very, very simple WP with midi CC out

2024-10-09 02:01:23 +02:00
commit 3d6fc151f1
126 changed files with 19539 additions and 0 deletions
@@ -0,0 +1,151 @@
+#pragma once
+#include <libremidi/backends/alsa_seq/helpers.hpp>
+#include <libremidi/backends/alsa_seq_ump/config.hpp>
+#include <libremidi/backends/alsa_seq_ump/helpers.hpp>
+#include <libremidi/detail/midi_out.hpp>
+#include <libremidi/detail/ump_stream.hpp>
+
+namespace libremidi::alsa_seq_ump
+{
+
+class midi_out_impl final
+    : public midi2::out_api
+    , private alsa_seq::alsa_data
+    , public error_handler
+{
+public:
+  struct
+      : libremidi::output_configuration
+      , alsa_seq_ump::output_configuration
+  {
+  } configuration;
+
+  midi_out_impl(
+      libremidi::output_configuration&& conf, alsa_seq_ump::output_configuration&& apiconf)
+      : configuration{std::move(conf), std::move(apiconf)}
+  {
+    assert(snd.seq.ump.available);
+    if (init_client(configuration) < 0)
+    {
+      error<driver_error>(
+          this->configuration,
+          "midi_in_alsa::initialize: error creating ALSA sequencer client "
+          "object.");
+      return;
+    }
+
+    if (snd.midi.event_new(this->bufferSize, &this->coder) < 0)
+    {
+      error<driver_error>(
+          this->configuration,
+          "midi_out_alsa::initialize: error initializing MIDI event "
+          "parser.");
+      return;
+    }
+    snd.midi.event_init(this->coder);
+  }
+
+  ~midi_out_impl() override
+  {
+    // Close a connection if it exists.
+    midi_out_impl::close_port();
+
+    // Cleanup.
+    if (this->vport >= 0)
+      snd.seq.delete_port(this->seq, this->vport);
+    if (this->coder)
+      snd.midi.event_free(this->coder);
+
+    if (!configuration.context)
+      snd.seq.close(this->seq);
+  }
+
+  libremidi::API get_current_api() const noexcept override { return libremidi::API::ALSA_SEQ; }
+
+  [[nodiscard]] int create_port(std::string_view portName)
+  {
+    return alsa_data::create_port(
+        *this, portName,
+        SND_SEQ_PORT_CAP_READ | SND_SEQ_PORT_CAP_SUBS_READ | SND_SEQ_PORT_CAP_UMP_ENDPOINT,
+        SND_SEQ_PORT_TYPE_MIDI_GENERIC | SND_SEQ_PORT_TYPE_APPLICATION, std::nullopt);
+  }
+
+  bool open_port(const output_port& p, std::string_view portName) override
+  {
+    unsigned int nSrc = this->get_port_count(SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_SUBS_WRITE);
+    if (nSrc < 1)
+    {
+      error<no_devices_found_error>(
+          this->configuration, "midi_out_alsa::open_port: no MIDI output sources found!");
+      return false;
+    }
+
+    auto sink = get_port_info(p);
+    if (!sink)
+      return false;
+
+    if (int err = create_port(portName); err < 0)
+    {
+      error<driver_error>(configuration, "midi_out_alsa::create_port: ALSA error creating port.");
+      return false;
+    }
+
+    snd_seq_addr_t source{
+        .client = (unsigned char)snd.seq.client_id(this->seq), .port = (unsigned char)this->vport};
+    if (int err = create_connection(*this, source, *sink, true); err < 0)
+    {
+      error<driver_error>(
+          configuration, "midi_out_alsa::create_port: ALSA error making port connection.");
+      return false;
+    }
+
+    return true;
+  }
+
+  bool open_virtual_port(std::string_view portName) override
+  {
+    if (int err = create_port(portName); err < 0)
+      return false;
+    return true;
+  }
+
+  void close_port() override { unsubscribe(); }
+
+  void set_client_name(std::string_view clientName) override
+  {
+    alsa_data::set_client_name(clientName);
+  }
+
+  void set_port_name(std::string_view portName) override { alsa_data::set_port_name(portName); }
+
+  void send_ump(const uint32_t* ump_stream, std::size_t count) override
+  {
+    snd_seq_ump_event_t ev;
+
+    memset(&ev, 0, sizeof(snd_seq_ump_event_t));
+    snd_seq_ev_set_ump(&ev);
+    snd_seq_ev_set_source(&ev, this->vport);
+    snd_seq_ev_set_subs(&ev);
+    snd_seq_ev_set_direct(&ev);
+
+    auto write_func = [this, &ev](const uint32_t* ump, int64_t bytes) {
+      std::memcpy(ev.ump, ump, bytes);
+      const int result = snd.seq.ump.event_output_direct(this->seq, &ev);
+      if (result < 0)
+      {
+        warning(
+            this->configuration,
+            "midi_out_alsa::send_message: error sending MIDI message to port.");
+        return libremidi::segmentation_error::other;
+      }
+      return libremidi::segmentation_error::no_error;
+    };
+    segment_ump_stream(ump_stream, count, write_func, []() {});
+
+    snd.seq.drain_output(this->seq);
+  }
+
+private:
+  unsigned int bufferSize{32};
+};
+}