comparison src/org/tmatesoft/hg/repo/Revlog.java @ 74:6f1b88693d48

Complete refactoring to org.tmatesoft
author Artem Tikhomirov <tikhomirov.artem@gmail.com>
date Mon, 24 Jan 2011 03:14:45 +0100
parents src/com/tmate/hgkit/ll/Revlog.java@576d6e8a09f6
children c677e1593919
comparison
equal deleted inserted replaced
73:0d279bcc4442 74:6f1b88693d48
1 /*
2 * Copyright (c) 2010-2011 TMate Software Ltd
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * For information on how to redistribute this software under
14 * the terms of a license other than GNU General Public License
15 * contact TMate Software at support@svnkit.com
16 */
17 package org.tmatesoft.hg.repo;
18
19 import static org.tmatesoft.hg.repo.HgRepository.TIP;
20
21 import java.util.Arrays;
22 import java.util.Collection;
23 import java.util.Collections;
24 import java.util.HashMap;
25 import java.util.LinkedHashSet;
26 import java.util.Map;
27 import java.util.Set;
28
29 import org.tmatesoft.hg.core.Nodeid;
30
31
32 /**
33 *
34 * @author Artem Tikhomirov
35 * @author TMate Software Ltd.
36 */
37 abstract class Revlog {
38
39 private final HgRepository hgRepo;
40 protected final RevlogStream content;
41
42 protected Revlog(HgRepository hgRepo, RevlogStream content) {
43 if (hgRepo == null) {
44 throw new IllegalArgumentException();
45 }
46 if (content == null) {
47 throw new IllegalArgumentException();
48 }
49 this.hgRepo = hgRepo;
50 this.content = content;
51 }
52
53 public final HgRepository getRepo() {
54 return hgRepo;
55 }
56
57 public int getRevisionCount() {
58 return content.revisionCount();
59 }
60
61 public int getLocalRevisionNumber(Nodeid nid) {
62 int revision = content.findLocalRevisionNumber(nid);
63 if (revision == Integer.MIN_VALUE) {
64 throw new IllegalArgumentException(String.format("%s doesn't represent a revision of %s", nid.toString(), this /*XXX HgDataFile.getPath might be more suitable here*/));
65 }
66 return revision;
67 }
68
69 // Till now, i follow approach that NULL nodeid is never part of revlog
70 public boolean isKnown(Nodeid nodeid) {
71 final int rn = content.findLocalRevisionNumber(nodeid);
72 if (Integer.MIN_VALUE == rn) {
73 return false;
74 }
75 if (rn < 0 || rn >= content.revisionCount()) {
76 // Sanity check
77 throw new IllegalStateException();
78 }
79 return true;
80 }
81
82 /**
83 * Access to revision data as is (decompressed, but otherwise unprocessed, i.e. not parsed for e.g. changeset or manifest entries)
84 * @param nodeid
85 */
86 public byte[] content(Nodeid nodeid) {
87 return content(getLocalRevisionNumber(nodeid));
88 }
89
90 /**
91 * @param revision - repo-local index of this file change (not a changelog revision number!)
92 */
93 public byte[] content(int revision) {
94 final byte[][] dataPtr = new byte[1][];
95 Revlog.Inspector insp = new Revlog.Inspector() {
96 public void next(int revisionNumber, int actualLen, int baseRevision, int linkRevision, int parent1Revision, int parent2Revision, byte[] nodeid, byte[] data) {
97 dataPtr[0] = data;
98 }
99 };
100 content.iterate(revision, revision, true, insp);
101 return dataPtr[0];
102 }
103
104 /**
105 * XXX perhaps, return value Nodeid[2] and boolean needNodeids is better (and higher level) API for this query?
106 *
107 * @param revision - revision to query parents, or {@link HgRepository#TIP}
108 * @param parentRevisions - int[2] to get local revision numbers of parents (e.g. {6, -1})
109 * @param parent1 - byte[20] or null, if parent's nodeid is not needed
110 * @param parent2 - byte[20] or null, if second parent's nodeid is not needed
111 * @return
112 */
113 public void parents(int revision, int[] parentRevisions, byte[] parent1, byte[] parent2) {
114 if (revision != TIP && !(revision >= 0 && revision < content.revisionCount())) {
115 throw new IllegalArgumentException(String.valueOf(revision));
116 }
117 if (parentRevisions == null || parentRevisions.length < 2) {
118 throw new IllegalArgumentException(String.valueOf(parentRevisions));
119 }
120 if (parent1 != null && parent1.length < 20) {
121 throw new IllegalArgumentException(parent1.toString());
122 }
123 if (parent2 != null && parent2.length < 20) {
124 throw new IllegalArgumentException(parent2.toString());
125 }
126 class ParentCollector implements Revlog.Inspector {
127 public int p1 = -1;
128 public int p2 = -1;
129 public byte[] nodeid;
130
131 public void next(int revisionNumber, int actualLen, int baseRevision, int linkRevision, int parent1Revision, int parent2Revision, byte[] nodeid, byte[] data) {
132 p1 = parent1Revision;
133 p2 = parent2Revision;
134 this.nodeid = new byte[20];
135 // nodeid arg now comes in 32 byte from (as in file format description), however upper 12 bytes are zeros.
