Update vendor of containers/(storage,image)

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

vendor/github.com/containers/storage/pkg/lockfile/lastwrite.go

@@ -0,0 +1,82 @@
+package lockfile
+
+import (
+	"bytes"
+	cryptorand "crypto/rand"
+	"encoding/binary"
+	"os"
+	"sync/atomic"
+	"time"
+)
+
+// LastWrite is an opaque identifier of the last write to some *LockFile.
+// It can be used by users of a *LockFile to determine if the lock indicates changes
+// since the last check.
+//
+// Never construct a LastWrite manually; only accept it from *LockFile methods, and pass it back.
+type LastWrite struct {
+	// Never modify fields of a LastWrite object; it has value semantics.
+	state []byte // Contents of the lock file.
+}
+
+var lastWriterIDCounter uint64 // Private state for newLastWriterID
+
+const lastWriterIDSize = 64 // This must be the same as len(stringid.GenerateRandomID)
+// newLastWrite returns a new "last write" ID.
+// The value must be different on every call, and also differ from values
+// generated by other processes.
+func newLastWrite() LastWrite {
+	// The ID is (PID, time, per-process counter, random)
+	// PID + time represents both a unique process across reboots,
+	// and a specific time within the process; the per-process counter
+	// is an extra safeguard for in-process concurrency.
+	// The random part disambiguates across process namespaces
+	// (where PID values might collide), serves as a general-purpose
+	// extra safety, _and_ is used to pad the output to lastWriterIDSize,
+	// because other versions of this code exist and they don't work
+	// efficiently if the size of the value changes.
+	pid := os.Getpid()
+	tm := time.Now().UnixNano()
+	counter := atomic.AddUint64(&lastWriterIDCounter, 1)
+
+	res := make([]byte, lastWriterIDSize)
+	binary.LittleEndian.PutUint64(res[0:8], uint64(tm))
+	binary.LittleEndian.PutUint64(res[8:16], counter)
+	binary.LittleEndian.PutUint32(res[16:20], uint32(pid))
+	if n, err := cryptorand.Read(res[20:lastWriterIDSize]); err != nil || n != lastWriterIDSize-20 {
+		panic(err) // This shouldn't happen
+	}
+
+	return LastWrite{
+		state: res,
+	}
+}
+
+// serialize returns bytes to write to the lock file to represent the specified write.
+func (lw LastWrite) serialize() []byte {
+	if lw.state == nil {
+		panic("LastWrite.serialize on an uninitialized object")
+	}
+	return lw.state
+}
+
+// Equals returns true if lw matches other
+func (lw LastWrite) equals(other LastWrite) bool {
+	if lw.state == nil {
+		panic("LastWrite.equals on an uninitialized object")
+	}
+	if other.state == nil {
+		panic("LastWrite.equals with an uninitialized counterparty")
+	}
+	return bytes.Equal(lw.state, other.state)
+}
+
+// newLastWriteFromData returns a LastWrite corresponding to data that came from a previous LastWrite.serialize
+func newLastWriteFromData(serialized []byte) LastWrite {
+	if serialized == nil {
+		panic("newLastWriteFromData with nil data")
+	}
+	return LastWrite{
+		state: serialized,
+	}
+}