Address CR comments and add a test

    /// An unknown error

    UnknownError {

        /// The library reporting the error

        library: CString,

        library: String,

        /// The function reporting the error

        function: CString,

        function: String,

        /// The reason for the error

        reason: CString

        reason: String

    }

}

fn get_lib(err: c_ulong) -> CString {

    unsafe { CString::new(ffi::ERR_lib_error_string(err), false) }

fn get_lib(err: c_ulong) -> String {

    unsafe { CString::new(ffi::ERR_lib_error_string(err), false) }.to_string()

}

fn get_func(err: c_ulong) -> CString {

    unsafe { CString::new(ffi::ERR_func_error_string(err), false) }

fn get_func(err: c_ulong) -> String {

    unsafe { CString::new(ffi::ERR_func_error_string(err), false).to_string() }

}

fn get_reason(err: c_ulong) -> CString {

    unsafe { CString::new(ffi::ERR_reason_error_string(err), false) }

fn get_reason(err: c_ulong) -> String {

    unsafe { CString::new(ffi::ERR_reason_error_string(err), false).to_string() }

}

#[test]

fn test_uknown_error_should_have_correct_messages() {

    let err = 336032784;

    let library = get_lib(err);

    let function = get_func(err);

    let reason = get_reason(err);

    assert_eq!(library.as_slice(),"20");

    assert_eq!(function.as_slice(), "119");

    assert_eq!(reason.as_slice(), "1040");

}

impl SslError {