Make the 'cat' utility build on Redox

Cargo.lock

@@ -1714,6 +1714,7 @@ dependencies = [
  "data-encoding 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.39 (registry+https://github.com/rust-lang/crates.io-index)",
+ "termion 1.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 

Cargo.toml

@@ -65,7 +65,6 @@ fuchsia = [
 ]
 generic = [
   "arch",
-  "cat",
   "hashsum",
   "hostname",
   "join",
@@ -96,6 +95,7 @@ redox_generic = [
   "base32",
   "base64",
   "basename",
+  "cat",
   "cksum",
   "comm",
   "cp",

src/uucore/Cargo.toml

@@ -9,6 +9,9 @@ time = { version = "0.1.38", optional = true }
 data-encoding = { version = "^1.1", optional = true }
 libc = { version = "0.2.34", optional = true }
 
+[target.'cfg(target_os = "redox")'.dependencies]
+termion = "1.5"
+
 [features]
 fs = ["libc"]
 utf8 = []

src/uucore/fs.rs

@@ -5,12 +5,16 @@
 //
 // For the full copyright and license information, please view the LICENSE
 // file that was distributed with this source code.
-//
+
+#[cfg(target_os = "redox")]
+extern crate termion;
 
 #[cfg(unix)]
 use super::libc;
 use std::env;
 use std::fs;
+#[cfg(target_os = "redox")]
+use std::io;
 use std::io::{Error, ErrorKind};
 use std::io::Result as IOResult;
 use std::path::{Component, Path, PathBuf};
@@ -157,6 +161,11 @@ pub fn is_stdin_interactive() -> bool {
     false
 }
 
+#[cfg(target_os = "redox")]
+pub fn is_stdin_interactive() -> bool {
+    termion::is_tty(&io::stdin())
+}
+
 #[cfg(unix)]
 pub fn is_stdout_interactive() -> bool {
     unsafe { libc::isatty(libc::STDOUT_FILENO) == 1 }
@@ -167,6 +176,11 @@ pub fn is_stdout_interactive() -> bool {
     false
 }
 
+#[cfg(target_os = "redox")]
+pub fn is_stdout_interactive() -> bool {
+    termion::is_tty(&io::stdout())
+}
+
 #[cfg(unix)]
 pub fn is_stderr_interactive() -> bool {
     unsafe { libc::isatty(libc::STDERR_FILENO) == 1 }
@@ -176,3 +190,8 @@ pub fn is_stderr_interactive() -> bool {
 pub fn is_stderr_interactive() -> bool {
     false
 }
+
+#[cfg(target_os = "redox")]
+pub fn is_stderr_interactive() -> bool {
+    termion::is_tty(&io::stderr())
+}