Merge pull request #2 from skylerberg/master

Sync ion up with shell from redox repository

src/_REDOX

+name=Shell
+icon=file:/ui/mimetypes/application-x-executable-script.bmp
+author=Jeremy Soller
+description=Shell for Redox

src/bin/ion.rs

-extern crate ion;
-
-fn main() {
-    loop {
-        ion::repl()
-    }
-}

src/command.rs

-use std::process::{Command,Output};
-
-pub struct InstructionOut {
-    pub stdout: String,
-    pub stderr: String,
-}
-
-pub fn run(args: &[&str]) -> Option<InstructionOut> {
-    let output: Option<Output>;
-    match args.len() {
-        0 => output = Command::new("").output().ok(),
-        1 => output = Command::new(&args[0]).output().ok(),
-        _ => output = Command::new(&args[0]).args(&args[1..]).output().ok(),
-    }
-    if output.is_some() {
-        let output = output.unwrap();
-        Some(InstructionOut {
-            stdout: String::from_utf8(output.stdout).ok().expect("No stdout"),
-            stderr: String::from_utf8(output.stderr).ok().expect("No stderr"),
-        })
-    } else {
-        None
-    }
-}

src/lib.rs

-#![feature(convert)]
-pub mod command;
-
-use std::io;
-use command::*;
-
-pub fn repl() {
-    let mut input = String::new();
-    match io::stdin().read_line(&mut input) {
-        Ok(_) => {
-            let out_wrap = run(input.trim().split_whitespace().collect::<Vec<&str>>().as_slice());
-            if out_wrap.is_some() {
-                let out = out_wrap.unwrap();
-                if out.stdout.is_empty() {
-                    println!("{}",out.stderr.trim());
-                } else {
-                    println!("{}",out.stdout.trim());
-                }
-            } else {
-                println!("{} is not a valid command", input.trim());
-            }
-        }
-        Err(error) => println!("Line Read Error: {}", error)
-    };
-}

src/to_num.rs

+//! Types convertable to integers
+
+/// Parse the string to a integer using a given radix
+pub trait ToNum {
+    fn to_num_radix(&self, radix: usize) -> usize;
+    fn to_num_radix_signed(&self, radix: usize) -> isize;
+    fn to_num(&self) -> usize;
+    fn to_num_signed(&self) -> isize;
+}
+
+impl ToNum for str {
+    fn to_num_radix(&self, radix: usize) -> usize {
+        if radix == 0 {
+            return 0;
+        }
+
+        let mut num = 0;
+        for c in self.chars() {
+            let digit;
+            if c >= '0' && c <= '9' {
+                digit = c as usize - '0' as usize
+            } else if c >= 'A' && c <= 'Z' {
+                digit = c as usize - 'A' as usize + 10
+            } else if c >= 'a' && c <= 'z' {
+                digit = c as usize - 'a' as usize + 10
+            } else {
+                break;
+            }
+
+            if digit >= radix {
+                break;
+            }
+
+            num *= radix;
+            num += digit;
+        }
+
+        num
+    }
+
+    /// Parse the string as a signed integer using a given radix
+    fn to_num_radix_signed(&self, radix: usize) -> isize {
+        if self.starts_with('-') {
+            -(self[1 ..].to_num_radix(radix) as isize)
+        } else {
+            self.to_num_radix(radix) as isize
+        }
+    }
+
+    /// Parse it as a unsigned integer in base 10
+    fn to_num(&self) -> usize {
+        self.to_num_radix(10)
+    }
+
+    /// Parse it as a signed integer in base 10
+    fn to_num_signed(&self) -> isize {
+        self.to_num_radix_signed(10)
+    }
+}