| /* |
| * 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 org.eclipse.jgit.revwalk; |
| |
| import static java.util.Objects.requireNonNull; |
| |
| import java.io.IOException; |
| |
| import org.eclipse.jgit.errors.IncorrectObjectTypeException; |
| import org.eclipse.jgit.errors.MissingObjectException; |
| import org.eclipse.jgit.internal.revwalk.AddToBitmapFilter; |
| import org.eclipse.jgit.lib.BitmapIndex; |
| import org.eclipse.jgit.lib.BitmapIndex.Bitmap; |
| import org.eclipse.jgit.lib.BitmapIndex.BitmapBuilder; |
| import org.eclipse.jgit.lib.ProgressMonitor; |
| |
| /** |
| * Calculate the bitmap indicating what other commits are reachable from certain |
| * commit. |
| * <p> |
| * This bitmap refers only to commits. For a bitmap with ALL objects reachable |
| * from certain object, see {@code BitmapWalker}. |
| */ |
| class BitmapCalculator { |
| |
| private final RevWalk walk; |
| private final BitmapIndex bitmapIndex; |
| |
| BitmapCalculator(RevWalk walk) throws IOException { |
| this.walk = walk; |
| this.bitmapIndex = requireNonNull( |
| walk.getObjectReader().getBitmapIndex()); |
| } |
| |
| /** |
| * Get the reachability bitmap from certain commit to other commits. |
| * <p> |
| * This will return a precalculated bitmap if available or walk building one |
| * until finding a precalculated bitmap (and returning the union). |
| * <p> |
| * Beware that the returned bitmap it is guaranteed to include ONLY the |
| * commits reachable from the initial commit. It COULD include other objects |
| * (because precalculated bitmaps have them) but caller shouldn't count on |
| * that. See {@link BitmapWalker} for a full reachability bitmap. |
| * |
| * @param start |
| * the commit. Use {@code walk.parseCommit(objectId)} to get this |
| * object from the id. |
| * @param pm |
| * progress monitor. Updated by one per commit browsed in the |
| * graph |
| * @return the bitmap of reachable commits (and maybe some extra objects) |
| * for the commit |
| * @throws MissingObjectException |
| * the supplied id doesn't exist |
| * @throws IncorrectObjectTypeException |
| * the supplied id doesn't refer to a commit or a tag |
| * @throws IOException |
| * if the walk cannot open a packfile or loose object |
| */ |
| BitmapBuilder getBitmap(RevCommit start, ProgressMonitor pm) |
| throws MissingObjectException, |
| IncorrectObjectTypeException, IOException { |
| Bitmap precalculatedBitmap = bitmapIndex.getBitmap(start); |
| if (precalculatedBitmap != null) { |
| return asBitmapBuilder(precalculatedBitmap); |
| } |
| |
| walk.reset(); |
| walk.sort(RevSort.TOPO); |
| walk.markStart(start); |
| // Unbounded walk. If the repo has bitmaps, it should bump into one at |
| // some point. |
| |
| BitmapBuilder bitmapResult = bitmapIndex.newBitmapBuilder(); |
| walk.setRevFilter(new AddToBitmapFilter(bitmapResult)); |
| while (walk.next() != null) { |
| // Iterate through all of the commits. The BitmapRevFilter does |
| // the work. |
| // |
| // filter.include returns true for commits that do not have |
| // a bitmap in bitmapIndex and are not reachable from a |
| // bitmap in bitmapIndex encountered earlier in the walk. |
| // Thus the number of commits returned by next() measures how |
| // much history was traversed without being able to make use |
| // of bitmaps. |
| pm.update(1); |
| } |
| |
| return bitmapResult; |
| } |
| |
| private BitmapBuilder asBitmapBuilder(Bitmap bitmap) { |
| return bitmapIndex.newBitmapBuilder().or(bitmap); |
| } |
| } |