From 9a89f573e03e4042d3c4c91f8183ae39e55667fb Mon Sep 17 00:00:00 2001 From: Oswald Buddenhagen Date: Wed, 30 Mar 2011 12:06:05 +0200 Subject: [PATCH] add fileutils: classes for error-checked reading and writing of files the internal use of SaveFile ensures that we don't leave truncated pre-existing files behind if the disk is full or something else bad happens. Task-number: QTCREATORBUG-1619 --- src/libs/utils/fileutils.cpp | 247 +++++++++++++++++++++++++++++++++++ src/libs/utils/fileutils.h | 133 +++++++++++++++++++ src/libs/utils/utils-lib.pri | 2 + 3 files changed, 382 insertions(+) create mode 100644 src/libs/utils/fileutils.cpp create mode 100644 src/libs/utils/fileutils.h diff --git a/src/libs/utils/fileutils.cpp b/src/libs/utils/fileutils.cpp new file mode 100644 index 00000000000..071994eddd6 --- /dev/null +++ b/src/libs/utils/fileutils.cpp @@ -0,0 +1,247 @@ +/************************************************************************** +** +** This file is part of Qt Creator +** +** Copyright (c) 2011 Nokia Corporation and/or its subsidiary(-ies). +** +** Contact: Nokia Corporation (info@qt.nokia.com) +** +** +** GNU Lesser General Public License Usage +** +** This file may be used under the terms of the GNU Lesser General Public +** License version 2.1 as published by the Free Software Foundation and +** appearing in the file LICENSE.LGPL included in the packaging of this file. +** Please review the following information to ensure the GNU Lesser General +** Public License version 2.1 requirements will be met: +** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** Other Usage +** +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +**************************************************************************/ + +#include "fileutils.h" +#include "savefile.h" + +#include "qtcassert.h" + +#include +#include +#include +#include +#include +#include +#include + +namespace Utils { + +QByteArray FileReader::fetchQrc(const QString &fileName) +{ + QTC_ASSERT(fileName.startsWith(QLatin1Char(':')), return QByteArray()) + QFile file(fileName); + bool ok = file.open(QIODevice::ReadOnly); + QTC_ASSERT(ok, qWarning() << fileName << "not there!"; return QByteArray()) + return file.readAll(); +} + +bool FileReader::fetch(const QString &fileName, QIODevice::OpenMode mode) +{ + QTC_ASSERT(!(mode & ~(QIODevice::ReadOnly | QIODevice::Text)), return false) + + QFile file(fileName); + if (!file.open(QIODevice::ReadOnly | mode)) { + m_errorString = tr("Cannot open %1 for reading: %2").arg( + QDir::toNativeSeparators(fileName), file.errorString()); + return false; + } + m_data = file.readAll(); + if (file.error() != QFile::NoError) { + m_errorString = tr("Cannot read %1: %2").arg( + QDir::toNativeSeparators(fileName), file.errorString()); + return false; + } + return true; +} + +bool FileReader::fetch(const QString &fileName, QIODevice::OpenMode mode, QString *errorString) +{ + if (fetch(fileName, mode)) + return true; + if (errorString) + *errorString = m_errorString; + return false; +} + +bool FileReader::fetch(const QString &fileName, QIODevice::OpenMode mode, QWidget *parent) +{ + if (fetch(fileName, mode)) + return true; + if (parent) + QMessageBox::critical(parent, tr("File Error"), m_errorString); + return false; +} + + +FileSaverBase::FileSaverBase() + : m_hasError(false) +{ +} + +FileSaverBase::~FileSaverBase() +{ + delete m_file; +} + +bool FileSaverBase::finalize() +{ + m_file->close(); + setResult(m_file->error() == QFile::NoError); + // We delete the object, so it is really closed even if it is a QTemporaryFile. + delete m_file; + m_file = 0; + return !m_hasError; +} + +bool FileSaverBase::finalize(QString *errStr) +{ + if (finalize()) + return true; + if (errStr) + *errStr = errorString(); + return false; +} + +bool FileSaverBase::finalize(QWidget *parent) +{ + if (finalize()) + return true; + QMessageBox::critical(parent, tr("File Error"), errorString()); + return false; +} + +bool FileSaverBase::write(const char *data, int len) +{ + if (m_hasError) + return false; + return setResult(m_file->write(data, len) == len); +} + +bool FileSaverBase::write(const QByteArray &bytes) +{ + if (m_hasError) + return false; + return setResult(m_file->write(bytes) == bytes.count()); +} + +bool FileSaverBase::setResult(bool ok) +{ + if (!ok && !m_hasError) { + m_errorString = tr("Cannot write file %1. Disk full?").arg( + QDir::toNativeSeparators(m_fileName)); + m_hasError = true; + } + return ok; +} + +bool FileSaverBase::setResult(QTextStream *stream) +{ +#if QT_VERSION >= QT_VERSION_CHECK(4, 8, 0) + stream->flush(); + return setResult(stream->status() == QTextStream::Ok); +#else + Q_UNUSED(stream) + return true; +#endif +} + +bool FileSaverBase::setResult(QDataStream *stream) +{ +#if QT_VERSION >= QT_VERSION_CHECK(4, 8, 0) + stream->flush(); + return setResult(stream->status() == QTextStream::Ok); +#else + Q_UNUSED(stream) + return true; +#endif +} + +bool FileSaverBase::setResult(QXmlStreamWriter *stream) +{ +#if QT_VERSION >= QT_VERSION_CHECK(4, 8, 0) + return setResult(!stream->hasError()); +#else + Q_UNUSED(stream) + return true; +#endif +} + + +FileSaver::FileSaver(const QString &filename, QIODevice::OpenMode mode) +{ + m_fileName = filename; + if (mode & (QIODevice::ReadOnly | QIODevice::Append)) { + m_file = new QFile(filename); + m_isSafe = false; + } else { + m_file = new SaveFile(filename); + m_isSafe = true; + } + if (!m_file->open(QIODevice::WriteOnly | mode)) { + QString err = QFile::exists(filename) ? + tr("Cannot overwrite file %1: %2") : tr("Cannot create file %1: %2"); + m_errorString = err.arg(QDir::toNativeSeparators(filename), m_file->errorString()); + m_hasError = true; + } +} + +bool FileSaver::finalize() +{ + if (!m_isSafe) + return FileSaverBase::finalize(); + + SaveFile *sf = static_cast(m_file); + if (m_hasError) + sf->rollback(); + else + setResult(sf->commit()); + delete sf; + m_file = 0; + return !m_hasError; +} + +TempFileSaver::TempFileSaver(const QString &templ) + : m_autoRemove(true) +{ + QTemporaryFile *tempFile = new QTemporaryFile(); + if (!templ.isEmpty()) + tempFile->setFileTemplate(templ); + tempFile->setAutoRemove(false); + if (!tempFile->open()) { + m_errorString = tr("Cannot create temporary file in %1: %2").arg( + QDir::toNativeSeparators(QFileInfo(tempFile->fileTemplate()).absolutePath()), + tempFile->errorString()); + m_hasError = true; + } + m_file = tempFile; + m_fileName = tempFile->fileName(); +} + +TempFileSaver::~TempFileSaver() +{ + delete m_file; + m_file = 0; + if (m_autoRemove) + QFile::remove(m_fileName); +} + +} // namespace Utils diff --git a/src/libs/utils/fileutils.h b/src/libs/utils/fileutils.h new file mode 100644 index 00000000000..a4efecab420 --- /dev/null +++ b/src/libs/utils/fileutils.h @@ -0,0 +1,133 @@ +/************************************************************************** +** +** This file is part of Qt Creator +** +** Copyright (c) 2011 Nokia Corporation and/or its subsidiary(-ies). +** +** Contact: Nokia Corporation (info@qt.nokia.com) +** +** +** GNU Lesser General Public License Usage +** +** This file may be used under the terms of the GNU Lesser General Public +** License version 2.1 as published by the Free Software Foundation and +** appearing in the file LICENSE.LGPL included in the packaging of this file. +** Please review