async_flow/io/
port.rs

1// This is free and unencumbered software released into the public domain.
2
3use super::PortState;
4use crate::PortDirection;
5use dogma::{MaybeLabeled, MaybeNamed};
6
7/// The common interface for ports, whether for input or output.
8pub trait Port<T: Send>: MaybeNamed + MaybeLabeled {
9    /// Closes this port without dropping it, returning immediately.
10    ///
11    /// If the port had an open connection, it will be disconnected.
12    /// If the port was already closed, no further action is taken.
13    /// There is no facility to reopen a port once it has been closed.
14    fn close(&mut self);
15
16    /// The dataflow direction of this port.
17    fn direction(&self) -> PortDirection;
18
19    /// The current state of this port.
20    fn state(&self) -> PortState;
21
22    /// Checks whether this port is an input port.
23    fn is_input(&self) -> bool {
24        self.direction().is_input()
25    }
26
27    /// Checks whether this port is an output port.
28    fn is_output(&self) -> bool {
29        self.direction().is_output()
30    }
31
32    /// Checks whether this port is currently unconnected.
33    fn is_unconnected(&self) -> bool {
34        self.state().is_unconnected()
35    }
36
37    /// Checks whether this port is currently connected.
38    fn is_connected(&self) -> bool {
39        self.state().is_connected()
40    }
41
42    /// Checks whether this port is currently disconnected.
43    fn is_disconnected(&self) -> bool {
44        self.state().is_disconnected()
45    }
46
47    /// Checks whether this port is currently closed.
48    fn is_closed(&self) -> bool {
49        self.state().is_closed()
50    }
51
52    /// Returns the remaining buffer capacity of the connection.
53    fn capacity(&self) -> Option<usize> {
54        None // unknown
55    }
56
57    /// Returns the maximum buffer capacity of the connection.
58    fn max_capacity(&self) -> Option<usize> {
59        None // unknown
60    }
61}
62
63impl<T: Send> core::fmt::Debug for &dyn Port<T> {
64    fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
65        f.debug_struct("Port")
66            .field("name", &self.name())
67            .field("state", &self.state())
68            .finish()
69    }
70}
async_flow/io/port.rs

async_flow/io/
port.rs
