container: add additional child process for task submission handling

The parent process will be used for process reaping and signal handling.

1 files changed, 13 insertions, 3 deletions

diff --git a/src/runner/container/mod.rs b/src/runner/container/mod.rs
index 2b00791..a839ae2 100644
--- a/src/runner/container/mod.rs
+++ b/src/runner/container/mod.rs
@@ -9,7 +9,7 @@ use capctl::prctl;
 use ipc_channel::ipc;
 use nix::{
 	sched::CloneFlags,
-	sys::{signal, stat},
+	sys::{signal, stat, wait},
 	unistd::{self, Gid, Uid},
 };
 use serde::{Deserialize, Serialize};
@@ -64,9 +64,19 @@ fn runner(uid: Uid, gid: Gid, channel: ipc::IpcReceiver<Message>) -> ! {
 
 	init::init_runner().unwrap();
 
-	unsafe { signal::signal(signal::Signal::SIGCHLD, signal::SigHandler::SigIgn) }.unwrap();
+	let msg_handler = match unsafe { unistd::fork() }.expect("fork()") {
+		unistd::ForkResult::Parent { child } => {
+			drop(channel);
+			child
+		}
+		unistd::ForkResult::Child => {
+			unsafe { signal::signal(signal::Signal::SIGCHLD, signal::SigHandler::SigIgn) }.unwrap();
+			runner_loop(channel);
+			process::exit(0);
+		}
+	};
 
-	runner_loop(channel);
+	wait::waitpid(msg_handler, None).expect("waitpid()");
 
 	process::exit(0);
 }