Dissolve gerrit-server top-level directory

Change-Id: I538512dfe0f1bea774c01fdd45fa410a45634011

java/com/google/gerrit/server/util/CommitMessageUtil.java

@@ -0,0 +1,40 @@
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.common.base.Strings;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+
+/** Utility functions to manipulate commit messages. */
+public class CommitMessageUtil {
+
+  private CommitMessageUtil() {}
+
+  /**
+   * Checks for null or empty commit messages and appends a newline character to the commit message.
+   *
+   * @throws BadRequestException if the commit message is null or empty
+   * @returns the trimmed message with a trailing newline character
+   */
+  public static String checkAndSanitizeCommitMessage(String commitMessage)
+      throws BadRequestException {
+    String wellFormedMessage = Strings.nullToEmpty(commitMessage).trim();
+    if (wellFormedMessage.isEmpty()) {
+      throw new BadRequestException("Commit message cannot be null or empty");
+    }
+    wellFormedMessage = wellFormedMessage + "\n";
+    return wellFormedMessage;
+  }
+}

java/com/google/gerrit/server/util/FallbackRequestContext.java

@@ -0,0 +1,53 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.AnonymousUser;
+import com.google.gerrit.server.CurrentUser;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.ProvisionException;
+import com.google.inject.Singleton;
+
+/**
+ * The default RequestContext to use when not in a request scope e.g. ThreadLocalRequestContext is
+ * not set.
+ */
+@Singleton
+public class FallbackRequestContext implements RequestContext {
+
+  private final AnonymousUser user;
+
+  @Inject
+  FallbackRequestContext(AnonymousUser user) {
+    this.user = user;
+  }
+
+  @Override
+  public CurrentUser getUser() {
+    return user;
+  }
+
+  @Override
+  public Provider<ReviewDb> getReviewDbProvider() {
+    return new Provider<ReviewDb>() {
+      @Override
+      public ReviewDb get() {
+        throw new ProvisionException("Automatic ReviewDb only available in request scope");
+      }
+    };
+  }
+}

java/com/google/gerrit/server/util/GuiceRequestScopePropagator.java

@@ -0,0 +1,75 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.server.RemotePeer;
+import com.google.gerrit.server.config.CanonicalWebUrl;
+import com.google.gerrit.server.config.RequestScopedReviewDbProvider;
+import com.google.inject.Inject;
+import com.google.inject.Key;
+import com.google.inject.Provider;
+import com.google.inject.servlet.ServletScopes;
+import com.google.inject.util.Providers;
+import com.google.inject.util.Types;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.net.SocketAddress;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.Callable;
+
+/** Propagator for Guice's built-in servlet scope. */
+public class GuiceRequestScopePropagator extends RequestScopePropagator {
+
+  private final String url;
+  private final SocketAddress peer;
+
+  @Inject
+  GuiceRequestScopePropagator(
+      @CanonicalWebUrl @Nullable Provider<String> urlProvider,
+      @RemotePeer Provider<SocketAddress> remotePeerProvider,
+      ThreadLocalRequestContext local,
+      Provider<RequestScopedReviewDbProvider> dbProviderProvider) {
+    super(ServletScopes.REQUEST, local, dbProviderProvider);
+    this.url = urlProvider != null ? urlProvider.get() : null;
+    this.peer = remotePeerProvider.get();
+  }
+
+  /** @see RequestScopePropagator#wrap(Callable) */
+  // ServletScopes#continueRequest is deprecated, but it's not obvious their
+  // recommended replacement is an appropriate drop-in solution; see
+  // https://gerrit-review.googlesource.com/83971
+  @SuppressWarnings("deprecation")
+  @Override
+  protected <T> Callable<T> wrapImpl(Callable<T> callable) {
+    Map<Key<?>, Object> seedMap = new HashMap<>();
+
+    // Request scopes appear to use specific keys in their map, instead of only
+    // providers. Add bindings for both the key to the instance directly and the
+    // provider to the instance to be safe.
+    seedMap.put(Key.get(typeOfProvider(String.class), CanonicalWebUrl.class), Providers.of(url));
+    seedMap.put(Key.get(String.class, CanonicalWebUrl.class), url);
+
+    seedMap.put(Key.get(typeOfProvider(SocketAddress.class), RemotePeer.class), Providers.of(peer));
+    seedMap.put(Key.get(SocketAddress.class, RemotePeer.class), peer);
+
+    return ServletScopes.continueRequest(callable, seedMap);
+  }
+
+  private ParameterizedType typeOfProvider(Type type) {
+    return Types.newParameterizedType(Provider.class, type);
+  }
+}

java/com/google/gerrit/server/util/HostPlatform.java

@@ -0,0 +1,46 @@
+// Copyright (C) 2009 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
+public final class HostPlatform {
+  private static final boolean win32 = compute("windows");
+  private static final boolean mac = compute("mac");
+
+  /** @return true if this JVM is running on a Windows platform. */
+  public static boolean isWin32() {
+    return win32;
+  }
+
+  public static boolean isMac() {
+    return mac;
+  }
+
+  private static boolean compute(String platform) {
+    final String osDotName =
+        AccessController.doPrivileged(
+            new PrivilegedAction<String>() {
+              @Override
+              public String run() {
+                return System.getProperty("os.name");
+              }
+            });
+    return osDotName != null && osDotName.toLowerCase().contains(platform);
+  }
+
+  private HostPlatform() {}
+}

java/com/google/gerrit/server/util/IdGenerator.java

@@ -0,0 +1,99 @@
+// Copyright (C) 2009 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import java.util.Random;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/** Simple class to produce 4 billion keys randomly distributed. */
+@Singleton
+public class IdGenerator {
+  /** Format an id created by this class as a hex string. */
+  public static String format(int id) {
+    final char[] r = new char[8];
+    for (int p = 7; 0 <= p; p--) {
+      final int h = id & 0xf;
+      r[p] = h < 10 ? (char) ('0' + h) : (char) ('a' + (h - 10));
+      id >>= 4;
+    }
+    return new String(r);
+  }
+
+  private final AtomicInteger gen;
+
+  @Inject
+  IdGenerator() {
+    gen = new AtomicInteger(new Random().nextInt());
+  }
+
+  /** Produce the next identifier. */
+  public int next() {
+    return mix(gen.getAndIncrement());
+  }
+
+  private static final int salt = 0x9e3779b9;
+
+  static int mix(int in) {
+    return mix(salt, in);
+  }
+
+  /** A very simple bit permutation to mask a simple incrementer. */
+  public static int mix(int salt, int in) {
+    short v0 = hi16(in);
+    short v1 = lo16(in);
+    v0 += ((v1 << 2) + 0 ^ v1) + (salt ^ (v1 >>> 3)) + 1;
+    v1 += ((v0 << 2) + 2 ^ v0) + (salt ^ (v0 >>> 3)) + 3;
+    return result(v0, v1);
+  }
+
+  /* For testing only. */
+  static int unmix(int in) {
+    short v0 = hi16(in);
+    short v1 = lo16(in);
+    v1 -= ((v0 << 2) + 2 ^ v0) + (salt ^ (v0 >>> 3)) + 3;
+    v0 -= ((v1 << 2) + 0 ^ v1) + (salt ^ (v1 >>> 3)) + 1;
+    return result(v0, v1);
+  }
+
+  private static short hi16(int in) {
+    return (short)
+        ( //
+        ((in >>> 24 & 0xff))
+            | //
+            ((in >>> 16 & 0xff) << 8) //
+        );
+  }
+
+  private static short lo16(int in) {
+    return (short)
+        ( //
+        ((in >>> 8 & 0xff))
+            | //
+            ((in & 0xff) << 8) //
+        );
+  }
+
+  private static int result(short v0, short v1) {
+    return ((v0 & 0xff) << 24)
+        | //
+        (((v0 >>> 8) & 0xff) << 16)
+        | //
+        ((v1 & 0xff) << 8)
+        | //
+        ((v1 >>> 8) & 0xff);
+  }
+}

