std/os/windows/
fs.rs

1//! Windows-specific extensions to primitives in the [`std::fs`] module.
2//!
3//! [`std::fs`]: crate::fs
4
5#![stable(feature = "rust1", since = "1.0.0")]
6
7use crate::fs::{self, Metadata, OpenOptions};
8use crate::io::BorrowedCursor;
9use crate::path::Path;
10use crate::sealed::Sealed;
11use crate::sys::{AsInner, AsInnerMut, IntoInner};
12use crate::time::SystemTime;
13use crate::{io, sys};
14
15/// Windows-specific extensions to [`fs::File`].
16#[stable(feature = "file_offset", since = "1.15.0")]
17pub trait FileExt {
18    /// Seeks to a given position and reads a number of bytes.
19    ///
20    /// Returns the number of bytes read.
21    ///
22    /// The offset is relative to the start of the file and thus independent
23    /// from the current cursor. The current cursor **is** affected by this
24    /// function, it is set to the end of the read.
25    ///
26    /// Reading beyond the end of the file will always return with a length of
27    /// 0\.
28    ///
29    /// Note that similar to `File::read`, it is not an error to return with a
30    /// short read. When returning from such a short read, the file pointer is
31    /// still updated.
32    ///
33    /// # Examples
34    ///
35    /// ```no_run
36    /// use std::io;
37    /// use std::fs::File;
38    /// use std::os::windows::prelude::*;
39    ///
40    /// fn main() -> io::Result<()> {
41    ///     let mut file = File::open("foo.txt")?;
42    ///     let mut buffer = [0; 10];
43    ///
44    ///     // Read 10 bytes, starting 72 bytes from the
45    ///     // start of the file.
46    ///     file.seek_read(&mut buffer[..], 72)?;
47    ///     Ok(())
48    /// }
49    /// ```
50    #[stable(feature = "file_offset", since = "1.15.0")]
51    fn seek_read(&self, buf: &mut [u8], offset: u64) -> io::Result<usize>;
52
53    /// Seeks to a given position and reads some bytes into the buffer.
54    ///
55    /// This is equivalent to the [`seek_read`](FileExt::seek_read) method, except that it is passed
56    /// a [`BorrowedCursor`] rather than `&mut [u8]` to allow use with uninitialized buffers. The
57    /// new data will be appended to any existing contents of `buf`.
58    ///
59    /// Reading beyond the end of the file will always succeed without reading any bytes.
60    ///
61    /// # Examples
62    ///
63    /// ```no_run
64    /// #![feature(core_io_borrowed_buf)]
65    /// #![feature(read_buf_at)]
66    ///
67    /// use std::io;
68    /// use std::io::BorrowedBuf;
69    /// use std::fs::File;
70    /// use std::mem::MaybeUninit;
71    /// use std::os::windows::prelude::*;
72    ///
73    /// fn main() -> io::Result<()> {
74    ///     let mut file = File::open("pi.txt")?;
75    ///
76    ///     // Read some bytes starting from offset 2
77    ///     let mut buf: [MaybeUninit<u8>; 10] = [MaybeUninit::uninit(); 10];
78    ///     let mut buf = BorrowedBuf::from(buf.as_mut_slice());
79    ///     file.seek_read_buf(buf.unfilled(), 2)?;
80    ///
81    ///     assert!(buf.filled().starts_with(b"1"));
82    ///
83    ///     Ok(())
84    /// }
85    /// ```
86    #[unstable(feature = "read_buf_at", issue = "140771")]
87    fn seek_read_buf(&self, buf: BorrowedCursor<'_>, offset: u64) -> io::Result<()> {
88        io::default_read_buf(|b| self.seek_read(b, offset), buf)
89    }
90
91    /// Seeks to a given position and writes a number of bytes.
92    ///
93    /// Returns the number of bytes written.
94    ///
95    /// The offset is relative to the start of the file and thus independent
96    /// from the current cursor. The current cursor **is** affected by this
97    /// function, it is set to the end of the write.
98    ///
99    /// When writing beyond the end of the file, the file is appropriately
100    /// extended and the intermediate bytes are set to zero.
101    ///
102    /// Note that similar to `File::write`, it is not an error to return a
103    /// short write. When returning from such a short write, the file pointer
104    /// is still updated.
