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289eb786d4
This conversion is not very discoverable for the cases where an error is required without extra payload.
781 lines
27 KiB
Rust
781 lines
27 KiB
Rust
#[cfg(test)]
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mod tests;
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use crate::convert::From;
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use crate::error;
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use crate::fmt;
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use crate::result;
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use crate::sys;
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/// A specialized [`Result`] type for I/O operations.
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///
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/// This type is broadly used across [`std::io`] for any operation which may
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/// produce an error.
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///
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/// This typedef is generally used to avoid writing out [`io::Error`] directly and
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/// is otherwise a direct mapping to [`Result`].
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///
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/// While usual Rust style is to import types directly, aliases of [`Result`]
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/// often are not, to make it easier to distinguish between them. [`Result`] is
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/// generally assumed to be [`std::result::Result`][`Result`], and so users of this alias
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/// will generally use `io::Result` instead of shadowing the [prelude]'s import
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/// of [`std::result::Result`][`Result`].
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///
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/// [`std::io`]: crate::io
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/// [`io::Error`]: Error
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/// [`Result`]: crate::result::Result
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/// [prelude]: crate::prelude
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///
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/// # Examples
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///
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/// A convenience function that bubbles an `io::Result` to its caller:
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///
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/// ```
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/// use std::io;
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///
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/// fn get_string() -> io::Result<String> {
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/// let mut buffer = String::new();
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///
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/// io::stdin().read_line(&mut buffer)?;
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///
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/// Ok(buffer)
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/// }
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/// ```
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#[stable(feature = "rust1", since = "1.0.0")]
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pub type Result<T> = result::Result<T, Error>;
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/// The error type for I/O operations of the [`Read`], [`Write`], [`Seek`], and
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/// associated traits.
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///
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/// Errors mostly originate from the underlying OS, but custom instances of
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/// `Error` can be created with crafted error messages and a particular value of
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/// [`ErrorKind`].
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///
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/// [`Read`]: crate::io::Read
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/// [`Write`]: crate::io::Write
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/// [`Seek`]: crate::io::Seek
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#[stable(feature = "rust1", since = "1.0.0")]
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pub struct Error {
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repr: Repr,
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}
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#[stable(feature = "rust1", since = "1.0.0")]
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impl fmt::Debug for Error {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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fmt::Debug::fmt(&self.repr, f)
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}
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}
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enum Repr {
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Os(i32),
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Simple(ErrorKind),
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// &str is a fat pointer, but &&str is a thin pointer.
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SimpleMessage(ErrorKind, &'static &'static str),
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Custom(Box<Custom>),
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}
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#[derive(Debug)]
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struct Custom {
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kind: ErrorKind,
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error: Box<dyn error::Error + Send + Sync>,
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}
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/// A list specifying general categories of I/O error.
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///
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/// This list is intended to grow over time and it is not recommended to
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/// exhaustively match against it.
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///
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/// It is used with the [`io::Error`] type.
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///
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/// [`io::Error`]: Error
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#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
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#[stable(feature = "rust1", since = "1.0.0")]
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#[allow(deprecated)]
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#[non_exhaustive]
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pub enum ErrorKind {
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/// An entity was not found, often a file.
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#[stable(feature = "rust1", since = "1.0.0")]
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NotFound,
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/// The operation lacked the necessary privileges to complete.
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#[stable(feature = "rust1", since = "1.0.0")]
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PermissionDenied,
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/// The connection was refused by the remote server.
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#[stable(feature = "rust1", since = "1.0.0")]
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ConnectionRefused,
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/// The connection was reset by the remote server.
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#[stable(feature = "rust1", since = "1.0.0")]
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ConnectionReset,
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/// The remote host is not reachable.
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#[unstable(feature = "io_error_more", issue = "86442")]
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HostUnreachable,
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/// The network containing the remote host is not reachable.
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#[unstable(feature = "io_error_more", issue = "86442")]
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NetworkUnreachable,
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/// The connection was aborted (terminated) by the remote server.
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#[stable(feature = "rust1", since = "1.0.0")]
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ConnectionAborted,
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/// The network operation failed because it was not connected yet.
