Reduce multi-level buffered streams in transport code

[jgit/MarioXXX.git] / org.eclipse.jgit / src / org / eclipse / jgit / transport / BasePackPushConnection.java

/*
 * Copyright (C) 2008, Marek Zawirski <marek.zawirski@gmail.com>
 * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials provided
 *   with the distribution.
 *
 * - Neither the name of the Eclipse Foundation, Inc. nor the
 *   names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior
 *   written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.eclipse.jgit.transport;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Map;

import org.eclipse.jgit.errors.NoRemoteRepositoryException;
import org.eclipse.jgit.errors.NotSupportedException;
import org.eclipse.jgit.errors.PackProtocolException;
import org.eclipse.jgit.errors.TransportException;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.PackWriter;
import org.eclipse.jgit.lib.ProgressMonitor;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.transport.RemoteRefUpdate.Status;

/**
 * Push implementation using the native Git pack transfer service.
 * <p>
 * This is the canonical implementation for transferring objects to the remote
 * repository from the local repository by talking to the 'git-receive-pack'
 * service. Objects are packed on the local side into a pack file and then sent
 * to the remote repository.
 * <p>
 * This connection requires only a bi-directional pipe or socket, and thus is
 * easily wrapped up into a local process pipe, anonymous TCP socket, or a
 * command executed through an SSH tunnel.
 * <p>
 * This implementation honors {@link Transport#isPushThin()} option.
 * <p>
 * Concrete implementations should just call
 * {@link #init(java.io.InputStream, java.io.OutputStream)} and
 * {@link #readAdvertisedRefs()} methods in constructor or before any use. They
 * should also handle resources releasing in {@link #close()} method if needed.
 */
class BasePackPushConnection extends BasePackConnection implements
                PushConnection {
        static final String CAPABILITY_REPORT_STATUS = "report-status";

        static final String CAPABILITY_DELETE_REFS = "delete-refs";

        static final String CAPABILITY_OFS_DELTA = "ofs-delta";

        static final String CAPABILITY_SIDE_BAND_64K = "side-band-64k";

        private final boolean thinPack;

        private boolean capableDeleteRefs;

        private boolean capableReport;

        private boolean capableSideBand;

        private boolean capableOfsDelta;

        private boolean sentCommand;

        private boolean writePack;

        /** Time in milliseconds spent transferring the pack data. */
        private long packTransferTime;

        BasePackPushConnection(final PackTransport packTransport) {
                super(packTransport);
                thinPack = transport.isPushThin();
        }

        public void push(final ProgressMonitor monitor,
                        final Map<String, RemoteRefUpdate> refUpdates)
                        throws TransportException {
                markStartedOperation();
                doPush(monitor, refUpdates);
        }

        @Override
        protected TransportException noRepository() {
                // Sadly we cannot tell the "invalid URI" case from "push not allowed".
                // Opening a fetch connection can help us tell the difference, as any
                // useful repository is going to support fetch if it also would allow
                // push. So if fetch throws NoRemoteRepositoryException we know the
                // URI is wrong. Otherwise we can correctly state push isn't allowed
                // as the fetch connection opened successfully.
                //
                try {
                        transport.openFetch().close();
                } catch (NotSupportedException e) {
                        // Fall through.
                } catch (NoRemoteRepositoryException e) {
                        // Fetch concluded the repository doesn't exist.
                        //
                        return e;
                } catch (TransportException e) {
                        // Fall through.
                }
                return new TransportException(uri, "push not permitted");
        }

        protected void doPush(final ProgressMonitor monitor,
                        final Map<String, RemoteRefUpdate> refUpdates)
                        throws TransportException {
                try {
                        writeCommands(refUpdates.values(), monitor);
                        if (writePack)
                                writePack(refUpdates, monitor);
                        if (sentCommand) {
                                if (capableReport)
                                        readStatusReport(refUpdates);
                                if (capableSideBand) {
                                        // Ensure the data channel is at EOF, so we know we have
                                        // read all side-band data from all channels and have a
                                        // complete copy of the messages (if any) buffered from
                                        // the other data channels.
                                        //
                                        int b = in.read();
                                        if (0 <= b)
                                                throw new TransportException(uri, "expected EOF;"
                                                                + " received '" + (char) b + "' instead");
                                }
                        }
                } catch (TransportException e) {
                        throw e;
                } catch (Exception e) {
                        throw new TransportException(uri, e.getMessage(), e);
                } finally {
                        close();
                }
        }

        private void writeCommands(final Collection<RemoteRefUpdate> refUpdates,
                        final ProgressMonitor monitor) throws IOException {
                final String capabilities = enableCapabilities(monitor);
                for (final RemoteRefUpdate rru : refUpdates) {
                        if (!capableDeleteRefs && rru.isDelete()) {
                                rru.setStatus(Status.REJECTED_NODELETE);
                                continue;
                        }

