_names()[which.id()];
        } else {
                return "??";
        }
}

ARDOUR::framecnt_t
LadspaPlugin::signal_latency () const
{
        if (_user_latency) {
                return _user_latency;
        }

        if (_latency_control_port) {
                return (framecnt_t) floor (*_latency_control_port);
        } else {
                return 0;
        }
}

set<Evoral::Parameter>
LadspaPlugin::automatable () const
{
        set<Evoral::Parameter> ret;

        for (uint32_t i = 0; i < parameter_count(); ++i){
                if (LADSPA_IS_PORT_INPUT(port_descriptor (i)) &&
                    LADSPA_IS_PORT_CONTROL(port_descriptor (i))){

                        ret.insert (ret.end(), Evoral::Parameter(PluginAutomation, 0, i));
                }
        }

        return ret;
}

int
LadspaPlugin::connect_and_run (BufferSet& bufs,
                ChanMapping in_map, ChanMapping out_map,
                pframes_t nframes, framecnt_t offset)
{
        Plugin::connect_and_run (bufs, in_map, out_map, nframes, offset);

        cycles_t now;
        cycles_t then = get_cycles ();

        BufferSet& silent_bufs  = _session.get_silent_buffers(ChanCount(DataType::AUDIO, 1));
        BufferSet& scratch_bufs = _session.get_scratch_buffers(ChanCount(DataType::AUDIO, 1));

        uint32_t audio_in_index  = 0;
        uint32_t audio_out_index = 0;
        bool valid;
        for (uint32_t port_index = 0; port_index < parameter_count(); ++port_index) {
                if (LADSPA_IS_PORT_AUDIO(port_descriptor(port_index))) {
                        if (LADSPA_IS_PORT_INPUT(port_descriptor(port_index))) {
                                const uint32_t buf_index = in_map.get(DataType::AUDIO, audio_in_index++, &valid);
                                connect_port(port_index,
                                             valid ? bufs.get_audio(buf_index).data(offset)
                                                   : silent_bufs.get_audio(0).data(offset));
                        } else if (LADSPA_IS_PORT_OUTPUT(port_descriptor(port_index))) {
                                const uint32_t buf_index = out_map.get(DataType::AUDIO, audio_out_index++, &valid);
                                connect_port(port_index,
                                             valid ? bufs.get_audio(buf_index).data(offset)
                                                   : scratch_bufs.get_audio(0).data(offset));
                        }
                }
        }

        run_in_place (nframes);
        now = get_cycles ();
        set_cycles ((uint32_t) (now - then));

        return 0;
}

bool
LadspaPlugin::parameter_is_control (uint32_t param) const
{
        return LADSPA_IS_PORT_CONTROL(port_descriptor (param));
}

bool
LadspaPlugin::parameter_is_audio (uint32_t param) const
{
        return LADSPA_IS_PORT_AUDIO(port_descriptor (param));
}

bool
LadspaPlugin::parameter_is_output (uint32_t param) const
{
        return LADSPA_IS_PORT_OUTPUT(port_descriptor (param));
}

bool
LadspaPlugin::parameter_is_input (uint32_t param) const
{
        return LADSPA_IS_PORT_INPUT(port_descriptor (param));
}

void
LadspaPlugin::print_parameter (uint32_t param, char *buf, uint32_t len) const
{
        if (buf && len) {
                if (param < parameter_count()) {
                        snprintf (buf, len, "%.3f", get_parameter (param));
                } else {
                        strcat (buf, "0");
                }
        }
}

boost::shared_ptr<ScalePoints>
LadspaPlugin::get_scale_points(uint32_t port_index) const
{
        boost::shared_ptr<ScalePoints> ret;
#ifdef HAVE_LRDF
        const uint32_t id     = atol(unique_id().c_str());
        lrdf_defaults* points = lrdf_get_scale_values(id, port_index);

        if (!points) {
                return ret;
        }

        ret = boost::shared_ptr<ScalePoints>(new ScalePoints());

        for (uint32_t i = 0; i < points->count; ++i) {
                ret->insert(make_pair(points->items[i].label,
                                      points->items[i].value));
        }

        lrdf_free_setting_values(points);
#endif
        return ret;
}

void
LadspaPlugin::run_in_place (pframes_t nframes)
{
        for (uint32_t i = 0; i < parameter_count(); ++i) {
                if (LADSPA_IS_PORT_INPUT(port_descriptor (i)) && LADSPA_IS_PORT_CONTROL(port_descriptor (i))) {
                        _control_data[i] = _shadow_data[i];
                }
        }

        assert (_was_activated);

