add support for futimens/utimensat

Author: Mic92

CHANGELOG.md

@@ -12,7 +12,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
   ([#582](https://github.com/nix-rust/nix/pull/582)
 - Added `nix::unistd::{openat, fstatat, readlink, readlinkat, rename, renameat, mknodat, unlinkat, mkdirat, link, linkat, symlink, symlinkat, access, faccessat}`
   ([#552](https://github.com/nix-rust/nix/pull/552), [#561](https://github.com/nix-rust/nix/pull/561))
-- Added `nix::stat::{chmod, fchmod, fchmodat}` ([#561](https://github.com/nix-rust/nix/pull/561))
+- Added `nix::stat::{chmod, fchmod, fchmodat, futimens, utimensat}` ([#561](https://github.com/nix-rust/nix/pull/561))
 - Added `nix::unistd::{chown, lchown, fchown, fchownat}` ([#561](https://github.com/nix-rust/nix/pull/561))
 - Added `nix::pty::{grantpt, posix_openpt, ptsname/ptsname_r, unlockpt}`
   ([#556](https://github.com/nix-rust/nix/pull/556)

src/sys/stat.rs

@@ -7,6 +7,8 @@ use libc::{self, mode_t};
 use std::mem;
 use std::os::unix::io::RawFd;
 
+pub use self::linux::*;
+
 mod ffi {
     use libc::{c_char, c_int, mode_t, dev_t};
     pub use libc::{stat, fstat, lstat};
@@ -179,3 +181,73 @@ pub fn fchmodat<P: ?Sized + NixPath>(dirfd: RawFd, pathname: &P, mode: Mode, fla
 
     Errno::result(res).map(drop)
 }
+
+#[cfg(target_os = "linux")]
+mod linux {
+    use {Errno, Result, NixPath};
+    use std::os::unix::io::RawFd;
+    use libc;
+    use fcntl::AtFlags;
+    use sys::time::TimeSpec;
+
+    /// A file timestamp.
+    pub enum UtimeSpec {
+        /// File timestamp is set to the current time.
+        Now,
+        /// The corresponding file timestamp is left unchanged.
+        Omit,
+        /// File timestamp is set to value
+        Time(TimeSpec)
+    }
+
+    impl <'a> From<&'a UtimeSpec> for libc::timespec {
+        fn from(time: &'a UtimeSpec) -> libc::timespec { 
+            match time {
+                &UtimeSpec::Now => libc::timespec {
+                    tv_sec: 0,
+                    tv_nsec: libc::UTIME_NOW,
+                },
+                &UtimeSpec::Omit => libc::timespec {
+                    tv_sec: 0,
+                    tv_nsec: libc::UTIME_OMIT,
+                },
+                &UtimeSpec::Time(spec) => *spec.as_ref()
+            }
+        }
+    }
+
+    /// Change file timestamps with nanosecond precision
+    /// (see [utimensat(2)](http://man7.org/linux/man-pages/man2/utimensat.2.html)).
+    pub fn utimensat<P: ?Sized + NixPath>(dirfd: RawFd,
+                                          pathname: &P,
+                                          atime: &UtimeSpec,
+                                          mtime: &UtimeSpec,
+                                          flags: AtFlags) -> Result<()> {
+        let time = [atime.into(), mtime.into()];
+        let res = try!(pathname.with_nix_path(|cstr| {
+            unsafe {
+                libc::utimensat(dirfd,
+                                cstr.as_ptr(),
+                                time.as_ptr() as *const libc::timespec,
+                                flags.bits())
+            }
+        }));
+
+        Errno::result(res).map(drop)
+    }
+
+    /// Change file timestamps with nanosecond precision
+    /// (see [futimens(2)](http://man7.org/linux/man-pages/man2/futimens.2.html)).
+    pub fn futimens(fd: RawFd,
+                    atime: &UtimeSpec,
+                    mtime: &UtimeSpec) -> Result<()> {
+        let time = [atime.into(), mtime.into()];
+        let res = unsafe {
+            libc::futimens(fd, time.as_ptr() as *const libc::timespec)
+        };
+    
+        Errno::result(res).map(drop)
+    }
+}
+#[cfg(not(target_os = "linux"))]
+mod linux { }

test/test_stat.rs

@@ -137,3 +137,20 @@ fn test_chmod() {
              fcntl::AtFlags::empty()).unwrap();
     assert_mode(&tempfile, 0o600);
 }
+
+#[test]
+#[cfg(target_os = "linux")]
+fn test_utime() {
+    use std::time::UNIX_EPOCH;
+    use nix::sys::time::{TimeSpec, TimeValLike};
+
+    let tempfile = NamedTempFile::new().unwrap();
+    utimensat(0, // is ignored, if pathname is absolute path
+              tempfile.path(),
+              &UtimeSpec::Time(TimeSpec::zero()),
+              &UtimeSpec::Time(TimeSpec::zero()),
+              fcntl::AtFlags::empty()).unwrap();
+    let mtime = tempfile.metadata().unwrap().modified().unwrap();
+
+    assert_eq!(mtime, UNIX_EPOCH);
+}