| // |
| // ======================================================================== |
| // 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.websocket.common.extensions.fragment; |
| |
| |
| import java.nio.ByteBuffer; |
| import java.util.Queue; |
| |
| import org.eclipse.jetty.util.ConcurrentArrayQueue; |
| import org.eclipse.jetty.util.IteratingCallback; |
| import org.eclipse.jetty.util.log.Log; |
| import org.eclipse.jetty.util.log.Logger; |
| import org.eclipse.jetty.websocket.api.BatchMode; |
| import org.eclipse.jetty.websocket.api.WriteCallback; |
| import org.eclipse.jetty.websocket.api.extensions.ExtensionConfig; |
| import org.eclipse.jetty.websocket.api.extensions.Frame; |
| import org.eclipse.jetty.websocket.common.OpCode; |
| import org.eclipse.jetty.websocket.common.extensions.AbstractExtension; |
| import org.eclipse.jetty.websocket.common.frames.DataFrame; |
| |
| /** |
| * Fragment Extension |
| */ |
| public class FragmentExtension extends AbstractExtension |
| { |
| private static final Logger LOG = Log.getLogger(FragmentExtension.class); |
| |
| private final Queue<FrameEntry> entries = new ConcurrentArrayQueue<>(); |
| private final IteratingCallback flusher = new Flusher(); |
| private int maxLength; |
| |
| @Override |
| public String getName() |
| { |
| return "fragment"; |
| } |
| |
| @Override |
| public void incomingFrame(Frame frame) |
| { |
| nextIncomingFrame(frame); |
| } |
| |
| @Override |
| public void outgoingFrame(Frame frame, WriteCallback callback, BatchMode batchMode) |
| { |
| ByteBuffer payload = frame.getPayload(); |
| int length = payload != null ? payload.remaining() : 0; |
| if (OpCode.isControlFrame(frame.getOpCode()) || maxLength <= 0 || length <= maxLength) |
| { |
| nextOutgoingFrame(frame, callback, batchMode); |
| return; |
| } |
| |
| FrameEntry entry = new FrameEntry(frame, callback, batchMode); |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Queuing {}", entry); |
| entries.offer(entry); |
| flusher.iterate(); |
| } |
| |
| @Override |
| public void setConfig(ExtensionConfig config) |
| { |
| super.setConfig(config); |
| maxLength = config.getParameter("maxLength", -1); |
| } |
| |
| private static class FrameEntry |
| { |
| private final Frame frame; |
| private final WriteCallback callback; |
| private final BatchMode batchMode; |
| |
| private FrameEntry(Frame frame, WriteCallback callback, BatchMode batchMode) |
| { |
| this.frame = frame; |
| this.callback = callback; |
| this.batchMode = batchMode; |
| } |
| |
| @Override |
| public String toString() |
| { |
| return frame.toString(); |
| } |
| } |
| |
| private class Flusher extends IteratingCallback implements WriteCallback |
| { |
| private FrameEntry current; |
| private boolean finished = true; |
| |
| @Override |
| protected Action process() throws Exception |
| { |
| if (finished) |
| { |
| current = entries.poll(); |
| LOG.debug("Processing {}", current); |
| if (current == null) |
| return Action.IDLE; |
| fragment(current, true); |
| } |
| else |
| { |
| fragment(current, false); |
| } |
| return Action.SCHEDULED; |
| } |
| |
| private void fragment(FrameEntry entry, boolean first) |
| { |
| Frame frame = entry.frame; |
| ByteBuffer payload = frame.getPayload(); |
| int remaining = payload.remaining(); |
| int length = Math.min(remaining, maxLength); |
| finished = length == remaining; |
| |
| boolean continuation = frame.getType().isContinuation() || !first; |
| DataFrame fragment = new DataFrame(frame, continuation); |
| boolean fin = frame.isFin() && finished; |
| fragment.setFin(fin); |
| |
| int limit = payload.limit(); |
| int newLimit = payload.position() + length; |
| payload.limit(newLimit); |
| ByteBuffer payloadFragment = payload.slice(); |
| payload.limit(limit); |
| fragment.setPayload(payloadFragment); |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Fragmented {}->{}", frame, fragment); |
| payload.position(newLimit); |
| |
| nextOutgoingFrame(fragment, this, entry.batchMode); |
| } |
| |
| @Override |
| protected void onCompleteSuccess() |
| { |
| // This IteratingCallback never completes. |
| } |
| |
| @Override |
| protected void onCompleteFailure(Throwable x) |
| { |
| // This IteratingCallback never fails. |
| // The callback are those provided by WriteCallback (implemented |
| // below) and even in case of writeFailed() we call succeeded(). |
| } |
| |
| @Override |
| public void writeSuccess() |
| { |
| // Notify first then call succeeded(), otherwise |
| // write callbacks may be invoked out of order. |
| notifyCallbackSuccess(current.callback); |
| succeeded(); |
| } |
| |
| @Override |
| public void writeFailed(Throwable x) |
| { |
| // Notify first, the call succeeded() to drain the queue. |
| // We don't want to call failed(x) because that will put |
| // this flusher into a final state that cannot be exited, |
| // and the failure of a frame may not mean that the whole |
| // connection is now invalid. |
| notifyCallbackFailure(current.callback, x); |
| succeeded(); |
| } |
| |
| private void notifyCallbackSuccess(WriteCallback callback) |
| { |
| try |
| { |
| if (callback != null) |
| callback.writeSuccess(); |
| } |
| catch (Throwable x) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Exception while notifying success of callback " + callback, x); |
| } |
| } |
| |
| private void notifyCallbackFailure(WriteCallback callback, Throwable failure) |
| { |
| try |
| { |
| if (callback != null) |
| callback.writeFailed(failure); |
| } |
| catch (Throwable x) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Exception while notifying failure of callback " + callback, x); |
| } |
| } |
| } |
| } |