rusty_modbus_frame/
error.rs

1//! Frame-layer error types.
2
3use rusty_modbus_codec::DecodeError;
4
5/// Errors that can occur during frame-level decode/encode.
6#[derive(Debug, thiserror::Error)]
7pub enum FrameError {
8    /// MBAP protocol identifier is not 0x0000.
9    #[error("invalid MBAP protocol identifier: {0:#06X}")]
10    InvalidProtocolId(u16),
11
12    /// MBAP length field exceeds maximum PDU size.
13    #[error("MBAP length overflow: {0}")]
14    LengthOverflow(u16),
15
16    /// MBAP length field cannot contain the Unit Identifier plus a function code.
17    #[error("invalid MBAP length: {declared} (minimum {minimum})")]
18    InvalidLength {
19        /// Declared MBAP length field value.
20        declared: u16,
21        /// Minimum valid MBAP length field value.
22        minimum: u16,
23    },
24
25    /// MBAP length field does not match the encoded payload size.
26    #[error("MBAP length mismatch: declared {declared}, actual {actual}")]
27    LengthMismatch {
28        /// Declared MBAP length field value.
29        declared: u16,
30        /// Actual length field value implied by the Unit Identifier and PDU bytes.
31        actual: u16,
32    },
33
34    /// PDU payload is too short to contain the function code.
35    #[error("invalid PDU length: {length} (minimum {minimum})")]
36    InvalidPduLength {
37        /// Actual PDU length in bytes.
38        length: usize,
39        /// Minimum valid PDU length in bytes.
40        minimum: usize,
41    },
42
43    /// PDU payload exceeds the Modbus maximum size.
44    #[error("PDU length overflow: {length} (maximum {maximum})")]
45    PduLengthOverflow {
46        /// Actual PDU length in bytes.
47        length: usize,
48        /// Maximum valid PDU length in bytes.
49        maximum: usize,
50    },
51
52    /// RTU CRC-16 mismatch.
53    #[error("CRC mismatch: expected {expected:#06X}, got {actual:#06X}")]
54    CrcMismatch {
55        /// Expected CRC value.
56        expected: u16,
57        /// Actual CRC value from the frame.
58        actual: u16,
59    },
60
61    /// Frame is truncated (not enough bytes).
62    #[error("frame truncated")]
63    Truncated,
64
65    /// Underlying I/O error.
66    #[error("I/O error: {0}")]
67    Io(#[from] std::io::Error),
68
69    /// PDU decode error.
70    #[error("decode error: {0}")]
71    Decode(#[from] DecodeError),
72}
rusty_modbus_frame/error.rs

rusty_modbus_frame/
error.rs
