| // |
| // ======================================================================== |
| // Copyright (c) 1995-2017 Mort Bay Consulting Pty. Ltd. |
| // ------------------------------------------------------------------------ |
| // All rights reserved. This program and the accompanying materials |
| // are made available under the terms of the Eclipse Public License v1.0 |
| // and Apache License v2.0 which accompanies this distribution. |
| // |
| // The Eclipse Public License is available at |
| // http://www.eclipse.org/legal/epl-v10.html |
| // |
| // The Apache License v2.0 is available at |
| // http://www.opensource.org/licenses/apache2.0.php |
| // |
| // You may elect to redistribute this code under either of these licenses. |
| // ======================================================================== |
| // |
| |
| package org.eclipse.jetty.http2.generator; |
| |
| import java.nio.ByteBuffer; |
| |
| import org.eclipse.jetty.http.MetaData; |
| import org.eclipse.jetty.http2.Flags; |
| import org.eclipse.jetty.http2.frames.Frame; |
| import org.eclipse.jetty.http2.frames.FrameType; |
| import org.eclipse.jetty.http2.frames.HeadersFrame; |
| import org.eclipse.jetty.http2.frames.PriorityFrame; |
| import org.eclipse.jetty.http2.hpack.HpackEncoder; |
| import org.eclipse.jetty.io.ByteBufferPool; |
| import org.eclipse.jetty.util.BufferUtil; |
| |
| public class HeadersGenerator extends FrameGenerator |
| { |
| private final HpackEncoder encoder; |
| private final int maxHeaderBlockFragment; |
| private final PriorityGenerator priorityGenerator; |
| |
| public HeadersGenerator(HeaderGenerator headerGenerator, HpackEncoder encoder) |
| { |
| this(headerGenerator, encoder, 0); |
| } |
| |
| public HeadersGenerator(HeaderGenerator headerGenerator, HpackEncoder encoder, int maxHeaderBlockFragment) |
| { |
| super(headerGenerator); |
| this.encoder = encoder; |
| this.maxHeaderBlockFragment = maxHeaderBlockFragment; |
| this.priorityGenerator = new PriorityGenerator(headerGenerator); |
| } |
| |
| @Override |
| public int generate(ByteBufferPool.Lease lease, Frame frame) |
| { |
| HeadersFrame headersFrame = (HeadersFrame)frame; |
| return generateHeaders(lease, headersFrame.getStreamId(), headersFrame.getMetaData(), headersFrame.getPriority(), headersFrame.isEndStream()); |
| } |
| |
| public int generateHeaders(ByteBufferPool.Lease lease, int streamId, MetaData metaData, PriorityFrame priority, boolean endStream) |
| { |
| if (streamId < 0) |
| throw new IllegalArgumentException("Invalid stream id: " + streamId); |
| |
| int flags = Flags.NONE; |
| |
| if (priority != null) |
| flags = Flags.PRIORITY; |
| |
| int maxFrameSize = getMaxFrameSize(); |
| ByteBuffer hpacked = lease.acquire(maxFrameSize, false); |
| BufferUtil.clearToFill(hpacked); |
| encoder.encode(hpacked, metaData); |
| int hpackedLength = hpacked.position(); |
| BufferUtil.flipToFlush(hpacked, 0); |
| |
| // Split into CONTINUATION frames if necessary. |
| if (maxHeaderBlockFragment > 0 && hpackedLength > maxHeaderBlockFragment) |
| { |
| if (endStream) |
| flags |= Flags.END_STREAM; |
| |
| int length = maxHeaderBlockFragment; |
| if (priority != null) |
| length += PriorityFrame.PRIORITY_LENGTH; |
| |
| ByteBuffer header = generateHeader(lease, FrameType.HEADERS, length, flags, streamId); |
| generatePriority(header, priority); |
| BufferUtil.flipToFlush(header, 0); |
| lease.append(header, true); |
| hpacked.limit(maxHeaderBlockFragment); |
| lease.append(hpacked.slice(), false); |
| |
| int totalLength = Frame.HEADER_LENGTH + length; |
| |
| int position = maxHeaderBlockFragment; |
| int limit = position + maxHeaderBlockFragment; |
| while (limit < hpackedLength) |
| { |
| hpacked.position(position).limit(limit); |
| header = generateHeader(lease, FrameType.CONTINUATION, maxHeaderBlockFragment, Flags.NONE, streamId); |
| BufferUtil.flipToFlush(header, 0); |
| lease.append(header, true); |
| lease.append(hpacked.slice(), false); |
| position += maxHeaderBlockFragment; |
| limit += maxHeaderBlockFragment; |
| totalLength += Frame.HEADER_LENGTH + maxHeaderBlockFragment; |
| } |
| |
| hpacked.position(position).limit(hpackedLength); |
| header = generateHeader(lease, FrameType.CONTINUATION, hpacked.remaining(), Flags.END_HEADERS, streamId); |
| BufferUtil.flipToFlush(header, 0); |
| lease.append(header, true); |
| lease.append(hpacked, true); |
| totalLength += Frame.HEADER_LENGTH + hpacked.remaining(); |
| |
| return totalLength; |
| } |
| else |
| { |
| flags |= Flags.END_HEADERS; |
| if (endStream) |
| flags |= Flags.END_STREAM; |
| |
| int length = hpackedLength; |
| if (priority != null) |
| length += PriorityFrame.PRIORITY_LENGTH; |
| |
| ByteBuffer header = generateHeader(lease, FrameType.HEADERS, length, flags, streamId); |
| generatePriority(header, priority); |
| BufferUtil.flipToFlush(header, 0); |
| lease.append(header, true); |
| lease.append(hpacked, true); |
| |
| return Frame.HEADER_LENGTH + length; |
| } |
| } |
| |
| private void generatePriority(ByteBuffer header, PriorityFrame priority) |
| { |
| if (priority != null) |
| { |
| priorityGenerator.generatePriorityBody(header, priority.getStreamId(), |
| priority.getParentStreamId(), priority.getWeight(), priority.isExclusive()); |
| } |
| } |
| } |