Method readHeaderPayload

java/org/apache/coyote/http2/Http2Parser.java:515–585

(int streamId, int payloadSize, ByteBuffer buffer)

    protected void readHeaderPayload(int streamId, int payloadSize, ByteBuffer buffer)
            throws Http2Exception, IOException {

        if (log.isTraceEnabled()) {
            log.trace(sm.getString("http2Parser.processFrameHeaders.payload", connectionId, Integer.valueOf(streamId),
                    Integer.valueOf(payloadSize)));
        }

        int remaining = payloadSize;

        while (remaining > 0) {
            if (headerReadBuffer.remaining() == 0) {
                // Buffer needs expansion
                int newSize;
                if (headerReadBuffer.capacity() < payloadSize) {
                    // First step, expand to the current payload. That should
                    // cover most cases.
                    newSize = payloadSize;
                } else {
                    // Header must be spread over multiple frames. Keep doubling
                    // buffer size until the header can be read.
                    newSize = headerReadBuffer.capacity() * 2;
                }
                headerReadBuffer = ByteBufferUtils.expand(headerReadBuffer, newSize);
            }
            int toRead = Math.min(headerReadBuffer.remaining(), remaining);
            // headerReadBuffer in write mode
            if (buffer == null) {
                input.fill(true, headerReadBuffer, toRead);
            } else {
                int oldLimit = buffer.limit();
                buffer.limit(buffer.position() + toRead);
                headerReadBuffer.put(buffer);
                buffer.limit(oldLimit);
            }
            // switch to read mode
            headerReadBuffer.flip();
            try {
                hpackDecoder.decode(headerReadBuffer);
            } catch (HpackException hpe) {
                throw new ConnectionException(sm.getString("http2Parser.processFrameHeaders.decodingFailed"),
                        Http2Error.COMPRESSION_ERROR, hpe);
            } catch (IllegalArgumentException iae) {
                throw new StreamException("Invalid headers", Http2Error.PROTOCOL_ERROR, streamId, iae);
            }

            // switches to write mode
            headerReadBuffer.compact();
            remaining -= toRead;

            if (hpackDecoder.isHeaderCountExceeded()) {
                StreamException headerException = new StreamException(
                        sm.getString("http2Parser.headerLimitCount", connectionId, Integer.valueOf(streamId)),
                        Http2Error.ENHANCE_YOUR_CALM, streamId);
                hpackDecoder.getHeaderEmitter().setHeaderException(headerException);
            }

            if (hpackDecoder.isHeaderSizeExceeded(headerReadBuffer.position())) {