Reorganize Stat, Statx, and SockaddrStorage (#1282)

* Reorganize Stat, Statx, and SockaddrStorage

Remove linux-raw-sys types for `stat`, `statx`, and
`__kernel_sockaddr_storage` from the public API. To do this,
define our own `Statx` struct.

This also enables moving `stx_attributes` to a bitflags type.

* Fix a test to clean up its "yes" processes.

* Add a `stat` test.

* Make a `__reserved` field `pub(crate)`.

* Add ways to read or clear the `sa_family` from a `SocketAddrStorage`.

Also, say "sa_family" instead of "ss_family" in most places.

* Add accessors to `SockaddrStorage` for accessing the storage.

Author: sunfishcode

src/backend/libc/c.rs

@@ -483,3 +483,33 @@ mod readwrite_pv64v2 {
     all(target_os = "linux", not(target_env = "gnu")),
 ))]
 pub(super) use readwrite_pv64v2::{preadv64v2 as preadv2, pwritev64v2 as pwritev2};
+
+// Rust's libc crate lacks statx for Non-glibc targets.
+#[cfg(feature = "fs")]
+#[cfg(all(
+    linux_like,
+    not(any(target_os = "android", target_os = "emscripten", target_env = "gnu"))
+))]
+mod statx_flags {
+    pub(crate) use linux_raw_sys::general::{
+        STATX_ALL, STATX_ATIME, STATX_BASIC_STATS, STATX_BLOCKS, STATX_BTIME, STATX_CTIME,
+        STATX_DIOALIGN, STATX_GID, STATX_INO, STATX_MNT_ID, STATX_MODE, STATX_MTIME, STATX_NLINK,
+        STATX_SIZE, STATX_TYPE, STATX_UID,
+    };
+
+    pub(crate) use linux_raw_sys::general::{
+        STATX_ATTR_APPEND, STATX_ATTR_AUTOMOUNT, STATX_ATTR_COMPRESSED, STATX_ATTR_DAX,
+        STATX_ATTR_ENCRYPTED, STATX_ATTR_IMMUTABLE, STATX_ATTR_MOUNT_ROOT, STATX_ATTR_NODUMP,
+        STATX_ATTR_VERITY,
+    };
+}
+#[cfg(feature = "fs")]
+#[cfg(all(
+    linux_like,
+    not(any(target_os = "android", target_os = "emscripten", target_env = "gnu"))
+))]
+pub(crate) use statx_flags::*;
+
+#[cfg(feature = "fs")]
+#[cfg(target_os = "android")]
+pub(crate) use libc::__fsid_t as fsid_t;