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#[stable(feature = "rust1", since = "1.0.0")]
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NotConnected,
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/// A socket address could not be bound because the address is already in
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/// use elsewhere.
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#[stable(feature = "rust1", since = "1.0.0")]
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AddrInUse,
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/// A nonexistent interface was requested or the requested address was not
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/// local.
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#[stable(feature = "rust1", since = "1.0.0")]
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AddrNotAvailable,
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/// The system's networking is down.
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#[unstable(feature = "io_error_more", issue = "86442")]
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NetworkDown,
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/// The operation failed because a pipe was closed.
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#[stable(feature = "rust1", since = "1.0.0")]
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BrokenPipe,
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/// An entity already exists, often a file.
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#[stable(feature = "rust1", since = "1.0.0")]
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AlreadyExists,
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/// The operation needs to block to complete, but the blocking operation was
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/// requested to not occur.
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#[stable(feature = "rust1", since = "1.0.0")]
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WouldBlock,
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/// A filesystem object is, unexpectedly, not a directory.
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///
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/// For example, a filesystem path was specified where one of the intermediate directory
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/// components was, in fact, a plain file.
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#[unstable(feature = "io_error_more", issue = "86442")]
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NotADirectory,
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/// The filesystem object is, unexpectedly, a directory.
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///
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/// A directory was specified when a non-directory was expected.
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#[unstable(feature = "io_error_more", issue = "86442")]
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IsADirectory,
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/// A non-empty directory was specified where an empty directory was expected.
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#[unstable(feature = "io_error_more", issue = "86442")]
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DirectoryNotEmpty,
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/// The filesystem or storage medium is read-only, but a write operation was attempted.
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#[unstable(feature = "io_error_more", issue = "86442")]
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ReadOnlyFilesystem,
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/// Loop in the filesystem or IO subsystem; often, too many levels of symbolic links.
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///
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/// There was a loop (or excessively long chain) resolving a filesystem object
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/// or file IO object.
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///
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/// On Unix this is usually the result of a symbolic link loop; or, of exceeding the
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/// system-specific limit on the depth of symlink traversal.
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#[unstable(feature = "io_error_more", issue = "86442")]
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FilesystemLoop,
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/// Stale network file handle.
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///
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/// With some network filesystems, notably NFS, an open file (or directory) can be invalidated
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/// by problems with the network or server.
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#[unstable(feature = "io_error_more", issue = "86442")]
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StaleNetworkFileHandle,
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/// A parameter was incorrect.
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#[stable(feature = "rust1", since = "1.0.0")]
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InvalidInput,
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/// Data not valid for the operation were encountered.
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///
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/// Unlike [`InvalidInput`], this typically means that the operation
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/// parameters were valid, however the error was caused by malformed
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/// input data.
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///
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/// For example, a function that reads a file into a string will error with
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/// `InvalidData` if the file's contents are not valid UTF-8.
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///
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/// [`InvalidInput`]: ErrorKind::InvalidInput
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#[stable(feature = "io_invalid_data", since = "1.2.0")]
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InvalidData,
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/// The I/O operation's timeout expired, causing it to be canceled.
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#[stable(feature = "rust1", since = "1.0.0")]
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TimedOut,
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/// An error returned when an operation could not be completed because a
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/// call to [`write`] returned [`Ok(0)`].
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///
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/// This typically means that an operation could only succeed if it wrote a
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/// particular number of bytes but only a smaller number of bytes could be
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/// written.
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///
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/// [`write`]: crate::io::Write::write
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/// [`Ok(0)`]: Ok
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#[stable(feature = "rust1", since = "1.0.0")]
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WriteZero,
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/// The underlying storage (typically, a filesystem) is full.
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///
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/// This does not include out of quota errors.
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#[unstable(feature = "io_error_more", issue = "86442")]
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StorageFull,
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/// Seek on unseekable file.
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///
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/// Seeking was attempted on an open file handle which is not suitable for seeking - for
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/// example, on Unix, a named pipe opened with `File::open`.
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#[unstable(feature = "io_error_more", issue = "86442")]
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NotSeekable,
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/// Filesystem quota was exceeded.
