@@ -18,6 +18,7 @@ import (

 	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/pkg/log"

 	"github.com/docker/docker/pkg/system"

 	"github.com/docker/docker/utils"

@@ -107,7 +108,7 @@ func CompressStream(dest io.WriteCloser, compression Compression) (io.WriteClose

 	switch compression {

 	case Uncompressed:

-		return utils.NopWriteCloser(dest), nil

+		return ioutils.NopWriteCloser(dest), nil

 	case Gzip:

 		return gzip.NewWriter(dest), nil

 	case Bzip2, Xz:

@@ -8,6 +8,7 @@ import (

 	"time"

 	"github.com/docker/docker/engine"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/pkg/jsonlog"

 	"github.com/docker/docker/pkg/log"

 	"github.com/docker/docker/utils"

@@ -195,7 +196,7 @@ func (daemon *Daemon) Attach(container *Container, stdin io.ReadCloser, stdinClo

 			if cStdout, err := container.StdoutPipe(); err != nil {

 				log.Errorf("attach: stdout pipe: %s", err)

 			} else {

-				io.Copy(&utils.NopWriter{}, cStdout)

+				io.Copy(&ioutils.NopWriter{}, cStdout)

 			}

 		}()

 	}

@@ -234,7 +235,7 @@ func (daemon *Daemon) Attach(container *Container, stdin io.ReadCloser, stdinClo

 			if cStderr, err := container.StderrPipe(); err != nil {

 				log.Errorf("attach: stdout pipe: %s", err)

 			} else {

-				io.Copy(&utils.NopWriter{}, cStderr)

+				io.Copy(&ioutils.NopWriter{}, cStderr)

 			}

 		}()

 	}

@@ -24,6 +24,7 @@ import (

 	"github.com/docker/docker/links"

 	"github.com/docker/docker/nat"

 	"github.com/docker/docker/pkg/broadcastwriter"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/pkg/log"

 	"github.com/docker/docker/pkg/networkfs/etchosts"

 	"github.com/docker/docker/pkg/networkfs/resolvconf"

@@ -366,25 +367,25 @@ func (streamConfig *StreamConfig) StdinPipe() (io.WriteCloser, error) {

 func (streamConfig *StreamConfig) StdoutPipe() (io.ReadCloser, error) {

 	reader, writer := io.Pipe()

 	streamConfig.stdout.AddWriter(writer, "")

-	return utils.NewBufReader(reader), nil

+	return ioutils.NewBufReader(reader), nil

 }

 func (streamConfig *StreamConfig) StderrPipe() (io.ReadCloser, error) {

 	reader, writer := io.Pipe()

 	streamConfig.stderr.AddWriter(writer, "")

-	return utils.NewBufReader(reader), nil

+	return ioutils.NewBufReader(reader), nil

 }

 func (streamConfig *StreamConfig) StdoutLogPipe() io.ReadCloser {

 	reader, writer := io.Pipe()

 	streamConfig.stdout.AddWriter(writer, "stdout")

-	return utils.NewBufReader(reader)

+	return ioutils.NewBufReader(reader)

 }

 func (streamConfig *StreamConfig) StderrLogPipe() io.ReadCloser {

 	reader, writer := io.Pipe()

 	streamConfig.stderr.AddWriter(writer, "stderr")

-	return utils.NewBufReader(reader)

+	return ioutils.NewBufReader(reader)

 }

 func (container *Container) buildHostnameFile() error {

@@ -655,7 +656,7 @@ func (container *Container) ExportRw() (archive.Archive, error) {

 		container.Unmount()

 		return nil, err

 	}

-	return utils.NewReadCloserWrapper(archive, func() error {

+	return ioutils.NewReadCloserWrapper(archive, func() error {

 			err := archive.Close()

 			container.Unmount()

 			return err

@@ -673,7 +674,7 @@ func (container *Container) Export() (archive.Archive, error) {

 		container.Unmount()

 		return nil, err

 	}

-	return utils.NewReadCloserWrapper(archive, func() error {

+	return ioutils.NewReadCloserWrapper(archive, func() error {

 			err := archive.Close()

 			container.Unmount()

 			return err

@@ -809,7 +810,7 @@ func (container *Container) Copy(resource string) (io.ReadCloser, error) {

 		container.Unmount()

 		return nil, err

 	}

-	return utils.NewReadCloserWrapper(archive, func() error {

+	return ioutils.NewReadCloserWrapper(archive, func() error {

 			err := archive.Close()

 			container.Unmount()

 			return err

@@ -28,6 +28,7 @@ import (

 	"github.com/docker/docker/image"

