Method readHeadersFrame

java/org/apache/coyote/http2/Http2Parser.java:236–305

(int streamId, int flags, int payloadSize, ByteBuffer buffer)

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

        headersEndStream = Flags.isEndOfStream(flags);

        try {
            hpackDecoder.setHeaderEmitter(output.headersStart(streamId, headersEndStream));
        } catch (StreamException se) {
            swallowPayload(streamId, FrameType.HEADERS.getId(), payloadSize, false, buffer);
            throw se;
        }

        int padLength = 0;
        boolean padding = Flags.hasPadding(flags);
        boolean priority = Flags.hasPriority(flags);
        int optionalLen = 0;
        if (padding) {
            optionalLen = 1;
        }
        if (priority) {
            optionalLen += 5;
        }

        // Frame is too small to contain mandatory frame data (for the given flags)
        if (payloadSize < optionalLen) {
            throw new ConnectionException(sm.getString("http2Parser.processFrame.insufficientPayload",connectionId,
                    Integer.toString(streamId), Integer.toString(FrameType.HEADERS.getId()),
                    Integer.toString(flags), Integer.toString(payloadSize)), Http2Error.FRAME_SIZE_ERROR);
        }

        if (optionalLen > 0) {
            byte[] optional = new byte[optionalLen];
            if (buffer == null) {
                input.fill(true, optional);
            } else {
                buffer.get(optional);
            }
            /*
             * The optional padLength byte and priority bytes (if any) don't count towards the payload size when
             * comparing payload size to padLength as required by RFC 9113, section 6.2.
             */
            payloadSize -= optionalLen;

            if (padding) {
                padLength = ByteUtil.getOneByte(optional, 0);
                if (padLength >= payloadSize) {
                    throw new ConnectionException(sm.getString("http2Parser.processFrame.tooMuchPadding", connectionId,
                            Integer.toString(streamId), Integer.toString(padLength), Integer.toString(payloadSize)),
                            Http2Error.PROTOCOL_ERROR);
                }
            }
            // The padding does not count towards the size of payload that is read below.
            payloadSize -= padLength;

            // Any RFC 7450 priority data was read into the byte[] optional above. It is ignored.
        }

        readHeaderPayload(streamId, payloadSize, buffer);