hdr := r.opts.HeaderSize // remaining header bytes
	var tokens int           // number of tokens to request

	if hdr > 0 { // available tokens go towards header first
		if hdr < b { // all of header can be accommodated
			r.opts.HeaderSize = 0
			need = int(math.Min(float64(b-hdr), float64(need))) // use remaining tokens towards payload
			tokens = need + hdr

	if totalSize == 0 {
		return 0, nil
	}

	var written int64
	for {
		buf := alignedBuf
		if totalSize > 0 {
			remaining := totalSize - written
			if remaining < int64(len(buf)) {
				buf = buf[:remaining]
			}
		}

		nr, err := io.ReadFull(r, buf)
		eof := errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF)
		if err != nil && !eof {

			sr.fillReady <- int64(n)
		}
	}()

	sr.fillReq <- struct{}{} // initial fill

	return sr
}

// remaining returns the number of unread bytes
// if EOF for the underlying reader has not yet been found,
// maximum possible integer value will be returned
func (s *scanner) remaining() int64 {
	if atomic.LoadInt64(&s.end) == maxInt {
		return maxInt
	}
	return atomic.LoadInt64(&s.end) - s.pos
}

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

### Apache License ###

All the remaining project files are covered by the Apache license:

Copyright (c) 2011-2019 Canonical Ltd

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.

   *     {@link ByteOrder#LITTLE_ENDIAN}, to which a BYTES-long byte representation of this instance
   *     is written. In the process increases the position of {@link ByteBuffer} by BYTES.
   */
  void writeTo(ByteBuffer buffer) {
    checkNotNull(buffer);
    checkArgument(
        buffer.remaining() >= BYTES,

		}
		return -n, Number, nil
	case 'f':
		if d.remaining() < 4 {
			return nil, Unknown, d.mkError(ErrUnexpectedEOF)
		}
		//nolint:gocritic
		if d.next() == 'a' && d.next() == 'l' && d.next() == 's' && d.next() == 'e' {
			return false, Boolean, nil
		}
		return nil, Unknown, d.mkError(ErrSyntax, "in literal false")
	case 't':
		if d.remaining() < 3 {
			return nil, Unknown, d.mkError(ErrUnexpectedEOF)
		}

		c := scanner.next()
		if scanner.readerErr != nil {
			t.Fatal(scanner.readerErr)
		}
		if c != data[i] {
			t.Fatalf("expected %s, got %s", string(data[i]), string(c))
		}
		t.Logf("pos=%d remaining=%d (%s)", i, r.Len(), string(c))
		i++
	}
}

type mockReader struct {
	pos       int
	mockData  byte
	failAfter int
}

func newMockReader(failAfter int, data byte) *mockReader {

      assertTrue(bb.remaining() >= chunkSize);
      for (int i = 0; i < chunkSize; i++) {
        out.write(bb.get());
      }
    }

    @Override
    protected void processRemaining(ByteBuffer bb) {
      assertFalse(remainingCalled);
      remainingCalled = true;
      assertEquals(ByteOrder.LITTLE_ENDIAN, bb.order());
      assertTrue(bb.remaining() > 0);

      int remaining = queue.size();
      while (queueIterator.hasNext()) {
        Integer element = queueIterator.next();
        remaining--;
        assertThat(elements).contains(element);
        if (random.nextBoolean()) {
          elements.remove(element);
          queueIterator.remove();
        }
      }
      assertThat(remaining).isEqualTo(0);
      assertIntact(queue);

     * <p>
     * Continues an MD4 message digest operation, by filling the buffer,
     * transform(ing) data in 512-bit message block(s), updating the variables
     * context and count, and leaving (buffering) the remaining bytes in buffer
     * for the next update or finish.
     *
     * @param    input    input block
     * @param    offset    start of meaningful bytes in input