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Diffstat (limited to 'vendor/github.com/Microsoft/hcsshim/internal/wclayer/importlayer.go')
-rw-r--r--vendor/github.com/Microsoft/hcsshim/internal/wclayer/importlayer.go127
1 files changed, 127 insertions, 0 deletions
diff --git a/vendor/github.com/Microsoft/hcsshim/internal/wclayer/importlayer.go b/vendor/github.com/Microsoft/hcsshim/internal/wclayer/importlayer.go
new file mode 100644
index 000000000..486d55470
--- /dev/null
+++ b/vendor/github.com/Microsoft/hcsshim/internal/wclayer/importlayer.go
@@ -0,0 +1,127 @@
+package wclayer
+
+import (
+ "io/ioutil"
+ "os"
+ "path/filepath"
+
+ "github.com/Microsoft/go-winio"
+ "github.com/Microsoft/hcsshim/internal/hcserror"
+ "github.com/Microsoft/hcsshim/internal/safefile"
+ "github.com/sirupsen/logrus"
+)
+
+// ImportLayer will take the contents of the folder at importFolderPath and import
+// that into a layer with the id layerId. Note that in order to correctly populate
+// the layer and interperet the transport format, all parent layers must already
+// be present on the system at the paths provided in parentLayerPaths.
+func ImportLayer(path string, importFolderPath string, parentLayerPaths []string) error {
+ title := "hcsshim::ImportLayer "
+ logrus.Debugf(title+"path %s folder %s", path, importFolderPath)
+
+ // Generate layer descriptors
+ layers, err := layerPathsToDescriptors(parentLayerPaths)
+ if err != nil {
+ return err
+ }
+
+ err = importLayer(&stdDriverInfo, path, importFolderPath, layers)
+ if err != nil {
+ err = hcserror.Errorf(err, title, "path=%s folder=%s", path, importFolderPath)
+ logrus.Error(err)
+ return err
+ }
+
+ logrus.Debugf(title+"succeeded path=%s folder=%s", path, importFolderPath)
+ return nil
+}
+
+// LayerWriter is an interface that supports writing a new container image layer.
+type LayerWriter interface {
+ // Add adds a file to the layer with given metadata.
+ Add(name string, fileInfo *winio.FileBasicInfo) error
+ // AddLink adds a hard link to the layer. The target must already have been added.
+ AddLink(name string, target string) error
+ // Remove removes a file that was present in a parent layer from the layer.
+ Remove(name string) error
+ // Write writes data to the current file. The data must be in the format of a Win32
+ // backup stream.
+ Write(b []byte) (int, error)
+ // Close finishes the layer writing process and releases any resources.
+ Close() error
+}
+
+type legacyLayerWriterWrapper struct {
+ *legacyLayerWriter
+ path string
+ parentLayerPaths []string
+}
+
+func (r *legacyLayerWriterWrapper) Close() error {
+ defer os.RemoveAll(r.root.Name())
+ defer r.legacyLayerWriter.CloseRoots()
+ err := r.legacyLayerWriter.Close()
+ if err != nil {
+ return err
+ }
+
+ if err = ImportLayer(r.destRoot.Name(), r.path, r.parentLayerPaths); err != nil {
+ return err
+ }
+ for _, name := range r.Tombstones {
+ if err = safefile.RemoveRelative(name, r.destRoot); err != nil && !os.IsNotExist(err) {
+ return err
+ }
+ }
+ // Add any hard links that were collected.
+ for _, lnk := range r.PendingLinks {
+ if err = safefile.RemoveRelative(lnk.Path, r.destRoot); err != nil && !os.IsNotExist(err) {
+ return err
+ }
+ if err = safefile.LinkRelative(lnk.Target, lnk.TargetRoot, lnk.Path, r.destRoot); err != nil {
+ return err
+ }
+ }
+ // Prepare the utility VM for use if one is present in the layer.
+ if r.HasUtilityVM {
+ err := safefile.EnsureNotReparsePointRelative("UtilityVM", r.destRoot)
+ if err != nil {
+ return err
+ }
+ err = ProcessUtilityVMImage(filepath.Join(r.destRoot.Name(), "UtilityVM"))
+ if err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+// NewLayerWriter returns a new layer writer for creating a layer on disk.
+// The caller must have taken the SeBackupPrivilege and SeRestorePrivilege privileges
+// to call this and any methods on the resulting LayerWriter.
+func NewLayerWriter(path string, parentLayerPaths []string) (LayerWriter, error) {
+ if len(parentLayerPaths) == 0 {
+ // This is a base layer. It gets imported differently.
+ f, err := safefile.OpenRoot(path)
+ if err != nil {
+ return nil, err
+ }
+ return &baseLayerWriter{
+ root: f,
+ }, nil
+ }
+
+ importPath, err := ioutil.TempDir("", "hcs")
+ if err != nil {
+ return nil, err
+ }
+ w, err := newLegacyLayerWriter(importPath, parentLayerPaths, path)
+ if err != nil {
+ return nil, err
+ }
+ return &legacyLayerWriterWrapper{
+ legacyLayerWriter: w,
+ path: importPath,
+ parentLayerPaths: parentLayerPaths,
+ }, nil
+}