java/com/google/gerrit/server/util/LabelVote.java

@@ -0,0 +1,91 @@
+// Copyright (C) 2013 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.auto.value.AutoValue;
+import com.google.common.base.Strings;
+import com.google.gerrit.common.data.LabelType;
+
+/** A single vote on a label, consisting of a label name and a value. */
+@AutoValue
+public abstract class LabelVote {
+  public static LabelVote parse(String text) {
+    checkArgument(!Strings.isNullOrEmpty(text), "Empty label vote");
+    if (text.charAt(0) == '-') {
+      return create(text.substring(1), (short) 0);
+    }
+    short sign = 0;
+    int i;
+    for (i = text.length() - 1; i >= 0; i--) {
+      int c = text.charAt(i);
+      if (c == '-') {
+        sign = (short) -1;
+        break;
+      } else if (c == '+') {
+        sign = (short) 1;
+        break;
+      } else if (!('0' <= c && c <= '9')) {
+        break;
+      }
+    }
+    if (sign == 0) {
+      return create(text, (short) 1);
+    }
+    return create(text.substring(0, i), (short) (sign * Short.parseShort(text.substring(i + 1))));
+  }
+
+  public static LabelVote parseWithEquals(String text) {
+    checkArgument(!Strings.isNullOrEmpty(text), "Empty label vote");
+    int e = text.lastIndexOf('=');
+    checkArgument(e >= 0, "Label vote missing '=': %s", text);
+    return create(text.substring(0, e), Short.parseShort(text.substring(e + 1)));
+  }
+
+  public static StringBuilder appendTo(StringBuilder sb, String label, short value) {
+    if (value == (short) 0) {
+      return sb.append('-').append(label);
+    } else if (value < 0) {
+      return sb.append(label).append(value);
+    }
+    return sb.append(label).append('+').append(value);
+  }
+
+  public static LabelVote create(String label, short value) {
+    return new AutoValue_LabelVote(LabelType.checkNameInternal(label), value);
+  }
+
+  public abstract String label();
+
+  public abstract short value();
+
+  public String format() {
+    // Max short string length is "-32768".length() == 6.
+    return appendTo(new StringBuilder(label().length() + 6), label(), value()).toString();
+  }
+
+  public String formatWithEquals() {
+    if (value() <= (short) 0) {
+      return label() + '=' + value();
+    }
+    return label() + "=+" + value();
+  }
+
+  @Override
+  public String toString() {
+    return format();
+  }
+}

java/com/google/gerrit/server/util/MagicBranch.java

@@ -0,0 +1,115 @@
+// Copyright (C) 2011 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.common.data.Capable;
+import com.google.gerrit.reviewdb.client.Project;
+import java.io.IOException;
+import java.util.Map;
+import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.lib.Repository;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public final class MagicBranch {
+  private static final Logger log = LoggerFactory.getLogger(MagicBranch.class);
+
+  public static final String NEW_CHANGE = "refs/for/";
+  // TODO(xchangcheng): remove after 'repo' supports private/wip changes.
+  public static final String NEW_DRAFT_CHANGE = "refs/drafts/";
+  // TODO(xchangcheng): remove after migrating tools which are using this magic branch.
+  public static final String NEW_PUBLISH_CHANGE = "refs/publish/";
+
+  /** Extracts the destination from a ref name */
+  public static String getDestBranchName(String refName) {
+    String magicBranch = NEW_CHANGE;
+    if (refName.startsWith(NEW_DRAFT_CHANGE)) {
+      magicBranch = NEW_DRAFT_CHANGE;
+    } else if (refName.startsWith(NEW_PUBLISH_CHANGE)) {
+      magicBranch = NEW_PUBLISH_CHANGE;
+    }
+    return refName.substring(magicBranch.length());
+  }
+
+  /** Checks if the supplied ref name is a magic branch */
+  public static boolean isMagicBranch(String refName) {
+    return refName.startsWith(NEW_DRAFT_CHANGE)
+        || refName.startsWith(NEW_PUBLISH_CHANGE)
+        || refName.startsWith(NEW_CHANGE);
+  }
+
+  /** Returns the ref name prefix for a magic branch, {@code null} if the branch is not magic */
+  public static String getMagicRefNamePrefix(String refName) {
+    if (refName.startsWith(NEW_DRAFT_CHANGE)) {
+      return NEW_DRAFT_CHANGE;
+    }
+    if (refName.startsWith(NEW_PUBLISH_CHANGE)) {
+      return NEW_PUBLISH_CHANGE;
+    }
+    if (refName.startsWith(NEW_CHANGE)) {
+      return NEW_CHANGE;
+    }
+    return null;
+  }
+
+  /**
+   * Checks if a (magic branch)/branch_name reference exists in the destination repository and only
+   * returns Capable.OK if it does not match any.
+   *
+   * <p>These block the client from being able to even send us a pack file, as it is very unlikely
+   * the user passed the --force flag and the new commit is probably not going to fast-forward the
+   * branch.
+   */
+  public static Capable checkMagicBranchRefs(Repository repo, Project project) {
+    Capable result = checkMagicBranchRef(NEW_CHANGE, repo, project);
+    if (result != Capable.OK) {
+      return result;
+    }
+    result = checkMagicBranchRef(NEW_DRAFT_CHANGE, repo, project);
+    if (result != Capable.OK) {
+      return result;
+    }
+    result = checkMagicBranchRef(NEW_PUBLISH_CHANGE, repo, project);
+    if (result != Capable.OK) {
+      return result;
+    }
+
+    return Capable.OK;
+  }
+
+  private static Capable checkMagicBranchRef(String branchName, Repository repo, Project project) {
+    Map<String, Ref> blockingFors;
+    try {
+      blockingFors = repo.getRefDatabase().getRefs(branchName);
+    } catch (IOException err) {
+      String projName = project.getName();
+      log.warn("Cannot scan refs in '" + projName + "'", err);
+      return new Capable("Server process cannot read '" + projName + "'");
+    }
+    if (!blockingFors.isEmpty()) {
+      String projName = project.getName();
+      log.error(
+          "Repository '"
+              + projName
+              + "' needs the following refs removed to receive changes: "
+              + blockingFors.keySet());
+      return new Capable("One or more " + branchName + " names blocks change upload");
+    }
+
+    return Capable.OK;
+  }
+
+  private MagicBranch() {}
+}

