archive: regularize some naming

* tarAppender did not append to tar files

* createTarFile did not create tar files

* addTarFile did not add tar files

Signed-off-by: Han-Wen Nienhuys <[email protected]>

pkg/archive/archive.go

@@ -179,6 +179,7 @@ func DecompressStream(archive io.Reader) (_ io.ReadCloser, Err error) {
 
 	defer func() {
 		if Err != nil {
+			// In the normal case, the buffer is embedded in the ReadCloser return.
 			p.Put(buf)
 		}
 	}()
@@ -475,7 +476,7 @@ type TarWhiteoutConverter interface {
 	ConvertReadWithHandler(*tar.Header, string, TarWhiteoutHandler) (bool, error)
 }
 
-type tarAppender struct {
+type tarWriter struct {
 	TarWriter *tar.Writer
 	Buffer    *bufio.Writer
 
@@ -496,8 +497,8 @@ type tarAppender struct {
 	CopyPass bool
 }
 
-func newTarAppender(idMapping *idtools.IDMappings, writer io.Writer, chownOpts *idtools.IDPair) *tarAppender {
-	return &tarAppender{
+func newTarWriter(idMapping *idtools.IDMappings, writer io.Writer, chownOpts *idtools.IDPair) *tarWriter {
+	return &tarWriter{
 		SeenFiles:  make(map[uint64]string),
 		TarWriter:  tar.NewWriter(writer),
 		Buffer:     pools.BufioWriter32KPool.Get(nil),
@@ -521,8 +522,8 @@ func canonicalTarName(name string, isDir bool) (string, error) {
 	return name, nil
 }
 
-// addTarFile adds to the tar archive a file from `path` as `name`
-func (ta *tarAppender) addTarFile(path, name string) error {
+// addFile adds a file from `path` as `name` to the tar archive.
+func (ta *tarWriter) addFile(path, name string) error {
 	fi, err := os.Lstat(path)
 	if err != nil {
 		return err
@@ -650,7 +651,7 @@ func (ta *tarAppender) addTarFile(path, name string) error {
 	return nil
 }
 
-func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader, Lchown bool, chownOpts *idtools.IDPair, inUserns, ignoreChownErrors bool, forceMask *os.FileMode, buffer []byte) error {
+func extractTarFileEntry(path, extractDir string, hdr *tar.Header, reader io.Reader, Lchown bool, chownOpts *idtools.IDPair, inUserns, ignoreChownErrors bool, forceMask *os.FileMode, buffer []byte) error {
 	// hdr.Mode is in linux format, which we can use for sycalls,
 	// but for os.Foo() calls we need the mode converted to os.FileMode,
 	// so use hdrInfo.Mode() (they differ for e.g. setuid bits)
@@ -862,7 +863,7 @@ func TarWithOptions(srcPath string, options *TarOptions) (io.ReadCloser, error)
 	}
 
 	go func() {
-		ta := newTarAppender(
+		ta := newTarWriter(
 			idtools.NewIDMappingsFromMaps(options.UIDMaps, options.GIDMaps),
 			compressWriter,
 			options.ChownOpts,
@@ -1002,7 +1003,7 @@ func TarWithOptions(srcPath string, options *TarOptions) (io.ReadCloser, error)
 					relFilePath = strings.Replace(relFilePath, include, replacement, 1)
 				}
 
-				if err := ta.addTarFile(filePath, relFilePath); err != nil {
+				if err := ta.addFile(filePath, relFilePath); err != nil {
 					logrus.Errorf("Can't add file %s to tar: %s", filePath, err)
 					// if pipe is broken, stop writing tar stream to it
 					if err == io.ErrClosedPipe {
@@ -1137,7 +1138,7 @@ loop:
 			chownOpts = &idtools.IDPair{UID: hdr.Uid, GID: hdr.Gid}
 		}
 
