libcresult.rs

pub trait LibcResult<T> {
    /// returns None if the result is empty (-1 if an integer, Null if a pointer)
    /// and Some otherwise
    ///
    /// # Example
    /// if let Some(fd) = libc::creat(fd1, FILE_MODE).to_option() {
    ///     fd
    /// } else {
    ///     panic!("{}", io::Error::last_os_error());
    /// }
    fn to_option(&self) -> Option<T>;
}

impl LibcResult<c_int> for c_int {
    fn to_option(&self) -> Option<c_int> {
        if *self < 0 { None } else { Some(*self) }
    }
}

impl LibcResult<Sized> for Sized {
    fn to_option<T:Sized>(&self) -> Option<T> {
        if *self.is_null() { None } else { Some(*self) }
    }
}