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 "options.h"
  20 #include <QTextStream>
  21 #include <QDebug>
  22 #include <QLinkedList>
  23
  24 static const int maxSimultaneousProcesses = 100;
  25
  26 class ProcessCache: QLinkedList<Repository *>
  27 {
  28 public:
  29     void touch(Repository *repo)
  30     {
  31         remove(repo);
  32
  33         // if the cache is too big, remove from the front
  34         while (size() >= maxSimultaneousProcesses)
  35             takeFirst()->closeFastImport();
  36
  37         // append to the end
  38         append(repo);
  39     }
  40
  41     inline void remove(Repository *repo)
  42     {
  43 #if QT_VERSION >= 0x040400
  44         removeOne(repo);
  45 #else
  46         removeAll(repo);
  47 #endif
  48     }
  49 };
  50 static ProcessCache processCache;
  51
  52 Repository::Repository(const Rules::Repository &rule)
  53     : name(rule.name), commitCount(0), outstandingTransactions(0), processHasStarted(false)
  54 {
  55     foreach (Rules::Repository::Branch branchRule, rule.branches) {
  56         Branch branch;
  57         branch.created = 0;     // not created
  58
  59         branches.insert(branchRule.name, branch);
  60     }
  61
  62     // create the default branch
  63     branches["master"].created = 1;
  64
  65     fastImport.setWorkingDirectory(name);
  66 }
  67
  68 Repository::~Repository()
  69 {
  70     Q_ASSERT(outstandingTransactions == 0);
  71     closeFastImport();
  72 }
  73
  74 void Repository::closeFastImport()
  75 {
  76     if (fastImport.state() != QProcess::NotRunning) {
  77         fastImport.write("checkpoint\n");
  78         fastImport.waitForBytesWritten(-1);
  79         fastImport.closeWriteChannel();
  80         if (!fastImport.waitForFinished()) {
  81             fastImport.terminate();
  82             if (!fastImport.waitForFinished(200))
  83                 qWarning() << "git-fast-import for repository" << name << "did not die";
  84         }
  85     }
  86     processHasStarted = false;
  87     processCache.remove(this);
  88 }
  89
  90 void Repository::reloadBranches()
  91 {
  92     QProcess revParse;
  93     revParse.setWorkingDirectory(name);
  94     revParse.start("git", QStringList() << "rev-parse" << "--symbolic" << "--branches");
  95     revParse.waitForFinished(-1);
  96
  97     if (revParse.exitCode() == 0 && revParse.bytesAvailable()) {
  98         while (revParse.canReadLine()) {
  99             QByteArray branchName = revParse.readLine().trimmed();
 100
 101             //qDebug() << "Repo" << name << "reloaded branch" << branchName;
 102             branches[branchName].created = 1;
 103             fastImport.write("reset refs/heads/" + branchName +
 104                              "\nfrom refs/heads/" + branchName + "^0\n\n"
 105                              "progress Branch refs/heads/" + branchName + " reloaded\n");
 106         }
 107     }
 108 }
 109
 110 void Repository::createBranch(const QString &branch, int revnum,
 111                               const QString &branchFrom, int)
 112 {
 113     startFastImport();
 114     if (!branches.contains(branch)) {
 115         qWarning() << branch << "is not a known branch in repository" << name << endl
 116                    << "Going to create it automatically";
 117     }
 118
 119     QByteArray branchRef = branch.toUtf8();
 120     if (!branchRef.startsWith("refs/"))
 121         branchRef.prepend("refs/heads/");
 122
 123     Branch &br = branches[branch];
 124     if (br.created && br.created != revnum) {
 125         QByteArray backupBranch = branchRef + '_' + QByteArray::number(revnum);
 126         qWarning() << branch << "already exists; backing up to" << backupBranch;
 127
 128         fastImport.write("reset " + backupBranch + "\nfrom " + branchRef + "\n\n");
 129     }
 130
 131     // now create the branch
 132     br.created = revnum;
 133     QByteArray branchFromRef = branchFrom.toUtf8();
 134     if (!branchFromRef.startsWith("refs/"))
 135         branchFromRef.prepend("refs/heads/");
 136
 137     if (!branches.contains(branchFrom) || !branches.value(branchFrom).created) {
 138         qCritical() << branch << "in repository" << name
 139                     << "is branching from branch" << branchFrom
 140                     << "but the latter doesn't exist. Can't continue.";
 141         exit(1);
 142     }
 143
 144     fastImport.write("reset " + branchRef + "\nfrom " + branchFromRef + "\n\n"
 145         "progress Branch " + branchRef + " created from " + branchFromRef + "\n\n");
 146 }
 147
 148 Repository::Transaction *Repository::newTransaction(const QString &branch, const QString &svnprefix,
 149                                                     int revnum)
 150 {
 151     startFastImport();
 152     if (!branches.contains(branch)) {
 153         qWarning() << branch << "is not a known branch in repository" << name << endl
 154                    << "Going to create it automatically";
 155     }
 156
 157     Transaction *txn = new Transaction;
 158     txn->repository = this;
