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