return tbsCertificate.extensions.firstOrNull {
        it.id == ObjectIdentifiers.SUBJECT_ALTERNATIVE_NAME
      }
    }

  val basicConstraints: Extension
    get() {
      return tbsCertificate.extensions.first {
        it.id == ObjectIdentifiers.BASIC_CONSTRAINTS
      }
    }

  /** Returns true if the certificate was signed by [issuer]. */
  @Throws(SignatureException::class)

  private final long k0;
  private final long k1;

  /**
   * @param c the number of compression rounds (must be positive)
   * @param d the number of finalization rounds (must be positive)
   * @param k0 the first half of the key
   * @param k1 the second half of the key
   */
  SipHashFunction(int c, int d, long k0, long k1) {
    checkArgument(

        // Write structure header
        SMBUtil.writeInt2(9, buffer, offset);
        SMBUtil.writeInt2(80 - 64, buffer, offset + 2);
        SMBUtil.writeInt4(200, buffer, offset + 4); // Total length

        // First notification at offset 80
        int notifyOffset = 80;
        SMBUtil.writeInt4(40, buffer, notifyOffset); // NextEntryOffset
        SMBUtil.writeInt4(1, buffer, notifyOffset + 4); // Action (ADDED)

    // We special-case for 0 or 1 elements, but going further is madness.
    if (!elements.hasNext()) {
      return of();
    }
    E first = elements.next();
    if (!elements.hasNext()) {
      return of(first);
    } else {
      return new ImmutableList.Builder<E>().add(first).addAll(elements).build();
    }
  }

  /**
   * Returns an immutable list containing the given elements, in order.
   *

 *       returned reader is closed.
 *   <li><b>Convenience methods:</b> These are implementations of common operations that are
 *       typically implemented by opening a reader using one of the methods in the first category,
 *       doing something and finally closing the reader that was opened.
 * </ul>
 *
 * <p>Several methods in this class, such as {@link #readLines()}, break the contents of the source

 *       returned reader is closed.
 *   <li><b>Convenience methods:</b> These are implementations of common operations that are
 *       typically implemented by opening a reader using one of the methods in the first category,
 *       doing something and finally closing the reader that was opened.
 * </ul>
 *
 * <p>Several methods in this class, such as {@link #readLines()}, break the contents of the source

</p>

<pre>
type Pair[A, B any] struct {
	a A
	b B
}

func (p Pair[A, B]) Swap() Pair[B, A]  { … }  // receiver declares A, B
func (p Pair[First, _]) First() First  { … }  // receiver declares First, corresponds to A in Pair
</pre>

<p>
If the receiver type is denoted by (a pointer to) an <a href="#Alias_declarations">alias</a>,

        assertNotNull("Encoded result should not be null", encoded);
        final byte[] decoded = Base64Util.decode(encoded);
        assertEquals("Decoded should have same length", 2, decoded.length);
        assertEquals("First byte should match", twoBytes[0], decoded[0]);
        assertEquals("Second byte should match", twoBytes[1], decoded[1]);
    }

    /**
     * Test backward compatibility with standard Base64
     *

        final int namesLength = numberOfNames * 18;
        final int statsLength = rDataLength - namesLength - 1;
        numberOfNames = src[srcIndex] & 0xFF;
        srcIndex++;
        // gotta read the mac first so we can populate addressArray with it
        System.arraycopy(src, srcIndex + namesLength, macAddress, 0, 6);
        srcIndex += readNodeNameArray(src, srcIndex);
        stats = new byte[statsLength];

  /** The [Buffer] of [sink]. Write to this and then flush/emit [sink]. */
  private val sinkBuffer: Buffer = sink.buffer
  private var writerClosed = false

  /** Lazily initialized on first use. */
  private var messageDeflater: MessageDeflater? = null

  // Masks are only a concern for client writers.
  private val maskKey: ByteArray? = if (isClient) ByteArray(4) else null