Refactored shared code from try_statx and Metadata::from_statx into a function with FileAttr::from_statx

Author: asder8215

library/std/src/os/linux/fs.rs

@@ -4,16 +4,14 @@
 
 #![stable(feature = "metadata_ext", since = "1.1.0")]
 
-use core::mem;
-
 use crate::fs::Metadata;
 #[allow(deprecated)]
 use crate::os::linux::raw;
 use crate::os::raw::{c_uint, c_void};
 use crate::sys::AsInner;
 use crate::sys::fs::cfg_has_statx;
 cfg_has_statx! {{
-    use crate::sys::fs::{FileAttr, StatxExtraFields};
+    use crate::sys::fs::FileAttr;
     use crate::sys::FromInner;
 } else {
     use crate::sys::unsupported;
@@ -405,32 +403,7 @@ impl MetadataExt for Metadata {
     }
     cfg_has_statx! {{
         unsafe fn from_statx(statxbuf: *const c_void) -> Metadata {
-            let buf =  statxbuf as *const libc::statx;
-
-            // We cannot fill `stat64` exhaustively because of private padding fields.
-            let mut stat: libc::stat64 = mem::zeroed();
-            // `c_ulong` on gnu-mips, `dev_t` otherwise
-            stat.st_dev = libc::makedev((*buf).stx_dev_major, (*buf).stx_dev_minor) as _;
-            stat.st_ino = (*buf).stx_ino as libc::ino64_t;
-            stat.st_nlink = (*buf).stx_nlink as libc::nlink_t;
-            stat.st_mode = (*buf).stx_mode as libc::mode_t;
-            stat.st_uid = (*buf).stx_uid as libc::uid_t;
-            stat.st_gid = (*buf).stx_gid as libc::gid_t;
-            stat.st_rdev = libc::makedev((*buf).stx_rdev_major, (*buf).stx_rdev_minor) as _;
-            stat.st_size = (*buf).stx_size as libc::off64_t;
-            stat.st_blksize = (*buf).stx_blksize as libc::blksize_t;
-            stat.st_blocks = (*buf).stx_blocks as libc::blkcnt64_t;
-            stat.st_atime = (*buf).stx_atime.tv_sec as libc::time_t;
-            // `i64` on gnu-x86_64-x32, `c_ulong` otherwise.
-            stat.st_atime_nsec = (*buf).stx_atime.tv_nsec as _;
-            stat.st_mtime = (*buf).stx_mtime.tv_sec as libc::time_t;
-            stat.st_mtime_nsec = (*buf).stx_mtime.tv_nsec as _;
-            stat.st_ctime = (*buf).stx_ctime.tv_sec as libc::time_t;
-            stat.st_ctime_nsec = (*buf).stx_ctime.tv_nsec as _;
-
-            let extra = StatxExtraFields::from_statx(statxbuf);
-
-            Metadata::from_inner(FileAttr::from_statx(stat, Some(extra)))
+            Metadata::from_inner(FileAttr::from_statx(*(statxbuf as *const libc::statx)))
         }} else {
             unsafe fn from_statx(statxbuf: *const c_void) -> Self {
                 unsupported();

library/std/src/sys/fs/mod.rs

@@ -19,9 +19,7 @@ cfg_select! {
         pub(super) use unix::CachedFileMetadata;
         use crate::sys::helpers::run_path_with_cstr as with_native_path;
         #[cfg(all(target_os = "linux", target_env = "gnu"))]
-        pub(crate) use unix::{
-            cfg_has_statx, StatxExtraFields
-        };
+        pub(crate) use unix::cfg_has_statx;
     }
     target_os = "windows" => {
         mod windows;

library/std/src/sys/fs/unix.rs

@@ -83,9 +83,6 @@ use crate::fmt::{self, Write as _};
 use crate::fs::TryLockError;
 use crate::io::{self, BorrowedCursor, Error, IoSlice, IoSliceMut, SeekFrom};
 use crate::os::fd::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd};
-cfg_has_statx! {{
-    use crate::os::raw::c_void;
-} else {}}
 #[cfg(target_family = "unix")]
 use crate::os::unix::prelude::*;
 #[cfg(target_os = "wasi")]
@@ -128,6 +125,7 @@ macro_rules! cfg_has_statx {
     };
 }
 
+#[cfg(all(target_os = "linux", target_env = "gnu"))]
 pub(crate) use cfg_has_statx;
 
 cfg_has_statx! {{
@@ -217,40 +215,7 @@ cfg_has_statx! {{
             STATX_SAVED_STATE.store(STATX_STATE::Present as u8, Ordering::Relaxed);
         }
 