        _descriptor->run (_handle, nframes);
}

void
LadspaPlugin::latency_compute_run ()
{
        if (!_latency_control_port) {
                return;
        }

        /* we need to run the plugin so that it can set its latency
           parameter.
        */

        activate ();

        uint32_t port_index = 0;
        uint32_t in_index = 0;
        uint32_t out_index = 0;
        const framecnt_t bufsize = 1024;
        LADSPA_Data buffer[bufsize];

        memset(buffer,0,sizeof(LADSPA_Data)*bufsize);

        /* Note that we've already required that plugins
           be able to handle in-place processing.
        */

        port_index = 0;

        while (port_index < parameter_count()) {
                if (LADSPA_IS_PORT_AUDIO (port_descriptor (port_index))) {
                        if (LADSPA_IS_PORT_INPUT (port_descriptor (port_index))) {
                                connect_port (port_index, buffer);
                                in_index++;
                        } else if (LADSPA_IS_PORT_OUTPUT (port_descriptor (port_index))) {
                                connect_port (port_index, buffer);
                                out_index++;
                        }
                }
                port_index++;
        }

        run_in_place (bufsize);
        deactivate ();
}

PluginPtr
LadspaPluginInfo::load (Session& session)
{
        try {
                PluginPtr plugin (new LadspaPlugin (path, session.engine(), session, index, session.frame_rate()));
                plugin->set_info(PluginInfoPtr(new LadspaPluginInfo(*this)));
                return plugin;
        }

        catch (failed_constructor &err) {
                return PluginPtr ((Plugin*) 0);
        }
}

LadspaPluginInfo::LadspaPluginInfo()
{
       type = ARDOUR::LADSPA;
}


void
LadspaPlugin::find_presets ()
{
#ifdef HAVE_LRDF
        uint32_t id;
        std::string unique (unique_id());

        if (!isdigit (unique[0])) {
                return;
        }

        id = atol (unique.c_str());

        lrdf_uris* set_uris = lrdf_get_setting_uris(id);

        if (set_uris) {
                for (uint32_t i = 0; i < (uint32_t) set_uris->count; ++i) {
                        if (char* label = lrdf_get_label(set_uris->items[i])) {
                                PresetRecord rec (set_uris->items[i], label);
                                _presets.insert (make_pair (set_uris->items[i], rec));
                        }
                }
                lrdf_free_uris(set_uris);
        }
#endif
}


bool
LadspaPlugin::load_preset (PresetRecord r)
{
#ifdef HAVE_LRDF
        lrdf_defaults* defs = lrdf_get_setting_values (r.uri.c_str());

        if (defs) {
                for (uint32_t i = 0; i < (uint32_t) defs->count; ++i) {
                        if (parameter_is_input (defs->items[i].pid)) {
                                set_parameter(defs->items[i].pid, defs->items[i].value);
                        }
                }
                lrdf_free_setting_values(defs);
        }

        Plugin::load_preset (r);
#endif
        return true;
}

#ifdef HAVE_LRDF
/* XXX: should be in liblrdf */
static void
lrdf_remove_preset (const char* /*source*/, const char *setting_uri)
{
        lrdf_statement p;
        lrdf_statement *q;
        lrdf_statement *i;
        char setting_uri_copy[64];
        char buf[64];

        strncpy(setting_uri_copy, setting_uri, sizeof(setting_uri_copy));

        p.subject = setting_uri_copy;
        strncpy(buf, LADSPA_BASE "hasPortValue", sizeof(buf));
        p.predicate = buf;
        p.object = NULL;
        q = lrdf_matches(&p);