 159     txn->branch = branch.toUtf8();
 160     txn->svnprefix = svnprefix.toUtf8();
 161     txn->datetime = 0;
 162     txn->revnum = revnum;
 163
 164     if ((++commitCount % 10000) == 0)
 165         // write everything to disk every 10000 commits
 166         fastImport.write("checkpoint\n");
 167     if (outstandingTransactions++ == 0)
 168         lastmark = 1;           // reset the mark number
 169     return txn;
 170 }
 171
 172 void Repository::startFastImport()
 173 {
 174     if (fastImport.state() == QProcess::NotRunning) {
 175         if (processHasStarted)
 176             qFatal("git-fast-import has been started once and crashed?");
 177         processHasStarted = true;
 178
 179         // start the process
 180         QString outputFile = name;
 181         outputFile.replace('/', '_');
 182         outputFile.prepend("log-");
 183         fastImport.setStandardOutputFile(outputFile, QIODevice::Append);
 184         fastImport.setProcessChannelMode(QProcess::MergedChannels);
 185
 186 #ifndef DRY_RUN
 187         fastImport.start("git", QStringList() << "fast-import");
 188 #else
 189         fastImport.start("/bin/cat", QStringList());
 190 #endif
 191
 192         reloadBranches();
 193     }
 194 }
 195
 196 Repository::Transaction::~Transaction()
 197 {
 198     --repository->outstandingTransactions;
 199 }
 200
 201 void Repository::Transaction::setAuthor(const QByteArray &a)
 202 {
 203     author = a;
 204 }
 205
 206 void Repository::Transaction::setDateTime(uint dt)
 207 {
 208     datetime = dt;
 209 }
 210
 211 void Repository::Transaction::setLog(const QByteArray &l)
 212 {
 213     log = l;
 214 }
 215
 216 void Repository::Transaction::deleteFile(const QString &path)
 217 {
 218     deletedFiles.append(path);
 219 }
 220
 221 QIODevice *Repository::Transaction::addFile(const QString &path, int mode, qint64 length)
 222 {
 223     int mark = ++repository->lastmark;
 224
 225     if (modifiedFiles.capacity() == 0)
 226         modifiedFiles.reserve(2048);
 227     modifiedFiles.append("M ");
 228     modifiedFiles.append(QByteArray::number(mode, 8));
 229     modifiedFiles.append(" :");
 230     modifiedFiles.append(QByteArray::number(mark));
 231     modifiedFiles.append(' ');
 232     modifiedFiles.append(path.toUtf8());
 233     modifiedFiles.append("\n");
 234
 235 #ifndef DRY_RUN
 236     repository->fastImport.write("blob\nmark :");
 237     repository->fastImport.write(QByteArray::number(mark));
 238     repository->fastImport.write("\ndata ");
 239     repository->fastImport.write(QByteArray::number(length));
 240     repository->fastImport.write("\n", 1);
 241 #endif
 242
 243     return &repository->fastImport;
 244 }
 245
 246 void Repository::Transaction::commit()
 247 {
 248     processCache.touch(repository);
 249
 250     // create the commit message
 251     QByteArray message = log;
 252     if (!message.endsWith('\n'))
 253         message += '\n';
 254     if (Options::globalOptions->switches.value("metadata", true))
 255         message += "\nsvn path=" + svnprefix + "; revision=" + QByteArray::number(revnum) + "\n";
 256
 257     {
 258         QByteArray branchRef = branch;
 259         if (!branchRef.startsWith("refs/"))
 260             branchRef.prepend("refs/heads/");
 261
 262         QTextStream s(&repository->fastImport);
 263         s << "commit " << branchRef << endl;
 264         s << "committer " << QString::fromUtf8(author) << ' ' << datetime << " -0000" << endl;
 265
 266         Branch &br = repository->branches[branch];
 267         if (!br.created) {
 268             qWarning() << "Branch" << branch << "in repository" << repository->name << "doesn't exist at revision"
 269                        << revnum << "-- did you resume from the wrong revision?";
 270             br.created = revnum;
 271         }
 272
 273         s << "data " << message.length() << endl;
 274     }
 275
 276     repository->fastImport.write(message);
 277     repository->fastImport.putChar('\n');
 278
 279     // write the file deletions
 280     if (deletedFiles.contains(""))
 281         repository->fastImport.write("deleteall\n");
 282     else
 283         foreach (QString df, deletedFiles)
 284             repository->fastImport.write("D " + df.toUtf8() + "\n");
 285
 286     // write the file modifications
 287     repository->fastImport.write(modifiedFiles);
 288
 289     repository->fastImport.write("\nprogress Commit #" +
 290                                  QByteArray::number(repository->commitCount) +
 291                                  " branch " + branch +
 292                                  " = SVN r" + QByteArray::number(revnum) + "\n\n");
 293     printf(" %d modifications to \"%s\"",
 294            deletedFiles.count() + modifiedFiles.count(),
 295            qPrintable(repository->name));
 296
 297     while (repository->fastImport.bytesToWrite())
 298         if (!repository->fastImport.waitForBytesWritten(-1))
 299             qFatal("Failed to write to process: %s", qPrintable(repository->fastImport.errorString()));
 300 }