-        // We cannot fill `stat64` exhaustively because of private padding fields.
-        let mut stat: stat64 = mem::zeroed();
-        // `c_ulong` on gnu-mips, `dev_t` otherwise
-        stat.st_dev = libc::makedev(buf.stx_dev_major, buf.stx_dev_minor) as _;
-        stat.st_ino = buf.stx_ino as libc::ino64_t;
-        stat.st_nlink = buf.stx_nlink as libc::nlink_t;
-        stat.st_mode = buf.stx_mode as libc::mode_t;
-        stat.st_uid = buf.stx_uid as libc::uid_t;
-        stat.st_gid = buf.stx_gid as libc::gid_t;
-        stat.st_rdev = libc::makedev(buf.stx_rdev_major, buf.stx_rdev_minor) as _;
-        stat.st_size = buf.stx_size as off64_t;
-        stat.st_blksize = buf.stx_blksize as libc::blksize_t;
-        stat.st_blocks = buf.stx_blocks as libc::blkcnt64_t;
-        stat.st_atime = buf.stx_atime.tv_sec as libc::time_t;
-        // `i64` on gnu-x86_64-x32, `c_ulong` otherwise.
-        stat.st_atime_nsec = buf.stx_atime.tv_nsec as _;
-        stat.st_mtime = buf.stx_mtime.tv_sec as libc::time_t;
-        stat.st_mtime_nsec = buf.stx_mtime.tv_nsec as _;
-        stat.st_ctime = buf.stx_ctime.tv_sec as libc::time_t;
-        stat.st_ctime_nsec = buf.stx_ctime.tv_nsec as _;
-
-        let extra = StatxExtraFields {
-            stx_mask: buf.stx_mask,
-            stx_btime: buf.stx_btime,
-            // Store full times to avoid 32-bit `time_t` truncation.
-            #[cfg(target_pointer_width = "32")]
-            stx_atime: buf.stx_atime,
-            #[cfg(target_pointer_width = "32")]
-            stx_ctime: buf.stx_ctime,
-            #[cfg(target_pointer_width = "32")]
-            stx_mtime: buf.stx_mtime,
-        };
-
-        Some(Ok(FileAttr { stat, statx_extra_fields: Some(extra) }))
+        Some(Ok(FileAttr::from_statx(buf)))
     }
 
 } else {
@@ -531,19 +496,23 @@ struct Mode(mode_t);
 
 cfg_has_statx! {{
     impl StatxExtraFields {
-        pub unsafe fn from_statx(statxbuf: *const c_void) -> Self {
-            let buf =  statxbuf as *const libc::statx;
-
+        /// Constructs `StatxExtraFields` from a given `libc::statx` struct
+        ///
+        /// SAFETY:
+        /// The caller must take care to provide a `libc::statx` buffer that is
+        /// populated by the statx syscall with the flags `STATX_BASIC_STATS`
+        /// and `STATX_BTIME` enabled
+        pub unsafe fn from_statx(buf: libc::statx) -> Self {
             StatxExtraFields {
-                stx_mask: (*buf).stx_mask,
-                stx_btime: (*buf).stx_btime,
+                stx_mask: buf.stx_mask,
+                stx_btime: buf.stx_btime,
                 // Store full times to avoid 32-bit `time_t` truncation.
                 #[cfg(target_pointer_width = "32")]
-                stx_atime: (*buf).stx_atime,
+                stx_atime: buf.stx_atime,
                 #[cfg(target_pointer_width = "32")]
-                stx_ctime: (*buf).stx_ctime,
+                stx_ctime: buf.stx_ctime,
                 #[cfg(target_pointer_width = "32")]
-                stx_mtime: (*buf).stx_mtime,
+                stx_mtime: buf.stx_mtime,
             }
         }
     }
@@ -552,8 +521,37 @@ cfg_has_statx! {{
             Self { stat, statx_extra_fields: None }
         }
 
-        pub fn from_statx(stat: stat64, extra: Option<StatxExtraFields>) -> Self {
-            Self {stat, statx_extra_fields: extra}
+        /// Constructs `FileAttr` from a given `libc::statx` struct
+        ///
+        /// SAFETY:
+        /// The caller must take care to provide a `libc::statx` buffer that is
+        /// populated by the statx syscall with the flags `STATX_BASIC_STATS`
+        /// and `STATX_BTIME` enabled
+        pub unsafe fn from_statx(buf: libc::statx) -> Self {
+            // We cannot fill `stat64` exhaustively because of private padding fields.
+            let mut stat: libc::stat64 = mem::zeroed();
+            // `c_ulong` on gnu-mips, `dev_t` otherwise
+            stat.st_dev = libc::makedev((buf).stx_dev_major, (buf).stx_dev_minor) as _;
+            stat.st_ino = buf.stx_ino as libc::ino64_t;
+            stat.st_nlink = buf.stx_nlink as libc::nlink_t;
+            stat.st_mode = buf.stx_mode as libc::mode_t;
+            stat.st_uid = buf.stx_uid as libc::uid_t;
+            stat.st_gid = buf.stx_gid as libc::gid_t;
+            stat.st_rdev = libc::makedev(buf.stx_rdev_major, buf.stx_rdev_minor) as _;
+            stat.st_size = buf.stx_size as libc::off64_t;
+            stat.st_blksize = buf.stx_blksize as libc::blksize_t;
+            stat.st_blocks = buf.stx_blocks as libc::blkcnt64_t;
+            stat.st_atime = buf.stx_atime.tv_sec as libc::time_t;
+            // `i64` on gnu-x86_64-x32, `c_ulong` otherwise.
+            stat.st_atime_nsec = buf.stx_atime.tv_nsec as _;
+            stat.st_mtime = buf.stx_mtime.tv_sec as libc::time_t;
+            stat.st_mtime_nsec = buf.stx_mtime.tv_nsec as _;
+            stat.st_ctime = buf.stx_ctime.tv_sec as libc::time_t;
+            stat.st_ctime_nsec = buf.stx_ctime.tv_nsec as _;
+
+            let statx_extra_fields = Some(StatxExtraFields::from_statx(buf));
+
+            Self {stat, statx_extra_fields}
         }
 
         #[cfg(target_pointer_width = "32")]