                        final StringBuilder sb = new StringBuilder();
                        final Ref advertisedRef = getRef(rru.getRemoteName());
                        final ObjectId oldId = (advertisedRef == null ? ObjectId.zeroId()
                                        : advertisedRef.getObjectId());
                        sb.append(oldId.name());
                        sb.append(' ');
                        sb.append(rru.getNewObjectId().name());
                        sb.append(' ');
                        sb.append(rru.getRemoteName());
                        if (!sentCommand) {
                                sentCommand = true;
                                sb.append(capabilities);
                        }

                        pckOut.writeString(sb.toString());
                        rru.setStatus(Status.AWAITING_REPORT);
                        if (!rru.isDelete())
                                writePack = true;
                }

                if (monitor.isCancelled())
                        throw new TransportException(uri, "push cancelled");
                pckOut.end();
                outNeedsEnd = false;
        }

        private String enableCapabilities(final ProgressMonitor monitor) {
                final StringBuilder line = new StringBuilder();
                capableReport = wantCapability(line, CAPABILITY_REPORT_STATUS);
                capableDeleteRefs = wantCapability(line, CAPABILITY_DELETE_REFS);
                capableOfsDelta = wantCapability(line, CAPABILITY_OFS_DELTA);

                capableSideBand = wantCapability(line, CAPABILITY_SIDE_BAND_64K);
                if (capableSideBand) {
                        in = new SideBandInputStream(in, monitor, getMessageWriter());
                        pckIn = new PacketLineIn(in);
                }

                if (line.length() > 0)
                        line.setCharAt(0, '\0');
                return line.toString();
        }

        private void writePack(final Map<String, RemoteRefUpdate> refUpdates,
                        final ProgressMonitor monitor) throws IOException {
                final PackWriter writer = new PackWriter(local, monitor);
                final ArrayList<ObjectId> remoteObjects = new ArrayList<ObjectId>(
                                getRefs().size());
                final ArrayList<ObjectId> newObjects = new ArrayList<ObjectId>(
                                refUpdates.size());

                for (final Ref r : getRefs())
                        remoteObjects.add(r.getObjectId());
                remoteObjects.addAll(additionalHaves);
                for (final RemoteRefUpdate r : refUpdates.values()) {
                        if (!ObjectId.zeroId().equals(r.getNewObjectId()))
                                newObjects.add(r.getNewObjectId());
                }

                writer.setThin(thinPack);
                writer.setDeltaBaseAsOffset(capableOfsDelta);
                writer.preparePack(newObjects, remoteObjects);
                final long start = System.currentTimeMillis();
                writer.writePack(out);
                out.flush();
                packTransferTime = System.currentTimeMillis() - start;
        }

        private void readStatusReport(final Map<String, RemoteRefUpdate> refUpdates)
                        throws IOException {
                final String unpackLine = readStringLongTimeout();
                if (!unpackLine.startsWith("unpack "))
                        throw new PackProtocolException(uri, "unexpected report line: "
                                        + unpackLine);
                final String unpackStatus = unpackLine.substring("unpack ".length());
                if (!unpackStatus.equals("ok"))
                        throw new TransportException(uri,
                                        "error occurred during unpacking on the remote end: "
                                                        + unpackStatus);

                String refLine;
                while ((refLine = pckIn.readString()) != PacketLineIn.END) {
                        boolean ok = false;
                        int refNameEnd = -1;
                        if (refLine.startsWith("ok ")) {
                                ok = true;
                                refNameEnd = refLine.length();
                        } else if (refLine.startsWith("ng ")) {
                                ok = false;
                                refNameEnd = refLine.indexOf(" ", 3);
                        }
                        if (refNameEnd == -1)
                                throw new PackProtocolException(uri
                                                + ": unexpected report line: " + refLine);
                        final String refName = refLine.substring(3, refNameEnd);
                        final String message = (ok ? null : refLine
                                        .substring(refNameEnd + 1));

                        final RemoteRefUpdate rru = refUpdates.get(refName);
                        if (rru == null)
                                throw new PackProtocolException(uri
                                                + ": unexpected ref report: " + refName);
                        if (ok) {
                                rru.setStatus(Status.OK);
                        } else {
                                rru.setStatus(Status.REJECTED_OTHER_REASON);
                                rru.setMessage(message);
                        }
                }
                for (final RemoteRefUpdate rru : refUpdates.values()) {
                        if (rru.getStatus() == Status.AWAITING_REPORT)
                                throw new PackProtocolException(uri
                                                + ": expected report for ref " + rru.getRemoteName()
                                                + " not received");
                }
        }

        private String readStringLongTimeout() throws IOException {
                if (timeoutIn == null)
                        return pckIn.readString();

                // The remote side may need a lot of time to choke down the pack
                // we just sent them. There may be many deltas that need to be
                // resolved by the remote. Its hard to say how long the other
                // end is going to be silent. Taking 10x the configured timeout
                // or the time spent transferring the pack, whichever is larger,
                // gives the other side some reasonable window to process the data,
                // but this is just a wild guess.
                //
                final int oldTimeout = timeoutIn.getTimeout();
                final int sendTime = (int) Math.min(packTransferTime, 28800000L);
                try {
                        timeoutIn.setTimeout(10 * Math.max(sendTime, oldTimeout));
                        return pckIn.readString();
                } finally {
                        timeoutIn.setTimeout(oldTimeout);
                }
        }
}