/* {{{ proto string nl2br(string str)
   Converts newlines to HTML line breaks */
PHP_FUNCTION(nl2br)
{
	/* in brief this inserts 
 before matched regexp \n\r?|\r\n? */
	zval	**zstr;
	char	*tmp, *str;
	int	new_length;
	char	*end, *target;
	int	repl_cnt = 0;

	if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &zstr) == FAILURE) {
		WRONG_PARAM_COUNT;
	}
	
	convert_to_string_ex(zstr);

	str = Z_STRVAL_PP(zstr);
	end = str + Z_STRLEN_PP(zstr);
	
	/* it is really faster to scan twice and allocate mem once insted scanning once
	   and constantly reallocing */
	while (str < end) {
		if (*str == '\r') {
			if (*(str+1) == '\n') {
				str++;
			}
			repl_cnt++;
		} else if (*str == '\n') {
			if (*(str+1) == '\r') {
				str++;
			}
			repl_cnt++;
		}
		
		str++;
	}
	
	if (repl_cnt == 0) {
		RETURN_STRINGL(Z_STRVAL_PP(zstr), Z_STRLEN_PP(zstr), 1);
	}

	if ((new_length = Z_STRLEN_PP(zstr) + repl_cnt * (sizeof("
") - 1)) < 0) {
		RETURN_FALSE;
	}
	
	tmp = target = emalloc(new_length + 1);

	str = Z_STRVAL_PP(zstr);

	while (str < end) {
		switch (*str) {
			case '\r':
			case '\n':
				*target++ = '<';
				*target++ = 'b';
				*target++ = 'r';
				*target++ = ' ';
				*target++ = '/';
				*target++ = '>';
				
				if ((*str == '\r' && *(str+1) == '\n') || (*str == '\n' && *(str+1) == '\r')) {
					*target++ = *str++;
				}
				/* lack of a break; is intentional */
			default:
				*target++ = *str;
		}
	
		str++;
	}
	
	*target = '\0';

	RETURN_STRINGL(tmp, new_length, 0);
}
/* }}} */