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 +1,171 @@
+#pragma once
+#include <libremidi/backends/pipewire/config.hpp>
+#include <libremidi/backends/pipewire/helpers.hpp>
+#include <libremidi/detail/midi_out.hpp>
+
+#include <readerwriterqueue.h>
+
+#include <semaphore>
+
+namespace libremidi
+{
+class midi_out_pipewire
+    : public midi1::out_api
+    , public pipewire_helpers
+    , public error_handler
+{
+public:
+  struct
+      : output_configuration
+      , pipewire_output_configuration
+  {
+  } configuration;
+
+  midi_out_pipewire(output_configuration&& conf, pipewire_output_configuration&& apiconf)
+      : configuration{std::move(conf), std::move(apiconf)}
+  {
+    create_context(*this);
+    create_filter(*this);
+  }
+
+  ~midi_out_pipewire() override
+  {
+    stop_thread();
+    do_close_port();
+    destroy_filter(*this);
+    destroy_context();
+  }
+
+  void set_client_name(std::string_view) override
+  {
+    warning(configuration, "midi_out_pipewire: set_client_name unsupported");
+  }
+
+  libremidi::API get_current_api() const noexcept override { return libremidi::API::PIPEWIRE; }
+
+  bool open_port(const output_port& out_port, std::string_view name) override
+  {
+    if (!create_local_port(*this, name, SPA_DIRECTION_OUTPUT))
+      return false;
+
+    this->filter->set_port_buffer(configuration.output_buffer_size);
+
+    if (!link_ports(*this, out_port))
+      return false;
+
+    start_thread();
+    return true;
+  }
+
+  bool open_virtual_port(std::string_view name) override
+  {
+    if (!create_local_port(*this, name, SPA_DIRECTION_OUTPUT))
+      return false;
+
+    this->filter->set_port_buffer(configuration.output_buffer_size);
+
+    start_thread();
+    return true;
+  }
+
+  void close_port() override
+  {
+    stop_thread();
+    do_close_port();
+  }
+
+  void set_port_name(std::string_view port_name) override { rename_port(port_name); }
+
+  int process(spa_io_position* pos)
+  {
+    m_process_clock.store(pos->clock.nsec, std::memory_order_relaxed);
+    const auto b = pw.filter_dequeue_buffer(this->filter->port);
+    if (!b)
+      return 1;
+
+    const auto buf = b->buffer;
+    const auto d = &buf->datas[0];
+
+    if (d->data == nullptr)
+      return 1;
+
+    spa_pod_builder build;
+    spa_zero(build);
+    spa_pod_builder_init(&build, d->data, d->maxsize);
+
+    spa_pod_frame f;
+    spa_pod_builder_push_sequence(&build, &f, 0);
+
+    // for all events
+    while (auto m_ptr = m_queue.peek())
+    {
+      auto& m = *m_ptr;
+      if (m.empty())
+      {
+        m_queue.pop();
+        continue;
+      }
+
+      // TODO why
+      if (m.bytes[0] == 0xff)
+      {
+        m_queue.pop();
+        continue;
+      }
+
+      spa_pod_builder_control(&build, m.timestamp, SPA_CONTROL_Midi);
+      int res = spa_pod_builder_bytes(&build, m.bytes.data(), m.bytes.size());
+
+      // Try again next buffer
+      if (res == -ENOSPC)
+        break;
+
+      m_queue.pop();
+    }
+    spa_pod_builder_pop(&build, &f);
+
+    int n_fill_frames = build.state.offset;
+    if (n_fill_frames > 0)
+    {
+      d->chunk->offset = 0;
+      d->chunk->stride = 1;
+      d->chunk->size = n_fill_frames;
+      b->size = n_fill_frames;
+
+      pw.filter_queue_buffer(this->filter->port, b);
+      return 0;
+    }
+
+    pw.filter_flush(this->filter->filter, true);
+
+    return 0;
+  }
+
+  void send_message(const unsigned char* message, size_t size) override
+  {
+    m_queue.enqueue(libremidi::message(midi_bytes{message, message + size}, 0));
+  }
+
+  int convert_timestamp(int64_t user) const noexcept
+  {
+    switch (configuration.timestamps)
+    {
+      case timestamp_mode::AudioFrame:
+        return static_cast<int>(user);
+
+      default:
+        // TODO
+        return 0;
+    }
+  }
+
+  void schedule_message(int64_t ts, const unsigned char* message, size_t size) override
+  {
+    m_queue.enqueue(
+        libremidi::message(midi_bytes{message, message + size}, convert_timestamp(ts)));
+  }
+
+  moodycamel::ReaderWriterQueue<libremidi::message> m_queue;
+  std::atomic_int64_t m_process_clock = 0;
+};
+}