| /* |
| * Copyright (C) 2012, Google Inc. |
| * 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.internal.storage.pack; |
| |
| import java.io.IOException; |
| import java.util.Arrays; |
| |
| import org.eclipse.jgit.errors.IncorrectObjectTypeException; |
| import org.eclipse.jgit.errors.MissingObjectException; |
| 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.Constants; |
| import org.eclipse.jgit.lib.NullProgressMonitor; |
| import org.eclipse.jgit.lib.ObjectId; |
| import org.eclipse.jgit.lib.ProgressMonitor; |
| import org.eclipse.jgit.revwalk.ObjectWalk; |
| import org.eclipse.jgit.revwalk.RevCommit; |
| import org.eclipse.jgit.revwalk.RevFlag; |
| import org.eclipse.jgit.revwalk.RevObject; |
| import org.eclipse.jgit.revwalk.RevWalk; |
| import org.eclipse.jgit.revwalk.filter.RevFilter; |
| |
| /** Helper class for PackWriter to do ObjectWalks with pack index bitmaps. */ |
| final class PackWriterBitmapWalker { |
| |
| private final ObjectWalk walker; |
| |
| private final BitmapIndex bitmapIndex; |
| |
| private final ProgressMonitor pm; |
| |
| private long countOfBitmapIndexMisses; |
| |
| PackWriterBitmapWalker( |
| ObjectWalk walker, BitmapIndex bitmapIndex, ProgressMonitor pm) { |
| this.walker = walker; |
| this.bitmapIndex = bitmapIndex; |
| this.pm = (pm == null) ? NullProgressMonitor.INSTANCE : pm; |
| } |
| |
| long getCountOfBitmapIndexMisses() { |
| return countOfBitmapIndexMisses; |
| } |
| |
| BitmapBuilder findObjects(Iterable<? extends ObjectId> start, BitmapBuilder seen, |
| boolean ignoreMissing) |
| throws MissingObjectException, IncorrectObjectTypeException, |
| IOException { |
| if (!ignoreMissing) { |
| return findObjectsWalk(start, seen, false); |
| } |
| |
| try { |
| return findObjectsWalk(start, seen, true); |
| } catch (MissingObjectException ignore) { |
| // An object reachable from one of the "start"s is missing. |
| // Walk from the "start"s one at a time so it can be excluded. |
| } |
| |
| final BitmapBuilder result = bitmapIndex.newBitmapBuilder(); |
| for (ObjectId obj : start) { |
| Bitmap bitmap = bitmapIndex.getBitmap(obj); |
| if (bitmap != null) { |
| result.or(bitmap); |
| } |
| } |
| |
| for (ObjectId obj : start) { |
| if (result.contains(obj)) { |
| continue; |
| } |
| try { |
| result.or(findObjectsWalk(Arrays.asList(obj), result, false)); |
| } catch (MissingObjectException ignore) { |
| // An object reachable from this "start" is missing. |
| // |
| // This can happen when the client specified a "have" line |
| // pointing to an object that is present but unreachable: |
| // "git prune" and "git fsck" only guarantee that the object |
| // database will continue to contain all objects reachable |
| // from a ref and does not guarantee connectivity for other |
| // objects in the object database. |
| // |
| // In this situation, skip the relevant "start" and move on |
| // to the next one. |
| // |
| // TODO(czhen): Make findObjectsWalk resume the walk instead |
| // once RevWalk and ObjectWalk support that. |
| } |
| } |
| return result; |
| } |
| |
| private BitmapBuilder findObjectsWalk(Iterable<? extends ObjectId> start, BitmapBuilder seen, |
| boolean ignoreMissingStart) |
| throws MissingObjectException, IncorrectObjectTypeException, |
| IOException { |
| walker.reset(); |
| final BitmapBuilder bitmapResult = bitmapIndex.newBitmapBuilder(); |
| |
| for (ObjectId obj : start) { |
| Bitmap bitmap = bitmapIndex.getBitmap(obj); |
| if (bitmap != null) |
| bitmapResult.or(bitmap); |
| } |
| |
| boolean marked = false; |
| for (ObjectId obj : start) { |
| try { |
| if (!bitmapResult.contains(obj)) { |
