VOL-381 add unum container to support ONOS cluster formation under swarm
Change-Id: Ic260edda19bb199ed040f05164ab605f28c919d0
diff --git a/unum/vendor/github.com/opencontainers/go-digest/algorithm.go b/unum/vendor/github.com/opencontainers/go-digest/algorithm.go
new file mode 100644
index 0000000..a3c4480
--- /dev/null
+++ b/unum/vendor/github.com/opencontainers/go-digest/algorithm.go
@@ -0,0 +1,144 @@
+package digest
+
+import (
+ "crypto"
+ "fmt"
+ "hash"
+ "io"
+)
+
+// Algorithm identifies and implementation of a digester by an identifier.
+// Note the that this defines both the hash algorithm used and the string
+// encoding.
+type Algorithm string
+
+// supported digest types
+const (
+ SHA256 Algorithm = "sha256" // sha256 with hex encoding
+ SHA384 Algorithm = "sha384" // sha384 with hex encoding
+ SHA512 Algorithm = "sha512" // sha512 with hex encoding
+
+ // Canonical is the primary digest algorithm used with the distribution
+ // project. Other digests may be used but this one is the primary storage
+ // digest.
+ Canonical = SHA256
+)
+
+var (
+ // TODO(stevvooe): Follow the pattern of the standard crypto package for
+ // registration of digests. Effectively, we are a registerable set and
+ // common symbol access.
+
+ // algorithms maps values to hash.Hash implementations. Other algorithms
+ // may be available but they cannot be calculated by the digest package.
+ algorithms = map[Algorithm]crypto.Hash{
+ SHA256: crypto.SHA256,
+ SHA384: crypto.SHA384,
+ SHA512: crypto.SHA512,
+ }
+)
+
+// Available returns true if the digest type is available for use. If this
+// returns false, Digester and Hash will return nil.
+func (a Algorithm) Available() bool {
+ h, ok := algorithms[a]
+ if !ok {
+ return false
+ }
+
+ // check availability of the hash, as well
+ return h.Available()
+}
+
+func (a Algorithm) String() string {
+ return string(a)
+}
+
+// Size returns number of bytes returned by the hash.
+func (a Algorithm) Size() int {
+ h, ok := algorithms[a]
+ if !ok {
+ return 0
+ }
+ return h.Size()
+}
+
+// Set implemented to allow use of Algorithm as a command line flag.
+func (a *Algorithm) Set(value string) error {
+ if value == "" {
+ *a = Canonical
+ } else {
+ // just do a type conversion, support is queried with Available.
+ *a = Algorithm(value)
+ }
+
+ if !a.Available() {
+ return ErrDigestUnsupported
+ }
+
+ return nil
+}
+
+// Digester returns a new digester for the specified algorithm. If the algorithm
+// does not have a digester implementation, nil will be returned. This can be
+// checked by calling Available before calling Digester.
+func (a Algorithm) Digester() Digester {
+ return &digester{
+ alg: a,
+ hash: a.Hash(),
+ }
+}
+
+// Hash returns a new hash as used by the algorithm. If not available, the
+// method will panic. Check Algorithm.Available() before calling.
+func (a Algorithm) Hash() hash.Hash {
+ if !a.Available() {
+ // Empty algorithm string is invalid
+ if a == "" {
+ panic(fmt.Sprintf("empty digest algorithm, validate before calling Algorithm.Hash()"))
+ }
+
+ // NOTE(stevvooe): A missing hash is usually a programming error that
+ // must be resolved at compile time. We don't import in the digest
+ // package to allow users to choose their hash implementation (such as
+ // when using stevvooe/resumable or a hardware accelerated package).
+ //
+ // Applications that may want to resolve the hash at runtime should
+ // call Algorithm.Available before call Algorithm.Hash().
+ panic(fmt.Sprintf("%v not available (make sure it is imported)", a))
+ }
+
+ return algorithms[a].New()
+}
+
+// FromReader returns the digest of the reader using the algorithm.
+func (a Algorithm) FromReader(rd io.Reader) (Digest, error) {
+ digester := a.Digester()
+
+ if _, err := io.Copy(digester.Hash(), rd); err != nil {
+ return "", err
+ }
+
+ return digester.Digest(), nil
+}
+
+// FromBytes digests the input and returns a Digest.
+func (a Algorithm) FromBytes(p []byte) Digest {
+ digester := a.Digester()
+
+ if _, err := digester.Hash().Write(p); err != nil {
+ // Writes to a Hash should never fail. None of the existing
+ // hash implementations in the stdlib or hashes vendored
+ // here can return errors from Write. Having a panic in this
+ // condition instead of having FromBytes return an error value
+ // avoids unnecessary error handling paths in all callers.
+ panic("write to hash function returned error: " + err.Error())
+ }
+
+ return digester.Digest()
+}
+
+// FromString digests the string input and returns a Digest.
+func (a Algorithm) FromString(s string) Digest {
+ return a.FromBytes([]byte(s))
+}