105    ///
106    /// # Examples
107    ///
108    /// ```no_run
109    /// use std::fs::File;
110    /// use std::os::windows::prelude::*;
111    ///
112    /// fn main() -> std::io::Result<()> {
113    ///     let mut buffer = File::create("foo.txt")?;
114    ///
115    ///     // Write a byte string starting 72 bytes from
116    ///     // the start of the file.
117    ///     buffer.seek_write(b"some bytes", 72)?;
118    ///     Ok(())
119    /// }
120    /// ```
121    #[stable(feature = "file_offset", since = "1.15.0")]
122    fn seek_write(&self, buf: &[u8], offset: u64) -> io::Result<usize>;
123}
124
125#[stable(feature = "file_offset", since = "1.15.0")]
126impl FileExt for fs::File {
127    fn seek_read(&self, buf: &mut [u8], offset: u64) -> io::Result<usize> {
128        self.as_inner().read_at(buf, offset)
129    }
130
131    fn seek_read_buf(&self, buf: BorrowedCursor<'_>, offset: u64) -> io::Result<()> {
132        self.as_inner().read_buf_at(buf, offset)
133    }
134
135    fn seek_write(&self, buf: &[u8], offset: u64) -> io::Result<usize> {
136        self.as_inner().write_at(buf, offset)
137    }
138}
139
140/// Windows-specific extensions to [`fs::OpenOptions`].
141#[stable(feature = "open_options_ext", since = "1.10.0")]
142pub trait OpenOptionsExt {
143    /// Overrides the `dwDesiredAccess` argument to the call to [`CreateFile`]
144    /// with the specified value.
145    ///
146    /// This will override the `read`, `write`, and `append` flags on the
147    /// `OpenOptions` structure. This method provides fine-grained control over
148    /// the permissions to read, write and append data, attributes (like hidden
149    /// and system), and extended attributes.
150    ///
151    /// # Examples
152    ///
153    /// ```no_run
154    /// use std::fs::OpenOptions;
155    /// use std::os::windows::prelude::*;
156    ///
157    /// // Open without read and write permission, for example if you only need
158    /// // to call `stat` on the file
159    /// let file = OpenOptions::new().access_mode(0).open("foo.txt");
160    /// ```
161    ///
162    /// [`CreateFile`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea
163    #[stable(feature = "open_options_ext", since = "1.10.0")]
164    fn access_mode(&mut self, access: u32) -> &mut Self;
165
166    /// Overrides the `dwShareMode` argument to the call to [`CreateFile`] with
167    /// the specified value.
168    ///
169    /// By default `share_mode` is set to
170    /// `FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE`. This allows
171    /// other processes to read, write, and delete/rename the same file
172    /// while it is open. Removing any of the flags will prevent other
173    /// processes from performing the corresponding operation until the file
174    /// handle is closed.
175    ///
176    /// # Examples
177    ///
178    /// ```no_run
179    /// use std::fs::OpenOptions;
180    /// use std::os::windows::prelude::*;
181    ///
182    /// // Do not allow others to read or modify this file while we have it open
183    /// // for writing.
184    /// let file = OpenOptions::new()
185    ///     .write(true)
186    ///     .share_mode(0)
187    ///     .open("foo.txt");
188    /// ```
189    ///
190    /// [`CreateFile`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea
191    #[stable(feature = "open_options_ext", since = "1.10.0")]
192    fn share_mode(&mut self, val: u32) -> &mut Self;
193
194    /// Sets extra flags for the `dwFileFlags` argument to the call to
195    /// [`CreateFile2`] to the specified value (or combines it with
196    /// `attributes` and `security_qos_flags` to set the `dwFlagsAndAttributes`
197    /// for [`CreateFile`]).
198    ///
199    /// Custom flags can only set flags, not remove flags set by Rust's options.
200    /// This option overwrites any previously set custom flags.
