// which is the total amount of space, the total amount of free space, and the total
	// amount of free space available to the user that is associated with the calling thread.
	GetDiskFreeSpaceEx = kernel32.NewProc("GetDiskFreeSpaceExW")

	// GetDiskFreeSpace - https://msdn.microsoft.com/en-us/library/windows/desktop/aa364935(v=vs.85).aspx

// can be disabled via the corresponding `s3HFlag`.
//
// CAUTION: for requests involving large req/resp bodies ensure to pass the
// `traceHdrsS3HFlag`, otherwise both headers and body will be traced, causing
// high memory usage!
func s3APIMiddleware(f http.HandlerFunc, flags ...s3HFlag) http.HandlerFunc {
	// Collect all flags with bitwise-OR and assign operator
	var handlerFlags s3HFlag
	for _, flag := range flags {

	// by the Content-Type header field.
	ContentEncoding string

	// Date and time at which the object is no longer able to be cached
	Expires time.Time

	// Cache-Control - Specifies caching behavior along the request/reply chain
	CacheControl string

	// Specify object storage class
	StorageClass string

	ReplicationStatusInternal string
	ReplicationStatus         replication.StatusType

	globalObjectAPI = objLayer
	globalObjLayerMutex.Unlock()

	// When cache is enabled, Put and Get operations are passed
	// to underlying cache layer to manage object layer operation and disk caching
	// operation
	api := objectAPIHandlers{
		ObjectAPI: func() ObjectLayer {
			return globalObjectAPI
		},
	}

	// Register ListBuckets	handler.

		StartTime:      time.Now().UTC(),
	}
}

// ErrNotImplemented when a functionality is not implemented
var ErrNotImplemented = errors.New("not implemented")

// ReadFrom implements support for calling internal io.ReaderFrom implementations
// returns an error if the underlying ResponseWriter does not implement io.ReaderFrom
func (lrw *ResponseRecorder) ReadFrom(r io.Reader) (int64, error) {
	if lrw.ReaderFrom != nil {

	// Refer to https://cloud.google.com/storage/docs/transcoding#decompressive_transcoding
	// Need to set `Accept-Encoding` header to `gzip` when issuing a GetObject call, to be able
	// to download the object in compressed state.
	// Calling ReadCompressed with true accomplishes that.
	object := gcs.client.Bucket(gcs.Bucket).Object(gcs.getDest(key)).ReadCompressed(true)

	r, err = object.NewRangeReader(ctx, opts.startOffset, opts.length)
	if err != nil {

		// them if they could be an ancestor of an
		// aggregation.
	}
	return nil
}

// getAggregate() implementation for each AST node follows. This is
// called after calling aggregateRow() on each input row, to calculate
// the final aggregate result.

func (e *FuncExpr) getAggregate() (*Value, error) {
	switch e.getFunctionName() {
	case aggFnCount:

type Fault int

const (
	None Fault = iota
	MissingContentLength
	TooBigObject
	TooBigDecodedLength
	BadSignature
	BadMD5
	MissingUploadID
)

// Wrapper for calling HeadObject API handler tests for both Erasure multiple disks and FS single drive setup.
func TestAPIHeadObjectHandler(t *testing.T) {
	ExecObjectLayerAPITest(t, testAPIHeadObjectHandler, []string{"HeadObject"})
}

}

// Clone creates a new BucketReplicationStats copy
func (brs BucketReplicationStats) Clone() (c BucketReplicationStats) {
	// This is called only by replicationStats cache and already holds a
	// read lock before calling Clone()

	c = brs
	// We need to copy the map, so we do not reference the one in `brs`.
	c.Stats = make(map[string]*BucketReplicationStat, len(brs.Stats))
	for arn, st := range brs.Stats {
		// make a copy of `*st`

//     16 bytes of the encrypted ETag which will be a random
//     value.
//   - The object is a SSE-S3 encrypted single-part object.
//     In this case, the caller has to decrypt the ETag first
//     before calling Format.
//     S3 clients expect that the ETag of an SSE-S3 encrypted
//     single-part object is equal to the object's content MD5.
//     Formatting the SSE-S3 ETag before decryption will result