Merge branch 'utimensat' into 'master'

add utimensat

See merge request redox-os/relibc!1268

src/header/fcntl/redox.rs

@@ -30,7 +30,9 @@ pub const O_NDELAY: c_int = O_NONBLOCK;
 
 // Flags for capability based "at" functions
 pub const AT_FDCWD: c_int = -100;
+// fchmodat, fchownat, fstatat, utimensat
 pub const AT_SYMLINK_NOFOLLOW: c_int = 0x200;
+// unlinkat
 pub const AT_REMOVEDIR: c_int = 0x200;
 // Used by linkat()
 pub const AT_SYMLINK_FOLLOW: c_int = 0x2000;

src/platform/linux/mod.rs

@@ -304,12 +304,13 @@ impl Pal for Sys {
         .map(|n| n as u32)
     }
 
-    unsafe fn futimens(fd: c_int, times: *const timespec) -> Result<()> {
-        e_raw(unsafe { syscall!(UTIMENSAT, fd, ptr::null::<c_char>(), times, 0) }).map(|_| ())
-    }
-
-    unsafe fn utimens(path: CStr, times: *const timespec) -> Result<()> {
-        e_raw(unsafe { syscall!(UTIMENSAT, AT_FDCWD, path.as_ptr(), times, 0) }).map(|_| ())
+    unsafe fn utimensat(
+        dirfd: c_int,
+        path: CStr,
+        times: *const timespec,
+        flag: c_int,
+    ) -> Result<()> {
+        e_raw(unsafe { syscall!(UTIMENSAT, dirfd, path.as_ptr(), times, flag) }).map(|_| ())
     }
 
     fn getcwd(mut buf: Out<[u8]>) -> Result<()> {

src/platform/pal/mod.rs

@@ -149,10 +149,23 @@ pub trait Pal {
     unsafe fn futex_wake(addr: *mut u32, num: u32) -> Result<u32>;
 
     /// Platform implementation of [`futimens()`](crate::header::sys_stat::futimens) from [`sys/stat.h`](crate::header::sys_stat).
-    unsafe fn futimens(fd: c_int, times: *const timespec) -> Result<()>;
+    unsafe fn futimens(fd: c_int, times: *const timespec) -> Result<()> {
+        unsafe { Self::utimensat(fd, c"".into(), times, AT_EMPTY_PATH) }
+    }
 
-    /// Platform implementation of `utimens()` (TODO) from [`sys/stat.h`](crate::header::sys_stat).
-    unsafe fn utimens(path: CStr, times: *const timespec) -> Result<()>;
+    /// Platform implementation of [`utimens()`](crate::header::unistd::utimens) (from [`sys/stat.h`](crate::header::sys_stat).
+    /// This is an extension of POSIX.
+    unsafe fn utimens(path: CStr, times: *const timespec) -> Result<()> {
+        unsafe { Self::utimensat(AT_FDCWD, path, times, 0) }
+    }
+
+    /// Platform implementation of [`utimensat()`](crate::header::unistd::utimensat) (from [`sys/stat.h`](crate::header::sys_stat).
+    unsafe fn utimensat(
+        dirfd: c_int,
+        path: CStr,
+        times: *const timespec,
+        flag: c_int,
+    ) -> Result<()>;
 
     /// Platform implementation of [`getcwd()`](crate::header::unistd::getcwd) from [`unistd.h`](crate::header::unistd).
     fn getcwd(buf: Out<[u8]>) -> Result<()>;

src/platform/redox/mod.rs

@@ -543,14 +543,28 @@ impl Pal for Sys {
         Ok(unsafe { redox_rt::sys::sys_futex_wake(addr, num) }?)
     }
 
-    unsafe fn futimens(fd: c_int, times: *const timespec) -> Result<()> {
-        (unsafe { libredox::futimens(fd as usize, times) })?;
-        Ok(())
-    }
+    unsafe fn utimensat(
+        dirfd: c_int,
+        path: CStr,
+        times: *const timespec,
+        flag: c_int,
+    ) -> Result<()> {
+        let mut path = path.to_str().map_err(|_| Errno(ENOENT))?;
+        if path.is_empty() {
+            if flag & AT_EMPTY_PATH == AT_EMPTY_PATH {
+                if dirfd == AT_FDCWD {
+                    path = ".";
+                } else {
+                    return Ok(unsafe { libredox::futimens(dirfd as usize, times) }?);
+                }
+            } else {
+                // If the path is empty but `AT_EMPTY_PATH` is **not** set, bail out.
+                return Err(Errno(ENOENT));
+            }
+        }
 
-    unsafe fn utimens(path: CStr, times: *const timespec) -> Result<()> {
-        let file = File::open(path, fcntl::O_PATH | fcntl::O_CLOEXEC)?;
-        unsafe { Self::futimens(*file, times) }
+        let file = openat2(dirfd, path, flag, fcntl::O_PATH | fcntl::O_CLOEXEC)?;
+        Ok(unsafe { libredox::futimens(*file as usize, times) }?)
     }
 
     fn getcwd(buf: Out<[u8]>) -> Result<()> {
@@ -1491,7 +1505,7 @@ impl Pal for Sys {
         // <sysname>\n e.g. "Redox"
         // <release>\n e.g. "0.9.0"
         // <machine>\n e.g. "x86_64"
-        // <version>\n e.g. "yyyy-mm-ddThh:mm:ssZ"
+        // <version>\n e.g. "<commit hash of kernel>
 
         // A future file format might add the domainname.