Luna/libluna/include/luna/Common.h

/**
 * @file Common.h
 * @author apio (cloudapio.eu)
 * @brief Common utility functions.
 *
 * @copyright Copyright (c) 2023, the Luna authors.
 *
 */

#pragma once

/**
 * @brief Divide a by b, rounding the quotient up to the next multiple of b.
 *
 * @tparam T The type of a and b.
 * @param a The dividend.
 * @param b The divisor.
 * @return constexpr T The result of the operation.
 */
template <typename T> inline constexpr T ceil_div(T a, T b)
{
    return (a + (b - 1)) / b;
}

/**
 * @brief Return the minimum value out of a set of arguments.
 *
 * @tparam T The type of the arguments.
 * @param a The first value of the set of arguments.
 * @param args The rest of the set of arguments.
 * @return constexpr T The minimum value.
 */
template <typename T, class... Args> inline constexpr T min(T a, Args... args)
{
    if constexpr (sizeof...(args) == 0) return a;
    else
    {
        T b = min(args...);
        return a > b ? b : a;
    }
}

/**
 * @brief Return the maximum value out of a set of arguments.
 *
 * @tparam T The type of the arguments.
 * @param a The first value of the set of arguments.
 * @param args The rest of the set of arguments.
 * @return constexpr T The maximum value.
 */
template <typename T, class... Args> inline constexpr T max(T a, Args... args)
{
    if constexpr (sizeof...(args) == 0) return a;
    else
    {
        T b = max(args...);
        return a > b ? a : b;
    }
}