Use idle timeouts for read and write operations

Thanks to @LukaszMarchewka for making me indirectly aware of the incorret
patch and @jbardin for providing the proper timeout handling.

A connection now will be closed once no read operation success for 30ms
(default value, can be changed).

Fixes #24

cmd/tusd/main.go

@@ -6,6 +6,7 @@ import (
 	"github.com/tus/tusd/filestore"
 	"github.com/tus/tusd/limitedstore"
 	"log"
+	"net"
 	"net/http"
 	"os"
 	"time"
@@ -82,12 +83,74 @@ func main() {
 
 	http.Handle(basepath, http.StripPrefix(basepath, handler))
 
-	server := &http.Server{
-		Addr:        address,
-		ReadTimeout: time.Duration(timeout) * time.Millisecond,
+	timeoutDuration := time.Duration(timeout) * time.Millisecond
+	listener, err := NewListener(address, timeoutDuration, timeoutDuration)
+	if err != nil {
+		stderr.Fatalf("Unable to create listener: %s", err)
 	}
 
-	if err = server.ListenAndServe(); err != nil {
-		stderr.Fatalf("Unable to listen: %s", err)
+	if err = http.Serve(listener, nil); err != nil {
+		stderr.Fatalf("Unable to serve: %s", err)
 	}
 }
+
+// Listener wraps a net.Listener, and gives a place to store the timeout
+// parameters. On Accept, it will wrap the net.Conn with our own Conn for us.
+// Original implementation taken from https://gist.github.com/jbardin/9663312
+// Thanks! <3
+type Listener struct {
+	net.Listener
+	ReadTimeout  time.Duration
+	WriteTimeout time.Duration
+}
+
+func (l *Listener) Accept() (net.Conn, error) {
+	c, err := l.Listener.Accept()
+	if err != nil {
+		return nil, err
+	}
+	tc := &Conn{
+		Conn:         c,
+		ReadTimeout:  l.ReadTimeout,
+		WriteTimeout: l.WriteTimeout,
+	}
+	return tc, nil
+}
+
+// Conn wraps a net.Conn, and sets a deadline for every read
+// and write operation.
+type Conn struct {
+	net.Conn
+	ReadTimeout  time.Duration
+	WriteTimeout time.Duration
+}
+
+func (c *Conn) Read(b []byte) (int, error) {
+	err := c.Conn.SetReadDeadline(time.Now().Add(c.ReadTimeout))
+	if err != nil {
+		return 0, err
+	}
+	return c.Conn.Read(b)
+}
+
+func (c *Conn) Write(b []byte) (int, error) {
+	err := c.Conn.SetWriteDeadline(time.Now().Add(c.WriteTimeout))
+	if err != nil {
+		return 0, err
+	}
+	return c.Conn.Write(b)
+}
+
+func NewListener(addr string, readTimeout, writeTimeout time.Duration) (net.Listener, error) {
+	l, err := net.Listen("tcp", addr)
+	if err != nil {
+		return nil, err
+	}
+
+	tl := &Listener{
+		Listener:     l,
+		ReadTimeout:  readTimeout,
+		WriteTimeout: writeTimeout,
+	}
+	return tl, nil
+}