201    ///
202    /// # Examples
203    ///
204    /// ```no_run
205    /// # #![allow(unexpected_cfgs)]
206    /// # #[cfg(for_demonstration_only)]
207    /// extern crate winapi;
208    /// # mod winapi { pub const FILE_FLAG_DELETE_ON_CLOSE: u32 = 0x04000000; }
209    ///
210    /// use std::fs::OpenOptions;
211    /// use std::os::windows::prelude::*;
212    ///
213    /// let file = OpenOptions::new()
214    ///     .create(true)
215    ///     .write(true)
216    ///     .custom_flags(winapi::FILE_FLAG_DELETE_ON_CLOSE)
217    ///     .open("foo.txt");
218    /// ```
219    ///
220    /// [`CreateFile`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea
221    /// [`CreateFile2`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfile2
222    #[stable(feature = "open_options_ext", since = "1.10.0")]
223    fn custom_flags(&mut self, flags: u32) -> &mut Self;
224
225    /// Sets the `dwFileAttributes` argument to the call to [`CreateFile2`] to
226    /// the specified value (or combines it with `custom_flags` and
227    /// `security_qos_flags` to set the `dwFlagsAndAttributes` for
228    /// [`CreateFile`]).
229    ///
230    /// If a _new_ file is created because it does not yet exist and
231    /// `.create(true)` or `.create_new(true)` are specified, the new file is
232    /// given the attributes declared with `.attributes()`.
233    ///
234    /// If an _existing_ file is opened with `.create(true).truncate(true)`, its
235    /// existing attributes are preserved and combined with the ones declared
236    /// with `.attributes()`.
237    ///
238    /// In all other cases the attributes get ignored.
239    ///
240    /// # Examples
241    ///
242    /// ```no_run
243    /// # #![allow(unexpected_cfgs)]
244    /// # #[cfg(for_demonstration_only)]
245    /// extern crate winapi;
246    /// # mod winapi { pub const FILE_ATTRIBUTE_HIDDEN: u32 = 2; }
247    ///
248    /// use std::fs::OpenOptions;
249    /// use std::os::windows::prelude::*;
250    ///
251    /// let file = OpenOptions::new()
252    ///     .write(true)
253    ///     .create(true)
254    ///     .attributes(winapi::FILE_ATTRIBUTE_HIDDEN)
255    ///     .open("foo.txt");
256    /// ```
257    ///
258    /// [`CreateFile`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea
259    /// [`CreateFile2`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfile2
260    #[stable(feature = "open_options_ext", since = "1.10.0")]
261    fn attributes(&mut self, val: u32) -> &mut Self;
262
263    /// Sets the `dwSecurityQosFlags` argument to the call to [`CreateFile2`] to
264    /// the specified value (or combines it with `custom_flags` and `attributes`
265    /// to set the `dwFlagsAndAttributes` for [`CreateFile`]).
266    ///
267    /// By default `security_qos_flags` is not set. It should be specified when
268    /// opening a named pipe, to control to which degree a server process can
269    /// act on behalf of a client process (security impersonation level).
270    ///
271    /// When `security_qos_flags` is not set, a malicious program can gain the
272    /// elevated privileges of a privileged Rust process when it allows opening
273    /// user-specified paths, by tricking it into opening a named pipe. So
274    /// arguably `security_qos_flags` should also be set when opening arbitrary
275    /// paths. However the bits can then conflict with other flags, specifically
276    /// `FILE_FLAG_OPEN_NO_RECALL`.
277    ///
278    /// For information about possible values, see [Impersonation Levels] on the
279    /// Windows Dev Center site. The `SECURITY_SQOS_PRESENT` flag is set
280    /// automatically when using this method.
281
282    /// # Examples
283    ///
284    /// ```no_run
285    /// # #![allow(unexpected_cfgs)]
286    /// # #[cfg(for_demonstration_only)]
287    /// extern crate winapi;
288    /// # mod winapi { pub const SECURITY_IDENTIFICATION: u32 = 0; }
289    /// use std::fs::OpenOptions;
290    /// use std::os::windows::prelude::*;
291    ///
292    /// let file = OpenOptions::new()
293    ///     .write(true)
294    ///     .create(true)
295    ///
296    ///     // Sets the flag value to `SecurityIdentification`.
