msft_typelib/
error.rs

1//! Error types for MSFT type library parsing.
2//!
3//! All errors are non-fatal data-validation failures.  Because the parser
4//! is zero-copy and does not allocate, I/O errors are the caller's
5//! responsibility (load the file, then pass `&[u8]` to
6//! [`TypeLib::parse`](crate::TypeLib::parse)).
7
8use std::fmt;
9
10/// Errors that can occur when parsing an MSFT type library.
11#[derive(Debug, Clone, PartialEq, Eq)]
12pub enum Error {
13    /// The input buffer is too short for the expected structure.
14    TooShort {
15        /// Minimum number of bytes required.
16        expected: usize,
17        /// Actual number of bytes available.
18        actual: usize,
19        /// Human-readable name of the structure being parsed.
20        context: &'static str,
21    },
22    /// The file does not start with the expected `"MSFT"` magic bytes.
23    BadMagic {
24        /// Expected magic value (`0x5446534D`).
25        expected: u32,
26        /// Actual value found at offset 0.
27        got: u32,
28    },
29    /// A TypeInfo index is outside the valid range `0..typeinfo_count`.
30    TypeInfoOutOfRange {
31        /// The requested index.
32        index: usize,
33        /// Total number of TypeInfo entries in this library.
34        count: usize,
35    },
36    /// A required field or offset could not be read from the binary data.
37    ///
38    /// This typically indicates a truncated or corrupt type library.
39    InvalidData {
40        /// Human-readable description of what went wrong.
41        context: &'static str,
42    },
43}
44
45impl fmt::Display for Error {
46    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
47        match self {
48            Error::TooShort {
49                expected,
50                actual,
51                context,
52            } => write!(
53                f,
54                "{context}: expected at least {expected} bytes, got {actual}"
55            ),
56            Error::BadMagic { expected, got } => {
57                write!(f, "bad magic: expected 0x{expected:08X}, got 0x{got:08X}")
58            }
59            Error::TypeInfoOutOfRange { index, count } => {
60                write!(f, "typeinfo index {index} out of range (count: {count})")
61            }
62            Error::InvalidData { context } => {
63                write!(f, "invalid data: {context}")
64            }
65        }
66    }
67}
68
69impl std::error::Error for Error {}
msft_typelib/error.rs

msft_typelib/
error.rs