src/backend/libc/fs/types.rs

@@ -674,128 +674,6 @@ bitflags! {
     }
 }
 
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
-bitflags! {
-    /// `STATX_*` constants for use with [`statx`].
-    ///
-    /// [`statx`]: crate::fs::statx
-    #[repr(transparent)]
-    #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
-    pub struct StatxFlags: u32 {
-        /// `STATX_TYPE`
-        const TYPE = c::STATX_TYPE;
-
-        /// `STATX_MODE`
-        const MODE = c::STATX_MODE;
-
-        /// `STATX_NLINK`
-        const NLINK = c::STATX_NLINK;
-
-        /// `STATX_UID`
-        const UID = c::STATX_UID;
-
-        /// `STATX_GID`
-        const GID = c::STATX_GID;
-
-        /// `STATX_ATIME`
-        const ATIME = c::STATX_ATIME;
-
-        /// `STATX_MTIME`
-        const MTIME = c::STATX_MTIME;
-
-        /// `STATX_CTIME`
-        const CTIME = c::STATX_CTIME;
-
-        /// `STATX_INO`
-        const INO = c::STATX_INO;
-
-        /// `STATX_SIZE`
-        const SIZE = c::STATX_SIZE;
-
-        /// `STATX_BLOCKS`
-        const BLOCKS = c::STATX_BLOCKS;
-
-        /// `STATX_BASIC_STATS`
-        const BASIC_STATS = c::STATX_BASIC_STATS;
-
-        /// `STATX_BTIME`
-        const BTIME = c::STATX_BTIME;
-
-        /// `STATX_MNT_ID` (since Linux 5.8)
-        const MNT_ID = c::STATX_MNT_ID;
-
-        /// `STATX_DIOALIGN` (since Linux 6.1)
-        const DIOALIGN = c::STATX_DIOALIGN;
-
-        /// `STATX_ALL`
-        const ALL = c::STATX_ALL;
-
-        /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags>
-        const _ = !0;
-    }
-}
-
-#[cfg(any(
-    target_os = "android",
-    all(target_os = "linux", not(target_env = "gnu")),
-))]
-bitflags! {
-    /// `STATX_*` constants for use with [`statx`].
-    ///
-    /// [`statx`]: crate::fs::statx
-    #[repr(transparent)]
-    #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
-    pub struct StatxFlags: u32 {
-        /// `STATX_TYPE`
-        const TYPE = 0x0001;
-
-        /// `STATX_MODE`
-        const MODE = 0x0002;
-
-        /// `STATX_NLINK`
-        const NLINK = 0x0004;
-
-        /// `STATX_UID`
-        const UID = 0x0008;
-
-        /// `STATX_GID`
-        const GID = 0x0010;
-
-        /// `STATX_ATIME`
-        const ATIME = 0x0020;
-
-        /// `STATX_MTIME`
-        const MTIME = 0x0040;
-
-        /// `STATX_CTIME`
-        const CTIME = 0x0080;
-
-        /// `STATX_INO`
-        const INO = 0x0100;
-
-        /// `STATX_SIZE`
-        const SIZE = 0x0200;
-
-        /// `STATX_BLOCKS`
-        const BLOCKS = 0x0400;
-
-        /// `STATX_BASIC_STATS`
-        const BASIC_STATS = 0x07ff;
-
-        /// `STATX_BTIME`
-        const BTIME = 0x800;
-
-        /// `STATX_MNT_ID` (since Linux 5.8)
-        const MNT_ID = 0x1000;
-
-        /// `STATX_ALL`
-        const ALL = 0xfff;
-
-        /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags>
-        const _ = !0;
-    }
-}
-
 #[cfg(not(any(
     netbsdlike,
     target_os = "espidf",
@@ -1022,13 +900,12 @@ pub type Stat = c::stat64;
 // we use our own struct, populated from `statx` where possible, to avoid the
 // y2038 bug.
 #[cfg(all(linux_kernel, target_pointer_width = "32"))]
-#[repr(C)]
 #[derive(Debug, Copy, Clone)]
 #[allow(missing_docs)]
 pub struct Stat {
     pub st_dev: u64,
     pub st_mode: u32,
-    pub st_nlink: u32,
+    pub st_nlink: u64,
     pub st_uid: u32,
     pub st_gid: u32,
     pub st_rdev: u64,
@@ -1069,6 +946,16 @@ pub type StatFs = c::statfs;
 #[cfg(linux_like)]
 pub type StatFs = c::statfs64;
 
+/// `fsid_t` for use with `StatFs`.
+#[cfg(not(any(
+    solarish,
+    target_os = "haiku",
+    target_os = "nto",
+    target_os = "redox",
+    target_os = "wasi"
+)))]
+pub type Fsid = c::fsid_t;
+
 /// `struct statvfs` for use with [`statvfs`] and [`fstatvfs`].
 ///
 /// [`statvfs`]: crate::fs::statvfs
@@ -1089,70 +976,6 @@ pub struct StatVfs {
     pub f_namemax: u64,
 }
 
