Function xpath_string convert_number_to_string

lib/pugixml/src/pugixml.cpp:8297–8362

#endif

	PUGI__FN xpath_string convert_number_to_string(double value, xpath_allocator* alloc)
	{
		// try special number conversion
		const char_t* special = convert_number_to_string_special(value);
		if (special) return xpath_string::from_const(special);

		// get mantissa + exponent form
		char mantissa_buffer[32];

		char* mantissa;
		int exponent;
		convert_number_to_mantissa_exponent(value, mantissa_buffer, &mantissa, &exponent);

		// allocate a buffer of suitable length for the number
		size_t result_size = strlen(mantissa_buffer) + (exponent > 0 ? exponent : -exponent) + 4;
		char_t* result = static_cast<char_t*>(alloc->allocate(sizeof(char_t) * result_size));
		if (!result) return xpath_string();

		// make the number!
		char_t* s = result;

		// sign
		if (value < 0) *s++ = '-';

		// integer part
		if (exponent <= 0)
		{
			*s++ = '0';
		}
		else
		{
			while (exponent > 0)
			{
				assert(*mantissa == 0 || static_cast<unsigned int>(*mantissa - '0') <= 9);
				*s++ = *mantissa ? *mantissa++ : '0';
				exponent--;
			}
		}

		// fractional part
		if (*mantissa)
		{
			// decimal point
			*s++ = '.';

			// extra zeroes from negative exponent
			while (exponent < 0)
			{
				*s++ = '0';
				exponent++;
			}

			// extra mantissa digits
			while (*mantissa)
			{
				assert(static_cast<unsigned int>(*mantissa - '0') <= 9);
				*s++ = *mantissa++;
			}