github.com/demonoid81/moby@v0.0.0-20200517203328-62dd8e17c460/pkg/chrootarchive/diff_windows.go (about)

     1  package chrootarchive // import "github.com/demonoid81/moby/pkg/chrootarchive"
     2  
     3  import (
     4  	"fmt"
     5  	"io"
     6  	"io/ioutil"
     7  	"os"
     8  	"path/filepath"
     9  
    10  	"github.com/demonoid81/moby/pkg/archive"
    11  	"github.com/demonoid81/moby/pkg/longpath"
    12  )
    13  
    14  // applyLayerHandler parses a diff in the standard layer format from `layer`, and
    15  // applies it to the directory `dest`. Returns the size in bytes of the
    16  // contents of the layer.
    17  func applyLayerHandler(dest string, layer io.Reader, options *archive.TarOptions, decompress bool) (size int64, err error) {
    18  	dest = filepath.Clean(dest)
    19  
    20  	// Ensure it is a Windows-style volume path
    21  	dest = longpath.AddPrefix(dest)
    22  
    23  	if decompress {
    24  		decompressed, err := archive.DecompressStream(layer)
    25  		if err != nil {
    26  			return 0, err
    27  		}
    28  		defer decompressed.Close()
    29  
    30  		layer = decompressed
    31  	}
    32  
    33  	tmpDir, err := ioutil.TempDir(os.Getenv("temp"), "temp-docker-extract")
    34  	if err != nil {
    35  		return 0, fmt.Errorf("ApplyLayer failed to create temp-docker-extract under %s. %s", dest, err)
    36  	}
    37  
    38  	s, err := archive.UnpackLayer(dest, layer, nil)
    39  	os.RemoveAll(tmpDir)
    40  	if err != nil {
    41  		return 0, fmt.Errorf("ApplyLayer %s failed UnpackLayer to %s: %s", layer, dest, err)
    42  	}
    43  
    44  	return s, nil
    45  }