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#[unstable(feature = "io_error_more", issue = "86442")]
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FilesystemQuotaExceeded,
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/// File larger than allowed or supported.
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///
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/// This might arise from a hard limit of the underlying filesystem or file access API, or from
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/// an administratively imposed resource limitation. Simple disk full, and out of quota, have
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/// their own errors.
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#[unstable(feature = "io_error_more", issue = "86442")]
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FileTooLarge,
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/// Resource is busy.
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#[unstable(feature = "io_error_more", issue = "86442")]
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ResourceBusy,
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/// Executable file is busy.
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///
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/// An attempt was made to write to a file which is also in use as a running program. (Not all
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/// operating systems detect this situation.)
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#[unstable(feature = "io_error_more", issue = "86442")]
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ExecutableFileBusy,
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/// Deadlock (avoided).
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///
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/// A file locking operation would result in deadlock. This situation is typically detected, if
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/// at all, on a best-effort basis.
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#[unstable(feature = "io_error_more", issue = "86442")]
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Deadlock,
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/// Cross-device or cross-filesystem (hard) link or rename.
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#[unstable(feature = "io_error_more", issue = "86442")]
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CrossesDevices,
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/// Too many (hard) links to the same filesystem object.
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///
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/// The filesystem does not support making so many hardlinks to the same file.
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#[unstable(feature = "io_error_more", issue = "86442")]
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TooManyLinks,
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/// Filename too long.
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///
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/// The limit might be from the underlying filesystem or API, or an administratively imposed
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/// resource limit.
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#[unstable(feature = "io_error_more", issue = "86442")]
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FilenameTooLong,
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/// Program argument list too long.
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///
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/// When trying to run an external program, a system or process limit on the size of the
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/// arguments would have been exceeded.
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#[unstable(feature = "io_error_more", issue = "86442")]
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ArgumentListTooLong,
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/// This operation was interrupted.
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///
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/// Interrupted operations can typically be retried.
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#[stable(feature = "rust1", since = "1.0.0")]
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Interrupted,
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/// This operation is unsupported on this platform.
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///
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/// This means that the operation can never succeed.
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#[stable(feature = "unsupported_error", since = "1.53.0")]
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Unsupported,
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// ErrorKinds which are primarily categorisations for OS error
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// codes should be added above.
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//
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/// An error returned when an operation could not be completed because an
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/// "end of file" was reached prematurely.
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///
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/// This typically means that an operation could only succeed if it read a
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/// particular number of bytes but only a smaller number of bytes could be
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/// read.
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#[stable(feature = "read_exact", since = "1.6.0")]
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UnexpectedEof,
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/// An operation could not be completed, because it failed
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/// to allocate enough memory.
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#[stable(feature = "out_of_memory_error", since = "1.54.0")]
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OutOfMemory,
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// "Unusual" error kinds which do not correspond simply to (sets
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// of) OS error codes, should be added just above this comment.
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// `Other` and `Uncategorised` should remain at the end:
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//
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/// A custom error that does not fall under any other I/O error kind.
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///
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/// This can be used to construct your own [`Error`]s that do not match any
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/// [`ErrorKind`].
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///
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/// This [`ErrorKind`] is not used by the standard library.
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///
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/// Errors from the standard library that do not fall under any of the I/O
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/// error kinds cannot be `match`ed on, and will only match a wildcard (`_`) pattern.
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/// New [`ErrorKind`]s might be added in the future for some of those.
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#[stable(feature = "rust1", since = "1.0.0")]
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Other,
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/// Any I/O error from the standard library that's not part of this list.
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///
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/// Errors that are `Uncategorized` now may move to a different or a new
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/// [`ErrorKind`] variant in the future. It is not recommended to match
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/// an error against `Uncategorized`; use a wildcard match (`_`) instead.
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#[unstable(feature = "io_error_uncategorized", issue = "none")]
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#[doc(hidden)]
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Uncategorized,
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}
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impl ErrorKind {
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pub(crate) fn as_str(&self) -> &'static str {
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use ErrorKind::*;
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// Strictly alphabetical, please. (Sadly rustfmt cannot do this yet.)