        p.predicate = NULL;
        p.object = NULL;
        for (i = q; i; i = i->next) {
                p.subject = i->object;
                lrdf_remove_matches(&p);
        }

        lrdf_free_statements(q);

        p.subject = NULL;
        strncpy(buf, LADSPA_BASE "hasSetting", sizeof(buf));
        p.predicate = buf;
        p.object = setting_uri_copy;
        lrdf_remove_matches(&p);

        p.subject = setting_uri_copy;
        p.predicate = NULL;
        p.object = NULL;
        lrdf_remove_matches (&p);
}
#endif

void
LadspaPlugin::do_remove_preset (string name)
{
#ifdef HAVE_LRDF
        string const envvar = preset_envvar ();
        if (envvar.empty()) {
                warning << _("Could not locate HOME.  Preset not removed.") << endmsg;
                return;
        }

        Plugin::PresetRecord const * p = preset_by_label (name);
        if (!p) {
                return;
        }

        string const source = preset_source (envvar);
        lrdf_remove_preset (source.c_str(), p->uri.c_str ());

        write_preset_file (envvar);
#endif
}

string
LadspaPlugin::preset_envvar () const
{
        char* envvar;
        if ((envvar = getenv ("HOME")) == 0) {
                return "";
        }

        return envvar;
}

string
LadspaPlugin::preset_source (string envvar) const
{
        return string_compose ("file:%1/.ladspa/rdf/ardour-presets.n3", envvar);
}

bool
LadspaPlugin::write_preset_file (string envvar)
{
#ifdef HAVE_LRDF
        string path = string_compose("%1/.ladspa", envvar);
        if (g_mkdir_with_parents (path.c_str(), 0775)) {
                warning << string_compose(_("Could not create %1.  Preset not saved. (%2)"), path, strerror(errno)) << endmsg;
                return false;
        }

        path += "/rdf";
        if (g_mkdir_with_parents (path.c_str(), 0775)) {
                warning << string_compose(_("Could not create %1.  Preset not saved. (%2)"), path, strerror(errno)) << endmsg;
                return false;
        }

        string const source = preset_source (envvar);

        if (lrdf_export_by_source (source.c_str(), source.substr(5).c_str())) {
                warning << string_compose(_("Error saving presets file %1."), source) << endmsg;
                return false;
        }

        return true;
#else
        return false;
#endif
}

string
LadspaPlugin::do_save_preset (string name)
{
#ifdef HAVE_LRDF
        /* make a vector of pids that are input parameters */
        vector<int> input_parameter_pids;
        for (uint32_t i = 0; i < parameter_count(); ++i) {
                if (parameter_is_input (i)) {
                        input_parameter_pids.push_back (i);
                }
        }

        std::string unique (unique_id());

        if (!isdigit (unique[0])) {
                return "";
        }

        uint32_t const id = atol (unique.c_str());

        lrdf_defaults defaults;
        defaults.count = input_parameter_pids.size ();
        std::vector<lrdf_portvalue> portvalues(input_parameter_pids.size());
        defaults.items = &portvalues[0];

        for (vector<int>::size_type i = 0; i < input_parameter_pids.size(); ++i) {
                portvalues[i].pid = input_parameter_pids[i];
                portvalues[i].value = get_parameter (input_parameter_pids[i]);
        }

        string const envvar = preset_envvar ();
        if (envvar.empty()) {
                warning << _("Could not locate HOME.  Preset not saved.") << endmsg;
                return "";
        }

        string const source = preset_source (envvar);

        char* uri_char = lrdf_add_preset (source.c_str(), name.c_str(), id, &defaults);
        string uri (uri_char);
        free (uri_char);

        if (!write_preset_file (envvar)) {
                return "";
        }

        return uri;
#else
        return string();
#endif
}

LADSPA_PortDescriptor
LadspaPlugin::port_descriptor (uint32_t i) const
{
        if (i < _descriptor->PortCount) {               
                return _descriptor->PortDescriptors[i];
        }
        
        warning << "LADSPA plugin port index " << i << " out of range." << endmsg;
        return 0;
}