297    ///     .security_qos_flags(winapi::SECURITY_IDENTIFICATION)
298    ///
299    ///     .open(r"\\.\pipe\MyPipe");
300    /// ```
301    ///
302    /// [`CreateFile`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea
303    /// [`CreateFile2`]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfile2
304    /// [Impersonation Levels]:
305    ///     https://docs.microsoft.com/en-us/windows/win32/api/winnt/ne-winnt-security_impersonation_level
306    #[stable(feature = "open_options_ext", since = "1.10.0")]
307    fn security_qos_flags(&mut self, flags: u32) -> &mut Self;
308
309    /// If set to `true`, prevent the "last access time" of the file from being changed.
310    ///
311    /// Default to `false`.
312    #[unstable(feature = "windows_freeze_file_times", issue = "149715")]
313    fn freeze_last_access_time(&mut self, freeze: bool) -> &mut Self;
314
315    /// If set to `true`, prevent the "last write time" of the file from being changed.
316    ///
317    /// Default to `false`.
318    #[unstable(feature = "windows_freeze_file_times", issue = "149715")]
319    fn freeze_last_write_time(&mut self, freeze: bool) -> &mut Self;
320}
321
322#[stable(feature = "open_options_ext", since = "1.10.0")]
323impl OpenOptionsExt for OpenOptions {
324    fn access_mode(&mut self, access: u32) -> &mut OpenOptions {
325        self.as_inner_mut().access_mode(access);
326        self
327    }
328
329    fn share_mode(&mut self, share: u32) -> &mut OpenOptions {
330        self.as_inner_mut().share_mode(share);
331        self
332    }
333
334    fn custom_flags(&mut self, flags: u32) -> &mut OpenOptions {
335        self.as_inner_mut().custom_flags(flags);
336        self
337    }
338
339    fn attributes(&mut self, attributes: u32) -> &mut OpenOptions {
340        self.as_inner_mut().attributes(attributes);
341        self
342    }
343
344    fn security_qos_flags(&mut self, flags: u32) -> &mut OpenOptions {
345        self.as_inner_mut().security_qos_flags(flags);
346        self
347    }
348
349    fn freeze_last_access_time(&mut self, freeze: bool) -> &mut Self {
350        self.as_inner_mut().freeze_last_access_time(freeze);
351        self
352    }
353
354    fn freeze_last_write_time(&mut self, freeze: bool) -> &mut Self {
355        self.as_inner_mut().freeze_last_write_time(freeze);
356        self
357    }
358}
359
360/// Windows-specific extensions to [`fs::Metadata`].
361///
362/// The data members that this trait exposes correspond to the members
363/// of the [`BY_HANDLE_FILE_INFORMATION`] structure.
364///
365/// [`BY_HANDLE_FILE_INFORMATION`]:
366///     https://docs.microsoft.com/windows/win32/api/fileapi/ns-fileapi-by_handle_file_information
367#[stable(feature = "metadata_ext", since = "1.1.0")]
368pub trait MetadataExt {
369    /// Returns the value of the `dwFileAttributes` field of this metadata.
370    ///
371    /// This field contains the file system attribute information for a file
372    /// or directory. For possible values and their descriptions, see
373    /// [File Attribute Constants] in the Windows Dev Center.
374    ///
375    /// # Examples
376    ///
377    /// ```no_run
378    /// use std::io;
379    /// use std::fs;
380    /// use std::os::windows::prelude::*;
381    ///
382    /// fn main() -> io::Result<()> {
383    ///     let metadata = fs::metadata("foo.txt")?;
384    ///     let attributes = metadata.file_attributes();
385    ///     Ok(())
386    /// }
387    /// ```
388    ///
389    /// [File Attribute Constants]:
390    ///     https://docs.microsoft.com/windows/win32/fileio/file-attribute-constants
391    #[stable(feature = "metadata_ext", since = "1.1.0")]
392    fn file_attributes(&self) -> u32;
393
394    /// Returns the value of the `ftCreationTime` field of this metadata.
395    ///
396    /// The returned 64-bit value is equivalent to a [`FILETIME`] struct,
397    /// which represents the number of 100-nanosecond intervals since
398    /// January 1, 1601 (UTC). The struct is automatically
399    /// converted to a `u64` value, as that is the recommended way
400    /// to use it.
401    ///
402    /// If the underlying filesystem does not support creation time, the
403    /// returned value is 0.
