if startOffset > fi.Size || startOffset+length > fi.Size {
		return InvalidRange{startOffset, length, fi.Size}
	}

	// Get start part index and offset.
	partIndex, partOffset, err := fi.ObjectToPartOffset(ctx, startOffset)
	if err != nil {
		return InvalidRange{startOffset, length, fi.Size}
	}

	// Calculate endOffset according to length
	endOffset := startOffset

		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrExcessData: {
		Code:           "ExcessData",
		Description:    "More data provided than indicated content length",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrPolicyTooLarge: {
		Code:           "PolicyTooLarge",
		Description:    "Policy exceeds the maximum allowed document size.",

func (z *erasureServerPools) CopyObjectPart(ctx context.Context, srcBucket, srcObject, destBucket, destObject string, uploadID string, partID int, startOffset int64, length int64, srcInfo ObjectInfo, srcOpts, dstOpts ObjectOptions) (PartInfo, error) {
	if err := checkNewMultipartArgs(ctx, srcBucket, srcObject); err != nil {
		return PartInfo{}, err
	}

	rotational bool
	walkMu     *sync.Mutex
	walkReadMu *sync.Mutex
}

// checkPathLength - returns error if given path name length more than 255
func checkPathLength(pathName string) error {
	// Apple OS X path length is limited to 1016
	if runtime.GOOS == "darwin" && len(pathName) > 1016 {
		return errFileNameTooLong
	}

	// Disallow more than 1024 characters on windows, there

			// Since there are cases for which ListObjects fails, this is
			// necessary. Test passes as expected, but the output values
			// are verified for correctness here.
			if err == nil && testCase.shouldPass {
				// The length of the expected ListObjectsResult.Objects
				// should match in both expected result from test cases
				// and in the output. On failure calling t.Fatalf,
				// otherwise it may lead to index out of range error in

	req.Header.Set("x-amz-content-sha256", "STREAMING-AWS4-HMAC-SHA256-PAYLOAD")
	req.Header.Set("content-encoding", "aws-chunked")
	req.Header.Set("x-amz-decoded-content-length", strconv.FormatInt(dataLength, 10))
	req.Header.Set("content-length", strconv.FormatInt(contentLength, 10))

	// Seek back to beginning.
	body.Seek(0, 0)

	// Add body
	req.Body = io.NopCloser(body)
	req.ContentLength = contentLength

	{file: "myobject", offset: 1, length: 120, algorithm: SHA256, expError: errFileCorrupt},     // 4
	{file: "myobject", offset: 3, length: 1100, algorithm: SHA256, expError: nil},               // 5
	{file: "myobject", offset: 2, length: 100, algorithm: SHA256, expError: errFileCorrupt},     // 6

var metaDataPool = sync.Pool{New: func() interface{} { return make([]byte, 0, metaDataReadDefault) }}

// metaDataPoolGet will return a byte slice with capacity at least metaDataReadDefault.
// It will be length 0.
func metaDataPoolGet() []byte {
	return metaDataPool.Get().([]byte)[:0]
}

// metaDataPoolPut will put an unused small buffer back into the pool.
func metaDataPoolPut(buf []byte) {

	if _, ok := r.Header[xhttp.ContentMD5]; !ok {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrMissingContentMD5), r.URL)
		return
	}

	// Content-Length is required and should be non-zero
	// http://docs.aws.amazon.com/AmazonS3/latest/API/multiobjectdeleteapi.html
	if r.ContentLength <= 0 {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrMissingContentLength), r.URL)

		return
	}

	// Error out if Content-Length is missing.
	if r.ContentLength <= 0 {
		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrMissingContentLength), r.URL)
		return
	}

	// Error out if Content-Length is beyond allowed size.
	if r.ContentLength > maxBucketPolicySize {