VerifyReftable.java

/*
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package org.eclipse.jgit.pgm.debug;

import java.io.FileInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;

import org.eclipse.jgit.internal.storage.io.BlockSource;
import org.eclipse.jgit.internal.storage.reftable.RefCursor;
import org.eclipse.jgit.internal.storage.reftable.ReftableReader;
import org.eclipse.jgit.lib.AnyObjectId;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.RefComparator;
import org.eclipse.jgit.lib.TextProgressMonitor;
import org.eclipse.jgit.pgm.Command;
import org.eclipse.jgit.pgm.TextBuiltin;
import org.kohsuke.args4j.Argument;

@Command
class VerifyReftable extends TextBuiltin {
    private static final long SEED1 = 0xaba8bb4de4caf86cL;
    private static final long SEED2 = 0x28bb5c25ad43ecb5L;

    @Argument(index = 0)
    private String lsRemotePath;

    @Argument(index = 1)
    private String reftablePath;

    /** {@inheritDoc} */
    @Override
    protected void run() throws Exception {
        List<Ref> refs = WriteReftable.readRefs(lsRemotePath);

        try (FileInputStream in = new FileInputStream(reftablePath);
                BlockSource src = BlockSource.from(in);
                ReftableReader reader = new ReftableReader(src)) {
            scan(refs, reader);
            seek(refs, reader);
            byId(refs, reader);
        }
    }

    @SuppressWarnings("nls")
    private void scan(List<Ref> refs, ReftableReader reader)
            throws IOException {
        errw.print(String.format("%-20s", "sequential scan..."));
        errw.flush();
        try (RefCursor rc = reader.allRefs()) {
            for (Ref exp : refs) {
                verify(exp, rc);
            }
            if (rc.next()) {
                throw die("expected end of table");
            }
        }
        errw.println(" OK");
    }

    @SuppressWarnings("nls")
    private void seek(List<Ref> refs, ReftableReader reader)
            throws IOException {
        List<Ref> rnd = new ArrayList<>(refs);
        Collections.shuffle(rnd, new Random(SEED1));

        TextProgressMonitor pm = new TextProgressMonitor(errw);
        pm.beginTask("random seek", rnd.size());
        for (Ref exp : rnd) {
            try (RefCursor rc = reader.seekRef(exp.getName())) {
                verify(exp, rc);
                if (rc.next()) {
                    throw die("should not have ref after " + exp.getName());
                }
            }
            pm.update(1);
        }
        pm.endTask();
    }

    @SuppressWarnings("nls")
    private void byId(List<Ref> refs, ReftableReader reader)
            throws IOException {
        Map<ObjectId, List<Ref>> want = groupById(refs);
        List<List<Ref>> rnd = new ArrayList<>(want.values());
        Collections.shuffle(rnd, new Random(SEED2));

        TextProgressMonitor pm = new TextProgressMonitor(errw);
        pm.beginTask("byObjectId", rnd.size());
        for (List<Ref> exp : rnd) {
            Collections.sort(exp, RefComparator.INSTANCE);
            ObjectId id = exp.get(0).getObjectId();
            try (RefCursor rc = reader.byObjectId(id)) {
                for (Ref r : exp) {
                    verify(r, rc);
                }
            }
            pm.update(1);
        }
        pm.endTask();
    }

    private static Map<ObjectId, List<Ref>> groupById(List<Ref> refs) {
        Map<ObjectId, List<Ref>> m = new HashMap<>();
        for (Ref r : refs) {
            ObjectId id = r.getObjectId();
            if (id != null) {
                List<Ref> c = m.get(id);
                if (c == null) {
                    c = new ArrayList<>(2);
                    m.put(id, c);
                }
                c.add(r);
            }
        }
        return m;
    }

    @SuppressWarnings("nls")
    private void verify(Ref exp, RefCursor rc) throws IOException {
        if (!rc.next()) {
            throw die("ended before " + exp.getName());
        }

        Ref act = rc.getRef();
        if (!exp.getName().equals(act.getName())) {
            throw die(String.format("expected %s, found %s",
                    exp.getName(),
                    act.getName()));
        }

        if (exp.isSymbolic()) {
            if (!act.isSymbolic()) {
                throw die("expected " + act.getName() + " to be symbolic");
            }
            if (!exp.getTarget().getName().equals(act.getTarget().getName())) {
                throw die(String.format("expected %s to be %s, found %s",
                        exp.getName(),
                        exp.getLeaf().getName(),
                        act.getLeaf().getName()));
            }
            return;
        }

        if (!AnyObjectId.equals(exp.getObjectId(), act.getObjectId())) {
            throw die(String.format("expected %s to be %s, found %s",
                    exp.getName(),
                    id(exp.getObjectId()),
                    id(act.getObjectId())));
        }

        if (exp.getPeeledObjectId() != null
                && !AnyObjectId.equals(exp.getPeeledObjectId(), act.getPeeledObjectId())) {
            throw die(String.format("expected %s to be %s, found %s",
                    exp.getName(),
                    id(exp.getPeeledObjectId()),
                    id(act.getPeeledObjectId())));
        }
    }

    @SuppressWarnings("nls")
    private static String id(ObjectId id) {
        return id != null ? id.name() : "<null>";
    }
}