Remove dead or redundant code

Signed-off-by: David Gageot <david.gageot@docker.com>

src/cmd/linuxkit/docker/cmd.go

@@ -106,12 +106,7 @@ func Export(container string) (io.ReadCloser, error) {
 	if err != nil {
 		return nil, errors.New("could not initialize Docker API client")
 	}
-	responseBody, err := cli.ContainerExport(context.Background(), container)
+	return cli.ContainerExport(context.Background(), container)
-	if err != nil {
-		return nil, err
-	}
-
-	return responseBody, err
 }
 
 // Save save the provided image ref.

src/cmd/linuxkit/initrd/initrd.go

@@ -2,7 +2,6 @@ package initrd
 
 import (
 	"archive/tar"
-	"bytes"
 	"errors"
 	"io"
 	"path/filepath"
@@ -83,8 +82,9 @@ func copyTarEntry(w *Writer, thdr *tar.Header, r io.Reader) (written int64, err
 	var n int64
 	switch tp {
 	case cpio.TYPE_SYMLINK:
-		buffer := bytes.NewBufferString(thdr.Linkname)
+		var count int
-		n, err = io.Copy(w, buffer)
+		count, err = w.Write([]byte(thdr.Linkname))
+		n = int64(count)
 	case cpio.TYPE_REG:
 		n, err = io.Copy(w, r)
 	}

src/cmd/linuxkit/main.go

@@ -29,18 +29,6 @@ var (
 	Config = GlobalConfig{}
 )
 
-// infoFormatter overrides the default format for Info() log events to
-// provide an easier to read output
-type infoFormatter struct {
-}
-
-func (f *infoFormatter) Format(entry *log.Entry) ([]byte, error) {
-	if entry.Level == log.InfoLevel {
-		return append([]byte(entry.Message), '\n'), nil
-	}
-	return defaultLogFormatter.Format(entry)
-}
-
 func printVersion() {
 	fmt.Printf("%s version %s\n", filepath.Base(os.Args[0]), version.Version)
 	if version.GitCommit != "" {

src/cmd/linuxkit/moby/build.go

@@ -358,8 +358,7 @@ func (k *kernelFilter) WriteHeader(hdr *tar.Header) error {
 		if err := tw.WriteHeader(whdr); err != nil {
 			return err
 		}
-		buf := bytes.NewBufferString(k.cmdline)
+		_, err = tw.Write([]byte(k.cmdline))
-		_, err = io.Copy(tw, buf)
 		if err != nil {
 			return err
 		}

src/cmd/linuxkit/moby/image.go

@@ -2,7 +2,6 @@ package moby
 
 import (
 	"archive/tar"
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -231,8 +230,7 @@ func ImageTar(ref *reference.Spec, prefix string, tw tarWriter, resolv string, o
 				if err := tw.WriteHeader(hdr); err != nil {
 					return err
 				}
-				buf := bytes.NewBufferString(contents)
+				_, err = tw.Write([]byte(contents))
-				_, err = io.Copy(tw, buf)
 				if err != nil {
 					return err
 				}
@@ -307,8 +305,7 @@ func ImageTar(ref *reference.Spec, prefix string, tw tarWriter, resolv string, o
 			return err
 		}
 		if hdr.Size > 0 {
-			buf := bytes.NewBufferString(contents)
+			if _, err = tw.Write([]byte(contents)); err != nil {
-			if _, err = io.Copy(tw, buf); err != nil {
 				return err
 			}
 		}
@@ -349,8 +346,7 @@ func ImageBundle(prefix string, ref *reference.Spec, config []byte, runtime Runt
 	if err := tw.WriteHeader(hdr); err != nil {
 		return err
 	}
-	buf := bytes.NewBuffer(config)
+	if _, err := tw.Write(config); err != nil {
-	if _, err := io.Copy(tw, buf); err != nil {
 		return err
 	}
 
@@ -426,8 +422,7 @@ func ImageBundle(prefix string, ref *reference.Spec, config []byte, runtime Runt
 	if err := tw.WriteHeader(hdr); err != nil {
 		return err
 	}
-	buf = bytes.NewBuffer(runtimeConfig)
+	if _, err := tw.Write(runtimeConfig); err != nil {
-	if _, err := io.Copy(tw, buf); err != nil {
 		return err
 	}
 

src/cmd/linuxkit/moby/schema.go

@@ -1,6 +1,6 @@
 package moby
 
-var schema = string(`
+var schema = `
 {
   "$schema": "http://json-schema.org/draft-04/schema#",
   "title": "Moby Config",
@@ -328,4 +328,4 @@ var schema = string(`
     "files": { "$ref": "#/definitions/files" }
   }
 }
-`)
+`

src/cmd/linuxkit/pkglib/build.go

@@ -24,10 +24,6 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
-const (
-	minimumDockerVersion = "19.03"
-)
-
 type buildOpts struct {
 	skipBuild      bool
 	force          bool

src/cmd/linuxkit/pkglib/docker.go

@@ -42,7 +42,6 @@ import (
 )
 
 const (
-	registryServer        = "https://index.docker.io/v1/"
 	buildkitBuilderName   = "linuxkit-builder"
 	buildkitSocketPath    = "/run/buildkit/buildkitd.sock"
 	buildkitWaitServer    = 30 // seconds
@@ -63,11 +62,6 @@ type dockerRunnerImpl struct {
 	cache bool
 }
 
-type buildContext interface {
-	// Copy copies the build context to the supplied WriterCloser
-	Copy(io.WriteCloser) error
-}
-
 func newDockerRunner(cache bool) dockerRunner {
 	return &dockerRunnerImpl{cache: cache}
 }

src/cmd/linuxkit/pkglib/readerctx.go

@@ -1,18 +0,0 @@
-package pkglib
-
-import (
-	"io"
-)
-
-type readerCtx struct {
-	reader io.Reader
-}
-
-// Copy just copies from reader to writer
-func (c *readerCtx) Copy(w io.WriteCloser) error {
-	_, err := io.Copy(w, c.reader)
-	if err != nil {
-		return err
-	}
-	return w.Close()
-}

src/cmd/linuxkit/run_qemu.go

@@ -113,7 +113,7 @@ func generateMAC() net.HardwareAddr {
 	}
 	mac[0] &^= 0x01 // Clear multicast bit
 	mac[0] |= 0x2   // Set locally administered bit
-	return net.HardwareAddr(mac)
+	return mac
 }
 
 func runQemu(args []string) {
@@ -621,15 +621,3 @@ func buildQemuForwardings(publishFlags multipleFlag) (string, error) {
 
 	return forwardings, nil
 }
-
-func buildDockerForwardings(publishedPorts []string) ([]string, error) {
-	var pmap []string
-	for _, port := range publishedPorts {
-		s, err := NewPublishedPort(port)
-		if err != nil {
-			return nil, err
-		}
-		pmap = append(pmap, "-p", fmt.Sprintf("%d:%d/%s", s.Host, s.Guest, s.Protocol))
-	}
-	return pmap, nil
-}