/*
* Copyright (C) 2009, Google Inc.
* Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
*
* 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 Git Development Community 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.spearce.jgit.revwalk;
import java.io.IOException;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.spearce.jgit.errors.IncorrectObjectTypeException;
import org.spearce.jgit.errors.MissingObjectException;
import org.spearce.jgit.lib.AnyObjectId;
import org.spearce.jgit.lib.Commit;
import org.spearce.jgit.lib.Constants;
import org.spearce.jgit.lib.MutableObjectId;
import org.spearce.jgit.lib.PersonIdent;
import org.spearce.jgit.util.RawParseUtils;
/** A commit reference to a commit in the DAG. */
public class RevCommit extends RevObject {
static final RevCommit[] NO_PARENTS = {};
private RevTree tree;
RevCommit[] parents;
int commitTime; // An int here for performance, overflows in 2038
int inDegree;
private byte[] buffer;
/**
* Create a new commit reference.
*
* @param id
* object name for the commit.
*/
protected RevCommit(final AnyObjectId id) {
super(id);
}
@Override
void parseHeaders(final RevWalk walk) throws MissingObjectException,
IncorrectObjectTypeException, IOException {
parseCanonical(walk, loadCanonical(walk));
}
@Override
void parseBody(final RevWalk walk) throws MissingObjectException,
IncorrectObjectTypeException, IOException {
if (buffer == null) {
buffer = loadCanonical(walk);
if ((flags & PARSED) == 0)
parseCanonical(walk, buffer);
}
}
void parseCanonical(final RevWalk walk, final byte[] raw) {
final MutableObjectId idBuffer = walk.idBuffer;
idBuffer.fromString(raw, 5);
tree = walk.lookupTree(idBuffer);
int ptr = 46;
if (parents == null) {
RevCommit[] pList = new RevCommit[1];
int nParents = 0;
for (;;) {
if (raw[ptr] != 'p')
break;
idBuffer.fromString(raw, ptr + 7);
final RevCommit p = walk.lookupCommit(idBuffer);
if (nParents == 0)
pList[nParents++] = p;
else if (nParents == 1) {
pList = new RevCommit[] { pList[0], p };
nParents = 2;
} else {
if (pList.length <= nParents) {
RevCommit[] old = pList;
pList = new RevCommit[pList.length + 32];
System.arraycopy(old, 0, pList, 0, nParents);
}
pList[nParents++] = p;
}
ptr += 48;
}
if (nParents != pList.length) {
RevCommit[] old = pList;
pList = new RevCommit[nParents];
System.arraycopy(old, 0, pList, 0, nParents);
}
parents = pList;
}
// extract time from "committer "
ptr = RawParseUtils.committer(raw, ptr);
if (ptr > 0) {
ptr = RawParseUtils.nextLF(raw, ptr, '>');
// In 2038 commitTime will overflow unless it is changed to long.
commitTime = RawParseUtils.parseBase10(raw, ptr, null);
}
if (walk.isRetainBody())
buffer = raw;
flags |= PARSED;
}
@Override
public final int getType() {
return Constants.OBJ_COMMIT;
}
static void carryFlags(RevCommit c, final int carry) {
for (;;) {
final RevCommit[] pList = c.parents;
if (pList == null)
return;
final int n = pList.length;
if (n == 0)
return;
for (int i = 1; i < n; i++) {
final RevCommit p = pList[i];
if ((p.flags & carry) == carry)
continue;
p.flags |= carry;
carryFlags(p, carry);
}
c = pList[0];
if ((c.flags & carry) == carry)
return;
c.flags |= carry;
}
}
/**
* Carry a RevFlag set on this commit to its parents.
* <p>
* If this commit is parsed, has parents, and has the supplied flag set on
* it we automatically add it to the parents, grand-parents, and so on until
* an unparsed commit or a commit with no parents is discovered. This
* permits applications to force a flag through the history chain when
* necessary.
*
* @param flag
* the single flag value to carry back onto parents.
*/
public void carry(final RevFlag flag) {
final int carry = flags & flag.mask;
if (carry != 0)
carryFlags(this, carry);
}
/**
* Time from the "committer " line of the buffer.
*
* @return time, expressed as seconds since the epoch.
*/
public final int getCommitTime() {
return commitTime;
}
/**
* Parse this commit buffer for display.
*
* @param walk
* revision walker owning this reference.
* @return parsed commit.
*/
public final Commit asCommit(final RevWalk walk) {
return new Commit(walk.db, this, buffer);
}
/**
* Get a reference to this commit's tree.
*
* @return tree of this commit.
*/
public final RevTree getTree() {
return tree;
}
/**
* Get the number of parent commits listed in this commit.
*
* @return number of parents; always a positive value but can be 0.
