if length < 0 {
		length = fi.Size - startOffset
	}

	// Reply back invalid range if the input offset and length fall out of range.
	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 {

func GetObject(ctx context.Context, api ObjectLayer, bucket, object string, startOffset int64, length int64, writer io.Writer, etag string, opts ObjectOptions) (err error) {
	var header http.Header
	if etag != "" {
		header.Set("ETag", etag)
	}
	Range := &HTTPRangeSpec{Start: startOffset, End: startOffset + length}

	reader, err := api.GetObjectNInfo(ctx, bucket, object, Range, header, opts)
	if err != nil {

	if partRangeErr := checkCopyPartRangeWithSize(rs, actualPartSize); partRangeErr != nil {
		writeCopyPartErr(ctx, w, partRangeErr, r.URL)
		return
	}

	// Get the object offset & length
	startOffset, length, err := rs.GetOffsetLength(actualPartSize)
	if err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}

	// maximum copy size for multipart objects in a single operation