 	"github.com/docker/docker/pkg/broadcastwriter"

 	"github.com/docker/docker/pkg/graphdb"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/pkg/log"

 	"github.com/docker/docker/pkg/namesgenerator"

 	"github.com/docker/docker/pkg/networkfs/resolvconf"

@@ -201,7 +202,7 @@ func (daemon *Daemon) register(container *Container, updateSuffixarray bool) err

 	if container.Config.OpenStdin {

 		container.stdin, container.stdinPipe = io.Pipe()

 	} else {

-		container.stdinPipe = utils.NopWriteCloser(ioutil.Discard) // Silently drop stdin

+		container.stdinPipe = ioutils.NopWriteCloser(ioutil.Discard) // Silently drop stdin

 	}

 	// done

 	daemon.containers.Add(container.ID, container)

@@ -965,7 +966,7 @@ func (daemon *Daemon) Diff(container *Container) (archive.Archive, error) {

 	if err != nil {

 		return nil, err

 	}

-	return utils.NewReadCloserWrapper(archive, func() error {

+	return ioutils.NewReadCloserWrapper(archive, func() error {

 		err := archive.Close()

 		daemon.driver.Put(container.ID)

 		return err

@@ -10,6 +10,7 @@ import (

 	"sync"

 	"time"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/utils"

 )

@@ -123,7 +124,7 @@ func (eng *Engine) Job(name string, args ...string) *Job {

 		env:    &Env{},

 	}

 	if eng.Logging {

-		job.Stderr.Add(utils.NopWriteCloser(eng.Stderr))

+		job.Stderr.Add(ioutils.NopWriteCloser(eng.Stderr))

 	}

 	// Catchall is shadowed by specific Register.

@@ -11,6 +11,7 @@ import (

 	"github.com/docker/docker/archive"

 	"github.com/docker/docker/daemon/graphdriver"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/pkg/log"

 	"github.com/docker/docker/runconfig"

 	"github.com/docker/docker/utils"

@@ -198,7 +199,7 @@ func (img *Image) TarLayer() (arch archive.Archive, err error) {

 		if err != nil {

 			return nil, err

 		}

-		return utils.NewReadCloserWrapper(archive, func() error {

+		return ioutils.NewReadCloserWrapper(archive, func() error {

 			err := archive.Close()

 			driver.Put(img.ID)

 			return err

@@ -218,7 +219,7 @@ func (img *Image) TarLayer() (arch archive.Archive, err error) {

 	if err != nil {

 		return nil, err

 	}

-	return utils.NewReadCloserWrapper(archive, func() error {

+	return ioutils.NewReadCloserWrapper(archive, func() error {

 		err := archive.Close()

 		driver.Put(img.ID)

 		return err

@@ -20,6 +20,7 @@ import (

 	"github.com/docker/docker/engine"

 	"github.com/docker/docker/image"

 	"github.com/docker/docker/nat"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/pkg/log"

 	"github.com/docker/docker/reexec"

 	"github.com/docker/docker/runconfig"

@@ -141,7 +142,7 @@ func setupBaseImage() {

 	if err := job.Run(); err != nil || img.Get("Id") != unitTestImageID {

 		// Retrieve the Image

 		job = eng.Job("pull", unitTestImageName)

-		job.Stdout.Add(utils.NopWriteCloser(os.Stdout))

+		job.Stdout.Add(ioutils.NopWriteCloser(os.Stdout))

 		if err := job.Run(); err != nil {

 			log.Fatalf("Unable to pull the test image: %s", err)

