partNumber := partI.Number
		if partID != partNumber {
			internalLogIf(ctx, fmt.Errorf("part.%d.meta has incorrect corresponding part number: expected %d, got %d", partID, partID, partI.Number))
			return oi, InvalidPart{
				PartNumber: partID,
			}
		}

		// Add the current part.
		fi.AddObjectPart(partI.Number, partI.ETag, partI.Size, partI.ActualSize, partI.ModTime, partI.Index, partI.Checksums)
	}

	m.Set(driveWaitingIO, float64(disk.Metrics.TotalWaiting), labels...)

	// Append the api label for the drive API latencies.
	labels = append(labels, "api", "")
	lastIdx := len(labels) - 1
	for apiName, latency := range disk.Metrics.LastMinute {
		labels[lastIdx] = "storage." + apiName
		m.Set(driveAPILatencyMicros, float64(latency.Avg().Microseconds()),
			labels...)
	}
}

	CopyObjectPart(ctx context.Context, srcBucket, srcObject, destBucket, destObject string, uploadID string, partID int,
		startOffset int64, length int64, srcInfo ObjectInfo, srcOpts, dstOpts ObjectOptions) (info PartInfo, err error)
	PutObjectPart(ctx context.Context, bucket, object, uploadID string, partID int, data *PutObjReader, opts ObjectOptions) (info PartInfo, err error)

		// Test case  1-4.
		// Cases with invalid bucket name.
		{bucketName: ".test", objName: "obj", PartID: 1, expectedError: fmt.Errorf("%s", "Bucket name invalid: .test")},
		{bucketName: "------", objName: "obj", PartID: 1, expectedError: fmt.Errorf("%s", "Bucket name invalid: ------")},
		{
			bucketName: "$this-is-not-valid-too", objName: "obj", PartID: 1,
			expectedError: fmt.Errorf("%s", "Bucket name invalid: $this-is-not-valid-too"),
		},

}

// EncryptMultiPart encrypts an io.Reader which must be the body of
// multi-part PUT request. It derives an unique encryption key from
// the partID and the object key.
func EncryptMultiPart(r io.Reader, partID int, key ObjectKey) io.Reader {
	partKey := key.DerivePartKey(uint32(partID))
	return EncryptSinglePart(r, ObjectKey(partKey))
}

// DecryptSinglePart decrypts an io.Writer which must an object

	}
}

var derivePartKeyTest = []struct {
	PartID  uint32
	PartKey string
}{
	{PartID: 0, PartKey: "aa7855e13839dd767cd5da7c1ff5036540c9264b7a803029315e55375287b4af"},
	{PartID: 1, PartKey: "a3e7181c6eed030fd52f79537c56c4d07da92e56d374ff1dd2043350785b37d8"},
	{PartID: 10000, PartKey: "f86e65c396ed52d204ee44bd1a0bbd86eb8b01b7354e67a3b3ae0e34dd5bd115"},
}

	}
	entries.reuse = true
	truncated := entries.len() > o.Limit || err == nil
	entries.truncate(o.Limit)
	if !o.Transient && truncated {
		if o.ID == "" {
			entries.listID = mustGetUUID()
		} else {
			entries.listID = o.ID
		}
	}
	if !truncated {
		return entries, io.EOF
	}
	return entries, nil
}

// listMerged will list across all sets and return a merged results stream.

	if err != nil {
		t.Fatalf("Failed to create a multipart upload - %v", err)
	}

	var uploadedParts []CompletePart
	for _, partID := range []int{2, 1} {
		pInfo, err1 := objLayer.PutObjectPart(ctx, bucket, object, res.UploadID, partID, mustGetPutObjReader(t, bytes.NewReader(data), int64(len(data)), "", ""), opts)
		if err1 != nil {
			t.Fatalf("Failed to upload a part - %v", err1)
		}

func (s *erasureSets) PutObjectPart(ctx context.Context, bucket, object, uploadID string, partID int, data *PutObjReader, opts ObjectOptions) (info PartInfo, err error) {
	set := s.getHashedSet(object)
	return set.PutObjectPart(ctx, bucket, object, uploadID, partID, data, opts)
}

// GetMultipartInfo - return multipart metadata info uploaded at hashedSet.

	metadata       map[string]string

	partDecRelOffset, partEncRelOffset int64

	copySource bool
	// Customer Key
	customerKeyHeader string
}

func (d *DecryptBlocksReader) buildDecrypter(partID int) error {
	m := cloneMSS(d.metadata)
	// Initialize the first decrypter; new decrypters will be
	// initialized in Read() operation as needed.
	var key []byte
	var err error
	if d.copySource {