src/devices/usb/lib/usb/align.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 SRC_DEVICES_USB_LIB_USB_ALIGN_H_
#define SRC_DEVICES_USB_LIB_USB_ALIGN_H_

// Returns min(`a` rounded up to `b * K`)
//   s.t.
//     K ∈ ℤ
//     K > 0
//     b > 0
//
// Do not copy these macros into new code, use fbl::round_up()
// from fbl/algorithm.h.
#define USB_ROUNDUP(a, b)       \
  ({                            \
    const __typeof(a) _a = (a); \
    const __typeof(b) _b = (b); \
    ((_a + _b - 1) / _b * _b);  \
  })

// Returns max(`a` rounded down to `b * K`)
//   s.t.
//     K ∈ ℤ
//     K > 0
//     b > 0
//
// Do not copy these macros into new code, use fbl::round_down()
// from fbl/algorithm.h.
#define USB_ROUNDDOWN(a, b)     \
  ({                            \
    const __typeof(a) _a = (a); \
    const __typeof(b) _b = (b); \
    _a - (_a % _b);             \
  })

#endif  // SRC_DEVICES_USB_LIB_USB_ALIGN_H_