return new ForwardingSource(source) {
        long totalBytesRead = 0L;

        @Override public long read(Buffer sink, long byteCount) throws IOException {
          long bytesRead = super.read(sink, byteCount);
          // read() returns the number of bytes read, or -1 if this source is exhausted.
          totalBytesRead += bytesRead != -1 ? bytesRead : 0;

    <magic priority="50">
       <match value="Windows Media Audio" type="unicodeLE" offset="0:8192" />
    </magic>
  </mime-type>

  <mime-type type="audio/x-pn-realaudio">
    <_comment>Real Audio</_comment>
    <alias type="audio/x-realaudio" />
    <magic priority="50">
      <match value="0x2e7261fd" type="big32" offset="0"/>
    </magic>
    <glob pattern="*.ram"/>
    <glob pattern="*.ra"/>

            int rs = Math.min(bufSize, (int) ( length - p ));
            int read = is.read(buffer, 0, rs);
            if ( read < 0 ) {
                fail("Unexpected EOF at " + p);
            }

            byte verify[] = new byte[read];
            randBytes(r, verify);
            byte actual[] = Arrays.copyOfRange(buffer, 0, read);

            assertArrayEquals("Data matches at offset " + p, actual, verify);

                + extension.getVersion();
        final ClassRealm realm = classWorld.newRealm(realmId, null);
        Set<String> providedArtifacts = Collections.emptySet();
        String classLoadingStrategy = extension.getClassLoadingStrategy();
        if (STRATEGY_PARENT_FIRST.equals(classLoadingStrategy)) {
            realm.importFrom(parentRealm, "");
        } else if (STRATEGY_PLUGIN.equals(classLoadingStrategy)) {

		},
		config.HelpKV{
			Key:         Sleep,
			Description: `maximum sleep duration between objects to slow down heal operation` + defaultHelpPostfix(Sleep),
			Optional:    true,
			Type:        "duration",
		},
		config.HelpKV{
			Key:         IOCount,
			Description: `maximum IO requests allowed between objects to slow down heal operation` + defaultHelpPostfix(IOCount),
			Optional:    true,
			Type:        "int",
		},
		config.HelpKV{

    @Throws(IOException::class)
    override fun read(
      sink: Buffer,
      byteCount: Long,
    ): Long {
      while (left == 0) {
        source.skip(padding.toLong())
        padding = 0
        if (flags and FLAG_END_HEADERS != 0) return -1L
        readContinuationHeader()
        // TODO: test case for empty continuation header?
      }

      val read = source.read(sink, minOf(byteCount, left.toLong()))

			t.Fatalf("Impossible read specified: %d %d %d", skipLen, readLen, oSize)
		}

		var cumulativeSum, cumulativeEncSum int64
		toRead := readLen
		readStart := false
		for i, v := range s {
			partOffset := int64(0)
			partDarePkgOffset := int64(0)
			if !readStart && cumulativeSum+v > skipLen {
				// Read starts at the current part
				readStart = true

		return false, fmt.Errorf("RUnlock attempted on a write locked entity: %s", args.Resources[0])
	}
	if locksHeld > ReadLock {
		l.lockMap[args.Resources[0]] = locksHeld - ReadLock // Remove one of the read locks held
	} else {
		delete(l.lockMap, args.Resources[0]) // Remove the (last) read lock
	}
	return reply, nil
}

    val derReader = DerReader(buffer)

    derReader.read("test") { header ->
      assertThat(header.tag).isEqualTo(16L)

      derReader.read("test") { header2 ->
        assertThat(header2.tag).isEqualTo(21L)
        assertThat(derReader.readOctetString()).isEqualTo("Smith".encodeUtf8())
      }

      derReader.read("test") { header3 ->
        assertThat(header3.tag).isEqualTo(1L)

    stream = io.BytesIO(b"data")
    file = UploadFile(filename="file", file=stream, size=4)
    assert await file.read() == b"data"
    assert file.size == 4
    await file.write(b" and more data!")
    assert await file.read() == b""
    assert file.size == 19
    await file.seek(0)
    assert await file.read() == b"data and more data!"