src/repository.cpp

   1 /*
   2  *  Copyright (C) 2007  Thiago Macieira <thiago@kde.org>
   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, either version 2 of the License, or
   7  *  (at your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License
  15  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "repository.h"
  19 #include <QTextStream>
  20 #include <QDebug>
  21 #include <QLinkedList>
  22
  23 static const int maxSimultaneousProcesses = 100;
  24
  25 class ProcessCache: QLinkedList<Repository *>
  26 {
  27 public:
  28     void touch(Repository *repo)
  29     {
  30         remove(repo);
  31
  32         // if the cache is too big, remove from the front
  33         while (size() >= maxSimultaneousProcesses)
  34             takeFirst()->closeFastImport();
  35
  36         // append to the end
  37         append(repo);
  38     }
  39
  40     inline void remove(Repository *repo)
  41     {
  42         removeOne(repo);
  43     }
  44 };
  45 static ProcessCache processCache;
  46
  47 Repository::Repository(const Rules::Repository &rule)
  48     : name(rule.name), commitCount(0), processHasStarted(false)
  49 {
  50     foreach (Rules::Repository::Branch branchRule, rule.branches) {
  51         Branch branch;
  52         branch.created = 0;     // not created
  53
  54         branches.insert(branchRule.name, branch);
  55     }
  56
  57     // create the default branch
  58     branches["master"].created = 1;
  59
  60     fastImport.setWorkingDirectory(name);
  61 }
  62
  63 Repository::~Repository()
  64 {
  65     closeFastImport();
  66 }
  67
  68 void Repository::closeFastImport()
  69 {
  70     if (fastImport.state() != QProcess::NotRunning) {
  71         fastImport.write("checkpoint\n");
  72         fastImport.waitForBytesWritten(-1);
  73         fastImport.closeWriteChannel();
  74         if (!fastImport.waitForFinished()) {
  75             fastImport.terminate();
  76             if (!fastImport.waitForFinished(200))
  77                 qWarning() << "git-fast-import for repository" << name << "did not die";
  78         }
  79     }
  80     processHasStarted = false;
  81     processCache.remove(this);
  82 }
  83
  84 void Repository::reloadBranches()
  85 {
  86     QProcess revParse;
  87     revParse.setWorkingDirectory(name);
  88     revParse.start("git", QStringList() << "rev-parse" << "--symbolic" << "--branches");
  89     revParse.waitForFinished(-1);
  90
  91     if (revParse.exitCode() == 0 && revParse.bytesAvailable()) {
  92         while (revParse.canReadLine()) {
  93             QByteArray branchName = revParse.readLine().trimmed();
  94
  95             //qDebug() << "Repo" << name << "reloaded branch" << branchName;
  96             branches[branchName].created = 1;
  97             fastImport.write("reset refs/heads/" + branchName +
  98                              "\nfrom refs/heads/" + branchName + "^0\n\n"
  99                              "progress Branch refs/heads/" + branchName + " reloaded\n");
 100         }
 101     }
 102 }
 103
 104 void Repository::createBranch(const QString &branch, int revnum,
 105                               const QString &branchFrom, int)
 106 {
 107     startFastImport();
 108     if (!branches.contains(branch)) {
 109         qWarning() << branch << "is not a known branch in repository" << name << endl
 110                    << "Going to create it automatically";
 111     }
 112
 113     QByteArray branchRef = branch.toUtf8();
 114     if (!branchRef.startsWith("refs/"))
 115         branchRef.prepend("refs/heads/");
 116
 117     Branch &br = branches[branch];
 118     if (br.created && br.created != revnum) {
 119         QByteArray backupBranch = branchRef + '_' + QByteArray::number(revnum);
 120         qWarning() << branch << "already exists; backing up to" << backupBranch;
 121
 122         fastImport.write("reset " + backupBranch + "\nfrom " + branchRef + "\n\n");
 123     }
 124
 125     // now create the branch
 126     br.created = revnum;
 127     QByteArray branchFromRef = branchFrom.toUtf8();
 128     if (!branchFromRef.startsWith("refs/"))
 129         branchFromRef.prepend("refs/heads/");
 130
 131     if (!branches.contains(branchFrom) || !branches.value(branchFrom).created) {
 132         qCritical() << branch << "in repository" << name
 133                     << "is branching from branch" << branchFrom
 134                     << "but the latter doesn't exist. Can't continue.";
 135         exit(1);
 136     }
 137
 138     fastImport.write("reset " + branchRef + "\nfrom " + branchFromRef + "\n\n"
 139         "progress Branch " + branchRef + " created from " + branchFromRef + "\n\n");
 140 }
 141
 142 Repository::Transaction *Repository::newTransaction(const QString &branch, const QString &svnprefix,
 143                                                     int revnum)
 144 {
 145     startFastImport();
 146     if (!branches.contains(branch)) {
 147         qWarning() << branch << "is not a known branch in repository" << name << endl
 148                    << "Going to create it automatically";
 149     }
 150
 151     Transaction *txn = new Transaction;
