Add the basic MIDNAM support for LV2

cmake/SfizzConfig.cmake

@@ -48,6 +48,9 @@ else()
     target_link_libraries(sfizz-sndfile INTERFACE ${SNDFILE_LIBRARIES})
 endif()
 
+add_library(sfizz-pugixml STATIC "src/external/pugixml/src/pugixml.cpp")
+target_include_directories(sfizz-pugixml PUBLIC "src/external/pugixml/src")
+
 # If we build with Clang use libc++
 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT ANDROID)
     set(USE_LIBCPP ON CACHE BOOL "Use libc++ with clang")

lv2/CMakeLists.txt

@@ -13,7 +13,7 @@ set (LV2PLUGIN_TTL_SRC_FILES
 )
 add_library (${LV2PLUGIN_PRJ_NAME} SHARED ${PROJECT_NAME}.c ${LV2PLUGIN_TTL_SRC_FILES})
 target_link_libraries (${LV2PLUGIN_PRJ_NAME} ${PROJECT_NAME}::${PROJECT_NAME})
-target_include_directories(${LV2PLUGIN_PRJ_NAME} PRIVATE .)
+target_include_directories(${LV2PLUGIN_PRJ_NAME} PRIVATE . external/ardour)
 sfizz_enable_lto_if_needed (${LV2PLUGIN_PRJ_NAME})
 
 # Remove the "lib" prefix, rename the target name and build it in the .lv build dir

lv2/sfizz.c

@@ -47,10 +47,13 @@
 #include <lv2/log/logger.h>
 #include <lv2/log/log.h>
 
+#include <ardour/lv2_extensions.h>
+
 #include <math.h>
 #include <sfizz.h>
 #include <stdbool.h>
 #include <stdlib.h>
+#include <stdatomic.h>
 #include <string.h>
 
 #define DEFAULT_SFZ_FILE "/home/paul/Documents/AVL_Percussions/AVL_Drumkits_Percussion-1.0-Alt.sfz"
@@ -90,6 +93,7 @@ typedef struct
     LV2_URID_Unmap *unmap;
     LV2_Worker_Schedule *worker;
     LV2_Log_Log *log;
+    LV2_Midnam *midnam;
 
     // Ports
     const LV2_Atom_Sequence *control_port;
@@ -145,6 +149,7 @@ typedef struct
     int max_block_size;
     int sample_counter;
     float sample_rate;
+    _Atomic(bool) must_update_midnam;
 } sfizz_plugin_t;
 
 enum
@@ -310,6 +315,9 @@ instantiate(const LV2_Descriptor *descriptor,
 
         if (!strcmp((**f).URI, LV2_LOG__log))
             self->log = (**f).data;
+
+        if (!strcmp((**f).URI, LV2_MIDNAM__update))
+            self->midnam = (**f).data;
     }
 
     // Setup the loggers
@@ -684,6 +692,11 @@ run(LV2_Handle instance, uint32_t sample_count)
 
     // Render the block
     sfizz_render_block(self->synth, self->output_buffers, 2, (int)sample_count);
+
+    if (self->midnam && atomic_exchange(&self->must_update_midnam, false))
+    {
+        self->midnam->update(self->midnam->handle);
+    }
 }
 
 static uint32_t
@@ -770,6 +783,8 @@ sfizz_lv2_update_file_info(sfizz_plugin_t* self, const char* file_path)
     lv2_log_note(&self->logger, "[sfizz] Number of masters: %d\n", sfizz_get_num_masters(self->synth));
     lv2_log_note(&self->logger, "[sfizz] Number of groups: %d\n", sfizz_get_num_groups(self->synth));
     lv2_log_note(&self->logger, "[sfizz] Number of regions: %d\n", sfizz_get_num_regions(self->synth));
+
+    atomic_store(&self->must_update_midnam, true);
 }
 
 static LV2_State_Status
@@ -1066,12 +1081,44 @@ work_response(LV2_Handle instance,
     return LV2_WORKER_SUCCESS;
 }
 
+static char *
+midnam_model(LV2_Handle instance)
+{
+    char *model = malloc(64);
+    if (!model)
+        return NULL;
+
+    sprintf(model, "Sfizz LV2:%p", instance);
+    return model;
+}
+
+static char *
+midnam_export(LV2_Handle instance)
+{
+    sfizz_plugin_t *self = (sfizz_plugin_t *)instance;
+
+    char *model = midnam_model(instance);
+    if (!model)
+        return NULL;
+
+    char *xml = sfizz_export_midnam(self->synth, model);
+    free(model);
+    return xml;
+}
+
+static void
+midnam_free(char *string)
+{
+    free(string);
+}
+
 static const void *
 extension_data(const char *uri)
 {
     static const LV2_Options_Interface options = {lv2_get_options, lv2_set_options};
     static const LV2_State_Interface state = {save, restore};
     static const LV2_Worker_Interface worker = {work, work_response, NULL};
+    static const LV2_Midnam_Interface midnam = {midnam_export, midnam_model, midnam_free};
 