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match *self {
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AddrInUse => "address in use",
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AddrNotAvailable => "address not available",
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AlreadyExists => "entity already exists",
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ArgumentListTooLong => "argument list too long",
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BrokenPipe => "broken pipe",
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ConnectionAborted => "connection aborted",
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ConnectionRefused => "connection refused",
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ConnectionReset => "connection reset",
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CrossesDevices => "cross-device link or rename",
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Deadlock => "deadlock",
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DirectoryNotEmpty => "directory not empty",
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ExecutableFileBusy => "executable file busy",
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FileTooLarge => "file too large",
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FilenameTooLong => "filename too long",
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FilesystemLoop => "filesystem loop or indirection limit (e.g. symlink loop)",
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FilesystemQuotaExceeded => "filesystem quota exceeded",
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HostUnreachable => "host unreachable",
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Interrupted => "operation interrupted",
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InvalidData => "invalid data",
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InvalidInput => "invalid input parameter",
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IsADirectory => "is a directory",
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NetworkDown => "network down",
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NetworkUnreachable => "network unreachable",
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NotADirectory => "not a directory",
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NotConnected => "not connected",
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NotFound => "entity not found",
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NotSeekable => "seek on unseekable file",
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Other => "other error",
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OutOfMemory => "out of memory",
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PermissionDenied => "permission denied",
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ReadOnlyFilesystem => "read-only filesystem or storage medium",
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ResourceBusy => "resource busy",
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StaleNetworkFileHandle => "stale network file handle",
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StorageFull => "no storage space",
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TimedOut => "timed out",
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TooManyLinks => "too many links",
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Uncategorized => "uncategorized error",
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UnexpectedEof => "unexpected end of file",
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Unsupported => "unsupported",
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WouldBlock => "operation would block",
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WriteZero => "write zero",
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}
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}
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}
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/// Intended for use for errors not exposed to the user, where allocating onto
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/// the heap (for normal construction via Error::new) is too costly.
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#[stable(feature = "io_error_from_errorkind", since = "1.14.0")]
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impl From<ErrorKind> for Error {
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/// Converts an [`ErrorKind`] into an [`Error`].
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///
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/// This conversion allocates a new error with a simple representation of error kind.
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///
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/// # Examples
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///
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/// ```
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/// use std::io::{Error, ErrorKind};
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///
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/// let not_found = ErrorKind::NotFound;
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/// let error = Error::from(not_found);
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/// assert_eq!("entity not found", format!("{}", error));
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/// ```
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#[inline]
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fn from(kind: ErrorKind) -> Error {
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Error { repr: Repr::Simple(kind) }
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}
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}
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impl Error {
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/// Creates a new I/O error from a known kind of error as well as an
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/// arbitrary error payload.
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///
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/// This function is used to generically create I/O errors which do not
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/// originate from the OS itself. The `error` argument is an arbitrary
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/// payload which will be contained in this [`Error`].
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///
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/// If no extra payload is required, use the `From` conversion from
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/// `ErrorKind`.
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///
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/// # Examples
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///
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/// ```
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/// use std::io::{Error, ErrorKind};
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///
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/// // errors can be created from strings
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/// let custom_error = Error::new(ErrorKind::Other, "oh no!");
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///
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/// // errors can also be created from other errors
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/// let custom_error2 = Error::new(ErrorKind::Interrupted, custom_error);
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///
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/// // creating an error without payload
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/// let eof_error = Error::from(ErrorKind::UnexpectedEof);
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/// ```
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#[stable(feature = "rust1", since = "1.0.0")]
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pub fn new<E>(kind: ErrorKind, error: E) -> Error
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where
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E: Into<Box<dyn error::Error + Send + Sync>>,
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{
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Self::_new(kind, error.into())
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}
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fn _new(kind: ErrorKind, error: Box<dyn error::Error + Send + Sync>) -> Error {
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Error { repr: Repr::Custom(Box::new(Custom { kind, error })) }
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}
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/// Creates a new I/O error from a known kind of error as well as a
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/// constant message.
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///
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/// This function does not allocate.
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///
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/// This function should maybe change to
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/// `new_const<const MSG: &'static str>(kind: ErrorKind)`
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/// in the future, when const generics allow that.
