Add GNU/Hurd support

examples/stdio.rs

@@ -123,6 +123,7 @@ fn show<Fd: AsFd>(fd: Fd) -> io::Result<()> {
                 target_os = "aix",
                 target_os = "emscripten",
                 target_os = "haiku",
+                target_os = "hurd",
                 target_os = "redox",
             )))]
             if term.input_modes.contains(InputModes::IUTF8) {
@@ -217,6 +218,7 @@ fn show<Fd: AsFd>(fd: Fd) -> io::Result<()> {
                 solarish,
                 target_os = "emscripten",
                 target_os = "haiku",
+                target_os = "hurd",
                 target_os = "redox",
             )))]
             if term.control_modes.contains(ControlModes::CMSPAR) {
@@ -297,6 +299,7 @@ fn show<Fd: AsFd>(fd: Fd) -> io::Result<()> {
                 solarish,
                 target_os = "aix",
                 target_os = "haiku",
+                target_os = "hurd",
                 target_os = "nto",
             )))]
             println!(

src/backend/libc/c.rs

@@ -109,7 +109,7 @@ pub(super) use libc::fallocate64 as fallocate;
 #[cfg(not(any(target_arch = "aarch64", target_arch = "riscv64")))]
 #[cfg(any(linux_like, target_os = "aix"))]
 pub(super) use libc::open64 as open;
-#[cfg(any(linux_kernel, target_os = "aix", target_os = "l4re"))]
+#[cfg(any(linux_kernel, target_os = "aix", target_os = "hurd", target_os = "l4re"))]
 pub(super) use libc::posix_fallocate64 as posix_fallocate;
 #[cfg(any(all(linux_like, not(target_os = "android")), target_os = "aix"))]
 pub(super) use libc::{blkcnt64_t as blkcnt_t, rlim64_t as rlim_t};
@@ -123,7 +123,7 @@ pub(super) use libc::{
     rlimit64 as rlimit, setrlimit64 as setrlimit, statfs64 as statfs, statvfs64 as statvfs,
     RLIM_INFINITY,
 };
-#[cfg(linux_like)]
+#[cfg(any(linux_like, target_os = "hurd"))]
 pub(super) use libc::{
     fstat64 as fstat, fstatat64 as fstatat, fstatfs64 as fstatfs, fstatvfs64 as fstatvfs,
     ftruncate64 as ftruncate, getrlimit64 as getrlimit, ino64_t as ino_t, lseek64 as lseek,
@@ -144,11 +144,11 @@ pub(super) use libc::{
         target_arch = "mips64r6"
     )
 )))]
-#[cfg(any(linux_like, target_os = "aix"))]
+#[cfg(any(linux_like, target_os = "aix", target_os = "hurd"))]
 pub(super) use libc::{lstat64 as lstat, stat64 as stat};
-#[cfg(any(linux_kernel, target_os = "aix", target_os = "emscripten"))]
+#[cfg(any(linux_kernel, target_os = "aix", target_os = "hurd", target_os = "emscripten"))]
 pub(super) use libc::{pread64 as pread, pwrite64 as pwrite};
-#[cfg(any(target_os = "linux", target_os = "emscripten"))]
+#[cfg(any(target_os = "linux", target_os = "hurd", target_os = "emscripten"))]
 pub(super) use libc::{preadv64 as preadv, pwritev64 as pwritev};
 
 #[cfg(all(target_os = "linux", target_env = "gnu"))]

src/backend/libc/fs/dir.rs

@@ -21,9 +21,9 @@ use crate::io;
 #[cfg(feature = "process")]
 use crate::process::fchdir;
 use alloc::borrow::ToOwned;
-#[cfg(not(linux_like))]
+#[cfg(not(any(linux_like, target_os = "hurd")))]
 use c::readdir as libc_readdir;
-#[cfg(linux_like)]
+#[cfg(any(linux_like, target_os = "hurd"))]
 use c::readdir64 as libc_readdir;
 use core::fmt;
 use core::ptr::NonNull;

