1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143

use crate::{DirViewUtf8, ViewKind};
use cap_std::fs_utf8::{DirEntry, File, FileType, Metadata, OpenOptions};
#[cfg(not(windows))]
use rustix::fs::DirEntryExt;
use std::{fmt, io};

/// Entries returned by the `ReadDir` iterator.
///
/// This corresponds to [`std::fs::DirEntry`].
///
/// Unlike `std::fs::DirEntry`, this API has no `DirEntry::path`, because
/// absolute paths don't interoperate well with the capability model.
///
/// There is a `file_name` function, however there are also `open`,
/// `open_with`, `open_dir`, `remove_file`, and `remove_dir` functions for
/// opening or removing the entry directly, which can be more efficient and
/// convenient.
///
/// There is no `from_std` method, as `std::fs::DirEntry` doesn't provide a
/// way to construct a `DirEntry` without opening directories by ambient paths.
pub struct DirEntryViewUtf8 {
    pub(crate) entry: DirEntry,
    pub(crate) view_kind: ViewKind,
}

impl DirEntryViewUtf8 {
    /// Open the file for reading.
    #[inline]
    pub fn open(&self) -> io::Result<File> {
        self.entry.open()
    }

    /// Open the file with the given options.
    #[inline]
    pub fn open_with(&self, options: &OpenOptions) -> io::Result<File> {
        // Override any flag that allows writing.
        let mut options = options.clone();
        match self.view_kind {
            ViewKind::Full => {}
            ViewKind::Readonly => {
                // Override any flag that allows writing.
                options.append(false);
                options.truncate(false);
                options.write(false);
                options.create(false);
                options.create_new(false);
            }
        }
        self.entry.open_with(&options)
    }

    /// Open the entry as a directory.
    #[inline]
    pub fn open_dir(&self) -> io::Result<DirViewUtf8> {
        Ok(DirViewUtf8 {
            dir: self.entry.open_dir()?,
            view_kind: self.view_kind,
        })
    }

    /// Removes the file from its filesystem.
    #[inline]
    pub fn remove_file(&self) -> io::Result<()> {
        self.check_mutation()?;
        self.entry.remove_file()
    }

    /// Removes the directory from its filesystem.
    #[inline]
    pub fn remove_dir(&self) -> io::Result<()> {
        self.check_mutation()?;
        self.entry.remove_dir()
    }

    /// Returns the metadata for the file that this entry points at.
    ///
    /// This corresponds to [`std::fs::DirEntry::metadata`].
    #[inline]
    pub fn metadata(&self) -> io::Result<Metadata> {
        self.entry.metadata()
    }

    /// Returns the file type for the file that this entry points at.
    ///
    /// This corresponds to [`std::fs::DirEntry::file_type`].
    #[inline]
    pub fn file_type(&self) -> io::Result<FileType> {
        self.entry.file_type()
    }

    /// Returns the bare file name of this directory entry without any other
    /// leading path component.
    ///
    /// This corresponds to [`std::fs::DirEntry::file_name`].
    #[inline]
    pub fn file_name(&self) -> io::Result<String> {
        self.entry.file_name()
    }

    fn check_mutation(&self) -> io::Result<()> {
        match self.view_kind {
            ViewKind::Full => Ok(()),
            ViewKind::Readonly => Err(Self::readonly()),
        }
    }

    fn readonly() -> io::Error {
        io::Error::new(
            io::ErrorKind::PermissionDenied,
            "attempt to modify a directory tree through a read-only `DirViewUtf8`",
        )
    }
}

#[cfg(not(windows))]
impl DirEntryExt for DirEntryViewUtf8 {
    #[inline]
    fn ino(&self) -> u64 {
        self.entry.ino()
    }
}

#[cfg(windows)]
#[doc(hidden)]
impl cap_primitives::fs::_WindowsDirEntryExt for DirEntryViewUtf8 {
    #[inline]
    fn full_metadata(&self) -> io::Result<Metadata> {
        cap_primitives::fs::_WindowsDirEntryExt::full_metadata(&self.entry)
    }
}

impl fmt::Debug for DirEntryViewUtf8 {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        self.entry.fmt(f)
    }
}

#[cfg(feature = "cap-fs-ext")]
impl cap_fs_ext::DirEntryExt for DirEntryViewUtf8 {
    fn full_metadata(&self) -> io::Result<Metadata> {
        cap_fs_ext::DirEntryExt::full_metadata(&self.entry)
    }
}