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// Copyright 2024 Google LLC
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use crate::inode::InodeMode;
#[derive(Clone, Debug, Eq, PartialEq)]
pub(crate) struct FileTypeError;
/// File type.
#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum FileType {
/// Block device.
BlockDevice,
/// Character device.
CharacterDevice,
/// Directory.
Directory,
/// First-in first-out (FIFO) special file.
Fifo,
/// Regular file.
Regular,
/// Socket file.
Socket,
/// Symbolic link.
Symlink,
}
impl FileType {
pub(crate) fn from_dir_entry(val: u8) -> Result<Self, FileTypeError> {
match val {
1 => Ok(Self::Regular),
2 => Ok(Self::Directory),
3 => Ok(Self::CharacterDevice),
4 => Ok(Self::BlockDevice),
5 => Ok(Self::Fifo),
6 => Ok(Self::Socket),
7 => Ok(Self::Symlink),
_ => Err(FileTypeError),
}
}
/// Returns true if the file is a block device.
#[must_use]
pub fn is_block_dev(self) -> bool {
self == Self::BlockDevice
}
/// Returns true if the file is a character device.
#[must_use]
pub fn is_char_dev(self) -> bool {
self == Self::CharacterDevice
}
/// Returns true if the file is a directory.
#[must_use]
pub fn is_dir(self) -> bool {
self == Self::Directory
}
/// Returns true if the file is a first-in first-out (FIFO) special file.
#[must_use]
pub fn is_fifo(self) -> bool {
self == Self::Fifo
}
/// Returns true if the file is a regular file.
#[must_use]
pub fn is_regular_file(self) -> bool {
self == Self::Regular
}
/// Returns true if the file is a socket.
#[must_use]
pub fn is_socket(self) -> bool {
self == Self::Socket
}
/// Returns true if the file is a symlink.
#[must_use]
pub fn is_symlink(self) -> bool {
self == Self::Symlink
}
}
impl TryFrom<InodeMode> for FileType {
type Error = FileTypeError;
fn try_from(mode: InodeMode) -> Result<Self, Self::Error> {
// Mask out the lower bits.
let mode = InodeMode::from_bits_retain(mode.bits() & 0xf000);
if mode == InodeMode::S_IFIFO {
Ok(Self::Fifo)
} else if mode == InodeMode::S_IFCHR {
Ok(Self::CharacterDevice)
} else if mode == InodeMode::S_IFDIR {
Ok(Self::Directory)
} else if mode == InodeMode::S_IFBLK {
Ok(Self::BlockDevice)
} else if mode == InodeMode::S_IFREG {
Ok(Self::Regular)
} else if mode == InodeMode::S_IFLNK {
Ok(Self::Symlink)
} else if mode == InodeMode::S_IFSOCK {
Ok(Self::Socket)
} else {
Err(FileTypeError)
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_file_type() {
// Check each valid file type.
assert!(FileType::try_from(InodeMode::S_IFIFO).unwrap().is_fifo());
assert!(
FileType::try_from(InodeMode::S_IFCHR)
.unwrap()
.is_char_dev()
);
assert!(
FileType::try_from(InodeMode::S_IFBLK)
.unwrap()
.is_block_dev()
);
assert!(
FileType::try_from(InodeMode::S_IFREG)
.unwrap()
.is_regular_file()
);
assert!(FileType::try_from(InodeMode::S_IFLNK).unwrap().is_symlink());
assert!(FileType::try_from(InodeMode::S_IFSOCK).unwrap().is_socket());
// Check that other bits being set in the mode don't impact the
// file type.
assert!(
FileType::try_from(InodeMode::S_IFREG | InodeMode::S_IXOTH)
.unwrap()
.is_regular_file()
);
// Error, no file type set.
assert_eq!(
FileType::try_from(InodeMode::empty()).unwrap_err(),
FileTypeError
);
}
}