src/backend/libc/fs/syscalls.rs

@@ -125,7 +125,7 @@ fn open_via_syscall(path: &CStr, oflags: OFlags, mode: Mode) -> io::Result<Owned
 pub(crate) fn open(path: &CStr, oflags: OFlags, mode: Mode) -> io::Result<OwnedFd> {
     // Work around <https://sourceware.org/bugzilla/show_bug.cgi?id=17523>.
     // glibc versions before 2.25 don't handle `O_TMPFILE` correctly.
-    #[cfg(all(unix, target_env = "gnu"))]
+    #[cfg(all(unix, target_env = "gnu", not(target_os = "hurd")))]
     if oflags.contains(OFlags::TMPFILE) && crate::backend::if_glibc_is_less_than_2_25() {
         return open_via_syscall(path, oflags, mode);
     }
@@ -153,7 +153,7 @@ pub(crate) fn open(path: &CStr, oflags: OFlags, mode: Mode) -> io::Result<OwnedF
 /// Use a direct syscall (via libc) for `openat`.
 ///
 /// This is only currently necessary as a workaround for old glibc; see below.
-#[cfg(all(unix, target_env = "gnu"))]
+#[cfg(all(unix, target_env = "gnu", not(target_os = "hurd")))]
 fn openat_via_syscall(
     dirfd: BorrowedFd<'_>,
     path: &CStr,
@@ -188,7 +188,7 @@ pub(crate) fn openat(
 ) -> io::Result<OwnedFd> {
     // Work around <https://sourceware.org/bugzilla/show_bug.cgi?id=17523>.
     // glibc versions before 2.25 don't handle `O_TMPFILE` correctly.
-    #[cfg(all(unix, target_env = "gnu"))]
+    #[cfg(all(unix, target_env = "gnu", not(target_os = "hurd")))]
     if oflags.contains(OFlags::TMPFILE) && crate::backend::if_glibc_is_less_than_2_25() {
         return openat_via_syscall(dirfd, path, oflags, mode);
     }

src/backend/libc/fs/types.rs

@@ -797,6 +797,7 @@ bitflags! {
             bsd,
             target_os = "aix",
             target_os = "haiku",
+            target_os = "hurd",
             target_os = "wasi",
         )))]
         const KEEP_SIZE = bitcast!(c::FALLOC_FL_KEEP_SIZE);
@@ -805,6 +806,7 @@ bitflags! {
             bsd,
             target_os = "aix",
             target_os = "haiku",
+            target_os = "hurd",
             target_os = "wasi",
         )))]
         const PUNCH_HOLE = bitcast!(c::FALLOC_FL_PUNCH_HOLE);
@@ -815,6 +817,7 @@ bitflags! {
             target_os = "emscripten",
             target_os = "fuchsia",
             target_os = "haiku",
+            target_os = "hurd",
             target_os = "l4re",
             target_os = "linux",
             target_os = "wasi",
@@ -825,6 +828,7 @@ bitflags! {
             bsd,
             target_os = "aix",
             target_os = "haiku",
+            target_os = "hurd",
             target_os = "emscripten",
             target_os = "wasi",
         )))]
@@ -834,6 +838,7 @@ bitflags! {
             bsd,
             target_os = "aix",
             target_os = "haiku",
+            target_os = "hurd",
             target_os = "emscripten",
             target_os = "wasi",
         )))]
@@ -843,6 +848,7 @@ bitflags! {
             bsd,
             target_os = "aix",
             target_os = "haiku",
+            target_os = "hurd",
             target_os = "emscripten",
             target_os = "wasi",
         )))]
@@ -852,6 +858,7 @@ bitflags! {
             bsd,
             target_os = "aix",
             target_os = "haiku",
+            target_os = "hurd",
             target_os = "emscripten",
             target_os = "wasi",
         )))]
@@ -940,7 +947,7 @@ pub enum FlockOperation {
 ///
 /// [`statat`]: crate::fs::statat
 /// [`fstat`]: crate::fs::fstat
-#[cfg(not(linux_like))]
+#[cfg(not(any(linux_like, target_os = "hurd")))]
 pub type Stat = c::stat;
 
 /// `struct stat` for use with [`statat`] and [`fstat`].
@@ -949,6 +956,7 @@ pub type Stat = c::stat;
 /// [`fstat`]: crate::fs::fstat
 #[cfg(any(
     all(linux_kernel, target_pointer_width = "64"),
+    target_os = "hurd",
     target_os = "emscripten",
     target_os = "l4re",
 ))]