if len(p) == 0 {
		return 0, r.readErr(false)
	}

	r.mu.Lock()
	defer r.mu.Unlock()
	if err := r.readErr(true); err != nil {
		return 0, err
	}

	r.wg.Add(1)
	defer r.wg.Done()
	n, err = r.read(p)
	for err == ErrIsEmpty && r.block {
		r.writeCond.Wait()
		if err = r.readErr(true); err != nil {
			break
		}
		n, err = r.read(p)
	}

  } else {
    reader_.reset(new TensorSliceReader(filename));
    if (!reader_->status().ok()) {
      tsl::Set_TF_Status_from_Status(status, reader_->status());
      return;
    }
    var_to_shape_map_.reset(
        new TensorSliceReader::VarToShapeMap(reader_->GetVariableToShapeMap()));
    var_to_data_type_map_.reset(new TensorSliceReader::VarToDataTypeMap(
        reader_->GetVariableToDataTypeMap()));
  }
}

	if err != io.EOF {
		t.Fatal(err)
	}
}

func Test_metacacheReader_readAll(t *testing.T) {
	r := loadMetacacheSample(t)
	defer r.Close()
	var readErr error
	objs := make(chan metaCacheEntry, 1)
	var wg sync.WaitGroup
	wg.Add(1)
	go func() {
		readErr = r.readAll(t.Context(), objs)
		wg.Done()
	}()
	want := loadMetacacheSampleNames
	i := 0
	for entry := range objs {
		if entry.name != want[i] {

// NewMonitoredReader returns reference to a monitored reader that throttles reads to configured bandwidth for the
// bucket.
func NewMonitoredReader(ctx context.Context, m *Monitor, r io.Reader, opts *MonitorReaderOptions) *MonitoredReader {
	reader := MonitoredReader{
		r:        r,
		throttle: m.throttle(opts.BucketOptions),
		m:        m,
		opts:     opts,
		ctx:      ctx,
	}
	reader.m.init(opts.BucketOptions)
	return &reader

		closeBitrotWriters(writers)
		if err != nil {
			t.Fatalf("Test %d: failed to create random test data: %v", i, err)
		}

		readers := make([]io.ReaderAt, len(disks))
		for i, disk := range disks {
			shardFilesize := erasure.ShardFileSize(test.size)
			readers[i] = newBitrotReader(disk, nil, "testbucket", "testobject", shardFilesize, test.algorithm, bitrotWriterSum(writers[i]), erasure.ShardSize())
		}

	}
}

var UnreadRuneErrorTests = []struct {
	name string
	f    func(*Reader)
}{
	{"Read", func(r *Reader) { r.Read([]byte{0}) }},
	{"ReadByte", func(r *Reader) { r.ReadByte() }},
	{"UnreadRune", func(r *Reader) { r.UnreadRune() }},
	{"Seek", func(r *Reader) { r.Seek(0, io.SeekCurrent) }},
	{"WriteTo", func(r *Reader) { r.WriteTo(&Buffer{}) }},
}

func TestUnreadRuneError(t *testing.T) {

				case 2:
					httpStats.totalS3Errors.Inc("DeleteObject")
				case 3:
					httpStats.currentS3Requests.Inc("ListObjects")
				}
			}
		}(i)
	}

	for i := range numReaders {
		wg.Add(1)
		go func(readerID int) {
			defer wg.Done()
			for range opsPerGoroutine {
				_ = httpStats.toServerHTTPStats(false)
				_ = httpStats.totalS3Requests.Load(false)
				_ = httpStats.currentS3Requests.Load(false)

const maxDocumentSize = 10 << 20

// Reader - JSON record reader for S3Select.
type Reader struct {
	args       *ReaderArgs
	decoder    *jstream.Decoder
	valueCh    chan *jstream.MetaValue
	readCloser io.ReadCloser
}

// Read - reads single record.
func (r *Reader) Read(dst sql.Record) (sql.Record, error) {
	v, ok := <-r.valueCh
	if !ok {

import java.io.IOException;
import java.io.Reader;
import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * A {@link Reader} that concatenates multiple readers.
 *
 * @author Bin Zhu
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
final class MultiReader extends Reader {
  private final Iterator<? extends CharSource> it;
  private @Nullable Reader current;

  std::pair<std::unique_ptr<TensorSliceReader::VarToShapeMap>,
            std::unique_ptr<TensorSliceReader::VarToDataTypeMap> >
  BuildV2VarMaps();

  // Invariant: exactly one of "reader_" and "v2_reader_" is non-null.
  std::unique_ptr<TensorSliceReader> reader_;
  std::unique_ptr<BundleReader> v2_reader_;

  std::unique_ptr<TensorSliceReader::VarToShapeMap> var_to_shape_map_;