RefDirectoryUpdate.java

/*
 * Copyright (C) 2009-2010, Google Inc.
 * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package org.eclipse.jgit.internal.storage.file;

import static org.eclipse.jgit.lib.Constants.encode;

import java.io.IOException;

import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.RefUpdate;
import org.eclipse.jgit.lib.ReflogEntry;
import org.eclipse.jgit.lib.Repository;

/** Updates any reference stored by {@link RefDirectory}. */
class RefDirectoryUpdate extends RefUpdate {
    private final RefDirectory database;

    private boolean shouldDeref;
    private LockFile lock;

    RefDirectoryUpdate(RefDirectory r, Ref ref) {
        super(ref);
        database = r;
    }

    /** {@inheritDoc} */
    @Override
    protected RefDirectory getRefDatabase() {
        return database;
    }

    /** {@inheritDoc} */
    @Override
    protected Repository getRepository() {
        return database.getRepository();
    }

    /** {@inheritDoc} */
    @Override
    protected boolean tryLock(boolean deref) throws IOException {
        shouldDeref = deref;
        Ref dst = getRef();
        if (deref)
            dst = dst.getLeaf();
        String name = dst.getName();
        lock = new LockFile(database.fileFor(name));
        if (lock.lock()) {
            dst = database.findRef(name);
            setOldObjectId(dst != null ? dst.getObjectId() : null);
            return true;
        }
        return false;
    }

    /** {@inheritDoc} */
    @Override
    protected void unlock() {
        if (lock != null) {
            lock.unlock();
            lock = null;
        }
    }

    /** {@inheritDoc} */
    @Override
    protected Result doUpdate(Result status) throws IOException {
        WriteConfig wc = database.getRepository().getConfig()
                .get(WriteConfig.KEY);

        lock.setFSync(wc.getFSyncRefFiles());
        lock.setNeedStatInformation(true);
        lock.write(getNewObjectId());

        String msg = getRefLogMessage();
        if (msg != null) {
            if (isRefLogIncludingResult()) {
                String strResult = toResultString(status);
                if (strResult != null) {
                    if (msg.length() > 0)
                        msg = msg + ": " + strResult; //$NON-NLS-1$
                    else
                        msg = strResult;
                }
            }
            database.log(isForceRefLog(), this, msg, shouldDeref);
        }
        if (!lock.commit())
            return Result.LOCK_FAILURE;
        database.stored(this, lock.getCommitSnapshot());
        return status;
    }

    private String toResultString(Result status) {
        switch (status) {
        case FORCED:
            return ReflogEntry.PREFIX_FORCED_UPDATE;
        case FAST_FORWARD:
            return ReflogEntry.PREFIX_FAST_FORWARD;
        case NEW:
            return ReflogEntry.PREFIX_CREATED;
        default:
            return null;
        }
    }

    /** {@inheritDoc} */
    @Override
    protected Result doDelete(Result status) throws IOException {
        if (getRef().getStorage() != Ref.Storage.NEW)
            database.delete(this);
        return status;
    }

    /** {@inheritDoc} */
    @Override
    protected Result doLink(String target) throws IOException {
        WriteConfig wc = database.getRepository().getConfig()
                .get(WriteConfig.KEY);

        lock.setFSync(wc.getFSyncRefFiles());
        lock.setNeedStatInformation(true);
        lock.write(encode(RefDirectory.SYMREF + target + '\n'));

        String msg = getRefLogMessage();
        if (msg != null)
            database.log(isForceRefLog(), this, msg, false);
        if (!lock.commit())
            return Result.LOCK_FAILURE;
        database.storedSymbolicRef(this, lock.getCommitSnapshot(), target);

        if (getRef().getStorage() == Ref.Storage.NEW)
            return Result.NEW;
        return Result.FORCED;
    }
}