implement a simple shell in linux using nix

Cargo.toml

@@ -8,7 +8,8 @@ repository = "https://github.com/droundy/bigbro"
 documentation = "https://droundy.github.io/bigbro"
 
 [dependencies]
-nix = "0.4"
+# nix = "0.4"
+nix = { git = "https://github.com/carllerche/nix-rust" }
 libc = "*"
 
 [dev-dependencies]

src/lib.rs

@@ -2,6 +2,8 @@
 //!
 //! This allows you to track file accesses by child processes.
 
+extern crate nix;
+
 use std::path;
 use std::collections::HashSet;
 
@@ -31,7 +33,7 @@ mod linux;
 pub use linux::shell;
 
 #[cfg(not(target_os = "linux"))]
-pub fn shell(command_line: &str) -> io::Result<Accesses> {
+pub fn shell(command_line: &str) -> Result<Accesses, Box<Error>> {
     let r = try!(try!(process::Command::new("sh").arg("-c")
                       .arg(command_line).spawn()).wait());
     Ok(Accesses {

src/linux.rs

@@ -1,16 +1,51 @@
-use super::{Accesses, ExitStatus};
 
-use std::process;
-use std::collections::HashSet;
-use std::io;
+use super::{Accesses};
 
+use std::io;
+use nix;
+use std::ffi::{CString};
+use std::collections::HashSet;
 
 pub fn shell(command_line: &str) -> io::Result<Accesses> {
-    let r = try!(try!(process::Command::new("sh").arg("-c")
-                      .arg(command_line).spawn()).wait());
-    Ok(Accesses {
-        status: ExitStatus { exit_code: r.code() },
-        read_files: HashSet::new(),
-        wrote_files: HashSet::new(),
-    })
+    match try!(nix::unistd::fork()) {
+        nix::unistd::Fork::Parent(pid) => {
+            use nix::sys::wait::WaitStatus::*;
+            use super::ExitStatus;
+            println!("I am parent of {}", pid);
+            match try!(nix::sys::wait::waitpid(pid, None)) {
+                Exited(_,ii) => {
+                    Ok(Accesses {
+                        status: ExitStatus { exit_code: Some(ii as i32) },
+                        read_files: HashSet::new(),
+                        wrote_files: HashSet::new(),
+                    })
+                },
+                Signaled(_,_,_) => {
+                    Ok(Accesses {
+                        status: ExitStatus { exit_code: None },
+                        read_files: HashSet::new(),
+                        wrote_files: HashSet::new(),
+                    })
+                },
+                Stopped(_,_) => unreachable!(),
+                Continued(_) => unreachable!(),
+                StillAlive => unreachable!(),
+            }
+        },
+        nix::unistd::Fork::Child => {
+            println!("Hello world");
+            nix::unistd::execvp(&CString::new("sh").unwrap(),
+                                &[CString::new("sh").unwrap(),
+                                  CString::new("-c").unwrap(),
+                                  CString::new(command_line).unwrap()]);
+            unreachable!()
+        },
+    }
+}
+
+#[test]
+fn test_into_io_error() {
+    use nix::errno::Errno;
+    use std;
+    std::io::Error::from(nix::Error::InvalidPath);
 }