*/
public final int getParentCount() {
return parents.length;
}
/**
* Get the nth parent from this commit's parent list.
*
* @param nth
* parent index to obtain. Must be in the range 0 through
* {@link #getParentCount()}-1.
* @return the specified parent.
* @throws ArrayIndexOutOfBoundsException
* an invalid parent index was specified.
*/
public final RevCommit getParent(final int nth) {
return parents[nth];
}
/**
* Obtain an array of all parents (<b>NOTE - THIS IS NOT A COPY</b>).
* <p>
* This method is exposed only to provide very fast, efficient access to
* this commit's parent list. Applications relying on this list should be
* very careful to ensure they do not modify its contents during their use
* of it.
*
* @return the array of parents.
*/
public final RevCommit[] getParents() {
return parents;
}
/**
* Obtain the raw unparsed commit body (<b>NOTE - THIS IS NOT A COPY</b>).
* <p>
* This method is exposed only to provide very fast, efficient access to
* this commit's message buffer within a RevFilter. Applications relying on
* this buffer should be very careful to ensure they do not modify its
* contents during their use of it.
*
* @return the raw unparsed commit body. This is <b>NOT A COPY</b>.
* Altering the contents of this buffer may alter the walker's
* knowledge of this commit, and the results it produces.
*/
public final byte[] getRawBuffer() {
return buffer;
}
/**
* Parse the author identity from the raw buffer.
* <p>
* This method parses and returns the content of the author line, after
* taking the commit's character set into account and decoding the author
* name and email address. This method is fairly expensive and produces a
* new PersonIdent instance on each invocation. Callers should invoke this
* method only if they are certain they will be outputting the result, and
* should cache the return value for as long as necessary to use all
* information from it.
* <p>
* RevFilter implementations should try to use {@link RawParseUtils} to scan
* the {@link #getRawBuffer()} instead, as this will allow faster evaluation
* of commits.
*
* @return identity of the author (name, email) and the time the commit was
* made by the author; null if no author line was found.
*/
public final PersonIdent getAuthorIdent() {
final byte[] raw = buffer;
final int nameB = RawParseUtils.author(raw, 0);
if (nameB < 0)
return null;
return RawParseUtils.parsePersonIdent(raw, nameB);
}
/**
* Parse the committer identity from the raw buffer.
* <p>
* This method parses and returns the content of the committer line, after
* taking the commit's character set into account and decoding the committer
* name and email address. This method is fairly expensive and produces a
* new PersonIdent instance on each invocation. Callers should invoke this
* method only if they are certain they will be outputting the result, and
* should cache the return value for as long as necessary to use all
* information from it.
* <p>
* RevFilter implementations should try to use {@link RawParseUtils} to scan
* the {@link #getRawBuffer()} instead, as this will allow faster evaluation
* of commits.
*
* @return identity of the committer (name, email) and the time the commit
* was made by the committer; null if no committer line was found.
*/
public final PersonIdent getCommitterIdent() {
final byte[] raw = buffer;
final int nameB = RawParseUtils.committer(raw, 0);
if (nameB < 0)
return null;
return RawParseUtils.parsePersonIdent(raw, nameB);
}
/**
* Parse the complete commit message and decode it to a string.
* <p>
* This method parses and returns the message portion of the commit buffer,
* after taking the commit's character set into account and decoding the
* buffer using that character set. This method is a fairly expensive
* operation and produces a new string on each invocation.
*
* @return decoded commit message as a string. Never null.
*/
public final String getFullMessage() {
final byte[] raw = buffer;
final int msgB = RawParseUtils.commitMessage(raw, 0);
if (msgB < 0)
return "";
final Charset enc = RawParseUtils.parseEncoding(raw);
return RawParseUtils.decode(enc, raw, msgB, raw.length);
}
/**
* Parse the commit message and return the first "line" of it.
* <p>
* The first line is everything up to the first pair of LFs. This is the
* "oneline" format, suitable for output in a single line display.
* <p>
* This method parses and returns the message portion of the commit buffer,
* after taking the commit's character set into account and decoding the
* buffer using that character set. This method is a fairly expensive
* operation and produces a new string on each invocation.
*
* @return decoded commit message as a string. Never null. The returned
* string does not contain any LFs, even if the first paragraph
* spanned multiple lines. Embedded LFs are converted to spaces.
*/
public final String getShortMessage() {
final byte[] raw = buffer;
final int msgB = RawParseUtils.commitMessage(raw, 0);
if (msgB < 0)
return "";
final Charset enc = RawParseUtils.parseEncoding(raw);
final int msgE = RawParseUtils.endOfParagraph(raw, msgB);
String str = RawParseUtils.decode(enc, raw, msgB, msgE);
if (hasLF(raw, msgB, msgE))
str = str.replace('\n', ' ');
return str;
}
static boolean hasLF(final byte[] r, int b, final int e) {
while (b < e)
if (r[b++] == '\n')
return true;
return false;
}
/**
* Determine the encoding of the commit message buffer.
