libmtp_rs/
error.rs

1//! This module contains information about possible errors, such as internal and `libmtp` errors.
2
3use libmtp_sys as ffi;
4use std::string::FromUtf8Error;
5use thiserror::Error as ErrorTrait;
6
7/// Enumeration of possible `libmtp` errors, check
8/// [`Error::MtpError`](enum.Error.html#variant.MtpError) for more information.
9#[derive(Debug, Clone, Copy)]
10pub enum MtpErrorKind {
11    General,
12    PtpLayer,
13    UsbLayer,
14    MemoryAllocation,
15    NoDeviceAttached,
16    StorageFull,
17    Connecting,
18    Cancelled,
19}
20
21impl MtpErrorKind {
22    pub(crate) fn from_error_number(error_code: ffi::LIBMTP_error_number_t) -> Option<Self> {
23        match error_code {
24            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_NONE => None,
25            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_GENERAL => Some(Self::General),
26            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_PTP_LAYER => Some(Self::PtpLayer),
27            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_USB_LAYER => Some(Self::UsbLayer),
28            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_MEMORY_ALLOCATION => {
29                Some(Self::MemoryAllocation)
30            }
31            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_NO_DEVICE_ATTACHED => {
32                Some(Self::NoDeviceAttached)
33            }
34            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_STORAGE_FULL => Some(Self::StorageFull),
35            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_CONNECTING => Some(Self::Connecting),
36            ffi::LIBMTP_error_number_t_LIBMTP_ERROR_CANCELLED => Some(Self::Cancelled),
37            _ => None,
38        }
39    }
40}
41
42/// Main Error type, containing a possible *unknown* error, an specific `libmtp` error
43/// and some other internal errors like invalid UTF-8 in string conversion.
44#[derive(Debug, Clone, ErrorTrait)]
45pub enum Error {
46    /// Unknown error, probably some `libmtp` undocumented error.
47    #[error("Unknown error (possibly a libmtp undocumented error)")]
48    Unknown,
49
50    /// Specific `libmtp` error, contains the kind of the error and extra information
51    /// about what went wrong.
52    #[error("Internal libmtp ({kind:?}): {text}")]
53    MtpError { kind: MtpErrorKind, text: String },
54
55    /// Internal error when converting strings with invalid UTF-8 encoding.
56    #[error("Utf8 error ({source})")]
57    Utf8Error { source: FromUtf8Error },
58}
59
60impl Default for Error {
61    fn default() -> Self {
62        Error::Unknown
63    }
64}
65
66impl Error {
67    pub(crate) unsafe fn from_latest_error(mut list: *const ffi::LIBMTP_error_t) -> Option<Self> {
68        if list.is_null() {
69            None
70        } else {
71            while !(*list).next.is_null() {
72                list = (*list).next;
73            }
74
75            let error_t = &*list;
76
77            let kind = MtpErrorKind::from_error_number(error_t.errornumber)?;
78            let u8vec = cstr_to_u8vec!(error_t.error_text);
79            let text = String::from_utf8_lossy(&u8vec).into_owned();
80
81            Some(Error::MtpError { kind, text })
82        }
83    }
84}
85
86impl From<FromUtf8Error> for Error {
87    fn from(source: FromUtf8Error) -> Self {
88        Error::Utf8Error { source }
89    }
90}