// 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.

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

type LimitWriter struct {
	io.Writer
	skipBytes int64
	wLimit    int64
}

// Write implements the io.Writer interface limiting upto
// configured length, also skips the first N bytes.
func (w *LimitWriter) Write(p []byte) (n int, err error) {
	n = len(p)
	var n1 int
	if w.skipBytes > 0 {
		if w.skipBytes >= int64(len(p)) {
			w.skipBytes -= int64(len(p))
			return n, nil
		}
		p = p[w.skipBytes:]

	readers       []io.ReaderAt
	orgReaders    []io.ReaderAt
	dataBlocks    int
	offset        int64
	shardSize     int64
	shardFileSize int64
	buf           [][]byte
	readerToBuf   []int
	stashBuffer   []byte
}

// newParallelReader returns parallelReader.
func newParallelReader(readers []io.ReaderAt, e Erasure, offset, totalLength int64) *parallelReader {
	r2b := make([]int, len(readers))
	for i := range r2b {
		r2b[i] = i
	}

		{bucketNames[0], objectNames[0], uploadIDs[0], 4, "mnop", "e132e96a5ddad6da8b07bba6f6131fef", int64(len("abcd"))},
		// Part with size larger than 5Mb.
		{bucketNames[0], objectNames[0], uploadIDs[0], 5, string(validPart), validPartMD5, int64(len(validPart))},
		{bucketNames[0], objectNames[0], uploadIDs[0], 6, string(validPart), validPartMD5, int64(len(validPart))},

type Stats struct {
	TotalEvents        int64 // Deprecated
	EventsSkipped      int64
	CurrentQueuedCalls int64 // Deprecated
	EventsErrorsTotal  int64 // Deprecated
	CurrentSendCalls   int64 // Deprecated

	TargetStats map[TargetID]TargetStat
}

// TargetStat is the stats of a single target.
type TargetStat struct {

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{

type WarmBackendGetOpts struct {
	startOffset int64
	length      int64
}

// WarmBackend provides interface to be implemented by remote tier backends
type WarmBackend interface {
	Put(ctx context.Context, object string, r io.Reader, length int64) (remoteVersionID, error)
	PutWithMeta(ctx context.Context, object string, r io.Reader, length int64, meta map[string]string) (remoteVersionID, error)

			timeToResponse  time.Duration
			timeToFirstByte time.Duration
			outputBytes     int64 = -1 // -1: unknown output bytes
			headerBytes     int64
		)

		tc, ok := r.Context().Value(mcontext.ContextTraceKey).(*mcontext.TraceCtxt)
		if ok {
			statusCode = tc.ResponseRecorder.StatusCode
			outputBytes = int64(tc.ResponseRecorder.Size())
			headerBytes = int64(tc.ResponseRecorder.HeaderSize())

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 {