Fix invalid argument error on push

pkg/archive/archive.go

@@ -771,20 +771,33 @@ func NewTempArchive(src Archive, dir string) (*TempArchive, error) {
 		return nil, err
 	}
 	size := st.Size()
-	return &TempArchive{f, size, 0}, nil
+	return &TempArchive{File: f, Size: size}, nil
 }
 
 type TempArchive struct {
 	*os.File
-	Size int64 // Pre-computed from Stat().Size() as a convenience
-	read int64
+	Size   int64 // Pre-computed from Stat().Size() as a convenience
+	read   int64
+	closed bool
+}
+
+// Close closes the underlying file if it's still open, or does a no-op
+// to allow callers to try to close the TempArchive multiple times safely.
+func (archive *TempArchive) Close() error {
+	if archive.closed {
+		return nil
+	}
+
+	archive.closed = true
+
+	return archive.File.Close()
 }
 
 func (archive *TempArchive) Read(data []byte) (int, error) {
 	n, err := archive.File.Read(data)
 	archive.read += int64(n)
 	if err != nil || archive.read == archive.Size {
-		archive.File.Close()
+		archive.Close()
 		os.Remove(archive.File.Name())
 	}
 	return n, err

pkg/archive/archive_test.go

@@ -9,6 +9,7 @@ import (
 	"os/exec"
 	"path"
 	"path/filepath"
+	"strings"
 	"syscall"
 	"testing"
 	"time"
@@ -607,3 +608,18 @@ func TestUntarInvalidSymlink(t *testing.T) {
 		}
 	}
 }
+
+func TestTempArchiveCloseMultipleTimes(t *testing.T) {
+	reader := ioutil.NopCloser(strings.NewReader("hello"))
+	tempArchive, err := NewTempArchive(reader, "")
+	buf := make([]byte, 10)
+	n, err := tempArchive.Read(buf)
+	if n != 5 {
+		t.Fatalf("Expected to read 5 bytes. Read %d instead", n)
+	}
+	for i := 0; i < 3; i++ {
+		if err = tempArchive.Close(); err != nil {
+			t.Fatalf("i=%d. Unexpected error closing temp archive: %v", i, err)
+		}
+	}
+}