java/com/google/gerrit/server/util/ManualRequestContext.java

@@ -0,0 +1,65 @@
+// Copyright (C) 2015 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gwtorm.server.OrmException;
+import com.google.gwtorm.server.SchemaFactory;
+import com.google.inject.Provider;
+import com.google.inject.util.Providers;
+
+/** Closeable version of a {@link RequestContext} with manually-specified providers. */
+public class ManualRequestContext implements RequestContext, AutoCloseable {
+  private final Provider<CurrentUser> userProvider;
+  private final Provider<ReviewDb> db;
+  private final ThreadLocalRequestContext requestContext;
+  private final RequestContext old;
+
+  public ManualRequestContext(
+      CurrentUser user,
+      SchemaFactory<ReviewDb> schemaFactory,
+      ThreadLocalRequestContext requestContext)
+      throws OrmException {
+    this(Providers.of(user), schemaFactory, requestContext);
+  }
+
+  public ManualRequestContext(
+      Provider<CurrentUser> userProvider,
+      SchemaFactory<ReviewDb> schemaFactory,
+      ThreadLocalRequestContext requestContext)
+      throws OrmException {
+    this.userProvider = userProvider;
+    this.db = Providers.of(schemaFactory.open());
+    this.requestContext = requestContext;
+    old = requestContext.setContext(this);
+  }
+
+  @Override
+  public CurrentUser getUser() {
+    return userProvider.get();
+  }
+
+  @Override
+  public Provider<ReviewDb> getReviewDbProvider() {
+    return db;
+  }
+
+  @Override
+  public void close() {
+    requestContext.setContext(old);
+    db.get().close();
+  }
+}

java/com/google/gerrit/server/util/MostSpecificComparator.java

@@ -0,0 +1,118 @@
+// Copyright (C) 2011 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.common.data.RefConfigSection;
+import com.google.gerrit.server.project.RefPattern;
+import java.util.Comparator;
+import org.apache.commons.lang.StringUtils;
+
+/**
+ * Order the Ref Pattern by the most specific. This sort is done by:
+ *
+ * <ul>
+ *   <li>1 - The minor value of Levenshtein string distance between the branch name and the regex
+ *       string shortest example. A shorter distance is a more specific match.
+ *   <li>2 - Finites first, infinities after.
+ *   <li>3 - Number of transitions. More transitions is more specific.
+ *   <li>4 - Length of the expression text.
+ * </ul>
+ *
+ * Levenshtein distance is a measure of the similarity between two strings. The distance is the
+ * number of deletions, insertions, or substitutions required to transform one string into another.
+ *
+ * <p>For example, if given refs/heads/m* and refs/heads/*, the distances are 5 and 6. It means that
+ * refs/heads/m* is more specific because it's closer to refs/heads/master than refs/heads/*.
+ *
+ * <p>Another example could be refs/heads/* and refs/heads/[a-zA-Z]*, the distances are both 6. Both
+ * are infinite, but refs/heads/[a-zA-Z]* has more transitions, which after all turns it more
+ * specific.
+ */
+public final class MostSpecificComparator implements Comparator<RefConfigSection> {
+  private final String refName;
+
+  public MostSpecificComparator(String refName) {
+    this.refName = refName;
+  }
+
+  @Override
+  public int compare(RefConfigSection a, RefConfigSection b) {
+    return compare(a.getName(), b.getName());
+  }
+
+  public int compare(String pattern1, String pattern2) {
+    int cmp = distance(pattern1) - distance(pattern2);
+    if (cmp == 0) {
+      boolean p1_finite = finite(pattern1);
+      boolean p2_finite = finite(pattern2);
+
+      if (p1_finite && !p2_finite) {
+        cmp = -1;
+      } else if (!p1_finite && p2_finite) {
+        cmp = 1;
+      } else /* if (f1 == f2) */ {
+        cmp = 0;
+      }
+    }
+    if (cmp == 0) {
+      cmp = transitions(pattern2) - transitions(pattern1);
+    }
+    if (cmp == 0) {
+      cmp = pattern2.length() - pattern1.length();
+    }
+    return cmp;
+  }
+
+  private int distance(String pattern) {
+    String example;
+    if (RefPattern.isRE(pattern)) {
+      example = RefPattern.shortestExample(pattern);
+
+    } else if (pattern.endsWith("/*")) {
+      example = pattern;
+
+    } else if (pattern.equals(refName)) {
+      return 0;
+
+    } else {
+      return Math.max(pattern.length(), refName.length());
+    }
+    return StringUtils.getLevenshteinDistance(example, refName);
+  }
+
+  private boolean finite(String pattern) {
+    if (RefPattern.isRE(pattern)) {
+      return RefPattern.toRegExp(pattern).toAutomaton().isFinite();
+
+    } else if (pattern.endsWith("/*")) {
+      return false;
+
+    } else {
+      return true;
+    }
+  }
+
+  private int transitions(String pattern) {
+    if (RefPattern.isRE(pattern)) {
+      return RefPattern.toRegExp(pattern).toAutomaton().getNumberOfTransitions();
+
+    } else if (pattern.endsWith("/*")) {
+      return pattern.length();
+
+    } else {
+      return pattern.length();
+    }
+  }
+}

java/com/google/gerrit/server/util/OneOffRequestContext.java

@@ -0,0 +1,62 @@
+// Copyright (C) 2015 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.reviewdb.client.Account;
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.IdentifiedUser;
+import com.google.gerrit.server.InternalUser;
+import com.google.gwtorm.server.OrmException;
+import com.google.gwtorm.server.SchemaFactory;
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+
+/**
+ * Helper to create one-off request contexts.
+ *
+ * <p>Each call to {@link #open()} opens a new {@link ReviewDb}, so this class should only be used
+ * in a bounded try/finally block.
+ *
+ * <p>The user in the request context is {@link InternalUser} or the {@link IdentifiedUser}
+ * associated to the userId passed as parameter.
+ */
+@Singleton
+public class OneOffRequestContext {
+  private final InternalUser.Factory userFactory;
+  private final SchemaFactory<ReviewDb> schemaFactory;
+  private final ThreadLocalRequestContext requestContext;
+  private final IdentifiedUser.GenericFactory identifiedUserFactory;
+
+  @Inject
+  OneOffRequestContext(
+      InternalUser.Factory userFactory,
+      SchemaFactory<ReviewDb> schemaFactory,
+      ThreadLocalRequestContext requestContext,
+      IdentifiedUser.GenericFactory identifiedUserFactory) {
+    this.userFactory = userFactory;
+    this.schemaFactory = schemaFactory;
+    this.requestContext = requestContext;
+    this.identifiedUserFactory = identifiedUserFactory;
+  }
+
+  public ManualRequestContext open() throws OrmException {
+    return new ManualRequestContext(userFactory.create(), schemaFactory, requestContext);
+  }
+
+  public ManualRequestContext openAs(Account.Id userId) throws OrmException {
+    return new ManualRequestContext(
+        identifiedUserFactory.create(userId), schemaFactory, requestContext);
+  }
+}