 152     txn->repository = this;
 153     txn->branch = branch.toUtf8();
 154     txn->svnprefix = svnprefix.toUtf8();
 155     txn->datetime = 0;
 156     txn->revnum = revnum;
 157     txn->lastmark = revnum;
 158
 159     if ((++commitCount % 10000) == 0)
 160         // write everything to disk every 10000 commits
 161         fastImport.write("checkpoint\n");
 162     return txn;
 163 }
 164
 165 void Repository::startFastImport()
 166 {
 167     if (fastImport.state() == QProcess::NotRunning) {
 168         if (processHasStarted)
 169             qFatal("git-fast-import has been started once and crashed?");
 170         processHasStarted = true;
 171
 172         // start the process
 173         QString outputFile = name;
 174         outputFile.replace('/', '_');
 175         outputFile.prepend("log-");
 176         fastImport.setStandardOutputFile(outputFile, QIODevice::Append);
 177         fastImport.setProcessChannelMode(QProcess::MergedChannels);
 178
 179 #ifndef DRY_RUN
 180         fastImport.start("git", QStringList() << "fast-import");
 181 #else
 182         fastImport.start("/bin/cat", QStringList());
 183 #endif
 184
 185         reloadBranches();
 186     }
 187 }
 188
 189 Repository::Transaction::~Transaction()
 190 {
 191 }
 192
 193 void Repository::Transaction::setAuthor(const QByteArray &a)
 194 {
 195     author = a;
 196 }
 197
 198 void Repository::Transaction::setDateTime(uint dt)
 199 {
 200     datetime = dt;
 201 }
 202
 203 void Repository::Transaction::setLog(const QByteArray &l)
 204 {
 205     log = l;
 206 }
 207
 208 void Repository::Transaction::deleteFile(const QString &path)
 209 {
 210     deletedFiles.append(path);
 211 }
 212
 213 QIODevice *Repository::Transaction::addFile(const QString &path, int mode, qint64 length)
 214 {
 215     FileProperties fp;
 216     fp.mode = mode;
 217     fp.mark = ++lastmark;
 218
 219 #ifndef DRY_RUN
 220     repository->fastImport.write("blob\nmark :");
 221     repository->fastImport.write(QByteArray::number(fp.mark));
 222     repository->fastImport.write("\ndata ");
 223     repository->fastImport.write(QByteArray::number(length));
 224     repository->fastImport.write("\n", 1);
 225 #endif
 226
 227     modifiedFiles.insert(path, fp);
 228     return &repository->fastImport;
 229 }
 230
 231 void Repository::Transaction::commit()
 232 {
 233     processCache.touch(repository);
 234
 235     // create the commit message
 236     QByteArray message = log;
 237     if (!message.endsWith('\n'))
 238         message += '\n';
 239     message += "\nsvn path=" + svnprefix + "; revision=" + QByteArray::number(revnum) + "\n";
 240
 241     {
 242         QByteArray branchRef = branch;
 243         if (!branchRef.startsWith("refs/"))
 244             branchRef.prepend("refs/heads/");
 245
 246         QTextStream s(&repository->fastImport);
 247         s << "commit " << branchRef << endl;
 248         s << "mark :" << revnum << endl;
 249         s << "committer " << QString::fromUtf8(author) << ' ' << datetime << " -0000" << endl;
 250
 251         Branch &br = repository->branches[branch];
 252         if (!br.created) {
 253             qWarning() << "Branch" << branch << "in repository" << repository->name << "doesn't exist at revision"
 254                        << revnum << "-- did you resume from the wrong revision?";
 255             br.created = revnum;
 256         }
 257
 258         s << "data " << message.length() << endl;
 259     }
 260
 261     repository->fastImport.write(message);
 262     repository->fastImport.putChar('\n');
 263
 264     // write the file deletions
 265     if (deletedFiles.contains(""))
 266         repository->fastImport.write("deleteall\n");
 267     else
 268         foreach (QString df, deletedFiles)
 269             repository->fastImport.write("D " + df.toUtf8() + "\n");
 270
 271     // write the file modifications
 272     QHash<QString, FileProperties>::ConstIterator it = modifiedFiles.constBegin();
 273     for ( ; it != modifiedFiles.constEnd(); ++it) {
 274         repository->fastImport.write("M ", 2);
 275         repository->fastImport.write(QByteArray::number(it->mode, 8));
 276         repository->fastImport.write(" :", 2);
 277         repository->fastImport.write(QByteArray::number(it->mark));
 278         repository->fastImport.write(" ", 1);
 279         repository->fastImport.write(it.key().toUtf8());
 280         repository->fastImport.write("\n", 1);
 281     }
 282
 283     repository->fastImport.write("\nprogress Commit #" +
 284                                  QByteArray::number(repository->commitCount) +
 285                                  " branch " + branch +
 286                                  " = SVN r" + QByteArray::number(revnum) + "\n\n");
 287     printf(" %d modifications to \"%s\"",
 288            deletedFiles.count() + modifiedFiles.count(),
 289            qPrintable(repository->name));
 290
 291     while (repository->fastImport.bytesToWrite())
 292         if (!repository->fastImport.waitForBytesWritten(-1))
 293             qFatal("Failed to write to process: %s", qPrintable(repository->fastImport.errorString()));
 294 }