X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=library%2Fstd%2Fsrc%2Ffs.rs;h=c8e131b6ee14c32f7c0e6ee7579467ba276f8b28;hb=1cff5642037b83ce1239a624bbe617a9aa0d59b1;hp=d799776548a65b9d3e069c687d8ab143857d7a7c;hpb=db8086eb6056f022d3bb719f777307e9daa3f8d8;p=rust.git

diff --git a/library/std/src/fs.rs b/library/std/src/fs.rs
index d799776548a..c8e131b6ee1 100644
--- a/library/std/src/fs.rs
+++ b/library/std/src/fs.rs
@@ -184,6 +184,11 @@ pub struct File {
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct OpenOptions(fs_imp::OpenOptions);
 
+/// Representation of the various timestamps on a file.
+#[derive(Copy, Clone, Debug, Default)]
+#[unstable(feature = "file_set_times", issue = "98245")]
+pub struct FileTimes(fs_imp::FileTimes);
+
 /// Representation of the various permissions on a file.
 ///
 /// This module only currently provides one bit of information,
@@ -596,6 +601,58 @@ pub fn try_clone(&self) -> io::Result<File> {
     pub fn set_permissions(&self, perm: Permissions) -> io::Result<()> {
         self.inner.set_permissions(perm.0)
     }
+
+    /// Changes the timestamps of the underlying file.
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// This function currently corresponds to the `futimens` function on Unix (falling back to
+    /// `futimes` on macOS before 10.13) and the `SetFileTime` function on Windows. Note that this
+    /// [may change in the future][changes].
+    ///
+    /// [changes]: io#platform-specific-behavior
+    ///
+    /// # Errors
+    ///
+    /// This function will return an error if the user lacks permission to change timestamps on the
+    /// underlying file. It may also return an error in other os-specific unspecified cases.
+    ///
+    /// This function may return an error if the operating system lacks support to change one or
+    /// more of the timestamps set in the `FileTimes` structure.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// #![feature(file_set_times)]
+    ///
+    /// fn main() -> std::io::Result<()> {
+    ///     use std::fs::{self, File, FileTimes};
+    ///
+    ///     let src = fs::metadata("src")?;
+    ///     let dest = File::options().write(true).open("dest")?;
+    ///     let times = FileTimes::new()
+    ///         .set_accessed(src.accessed()?)
+    ///         .set_modified(src.modified()?);
+    ///     dest.set_times(times)?;
+    ///     Ok(())
+    /// }
+    /// ```
+    #[unstable(feature = "file_set_times", issue = "98245")]
+    #[doc(alias = "futimens")]
+    #[doc(alias = "futimes")]
+    #[doc(alias = "SetFileTime")]
+    pub fn set_times(&self, times: FileTimes) -> io::Result<()> {
+        self.inner.set_times(times.0)
+    }
+
+    /// Changes the modification time of the underlying file.
+    ///
+    /// This is an alias for `set_times(FileTimes::new().set_modified(time))`.
+    #[unstable(feature = "file_set_times", issue = "98245")]
+    #[inline]
+    pub fn set_modified(&self, time: SystemTime) -> io::Result<()> {
+        self.set_times(FileTimes::new().set_modified(time))
+    }
 }
 
 // In addition to the `impl`s here, `File` also has `impl`s for
@@ -1252,6 +1309,30 @@ fn from_inner(attr: fs_imp::FileAttr) -> Metadata {
     }
 }
 
+impl FileTimes {
+    /// Create a new `FileTimes` with no times set.
+    ///
+    /// Using the resulting `FileTimes` in [`File::set_times`] will not modify any timestamps.
+    #[unstable(feature = "file_set_times", issue = "98245")]
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Set the last access time of a file.
+    #[unstable(feature = "file_set_times", issue = "98245")]
+    pub fn set_accessed(mut self, t: SystemTime) -> Self {
+        self.0.set_accessed(t.into_inner());
+        self
+    }
+
+    /// Set the last modified time of a file.
+    #[unstable(feature = "file_set_times", issue = "98245")]
+    pub fn set_modified(mut self, t: SystemTime) -> Self {
+        self.0.set_modified(t.into_inner());
+        self
+    }
+}
+
 impl Permissions {
     /// Returns `true` if these permissions describe a readonly (unwritable) file.
     ///