java/com/google/gerrit/server/util/PluginLogFile.java

@@ -0,0 +1,59 @@
+// Copyright (C) 2015 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.extensions.events.LifecycleListener;
+import com.google.gerrit.extensions.systemstatus.ServerInformation;
+import org.apache.log4j.AsyncAppender;
+import org.apache.log4j.Layout;
+import org.apache.log4j.LogManager;
+import org.apache.log4j.Logger;
+
+public abstract class PluginLogFile implements LifecycleListener {
+
+  private final SystemLog systemLog;
+  private final ServerInformation serverInfo;
+  private final String logName;
+  private final Layout layout;
+
+  public PluginLogFile(
+      SystemLog systemLog, ServerInformation serverInfo, String logName, Layout layout) {
+    this.systemLog = systemLog;
+    this.serverInfo = serverInfo;
+    this.logName = logName;
+    this.layout = layout;
+  }
+
+  @Override
+  public void start() {
+    AsyncAppender asyncAppender = systemLog.createAsyncAppender(logName, layout);
+    Logger logger = LogManager.getLogger(logName);
+    logger.removeAppender(logName);
+    logger.addAppender(asyncAppender);
+    logger.setAdditivity(false);
+  }
+
+  @Override
+  public void stop() {
+    // stop is called when plugin is unloaded or when the server shutdown.
+    // Only clean up when the server is shutting down to prevent issue when a
+    // plugin is reloaded. The issue is that gerrit load the new plugin and then
+    // unload the old one so because loggers are static, the unload of the old
+    // plugin would remove the appenders just created by the new plugin.
+    if (serverInfo.getState() == ServerInformation.State.SHUTDOWN) {
+      LogManager.getLogger(logName).removeAllAppenders();
+    }
+  }
+}

java/com/google/gerrit/server/util/PluginRequestContext.java

@@ -0,0 +1,45 @@
+// Copyright (C) 2013 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.PluginUser;
+import com.google.inject.Provider;
+import com.google.inject.ProvisionException;
+
+/** RequestContext active while plugins load or unload. */
+public class PluginRequestContext implements RequestContext {
+  private final PluginUser user;
+
+  public PluginRequestContext(PluginUser user) {
+    this.user = user;
+  }
+
+  @Override
+  public CurrentUser getUser() {
+    return user;
+  }
+
+  @Override
+  public Provider<ReviewDb> getReviewDbProvider() {
+    return new Provider<ReviewDb>() {
+      @Override
+      public ReviewDb get() {
+        throw new ProvisionException("Automatic ReviewDb only available in request scope");
+      }
+    };
+  }
+}

java/com/google/gerrit/server/util/RegexListSearcher.java

@@ -0,0 +1,103 @@
+// Copyright (C) 2014 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import com.google.common.base.Function;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Lists;
+import com.google.common.primitives.Chars;
+import dk.brics.automaton.Automaton;
+import dk.brics.automaton.RegExp;
+import dk.brics.automaton.RunAutomaton;
+import java.util.Collections;
+import java.util.List;
+
+/** Helper to search sorted lists for elements matching a regex. */
+public abstract class RegexListSearcher<T> implements Function<T, String> {
+  public static RegexListSearcher<String> ofStrings(String re) {
+    return new RegexListSearcher<String>(re) {
+      @Override
+      public String apply(String in) {
+        return in;
+      }
+    };
+  }
+
+  private final RunAutomaton pattern;
+
+  private final String prefixBegin;
+  private final String prefixEnd;
+  private final int prefixLen;
+  private final boolean prefixOnly;
+
+  public RegexListSearcher(String re) {
+    if (re.startsWith("^")) {
+      re = re.substring(1);
+    }
+
+    if (re.endsWith("$") && !re.endsWith("\\$")) {
+      re = re.substring(0, re.length() - 1);
+    }
+
+    Automaton automaton = new RegExp(re).toAutomaton();
+    prefixBegin = automaton.getCommonPrefix();
+    prefixLen = prefixBegin.length();
+
+    if (0 < prefixLen) {
+      char max = Chars.checkedCast(prefixBegin.charAt(prefixLen - 1) + 1);
+      prefixEnd = prefixBegin.substring(0, prefixLen - 1) + max;
+      prefixOnly = re.equals(prefixBegin + ".*");
+    } else {
+      prefixEnd = "";
+      prefixOnly = false;
+    }
+
+    pattern = prefixOnly ? null : new RunAutomaton(automaton);
+  }
+
+  public Iterable<T> search(List<T> list) {
+    checkNotNull(list);
+    int begin;
+    int end;
+
+    if (0 < prefixLen) {
+      // Assumes many consecutive elements may have the same prefix, so the cost
+      // of two binary searches is less than iterating to find the endpoints.
+      begin = find(list, prefixBegin);
+      end = find(list, prefixEnd);
+    } else {
+      begin = 0;
+      end = list.size();
+    }
+
+    if (prefixOnly) {
+      return begin < end ? list.subList(begin, end) : ImmutableList.<T>of();
+    }
+
+    return Iterables.filter(list.subList(begin, end), x -> pattern.run(apply(x)));
+  }
+
+  public boolean hasMatch(List<T> list) {
+    return !Iterables.isEmpty(search(list));
+  }
+
+  private int find(List<T> list, String p) {
+    int r = Collections.binarySearch(Lists.transform(list, this), p);
+    return r < 0 ? -(r + 1) : r;
+  }
+}

java/com/google/gerrit/server/util/RequestContext.java

@@ -0,0 +1,29 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.CurrentUser;
+import com.google.inject.Provider;
+
+/**
+ * The RequestContext is an interface exposing the fields that are needed by the GerritGlobalModule
+ * scope.
+ */
+public interface RequestContext {
+  CurrentUser getUser();
+
+  Provider<ReviewDb> getReviewDbProvider();
+}