     // Advertise the extensions we support
     if (!strcmp(uri, LV2_OPTIONS__interface))
@@ -1080,6 +1127,8 @@ extension_data(const char *uri)
         return &state;
     else if (!strcmp(uri, LV2_WORKER__interface))
         return &worker;
+    else if (!strcmp(uri, LV2_MIDNAM__interface))
+        return &midnam;
 
     return NULL;
 }

lv2/sfizz.ttl.in

@@ -5,7 +5,7 @@
 @prefix lv2:     <http://lv2plug.in/ns/lv2core#> .
 @prefix midi:    <http://lv2plug.in/ns/ext/midi#> .
 @prefix opts:    <http://lv2plug.in/ns/ext/options#> .
-@prefix patch: 	 <http://lv2plug.in/ns/ext/patch#> .
+@prefix patch:   <http://lv2plug.in/ns/ext/patch#> .
 @prefix pg:      <http://lv2plug.in/ns/ext/port-groups#> .
 @prefix pprop:   <http://lv2plug.in/ns/ext/port-props#> .
 @prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@@ -14,6 +14,10 @@
 @prefix units:   <http://lv2plug.in/ns/extensions/units#> .
 @prefix urid:    <http://lv2plug.in/ns/ext/urid#> .
 @prefix work:    <http://lv2plug.in/ns/ext/worker#> .
+@prefix midnam:  <http://ardour.org/lv2/midnam#> .
+
+midnam:interface a lv2:ExtensionData .
+midnam:update a lv2:Feature .
 
 <#config>
   a pg:Group ;
@@ -65,6 +69,9 @@
   lv2:optionalFeature lv2:hardRTCapable, opts:options ;
   lv2:extensionData opts:interface, state:interface, work:interface ;
 
+  lv2:optionalFeature midnam:update ;
+  lv2:extensionData midnam:interface ;
+
   patch:writable <@LV2PLUGIN_URI@:sfzfile> ;
 
   lv2:port [

src/CMakeLists.txt

@@ -30,7 +30,7 @@ target_sources(sfizz_static PRIVATE ${SFIZZ_SOURCES} sfizz/sfizz_wrapper.cpp)
 target_include_directories (sfizz_static PUBLIC .)
 target_include_directories (sfizz_static PUBLIC external)
 target_link_libraries (sfizz_static PUBLIC absl::strings absl::span)
-target_link_libraries (sfizz_static PRIVATE sfizz_parser absl::flat_hash_map Threads::Threads sfizz-sndfile)
+target_link_libraries (sfizz_static PRIVATE sfizz_parser absl::flat_hash_map Threads::Threads sfizz-sndfile sfizz-pugixml)
 
 add_library (sfizz::parser ALIAS sfizz_parser)
 add_library (sfizz::sfizz ALIAS sfizz_static)
@@ -47,7 +47,7 @@ if (SFIZZ_SHARED)
     target_sources(sfizz_shared PRIVATE ${SFIZZ_SOURCES} sfizz/sfizz_wrapper.cpp sfizz/sfizz.cpp)
     target_include_directories (sfizz_shared PRIVATE .)
     target_include_directories (sfizz_static PRIVATE external)
-    target_link_libraries (sfizz_shared PRIVATE absl::strings absl::span sfizz_parser absl::flat_hash_map Threads::Threads sfizz-sndfile)
+    target_link_libraries (sfizz_shared PRIVATE absl::strings absl::span sfizz_parser absl::flat_hash_map Threads::Threads sfizz-sndfile sfizz-pugixml)
     target_compile_definitions(sfizz_shared PRIVATE SFIZZ_EXPORT_SYMBOLS)
     set_target_properties (sfizz_shared PROPERTIES OUTPUT_NAME sfizz PUBLIC_HEADER "sfizz.h;sfizz.hpp")
     set_property (TARGET sfizz_shared PROPERTY SOVERSION ${PROJECT_VERSION_MAJOR})

src/sfizz.h

@@ -94,6 +94,16 @@ SFIZZ_EXPORTED_API int sfizz_get_num_masters(sfizz_synth_t* synth);
  * @return     int the number of curves
  */
 SFIZZ_EXPORTED_API int sfizz_get_num_curves(sfizz_synth_t* synth);
+/**
+ * @brief      Export a MIDI Name document describing the the currently loaded
+ *             SFZ file.
+ *
+ * @param      synth        The synth
+ * @param      model        the model name used if a non-empty string, otherwise generated
+ *
+ * @return     char* a newly allocated XML string, which must be freed after use
+ */
+SFIZZ_EXPORTED_API char* sfizz_export_midnam(sfizz_synth_t* synth, const char* model);
 /**
  * @brief      Returns the number of preloaded samples for the current SFZ file.
  *

src/sfizz/Synth.cpp

@@ -11,6 +11,7 @@
 #include "MidiState.h"
 #include "ScopedFTZ.h"
 #include "StringViewHelpers.h"
+#include "pugixml.hpp"
 #include "absl/algorithm/container.h"
 #include "absl/strings/str_replace.h"
 #include <algorithm>
@@ -577,6 +578,94 @@ int sfz::Synth::getNumCurves() const noexcept
     return numCurves;
 }
 
