Switch to golang/dep.

vendor/github.com/docker/distribution/registry/storage/walk.go

@@ -0,0 +1,59 @@
+package storage
+
+import (
+	"errors"
+	"fmt"
+	"sort"
+
+	"github.com/docker/distribution/context"
+	storageDriver "github.com/docker/distribution/registry/storage/driver"
+)
+
+// ErrSkipDir is used as a return value from onFileFunc to indicate that
+// the directory named in the call is to be skipped. It is not returned
+// as an error by any function.
+var ErrSkipDir = errors.New("skip this directory")
+
+// WalkFn is called once per file by Walk
+// If the returned error is ErrSkipDir and fileInfo refers
+// to a directory, the directory will not be entered and Walk
+// will continue the traversal.  Otherwise Walk will return
+type WalkFn func(fileInfo storageDriver.FileInfo) error
+
+// Walk traverses a filesystem defined within driver, starting
+// from the given path, calling f on each file
+func Walk(ctx context.Context, driver storageDriver.StorageDriver, from string, f WalkFn) error {
+	children, err := driver.List(ctx, from)
+	if err != nil {
+		return err
+	}
+	sort.Stable(sort.StringSlice(children))
+	for _, child := range children {
+		// TODO(stevvooe): Calling driver.Stat for every entry is quite
+		// expensive when running against backends with a slow Stat
+		// implementation, such as s3. This is very likely a serious
+		// performance bottleneck.
+		fileInfo, err := driver.Stat(ctx, child)
+		if err != nil {
+			return err
+		}
+		err = f(fileInfo)
+		skipDir := (err == ErrSkipDir)
+		if err != nil && !skipDir {
+			return err
+		}
+
+		if fileInfo.IsDir() && !skipDir {
+			if err := Walk(ctx, driver, child, f); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// pushError formats an error type given a path and an error
+// and pushes it to a slice of errors
+func pushError(errors []error, path string, err error) []error {
+	return append(errors, fmt.Errorf("%s: %s", path, err))
+}