src/input_sample/input_sample.cc

// Copyright 2022 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "input_sample.h"

#include <lib/async/cpp/task.h>
#include <lib/driver/component/cpp/service_client.h>

namespace input_sample {

zx::result<> InputSampleDriver::Start() {
  // Start sending fake reports
  input_report_readers_ =
      std::make_shared<input_report_reader::InputReportReaderManager<SampleInputReport>>();
  SendFakeReport();

  // Initialize the driver compat service context.
  compat::Context::ConnectAndCreate(
      &context(), dispatcher(),
      fit::bind_member<&InputSampleDriver::InitializeCompatService>(this));

  return zx::ok();
}

// Initialize the driver compat context and export `fuchsia.input.report` to devfs.
void InputSampleDriver::InitializeCompatService(
    zx::result<std::shared_ptr<compat::Context>> compat_result) {
  if (!compat_result.is_ok()) {
    FDF_SLOG(ERROR, "Failed to create compat context.",
             KV("status", compat_result.status_string()));
    node().reset();
    return;
  }
  compat_context_ = std::move(*compat_result);

   // Export to devfs.
  zx::result connection = this->context().incoming()->Connect<fuchsia_device_fs::Exporter>();
  if (connection.is_error()) {
    FDF_SLOG(ERROR, "Failed to connect to fuchsia_device_fs::Exporter",
             KV("status", connection.status_string()));
    node().reset();
    return;
  }
  fidl::WireSyncClient devfs_exporter{std::move(connection.value())};

  zx::result connector = devfs_connector_.Bind(dispatcher());
  if (connector.is_error()) {
    FDF_SLOG(ERROR, "Failed to bind devfs_connector: %s", KV("status", connector.status_string()));
    node().reset();
    return;
  }
  fidl::WireResult export_result = devfs_exporter->ExportV2(
      std::move(connector.value()),
      fidl::StringView::FromExternal(compat_context_->TopologicalPath(name())), "input-report",
      fuchsia_device_fs::ExportOptions());
  if (!export_result.ok()) {
    FDF_SLOG(ERROR, "Failed to export to devfs: %s", KV("status", export_result.status_string()));
    node().reset();
    return;
  }
  if (export_result.value().is_error()) {
    FDF_SLOG(ERROR, "Failed to export to devfs: %s",
             KV("status", zx_status_get_string(export_result.value().error_value())));
    node().reset();
    return;
  }
}

// Periodically send a new input report with fake data.
void InputSampleDriver::SendFakeReport() {
  // Update fake mouse report
  report_.event_time = zx::time(zx_clock_get_monotonic());
  report_.buttons++;
  report_.rel_x++;
  report_.rel_y++;

  // Send fake mouse report
  input_report_readers_->SendReportToAllReaders(report_);

  // Run again in 1 second
  async::PostDelayedTask(
      dispatcher(), [this]() mutable { SendFakeReport(); }, zx::sec(1));
}

void InputSampleDriver::Serve(fidl::ServerEnd<fuchsia_input_report::InputDevice> request) {
  InputSampleServer::BindDeviceClient(&logger(), dispatcher(), input_report_readers_,
                                      std::move(request));
}

}  // namespace input_sample

FUCHSIA_DRIVER_RECORD_CPP_V2(fdf::Record<input_sample::InputSampleDriver>);