// 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

			current.Last = o.name
		}
		if n > 0 || current.n == 0 {
			current.EOS = true
			finishBlock()
		}
	}()
	return &w
}

// Close the stream.
// The incoming channel must be closed before calling this.
// Returns the first error the occurred during the writing if any.
func (w *metacacheBlockWriter) Close() error {
	w.wg.Wait()
	return w.streamErr
}

type metacacheBlock struct {
	data  []byte

// values such as ErasureInfo, ChecksumInfo.
//
// Metadata is only updated to new values, existing values
// stay as is, if you wish to update all values you should
// update all metadata freshly before calling this function
// in-case you wish to clear existing metadata.
func (x *xlMetaV2) UpdateObjectVersion(fi FileInfo) error {
	if fi.VersionID == "" {
		// this means versioning is not yet

	cases := []struct {
		numerator, denominator, ceiling int64
	}{
		{0, 1, 0},
		{-1, 2, 0},
		{1, 2, 1},
		{1, 1, 1},
		{3, 2, 2},
		{54, 11, 5},
		{45, 11, 5},
		{-4, 3, -1},
		{4, -3, -1},
		{-4, -3, 2},
		{3, 0, 0},
	}
	for i, testCase := range cases {
		ceiling := ceilFrac(testCase.numerator, testCase.denominator)
		if ceiling != testCase.ceiling {

		delete(sys.metadataMap, bucket)
		globalBucketMonitor.DeleteBucket(bucket)
	}
}

// Set - sets a new metadata in-memory.
// Only a shallow copy is saved and fields with references
// cannot be modified without causing a race condition,
// so they should be replaced atomically and not appended to, etc.
// Data is not persisted to disk.
func (sys *BucketMetadataSys) Set(bucket string, meta BucketMetadata) {
	if !isMinioMetaBucketName(bucket) {

// Add policy conditionals.
const (
	policyCondEqual         = "eq"
	policyCondStartsWith    = "starts-with"
	policyCondContentLength = "content-length-range"
)

// toString - Safely convert interface to string without causing panic.
func toString(val interface{}) string {
	switch v := val.(type) {
	case string:
		return v
	default:
		return ""
	}
}

// toLowerString - safely convert interface to lower string

	if fi1.Mode() != fi2.Mode() {
		return false
	}
	return fi1.Size() == fi2.Size()
}

// DirectioAlignSize - DirectIO alignment needs to be 4K. Defined here as
// directio.AlignSize is defined as 0 in MacOS causing divide by 0 error.
const DirectioAlignSize = 4096

// CopyAligned - copies from reader to writer using the aligned input
// buffer, it is expected that input buffer is page aligned to