1 /* 2 * Copyright (C) 2008-2009, Google Inc. 3 * Copyright (C) 2008, Marek Zawirski <marek.zawirski@gmail.com> 4 * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> 5 * and other copyright owners as documented in the project's IP log. 6 * 7 * This program and the accompanying materials are made available 8 * under the terms of the Eclipse Distribution License v1.0 which 9 * accompanies this distribution, is reproduced below, and is 10 * available at http://www.eclipse.org/org/documents/edl-v10.php 11 * 12 * All rights reserved. 13 * 14 * Redistribution and use in source and binary forms, with or 15 * without modification, are permitted provided that the following 16 * conditions are met: 17 * 18 * - Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 21 * - Redistributions in binary form must reproduce the above 22 * copyright notice, this list of conditions and the following 23 * disclaimer in the documentation and/or other materials provided 24 * with the distribution. 25 * 26 * - Neither the name of the Eclipse Foundation, Inc. nor the 27 * names of its contributors may be used to endorse or promote 28 * products derived from this software without specific prior 29 * written permission. 30 * 31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 32 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 33 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 34 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 35 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 36 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 37 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 38 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 39 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 40 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 41 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 42 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 43 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 44 */ 45 46 package org.eclipse.jgit.revwalk; 47 48 import java.io.IOException; 49 import java.nio.charset.Charset; 50 51 import org.eclipse.jgit.errors.CorruptObjectException; 52 import org.eclipse.jgit.errors.IncorrectObjectTypeException; 53 import org.eclipse.jgit.errors.MissingObjectException; 54 import org.eclipse.jgit.lib.AnyObjectId; 55 import org.eclipse.jgit.lib.Constants; 56 import org.eclipse.jgit.lib.ObjectInserter; 57 import org.eclipse.jgit.lib.ObjectReader; 58 import org.eclipse.jgit.lib.PersonIdent; 59 import org.eclipse.jgit.util.MutableInteger; 60 import org.eclipse.jgit.util.RawParseUtils; 61 import org.eclipse.jgit.util.StringUtils; 62 63 /** An annotated tag. */ 64 public class RevTag extends RevObject { 65 /** 66 * Parse an annotated tag from its canonical format. 67 * 68 * This method constructs a temporary revision pool, parses the tag as 69 * supplied, and returns it to the caller. Since the tag was built inside of 70 * a private revision pool its object pointer will be initialized, but will 71 * not have its headers loaded. 72 * 73 * Applications are discouraged from using this API. Callers usually need 74 * more than one object. Use {@link RevWalk#parseTag(AnyObjectId)} to obtain 75 * a RevTag from an existing repository. 76 * 77 * @param raw 78 * the canonical formatted tag to be parsed. 79 * @return the parsed tag, in an isolated revision pool that is not 80 * available to the caller. 81 * @throws CorruptObjectException 82 * the tag contains a malformed header that cannot be handled. 83 */ 84 public static RevTag parse(byte[] raw) throws CorruptObjectException { 85 return parse(new RevWalk((ObjectReader) null), raw); 86 } 87 88 /** 89 * Parse an annotated tag from its canonical format. 90 * <p> 91 * This method inserts the tag directly into the caller supplied revision 92 * pool, making it appear as though the tag exists in the repository, even 93 * if it doesn't. The repository under the pool is not affected. 94 * <p> 95 * The body of the tag (message, tagger, signature) is always retained in 96 * the returned {@code RevTag}, even if the supplied {@code RevWalk} has 97 * been configured with {@code setRetainBody(false)}. 98 * 99 * @param rw 100 * the revision pool to allocate the tag within. The tag's object 101 * pointer will be obtained from this pool. 102 * @param raw 103 * the canonical formatted tag to be parsed. This buffer will be 104 * retained by the returned {@code RevTag} and must not be 105 * modified by the caller. 106 * @return the parsed tag, in an isolated revision pool that is not 107 * available to the caller. 108 * @throws CorruptObjectException 109 * the tag contains a malformed header that cannot be handled. 110 */ 111 public static RevTag parse(RevWalk rw, byte[] raw) 112 throws CorruptObjectException { 113 try (ObjectInserter.Formatter fmt = new ObjectInserter.Formatter()) { 114 RevTag r = rw.lookupTag(fmt.idFor(Constants.OBJ_TAG, raw)); 115 r.parseCanonical(rw, raw); 116 r.buffer = raw; 117 return r; 118 } 119 } 120 121 private RevObject object; 122 123 private byte[] buffer; 124 125 private String tagName; 126 127 /** 128 * Create a new tag reference. 