java/com/google/gerrit/server/util/RequestId.java

@@ -0,0 +1,70 @@
+// Copyright (C) 2016 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.common.hash.Hasher;
+import com.google.common.hash.Hashing;
+import com.google.gerrit.common.TimeUtil;
+import com.google.gerrit.reviewdb.client.Change;
+import com.google.gerrit.reviewdb.client.Project;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+/** Unique identifier for an end-user request, used in logs and similar. */
+public class RequestId {
+  private static final String MACHINE_ID;
+
+  static {
+    String id;
+    try {
+      id = InetAddress.getLocalHost().getHostAddress();
+    } catch (UnknownHostException e) {
+      id = "unknown";
+    }
+    MACHINE_ID = id;
+  }
+
+  public static RequestId forChange(Change c) {
+    return new RequestId(c.getId().toString());
+  }
+
+  public static RequestId forProject(Project.NameKey p) {
+    return new RequestId(p.toString());
+  }
+
+  private final String str;
+
+  private RequestId(String resourceId) {
+    Hasher h = Hashing.murmur3_128().newHasher();
+    h.putLong(Thread.currentThread().getId()).putUnencodedChars(MACHINE_ID);
+    str =
+        "["
+            + resourceId
+            + "-"
+            + TimeUtil.nowTs().getTime()
+            + "-"
+            + h.hash().toString().substring(0, 8)
+            + "]";
+  }
+
+  @Override
+  public String toString() {
+    return str;
+  }
+
+  public String toStringForStorage() {
+    return str.substring(1, str.length() - 1);
+  }
+}

java/com/google/gerrit/server/util/RequestScopePropagator.java

@@ -0,0 +1,218 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import com.google.common.base.Throwables;
+import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.RequestCleanup;
+import com.google.gerrit.server.config.RequestScopedReviewDbProvider;
+import com.google.gerrit.server.git.ProjectRunnable;
+import com.google.inject.Key;
+import com.google.inject.Provider;
+import com.google.inject.Scope;
+import com.google.inject.servlet.ServletScopes;
+import java.util.concurrent.Callable;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+
+/**
+ * Base class for propagating request-scoped data between threads.
+ *
+ * <p>Request scopes are typically linked to a {@link ThreadLocal}, which is only available to the
+ * current thread. In order to allow background work involving RequestScoped data, the ThreadLocal
+ * data must be copied from the request thread to the new background thread.
+ *
+ * <p>Every type of RequestScope must provide an implementation of RequestScopePropagator. See
+ * {@link #wrap(Callable)} for details on the implementation, usage, and restrictions.
+ *
+ * @see ThreadLocalRequestScopePropagator
+ */
+public abstract class RequestScopePropagator {
+
+  private final Scope scope;
+  private final ThreadLocalRequestContext local;
+  private final Provider<RequestScopedReviewDbProvider> dbProviderProvider;
+
+  protected RequestScopePropagator(
+      Scope scope,
+      ThreadLocalRequestContext local,
+      Provider<RequestScopedReviewDbProvider> dbProviderProvider) {
+    this.scope = scope;
+    this.local = local;
+    this.dbProviderProvider = dbProviderProvider;
+  }
+
+  /**
+   * Ensures that the current request state is available when the passed in Callable is invoked.
+   *
+   * <p>If needed wraps the passed in Callable in a new {@link Callable} that propagates the current
+   * request state when the returned Callable is invoked. The method must be called in a request
+   * scope and the returned Callable may only be invoked in a thread that is not already in a
+   * request scope or is in the same request scope. The returned Callable will inherit toString()
+   * from the passed in Callable. A {@link ScheduledThreadPoolExecutor} does not accept a Callable,
+   * so there is no ProjectCallable implementation. Implementations of this method must be
+   * consistent with Guice's {@link ServletScopes#continueRequest(Callable, java.util.Map)}.
+   *
+   * <p>There are some limitations:
+   *
+   * <ul>
+   *   <li>Derived objects (i.e. anything marked created in a request scope) will not be
+   *       transported.
+   *   <li>State changes to the request scoped context after this method is called will not be seen
+   *       in the continued thread.
+   * </ul>
+   *
+   * @param callable the Callable to wrap.
+   * @return a new Callable which will execute in the current request scope.
+   */
+  @SuppressWarnings("javadoc") // See GuiceRequestScopePropagator#wrapImpl
+  public final <T> Callable<T> wrap(Callable<T> callable) {
+    final RequestContext callerContext = checkNotNull(local.getContext());
+    final Callable<T> wrapped = wrapImpl(context(callerContext, cleanup(callable)));
+    return new Callable<T>() {
+      @Override
+      public T call() throws Exception {
+        if (callerContext == local.getContext()) {
+          return callable.call();
+        }
+        return wrapped.call();
+      }
+
+      @Override
+      public String toString() {
+        return callable.toString();
+      }
+    };
+  }
+
+  /**
+   * Wraps runnable in a new {@link Runnable} that propagates the current request state when the
+   * runnable is invoked. The method must be called in a request scope and the returned Runnable may
+   * only be invoked in a thread that is not already in a request scope. The returned Runnable will
+   * inherit toString() from the passed in Runnable. Furthermore, if the passed runnable is of type
+   * {@link ProjectRunnable}, the returned runnable will be of the same type with the methods
+   * delegated.
+   *
+   * <p>See {@link #wrap(Callable)} for details on implementation and usage.
+   *
+   * @param runnable the Runnable to wrap.
+   * @return a new Runnable which will execute in the current request scope.
+   */
+  public final Runnable wrap(Runnable runnable) {
+    final Callable<Object> wrapped = wrap(Executors.callable(runnable));
+
+    if (runnable instanceof ProjectRunnable) {
+      return new ProjectRunnable() {
+        @Override
+        public void run() {
+          try {
+            wrapped.call();
+          } catch (Exception e) {
+            Throwables.throwIfUnchecked(e);
+            throw new RuntimeException(e); // Not possible.
+          }
+        }
+
+        @Override
+        public Project.NameKey getProjectNameKey() {
+          return ((ProjectRunnable) runnable).getProjectNameKey();
+        }
+
+        @Override
+        public String getRemoteName() {
+          return ((ProjectRunnable) runnable).getRemoteName();
+        }
+
+        @Override
+        public boolean hasCustomizedPrint() {
+          return ((ProjectRunnable) runnable).hasCustomizedPrint();
+        }
+
+        @Override
+        public String toString() {
+          return runnable.toString();
+        }
+      };
+    }
+    return new Runnable() {
+      @Override
+      public void run() {
+        try {
+          wrapped.call();
+        } catch (RuntimeException e) {
+          throw e;
+        } catch (Exception e) {
+          throw new RuntimeException(e); // Not possible.
+        }
+      }
+
+      @Override
+      public String toString() {
+        return runnable.toString();
+      }
+    };
+  }
+
+  /** @see #wrap(Callable) */
+  protected abstract <T> Callable<T> wrapImpl(Callable<T> callable);
+
+  protected <T> Callable<T> context(RequestContext context, Callable<T> callable) {
+    return () -> {
+      RequestContext old =
+          local.setContext(
+              new RequestContext() {
+                @Override
+                public CurrentUser getUser() {
+                  return context.getUser();
+                }
+
+                @Override
+                public Provider<ReviewDb> getReviewDbProvider() {
+                  return dbProviderProvider.get();
+                }
+              });
+      try {
+        return callable.call();
+      } finally {
+        local.setContext(old);
+      }
+    };
+  }
+
+  protected <T> Callable<T> cleanup(Callable<T> callable) {
+    return () -> {
+      RequestCleanup cleanup =
+          scope
+              .scope(
+                  Key.get(RequestCleanup.class),
+                  new Provider<RequestCleanup>() {
+                    @Override
+                    public RequestCleanup get() {
+                      return new RequestCleanup();
+                    }
+                  })
+              .get();
+      try {
+        return callable.call();
+      } finally {
+        cleanup.run();
+      }
+    };
+  }
+}

