Fully implement the CLAP params extension

src/plugin/bridges/clap-impls/plugin-proxy.cpp

@@ -22,7 +22,9 @@ ClapHostExtensions::ClapHostExtensions(const clap_host& host) noexcept
     : audio_ports(static_cast<const clap_host_audio_ports_t*>(
           host.get_extension(&host, CLAP_EXT_AUDIO_PORTS))),
       note_ports(static_cast<const clap_host_note_ports_t*>(
-          host.get_extension(&host, CLAP_EXT_NOTE_PORTS))) {}
+          host.get_extension(&host, CLAP_EXT_NOTE_PORTS))),
+      params(static_cast<const clap_host_params_t*>(
+          host.get_extension(&host, CLAP_EXT_PARAMS))) {}
 
 ClapHostExtensions::ClapHostExtensions() noexcept {}
 
@@ -30,7 +32,8 @@ clap::host::SupportedHostExtensions ClapHostExtensions::supported()
     const noexcept {
     return clap::host::SupportedHostExtensions{
         .supports_audio_ports = audio_ports != nullptr,
-        .supports_note_ports = note_ports != nullptr};
+        .supports_note_ports = note_ports != nullptr,
+        .supports_params = params != nullptr};
 }
 
 clap_plugin_proxy::clap_plugin_proxy(ClapPluginBridge& bridge,
@@ -63,6 +66,14 @@ clap_plugin_proxy::clap_plugin_proxy(ClapPluginBridge& bridge,
           .count = ext_note_ports_count,
           .get = ext_note_ports_get,
       }),
+      ext_params_vtable(clap_plugin_params_t{
+          .count = ext_params_count,
+          .get_info = ext_params_get_info,
+          .get_value = ext_params_get_value,
+          .value_to_text = ext_params_value_to_text,
+          .text_to_value = ext_params_text_to_value,
+          .flush = ext_params_flush,
+      }),
       // These function objects are relatively large, and we probably won't be
       // getting that many of them
       pending_callbacks_(128) {}
@@ -196,6 +207,9 @@ clap_plugin_proxy::plugin_get_extension(const struct clap_plugin* plugin,
     } else if (self->supported_extensions_.supports_note_ports &&
                strcmp(id, CLAP_EXT_NOTE_PORTS) == 0) {
         extension_ptr = &self->ext_note_ports_vtable;
+    } else if (self->supported_extensions_.supports_params &&
+               strcmp(id, CLAP_EXT_PARAMS) == 0) {
+        extension_ptr = &self->ext_params_vtable;
     }
 
     self->bridge_.logger_.log_extension_query("clap_plugin::get_extension",
@@ -284,3 +298,113 @@ clap_plugin_proxy::ext_note_ports_get(const clap_plugin_t* plugin,
         return false;
     }
 }
+
+uint32_t CLAP_ABI
+clap_plugin_proxy::ext_params_count(const clap_plugin_t* plugin) {
+    assert(plugin && plugin->plugin_data);
+    auto self = static_cast<const clap_plugin_proxy*>(plugin->plugin_data);
+
+    return self->bridge_.send_main_thread_message(
+        clap::ext::params::plugin::Count{.instance_id = self->instance_id()});
+}
+
+bool CLAP_ABI
+clap_plugin_proxy::ext_params_get_info(const clap_plugin_t* plugin,
+                                       uint32_t param_index,
+                                       clap_param_info_t* param_info) {
+    assert(plugin && plugin->plugin_data && param_info);
+    auto self = static_cast<const clap_plugin_proxy*>(plugin->plugin_data);
+
+    const clap::ext::params::plugin::GetInfoResponse response =
+        self->bridge_.send_main_thread_message(
+            clap::ext::params::plugin::GetInfo{
+                .instance_id = self->instance_id(),
+                .param_index = param_index});
+    if (response.result) {
+        response.result->reconstruct(*param_info);
+
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool CLAP_ABI
+clap_plugin_proxy::ext_params_get_value(const clap_plugin_t* plugin,
+                                        clap_id param_id,
+                                        double* value) {
+    assert(plugin && plugin->plugin_data && value);
+    auto self = static_cast<const clap_plugin_proxy*>(plugin->plugin_data);
+
+    const clap::ext::params::plugin::GetValueResponse response =
+        self->bridge_.send_main_thread_message(
+            clap::ext::params::plugin::GetValue{
+                .instance_id = self->instance_id(), .param_id = param_id});
+    if (response.result) {
+        *value = *response.result;
+
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool CLAP_ABI
+clap_plugin_proxy::ext_params_value_to_text(const clap_plugin_t* plugin,
+                                            clap_id param_id,
+                                            double value,
+                                            char* display,
+                                            uint32_t size) {
+    assert(plugin && plugin->plugin_data && display);
+    auto self = static_cast<const clap_plugin_proxy*>(plugin->plugin_data);
+
+    const clap::ext::params::plugin::ValueToTextResponse response =
+        self->bridge_.send_main_thread_message(
+            clap::ext::params::plugin::ValueToText{
+                .instance_id = self->instance_id(),
+                .param_id = param_id,
+                .value = value});
+    if (response.result) {
+        strlcpy_buffer(display, *response.result, size);
+
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool CLAP_ABI
+clap_plugin_proxy::ext_params_text_to_value(const clap_plugin_t* plugin,
+                                            clap_id param_id,
+                                            const char* display,
+                                            double* value) {
+    assert(plugin && plugin->plugin_data && display && value);
+    auto self = static_cast<const clap_plugin_proxy*>(plugin->plugin_data);
+
+    const clap::ext::params::plugin::TextToValueResponse response =
+        self->bridge_.send_main_thread_message(
+            clap::ext::params::plugin::TextToValue{
+                .instance_id = self->instance_id(),
+                .param_id = param_id,
+                .display = display});
+    if (response.result) {
+        *value = *response.result;
+
+        return true;
+    } else {
+        return false;
+    }
+}
+
+void CLAP_ABI
+clap_plugin_proxy::ext_params_flush(const clap_plugin_t* plugin,
+                                    const clap_input_events_t* in,
+                                    const clap_output_events_t* out) {
+    assert(plugin && plugin->plugin_data);
+    auto self = static_cast<const clap_plugin_proxy*>(plugin->plugin_data);
+
+    // This may also be called on the audio thread and it is never called during
+    // process, so always using the audio thread here is safe
+    self->bridge_.send_audio_thread_message(
+        clap::ext::params::plugin::Flush{.instance_id = self->instance_id()});
+}