 		}

new file mode 100644

@@ -0,0 +1,82 @@

+package ioutils

+

+import (

+	"bytes"

+	"io"

+	"sync"

+)

+

+type readCloserWrapper struct {

+	io.Reader

+	closer func() error

+}

+

+func (r *readCloserWrapper) Close() error {

+	return r.closer()

+}

+

+func NewReadCloserWrapper(r io.Reader, closer func() error) io.ReadCloser {

+	return &readCloserWrapper{

+		Reader: r,

+		closer: closer,

+	}

+}

+

+type bufReader struct {

+	sync.Mutex

+	buf    *bytes.Buffer

+	reader io.Reader

+	err    error

+	wait   sync.Cond

+}

+

+func NewBufReader(r io.Reader) *bufReader {

+	reader := &bufReader{

+		buf:    &bytes.Buffer{},

+		reader: r,

+	}

+	reader.wait.L = &reader.Mutex

+	go reader.drain()

+	return reader

+}

+

+func (r *bufReader) drain() {

+	buf := make([]byte, 1024)

+	for {

+		n, err := r.reader.Read(buf)

+		r.Lock()

+		if err != nil {

+			r.err = err

+		} else {

+			r.buf.Write(buf[0:n])

+		}

+		r.wait.Signal()

+		r.Unlock()

+		if err != nil {

+			break

+		}

+	}

+}

+

+func (r *bufReader) Read(p []byte) (n int, err error) {

+	r.Lock()

+	defer r.Unlock()

+	for {

+		n, err = r.buf.Read(p)

+		if n > 0 {

+			return n, err

+		}

+		if r.err != nil {

+			return 0, r.err

+		}

+		r.wait.Wait()

+	}

+}

+

+func (r *bufReader) Close() error {

+	closer, ok := r.reader.(io.ReadCloser)

+	if !ok {

+		return nil

+	}

+	return closer.Close()

+}

new file mode 100644

@@ -0,0 +1,34 @@

+package ioutils

+

+import (

+	"bytes"

+	"io"

+	"io/ioutil"

+	"testing"

+)

+

+func TestBufReader(t *testing.T) {

+	reader, writer := io.Pipe()

+	bufreader := NewBufReader(reader)

+

+	// Write everything down to a Pipe

+	// Usually, a pipe should block but because of the buffered reader,

+	// the writes will go through

+	done := make(chan bool)

+	go func() {

+		writer.Write([]byte("hello world"))

+		writer.Close()

+		done <- true

+	}()

+

+	// Drain the reader *after* everything has been written, just to verify

+	// it is indeed buffering

+	<-done

+	output, err := ioutil.ReadAll(bufreader)

+	if err != nil {

+		t.Fatal(err)

+	}

+	if !bytes.Equal(output, []byte("hello world")) {

+		t.Error(string(output))

+	}

+}

new file mode 100644

@@ -0,0 +1,23 @@

+package ioutils

+

+import "io"

+

+type NopWriter struct{}

+

+func (*NopWriter) Write(buf []byte) (int, error) {

+	return len(buf), nil

+}

+

+type nopWriteCloser struct {

+	io.Writer

+}

+

+func (w *nopWriteCloser) Close() error { return nil }

+

+func NopWriteCloser(w io.Writer) io.WriteCloser {

+	return &nopWriteCloser{w}

+}

+

+type NopFlusher struct{}

+

+func (f *NopFlusher) Flush() {}

@@ -20,6 +20,7 @@ import (

 	"syscall"

 	"github.com/docker/docker/dockerversion"

+	"github.com/docker/docker/pkg/ioutils"

 	"github.com/docker/docker/pkg/log"

 )

@@ -157,81 +158,6 @@ func DockerInitPath(localCopy string) string {

 	return ""

