filemanager.cpp Example File

torrent/filemanager.cpp
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#include "filemanager.h" #include "metainfo.h" #include <QByteArray> #include <QDir> #include <QFile> #include <QTimer> #include <QTimerEvent> #include <QCryptographicHash> FileManager::FileManager(QObject *parent) : QThread(parent) { quit = false; totalLength = 0; readId = 0; startVerification = false; wokeUp = false; newFile = false; numPieces = 0; verifiedPieces.fill(false); } FileManager::~FileManager() { quit = true; cond.wakeOne(); wait(); foreach (QFile *file, files) { file->close(); delete file; } } int FileManager::read(int pieceIndex, int offset, int length) { ReadRequest request; request.pieceIndex = pieceIndex; request.offset = offset; request.length = length; QMutexLocker locker(&mutex); request.id = readId++; readRequests << request; if (!wokeUp) { wokeUp = true; QMetaObject::invokeMethod(this, "wakeUp", Qt::QueuedConnection); } return request.id; } void FileManager::write(int pieceIndex, int offset, const QByteArray &data) { WriteRequest request; request.pieceIndex = pieceIndex; request.offset = offset; request.data = data; QMutexLocker locker(&mutex); writeRequests << request; if (!wokeUp) { wokeUp = true; QMetaObject::invokeMethod(this, "wakeUp", Qt::QueuedConnection); } } void FileManager::verifyPiece(int pieceIndex) { QMutexLocker locker(&mutex); pendingVerificationRequests << pieceIndex; startVerification = true; if (!wokeUp) { wokeUp = true; QMetaObject::invokeMethod(this, "wakeUp", Qt::QueuedConnection); } } int FileManager::pieceLengthAt(int pieceIndex) const { QMutexLocker locker(&mutex); return (sha1s.size() == pieceIndex + 1) ? (totalLength % pieceLength) : pieceLength; } QBitArray FileManager::completedPieces() const { QMutexLocker locker(&mutex); return verifiedPieces; } void FileManager::setCompletedPieces(const QBitArray &pieces) { QMutexLocker locker(&mutex); verifiedPieces = pieces; } QString FileManager::errorString() const { return errString; } void FileManager::run() { if (!generateFiles()) return; do { { // Go to sleep if there's nothing to do. QMutexLocker locker(&mutex); if (!quit && readRequests.isEmpty() && writeRequests.isEmpty() && !startVerification) cond.wait(&mutex); } // Read pending read requests mutex.lock(); QList<ReadRequest> newReadRequests = readRequests; readRequests.clear(); mutex.unlock(); while (!newReadRequests.isEmpty()) { ReadRequest request = newReadRequests.takeFirst(); QByteArray block = readBlock(request.pieceIndex, request.offset, request.length); emit dataRead(request.id, request.pieceIndex, request.offset, block); } // Write pending write requests mutex.lock(); QList<WriteRequest> newWriteRequests = writeRequests; writeRequests.clear(); while (!quit && !newWriteRequests.isEmpty()) { WriteRequest request = newWriteRequests.takeFirst(); writeBlock(request.pieceIndex, request.offset, request.data); } // Process pending verification requests if (startVerification) { newPendingVerificationRequests = pendingVerificationRequests; pendingVerificationRequests.clear(); verifyFileContents(); startVerification = false; } mutex.unlock(); newPendingVerificationRequests.clear(); } while (!quit); // Write pending write requests mutex.lock(); QList<WriteRequest> newWriteRequests = writeRequests; writeRequests.clear(); mutex.unlock(); while (!newWriteRequests.isEmpty()) { WriteRequest request = newWriteRequests.takeFirst(); writeBlock(request.pieceIndex, request.offset, request.data); } } void FileManager::startDataVerification() { QMutexLocker locker(&mutex); startVerification = true; cond.wakeOne(); } bool FileManager::generateFiles() { numPieces = -1; // Set up the thread local data if (metaInfo.fileForm() == MetaInfo::SingleFileForm) { QMutexLocker locker(&mutex); MetaInfoSingleFile singleFile = metaInfo.singleFile(); QString prefix; if (!destinationPath.isEmpty()) { prefix = destinationPath; if (!prefix.endsWith('/')) prefix += '/'; QDir dir; if (!dir.mkpath(prefix)) { errString = tr("Failed to create directory %1").arg(prefix); emit error(); return false; } } QFile *file = new QFile(prefix + singleFile.name); if (!file->open(QFile::ReadWrite)) { errString = tr("Failed to open/create file %1: %2") .arg(file->fileName()).arg(file->errorString()); emit error(); delete file; return false; } if (file->size() != singleFile.length) { newFile = true; if (!file->resize(singleFile.length)) { errString = tr("Failed to resize file %1: %2") .arg(file->fileName()).arg(file->errorString()); delete file; emit error(); return false; } } fileSizes << file->size(); files << file; file->close(); pieceLength = singleFile.pieceLength; totalLength = singleFile.length; sha1s = singleFile.sha1Sums; } else { QMutexLocker locker(&mutex); QDir dir; QString prefix; if (!destinationPath.isEmpty()) { prefix = destinationPath; if (!prefix.endsWith('/')) prefix += '/'; } if (!metaInfo.name().isEmpty()) { prefix += metaInfo.name(); if (!prefix.endsWith('/')) prefix += '/'; } if (!dir.mkpath(prefix)) { errString = tr("Failed to create directory %1").arg(prefix); emit error(); return false; } foreach (const MetaInfoMultiFile &entry, metaInfo.multiFiles()) { QString filePath = QFileInfo(prefix + entry.path).path(); if (!QFile::exists(filePath)) { if (!dir.mkpath(filePath)) { errString = tr("Failed to create directory %1").arg(filePath); emit error(); return false; } } QFile *file = new QFile(prefix + entry.path); if (!file->open(QFile::ReadWrite)) { errString = tr("Failed to open/create file %1: %2") .arg(file->fileName()).arg(file->errorString()); emit error(); delete file; return false; } if (file->size() != entry.length) { newFile = true; if (!file->resize(entry.length)) { errString = tr("Failed to resize file %1: %2") .arg(file->fileName()).arg(file->errorString()); emit error(); delete file; return false; } } fileSizes << file->size(); files << file; file->close(); totalLength += entry.length; } sha1s = metaInfo.sha1Sums(); pieceLength = metaInfo.pieceLength(); } numPieces = sha1s.size(); return true; } QByteArray FileManager::readBlock(int pieceIndex, int offset, int length) { QByteArray block; qint64 startReadIndex = (quint64(pieceIndex) * pieceLength) + offset; qint64 currentIndex = 0; for (int i = 0; !quit && i < files.size() && length > 0; ++i) { QFile *file = files[i]; qint64 currentFileSize = fileSizes.at(i); if ((currentIndex + currentFileSize) > startReadIndex) { if (!file->isOpen()) { if (!file->open(QFile::ReadWrite)) { errString = tr("Failed to read from file %1: %2") .arg(file->fileName()).arg(file->errorString()); emit error(); break; } } file->seek(startReadIndex - currentIndex); QByteArray chunk = file->read(qMin<qint64>(length, currentFileSize - file->pos())); file->close(); block += chunk; length -= chunk.size(); startReadIndex += chunk.size(); if (length < 0) { errString = tr("Failed to read from file %1 (read %3 bytes): %2") .arg(file->fileName()).arg(file->errorString()).arg(length); emit error(); break; } } currentIndex += currentFileSize; } return block; } bool FileManager::writeBlock(int pieceIndex, int offset, const QByteArray &data) { qint64 startWriteIndex = (qint64(pieceIndex) * pieceLength) + offset; qint64 currentIndex = 0; int bytesToWrite = data.size(); int written = 0; for (int i = 0; !quit && i < files.size(); ++i) { QFile *file = files[i]; qint64 currentFileSize = fileSizes.at(i); if ((currentIndex + currentFileSize) > startWriteIndex) { if (!file->isOpen()) { if (!file->open(QFile::ReadWrite)) { errString = tr("Failed to write to file %1: %2") .arg(file->fileName()).arg(file->errorString()); emit error(); break; } } file->seek(startWriteIndex - currentIndex); qint64 bytesWritten = file->write(data.constData() + written, qMin<qint64>(bytesToWrite, currentFileSize - file->pos())); file->close(); if (bytesWritten <= 0) { errString = tr("Failed to write to file %1: %2") .arg(file->fileName()).arg(file->errorString()); emit error(); return false; } written += bytesWritten; startWriteIndex += bytesWritten; bytesToWrite -= bytesWritten; if (bytesToWrite == 0) break; } currentIndex += currentFileSize; } return true; } void FileManager::verifyFileContents() { // Verify all pieces the first time if (newPendingVerificationRequests.isEmpty()) { if (verifiedPieces.count(true) == 0) { verifiedPieces.resize(sha1s.size()); int oldPercent = 0; if (!newFile) { int numPieces = sha1s.size(); for (int index = 0; index < numPieces; ++index) { verifySinglePiece(index); int percent = ((index + 1) * 100) / numPieces; if (oldPercent != percent) { emit verificationProgress(percent); oldPercent = percent; } } } } emit verificationDone(); return; } // Verify all pending pieces foreach (int index, newPendingVerificationRequests) emit pieceVerified(index, verifySinglePiece(index)); } bool FileManager::verifySinglePiece(int pieceIndex) { QByteArray block = readBlock(pieceIndex, 0, pieceLength); QByteArray sha1Sum = QCryptographicHash::hash(block, QCryptographicHash::Sha1); if (sha1Sum != sha1s.at(pieceIndex)) return false; verifiedPieces.setBit(pieceIndex); return true; } void FileManager::wakeUp() { QMutexLocker locker(&mutex); wokeUp = false; cond.wakeOne(); }

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