3 files changed, 79 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/linux_raw/shm/mod.rs b/vendor/rustix/src/backend/linux_raw/shm/mod.rs
new file mode 100644
index 000000000..1e0181a99
--- /dev/null
+++ b/vendor/rustix/src/backend/linux_raw/shm/mod.rs
@@ -0,0 +1,2 @@
+pub(crate) mod syscalls;
+pub(crate) mod types;
diff --git a/vendor/rustix/src/backend/linux_raw/shm/syscalls.rs b/vendor/rustix/src/backend/linux_raw/shm/syscalls.rs
new file mode 100644
index 000000000..3b083f4b5
--- /dev/null
+++ b/vendor/rustix/src/backend/linux_raw/shm/syscalls.rs
@@ -0,0 +1,47 @@
+use crate::ffi::CStr;
+
+use crate::backend::fs::syscalls::{open, unlink};
+use crate::backend::fs::types::{Mode, OFlags};
+use crate::fd::OwnedFd;
+use crate::io;
+use crate::shm::ShmOFlags;
+
+const NAME_MAX: usize = 255;
+const SHM_DIR: &[u8] = b"/dev/shm/";
+
+fn get_shm_name(name: &CStr) -> io::Result<([u8; NAME_MAX + SHM_DIR.len() + 1], usize)> {
+    let name = name.to_bytes();
+
+    if name.len() > NAME_MAX {
+        return Err(io::Errno::NAMETOOLONG);
+    }
+
+    let num_slashes = name.iter().take_while(|x| **x == b'/').count();
+    let after_slashes = &name[num_slashes..];
+    if after_slashes.is_empty()
+        || after_slashes == b"."
+        || after_slashes == b".."
+        || after_slashes.contains(&b'/')
+    {
+        return Err(io::Errno::INVAL);
+    }
+
+    let mut path = [0; NAME_MAX + SHM_DIR.len() + 1];
+    path[..SHM_DIR.len()].copy_from_slice(SHM_DIR);
+    path[SHM_DIR.len()..SHM_DIR.len() + name.len()].copy_from_slice(name);
+    Ok((path, SHM_DIR.len() + name.len() + 1))
+}
+
+pub(crate) fn shm_open(name: &CStr, oflags: ShmOFlags, mode: Mode) -> io::Result<OwnedFd> {
+    let (path, len) = get_shm_name(name)?;
+    open(
+        CStr::from_bytes_with_nul(&path[..len]).unwrap(),
+        OFlags::from_bits(oflags.bits()).unwrap() | OFlags::CLOEXEC,
+        mode,
+    )
+}
+
+pub(crate) fn shm_unlink(name: &CStr) -> io::Result<()> {
+    let (path, len) = get_shm_name(name)?;
+    unlink(CStr::from_bytes_with_nul(&path[..len]).unwrap())
+}
diff --git a/vendor/rustix/src/backend/linux_raw/shm/types.rs b/vendor/rustix/src/backend/linux_raw/shm/types.rs
new file mode 100644
index 000000000..3343d4424
--- /dev/null
+++ b/vendor/rustix/src/backend/linux_raw/shm/types.rs
@@ -0,0 +1,30 @@
+use crate::backend::c;
+use bitflags::bitflags;
+
+bitflags! {
+    /// `O_*` constants for use with [`shm_open`].
+    ///
+    /// [`shm_open`]: crate:shm::shm_open
+    #[repr(transparent)]
+    #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
+    pub struct ShmOFlags: c::c_uint {
+        /// `O_CREAT`
+        #[doc(alias = "CREAT")]
+        const CREATE = linux_raw_sys::general::O_CREAT;
+
+        /// `O_EXCL`
+        const EXCL = linux_raw_sys::general::O_EXCL;
+
+        /// `O_RDONLY`
+        const RDONLY = linux_raw_sys::general::O_RDONLY;
+
+        /// `O_RDWR`
+        const RDWR = linux_raw_sys::general::O_RDWR;
+
+        /// `O_TRUNC`
+        const TRUNC = linux_raw_sys::general::O_TRUNC;
+
+        /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags>
+        const _ = !0;
+    }
+}