Add simple shell

utility/main.rs

 extern crate redoxfs;
 
 use std::env;
+use std::io::{self, Write};
 
 use redoxfs::{Disk, FileSystem};
 
@@ -8,13 +9,23 @@ use file_disk::FileDisk;
 
 pub mod file_disk;
 
-fn main() {
-    let mut args = env::args();
-    if let Some(path) = args.nth(1) {
-        match FileDisk::new(&path) {
-            Ok(disk) => match FileSystem::new(Box::new(disk)) {
-                Ok(filesystem) => {
-                    let path = args.next().unwrap_or(String::new());
+fn shell<E>(filesystem: FileSystem<E>){
+    let mut stdout = io::stdout();
+    let stdin = io::stdin();
+
+    loop {
+        stdout.write(b"redoxfs# ").unwrap();
+        stdout.flush().unwrap();
+
+        let mut line = String::new();
+        stdin.read_line(&mut line).unwrap();
+
+        let mut args = line.trim().split(' ');
+        if let Some(command) = args.next() {
+            match command {
+                "" => (),
+                "ls" => {
+                    let path = args.next().unwrap_or("/");
                     for (node_block, node) in filesystem.nodes.iter() {
                         let mut name = "/".to_string();
                         for &b in node.name.iter() {
@@ -24,14 +35,23 @@ fn main() {
                                 unsafe { name.as_mut_vec().push(b); }
                             }
                         }
-                        if name == path {
-                            println!("{}: {}", node_block, name);
-                            break;
-                        } else if name.starts_with(&path) {
+                        if name.starts_with(&path) {
                             println!("{}: {}", node_block, name);
                         }
                     }
                 },
+                _ => println!("unknown command: {}", command)
+            }
+        }
+    }
+}
+
+fn main() {
+    let mut args = env::args();
+    if let Some(path) = args.nth(1) {
+        match FileDisk::new(&path) {
+            Ok(disk) => match FileSystem::new(Box::new(disk)) {
+                Ok(filesystem) => shell(filesystem),
                 Err(err) => {
                     println!("redoxfs: failed to open filesystem: {}", err);
                 }