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