+std::string sfz::Synth::exportMidnam(absl::string_view model) const
+{
+    pugi::xml_document doc;
+
+    // TODO: perhaps define this somewhere, or use some metadata from the SFZ
+    const char *manufacturer = "Paul Ferrand";
+    const char *defaultModel = "Sfizz";
+
+    if (model.empty())
+        model = defaultModel;
+
+    doc.append_child(pugi::node_doctype).set_value(
+        "MIDINameDocument PUBLIC"
+        " \"-//MIDI Manufacturers Association//DTD MIDINameDocument 1.0//EN\""
+        " \"http://www.midi.org/dtds/MIDINameDocument10.dtd\"");
+
+    pugi::xml_node root = doc.append_child("MIDINameDocument");
+
+    root.append_child(pugi::node_comment)
+        .set_value("Generated by Sfizz for the current instrument");
+
+    root.append_child("Author");
+
+    pugi::xml_node device = root.append_child("MasterDeviceNames");
+    device.append_child("Manufacturer")
+        .append_child(pugi::node_pcdata).set_value(manufacturer);
+    device.append_child("Model")
+        .append_child(pugi::node_pcdata).set_value(std::string(model).c_str());
+
+    {
+        pugi::xml_node devmode = device.append_child("CustomDeviceMode");
+        devmode.append_attribute("Name").set_value("Default");
+
+        pugi::xml_node nsas = devmode.append_child("ChannelNameSetAssignments");
+        for (unsigned c = 0; c < 16; ++c) {
+            pugi::xml_node nsa = nsas.append_child("ChannelNameSetAssign");
+            nsa.append_attribute("Channel").set_value(std::to_string(c + 1).c_str());
+            nsa.append_attribute("NameSet").set_value("Play");
+        }
+    }
+
+    {
+        pugi::xml_node chns = device.append_child("ChannelNameSet");
+        chns.append_attribute("Name").set_value("Play");
+
+        pugi::xml_node acs = chns.append_child("AvailableForChannels");
+        for (unsigned c = 0; c < 16; ++c) {
+            pugi::xml_node ac = acs.append_child("AvailableChannel");
+            ac.append_attribute("Channel").set_value(std::to_string(c + 1).c_str());
+            ac.append_attribute("Available").set_value("true");
+        }
+
+        chns.append_child("UsesControlNameList")
+            .append_attribute("Name").set_value("Controls");
+    }
+
+    {
+        pugi::xml_node cns = device.append_child("ControlNameList");
+        cns.append_attribute("Name").set_value("Controls");
+        for (const CCNamePair& pair : ccNames) {
+            pugi::xml_node cn = cns.append_child("Control");
+            cn.append_attribute("Type").set_value("7bit");
+            cn.append_attribute("Number").set_value(std::to_string(pair.first).c_str());
+            cn.append_attribute("Name").set_value(pair.second.c_str());
+        }
+    }
+
+    ///
+    struct string_writer : pugi::xml_writer {
+        std::string result;
+
+        string_writer()
+        {
+            result.reserve(8192);
+        }
+
+        void write(const void* data, size_t size) override
+        {
+            result.append(static_cast<const char*>(data), size);
+        }
+    };
+
+    ///
+    string_writer writer;
+    doc.save(writer);
+    return std::move(writer.result);
+}
+
 const sfz::Region* sfz::Synth::getRegionView(int idx) const noexcept
 {
     return (size_t)idx < regions.size() ? regions[idx].get() : nullptr;

src/sfizz/Synth.h

@@ -111,6 +111,10 @@ public:
      * @return int
      */
     int getNumCurves() const noexcept;
+    /**
+     * @brief Export a MIDI Name document describing the loaded instrument
+     */
+    std::string exportMidnam(absl::string_view model = {}) const;
     /**
      * @brief Get a raw view into a specific region. This is mostly used
      * for testing.

src/sfizz/sfizz_wrapper.cpp

@@ -49,6 +49,11 @@ int sfizz_get_num_curves(sfizz_synth_t* synth)
     auto self = reinterpret_cast<sfz::Synth*>(synth);
     return self->getNumCurves();
 }
+char* sfizz_export_midnam(sfizz_synth_t* synth, const char* model)
+{
+    auto self = reinterpret_cast<sfz::Synth*>(synth);
+    return strdup(self->exportMidnam(model ? model : "").c_str());
+}
 size_t sfizz_get_num_preloaded_samples(sfizz_synth_t* synth)
 {
     auto self = reinterpret_cast<sfz::Synth*>(synth);