-		if err = createTarFile(path, dest, hdr, trBuf, doChown, chownOpts, options.InUserNS, options.IgnoreChownErrors, options.ForceMask, buffer); err != nil {
+		if err = extractTarFileEntry(path, dest, hdr, trBuf, doChown, chownOpts, options.InUserNS, options.IgnoreChownErrors, options.ForceMask, buffer); err != nil {
 			return err
 		}
 

pkg/archive/archive_test.go

@@ -771,7 +771,7 @@ func TestTypeXGlobalHeaderDoesNotFail(t *testing.T) {
 	hdr := tar.Header{Typeflag: tar.TypeXGlobalHeader}
 	tmpDir := t.TempDir()
 	buffer := make([]byte, 1<<20)
-	err := createTarFile(filepath.Join(tmpDir, "pax_global_header"), tmpDir, &hdr, nil, true, nil, false, false, nil, buffer)
+	err := extractTarFileEntry(filepath.Join(tmpDir, "pax_global_header"), tmpDir, &hdr, nil, true, nil, false, false, nil, buffer)
 	if err != nil {
 		t.Fatal(err)
 	}

pkg/archive/changes.go

@@ -452,7 +452,7 @@ func ChangesSize(newDir string, changes []Change) int64 {
 func ExportChanges(dir string, changes []Change, uidMaps, gidMaps []idtools.IDMap) (io.ReadCloser, error) {
 	reader, writer := io.Pipe()
 	go func() {
-		ta := newTarAppender(idtools.NewIDMappingsFromMaps(uidMaps, gidMaps), writer, nil)
+		ta := newTarWriter(idtools.NewIDMappingsFromMaps(uidMaps, gidMaps), writer, nil)
 
 		// this buffer is needed for the duration of this piped stream
 		defer pools.BufioWriter32KPool.Put(ta.Buffer)
@@ -481,7 +481,7 @@ func ExportChanges(dir string, changes []Change, uidMaps, gidMaps []idtools.IDMa
 				}
 			} else {
 				path := filepath.Join(dir, change.Path)
-				if err := ta.addTarFile(path, change.Path[1:]); err != nil {
+				if err := ta.addFile(path, change.Path[1:]); err != nil {
 					logrus.Debugf("Can't add file %s to tar: %s", path, err)
 				}
 			}

pkg/archive/diff.go

@@ -107,7 +107,7 @@ func UnpackLayer(dest string, layer io.Reader, options *TarOptions) (size int64,
 					}
 					defer os.RemoveAll(aufsTempdir)
 				}
-				if err := createTarFile(filepath.Join(aufsTempdir, basename), dest, hdr, tr, true, nil, options.InUserNS, options.IgnoreChownErrors, options.ForceMask, buffer); err != nil {
+				if err := extractTarFileEntry(filepath.Join(aufsTempdir, basename), dest, hdr, tr, true, nil, options.InUserNS, options.IgnoreChownErrors, options.ForceMask, buffer); err != nil {
 					return 0, err
 				}
 			}
@@ -176,7 +176,7 @@ func UnpackLayer(dest string, layer io.Reader, options *TarOptions) (size int64,
 			// We always reset the immutable flag (if present) to allow metadata
 			// changes and to allow directory modification. The flag will be
 			// re-applied based on the contents of hdr either at the end for
-			// directories or in createTarFile otherwise.
+			// directories or in extractTarFileEntry otherwise.
 			if fi, err := os.Lstat(path); err == nil {
 				if err := resetImmutable(path, &fi); err != nil {
 					return 0, err
@@ -212,7 +212,7 @@ func UnpackLayer(dest string, layer io.Reader, options *TarOptions) (size int64,
 				return 0, err
 			}
 
-			if err := createTarFile(path, dest, srcHdr, srcData, true, nil, options.InUserNS, options.IgnoreChownErrors, options.ForceMask, buffer); err != nil {
+			if err := extractTarFileEntry(path, dest, srcHdr, srcData, true, nil, options.InUserNS, options.IgnoreChownErrors, options.ForceMask, buffer); err != nil {
 				return 0, err
 			}