adds support for AF_IUCV sockets

src/lib.rs

@@ -224,6 +224,14 @@ impl Domain {
     /// Domain for IPv6 communication, corresponding to `AF_INET6`.
     pub const IPV6: Domain = Domain(sys::AF_INET6);
 
+    #[cfg(all(
+        feature = "all",
+        any(target_arch = "x86_64", target_arch = "s390x"),
+        target_env = "gnu"
+    ))]
+    /// Domain for IUCV socket communication, corresponding to `AF_IUCV`.
+    pub const IUCV: Domain = Domain(sys::AF_IUCV);
+
     /// Domain for Unix socket communication, corresponding to `AF_UNIX`.
     #[cfg(not(target_os = "wasi"))]
     pub const UNIX: Domain = Domain(sys::AF_UNIX);

src/sockaddr.rs

@@ -223,6 +223,19 @@ impl SockAddr {
         crate::sys::unix_sockaddr(path.as_ref())
     }
 
+    #[cfg(all(
+        feature = "all",
+        any(target_arch = "x86_64", target_arch = "s390x"),
+        target_env = "gnu"
+    ))]
+    /// Constructs a `SockAddr` with the family `AF_IUCV` and the provided
+    /// components.
+    ///
+    /// Returns an error if the path is too long.
+    pub fn iucv(userid: &str, name: &str) -> io::Result<SockAddr> {
+        crate::sys::iucv_sockaddr(userid, name)
+    }
+
     /// Set the length of the address.
     ///
     /// # Safety
@@ -278,6 +291,16 @@ impl SockAddr {
         self.storage.ss_family == AF_UNIX as sa_family_t
     }
 
+    /// Returns true if this address is of an IUCV socket, false otherwise
+    #[cfg(all(
+        feature = "all",
+        any(target_arch = "x86_64", target_arch = "s390x"),
+        target_env = "gnu"
+    ))]
+    pub const fn is_iucv(&self) -> bool {
+        self.storage.ss_family == libc::AF_IUCV as sa_family_t
+    }
+
     /// Returns this address as a `SocketAddr` if it is in the `AF_INET` (IPv4)
     /// or `AF_INET6` (IPv6) family, otherwise returns `None`.
     pub fn as_socket(&self) -> Option<SocketAddr> {

src/sys/unix.rs

@@ -79,6 +79,14 @@ pub(crate) use std::ffi::c_int;
 #[cfg(not(target_os = "wasi"))]
 pub(crate) use libc::AF_UNIX;
 pub(crate) use libc::{AF_INET, AF_INET6};
+
+#[cfg(all(
+    feature = "all",
+    any(target_arch = "x86_64", target_arch = "s390x"),
+    target_env = "gnu"
+))]
+pub(crate) use libc::AF_IUCV;
+
 // Used in `Type`.
 #[cfg(all(feature = "all", target_os = "linux"))]
 pub(crate) use libc::SOCK_DCCP;
@@ -765,6 +773,51 @@ pub(crate) fn unix_sockaddr(path: &Path) -> io::Result<SockAddr> {
     Ok(unsafe { SockAddr::new(storage, len as socklen_t) })
 }
 
+#[cfg(all(
+    feature = "all",
+    any(target_arch = "x86_64", target_arch = "s390x"),
+    target_env = "gnu"
+))]
+fn copy_and_pad_with_spaces(src: &str, target: &mut [libc::c_char; 8]) -> io::Result<()> {
+    let bytes = src.as_bytes();
+    if bytes.len() > target.len() {
+        return Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            "IUCV address component is too long",
+        ));
+    }
+    let mut bytes_iter = bytes.iter();
+    for c in target {
+        if let Some(b) = bytes_iter.next() {
+            *c = *b as libc::c_char;
+        } else {
+            *c = b' ' as libc::c_char;
+        }
+    }
+    Ok(())
+}
+
+#[cfg(all(
+    feature = "all",
+    any(target_arch = "x86_64", target_arch = "s390x"),
+    target_env = "gnu"
+))]
+pub(crate) fn iucv_sockaddr(userid: &str, name: &str) -> io::Result<SockAddr> {
+    let mut storage = SockAddrStorage::zeroed();
+    {
+        // SAFETY: sockaddr_iucv is one of the sockaddr_* types defined by this platform.
+        let storage = unsafe { storage.view_as::<libc::sockaddr_iucv>() };
+
+        storage.siucv_family = libc::AF_IUCV as sa_family_t;
+        // Note that storage.siucv_port is initialized to zero above, which is required for the reserved field
+        // Note that storage.siucv_addr is initialized to zero above, which is required for the reserved field
+        storage.siucv_nodeid = [b' ' as libc::c_char; 8]; // Required for the reserved field
+        copy_and_pad_with_spaces(userid, &mut storage.siucv_user_id)?;
+        copy_and_pad_with_spaces(name, &mut storage.siucv_name)?;
+    }
+    Ok(unsafe { SockAddr::new(storage, mem::size_of::<libc::sockaddr_iucv>() as socklen_t) })
+}
+
 // Used in `MsgHdr`.
 #[cfg(not(any(target_os = "redox", target_os = "wasi", target_os = "horizon")))]
 pub(crate) use libc::msghdr;