if !isValidRegion(sRegion, region) {
		return ch, ErrAuthorizationHeaderMalformed
	}
	if credElements[2] != string(stype) {
		if stype == serviceSTS {
			return ch, ErrInvalidServiceSTS
		}
		return ch, ErrInvalidServiceS3
	}
	cred.scope.service = credElements[2]
	if credElements[3] != "aws4_request" {
		return ch, ErrInvalidRequestVersion
	}
	cred.scope.request = credElements[3]

	enableSha256     bool
}

// Get the max throughput and iops numbers.
func objectSpeedTest(ctx context.Context, opts speedTestOpts) chan madmin.SpeedTestResult {
	ch := make(chan madmin.SpeedTestResult, 1)
	go func() {
		defer xioutil.SafeClose(ch)

		concurrency := opts.concurrencyStart

		if opts.autotune {
			// if we have less drives than concurrency then choose

		log.Fatalln(err)
	}

	maxObjectModTime := time.Now().Add(-ageDelta)

	// Next object is used to ignore new objects in the source & target
	nextObject := func(ch <-chan minio.ObjectInfo) (ctnt minio.ObjectInfo, ok bool) {
		for {
			ctnt, ok := <-ch
			if !ok {
				return minio.ObjectInfo{}, false
			}
			if ctnt.LastModified.Before(maxObjectModTime) {
				return ctnt, ok
			}
		}
	}

	// Close when we reach 0
	globalServiceFreezeCnt--
	if globalServiceFreezeCnt <= 0 {
		// Set to a nil channel.
		var _ch chan struct{}
		if val := globalServiceFreeze.Swap(_ch); val != nil {
			if ch, ok := val.(chan struct{}); ok && ch != nil {
				// Close previous non-nil channel.
				xioutil.SafeClose(ch)
			}
		}
		globalServiceFreezeCnt = 0 // Don't risk going negative.
	}
	globalServiceFreezeMu.Unlock()

// The context both allows returning errors on writes and to ensure that
// this isn't abandoned if the channel is no longer being read from.
func WriterToChannel(ctx context.Context, ch chan<- []byte) io.Writer {
	return &writerWrapper{ch: ch, ctx: ctx}
}

// bytesOrLength returns small (<=100b) byte slices as string, otherwise length.
func bytesOrLength(b []byte) string {
	if len(b) > 100 {

	"sync/atomic"
)

// GetByteBuffer returns a byte buffer from the pool.
var GetByteBuffer = func() []byte {
	return make([]byte, 0, 4096)
}

// Sub - subscriber entity.
type Sub[T Maskable] struct {
	ch     chan T
	types  Mask
	filter func(entry T) bool
}

// PubSub holds publishers and subscribers
type PubSub[T Maskable, M Maskable] struct {
	// atomics, keep at top:
	types          uint64

	r.readerWg.Add(1)
	go r.startReader()
	return &r
}

// NewElementReader - creates new JSON reader using readCloser.
func NewElementReader(ch chan simdjson.Object, err *error, args *json.ReaderArgs) *Reader {
	return &Reader{
		args:       args,
		decoded:    ch,
		err:        err,
		readCloser: nil,
	}
}

// safeCloser will wrap a Reader as a ReadCloser.