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#[inline]
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pub(crate) const fn new_const(kind: ErrorKind, message: &'static &'static str) -> Error {
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Self { repr: Repr::SimpleMessage(kind, message) }
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}
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/// Returns an error representing the last OS error which occurred.
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///
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/// This function reads the value of `errno` for the target platform (e.g.
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/// `GetLastError` on Windows) and will return a corresponding instance of
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/// [`Error`] for the error code.
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///
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/// # Examples
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///
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/// ```
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/// use std::io::Error;
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///
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/// println!("last OS error: {:?}", Error::last_os_error());
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/// ```
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#[stable(feature = "rust1", since = "1.0.0")]
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#[must_use]
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#[inline]
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pub fn last_os_error() -> Error {
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Error::from_raw_os_error(sys::os::errno() as i32)
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}
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/// Creates a new instance of an [`Error`] from a particular OS error code.
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///
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/// # Examples
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///
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/// On Linux:
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///
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/// ```
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/// # if cfg!(target_os = "linux") {
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/// use std::io;
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///
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/// let error = io::Error::from_raw_os_error(22);
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/// assert_eq!(error.kind(), io::ErrorKind::InvalidInput);
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/// # }
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/// ```
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///
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/// On Windows:
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///
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/// ```
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/// # if cfg!(windows) {
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|
/// use std::io;
|
|
///
|
|
/// let error = io::Error::from_raw_os_error(10022);
|
|
/// assert_eq!(error.kind(), io::ErrorKind::InvalidInput);
|
|
/// # }
|
|
/// ```
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
#[must_use]
|
|
#[inline]
|
|
pub fn from_raw_os_error(code: i32) -> Error {
|
|
Error { repr: Repr::Os(code) }
|
|
}
|
|
|
|
/// Returns the OS error that this error represents (if any).
|
|
///
|
|
/// If this [`Error`] was constructed via [`last_os_error`] or
|
|
/// [`from_raw_os_error`], then this function will return [`Some`], otherwise
|
|
/// it will return [`None`].
|
|
///
|
|
/// [`last_os_error`]: Error::last_os_error
|
|
/// [`from_raw_os_error`]: Error::from_raw_os_error
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// use std::io::{Error, ErrorKind};
|
|
///
|
|
/// fn print_os_error(err: &Error) {
|
|
/// if let Some(raw_os_err) = err.raw_os_error() {
|
|
/// println!("raw OS error: {:?}", raw_os_err);
|
|
/// } else {
|
|
/// println!("Not an OS error");
|
|
/// }
|
|
/// }
|
|
///
|
|
/// fn main() {
|
|
/// // Will print "raw OS error: ...".
|
|
/// print_os_error(&Error::last_os_error());
|
|
/// // Will print "Not an OS error".
|
|
/// print_os_error(&Error::new(ErrorKind::Other, "oh no!"));
|
|
/// }
|
|
/// ```
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
#[must_use]
|
|
#[inline]
|
|
pub fn raw_os_error(&self) -> Option<i32> {
|
|
match self.repr {
|
|
Repr::Os(i) => Some(i),
|
|
Repr::Custom(..) => None,
|
|
Repr::Simple(..) => None,
|
|
Repr::SimpleMessage(..) => None,
|
|
}
|
|
}
|
|
|
|
/// Returns a reference to the inner error wrapped by this error (if any).
|
|
///
|
|
/// If this [`Error`] was constructed via [`new`] then this function will
|
|
/// return [`Some`], otherwise it will return [`None`].
|
|
///
|
|
/// [`new`]: Error::new
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// use std::io::{Error, ErrorKind};
|
|
///
|
|
/// fn print_error(err: &Error) {
|
|
/// if let Some(inner_err) = err.get_ref() {
|
|
/// println!("Inner error: {:?}", inner_err);
|
|
/// } else {
|
|
/// println!("No inner error");
|
|
/// }
|
|
/// }
|
|
///
|
|
/// fn main() {
|
|
/// // Will print "No inner error".
|
|
/// print_error(&Error::last_os_error());
|
|
/// // Will print "Inner error: ...".
