Method close

kernel/src/rendezvous.rs:198–229

Close a Rendezvous. If a thread was waiting then it is returned and should be scheduled. An error SYSCALL_ERROR_CLOSED will be returned to the waiting thread.

(&mut self)

    /// If a thread was waiting then it is returned and should be scheduled.
    /// An error SYSCALL_ERROR_CLOSED will be returned to the waiting thread.
    pub fn close(&mut self) -> Option<Box<Thread>> {
        match &*self {
            Rendezvous::Empty => None,
            Rendezvous::Sending(_, _) => {
                // Cannot complete the message transfer
                if let Rendezvous::Sending(Some(snd_thread), message) = mem::replace(self, Rendezvous::Empty) {
                    snd_thread.return_error_message(syscalls::SYSCALL_ERROR_CLOSED, message);
                    Some(snd_thread)
                } else {
                    None
                }
            }
            Rendezvous::Receiving(_, _) => {
                // Will never receive a message
                if let Rendezvous::Receiving(rec_thread, _) = mem::replace(self, Rendezvous::Empty) {
                    rec_thread.return_error(syscalls::SYSCALL_ERROR_CLOSED);
                    Some(rec_thread)
                } else {
                    None
                }
            }
            Rendezvous::SendReceiving(_, _) => {
                // Cannot complete the message transfer
                if let Rendezvous::SendReceiving(snd_thread, message) = mem::replace(self, Rendezvous::Empty) {
                    snd_thread.return_error_message(syscalls::SYSCALL_ERROR_CLOSED, message);
                    Some(snd_thread)
                } else {
                    None
                }
            }
        }
    }
}