// Copyright (C) 2012-2019,2021 Internet Systems Consortium, Inc. ("ISC")

//

// This Source Code Form is subject to the terms of the Mozilla Public

// License, v. 2.0. If a copy of the MPL was not distributed with this

// file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef RANGE_UTIL_H

#define RANGE_UTIL_H 1

#include <stdlib.h>

#include <algorithm>

#include <functional>

// This header contains useful methods for conduction operations on

// a range of container elements. Currently the collection is limited,

// but it is expected to grow.

namespace isc {

namespace util {

/// @brief Checks if specified range in a container contains only zeros

///

/// @param begin beginning of the range

/// @param end end of the range

///

/// @return true if there are only zeroes, false otherwise

template <typename Iterator>

bool

isRangeZero(Iterator begin, Iterator end) {

    return (std::find_if(begin, end, [] (int x) { return (0 != x); })

            == end);

}

/// @brief Fill in specified range with a random data.

///

/// Make sure that random number generator is initialized

/// properly. Otherwise you will get the same pseudo-random sequence

/// after every start of your process.  Calling srand() is enough. This

/// method uses default rand(), which is usually a LCG pseudo-random

/// number generator, so it is not suitable for security

/// purposes. Please use cryptolink RNG if you are doing anything

/// related with security.

///

/// PRNG initialization is left out of this function on purpose. It may

/// be initialized to specific value on purpose, e.g. to repeat exactly

/// the same sequence in a test.

///

/// @param begin

/// @param end

template <typename Iterator>

void

fillRandom(Iterator begin, Iterator end) {

    for (Iterator x = begin; x != end; ++x) {

        *x = random();

    }

}

} // end of isc::util namespace

} // end of isc namespace

#endif  // RANGE_UTIL_H