1 /* 2 * Copyright (C) 2017, Google Inc. 3 * and other copyright owners as documented in the project's IP log. 4 * 5 * This program and the accompanying materials are made available 6 * under the terms of the Eclipse Distribution License v1.0 which 7 * accompanies this distribution, is reproduced below, and is 8 * available at http://www.eclipse.org/org/documents/edl-v10.php 9 * 10 * All rights reserved. 11 * 12 * Redistribution and use in source and binary forms, with or 13 * without modification, are permitted provided that the following 14 * conditions are met: 15 * 16 * - Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials provided 22 * with the distribution. 23 * 24 * - Neither the name of the Eclipse Foundation, Inc. nor the 25 * names of its contributors may be used to endorse or promote 26 * products derived from this software without specific prior 27 * written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 30 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 31 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 33 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 34 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 35 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 37 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 38 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 41 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 42 */ 43 44 package org.eclipse.jgit.internal.revwalk; 45 46 import org.eclipse.jgit.lib.BitmapIndex.Bitmap; 47 import org.eclipse.jgit.lib.BitmapIndex.BitmapBuilder; 48 import org.eclipse.jgit.lib.Constants; 49 import org.eclipse.jgit.revwalk.filter.RevFilter; 50 import org.eclipse.jgit.revwalk.RevWalk; 51 import org.eclipse.jgit.revwalk.RevCommit; 52 import org.eclipse.jgit.revwalk.RevFlag; 53 54 /** 55 * A RevFilter that adds the visited commits to {@code bitmap} as a side 56 * effect. 57 * <p> 58 * When the walk hits a commit that is part of {@code bitmap}'s 59 * BitmapIndex, that entire bitmap is ORed into {@code bitmap} and the 60 * commit and its parents are marked as SEEN so that the walk does not 61 * have to visit its ancestors. This ensures the walk is very short if 62 * there is good bitmap coverage. 63 * <p> 64 * Commits named in {@code seen} are considered already seen. If one is 65 * encountered, that commit and its parents will be marked with the SEEN 66 * flag to prevent the walk from visiting its ancestors. 67 */ 68 public class AddUnseenToBitmapFilter extends RevFilter { 69 private final BitmapBuilder seen; 70 private final BitmapBuilder bitmap; 71 72 /** 73 * Create a filter that adds visited commits to the given bitmap, but does not walk 74 * through the objects in {@code seen}. 75 * 76 * @param seen objects that are already seen 77 * @param bitmap bitmap to write visited commits to 78 */ 79 public AddUnseenToBitmapFilter(BitmapBuilder seen, BitmapBuilder bitmap) { 80 this.seen = seen; 81 this.bitmap = bitmap; 82 } 83 84 /** {@inheritDoc} */ 85 @Override 86 public final boolean include(RevWalk walker, RevCommit cmit) { 87 Bitmap visitedBitmap; 88 89 if (seen.contains(cmit) || bitmap.contains(cmit)) { 90 // already seen or included 91 } else if ((visitedBitmap = bitmap.getBitmapIndex() 92 .getBitmap(cmit)) != null) { 93 bitmap.or(visitedBitmap); 94 } else { 95 bitmap.addObject(cmit, Constants.OBJ_COMMIT); 96 return true; 97 } 98 99 for (RevCommit p : cmit.getParents()) { 100 p.add(RevFlag.SEEN); 101 } 102 return false; 103 } 104 105 /** {@inheritDoc} */ 106 @Override 107 public final RevFilter clone() { 108 throw new UnsupportedOperationException(); 109 } 110 111 /** {@inheritDoc} */ 112 @Override 113 public final boolean requiresCommitBody() { 114 return false; 115 } 116 }