Change io crate & add a small shell

src/virtual_fs/virtual_stdin.rs

@@ -1,5 +1,5 @@
 use alloc::{boxed::Box, format};
-use io::{IoBase, Read, Seek, Write};
+use io::{Read, Seek, Write};
 
 use crate::{
     scheduler::ACTIVE_PID,
@@ -22,21 +22,18 @@ impl VirtualFileSystem for VirtualStdin {
     fn open(
         &mut self,
         path: &bffs::path::Path,
-    ) -> Result<alloc::boxed::Box<dyn crate::virtual_fs::VirtualNode + '_>, ()> {
+    ) -> Result<alloc::boxed::Box<dyn crate::virtual_fs::VirtualNode + '_>, io::Error> {
         if !path.is_empty() {
-            Err(())
+            Err(io::Error::from(io::ErrorKind::NotADirectory))
         } else {
             Ok(Box::new(VirtualStdinNode {}))
         }
     }
 }
 
-impl IoBase for VirtualStdinNode {
-    type Error = ();
-}
 
 impl Read for VirtualStdinNode {
-    fn read(&mut self, buf: &mut [u8]) -> Result<usize, Self::Error> {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, io::Error> {
         let pid = ACTIVE_PID.load(core::sync::atomic::Ordering::Relaxed);
         unsafe {
             FILE_SYSTEM
@@ -48,7 +45,7 @@ impl Read for VirtualStdinNode {
 }
 
 impl Seek for VirtualStdinNode {
-    fn seek(&mut self, pos: io::SeekFrom) -> Result<u64, Self::Error> {
+    fn seek(&mut self, pos: io::SeekFrom) -> Result<u64, io::Error> {
         let pid = ACTIVE_PID.load(core::sync::atomic::Ordering::Relaxed);
         unsafe {
             FILE_SYSTEM
@@ -60,7 +57,7 @@ impl Seek for VirtualStdinNode {
 }
 
 impl Write for VirtualStdinNode {
-    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::Error> {
+    fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
         let pid = ACTIVE_PID.load(core::sync::atomic::Ordering::Relaxed);
         unsafe {
             FILE_SYSTEM
@@ -70,7 +67,7 @@ impl Write for VirtualStdinNode {
         }
     }
 
-    fn flush(&mut self) -> Result<(), Self::Error> {
+    fn flush(&mut self) -> Result<(), io::Error> {
         let pid = ACTIVE_PID.load(core::sync::atomic::Ordering::Relaxed);
         unsafe {
             FILE_SYSTEM