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/*
* Copyright (C) 2018-2019 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <unicode/utypes.h>
#include <wtf/ASCIICType.h>
namespace WTF {
inline bool isCharacterAllowedInBase(UChar c, int base)
{
if (c > 0x7F)
return false;
if (isASCIIDigit(c))
return c - '0' < base;
if (isASCIIAlpha(c)) {
if (base > 36)
base = 36;
return (c >= 'a' && c < 'a' + base - 10)
|| (c >= 'A' && c < 'A' + base - 10);
}
return false;
}
template<typename IntegralType, typename CharacterType>
inline IntegralType toIntegralType(const CharacterType* data, size_t length, bool* ok = nullptr, int base = 10)
{
static constexpr IntegralType integralMax = std::numeric_limits<IntegralType>::max();
static constexpr bool isSigned = std::numeric_limits<IntegralType>::is_signed;
const IntegralType maxMultiplier = integralMax / base;
IntegralType value = 0;
bool isOk = false;
bool isNegative = false;
if (!data)
goto bye;
// skip leading whitespace
while (length && isSpaceOrNewline(*data)) {
--length;
++data;
}
if (isSigned && length && *data == '-') {
--length;
++data;
isNegative = true;
} else if (length && *data == '+') {
--length;
++data;
}
if (!length || !isCharacterAllowedInBase(*data, base))
goto bye;
while (length && isCharacterAllowedInBase(*data, base)) {
--length;
IntegralType digitValue;
auto c = *data;
if (isASCIIDigit(c))
digitValue = c - '0';
else if (c >= 'a')
digitValue = c - 'a' + 10;
else
digitValue = c - 'A' + 10;
if (value > maxMultiplier || (value == maxMultiplier && digitValue > (integralMax % base) + isNegative))
goto bye;
value = base * value + digitValue;
++data;
}
#if COMPILER(MSVC)
#pragma warning(push, 0)
#pragma warning(disable:4146)
#endif
if (isNegative)
value = -value;
#if COMPILER(MSVC)
#pragma warning(pop)
#endif
// skip trailing space
while (length && isSpaceOrNewline(*data)) {
--length;
++data;
}
if (!length)
isOk = true;
bye:
if (ok)
*ok = isOk;
return isOk ? value : 0;
}
template<typename IntegralType, typename StringOrStringView>
inline IntegralType toIntegralType(const StringOrStringView& stringView, bool* ok = nullptr, int base = 10)
{
if (stringView.is8Bit())
return toIntegralType<IntegralType, LChar>(stringView.characters8(), stringView.length(), ok, base);
return toIntegralType<IntegralType, UChar>(stringView.characters16(), stringView.length(), ok, base);
}
}
using WTF::toIntegralType;