/*
* Copyright (c) 2010-2013 TMate Software Ltd
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* For information on how to redistribute this software under
* the terms of a license other than GNU General Public License
* contact TMate Software at support@hg4j.com
*/
package org.tmatesoft.hg.internal;
import static org.tmatesoft.hg.core.Nodeid.NULL;
import static org.tmatesoft.hg.repo.HgRepositoryFiles.Branch;
import static org.tmatesoft.hg.repo.HgRepositoryFiles.Dirstate;
import static org.tmatesoft.hg.util.LogFacility.Severity.Debug;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import org.tmatesoft.hg.core.Nodeid;
import org.tmatesoft.hg.repo.HgDirstate;
import org.tmatesoft.hg.repo.HgDirstate.EntryKind;
import org.tmatesoft.hg.repo.HgInvalidControlFileException;
import org.tmatesoft.hg.repo.HgRepository;
import org.tmatesoft.hg.util.LogFacility.Severity;
import org.tmatesoft.hg.util.Pair;
import org.tmatesoft.hg.util.Path;
/**
* Parse dirstate file
*
* @see http://mercurial.selenic.com/wiki/DirState
* @see http://mercurial.selenic.com/wiki/FileFormats#dirstate
*
* @author Artem Tikhomirov
* @author TMate Software Ltd.
*/
public final class DirstateReader {
// dirstate read code originally lived in org.tmatesoft.hg.repo.HgDirstate
private final Internals repo;
private final Path.Source pathPool;
private Pair<Nodeid, Nodeid> parents;
public DirstateReader(Internals hgRepo, Path.Source pathSource) {
repo = hgRepo;
pathPool = pathSource;
}
public void readInto(HgDirstate.Inspector target) throws HgInvalidControlFileException {
EncodingHelper encodingHelper = repo.buildFileNameEncodingHelper();
parents = new Pair<Nodeid,Nodeid>(Nodeid.NULL, Nodeid.NULL);
File dirstateFile = getDirstateFile(repo);
if (dirstateFile == null || !dirstateFile.exists()) {
return;
}
DataAccess da = repo.getDataAccess().createReader(dirstateFile, false);
try {
if (da.isEmpty()) {
return;
}
parents = internalReadParents(da);
// hg init; hg up produces an empty repository where dirstate has parents (40 bytes) only
while (!da.isEmpty()) {
final byte state = da.readByte();
final int fmode = da.readInt();
final int size = da.readInt();
final int time = da.readInt();
final int nameLen = da.readInt();
String fn1 = null, fn2 = null;
byte[] name = new byte[nameLen];
da.readBytes(name, 0, nameLen);
for (int i = 0; i < nameLen; i++) {
if (name[i] == 0) {
fn1 = encodingHelper.fromDirstate(name, 0, i);
fn2 = encodingHelper.fromDirstate(name, i+1, nameLen - i - 1);
break;
}
}
if (fn1 == null) {
fn1 = encodingHelper.fromDirstate(name, 0, nameLen);
}
HgDirstate.Record r = new HgDirstate.Record(fmode, size, time, pathPool.path(fn1), fn2 == null ? null : pathPool.path(fn2));
if (state == 'n') {
target.next(EntryKind.Normal, r);
} else if (state == 'a') {
target.next(EntryKind.Added, r);
} else if (state == 'r') {
target.next(EntryKind.Removed, r);
} else if (state == 'm') {
target.next(EntryKind.Merged, r);
} else {
repo.getLog().dump(getClass(), Severity.Warn, "Dirstate record for file %s (size: %d, tstamp:%d) has unknown state '%c'", r.name(), r.size(), r.modificationTime(), state);
}
}
} catch (IOException ex) {
throw new HgInvalidControlFileException("Dirstate read failed", ex, dirstateFile);
} finally {
da.done();
}
}
private static Pair<Nodeid, Nodeid> internalReadParents(DataAccess da) throws IOException {
byte[] parents = new byte[40];
da.readBytes(parents, 0, 40);
Nodeid n1 = Nodeid.fromBinary(parents, 0);
Nodeid n2 = Nodeid.fromBinary(parents, 20);
parents = null;
return new Pair<Nodeid, Nodeid>(n1, n2);
}
/**
* @return pair of working copy parents, with {@link Nodeid#NULL} for missing values.
*/
public Pair<Nodeid,Nodeid> parents() {
assert parents != null; // instance not initialized with #read()
return parents;
}
private static File getDirstateFile(Internals repo) {
return repo.getFileFromRepoDir(Dirstate.getName());
}
/**
* @return pair of parents, both {@link Nodeid#NULL} if dirstate is not available
*/
public static Pair<Nodeid, Nodeid> readParents(Internals internalRepo) throws HgInvalidControlFileException {
// do not read whole dirstate if all we need is WC parent information
File dirstateFile = getDirstateFile(internalRepo);
if (dirstateFile == null || !dirstateFile.exists()) {
return new Pair<Nodeid,Nodeid>(NULL, NULL);
}
DataAccess da = internalRepo.getDataAccess().createReader(dirstateFile, false);
try {
if (da.isEmpty()) {
return new Pair<Nodeid,Nodeid>(NULL, NULL);
}
return internalReadParents(da);
} catch (IOException ex) {
throw new HgInvalidControlFileException("Error reading working copy parents from dirstate", ex, dirstateFile);
} finally {
da.done();
}
}
/**
* TODO [post-1.0] it's really not a proper place for the method, need WorkingCopyContainer or similar
* @return branch associated with the working directory
*/
public static String readBranch(Internals internalRepo) throws HgInvalidControlFileException {
File branchFile = internalRepo.getRepositoryFile(Branch);
String branch = HgRepository.DEFAULT_BRANCH_NAME;
if (branchFile.exists()) {
try {
// branch file is UTF-8 encoded, see http://mercurial.selenic.com/wiki/EncodingStrategy#UTF-8_strings
// shall not use system-default encoding (FileReader) when reading it!
// Perhaps, shall use EncodingHelper.fromBranch and InputStream instead, for uniformity?
// Since whole file is in UTF8, InputStreamReader is a convenience over InputStream,
// which we use elsewhere (together with EncodingHelper) - other files are usually a mix of binary data
// and encoded text (hence, InputStreamReader with charset is not an option there)
BufferedReader r = new BufferedReader(new InputStreamReader(new FileInputStream(branchFile), EncodingHelper.getUTF8()));
String b = r.readLine();
if (b != null) {
b = b.trim().intern();
}
branch = b == null || b.length() == 0 ? HgRepository.DEFAULT_BRANCH_NAME : b;
r.close();
} catch (FileNotFoundException ex) {
internalRepo.getLog().dump(HgDirstate.class, Debug, ex, null); // log verbose debug, exception might be legal here
// IGNORE
} catch (IOException ex) {
throw new HgInvalidControlFileException("Error reading file with branch information", ex, branchFile);
}
}
return branch;
}
}