From d859b4b70e620aa1820513094c9575995a91733d Mon Sep 17 00:00:00 2001
From: Matt Green <mattgreenrocks@gmail.com>
Date: Sun, 30 Oct 2016 12:28:11 -0400
Subject: [PATCH] Drop threadpool dep (was spawning threads over and over)

---
 Cargo.lock     |  7 -------
 Cargo.toml     |  1 -
 src/main.rs    |  1 -
 src/process.rs | 33 ++++++++++++++++++---------------
 4 files changed, 18 insertions(+), 24 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index de97888..d425a99 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -12,7 +12,6 @@ dependencies = [
  "mktemp 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "nix 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "notify 2.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "threadpool 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -249,11 +248,6 @@ dependencies = [
  "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "threadpool"
-version = "1.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "time"
 version = "0.1.35"
@@ -350,7 +344,6 @@ dependencies = [
 "checksum semver 0.1.20 (registry+https://github.com/rust-lang/crates.io-index)" = "d4f410fedcf71af0345d7607d246e7ad15faaadd49d240ee3b24e5dc21a820ac"
 "checksum slab 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "d807fd58c4181bbabed77cb3b891ba9748241a552bcc5be698faaebefc54f46e"
 "checksum term_size 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3f7f5f3f71b0040cecc71af239414c23fd3c73570f5ff54cf50e03cef637f2a0"
-"checksum threadpool 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "59f6d3eff89920113dac9db44dde461d71d01e88a5b57b258a0466c32b5d7fe1"
 "checksum time 0.1.35 (registry+https://github.com/rust-lang/crates.io-index)" = "3c7ec6d62a20df54e07ab3b78b9a3932972f4b7981de295563686849eb3989af"
 "checksum unicode-segmentation 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "b905d0fc2a1f0befd86b0e72e31d1787944efef9d38b9358a9e92a69757f7e3b"
 "checksum unicode-width 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2d6722facc10989f63ee0e20a83cd4e1714a9ae11529403ac7e0afd069abc39e"
diff --git a/Cargo.toml b/Cargo.toml
index cfa78dc..841f465 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,7 +19,6 @@ lazy_static = "0.2.1"
 libc = "0.2.16"
 log = "0.3.6"
 notify = "2.6.3"
-threadpool = "1.3.2"
 
 [dev-dependencies]
 mktemp = "0.3.1"
diff --git a/src/main.rs b/src/main.rs
index 19e98f1..5e82756 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,7 +10,6 @@ extern crate log;
 #[macro_use]
 extern crate lazy_static;
 extern crate notify;
-extern crate threadpool;
 
 #[cfg(unix)]
 extern crate nix;
diff --git a/src/process.rs b/src/process.rs
index 1822117..6b95ed4 100644
--- a/src/process.rs
+++ b/src/process.rs
@@ -1,10 +1,9 @@
-use threadpool::ThreadPool;
-
 use std::cell::RefCell;
 use std::collections::{BTreeMap, VecDeque};
 use std::path::{Component, PathBuf};
 use std::rc::Rc;
-use std::sync::mpsc::Sender;
+use std::sync::mpsc::{channel, Receiver, Sender};
+use std::thread;
 
 pub use self::imp::*;
 
@@ -178,26 +177,30 @@ mod imp {
 /// On Windows, we don't have SIGCHLD, and even if we did, we'd still need
 /// to relay that over a channel.
 pub struct ProcessReaper {
-    pool: ThreadPool,
-    tx: Sender<()>,
+    processes_tx: Sender<Process>,
 }
 
 impl ProcessReaper {
     pub fn new(tx: Sender<()>) -> ProcessReaper {
+        let (processes_tx, processes_rx): (Sender<Process>, Receiver<Process>) = channel();
+
+        thread::spawn(move || {
+            loop {
+                while let Ok(mut process) = processes_rx.recv() {
+                    process.wait();
+
+                    let _ = tx.send(());
+                }
+            }
+        });
+
         ProcessReaper {
-            pool: ThreadPool::new(1),
-            tx: tx,
+            processes_tx: processes_tx
         }
     }
 
-    pub fn wait_process(&self, mut process: imp::Process) {
-        let tx = self.tx.clone();
-
-        self.pool.execute(move || {
-            process.wait();
-
-            let _ = tx.send(());
-        });
+    pub fn wait_process(&self, process: imp::Process) {
+        let _ = self.processes_tx.send(process);
     }
 }