| /* |
| * Copyright (C) 2019, Google LLC. |
| * 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 com.google.gitiles; |
| |
| import java.io.IOException; |
| import java.util.Collection; |
| import org.eclipse.jgit.errors.IncorrectObjectTypeException; |
| import org.eclipse.jgit.errors.MissingObjectException; |
| import org.eclipse.jgit.lib.ObjectId; |
| import org.eclipse.jgit.lib.Ref; |
| import org.eclipse.jgit.lib.RefDatabase; |
| import org.eclipse.jgit.revwalk.RevCommit; |
| import org.eclipse.jgit.revwalk.RevSort; |
| import org.eclipse.jgit.revwalk.RevWalk; |
| |
| /** |
| * Checks for object visibility |
| * |
| * <p>Objects are visible if they are reachable from any of the references visible to the user. |
| */ |
| public class VisibilityChecker { |
| |
| private final boolean topoSort; |
| |
| /** |
| * @param topoSort whether to use a more thorough reachability check by sorting in topological |
| * order |
| */ |
| public VisibilityChecker(boolean topoSort) { |
| this.topoSort = topoSort; |
| } |
| |
| /** |
| * Check if any of the refs in {@code refDb} points to the object {@code id}. |
| * |
| * @param refDb a reference database |
| * @param id object we are looking for |
| * @return true if the any of the references in the db points directly to the id |
| * @throws IOException the reference space cannot be accessed |
| */ |
| protected boolean isTipOfBranch(RefDatabase refDb, ObjectId id) throws IOException { |
| // If any reference directly points at the requested object, permit display. Common for displays |
| // of pending patch sets in Gerrit Code Review, or bookmarks to the commit a tag points at. |
| for (Ref ref : refDb.getRefs()) { |
| ref = refDb.peel(ref); |
| if (id.equals(ref.getObjectId()) || id.equals(ref.getPeeledObjectId())) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Check if {@code commit} is reachable starting from {@code starters}. |
| * |
| * @param description Description of the ids (e.g. "heads"). Mainly for tracing. |
| * @param walk The walk to use for the reachability check |
| * @param commit The starting commit. It *MUST* come from the walk in use |
| * @param starters visible commits. Anything reachable from these commits is visible. Missing ids |
| * or ids pointing to wrong kind of objects are ignored. |
| * @return true if we can get to {@code commit} from the {@code starters} |
| * @throws IOException a pack file or loose object could not be read |
| */ |
| protected boolean isReachableFrom( |
| String description, RevWalk walk, RevCommit commit, Collection<ObjectId> starters) |
| throws IOException { |
| if (starters.isEmpty()) { |
| return false; |
| } |
| |
| walk.reset(); |
| if (topoSort) { |
| walk.sort(RevSort.TOPO); |
| } |
| |
| walk.markStart(commit); |
| for (ObjectId id : starters) { |
| markUninteresting(walk, id); |
| } |
| // If the commit is reachable from any given tip, it will appear to be |
| // uninteresting to the RevWalk and no output will be produced. |
| return walk.next() == null; |
| } |
| |
| private static void markUninteresting(RevWalk walk, ObjectId id) throws IOException { |
| if (id == null) { |
| return; |
| } |
| try { |
| walk.markUninteresting(walk.parseCommit(id)); |
| } catch (IncorrectObjectTypeException | MissingObjectException e) { |
| // Do nothing, doesn't affect reachability. |
| } |
| } |
| } |