same_file/
unix.rs

1use std::fs::{File, OpenOptions};
2use std::hash::{Hash, Hasher};
3use std::io;
4use std::os::unix::fs::MetadataExt;
5use std::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd, RawFd};
6use std::path::Path;
7
8#[derive(Debug)]
9pub struct Handle {
10    file: Option<File>,
11    // If is_std is true, then we don't drop the corresponding File since it
12    // will close the handle.
13    is_std: bool,
14    dev: u64,
15    ino: u64,
16}
17
18impl Drop for Handle {
19    fn drop(&mut self) {
20        if self.is_std {
21            // unwrap() will not panic. Since we were able to open an
22            // std stream successfully, then `file` is guaranteed to be Some()
23            self.file.take().unwrap().into_raw_fd();
24        }
25    }
26}
27
28impl Eq for Handle {}
29
30impl PartialEq for Handle {
31    fn eq(&self, other: &Handle) -> bool {
32        (self.dev, self.ino) == (other.dev, other.ino)
33    }
34}
35
36impl AsRawFd for crate::Handle {
37    fn as_raw_fd(&self) -> RawFd {
38        // unwrap() will not panic. Since we were able to open the
39        // file successfully, then `file` is guaranteed to be Some()
40        self.0.file.as_ref().take().unwrap().as_raw_fd()
41    }
42}
43
44impl IntoRawFd for crate::Handle {
45    fn into_raw_fd(mut self) -> RawFd {
46        // unwrap() will not panic. Since we were able to open the
47        // file successfully, then `file` is guaranteed to be Some()
48        self.0.file.take().unwrap().into_raw_fd()
49    }
50}
51
52impl Hash for Handle {
53    fn hash<H: Hasher>(&self, state: &mut H) {
54        self.dev.hash(state);
55        self.ino.hash(state);
56    }
57}
58
59impl Handle {
60    pub fn from_path<P: AsRef<Path>>(p: P) -> io::Result<Handle> {
61        Handle::from_file(OpenOptions::new().read(true).open(p)?)
62    }
63
64    pub fn from_file(file: File) -> io::Result<Handle> {
65        let md = file.metadata()?;
66        Ok(Handle {
67            file: Some(file),
68            is_std: false,
69            dev: md.dev(),
70            ino: md.ino(),
71        })
72    }
73
74    pub fn from_std(file: File) -> io::Result<Handle> {
75        Handle::from_file(file).map(|mut h| {
76            h.is_std = true;
77            h
78        })
79    }
80
81    pub fn stdin() -> io::Result<Handle> {
82        Handle::from_std(unsafe { File::from_raw_fd(0) })
83    }
84
85    pub fn stdout() -> io::Result<Handle> {
86        Handle::from_std(unsafe { File::from_raw_fd(1) })
87    }
88
89    pub fn stderr() -> io::Result<Handle> {
90        Handle::from_std(unsafe { File::from_raw_fd(2) })
91    }
92
93    pub fn as_file(&self) -> &File {
94        // unwrap() will not panic. Since we were able to open the
95        // file successfully, then `file` is guaranteed to be Some()
96        self.file.as_ref().take().unwrap()
97    }
98
99    pub fn as_file_mut(&mut self) -> &mut File {
100        // unwrap() will not panic. Since we were able to open the
101        // file successfully, then `file` is guaranteed to be Some()
102        self.file.as_mut().take().unwrap()
103    }
104
105    pub fn dev(&self) -> u64 {
106        self.dev
107    }
108
109    pub fn ino(&self) -> u64 {
110        self.ino
111    }
112}
same_file/unix.rs

same_file/
unix.rs
