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-rw-r--r--libpod/diff.go56
1 files changed, 56 insertions, 0 deletions
diff --git a/libpod/diff.go b/libpod/diff.go
index f348e6b81..925bda927 100644
--- a/libpod/diff.go
+++ b/libpod/diff.go
@@ -1,6 +1,9 @@
package libpod
import (
+ "archive/tar"
+ "io"
+
"github.com/containers/libpod/libpod/layers"
"github.com/containers/storage/pkg/archive"
"github.com/pkg/errors"
@@ -44,6 +47,59 @@ func (r *Runtime) GetDiff(from, to string) ([]archive.Change, error) {
return rchanges, err
}
+// skipFileInTarAchive is an archive.TarModifierFunc function
+// which tells archive.ReplaceFileTarWrapper to skip files
+// from the tarstream
+func skipFileInTarAchive(path string, header *tar.Header, content io.Reader) (*tar.Header, []byte, error) {
+ return nil, nil, nil
+}
+
+// GetDiffTarStream returns the differences between the two images, layers, or containers.
+// It is the same functionality as GetDiff() except that it returns a tarstream
+func (r *Runtime) GetDiffTarStream(from, to string) (io.ReadCloser, error) {
+ toLayer, err := r.getLayerID(to)
+ if err != nil {
+ return nil, err
+ }
+ fromLayer := ""
+ if from != "" {
+ fromLayer, err = r.getLayerID(from)
+ if err != nil {
+ return nil, err
+ }
+ }
+ rc, err := r.store.Diff(fromLayer, toLayer, nil)
+ if err != nil {
+ return nil, err
+ }
+
+ // Skip files in the tar archive which are listed
+ // in containerMounts map. Just as in the GetDiff()
+ // function from above
+ filterMap := make(map[string]archive.TarModifierFunc)
+ for key := range containerMounts {
+ filterMap[key[1:]] = skipFileInTarAchive
+ // In the tarstream directories always include a trailing '/'.
+ // For simplicity this duplicates every entry from
+ // containerMounts with a trailing '/', as containerMounts
+ // does not use trailing '/' for directories.
+ filterMap[key[1:]+"/"] = skipFileInTarAchive
+ }
+
+ filteredTarStream := archive.ReplaceFileTarWrapper(rc, filterMap)
+ return filteredTarStream, nil
+}
+
+// ApplyDiffTarStream applies the changes stored in 'diff' to the layer 'to'
+func (r *Runtime) ApplyDiffTarStream(to string, diff io.Reader) error {
+ toLayer, err := r.getLayerID(to)
+ if err != nil {
+ return err
+ }
+ _, err = r.store.ApplyDiff(toLayer, diff)
+ return err
+}
+
// GetLayerID gets a full layer id given a full or partial id
// If the id matches a container or image, the id of the top layer is returned
// If the id matches a layer, the top layer id is returned