NSLDAPI_SAFE_STRLEN
len = NSLDAPI_SAFE_STRLEN(buf) + NSLDAPI_SAFE_STRLEN(tmpbase) +
NSLDAPI_SAFE_STRLEN(filter) + NSLDAPI_SAFE_STRLEN(defhost) +
NSLDAPI_SAFE_STRLEN(binddn);
len += NSLDAPI_SAFE_STRLEN(attrs[i]);