blob: 6c141800af61181aa45ef00f57cad555316c8f63 [file] [log] [blame]
// Copyright 2020 The Pigweed Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
#pragma once
#include <limits.h>
namespace std {
template <typename T>
struct numeric_limits {
static constexpr bool is_specialized = false;
};
// Only a few of the numeric_limits methods are implemented.
#define _PW_LIMITS_SPECIALIZATION( \
type, val_signed, val_int, min_value, max_value) \
template <> \
struct numeric_limits<type> { \
static constexpr bool is_specialized = true; \
\
static constexpr bool is_signed = (val_signed); \
static constexpr bool is_integer = (val_int); \
\
static constexpr type min() noexcept { return (min_value); } \
static constexpr type max() noexcept { return (max_value); } \
}
#define _PW_INTEGRAL_LIMIT(type, sname, uname) \
_PW_LIMITS_SPECIALIZATION( \
signed type, true, true, sname##_MIN, sname##_MAX); \
_PW_LIMITS_SPECIALIZATION(unsigned type, false, true, 0u, uname##_MAX)
_PW_LIMITS_SPECIALIZATION(bool, false, true, false, true);
_PW_LIMITS_SPECIALIZATION(char, char(-1) < char(0), true, CHAR_MIN, CHAR_MAX);
_PW_INTEGRAL_LIMIT(char, SCHAR, UCHAR);
_PW_INTEGRAL_LIMIT(short, SHRT, USHRT);
_PW_INTEGRAL_LIMIT(int, INT, UINT);
_PW_INTEGRAL_LIMIT(long, LONG, ULONG);
#ifndef LLONG_MIN
#define LLONG_MIN ((long long)(~0ull ^ (~0ull >> 1)))
#define LLONG_MAX ((long long)(~0ull >> 1))
#define ULLONG_MIN (0ull)
#define ULLONG_MAX (~0ull)
#endif // LLONG_MIN
_PW_INTEGRAL_LIMIT(long long, LLONG, ULLONG);
#undef _PW_LIMITS_SPECIALIZATION
#undef _PW_INTEGRAL_LIMIT
} // namespace std