1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
/*
* 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.revwalk;
import java.io.IOException;
import java.util.Arrays;
import org.eclipse.jgit.errors.IncorrectObjectTypeException;
import org.eclipse.jgit.errors.MissingObjectException;
import org.eclipse.jgit.internal.revwalk.AddToBitmapFilter;
import org.eclipse.jgit.internal.revwalk.AddUnseenToBitmapFilter;
import org.eclipse.jgit.lib.AnyObjectId;
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.NullProgressMonitor;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ProgressMonitor;
import org.eclipse.jgit.revwalk.filter.ObjectFilter;
/**
* Helper class to do ObjectWalks with pack index bitmaps.
*
* @since 4.10
*/
public final class BitmapWalker {
private final ObjectWalk walker;
private final BitmapIndex bitmapIndex;
private final ProgressMonitor pm;
private long countOfBitmapIndexMisses;
/**
* Create a BitmapWalker.
*
* @param walker walker to use when traversing the object graph.
* @param bitmapIndex index to obtain bitmaps from.
* @param pm progress monitor to report progress on.
*/
public BitmapWalker(
ObjectWalk walker, BitmapIndex bitmapIndex, ProgressMonitor pm) {
this.walker = walker;
this.bitmapIndex = bitmapIndex;
this.pm = (pm == null) ? NullProgressMonitor.INSTANCE : pm;
}
/**
* Return the number of objects that had to be walked because they were not covered by a
* bitmap.
*
* @return the number of objects that had to be walked because they were not covered by a
* bitmap.
*/
public long getCountOfBitmapIndexMisses() {
return countOfBitmapIndexMisses;
}
/**
* Return, as a bitmap, the objects reachable from the objects in start.
*
* @param start
* the objects to start the object traversal from.
* @param seen
* the objects to skip if encountered during traversal.
* @param ignoreMissing
* true to ignore missing objects, false otherwise.
* @return as a bitmap, the objects reachable from the objects in start.
* @throws org.eclipse.jgit.errors.MissingObjectException
* the object supplied is not available from the object
* database. This usually indicates the supplied object is
* invalid, but the reference was constructed during an earlier
* invocation to
* {@link org.eclipse.jgit.revwalk.RevWalk#lookupAny(AnyObjectId, int)}.
* @throws org.eclipse.jgit.errors.IncorrectObjectTypeException
* the object was not parsed yet and it was discovered during
* parsing that it is not actually the type of the instance
* passed in. This usually indicates the caller used the wrong
* type in a
* {@link org.eclipse.jgit.revwalk.RevWalk#lookupAny(AnyObjectId, int)}
* call.
* @throws java.io.IOException
* a pack file or loose object could not be read.
*/
public 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));
}
walker.setObjectFilter(new BitmapObjectFilter(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;
}
/**
* Filter that excludes objects already in the given bitmap.
*/
static class BitmapObjectFilter extends ObjectFilter {
private final BitmapBuilder bitmap;
BitmapObjectFilter(BitmapBuilder bitmap) {
this.bitmap = bitmap;
}
@Override
public final boolean include(ObjectWalk walker, AnyObjectId objid)
throws MissingObjectException, IncorrectObjectTypeException,
IOException {
return !bitmap.contains(objid);
}
}
}
|
