components/arc/timer/arc_timer_traits.cc

// Copyright 2018 The Chromium 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 <utility>

#include "base/posix/unix_domain_socket.h"
#include "components/arc/timer/arc_timer_traits.h"
#include "mojo/public/cpp/system/handle.h"
#include "mojo/public/cpp/system/platform_handle.h"

namespace {

// Unwraps a mojo handle to a file descriptor on the system.
base::ScopedFD UnwrapPlatformHandle(mojo::ScopedHandle handle) {
  base::PlatformFile platform_file;
  if (mojo::UnwrapPlatformFile(std::move(handle), &platform_file) !=
      MOJO_RESULT_OK) {
    LOG(ERROR) << "Failed to unwrap mojo handle";
    return base::ScopedFD();
  }
  return base::ScopedFD(platform_file);
}

// Converts a system file descriptor to a mojo handle that can be sent to the
// host.
mojo::ScopedHandle WrapPlatformFd(base::ScopedFD scoped_fd) {
  mojo::ScopedHandle handle = mojo::WrapPlatformFile(scoped_fd.release());
  if (!handle.is_valid()) {
    LOG(ERROR) << "Failed to wrap platform handle";
    return mojo::ScopedHandle();
  }
  return handle;
}

}  // namespace

namespace mojo {

// static
arc::mojom::ClockId EnumTraits<arc::mojom::ClockId, int32_t>::ToMojom(
    int32_t clock_id) {
  switch (clock_id) {
    case CLOCK_REALTIME_ALARM:
      return arc::mojom::ClockId::REALTIME_ALARM;
    case CLOCK_BOOTTIME_ALARM:
      return arc::mojom::ClockId::BOOTTIME_ALARM;
  }
  NOTREACHED();
  return arc::mojom::ClockId::BOOTTIME_ALARM;
}

// static
bool EnumTraits<arc::mojom::ClockId, int32_t>::FromMojom(
    arc::mojom::ClockId input,
    int32_t* output) {
  switch (input) {
    case arc::mojom::ClockId::REALTIME_ALARM:
      *output = CLOCK_REALTIME_ALARM;
      return true;
    case arc::mojom::ClockId::BOOTTIME_ALARM:
      *output = CLOCK_BOOTTIME_ALARM;
      return true;
  }
  NOTREACHED();
  return false;
}

// static
arc::mojom::ClockId
StructTraits<arc::mojom::CreateTimerRequestDataView, arc::CreateTimerRequest>::
    clock_id(const arc::CreateTimerRequest& arc_timer_request) {
  return EnumTraits<arc::mojom::ClockId, int32_t>::ToMojom(
      arc_timer_request.clock_id);
}

// static
mojo::ScopedHandle
StructTraits<arc::mojom::CreateTimerRequestDataView, arc::CreateTimerRequest>::
    expiration_fd(arc::CreateTimerRequest& arc_timer_request) {
  return WrapPlatformFd(std::move(arc_timer_request.expiration_fd));
}

// static
bool StructTraits<
    arc::mojom::CreateTimerRequestDataView,
    arc::CreateTimerRequest>::Read(arc::mojom::CreateTimerRequestDataView input,
                                   arc::CreateTimerRequest* output) {
  if (!EnumTraits<arc::mojom::ClockId, int32_t>::FromMojom(input.clock_id(),
                                                           &output->clock_id)) {
    return false;
  }
  output->expiration_fd = UnwrapPlatformHandle(input.TakeExpirationFd());
  return true;
}

}  // namespace mojo