136 System.arraycopy(nodeid, nodeid.length > 20 ? nodeid.length - 20 : 0, this.nodeid, 0, 20);
137 }
138 };
139 ParentCollector pc = new ParentCollector();
140 content.iterate(revision, revision, false, pc);
141 parentRevisions[0] = pc.p1;
142 parentRevisions[1] = pc.p2;
143 if (parent1 != null) {
144 if (parentRevisions[0] == -1) {
145 Arrays.fill(parent1, 0, 20, (byte) 0);
146 } else {
147 content.iterate(parentRevisions[0], parentRevisions[0], false, pc);
148 System.arraycopy(pc.nodeid, 0, parent1, 0, 20);
149 }
150 }
151 if (parent2 != null) {
152 if (parentRevisions[1] == -1) {
153 Arrays.fill(parent2, 0, 20, (byte) 0);
154 } else {
155 content.iterate(parentRevisions[1], parentRevisions[1], false, pc);
156 System.arraycopy(pc.nodeid, 0, parent2, 0, 20);
157 }
158 }
159 }
160
161 // FIXME byte[] data might be too expensive, for few usecases it may be better to have intermediate Access object (when we don't need full data
162 // instantly - e.g. calculate hash, or comparing two revisions
163 // XXX seems that RevlogStream is better place for this class.
164 public interface Inspector {
165 // XXX boolean retVal to indicate whether to continue?
166 // TODO specify nodeid and data length, and reuse policy (i.e. if revlog stream doesn't reuse nodeid[] for each call)
167 void next(int revisionNumber, int actualLen, int baseRevision, int linkRevision, int parent1Revision, int parent2Revision, byte[/*20*/] nodeid, byte[] data);
168 }
169
170 /*
171 * XXX think over if it's better to do either:
172 * pw = getChangelog().new ParentWalker(); pw.init() and pass pw instance around as needed
173 * or
174 * add Revlog#getParentWalker(), static class, make cons() and #init package-local, and keep SoftReference to allow walker reuse.
175 *
176 * and yes, walker is not a proper name
177 */
178 public final class ParentWalker {
179 private Map<Nodeid, Nodeid> firstParent;
180 private Map<Nodeid, Nodeid> secondParent;
181 private Set<Nodeid> allNodes;
182
183 public ParentWalker() {
184 firstParent = secondParent = Collections.emptyMap();
185 allNodes = Collections.emptySet();
186 }
187
188 public void init() {
189 final RevlogStream stream = Revlog.this.content;
190 final int revisionCount = stream.revisionCount();
191 firstParent = new HashMap<Nodeid, Nodeid>(revisionCount);
192 secondParent = new HashMap<Nodeid, Nodeid>(firstParent.size() >> 1); // assume branches/merges are less frequent
193 allNodes = new LinkedHashSet<Nodeid>();
194
195 Inspector insp = new Inspector() {
196 final Nodeid[] sequentialRevisionNodeids = new Nodeid[revisionCount];
197 int ix = 0;
198 public void next(int revisionNumber, int actualLen, int baseRevision, int linkRevision, int parent1Revision, int parent2Revision, byte[] nodeid, byte[] data) {
199 if (ix != revisionNumber) {
200 // XXX temp code, just to make sure I understand what's going on here
201 throw new IllegalStateException();
202 }
203 if (parent1Revision >= revisionNumber || parent2Revision >= revisionNumber) {
204 throw new IllegalStateException(); // sanity, revisions are sequential
205 }
206 final Nodeid nid = new Nodeid(nodeid, true);
207 sequentialRevisionNodeids[ix++] = nid;
208 allNodes.add(nid);
209 if (parent1Revision != -1) {
210 firstParent.put(nid, sequentialRevisionNodeids[parent1Revision]);
211 if (parent2Revision != -1) {
212 secondParent.put(nid, sequentialRevisionNodeids[parent2Revision]);
213 }
214 }
215 }
216 };
217 stream.iterate(0, -1, false, insp);
218 }
219
220 public Set<Nodeid> allNodes() {
221 return Collections.unmodifiableSet(allNodes);
222 }
223
224 // FIXME need to decide whether Nodeid(00 * 20) is always known or not
225 public boolean knownNode(Nodeid nid) {
226 return allNodes.contains(nid);
227 }
228
229 // null if none
230 public Nodeid firstParent(Nodeid nid) {
231 return firstParent.get(nid);
232 }
233
234 // never null, Nodeid.NULL if none known
235 public Nodeid safeFirstParent(Nodeid nid) {
236 Nodeid rv = firstParent(nid);
237 return rv == null ? Nodeid.NULL : rv;
238 }
239
240 public Nodeid secondParent(Nodeid nid) {
241 return secondParent.get(nid);
242 }
243
244 public Nodeid safeSecondParent(Nodeid nid) {
245 Nodeid rv = secondParent(nid);
246 return rv == null ? Nodeid.NULL : rv;
247 }
248
249 public boolean appendParentsOf(Nodeid nid, Collection<Nodeid> c) {
250 Nodeid p1 = firstParent(nid);
251 boolean modified = false;
252 if (p1 != null) {
253 modified = c.add(p1);
254 Nodeid p2 = secondParent(nid);
255 if (p2 != null) {
256 modified = c.add(p2) || modified;
257 }
258 }
259 return modified;
260 }
261 }
262 }