|
|
/// print_error(&Error::new(ErrorKind::Other, "oh no!"));
|
|
/// }
|
|
/// ```
|
|
#[stable(feature = "io_error_inner", since = "1.3.0")]
|
|
#[must_use]
|
|
#[inline]
|
|
pub fn get_ref(&self) -> Option<&(dyn error::Error + Send + Sync + 'static)> {
|
|
match self.repr {
|
|
Repr::Os(..) => None,
|
|
Repr::Simple(..) => None,
|
|
Repr::SimpleMessage(..) => None,
|
|
Repr::Custom(ref c) => Some(&*c.error),
|
|
}
|
|
}
|
|
|
|
/// Returns a mutable reference to the inner error wrapped by this error
|
|
/// (if any).
|
|
///
|
|
/// If this [`Error`] was constructed via [`new`] then this function will
|
|
/// return [`Some`], otherwise it will return [`None`].
|
|
///
|
|
/// [`new`]: Error::new
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// use std::io::{Error, ErrorKind};
|
|
/// use std::{error, fmt};
|
|
/// use std::fmt::Display;
|
|
///
|
|
/// #[derive(Debug)]
|
|
/// struct MyError {
|
|
/// v: String,
|
|
/// }
|
|
///
|
|
/// impl MyError {
|
|
/// fn new() -> MyError {
|
|
/// MyError {
|
|
/// v: "oh no!".to_string()
|
|
/// }
|
|
/// }
|
|
///
|
|
/// fn change_message(&mut self, new_message: &str) {
|
|
/// self.v = new_message.to_string();
|
|
/// }
|
|
/// }
|
|
///
|
|
/// impl error::Error for MyError {}
|
|
///
|
|
/// impl Display for MyError {
|
|
/// fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
/// write!(f, "MyError: {}", &self.v)
|
|
/// }
|
|
/// }
|
|
///
|
|
/// fn change_error(mut err: Error) -> Error {
|
|
/// if let Some(inner_err) = err.get_mut() {
|
|
/// inner_err.downcast_mut::<MyError>().unwrap().change_message("I've been changed!");
|
|
/// }
|
|
/// err
|
|
/// }
|
|
///
|
|
/// fn print_error(err: &Error) {
|
|
/// if let Some(inner_err) = err.get_ref() {
|
|
/// println!("Inner error: {}", inner_err);
|
|
/// } else {
|
|
/// println!("No inner error");
|
|
/// }
|
|
/// }
|
|
///
|
|
/// fn main() {
|
|
/// // Will print "No inner error".
|
|
/// print_error(&change_error(Error::last_os_error()));
|
|
/// // Will print "Inner error: ...".
|
|
/// print_error(&change_error(Error::new(ErrorKind::Other, MyError::new())));
|
|
/// }
|
|
/// ```
|
|
#[stable(feature = "io_error_inner", since = "1.3.0")]
|
|
#[must_use]
|
|
#[inline]
|
|
pub fn get_mut(&mut self) -> Option<&mut (dyn error::Error + Send + Sync + 'static)> {
|
|
match self.repr {
|
|
Repr::Os(..) => None,
|
|
Repr::Simple(..) => None,
|
|
Repr::SimpleMessage(..) => None,
|
|
Repr::Custom(ref mut c) => Some(&mut *c.error),
|
|
}
|
|
}
|
|
|
|
/// Consumes the `Error`, returning its inner error (if any).
|
|
///
|
|
/// If this [`Error`] was constructed via [`new`] then this function will
|
|
/// return [`Some`], otherwise it will return [`None`].
|
|
///
|
|
/// [`new`]: Error::new
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// use std::io::{Error, ErrorKind};
|
|
///
|
|
/// fn print_error(err: Error) {
|
|
/// if let Some(inner_err) = err.into_inner() {
|
|
/// println!("Inner error: {}", inner_err);
|
|
/// } else {
|
|
/// println!("No inner error");
|
|
/// }
|
|
/// }
|
|
///
|
|
/// fn main() {
|
|
/// // Will print "No inner error".
|
|
/// print_error(Error::last_os_error());
|
|
/// // Will print "Inner error: ...".
