rusty-modbus-tcp 0.1.0

Modbus/TCP transport — split sink/stream traits and TCP implementation
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44

//! Transport error types.

use rusty_modbus_frame::FrameError;
use rusty_modbus_types::FunctionCode;

/// Errors that can occur during transport operations.
#[derive(Debug, thiserror::Error)]
pub enum TransportError {
    /// Underlying I/O error.
    #[error("I/O error: {0}")]
    Io(#[from] std::io::Error),

    /// Frame-level error (decode, encode, CRC, protocol ID).
    #[error("frame error: {0}")]
    Frame(#[from] FrameError),

    /// Operation timed out.
    #[error("operation timed out")]
    Timeout,

    /// Connection was closed by the remote peer.
    #[error("disconnected")]
    Disconnected,

    /// Connection denied by access control.
    #[error("access denied")]
    AccessDenied,

    /// TLS handshake failure (used by `modbus-tls`, defined here for `TransportError` unification).
    #[error("TLS handshake failed: {0}")]
    TlsHandshake(String),

    /// Authorization denied by server policy.
    #[error("authorization denied for role {role:?} on {function_code}")]
    AuthorizationDenied {
        /// Client role from certificate (if any).
        role: Option<String>,
        /// The function code that was denied.
        function_code: FunctionCode,
    },
}

/// TCP-specific error type (wraps `TransportError` for TCP context).
pub type TcpError = TransportError;