src/plugin/bridges/clap-impls/plugin-proxy.h

@@ -21,6 +21,7 @@
 
 #include <clap/ext/audio-ports.h>
 #include <clap/ext/note-ports.h>
+#include <clap/ext/params.h>
 #include <clap/plugin.h>
 #include <rigtorp/MPMCQueue.h>
 #include <function2/function2.hpp>
@@ -58,6 +59,7 @@ struct ClapHostExtensions {
 
     const clap_host_audio_ports_t* audio_ports = nullptr;
     const clap_host_note_ports_t* note_ports = nullptr;
+    const clap_host_params_t* params = nullptr;
 };
 
 /**
@@ -139,6 +141,26 @@ class clap_plugin_proxy {
                                             bool is_input,
                                             clap_note_port_info_t* info);
 
+    static uint32_t CLAP_ABI ext_params_count(const clap_plugin_t* plugin);
+    static bool CLAP_ABI ext_params_get_info(const clap_plugin_t* plugin,
+                                             uint32_t param_index,
+                                             clap_param_info_t* param_info);
+    static bool CLAP_ABI ext_params_get_value(const clap_plugin_t* plugin,
+                                              clap_id param_id,
+                                              double* value);
+    static bool CLAP_ABI ext_params_value_to_text(const clap_plugin_t* plugin,
+                                                  clap_id param_id,
+                                                  double value,
+                                                  char* display,
+                                                  uint32_t size);
+    static bool CLAP_ABI ext_params_text_to_value(const clap_plugin_t* plugin,
+                                                  clap_id param_id,
+                                                  const char* display,
+                                                  double* value);
+    static void CLAP_ABI ext_params_flush(const clap_plugin_t* plugin,
+                                          const clap_input_events_t* in,
+                                          const clap_output_events_t* out);
+
     /**
      * Asynchronously run a function on the host's main thread, returning the
      * result as a future.
@@ -207,6 +229,7 @@ class clap_plugin_proxy {
     // `clap_plugin::init()`.
     const clap_plugin_audio_ports ext_audio_ports_vtable;
     const clap_plugin_note_ports ext_note_ports_vtable;
+    const clap_plugin_params ext_params_vtable;
 
     /**
      * The extensions supported by the bridged plugin. Set after a successful

src/plugin/bridges/clap.cpp

@@ -148,6 +148,48 @@ ClapPluginBridge::ClapPluginBridge(const ghc::filesystem::path& plugin_path)
 
                     return Ack{};
                 },
+                [&](const clap::ext::params::host::Rescan& request)
+                    -> clap::ext::params::host::Rescan::Response {
+                    const auto& [plugin_proxy, _] =
+                        get_proxy(request.owner_instance_id);
+
+                    plugin_proxy
+                        .run_on_main_thread(
+                            [&, host = plugin_proxy.host_,
+                             params = plugin_proxy.host_extensions_.params]() {
+                                params->rescan(host, request.flags);
+                            })
+                        .wait();
+
+                    return Ack{};
+                },
+                [&](const clap::ext::params::host::Clear& request)
+                    -> clap::ext::params::host::Clear::Response {
+                    const auto& [plugin_proxy, _] =
+                        get_proxy(request.owner_instance_id);
+
+                    plugin_proxy
+                        .run_on_main_thread(
+                            [&, host = plugin_proxy.host_,
+                             params = plugin_proxy.host_extensions_.params]() {
+                                params->clear(host, request.param_id,
+                                              request.flags);
+                            })
+                        .wait();
+
+                    return Ack{};
+                },
+                [&](const clap::ext::params::host::RequestFlush& request)
+                    -> clap::ext::params::host::RequestFlush::Response {
+                    const auto& [plugin_proxy, _] =
+                        get_proxy(request.owner_instance_id);
+
+                    // This doesn't need to be called from the main thread
+                    plugin_proxy.host_extensions_.params->request_flush(
+                        plugin_proxy.host_);
+
+                    return Ack{};
+                },
             });
     });
 }