Change to a bounded channel

Cargo.toml

 [package]
 name = "hashtoc"
-version = "0.1.4"
+version = "0.1.5"
 authors = ["Anders Blomdell <anders.blomdell@control.lth.se>"]
 build = "build.rs"
 links = "libhash.a,libssl"

src/main.rs

@@ -29,7 +29,7 @@ use std::ffi::OsStr;
 use std::os::unix::ffi::OsStrExt;
 use std::fs::{Metadata};
 use std::path::{Path, PathBuf};
-use std::sync::mpsc::{channel, Receiver, Sender};
+use std::sync::mpsc::{sync_channel, Receiver, SyncSender};
 use std::thread;
 use std::fmt;
 use std::process::exit;
@@ -178,7 +178,7 @@ struct WorkerPool<T> {
     pool: ThreadPool,
     pending: usize,
     rx: Receiver<T>,
-    tx: Sender<T>
+    tx: SyncSender<T>
 }
 
 /*trait ExecuteIf {
@@ -192,7 +192,7 @@ impl ExecuteIf for WorkerPool {
  */
 impl<T> WorkerPool<T> {
     fn new(jobs: usize) -> WorkerPool<T> {
-        let (tx, rx) = channel::<T>();
+        let (tx, rx) = sync_channel::<T>(jobs * 2);
         WorkerPool {
             pool: ThreadPool::new(jobs),
             pending: 0,
@@ -626,9 +626,9 @@ fn main() -> std::io::Result<()> {
              .index(1))
         .get_matches();
 
-
     let (worker, tx) = {
-        let (tx, rx) = channel();
+        let jobs = option_t_or_exit!(matches, "jobs", usize).unwrap_or(1);
+        let (tx, rx) = sync_channel(jobs * 2);
         let args = matches.clone();
         let worker = thread::spawn(move|| { dispatcher(args, rx); });
         (worker, tx)