IntegerToStringConversion.h [plain text]
#ifndef IntegerToStringConversion_h
#define IntegerToStringConversion_h
#include <wtf/text/LChar.h>
namespace WTF {
enum PositiveOrNegativeNumber { PositiveNumber, NegativeNumber };
template<typename> struct IntegerToStringConversionTrait;
template<typename T, typename UnsignedIntegerType, PositiveOrNegativeNumber NumberType, typename AdditionalArgumentType>
static typename IntegerToStringConversionTrait<T>::ReturnType numberToStringImpl(UnsignedIntegerType number, AdditionalArgumentType additionalArgument)
{
LChar buf[sizeof(UnsignedIntegerType) * 3 + 1];
LChar* end = std::end(buf);
LChar* p = end;
do {
*--p = static_cast<LChar>((number % 10) + '0');
number /= 10;
} while (number);
if (NumberType == NegativeNumber)
*--p = '-';
return IntegerToStringConversionTrait<T>::flush(p, static_cast<unsigned>(end - p), additionalArgument);
}
template<typename T, typename SignedIntegerType>
inline typename IntegerToStringConversionTrait<T>::ReturnType numberToStringSigned(SignedIntegerType number, typename IntegerToStringConversionTrait<T>::AdditionalArgumentType* additionalArgument = nullptr)
{
if (number < 0)
return numberToStringImpl<T, typename std::make_unsigned<SignedIntegerType>::type, NegativeNumber>(-number, additionalArgument);
return numberToStringImpl<T, typename std::make_unsigned<SignedIntegerType>::type, PositiveNumber>(number, additionalArgument);
}
template<typename T, typename UnsignedIntegerType>
inline typename IntegerToStringConversionTrait<T>::ReturnType numberToStringUnsigned(UnsignedIntegerType number, typename IntegerToStringConversionTrait<T>::AdditionalArgumentType* additionalArgument = nullptr)
{
return numberToStringImpl<T, UnsignedIntegerType, PositiveNumber>(number, additionalArgument);
}
template<typename CharacterType, typename UnsignedIntegerType, PositiveOrNegativeNumber NumberType>
static void writeNumberToBufferImpl(UnsignedIntegerType number, CharacterType* destination)
{
LChar buf[sizeof(UnsignedIntegerType) * 3 + 1];
LChar* end = std::end(buf);
LChar* p = end;
do {
*--p = static_cast<LChar>((number % 10) + '0');
number /= 10;
} while (number);
if (NumberType == NegativeNumber)
*--p = '-';
while (p < end)
*destination++ = static_cast<CharacterType>(*p++);
}
template<typename CharacterType, typename SignedIntegerType>
inline void writeNumberToBufferSigned(SignedIntegerType number, CharacterType* destination)
{
if (number < 0)
return writeNumberToBufferImpl<CharacterType, typename std::make_unsigned<SignedIntegerType>::type, NegativeNumber>(-number, destination);
return writeNumberToBufferImpl<CharacterType, typename std::make_unsigned<SignedIntegerType>::type, PositiveNumber>(number, destination);
}
template<typename CharacterType, typename UnsignedIntegerType>
inline void writeNumberToBufferUnsigned(UnsignedIntegerType number, CharacterType* destination)
{
return writeNumberToBufferImpl<CharacterType, UnsignedIntegerType, PositiveNumber>(number, destination);
}
template<typename UnsignedIntegerType, PositiveOrNegativeNumber NumberType>
static unsigned lengthOfNumberAsStringImpl(UnsignedIntegerType number)
{
unsigned length = 0;
do {
++length;
number /= 10;
} while (number);
if (NumberType == NegativeNumber)
++length;
return length;
}
template<typename SignedIntegerType>
inline unsigned lengthOfNumberAsStringSigned(SignedIntegerType number)
{
if (number < 0)
return lengthOfNumberAsStringImpl<typename std::make_unsigned<SignedIntegerType>::type, NegativeNumber>(-number);
return lengthOfNumberAsStringImpl<typename std::make_unsigned<SignedIntegerType>::type, PositiveNumber>(number);
}
template<typename UnsignedIntegerType>
inline unsigned lengthOfNumberAsStringUnsigned(UnsignedIntegerType number)
{
return lengthOfNumberAsStringImpl<UnsignedIntegerType, PositiveNumber>(number);
}
}
#endif // IntegerToStringConversion_h