From 5a84c5287040d57b31b6b6d63f9dc938915e80a2 Mon Sep 17 00:00:00 2001
From: bnewbold <bnewbold@robocracy.org>
Date: Sun, 9 Oct 2016 15:37:15 -0700
Subject: more refactoring progress

---
 src/main.rs | 103 +++++++++++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 75 insertions(+), 28 deletions(-)

(limited to 'src')

diff --git a/src/main.rs b/src/main.rs
index 35968ea..c1e06b7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -24,7 +24,9 @@ extern crate log;
 extern crate env_logger;
 extern crate nix;
 extern crate timer;
+extern crate time;
 extern crate chan_signal;
+extern crate uuid;
 
 use std::env;
 use std::u64;
@@ -35,8 +37,11 @@ use std::process::Child;
 use std::net::SocketAddr;
 use std::net::TcpListener;
 use std::net::ToSocketAddrs;
-use std::time::{Duration, Instant};
+use std::time::Instant;
+use time::Duration;
+use std::collections::HashMap;
 use getopts::Options;
+use uuid::Uuid;
 
 use chan_signal::Signal;
 use chan::{Sender, Receiver};
@@ -47,59 +52,99 @@ struct EinConfig {
     retries: u64,
     count: u64,
     bind_fds: Vec<RawFd>,
-    prog: Command,
-    //XXX:rpc_ask: Sender<String>,
-    //XXX:rpc_reply: Receiver<Result<String, String>>,
+    cmd: Command,
+    //TODO:rpc_ask: Sender<String>,
+    //TODO:rpc_reply: Receiver<Result<String, String>>,
 }
 
+#[derive(Copy, Clone, Debug, PartialEq)]
 enum OffspringState {
     Expectant,  // no process exist yet
     Infancy,    // just started, waiting for ACK
     Healthy,
-    Sick,
-    Notified,   // shutting down
+    Notified,   // shutting down gracefully
     Dead,
 }
 
 struct Offspring {
+    id: Uuid,
     state: OffspringState,
     process: Option<Child>,
     birthday: Instant,    // specifies the generation
     attempts: u64,
 }
 
+impl Offspring {
+
+    pub fn new() -> Offspring {
+        Offspring {
+            id: Uuid::new_v4(),
+            state: OffspringState::Expectant,
+            process: None,
+            birthday: Instant::now(),
+            attempts: 0,
+        }
+    }
+
+    pub fn spawn(&mut self, cfg: &mut EinConfig) -> Result<(), String> {
+        if self.state != OffspringState::Expectant && self.state != OffspringState::Dead {
+            return Err(format!("Can't spawn from state: {:?}", self.state));
+        }
+        self.process = Some(cfg.cmd.spawn().expect("error spawning"));
+        self.birthday = Instant::now();
+        self.attempts = 0;
+        Ok(())
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq)]
+enum TimerAction {
+    CheckAlive(Uuid),
+}
+
 // This is the main event loop
 fn shepard(mut cfg: EinConfig, signal_rx: Receiver<Signal>) {
 
-    // birth the initial set of offspring
-
-    // create timer
+    //// create timer
     let timer = timer::Timer::new();
     // XXX: these signatures are bogus
-    let (timer_tx, timer_rx): (Sender<u64>, Receiver<u64>) = chan::async();
+    let (timer_tx, timer_rx): (Sender<TimerAction>, Receiver<TimerAction>) = chan::async();
 
-    // infinite select() loop over timers, signals, rpc
+    //// birth the initial set of offspring
+    let mut brood: HashMap<Uuid, Offspring> = HashMap::new();
+    for _ in 0..cfg.count {
+        println!("Running!");
+        let mut o = Offspring::new();
+        o.spawn(&mut cfg).unwrap();
+        let t_tx = timer_tx.clone();
+        let o_id = o.id.clone();
+        timer.schedule_with_delay(cfg.childhood, move || {
+            t_tx.send(TimerAction::CheckAlive(o_id));
+        });
+        brood.insert(o.id, o);
+    }
 
+    //// infinite select() loop over timers, signals, rpc
     loop {
         chan_select! {
             timer_rx.recv() => println!("Timer tick'd"),
-            signal_rx.recv() => {
-                println!("Signal received!");
+            signal_rx.recv() -> sig => {
+                println!("");
+                println!("Signal received! {:?}", sig);
                 break;
             }
         }
     }
 
-    let mut children: Vec<Child> = vec![];
-    for _ in 0..cfg.count {
-        println!("Running!");
-        children.push(cfg.prog.spawn().expect("error spawning"));
-    }
-
+/* XXX:
     println!("Waiting for all children to die");
-    for mut c in children {
-        c.wait().unwrap();
+    for mut o in brood.values() {
+        match o.process {
+            Some(ref mut p) => { p.wait().unwrap(); () },
+            None => (),
+        }
     }
+*/
     println!("Done.");
 }
 
@@ -133,10 +178,10 @@ fn main() {
     //// Parse Configuration
     let mut cfg = EinConfig{
         count: 1,
-        childhood: Duration::new(3, 0),
+        childhood: Duration::seconds(3),
         retries: 3,
         bind_fds: vec![],
-        prog: Command::new(""),
+        cmd: Command::new(""),
     };
 
     cfg.count = match matches.opt_str("number") {
@@ -167,8 +212,10 @@ fn main() {
         TcpListener::bind(sa).unwrap()
     }).collect();
 
-    let mut prog = Command::new(&program_and_args[0]);
-    prog.args(&program_and_args[1..]);
+    let mut cmd = Command::new(&program_and_args[0]);
+    cmd.args(&program_and_args[1..]);
+
+    // TODO: check that program exists and is executable
 
     cfg.bind_fds = binds.into_iter().map(|b| {
         let orig_fd = b.into_raw_fd();
@@ -178,12 +225,12 @@ fn main() {
         fd
     }).collect();
 
-    prog.env("EINHORN_FD_COUNT", cfg.bind_fds.len().to_string());
+    cmd.env("EINHORN_FD_COUNT", cfg.bind_fds.len().to_string());
     // This iterator destroys the TcpListeners
     for (i, fd) in cfg.bind_fds.iter().enumerate() {
-        prog.env(format!("EINHORN_FD_{}", i), fd.to_string());
+        cmd.env(format!("EINHORN_FD_{}", i), fd.to_string());
     }
-    cfg.prog = prog;
+    cfg.cmd = cmd;
 
     //// Listen for signals (before any fork())
     println!("Registering signal handlers...");
-- 
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