| walker.markStart(walker.parseAny(obj)); |
| marked = true; |
| } |
| } catch (MissingObjectException e) { |
| if (ignoreMissingStart) |
| continue; |
| throw e; |
| } |
| } |
| |
| if (marked) { |
| if (seen == null) { |
| walker.setRevFilter(new AddToBitmapFilter(bitmapResult)); |
| } else { |
| walker.setRevFilter( |
| new AddUnseenToBitmapFilter(seen, bitmapResult)); |
| } |
| |
| while (walker.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); |
| countOfBitmapIndexMisses++; |
| } |
| |
| RevObject ro; |
| while ((ro = walker.nextObject()) != null) { |
| bitmapResult.addObject(ro, ro.getType()); |
| pm.update(1); |
| } |
| } |
| |
| return bitmapResult; |
| } |
| |
| /** |
| * A RevFilter that adds the visited commits to {@code bitmap} as a side |
| * effect. |
| * <p> |
| * When the walk hits a commit that is part of {@code bitmap}'s |
| * BitmapIndex, that entire bitmap is ORed into {@code bitmap} and the |
| * commit and its parents are marked as SEEN so that the walk does not |
| * have to visit its ancestors. This ensures the walk is very short if |
| * there is good bitmap coverage. |
| */ |
| static class AddToBitmapFilter extends RevFilter { |
| private final BitmapBuilder bitmap; |
| |
| AddToBitmapFilter(BitmapBuilder bitmap) { |
| this.bitmap = bitmap; |
| } |
| |
| @Override |
| public final boolean include(RevWalk walker, RevCommit cmit) { |
| Bitmap visitedBitmap; |
| |
| if (bitmap.contains(cmit)) { |
| // already included |
| } else if ((visitedBitmap = bitmap.getBitmapIndex() |
| .getBitmap(cmit)) != null) { |
| bitmap.or(visitedBitmap); |
| } else { |
| bitmap.addObject(cmit, Constants.OBJ_COMMIT); |
| return true; |
| } |
| |
| for (RevCommit p : cmit.getParents()) { |
| p.add(RevFlag.SEEN); |
| } |
| return false; |
| } |
| |
| @Override |
| public final RevFilter clone() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public final boolean requiresCommitBody() { |
| return false; |
| } |
| } |
| |
| /** |
| * A RevFilter that adds the visited commits to {@code bitmap} as a side |
| * effect. |
| * <p> |
| * When the walk hits a commit that is part of {@code bitmap}'s |
| * BitmapIndex, that entire bitmap is ORed into {@code bitmap} and the |
| * commit and its parents are marked as SEEN so that the walk does not |
| * have to visit its ancestors. This ensures the walk is very short if |
| * there is good bitmap coverage. |
| * <p> |
| * Commits named in {@code seen} are considered already seen. If one is |
| * encountered, that commit and its parents will be marked with the SEEN |
| * flag to prevent the walk from visiting its ancestors. |
| */ |
| static class AddUnseenToBitmapFilter extends RevFilter { |
| private final BitmapBuilder seen; |
| private final BitmapBuilder bitmap; |
| |
| AddUnseenToBitmapFilter(BitmapBuilder seen, BitmapBuilder bitmapResult) { |
| this.seen = seen; |
| this.bitmap = bitmapResult; |
| } |
| |
| @Override |
| public final boolean include(RevWalk walker, RevCommit cmit) { |
| Bitmap visitedBitmap; |
| |
| if (seen.contains(cmit) || bitmap.contains(cmit)) { |
| // already seen or included |
| } else if ((visitedBitmap = bitmap.getBitmapIndex() |
| .getBitmap(cmit)) != null) { |
| bitmap.or(visitedBitmap); |
| } else { |
| bitmap.addObject(cmit, Constants.OBJ_COMMIT); |
| return true; |
| } |
| |
| for (RevCommit p : cmit.getParents()) { |
| p.add(RevFlag.SEEN); |
| } |
| return false; |
| } |
| |
| @Override |
| public final RevFilter clone() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public final boolean requiresCommitBody() { |
| return false; |
| } |
| } |
| } |