Function float8in_internal_opt_error

src/backend/utils/adt/float.c:378–507

* float8in_internal_opt_error - guts of float8in() * * This is exposed for use by functions that want a reasonably * platform-independent way of inputting doubles. The behavior is * essentially like strtod + ereport on error, but note the following * differences: * 1. Both leading and trailing whitespace are skipped. * 2. If endptr_p is NULL, we throw error if there's trailing junk. * Oth

 * error.  This is helpful when caller need to handle errors by itself.
 */
double
float8in_internal_opt_error(char *num, char **endptr_p,
							const char *type_name, const char *orig_string,
							bool *have_error)
{
	double		val;
	char	   *endptr;

	if (have_error)
		*have_error = false;

	/* skip leading whitespace */
	while (*num != '\0' && isspace((unsigned char) *num))
		num++;

	/*
	 * Check for an empty-string input to begin with, to avoid the vagaries of
	 * strtod() on different platforms.
	 */
	if (*num == '\0')
		RETURN_ERROR(ereport(ERROR,
							 (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
							  errmsg("invalid input syntax for type %s: \"%s\"",
									 type_name, orig_string))),
					 have_error);

	errno = 0;
	val = strtod(num, &endptr);

	/* did we not see anything that looks like a double? */
	if (endptr == num || errno != 0)
	{
		int			save_errno = errno;

		/*
		 * C99 requires that strtod() accept NaN, [+-]Infinity, and [+-]Inf,
		 * but not all platforms support all of these (and some accept them
		 * but set ERANGE anyway...)  Therefore, we check for these inputs
		 * ourselves if strtod() fails.
		 *
		 * Note: C99 also requires hexadecimal input as well as some extended
		 * forms of NaN, but we consider these forms unportable and don't try
		 * to support them.  You can use 'em if your strtod() takes 'em.
		 */
		if (pg_strncasecmp(num, "NaN", 3) == 0)
		{
			val = get_float8_nan();
			endptr = num + 3;
		}
		else if (pg_strncasecmp(num, "Infinity", 8) == 0)
		{
			val = get_float8_infinity();
			endptr = num + 8;
		}
		else if (pg_strncasecmp(num, "+Infinity", 9) == 0)
		{
			val = get_float8_infinity();
			endptr = num + 9;