129 * 130 * @param id 131 * object name for the tag. 132 */ 133 protected RevTag(final AnyObjectId id) { 134 super(id); 135 } 136 137 @Override 138 void parseHeaders(final RevWalk walk) throws MissingObjectException, 139 IncorrectObjectTypeException, IOException { 140 parseCanonical(walk, walk.getCachedBytes(this)); 141 } 142 143 @Override 144 void parseBody(final RevWalk walk) throws MissingObjectException, 145 IncorrectObjectTypeException, IOException { 146 if (buffer == null) { 147 buffer = walk.getCachedBytes(this); 148 if ((flags & PARSED) == 0) 149 parseCanonical(walk, buffer); 150 } 151 } 152 153 void parseCanonical(final RevWalk walk, final byte[] rawTag) 154 throws CorruptObjectException { 155 final MutableInteger pos = new MutableInteger(); 156 final int oType; 157 158 pos.value = 53; // "object $sha1\ntype " 159 oType = Constants.decodeTypeString(this, rawTag, (byte) '\n', pos); 160 walk.idBuffer.fromString(rawTag, 7); 161 object = walk.lookupAny(walk.idBuffer, oType); 162 163 int p = pos.value += 4; // "tag " 164 final int nameEnd = RawParseUtils.nextLF(rawTag, p) - 1; 165 tagName = RawParseUtils.decode(Constants.CHARSET, rawTag, p, nameEnd); 166 167 if (walk.isRetainBody()) 168 buffer = rawTag; 169 flags |= PARSED; 170 } 171 172 @Override 173 public final int getType() { 174 return Constants.OBJ_TAG; 175 } 176 177 /** 178 * Parse the tagger identity from the raw buffer. 179 * <p> 180 * This method parses and returns the content of the tagger line, after 181 * taking the tag's character set into account and decoding the tagger 182 * name and email address. This method is fairly expensive and produces a 183 * new PersonIdent instance on each invocation. Callers should invoke this 184 * method only if they are certain they will be outputting the result, and 185 * should cache the return value for as long as necessary to use all 186 * information from it. 187 * 188 * @return identity of the tagger (name, email) and the time the tag 189 * was made by the tagger; null if no tagger line was found. 190 */ 191 public final PersonIdent getTaggerIdent() { 192 final byte[] raw = buffer; 193 final int nameB = RawParseUtils.tagger(raw, 0); 194 if (nameB < 0) 195 return null; 196 return RawParseUtils.parsePersonIdent(raw, nameB); 197 } 198 199 /** 200 * Parse the complete tag message and decode it to a string. 201 * <p> 202 * This method parses and returns the message portion of the tag buffer, 203 * after taking the tag's character set into account and decoding the buffer 204 * using that character set. This method is a fairly expensive operation and 205 * produces a new string on each invocation. 206 * 207 * @return decoded tag message as a string. Never null. 208 */ 209 public final String getFullMessage() { 210 final byte[] raw = buffer; 211 final int msgB = RawParseUtils.tagMessage(raw, 0); 212 if (msgB < 0) 213 return ""; //$NON-NLS-1$ 214 final Charset enc = RawParseUtils.parseEncoding(raw); 215 return RawParseUtils.decode(enc, raw, msgB, raw.length); 216 } 217 218 /** 219 * Parse the tag message and return the first "line" of it. 220 * <p> 221 * The first line is everything up to the first pair of LFs. This is the 222 * "oneline" format, suitable for output in a single line display. 223 * <p> 224 * This method parses and returns the message portion of the tag buffer, 225 * after taking the tag's character set into account and decoding the buffer 226 * using that character set. This method is a fairly expensive operation and 227 * produces a new string on each invocation. 228 * 229 * @return decoded tag message as a string. Never null. The returned string 230 * does not contain any LFs, even if the first paragraph spanned 231 * multiple lines. Embedded LFs are converted to spaces. 232 */ 233 public final String getShortMessage() { 234 final byte[] raw = buffer; 235 final int msgB = RawParseUtils.tagMessage(raw, 0); 236 if (msgB < 0) 237 return ""; //$NON-NLS-1$ 238 239 final Charset enc = RawParseUtils.parseEncoding(raw); 240 final int msgE = RawParseUtils.endOfParagraph(raw, msgB); 241 String str = RawParseUtils.decode(enc, raw, msgB, msgE); 242 if (RevCommit.hasLF(raw, msgB, msgE)) 243 str = StringUtils.replaceLineBreaksWithSpace(str); 244 return str; 245 } 246 247 /** 248 * Get a reference to the object this tag was placed on. 249 * <p> 250 * Note that the returned object has only been looked up (see 251 * {@link RevWalk#lookupAny(AnyObjectId, int)}. To access the contents it 252 * needs to be parsed, see {@link RevWalk#parseHeaders(RevObject)} and 253 * {@link RevWalk#parseBody(RevObject)}. 254 * <p> 255 * As an alternative, use {@link RevWalk#peel(RevObject)} and pass this 256 * {@link RevTag} to peel it until the first non-tag object. 257 * 258 * @return object this tag refers to (only looked up, not parsed) 259 */ 260 public final RevObject getObject() { 261 return object; 262 } 263 264 /** 265 * Get the name of this tag, from the tag header. 266 * 267 * @return name of the tag, according to the tag header. 268 */ 269 public final String getTagName() { 270 return tagName; 271 } 272 273 /** 274 * Discard the message buffer to reduce memory usage. 275 * <p> 276 * After discarding the memory usage of the {@code RevTag} is reduced to 277 * only the {@link #getObject()} pointer and {@link #getTagName()}. 278 * Accessing other properties such as {@link #getTaggerIdent()} or either 279 * message function requires reloading the buffer by invoking 280 * {@link RevWalk#parseBody(RevObject)}. 281 * 282 * @since 4.0 283 */ 284 public final void disposeBody() { 285 buffer = null; 286 } 287 }