java/com/google/gerrit/server/util/ServerRequestContext.java

@@ -0,0 +1,47 @@
+// Copyright (C) 2013 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.InternalUser;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.ProvisionException;
+
+/** RequestContext with an InternalUser making the internals visible. */
+public class ServerRequestContext implements RequestContext {
+  private final InternalUser user;
+
+  @Inject
+  ServerRequestContext(InternalUser.Factory userFactory) {
+    this.user = userFactory.create();
+  }
+
+  @Override
+  public CurrentUser getUser() {
+    return user;
+  }
+
+  @Override
+  public Provider<ReviewDb> getReviewDbProvider() {
+    return new Provider<ReviewDb>() {
+      @Override
+      public ReviewDb get() {
+        throw new ProvisionException("Automatic ReviewDb only available in request scope");
+      }
+    };
+  }
+}

java/com/google/gerrit/server/util/SocketUtil.java

@@ -0,0 +1,126 @@
+// Copyright (C) 2009 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import java.net.Inet6Address;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+import java.net.UnknownHostException;
+
+public final class SocketUtil {
+  /** True if this InetAddress is a raw IPv6 in dotted quad notation. */
+  public static boolean isIPv6(InetAddress ip) {
+    return ip instanceof Inet6Address && ip.getHostName().equals(ip.getHostAddress());
+  }
+
+  /** Get the name or IP address, or {@code *} if this address is a wildcard IP. */
+  public static String hostname(InetSocketAddress addr) {
+    if (addr.getAddress() != null) {
+      if (addr.getAddress().isAnyLocalAddress()) {
+        return "*";
+      }
+      return addr.getAddress().getHostName();
+    }
+    return addr.getHostName();
+  }
+
+  /** Format an address string into {@code host:port} or {@code *:port} syntax. */
+  public static String format(SocketAddress s, int defaultPort) {
+    if (s instanceof InetSocketAddress) {
+      final InetSocketAddress addr = (InetSocketAddress) s;
+      if (addr.getPort() == defaultPort) {
+        return safeHostname(hostname(addr));
+      }
+      return format(hostname(addr), addr.getPort());
+    }
+    return s.toString();
+  }
+
+  /** Format an address string into {@code host:port} or {@code *:port} syntax. */
+  public static String format(String hostname, int port) {
+    return safeHostname(hostname) + ":" + port;
+  }
+
+  private static String safeHostname(String hostname) {
+    if (0 <= hostname.indexOf(':')) {
+      hostname = "[" + hostname + "]";
+    }
+    return hostname;
+  }
+
+  /** Parse an address string such as {@code host:port} or {@code *:port}. */
+  public static InetSocketAddress parse(String desc, int defaultPort) {
+    String hostStr;
+    String portStr;
+
+    if (desc.startsWith("[")) {
+      // IPv6, as a raw IP address.
+      //
+      final int hostEnd = desc.indexOf(']');
+      if (hostEnd < 0) {
+        throw new IllegalArgumentException("invalid IPv6: " + desc);
+      }
+
+      hostStr = desc.substring(1, hostEnd);
+      portStr = desc.substring(hostEnd + 1);
+    } else {
+      // IPv4, or a host name.
+      //
+      final int hostEnd = desc.indexOf(':');
+      hostStr = 0 <= hostEnd ? desc.substring(0, hostEnd) : desc;
+      portStr = 0 <= hostEnd ? desc.substring(hostEnd) : "";
+    }
+
+    if ("".equals(hostStr)) {
+      hostStr = "*";
+    }
+    if (portStr.startsWith(":")) {
+      portStr = portStr.substring(1);
+    }
+
+    final int port;
+    if (portStr.length() > 0) {
+      try {
+        port = Integer.parseInt(portStr);
+      } catch (NumberFormatException e) {
+        throw new IllegalArgumentException("invalid port: " + desc);
+      }
+    } else {
+      port = defaultPort;
+    }
+
+    if ("*".equals(hostStr)) {
+      return new InetSocketAddress(port);
+    }
+    return InetSocketAddress.createUnresolved(hostStr, port);
+  }
+
+  /** Parse and resolve an address string, looking up the IP address. */
+  public static InetSocketAddress resolve(String desc, int defaultPort) {
+    final InetSocketAddress addr = parse(desc, defaultPort);
+    if (addr.getAddress() != null && addr.getAddress().isAnyLocalAddress()) {
+      return addr;
+    }
+    try {
+      final InetAddress host = InetAddress.getByName(addr.getHostName());
+      return new InetSocketAddress(host, addr.getPort());
+    } catch (UnknownHostException e) {
+      throw new IllegalArgumentException("unknown host: " + desc, e);
+    }
+  }
+
+  private SocketUtil() {}
+}

