github.com/containers/storage v1.12.13

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

vendor/github.com/containers/storage/pkg/tarlog/tarlogger.go

@@ -0,0 +1,47 @@
+package tarlog
+
+import (
+	"archive/tar"
+	"io"
+	"os"
+	"sync"
+
+	"github.com/pkg/errors"
+)
+
+type tarLogger struct {
+	writer *os.File
+	wg     sync.WaitGroup
+}
+
+// NewLogger returns a writer that, when a tar archive is written to it, calls
+// `logger` for each file header it encounters in the archive.
+func NewLogger(logger func(*tar.Header)) (io.WriteCloser, error) {
+	reader, writer, err := os.Pipe()
+	if err != nil {
+		return nil, errors.Wrapf(err, "error creating pipe for tar logger")
+	}
+	t := &tarLogger{writer: writer}
+	tr := tar.NewReader(reader)
+	t.wg.Add(1)
+	go func() {
+		hdr, err := tr.Next()
+		for err == nil {
+			logger(hdr)
+			hdr, err = tr.Next()
+		}
+		reader.Close()
+		t.wg.Done()
+	}()
+	return t, nil
+}
+
+func (t *tarLogger) Write(b []byte) (int, error) {
+	return t.writer.Write(b)
+}
+
+func (t *tarLogger) Close() error {
+	err := t.writer.Close()
+	t.wg.Wait()
+	return err
+}