* <p>
* Locates the "encoding" header (if present) and then returns the proper
* character set to apply to this buffer to evaluate its contents as
* character data.
* <p>
* If no encoding header is present, {@link Constants#CHARSET} is assumed.
*
* @return the preferred encoding of {@link #getRawBuffer()}.
*/
public final Charset getEncoding() {
return RawParseUtils.parseEncoding(buffer);
}
/**
* Parse the footer lines (e.g. "Signed-off-by") for machine processing.
* <p>
* This method splits all of the footer lines out of the last paragraph of
* the commit message, providing each line as a key-value pair, ordered by
* the order of the line's appearance in the commit message itself.
* <p>
* A footer line's key must match the pattern {@code ^[A-Za-z0-9-]+:}, while
* the value is free-form, but must not contain an LF. Very common keys seen
* in the wild are:
* <ul>
* <li>{@code Signed-off-by} (agrees to Developer Certificate of Origin)
* <li>{@code Acked-by} (thinks change looks sane in context)
* <li>{@code Reported-by} (originally found the issue this change fixes)
* <li>{@code Tested-by} (validated change fixes the issue for them)
* <li>{@code CC}, {@code Cc} (copy on all email related to this change)
* <li>{@code Bug} (link to project's bug tracking system)
* </ul>
*
* @return ordered list of footer lines; empty list if no footers found.
*/
public final List<FooterLine> getFooterLines() {
final byte[] raw = buffer;
int ptr = raw.length - 1;
while (raw[ptr] == '\n') // trim any trailing LFs, not interesting
ptr--;
final int msgB = RawParseUtils.commitMessage(raw, 0);
final ArrayList<FooterLine> r = new ArrayList<FooterLine>(4);
final Charset enc = getEncoding();
for (;;) {
ptr = RawParseUtils.prevLF(raw, ptr);
if (ptr <= msgB)
break; // Don't parse commit headers as footer lines.
final int keyStart = ptr + 2;
if (raw[keyStart] == '\n')
break; // Stop at first paragraph break, no footers above it.
final int keyEnd = RawParseUtils.endOfFooterLineKey(raw, keyStart);
if (keyEnd < 0)
continue; // Not a well formed footer line, skip it.
// Skip over the ': *' at the end of the key before the value.
//
int valStart = keyEnd + 1;
while (valStart < raw.length && raw[valStart] == ' ')
valStart++;
// Value ends at the LF, and does not include it.
//
int valEnd = RawParseUtils.nextLF(raw, valStart);
if (raw[valEnd - 1] == '\n')
valEnd--;
r.add(new FooterLine(raw, enc, keyStart, keyEnd, valStart, valEnd));
}
Collections.reverse(r);
return r;
}
/**
* Get the values of all footer lines with the given key.
*
* @param keyName
* footer key to find values of, case insensitive.
* @return values of footers with key of {@code keyName}, ordered by their
* order of appearance. Duplicates may be returned if the same
* footer appeared more than once. Empty list if no footers appear
* with the specified key, or there are no footers at all.
* @see #getFooterLines()
*/
public final List<String> getFooterLines(final String keyName) {
return getFooterLines(new FooterKey(keyName));
}
/**
* Get the values of all footer lines with the given key.
*
* @param keyName
* footer key to find values of, case insensitive.
* @return values of footers with key of {@code keyName}, ordered by their
* order of appearance. Duplicates may be returned if the same
* footer appeared more than once. Empty list if no footers appear
* with the specified key, or there are no footers at all.
* @see #getFooterLines()
*/
public final List<String> getFooterLines(final FooterKey keyName) {
final List<FooterLine> src = getFooterLines();
if (src.isEmpty())
return Collections.emptyList();
final ArrayList<String> r = new ArrayList<String>(src.size());
for (final FooterLine f : src) {
if (f.matches(keyName))
r.add(f.getValue());
}
return r;
}
/**
* Reset this commit to allow another RevWalk with the same instances.
* <p>
* Subclasses <b>must</b> call <code>super.reset()</code> to ensure the
* basic information can be correctly cleared out.
*/
public void reset() {
inDegree = 0;
}
final void disposeBody() {
buffer = null;
}
@Override
public String toString() {
final StringBuilder s = new StringBuilder();
s.append(Constants.typeString(getType()));
s.append(' ');
s.append(name());
s.append(' ');
s.append(commitTime);
s.append(' ');
appendCoreFlags(s);
return s.toString();
}
}