java/com/google/gerrit/server/util/SubmoduleSectionParser.java

@@ -0,0 +1,145 @@
+// Copyright (C) 2011 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.reviewdb.client.Branch;
+import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.reviewdb.client.SubmoduleSubscription;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.HashSet;
+import java.util.Set;
+import org.eclipse.jgit.lib.Config;
+import org.eclipse.jgit.lib.Constants;
+
+/**
+ * It parses from a configuration file submodule sections.
+ *
+ * <p>Example of submodule sections:
+ *
+ * <pre>
+ * [submodule "project-a"]
+ *     url = http://localhost/a
+ *     path = a
+ *     branch = .
+ *
+ * [submodule "project-b"]
+ *     url = http://localhost/b
+ *     path = b
+ *     branch = refs/heads/test
+ * </pre>
+ */
+public class SubmoduleSectionParser {
+
+  private final Config bbc;
+  private final String canonicalWebUrl;
+  private final Branch.NameKey superProjectBranch;
+
+  public SubmoduleSectionParser(
+      Config bbc, String canonicalWebUrl, Branch.NameKey superProjectBranch) {
+    this.bbc = bbc;
+    this.canonicalWebUrl = canonicalWebUrl;
+    this.superProjectBranch = superProjectBranch;
+  }
+
+  public Set<SubmoduleSubscription> parseAllSections() {
+    Set<SubmoduleSubscription> parsedSubscriptions = new HashSet<>();
+    for (String id : bbc.getSubsections("submodule")) {
+      final SubmoduleSubscription subscription = parse(id);
+      if (subscription != null) {
+        parsedSubscriptions.add(subscription);
+      }
+    }
+    return parsedSubscriptions;
+  }
+
+  private SubmoduleSubscription parse(String id) {
+    final String url = bbc.getString("submodule", id, "url");
+    final String path = bbc.getString("submodule", id, "path");
+    String branch = bbc.getString("submodule", id, "branch");
+
+    try {
+      if (url != null
+          && url.length() > 0
+          && path != null
+          && path.length() > 0
+          && branch != null
+          && branch.length() > 0) {
+        // All required fields filled.
+        String project;
+
+        if (branch.equals(".")) {
+          branch = superProjectBranch.get();
+        }
+
+        // relative URL
+        if (url.startsWith("../")) {
+          // prefix with a slash for easier relative path walks
+          project = '/' + superProjectBranch.getParentKey().get();
+          String hostPart = url;
+          while (hostPart.startsWith("../")) {
+            int lastSlash = project.lastIndexOf('/');
+            if (lastSlash < 0) {
+              // too many levels up, ignore for now
+              return null;
+            }
+            project = project.substring(0, lastSlash);
+            hostPart = hostPart.substring(3);
+          }
+          project = project + "/" + hostPart;
+
+          // remove leading '/'
+          project = project.substring(1);
+        } else {
+          // It is actually an URI. It could be ssh://localhost/project-a.
+          URI targetServerURI = new URI(url);
+          URI thisServerURI = new URI(canonicalWebUrl);
+          String thisHost = thisServerURI.getHost();
+          String targetHost = targetServerURI.getHost();
+          if (thisHost == null || targetHost == null || !targetHost.equalsIgnoreCase(thisHost)) {
+            return null;
+          }
+          String p1 = targetServerURI.getPath();
+          String p2 = thisServerURI.getPath();
+          if (!p1.startsWith(p2)) {
+            // When we are running the server at
+            // http://server/my-gerrit/ but the subscription is for
+            // http://server/other-teams-gerrit/
+            return null;
+          }
+          // skip common part
+          project = p1.substring(p2.length());
+        }
+
+        while (project.startsWith("/")) {
+          project = project.substring(1);
+        }
+
+        if (project.endsWith(Constants.DOT_GIT_EXT)) {
+          project =
+              project.substring(
+                  0, //
+                  project.length() - Constants.DOT_GIT_EXT.length());
+        }
+        Project.NameKey projectKey = new Project.NameKey(project);
+        return new SubmoduleSubscription(
+            superProjectBranch, new Branch.NameKey(projectKey, branch), path);
+      }
+    } catch (URISyntaxException e) {
+      // Error in url syntax (in fact it is uri syntax)
+    }
+    return null;
+  }
+}

java/com/google/gerrit/server/util/SystemLog.java

@@ -0,0 +1,130 @@
+// Copyright (C) 2014 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import com.google.common.base.Strings;
+import com.google.gerrit.common.Die;
+import com.google.gerrit.server.config.GerritServerConfig;
+import com.google.gerrit.server.config.SitePaths;
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import java.nio.file.Path;
+import org.apache.log4j.Appender;
+import org.apache.log4j.AsyncAppender;
+import org.apache.log4j.DailyRollingFileAppender;
+import org.apache.log4j.Layout;
+import org.apache.log4j.LogManager;
+import org.apache.log4j.Logger;
+import org.apache.log4j.helpers.OnlyOnceErrorHandler;
+import org.apache.log4j.spi.ErrorHandler;
+import org.apache.log4j.spi.LoggingEvent;
+import org.eclipse.jgit.lib.Config;
+import org.slf4j.LoggerFactory;
+
+@Singleton
+public class SystemLog {
+  private static final org.slf4j.Logger log = LoggerFactory.getLogger(SystemLog.class);
+
+  public static final String LOG4J_CONFIGURATION = "log4j.configuration";
+
+  private final SitePaths site;
+  private final Config config;
+
+  @Inject
+  public SystemLog(SitePaths site, @GerritServerConfig Config config) {
+    this.site = site;
+    this.config = config;
+  }
+
+  public static boolean shouldConfigure() {
+    return Strings.isNullOrEmpty(System.getProperty(LOG4J_CONFIGURATION));
+  }
+
+  public static Appender createAppender(Path logdir, String name, Layout layout) {
+    final DailyRollingFileAppender dst = new DailyRollingFileAppender();
+    dst.setName(name);
+    dst.setLayout(layout);
+    dst.setEncoding(UTF_8.name());
+    dst.setFile(resolve(logdir).resolve(name).toString());
+    dst.setImmediateFlush(true);
+    dst.setAppend(true);
+    dst.setErrorHandler(new DieErrorHandler());
+    dst.activateOptions();
+    dst.setErrorHandler(new OnlyOnceErrorHandler());
+    return dst;
+  }
+
+  public AsyncAppender createAsyncAppender(String name, Layout layout) {
+    AsyncAppender async = new AsyncAppender();
+    async.setName(name);
+    async.setBlocking(true);
+    async.setBufferSize(config.getInt("core", "asyncLoggingBufferSize", 64));
+    async.setLocationInfo(false);
+
+    if (shouldConfigure()) {
+      async.addAppender(createAppender(site.logs_dir, name, layout));
+    } else {
+      Appender appender = LogManager.getLogger(name).getAppender(name);
+      if (appender != null) {
+        async.addAppender(appender);
+      } else {
+        log.warn(
+            "No appender with the name: " + name + " was found. " + name + " logging is disabled");
+      }
+    }
+    async.activateOptions();
+    return async;
+  }
+
+  private static Path resolve(Path p) {
+    try {
+      return p.toRealPath().normalize();
+    } catch (IOException e) {
+      return p.toAbsolutePath().normalize();
+    }
+  }
+
+  private static final class DieErrorHandler implements ErrorHandler {
+    @Override
+    public void error(String message, Exception e, int errorCode, LoggingEvent event) {
+      error(e != null ? e.getMessage() : message);
+    }
+
+    @Override
+    public void error(String message, Exception e, int errorCode) {
+      error(e != null ? e.getMessage() : message);
+    }
+
+    @Override
+    public void error(String message) {
+      throw new Die("Cannot open log file: " + message);
+    }
+
+    @Override
+    public void activateOptions() {}
+
+    @Override
+    public void setAppender(Appender appender) {}
+
+    @Override
+    public void setBackupAppender(Appender appender) {}
+
+    @Override
+    public void setLogger(Logger logger) {}
+  }
+}

