od, uucore: Allow reusing RawReader (#12385)

src/uu/od/Cargo.toml

@@ -22,7 +22,7 @@ byteorder = { workspace = true }
 clap = { workspace = true }
 half = { workspace = true }
 rustix = { workspace = true, features = ["stdio"] }
-uucore = { workspace = true, features = ["parser-size"] }
+uucore = { workspace = true, features = ["fs", "parser-size"] }
 fluent = { workspace = true }
 libc.workspace = true
 

src/uu/od/src/multifile_reader.rs

@@ -56,15 +56,7 @@ impl MultifileReader<'_> {
                     // limit.
                     #[cfg(any(unix, target_os = "wasi"))]
                     {
-                        use std::os::fd::AsFd;
-                        // todo: definition is generic enough to move to uucore::io::RawReader if useful
-                        struct RawReader<T: AsFd>(pub T);
-                        impl<T: AsFd> io::Read for RawReader<T> {
-                            fn read(&mut self, b: &mut [u8]) -> io::Result<usize> {
-                                rustix::io::read(&self.0, b).map_err(Into::into)
-                            }
-                        }
-                        let stdin = RawReader(rustix::stdio::stdin());
+                        let stdin = uucore::io::RawReader(rustix::stdio::stdin());
                         self.curr_file = Some(Box::new(stdin));
                     }
 

src/uucore/src/lib/mods/io.rs

@@ -30,6 +30,16 @@ type NativeType = OwnedHandle;
 #[cfg(not(windows))]
 type NativeType = OwnedFd;
 
+// create reader without buffering
+#[cfg(any(unix, target_os = "wasi"))]
+pub struct RawReader<T: AsFd>(pub T);
+#[cfg(any(unix, target_os = "wasi"))]
+impl<T: AsFd> io::Read for RawReader<T> {
+    fn read(&mut self, b: &mut [u8]) -> io::Result<usize> {
+        rustix::io::read(&self.0, b).map_err(Into::into)
+    }
+}
+
 // create writer without buffering
 #[cfg(any(unix, target_os = "wasi"))]
 pub struct RawWriter<T: AsFd>(pub T);