// Copyright (c) 2020-2022 The Bitcoin Core developers

// Distributed under the MIT software license, see the accompanying

// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <test/fuzz/FuzzedDataProvider.h>

#include <test/fuzz/fuzz.h>

#include <test/fuzz/util.h>

#include <util/overflow.h>

#include <cstdint>

#include <string>

#include <vector>

namespace {

template <typename T>

void TestAdditionOverflow(FuzzedDataProvider& fuzzed_data_provider)

{

    const T i = fuzzed_data_provider.ConsumeIntegral<T>();

    const T j = fuzzed_data_provider.ConsumeIntegral<T>();

    const bool is_addition_overflow_custom = AdditionOverflow(i, j);

    const auto maybe_add{CheckedAdd(i, j)};

    const auto sat_add{SaturatingAdd(i, j)};

    assert(is_addition_overflow_custom == !maybe_add.has_value());

    assert(is_addition_overflow_custom == AdditionOverflow(j, i));

    assert(maybe_add == CheckedAdd(j, i));

    assert(sat_add == SaturatingAdd(j, i));

#ifndef _MSC_VER

    T result_builtin;

    const bool is_addition_overflow_builtin = __builtin_add_overflow(i, j, &result_builtin);

    assert(is_addition_overflow_custom == is_addition_overflow_builtin);

    if (!is_addition_overflow_custom) {

        assert(i + j == result_builtin);

    }

#endif

    if (is_addition_overflow_custom) {

        assert(sat_add == std::numeric_limits<T>::min() || sat_add == std::numeric_limits<T>::max());

    } else {

        const auto add{i + j};

        assert(add == maybe_add.value());

        assert(add == sat_add);

    }

}

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowIlEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowImEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowIiEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowIjEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowIsEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowItEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowIcEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowIhEEvR18FuzzedDataProvider

Unexecuted instantiation: addition_overflow.cpp:_ZN12_GLOBAL__N_120TestAdditionOverflowIaEEvR18FuzzedDataProvider

} // namespace

FUZZ_TARGET(addition_overflow)

{

    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());

    TestAdditionOverflow<int64_t>(fuzzed_data_provider);

    TestAdditionOverflow<uint64_t>(fuzzed_data_provider);

    TestAdditionOverflow<int32_t>(fuzzed_data_provider);

    TestAdditionOverflow<uint32_t>(fuzzed_data_provider);

    TestAdditionOverflow<int16_t>(fuzzed_data_provider);

    TestAdditionOverflow<uint16_t>(fuzzed_data_provider);

    TestAdditionOverflow<char>(fuzzed_data_provider);

    TestAdditionOverflow<unsigned char>(fuzzed_data_provider);

    TestAdditionOverflow<signed char>(fuzzed_data_provider);

}