func NewDummyDataGen(totalLength, skipOffset int64) io.ReadSeeker {
	if totalLength < 0 {
		panic("Negative length passed to DummyDataGen!")
	}
	if skipOffset < 0 {
		panic("Negative rotations are not allowed")
	}

	skipOffset %= int64(len(alphabets))
	const multiply = 100
	as := bytes.Repeat(alphabets, multiply)
	b := as[skipOffset : skipOffset+int64(len(alphabets)*(multiply-1))]
	return &DummyDataGen{

	// Name of the object.
	Name string

	// Date and time when the object was last modified.
	ModTime time.Time

	// Total object size.
	Size int64

	// Actual size is the real size of the object uploaded by client.
	ActualSize *int64

	// IsDir indicates if the object is prefix.
	IsDir bool

	// Hex encoded unique entity tag of the object.
	ETag string

	// Version ID of this object.

func TestParseCopyPartRangeSpec(t *testing.T) {
	// Test success cases.
	successCases := []struct {
		rangeString string
		offsetBegin int64
		offsetEnd   int64
	}{
		{"bytes=2-5", 2, 5},
		{"bytes=2-9", 2, 9},
		{"bytes=2-2", 2, 2},
		{"bytes=0000-0006", 0, 6},
	}
	objectSize := int64(10)

	for _, successCase := range successCases {
		rs, err := parseCopyPartRangeSpec(successCase.rangeString)
		if err != nil {

		t.Fatalf("failed to create from map, got error %v", err)
	}

	var idVal int64
	_, ok := mapValue1["id"].(uint)
	if ok {
		t.Skipf("This test case skipped, because the db supports returning")
	}

	idVal, ok = mapValue1["id"].(int64)
	if !ok {
		t.Fatal("ret result missing id")
	}

	if int64(result1.ID) != idVal {
		t.Fatal("failed to create data from map with table, @id != id")
	}

	bts := make([]byte, 0, v.Msgsize())
	bts, _ = v.MarshalMsg(bts[0:0])
	b.SetBytes(int64(len(bts)))
	b.ReportAllocs()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		bts, _ = v.MarshalMsg(bts[0:0])
	}
}

func BenchmarkUnmarshalAccElem(b *testing.B) {
	v := AccElem{}
	bts, _ := v.MarshalMsg(nil)
	b.ReportAllocs()
	b.SetBytes(int64(len(bts)))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		_, err := v.UnmarshalMsg(bts)

	bts := make([]byte, 0, v.Msgsize())
	bts, _ = v.MarshalMsg(bts[0:0])
	b.SetBytes(int64(len(bts)))
	b.ReportAllocs()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		bts, _ = v.MarshalMsg(bts[0:0])
	}
}

func BenchmarkUnmarshalBatchJobExpire(b *testing.B) {
	v := BatchJobExpire{}
	bts, _ := v.MarshalMsg(nil)
	b.ReportAllocs()
	b.SetBytes(int64(len(bts)))
	b.ResetTimer()
	for i := 0; i < b.N; i++ {

}

// toInteger _ Safely convert interface to integer without causing panic.
func toInteger(val any) (int64, error) {
	switch v := val.(type) {
	case float64:
		return int64(v), nil
	case int64:
		return v, nil
	case int:
		return int64(v), nil
	case string:
		i, err := strconv.Atoi(v)
		return int64(i), err
	default:
		return 0, errors.New("Invalid number format")
	}
}

// object storage it will have the following parameters as constants.
//
//	maxPartsCount - 10000
//	maxMultipartPutObjectSize - 5TiB
func optimalPartSize(objectSize int64) (partSize int64, err error) {
	// object size is '-1' set it to 5TiB.
	if objectSize == -1 {
		objectSize = maxMultipartPutObjectSize
	}

	// object size is larger than supported maximum.

	r      *io.PipeReader
	wg     *sync.WaitGroup
	buffer map[int64][]byte
	err    error

	nextOffset int64
	m          sync.Mutex
}

func (w *writerAt) WriteAt(b []byte, offset int64) (n int, err error) {
	w.m.Lock()
	defer w.m.Unlock()

	if w.nextOffset == offset {
		n, err = w.w.Write(b)
		w.nextOffset += int64(n)
	} else {
		if offset > w.nextOffset+ftpMaxWriteOffset {

			return 0
		}
		if inv == 0xff {
			return ^int64(x)
		}
		return int64(x)
	}

	// Normal case is base-8 (octal) format.
	return p.parseOctal(b)
}

// formatNumeric encodes x into b using base-8 (octal) encoding if possible.
// Otherwise it will attempt to use base-256 (binary) encoding.
func (f *formatter) formatNumeric(b []byte, x int64) {
	if fitsInOctal(len(b), x) {
		f.formatOctal(b, x)