404    ///
405    /// # Examples
406    ///
407    /// ```no_run
408    /// use std::io;
409    /// use std::fs;
410    /// use std::os::windows::prelude::*;
411    ///
412    /// fn main() -> io::Result<()> {
413    ///     let metadata = fs::metadata("foo.txt")?;
414    ///     let creation_time = metadata.creation_time();
415    ///     Ok(())
416    /// }
417    /// ```
418    ///
419    /// [`FILETIME`]: https://docs.microsoft.com/windows/win32/api/minwinbase/ns-minwinbase-filetime
420    #[stable(feature = "metadata_ext", since = "1.1.0")]
421    fn creation_time(&self) -> u64;
422
423    /// Returns the value of the `ftLastAccessTime` field of this metadata.
424    ///
425    /// The returned 64-bit value is equivalent to a [`FILETIME`] struct,
426    /// which represents the number of 100-nanosecond intervals since
427    /// January 1, 1601 (UTC). The struct is automatically
428    /// converted to a `u64` value, as that is the recommended way
429    /// to use it.
430    ///
431    /// For a file, the value specifies the last time that a file was read
432    /// from or written to. For a directory, the value specifies when
433    /// the directory was created. For both files and directories, the
434    /// specified date is correct, but the time of day is always set to
435    /// midnight.
436    ///
437    /// If the underlying filesystem does not support last access time, the
438    /// returned value is 0.
439    ///
440    /// # Examples
441    ///
442    /// ```no_run
443    /// use std::io;
444    /// use std::fs;
445    /// use std::os::windows::prelude::*;
446    ///
447    /// fn main() -> io::Result<()> {
448    ///     let metadata = fs::metadata("foo.txt")?;
449    ///     let last_access_time = metadata.last_access_time();
450    ///     Ok(())
451    /// }
452    /// ```
453    ///
454    /// [`FILETIME`]: https://docs.microsoft.com/windows/win32/api/minwinbase/ns-minwinbase-filetime
455    #[stable(feature = "metadata_ext", since = "1.1.0")]
456    fn last_access_time(&self) -> u64;
457
458    /// Returns the value of the `ftLastWriteTime` field of this metadata.
459    ///
460    /// The returned 64-bit value is equivalent to a [`FILETIME`] struct,
461    /// which represents the number of 100-nanosecond intervals since
462    /// January 1, 1601 (UTC). The struct is automatically
463    /// converted to a `u64` value, as that is the recommended way
464    /// to use it.
465    ///
466    /// For a file, the value specifies the last time that a file was written
467    /// to. For a directory, the structure specifies when the directory was
468    /// created.
469    ///
470    /// If the underlying filesystem does not support the last write time,
471    /// the returned value is 0.
472    ///
473    /// # Examples
474    ///
475    /// ```no_run
476    /// use std::io;
477    /// use std::fs;
478    /// use std::os::windows::prelude::*;
479    ///
480    /// fn main() -> io::Result<()> {
481    ///     let metadata = fs::metadata("foo.txt")?;
482    ///     let last_write_time = metadata.last_write_time();
483    ///     Ok(())
484    /// }
485    /// ```
486    ///
487    /// [`FILETIME`]: https://docs.microsoft.com/windows/win32/api/minwinbase/ns-minwinbase-filetime
488    #[stable(feature = "metadata_ext", since = "1.1.0")]
489    fn last_write_time(&self) -> u64;
490
491    /// Returns the value of the `nFileSize` fields of this
492    /// metadata.
493    ///
494    /// The returned value does not have meaning for directories.
495    ///
496    /// # Examples
497    ///
498    /// ```no_run
499    /// use std::io;
500    /// use std::fs;
501    /// use std::os::windows::prelude::*;
502    ///
503    /// fn main() -> io::Result<()> {
504    ///     let metadata = fs::metadata("foo.txt")?;
505    ///     let file_size = metadata.file_size();
506    ///     Ok(())
507    /// }
508    /// ```
509    #[stable(feature = "metadata_ext", since = "1.1.0")]
510    fn file_size(&self) -> u64;
511
512    /// Returns the value of the `dwVolumeSerialNumber` field of this
513    /// metadata.
