fs: introduce AT_ filehandle constants for name_to_handle_at(2)

Author: bertschingert

src/backend/libc/fs/types.rs

@@ -527,6 +527,34 @@ bitflags! {
     }
 }
 
+#[cfg(target_os = "linux")]
+bitflags! {
+    /// `AT_*` constants for use with [`name_to_handle_at`]
+    ///
+    /// [`name_to_handle_at`]: crate::fs::name_to_handle_at
+    #[repr(transparent)]
+    #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
+    pub struct HandleFlags: u32 {
+        /// `AT_HANDLE_FID`
+        const FID = linux_raw_sys::general::AT_HANDLE_FID;
+
+        /// `AT_HANDLE_MNT_ID_UNIQUE`
+        const MNT_ID_UNIQUE = linux_raw_sys::general::AT_HANDLE_MNT_ID_UNIQUE;
+
+        /// `AT_HANDLE_CONNECTABLE`
+        const CONNECTABLE = linux_raw_sys::general::AT_HANDLE_CONNECTABLE;
+
+        /// `AT_SYMLINK_FOLLOW`
+        const SYMLINK_FOLLOW = linux_raw_sys::general::AT_SYMLINK_FOLLOW;
+
+        /// `AT_EMPTY_PATH`
+        const EMPTY_PATH = linux_raw_sys::general::AT_EMPTY_PATH;
+
+        /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags>
+        const _ = !0;
+    }
+}
+
 /// `S_IF*` constants for use with [`mknodat`] and [`Stat`]'s `st_mode` field.
 ///
 /// [`mknodat`]: crate::fs::mknodat

src/backend/linux_raw/conv.rs

@@ -333,6 +333,13 @@ pub(crate) mod fs {
         }
     }
 
+    impl<'a, Num: ArgNumber> From<crate::fs::HandleFlags> for ArgReg<'a, Num> {
+        #[inline]
+        fn from(flags: crate::fs::HandleFlags) -> Self {
+            c_uint(flags.bits())
+        }
+    }
+
     impl<'a, Num: ArgNumber> From<crate::fs::XattrFlags> for ArgReg<'a, Num> {
         #[inline]
         fn from(flags: crate::fs::XattrFlags) -> Self {

src/backend/linux_raw/fs/types.rs

@@ -320,6 +320,34 @@ bitflags! {
     }
 }
 
+#[cfg(target_os = "linux")]
+bitflags! {
+    /// `AT_*` constants for use with [`name_to_handle_at`]
+    ///
+    /// [`name_to_handle_at`]: crate::fs::name_to_handle_at
+    #[repr(transparent)]
+    #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
+    pub struct HandleFlags: ffi::c_uint {
+        /// `AT_HANDLE_FID`
+        const FID = linux_raw_sys::general::AT_HANDLE_FID;
+
+        /// `AT_HANDLE_MNT_ID_UNIQUE`
+        const MNT_ID_UNIQUE = linux_raw_sys::general::AT_HANDLE_MNT_ID_UNIQUE;
+
+        /// `AT_HANDLE_CONNECTABLE`
+        const CONNECTABLE = linux_raw_sys::general::AT_HANDLE_CONNECTABLE;
+
+        /// `AT_SYMLINK_FOLLOW`
+        const SYMLINK_FOLLOW = linux_raw_sys::general::AT_SYMLINK_FOLLOW;
+
+        /// `AT_EMPTY_PATH`
+        const EMPTY_PATH = linux_raw_sys::general::AT_EMPTY_PATH;
+
+        /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags>
+        const _ = !0;
+    }
+}
+
 /// `S_IF*` constants for use with [`mknodat`] and [`Stat`]'s `st_mode` field.
 ///
 /// [`mknodat`]: crate::fs::mknodat