|
|
/// print_error(Error::new(ErrorKind::Other, "oh no!"));
|
|
/// }
|
|
/// ```
|
|
#[stable(feature = "io_error_inner", since = "1.3.0")]
|
|
#[must_use = "`self` will be dropped if the result is not used"]
|
|
#[inline]
|
|
pub fn into_inner(self) -> Option<Box<dyn error::Error + Send + Sync>> {
|
|
match self.repr {
|
|
Repr::Os(..) => None,
|
|
Repr::Simple(..) => None,
|
|
Repr::SimpleMessage(..) => None,
|
|
Repr::Custom(c) => Some(c.error),
|
|
}
|
|
}
|
|
|
|
/// Returns the corresponding [`ErrorKind`] for this error.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// use std::io::{Error, ErrorKind};
|
|
///
|
|
/// fn print_error(err: Error) {
|
|
/// println!("{:?}", err.kind());
|
|
/// }
|
|
///
|
|
/// fn main() {
|
|
/// // Will print "Uncategorized".
|
|
/// print_error(Error::last_os_error());
|
|
/// // Will print "AddrInUse".
|
|
/// print_error(Error::new(ErrorKind::AddrInUse, "oh no!"));
|
|
/// }
|
|
/// ```
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
#[must_use]
|
|
#[inline]
|
|
pub fn kind(&self) -> ErrorKind {
|
|
match self.repr {
|
|
Repr::Os(code) => sys::decode_error_kind(code),
|
|
Repr::Custom(ref c) => c.kind,
|
|
Repr::Simple(kind) => kind,
|
|
Repr::SimpleMessage(kind, _) => kind,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl fmt::Debug for Repr {
|
|
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
match *self {
|
|
Repr::Os(code) => fmt
|
|
.debug_struct("Os")
|
|
.field("code", &code)
|
|
.field("kind", &sys::decode_error_kind(code))
|
|
.field("message", &sys::os::error_string(code))
|
|
.finish(),
|
|
Repr::Custom(ref c) => fmt::Debug::fmt(&c, fmt),
|
|
Repr::Simple(kind) => fmt.debug_tuple("Kind").field(&kind).finish(),
|
|
Repr::SimpleMessage(kind, &message) => {
|
|
fmt.debug_struct("Error").field("kind", &kind).field("message", &message).finish()
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
impl fmt::Display for Error {
|
|
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
match self.repr {
|
|
Repr::Os(code) => {
|
|
let detail = sys::os::error_string(code);
|
|
write!(fmt, "{} (os error {})", detail, code)
|
|
}
|
|
Repr::Custom(ref c) => c.error.fmt(fmt),
|
|
Repr::Simple(kind) => write!(fmt, "{}", kind.as_str()),
|
|
Repr::SimpleMessage(_, &msg) => msg.fmt(fmt),
|
|
}
|
|
}
|
|
}
|
|
|
|
#[stable(feature = "rust1", since = "1.0.0")]
|
|
impl error::Error for Error {
|
|
#[allow(deprecated, deprecated_in_future)]
|
|
fn description(&self) -> &str {
|
|
match self.repr {
|
|
Repr::Os(..) | Repr::Simple(..) => self.kind().as_str(),
|
|
Repr::SimpleMessage(_, &msg) => msg,
|
|
Repr::Custom(ref c) => c.error.description(),
|
|
}
|
|
}
|
|
|
|
#[allow(deprecated)]
|
|
fn cause(&self) -> Option<&dyn error::Error> {
|
|
match self.repr {
|
|
Repr::Os(..) => None,
|
|
Repr::Simple(..) => None,
|
|
Repr::SimpleMessage(..) => None,
|
|
Repr::Custom(ref c) => c.error.cause(),
|
|
}
|
|
}
|
|
|
|
fn source(&self) -> Option<&(dyn error::Error + 'static)> {
|
|
match self.repr {
|
|
Repr::Os(..) => None,
|
|
Repr::Simple(..) => None,
|
|
Repr::SimpleMessage(..) => None,
|
|
Repr::Custom(ref c) => c.error.source(),
|
|
}
|
|
}
|
|
}
|
|
|
|
fn _assert_error_is_sync_send() {
|
|
fn _is_sync_send<T: Sync + Send>() {}
|
|
_is_sync_send::<Error>();
|
|
}
|