Migrate Sirupsen to sirupsen.

vendor/github.com/containerd/continuity/manifest.go

@@ -0,0 +1,144 @@
+package continuity
+
+import (
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"sort"
+
+	pb "github.com/containerd/continuity/proto"
+	"github.com/golang/protobuf/proto"
+)
+
+// Manifest provides the contents of a manifest. Users of this struct should
+// not typically modify any fields directly.
+type Manifest struct {
+	// Resources specifies all the resources for a manifest in order by path.
+	Resources []Resource
+}
+
+func Unmarshal(p []byte) (*Manifest, error) {
+	var bm pb.Manifest
+
+	if err := proto.Unmarshal(p, &bm); err != nil {
+		return nil, err
+	}
+
+	var m Manifest
+	for _, b := range bm.Resource {
+		r, err := fromProto(b)
+		if err != nil {
+			return nil, err
+		}
+
+		m.Resources = append(m.Resources, r)
+	}
+
+	return &m, nil
+}
+
+func Marshal(m *Manifest) ([]byte, error) {
+	var bm pb.Manifest
+	for _, resource := range m.Resources {
+		bm.Resource = append(bm.Resource, toProto(resource))
+	}
+
+	return proto.Marshal(&bm)
+}
+
+func MarshalText(w io.Writer, m *Manifest) error {
+	var bm pb.Manifest
+	for _, resource := range m.Resources {
+		bm.Resource = append(bm.Resource, toProto(resource))
+	}
+
+	return proto.MarshalText(w, &bm)
+}
+
+// BuildManifest creates the manifest for the given context
+func BuildManifest(ctx Context) (*Manifest, error) {
+	resourcesByPath := map[string]Resource{}
+	hardlinks := newHardlinkManager()
+
+	if err := ctx.Walk(func(p string, fi os.FileInfo, err error) error {
+		if err != nil {
+			return fmt.Errorf("error walking %s: %v", p, err)
+		}
+
+		if p == "/" {
+			// skip root
+			return nil
+		}
+
+		resource, err := ctx.Resource(p, fi)
+		if err != nil {
+			if err == ErrNotFound {
+				return nil
+			}
+			log.Printf("error getting resource %q: %v", p, err)
+			return err
+		}
+
+		// add to the hardlink manager
+		if err := hardlinks.Add(fi, resource); err == nil {
+			// Resource has been accepted by hardlink manager so we don't add
+			// it to the resourcesByPath until we merge at the end.
+			return nil
+		} else if err != errNotAHardLink {
+			// handle any other case where we have a proper error.
+			return fmt.Errorf("adding hardlink %s: %v", p, err)
+		}
+
+		resourcesByPath[p] = resource
+
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+
+	// merge and post-process the hardlinks.
+	hardlinked, err := hardlinks.Merge()
+	if err != nil {
+		return nil, err
+	}
+
+	for _, resource := range hardlinked {
+		resourcesByPath[resource.Path()] = resource
+	}
+
+	var resources []Resource
+	for _, resource := range resourcesByPath {
+		resources = append(resources, resource)
+	}
+
+	sort.Stable(ByPath(resources))
+
+	return &Manifest{
+		Resources: resources,
+	}, nil
+}
+
+// VerifyManifest verifies all the resources in a manifest
+// against files from the given context.
+func VerifyManifest(ctx Context, manifest *Manifest) error {
+	for _, resource := range manifest.Resources {
+		if err := ctx.Verify(resource); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// ApplyManifest applies on the resources in a manifest to
+// the given context.
+func ApplyManifest(ctx Context, manifest *Manifest) error {
+	for _, resource := range manifest.Resources {
+		if err := ctx.Apply(resource); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}