Function IsValidJsonNumber

src/common/jsonapi.c:114–144

* Utility function to check if a string is a valid JSON number. * * str is of length len, and need not be null-terminated. */

 * str is of length len, and need not be null-terminated.
 */
bool
IsValidJsonNumber(const char *str, int len)
{
	bool		numeric_error;
	int			total_len;
	JsonLexContext dummy_lex;

	if (len <= 0)
		return false;

	/*
	 * json_lex_number expects a leading  '-' to have been eaten already.
	 *
	 * having to cast away the constness of str is ugly, but there's not much
	 * easy alternative.
	 */
	if (*str == '-')
	{
		dummy_lex.input = unconstify(char *, str) + 1;
		dummy_lex.input_length = len - 1;
	}
	else
	{
		dummy_lex.input = unconstify(char *, str);
		dummy_lex.input_length = len;
	}

	json_lex_number(&dummy_lex, dummy_lex.input, &numeric_error, &total_len);

	return (!numeric_error) && (total_len == dummy_lex.input_length);
}

/*
 * makeJsonLexContextCstringLen