sdk/lib/driver2/promise.h

// Copyright 2020 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.

#ifndef LIB_DRIVER2_PROMISE_H_
#define LIB_DRIVER2_PROMISE_H_

#include <fidl/fuchsia.driver.framework/cpp/wire.h>
#include <lib/driver2/namespace.h>
#include <lib/fpromise/promise.h>

namespace driver {

namespace internal {

// Connects to the given `path` in `ns`, and returns a fpromise::result containing a
// fidl::WireSharedClient on success.
template <typename T>
fpromise::result<fidl::WireSharedClient<T>, zx_status_t> ConnectWithResult(
    const driver::Namespace& ns, async_dispatcher_t* dispatcher, std::string_view path,
    fuchsia_io::wire::OpenFlags flags) {
  auto result = ns.Connect<T>(path, flags);
  if (result.is_error()) {
    return fpromise::error(result.status_value());
  }
  fidl::WireSharedClient<T> client(std::move(*result), dispatcher);
  return fpromise::ok(std::move(client));
}

}  // namespace internal

// Connects to the given `path` in `ns`, and returns a fpromise::promise containing a
// fidl::WireSharedClient on success.
template <typename T>
fpromise::promise<fidl::WireSharedClient<T>, zx_status_t> Connect(
    const driver::Namespace& ns, async_dispatcher_t* dispatcher,
    std::string_view path = fidl::DiscoverableProtocolDefaultPath<T>,
    fuchsia_io::wire::OpenFlags flags = fuchsia_io::wire::OpenFlags::kRightReadable) {
  return fpromise::make_result_promise(internal::ConnectWithResult<T>(ns, dispatcher, path, flags));
}

// Adds a child to `client`, using `args`. `controller` must be provided, but
// `node` is optional.
fpromise::promise<void, fuchsia_driver_framework::wire::NodeError> AddChild(
    fidl::WireSharedClient<fuchsia_driver_framework::Node>& client,
    fuchsia_driver_framework::wire::NodeAddArgs args,
    fidl::ServerEnd<fuchsia_driver_framework::NodeController> controller,
    fidl::ServerEnd<fuchsia_driver_framework::Node> node);

}  // namespace driver

#endif  // LIB_DRIVER2_PROMISE_H_