diff options
Diffstat (limited to 'vendor/github.com/Microsoft/hcsshim/internal/wclayer/importlayer.go')
-rw-r--r-- | vendor/github.com/Microsoft/hcsshim/internal/wclayer/importlayer.go | 127 |
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 +} |