514    ///
515    /// This will return `None` if the `Metadata` instance was created from a
516    /// call to `DirEntry::metadata`. If this `Metadata` was created by using
517    /// `fs::metadata` or `File::metadata`, then this will return `Some`.
518    #[unstable(feature = "windows_by_handle", issue = "63010")]
519    fn volume_serial_number(&self) -> Option<u32>;
520
521    /// Returns the value of the `nNumberOfLinks` field of this
522    /// metadata.
523    ///
524    /// This will return `None` if the `Metadata` instance was created from a
525    /// call to `DirEntry::metadata`. If this `Metadata` was created by using
526    /// `fs::metadata` or `File::metadata`, then this will return `Some`.
527    #[unstable(feature = "windows_by_handle", issue = "63010")]
528    fn number_of_links(&self) -> Option<u32>;
529
530    /// Returns the value of the `nFileIndex` fields of this
531    /// metadata.
532    ///
533    /// This will return `None` if the `Metadata` instance was created from a
534    /// call to `DirEntry::metadata`. If this `Metadata` was created by using
535    /// `fs::metadata` or `File::metadata`, then this will return `Some`.
536    #[unstable(feature = "windows_by_handle", issue = "63010")]
537    fn file_index(&self) -> Option<u64>;
538
539    /// Returns the value of the `ChangeTime` fields of this metadata.
540    ///
541    /// `ChangeTime` is the last time file metadata was changed, such as
542    /// renames, attributes, etc.
543    ///
544    /// This will return `None` if `Metadata` instance was created from a call to
545    /// `DirEntry::metadata` or if the `target_vendor` is outside the current platform
546    /// support for this api.
547    #[unstable(feature = "windows_change_time", issue = "121478")]
548    fn change_time(&self) -> Option<u64>;
549}
550
551#[stable(feature = "metadata_ext", since = "1.1.0")]
552impl MetadataExt for Metadata {
553    fn file_attributes(&self) -> u32 {
554        self.as_inner().attrs()
555    }
556    fn creation_time(&self) -> u64 {
557        self.as_inner().created_u64()
558    }
559    fn last_access_time(&self) -> u64 {
560        self.as_inner().accessed_u64()
561    }
562    fn last_write_time(&self) -> u64 {
563        self.as_inner().modified_u64()
564    }
565    fn file_size(&self) -> u64 {
566        self.as_inner().size()
567    }
568    fn volume_serial_number(&self) -> Option<u32> {
569        self.as_inner().volume_serial_number()
570    }
571    fn number_of_links(&self) -> Option<u32> {
572        self.as_inner().number_of_links()
573    }
574    fn file_index(&self) -> Option<u64> {
575        self.as_inner().file_index()
576    }
577    fn change_time(&self) -> Option<u64> {
578        self.as_inner().changed_u64()
579    }
580}
581
582/// Windows-specific extensions to [`fs::FileType`].
583///
584/// On Windows, a symbolic link knows whether it is a file or directory.
585#[stable(feature = "windows_file_type_ext", since = "1.64.0")]
586pub trait FileTypeExt: Sealed {
587    /// Returns `true` if this file type is a symbolic link that is also a directory.
588    #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
589    fn is_symlink_dir(&self) -> bool;
590    /// Returns `true` if this file type is a symbolic link that is also a file.
591    #[stable(feature = "windows_file_type_ext", since = "1.64.0")]
592    fn is_symlink_file(&self) -> bool;
593}
594
595#[stable(feature = "windows_file_type_ext", since = "1.64.0")]
596impl Sealed for fs::FileType {}
597
598#[stable(feature = "windows_file_type_ext", since = "1.64.0")]
599impl FileTypeExt for fs::FileType {
600    fn is_symlink_dir(&self) -> bool {
601        self.as_inner().is_symlink_dir()
602    }
603    fn is_symlink_file(&self) -> bool {
604        self.as_inner().is_symlink_file()
605    }
606}
607
608/// Windows-specific extensions to [`fs::FileTimes`].
609#[stable(feature = "file_set_times", since = "1.75.0")]
610pub trait FileTimesExt: Sealed {
611    /// Set the creation time of a file.