-/// `struct statx` for use with [`statx`].
-///
-/// [`statx`]: crate::fs::statx
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
-// Use the glibc `struct statx`.
-pub type Statx = c::statx;
-
-/// `struct statx_timestamp` for use with [`Statx`].
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
-// Use the glibc `struct statx_timestamp`.
-pub type StatxTimestamp = c::statx;
-
-/// `struct statx` for use with [`statx`].
-///
-/// [`statx`]: crate::fs::statx
-// Non-glibc ABIs don't currently declare a `struct statx`, so we declare it
-// ourselves.
-#[cfg(any(
-    target_os = "android",
-    all(target_os = "linux", not(target_env = "gnu")),
-))]
-#[repr(C)]
-#[allow(missing_docs)]
-pub struct Statx {
-    pub stx_mask: u32,
-    pub stx_blksize: u32,
-    pub stx_attributes: u64,
-    pub stx_nlink: u32,
-    pub stx_uid: u32,
-    pub stx_gid: u32,
-    pub stx_mode: u16,
-    __statx_pad1: [u16; 1],
-    pub stx_ino: u64,
-    pub stx_size: u64,
-    pub stx_blocks: u64,
-    pub stx_attributes_mask: u64,
-    pub stx_atime: StatxTimestamp,
-    pub stx_btime: StatxTimestamp,
-    pub stx_ctime: StatxTimestamp,
-    pub stx_mtime: StatxTimestamp,
-    pub stx_rdev_major: u32,
-    pub stx_rdev_minor: u32,
-    pub stx_dev_major: u32,
-    pub stx_dev_minor: u32,
-    pub stx_mnt_id: u64,
-    __statx_pad2: u64,
-    __statx_pad3: [u64; 12],
-}
-
-/// `struct statx_timestamp` for use with [`Statx`].
-// Non-glibc ABIs don't currently declare a `struct statx_timestamp`, so we
-// declare it ourselves.
-#[cfg(any(
-    target_os = "android",
-    all(target_os = "linux", not(target_env = "gnu")),
-))]
-#[repr(C)]
-#[allow(missing_docs)]
-pub struct StatxTimestamp {
-    pub tv_sec: i64,
-    pub tv_nsec: u32,
-    pub __statx_timestamp_pad1: [i32; 1],
-}
-
 /// `mode_t`
 #[cfg(not(all(target_os = "android", target_pointer_width = "32")))]
 pub type RawMode = c::mode_t;

src/backend/libc/io/errno.rs

@@ -782,7 +782,7 @@ impl Errno {
     #[cfg(not(target_os = "l4re"))]
     pub const NOTSOCK: Self = Self(c::ENOTSOCK);
     /// `ENOTSUP`
-    #[cfg(not(any(windows, target_os = "haiku", target_os = "redox")))]
+    #[cfg(not(any(windows, target_os = "redox")))]
     pub const NOTSUP: Self = Self(c::ENOTSUP);
     /// `ENOTTY`
     #[cfg(not(windows))]

src/backend/libc/net/addr.rs

@@ -1,6 +1,9 @@
 //! Socket address utilities.
 
 use crate::backend::c;
+use crate::net::AddressFamily;
+use core::mem::size_of;
+use core::slice;
 #[cfg(unix)]
 use {
     crate::ffi::CStr,
@@ -9,7 +12,6 @@ use {
     core::cmp::Ordering,
     core::fmt,
     core::hash::{Hash, Hasher},
-    core::slice,
 };
 
 /// `struct sockaddr_un`
@@ -208,8 +210,48 @@ impl fmt::Debug for SocketAddrUnix {
     }
 }
 
-/// `struct sockaddr_storage` as a raw struct.
-pub type SocketAddrStorage = c::sockaddr_storage;
+/// `struct sockaddr_storage`.
+#[repr(transparent)]
+pub struct SocketAddrStorage(c::sockaddr_storage);
+
+impl SocketAddrStorage {
+    /// Return a socket addr storage initialized to all zero bytes. The
+    /// `sa_family` is set to `AddressFamily::UNSPEC`.
+    pub fn zeroed() -> Self {
+        assert_eq!(c::AF_UNSPEC, 0);
+        // SAFETY: `sockaddr_storage` is meant to be zero-initializable.
+        unsafe { core::mem::zeroed() }
+    }
+
+    /// Return the `sa_family` of this socket address.
+    pub fn family(&self) -> AddressFamily {
+        unsafe {
+            AddressFamily::from_raw(crate::backend::net::read_sockaddr::read_sa_family(
+                crate::utils::as_ptr(&self.0).cast::<c::sockaddr>(),
+            ))
+        }
+    }
+
+    /// Clear the `sa_family` of this socket address to
+    /// `AddressFamily::UNSPEC`.
+    pub fn clear_family(&mut self) {
+        unsafe {
+            crate::backend::net::read_sockaddr::initialize_family_to_unspec(
+                crate::utils::as_mut_ptr(&mut self.0).cast::<c::sockaddr>(),
+            )
+        }
+    }
+
+    /// View the storage as a byte slice.
+    pub fn as_mut_bytes(&mut self) -> &mut [u8] {
+        unsafe {
+            slice::from_raw_parts_mut(
+                crate::utils::as_mut_ptr(self).cast::<u8>(),
+                size_of::<Self>(),
+            )
+        }
+    }
+}
 
 /// Return the offset of the `sun_path` field of `sockaddr_un`.
 #[cfg(not(windows))]