java/com/google/gerrit/server/util/ThreadLocalRequestContext.java

@@ -0,0 +1,89 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.common.base.MoreObjects;
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.common.errors.NotSignedInException;
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.IdentifiedUser;
+import com.google.inject.AbstractModule;
+import com.google.inject.Inject;
+import com.google.inject.Module;
+import com.google.inject.Provides;
+import com.google.inject.ProvisionException;
+import com.google.inject.name.Named;
+import com.google.inject.name.Names;
+
+/**
+ * ThreadLocalRequestContext manages the current RequestContext using a ThreadLocal. When the
+ * context is set, the fields exposed by the context are considered in scope. Otherwise, the
+ * FallbackRequestContext is used.
+ */
+public class ThreadLocalRequestContext {
+  private static final String FALLBACK = "FALLBACK";
+
+  public static Module module() {
+    return new AbstractModule() {
+      @Override
+      protected void configure() {
+        bind(ThreadLocalRequestContext.class);
+        bind(RequestContext.class)
+            .annotatedWith(Names.named(FALLBACK))
+            .to(FallbackRequestContext.class);
+      }
+
+      @Provides
+      RequestContext provideRequestContext(@Named(FALLBACK) RequestContext fallback) {
+        return MoreObjects.firstNonNull(local.get(), fallback);
+      }
+
+      @Provides
+      CurrentUser provideCurrentUser(RequestContext ctx) {
+        return ctx.getUser();
+      }
+
+      @Provides
+      IdentifiedUser provideCurrentUser(CurrentUser user) {
+        if (user.isIdentifiedUser()) {
+          return user.asIdentifiedUser();
+        }
+        throw new ProvisionException(NotSignedInException.MESSAGE, new NotSignedInException());
+      }
+
+      @Provides
+      ReviewDb provideReviewDb(RequestContext ctx) {
+        return ctx.getReviewDbProvider().get();
+      }
+    };
+  }
+
+  private static final ThreadLocal<RequestContext> local = new ThreadLocal<>();
+
+  @Inject
+  ThreadLocalRequestContext() {}
+
+  public RequestContext setContext(@Nullable RequestContext ctx) {
+    RequestContext old = getContext();
+    local.set(ctx);
+    return old;
+  }
+
+  @Nullable
+  public RequestContext getContext() {
+    return local.get();
+  }
+}

java/com/google/gerrit/server/util/ThreadLocalRequestScopePropagator.java

@@ -0,0 +1,82 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import com.google.gerrit.server.config.RequestScopedReviewDbProvider;
+import com.google.inject.OutOfScopeException;
+import com.google.inject.Provider;
+import com.google.inject.Scope;
+import java.util.concurrent.Callable;
+
+/**
+ * {@link RequestScopePropagator} implementation for request scopes based on a {@link ThreadLocal}
+ * context.
+ *
+ * @param <C> "context" type stored in the {@link ThreadLocal}.
+ */
+public abstract class ThreadLocalRequestScopePropagator<C> extends RequestScopePropagator {
+
+  private final ThreadLocal<C> threadLocal;
+
+  protected ThreadLocalRequestScopePropagator(
+      Scope scope,
+      ThreadLocal<C> threadLocal,
+      ThreadLocalRequestContext local,
+      Provider<RequestScopedReviewDbProvider> dbProviderProvider) {
+    super(scope, local, dbProviderProvider);
+    this.threadLocal = threadLocal;
+  }
+
+  /** @see RequestScopePropagator#wrap(Callable) */
+  @Override
+  protected final <T> Callable<T> wrapImpl(Callable<T> callable) {
+    C ctx = continuingContext(requireContext());
+    return () -> {
+      C old = threadLocal.get();
+      threadLocal.set(ctx);
+      try {
+        return callable.call();
+      } finally {
+        if (old != null) {
+          threadLocal.set(old);
+        } else {
+          threadLocal.remove();
+        }
+      }
+    };
+  }
+
+  private C requireContext() {
+    C context = threadLocal.get();
+    if (context == null) {
+      throw new OutOfScopeException("Cannot access scoped object");
+    }
+    return context;
+  }
+
+  /**
+   * Returns a new context object based on the passed in context that has no request scoped objects
+   * initialized.
+   *
+   * <p>Note that some code paths expect request-scoped objects like {@code CurrentUser} to be
+   * constructible starting from just the context object returned by this method. For example, in
+   * the SSH scope, the context includes the {@code SshSession}, which is used by {@code
+   * SshCurrentUserProvider} to construct a new {@code CurrentUser} in the new thread.
+   *
+   * @param ctx the context to continue.
+   * @return a new context.
+   */
+  protected abstract C continuingContext(C ctx);
+}

java/com/google/gerrit/server/util/TreeFormatter.java

@@ -0,0 +1,94 @@
+// Copyright (C) 2011 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import java.io.PrintWriter;
+import java.util.SortedSet;
+
+public class TreeFormatter {
+
+  public interface TreeNode {
+    String getDisplayName();
+
+    boolean isVisible();
+
+    SortedSet<? extends TreeNode> getChildren();
+  }
+
+  public static final String NOT_VISIBLE_NODE = "(x)";
+
+  private static final String NODE_PREFIX = "|-- ";
+  private static final String LAST_NODE_PREFIX = "`-- ";
+  private static final String DEFAULT_TAB_SEPARATOR = "|";
+
+  private final PrintWriter stdout;
+  private String currentTabSeparator = " ";
+
+  public TreeFormatter(PrintWriter stdout) {
+    this.stdout = stdout;
+  }
+
+  public void printTree(SortedSet<? extends TreeNode> rootNodes) {
+    if (rootNodes.isEmpty()) {
+      return;
+    }
+    if (rootNodes.size() == 1) {
+      printTree(rootNodes.first());
+    } else {
+      currentTabSeparator = DEFAULT_TAB_SEPARATOR;
+      int i = 0;
+      final int size = rootNodes.size();
+      for (TreeNode rootNode : rootNodes) {
+        final boolean isLastRoot = ++i == size;
+        if (isLastRoot) {
+          currentTabSeparator = " ";
+        }
+        printTree(rootNode);
+      }
+    }
+  }
+
+  public void printTree(TreeNode rootNode) {
+    printTree(rootNode, 0, true);
+  }
+
+  private void printTree(TreeNode node, int level, boolean isLast) {
+    printNode(node, level, isLast);
+    final SortedSet<? extends TreeNode> childNodes = node.getChildren();
+    int i = 0;
+    final int size = childNodes.size();
+    for (TreeNode childNode : childNodes) {
+      final boolean isLastChild = ++i == size;
+      printTree(childNode, level + 1, isLastChild);
+    }
+  }
+
+  private void printIndention(int level) {
+    if (level > 0) {
+      stdout.print(String.format("%-" + 4 * level + "s", currentTabSeparator));
+    }
+  }
+
+  private void printNode(TreeNode node, int level, boolean isLast) {
+    printIndention(level);
+    stdout.print(isLast ? LAST_NODE_PREFIX : NODE_PREFIX);
+    if (node.isVisible()) {
+      stdout.print(node.getDisplayName());
+    } else {
+      stdout.print(NOT_VISIBLE_NODE);
+    }
+    stdout.print("\n");
+  }
+}