 }

-type NopWriter struct{}

-

-func (*NopWriter) Write(buf []byte) (int, error) {

-	return len(buf), nil

-}

-

-type nopWriteCloser struct {

-	io.Writer

-}

-

-func (w *nopWriteCloser) Close() error { return nil }

-

-func NopWriteCloser(w io.Writer) io.WriteCloser {

-	return &nopWriteCloser{w}

-}

-

-type bufReader struct {

-	sync.Mutex

-	buf    *bytes.Buffer

-	reader io.Reader

-	err    error

-	wait   sync.Cond

-}

-

-func NewBufReader(r io.Reader) *bufReader {

-	reader := &bufReader{

-		buf:    &bytes.Buffer{},

-		reader: r,

-	}

-	reader.wait.L = &reader.Mutex

-	go reader.drain()

-	return reader

-}

-

-func (r *bufReader) drain() {

-	buf := make([]byte, 1024)

-	for {

-		n, err := r.reader.Read(buf)

-		r.Lock()

-		if err != nil {

-			r.err = err

-		} else {

-			r.buf.Write(buf[0:n])

-		}

-		r.wait.Signal()

-		r.Unlock()

-		if err != nil {

-			break

-		}

-	}

-}

-

-func (r *bufReader) Read(p []byte) (n int, err error) {

-	r.Lock()

-	defer r.Unlock()

-	for {

-		n, err = r.buf.Read(p)

-		if n > 0 {

-			return n, err

-		}

-		if r.err != nil {

-			return 0, r.err

-		}

-		r.wait.Wait()

-	}

-}

-

-func (r *bufReader) Close() error {

-	closer, ok := r.reader.(io.ReadCloser)

-	if !ok {

-		return nil

-	}

-	return closer.Close()

-}

-

 func GetTotalUsedFds() int {

 	if fds, err := ioutil.ReadDir(fmt.Sprintf("/proc/%d/fd", os.Getpid())); err != nil {

 		log.Errorf("Error opening /proc/%d/fd: %s", os.Getpid(), err)

@@ -340,10 +266,6 @@ func CopyDirectory(source, dest string) error {

 	return nil

 }

-type NopFlusher struct{}

-

-func (f *NopFlusher) Flush() {}

-

 type WriteFlusher struct {

 	sync.Mutex

 	w       io.Writer

@@ -370,7 +292,7 @@ func NewWriteFlusher(w io.Writer) *WriteFlusher {

 	if f, ok := w.(http.Flusher); ok {

 		flusher = f

 	} else {

-		flusher = &NopFlusher{}

+		flusher = &ioutils.NopFlusher{}

 	}

 	return &WriteFlusher{w: w, flusher: flusher}

 }

@@ -527,22 +449,6 @@ func CopyFile(src, dst string) (int64, error) {

 	return io.Copy(df, sf)

 }

-type readCloserWrapper struct {

-	io.Reader

-	closer func() error

-}

-

-func (r *readCloserWrapper) Close() error {

-	return r.closer()

-}

-

-func NewReadCloserWrapper(r io.Reader, closer func() error) io.ReadCloser {

-	return &readCloserWrapper{

-		Reader: r,

-		closer: closer,

-	}

-}

-

 // ReplaceOrAppendValues returns the defaults with the overrides either

 // replaced by env key or appended to the list

 func ReplaceOrAppendEnvValues(defaults, overrides []string) []string {

@@ -1,39 +1,10 @@

 package utils

 import (

-	"bytes"

-	"io"

-	"io/ioutil"

 	"os"

 	"testing"

 )

-func TestBufReader(t *testing.T) {

-	reader, writer := io.Pipe()

-	bufreader := NewBufReader(reader)

-

-	// Write everything down to a Pipe

-	// Usually, a pipe should block but because of the buffered reader,

-	// the writes will go through

-	done := make(chan bool)

-	go func() {

-		writer.Write([]byte("hello world"))

-		writer.Close()

-		done <- true

-	}()

-

-	// Drain the reader *after* everything has been written, just to verify

-	// it is indeed buffering

-	<-done

-	output, err := ioutil.ReadAll(bufreader)

-	if err != nil {

-		t.Fatal(err)

-	}

-	if !bytes.Equal(output, []byte("hello world")) {

-		t.Error(string(output))

-	}

-}

-

 func TestCheckLocalDns(t *testing.T) {

 	for resolv, result := range map[string]bool{`# Dynamic

 nameserver 10.0.2.3