the following information to ensure the GNU Lesser General +** Public License version 2.1 requirements will be met: +** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** Other Usage +** +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +**************************************************************************/ + +#ifndef FILEUTILS_H +#define FILEUTILS_H + +#include "utils_global.h" + +#include +#include + +QT_BEGIN_NAMESPACE +class QFile; +class QTemporaryFile; +class QWidget; +class QTextStream; +class QDataStream; +class QXmlStreamWriter; +QT_END_NAMESPACE + +namespace Utils { + +class QTCREATOR_UTILS_EXPORT FileReader +{ + Q_DECLARE_TR_FUNCTIONS(FileUtils) // sic! +public: + static QByteArray fetchQrc(const QString &fileName); // Only for internal resources + bool fetch(const QString &fileName, QIODevice::OpenMode mode = QIODevice::NotOpen); // QIODevice::ReadOnly is implicit + bool fetch(const QString &fileName, QIODevice::OpenMode mode, QString *errorString); + bool fetch(const QString &fileName, QString *errorString) + { return fetch(fileName, QIODevice::NotOpen, errorString); } + bool fetch(const QString &fileName, QIODevice::OpenMode mode, QWidget *parent); + bool fetch(const QString &fileName, QWidget *parent) + { return fetch(fileName, QIODevice::NotOpen, parent); } + const QByteArray &data() const { return m_data; } + const QString &errorString() const { return m_errorString; } +private: + QByteArray m_data; + QString m_errorString; +}; + +class QTCREATOR_UTILS_EXPORT FileSaverBase +{ + Q_DECLARE_TR_FUNCTIONS(FileUtils) // sic! +public: + FileSaverBase(); + virtual ~FileSaverBase(); + + QString fileName() const { return m_fileName; } + bool hasError() const { return m_hasError; } + QString errorString() const { return m_errorString; } + virtual bool finalize(); + bool finalize(QString *errStr); + bool finalize(QWidget *parent); + + bool write(const char *data, int len); + bool write(const QByteArray &bytes); + bool setResult(QTextStream *stream); + bool setResult(QDataStream *stream); + bool setResult(QXmlStreamWriter *stream); + bool setResult(bool ok); + +protected: + QFile *m_file; + QString m_fileName; + QString m_errorString; + bool m_hasError; + +private: + Q_DISABLE_COPY(FileSaverBase) +}; + +class QTCREATOR_UTILS_EXPORT FileSaver : public FileSaverBase +{ +public: + explicit FileSaver(const QString &filename, QIODevice::OpenMode mode = QIODevice::NotOpen); // QIODevice::WriteOnly is implicit + + virtual bool finalize(); + using FileSaverBase::finalize; + QFile *file() { return m_file; } + +private: + Q_DISABLE_COPY(FileSaver) + bool m_isSafe; +}; + +class QTCREATOR_UTILS_EXPORT TempFileSaver : public FileSaverBase +{ +public: + explicit TempFileSaver(const QString &templ = QString()); + ~TempFileSaver(); + + QTemporaryFile *file() { return reinterpret_cast(m_file); } + + void setAutoRemove(bool on) { m_autoRemove = on; } + +private: + Q_DISABLE_COPY(TempFileSaver) + bool m_autoRemove; +}; + +} + +#endif // FILEUTILS_H diff --git a/src/libs/utils/utils-lib.pri b/src/libs/utils/utils-lib.pri index 9f42979a13c..616a344a10d 100644 --- a/src/libs/utils/utils-lib.pri +++ b/src/libs/utils/utils-lib.pri @@ -34,6 +34,7 @@ SOURCES += $$PWD/environment.cpp \ $$PWD/submiteditorwidget.cpp \ $$PWD/synchronousprocess.cpp \ $$PWD/savefile.cpp \ + $$PWD/fileutils.cpp \ $$PWD/submitfieldwidget.cpp \ $$PWD/consoleprocess.cpp \ $$PWD/uncommentselection.cpp \ @@ -124,6 +125,7 @@ HEADERS += $$PWD/environment.h \ $$PWD/consoleprocess.h \ $$PWD/synchronousprocess.h \ $$PWD/savefile.h \ + $$PWD/fileutils.h \ $$PWD/submitfieldwidget.h \ $$PWD/uncommentselection.h \ $$PWD/parameteraction.h \