612    #[stable(feature = "file_set_times", since = "1.75.0")]
613    fn set_created(self, t: SystemTime) -> Self;
614}
615
616#[stable(feature = "file_set_times", since = "1.75.0")]
617impl FileTimesExt for fs::FileTimes {
618    fn set_created(mut self, t: SystemTime) -> Self {
619        self.as_inner_mut().set_created(t.into_inner());
620        self
621    }
622}
623
624/// Creates a new symlink to a non-directory file on the filesystem.
625///
626/// The `link` path will be a file symbolic link pointing to the `original`
627/// path.
628///
629/// The `original` path should not be a directory or a symlink to a directory,
630/// otherwise the symlink will be broken. Use [`symlink_dir`] for directories.
631///
632/// This function currently corresponds to [`CreateSymbolicLinkW`][CreateSymbolicLinkW].
633/// Note that this [may change in the future][changes].
634///
635/// [CreateSymbolicLinkW]: https://docs.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-createsymboliclinkw
636/// [changes]: io#platform-specific-behavior
637///
638/// # Examples
639///
640/// ```no_run
641/// use std::os::windows::fs;
642///
643/// fn main() -> std::io::Result<()> {
644///     fs::symlink_file("a.txt", "b.txt")?;
645///     Ok(())
646/// }
647/// ```
648///
649/// # Limitations
650///
651/// Windows treats symlink creation as a [privileged action][symlink-security],
652/// therefore this function is likely to fail unless the user makes changes to
653/// their system to permit symlink creation. Users can try enabling Developer
654/// Mode, granting the `SeCreateSymbolicLinkPrivilege` privilege, or running
655/// the process as an administrator.
656///
657/// [symlink-security]: https://docs.microsoft.com/en-us/windows/security/threat-protection/security-policy-settings/create-symbolic-links
658#[stable(feature = "symlink", since = "1.1.0")]
659pub fn symlink_file<P: AsRef<Path>, Q: AsRef<Path>>(original: P, link: Q) -> io::Result<()> {
660    sys::fs::symlink_inner(original.as_ref(), link.as_ref(), false)
661}
662
663/// Creates a new symlink to a directory on the filesystem.
664///
665/// The `link` path will be a directory symbolic link pointing to the `original`
666/// path.
667///
668/// The `original` path must be a directory or a symlink to a directory,
669/// otherwise the symlink will be broken. Use [`symlink_file`] for other files.
670///
671/// This function currently corresponds to [`CreateSymbolicLinkW`][CreateSymbolicLinkW].
672/// Note that this [may change in the future][changes].
673///
674/// [CreateSymbolicLinkW]: https://docs.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-createsymboliclinkw
675/// [changes]: io#platform-specific-behavior
676///
677/// # Examples
678///
679/// ```no_run
680/// use std::os::windows::fs;
681///
682/// fn main() -> std::io::Result<()> {
683///     fs::symlink_dir("a", "b")?;
684///     Ok(())
685/// }
686/// ```
687///
688/// # Limitations
689///
690/// Windows treats symlink creation as a [privileged action][symlink-security],
691/// therefore this function is likely to fail unless the user makes changes to
692/// their system to permit symlink creation. Users can try enabling Developer
693/// Mode, granting the `SeCreateSymbolicLinkPrivilege` privilege, or running
694/// the process as an administrator.
695///
696/// [symlink-security]: https://docs.microsoft.com/en-us/windows/security/threat-protection/security-policy-settings/create-symbolic-links
697#[stable(feature = "symlink", since = "1.1.0")]
698pub fn symlink_dir<P: AsRef<Path>, Q: AsRef<Path>>(original: P, link: Q) -> io::Result<()> {
699    sys::fs::symlink_inner(original.as_ref(), link.as_ref(), true)
700}
701
702/// Creates a junction point.
703///
704/// The `link` path will be a directory junction pointing to the original path.
705/// If `link` is a relative path then it will be made absolute prior to creating the junction point.
706/// The `original` path must be a directory or a link to a directory, otherwise the junction point will be broken.
707///
708/// If either path is not a local file path then this will fail.
709#[unstable(feature = "junction_point", issue = "121709")]
710pub fn junction_point<P: AsRef<Path>, Q: AsRef<Path>>(original: P, link: Q) -> io::Result<()> {
711    sys::fs::junction_point(original.as_ref(), link.as_ref())
712}