Enable std::io::copy specialisation for `std::pipe::{PipeReader, Pi…

…peWriter}`

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

library/std/src/sys/pal/unix/kernel_copy.rs

@@ -54,6 +54,7 @@ use crate::net::TcpStream;
 use crate::os::unix::fs::FileTypeExt;
 use crate::os::unix::io::{AsRawFd, FromRawFd, RawFd};
 use crate::os::unix::net::UnixStream;
+use crate::pipe::{PipeReader, PipeWriter};
 use crate::process::{ChildStderr, ChildStdin, ChildStdout};
 use crate::ptr;
 use crate::sync::atomic::{AtomicBool, AtomicU8, Ordering};
@@ -404,6 +405,30 @@ impl CopyWrite for &UnixStream {
     }
 }
 
+impl CopyRead for PipeReader {
+    fn properties(&self) -> CopyParams {
+        CopyParams(FdMeta::Pipe, Some(self.as_raw_fd()))
+    }
+}
+
+impl CopyRead for &PipeReader {
+    fn properties(&self) -> CopyParams {
+        CopyParams(FdMeta::Pipe, Some(self.as_raw_fd()))
+    }
+}
+
+impl CopyWrite for PipeWriter {
+    fn properties(&self) -> CopyParams {
+        CopyParams(FdMeta::Pipe, Some(self.as_raw_fd()))
+    }
+}
+
+impl CopyWrite for &PipeWriter {
+    fn properties(&self) -> CopyParams {
+        CopyParams(FdMeta::Pipe, Some(self.as_raw_fd()))
+    }
+}
+
 impl CopyWrite for ChildStdin {
     fn properties(&self) -> CopyParams {
         CopyParams(FdMeta::Pipe, Some(self.as_raw_fd()))