From 31ef8fa6abc2ea23c6f0a996b36494d88aafb0b5 Mon Sep 17 00:00:00 2001 From: mae Date: Fri, 29 Apr 2011 11:44:43 +0200 Subject: Reduce open and stat system calls for QSettings The patch moves the global static QSettings object from QLibrary to QCoreApplication and reduces a few stat and open calls. Without the patch, a large Trolltech.conf was pushed out of the unused settings cache during startup, meaning Trolltech.conf was parsed more than once. Reviewed-by: Liang Qi --- src/corelib/io/qsettings.cpp | 29 +++++------------------------ src/corelib/kernel/qcoreapplication.cpp | 12 ++++++++++++ src/corelib/kernel/qcoreapplication_p.h | 2 ++ src/corelib/plugin/qlibrary.cpp | 13 ++----------- src/gui/kernel/qcursor_x11.cpp | 3 +++ 5 files changed, 24 insertions(+), 35 deletions(-) diff --git a/src/corelib/io/qsettings.cpp b/src/corelib/io/qsettings.cpp index b084ca5..f43fb31 100644 --- a/src/corelib/io/qsettings.cpp +++ b/src/corelib/io/qsettings.cpp @@ -981,23 +981,6 @@ QStringList QSettingsPrivate::splitArgs(const QString &s, int idx) // ************************************************************************ // QConfFileSettingsPrivate -/* - If we don't have the permission to read the file, returns false. - If the file doesn't exist, returns true. -*/ -static bool checkAccess(const QString &name) -{ - QFileInfo fileInfo(name); - - if (fileInfo.exists()) { - QFile file(name); - // if the file exists but we can't open it, report an error - return file.open(QFile::ReadOnly); - } else { - return true; - } -} - void QConfFileSettingsPrivate::initFormat() { extension = (format == QSettings::NativeFormat) ? QLatin1String(".conf") : QLatin1String(".ini"); @@ -1026,18 +1009,13 @@ void QConfFileSettingsPrivate::initFormat() void QConfFileSettingsPrivate::initAccess() { - bool readAccess = false; if (confFiles[spec]) { - readAccess = checkAccess(confFiles[spec]->name); if (format > QSettings::IniFormat) { if (!readFunc) - readAccess = false; + setStatus(QSettings::AccessError); } } - if (!readAccess) - setStatus(QSettings::AccessError); - sync(); // loads the files the first time } @@ -1432,7 +1410,7 @@ void QConfFileSettingsPrivate::syncConfFile(int confFileNo) We can often optimize the read-only case, if the file on disk hasn't changed. */ - if (readOnly) { + if (readOnly && confFile->size > 0) { QFileInfo fileInfo(confFile->name); if (confFile->size == fileInfo.size() && confFile->timeStamp == fileInfo.lastModified()) return; @@ -1455,6 +1433,9 @@ void QConfFileSettingsPrivate::syncConfFile(int confFileNo) if (!file.isOpen()) file.open(QFile::ReadOnly); + if (!createFile && !file.isOpen()) + setStatus(QSettings::AccessError); + #ifdef Q_OS_WIN HANDLE readSemaphore = 0; HANDLE writeSemaphore = 0; diff --git a/src/corelib/kernel/qcoreapplication.cpp b/src/corelib/kernel/qcoreapplication.cpp index be86c58..df8bc59 100644 --- a/src/corelib/kernel/qcoreapplication.cpp +++ b/src/corelib/kernel/qcoreapplication.cpp @@ -270,6 +270,8 @@ bool QCoreApplicationPrivate::is_app_closing = false; Q_CORE_EXPORT bool qt_locale_initialized = false; +QSettings *QCoreApplicationPrivate::trolltechConf = 0; + Q_CORE_EXPORT uint qGlobalPostedEventsCount() { QThreadData *currentThreadData = QThreadData::current(); @@ -371,6 +373,9 @@ QCoreApplicationPrivate::~QCoreApplicationPrivate() threadData->postEventList.recursion = 0; threadData->quitNow = false; } + + delete trolltechConf; + trolltechConf = 0; } void QCoreApplicationPrivate::createEventDispatcher() @@ -688,6 +693,13 @@ void QCoreApplication::init() } #endif + + /* + Create an instance of Trolltech.conf. This ensures that the settings will not + be thrown out of QSetting's cache for unused settings. + */ + d->trolltechConf = new QSettings(QSettings::UserScope, QLatin1String("Trolltech")); + qt_startup_hook(); } diff --git a/src/corelib/kernel/qcoreapplication_p.h b/src/corelib/kernel/qcoreapplication_p.h index add2a35..0557f83 100644 --- a/src/corelib/kernel/qcoreapplication_p.h +++ b/src/corelib/kernel/qcoreapplication_p.h @@ -55,6 +55,7 @@ #include "QtCore/qcoreapplication.h" #include "QtCore/qtranslator.h" +#include "QtCore/qsettings.h" #include "private/qobject_p.h" #ifdef Q_OS_SYMBIAN @@ -139,6 +140,7 @@ public: #if defined(QT3_SUPPORT) static bool useQt3Support; #endif + static QSettings *trolltechConf; }; QT_END_NAMESPACE diff --git a/src/corelib/plugin/qlibrary.cpp b/src/corelib/plugin/qlibrary.cpp index 80e927b..6f3ee1c 100644 --- a/src/corelib/plugin/qlibrary.cpp +++ b/src/corelib/plugin/qlibrary.cpp @@ -52,6 +52,7 @@ #include #include #include +#include #ifdef Q_OS_MAC # include #endif @@ -408,12 +409,6 @@ static bool qt_unix_query(const QString &library, uint *version, bool *debug, QB typedef QMap LibraryMap; struct LibraryData { - LibraryData() : settings(0) { } - ~LibraryData() { - delete settings; - } - - QSettings *settings; LibraryMap libraryMap; QSet loadedLibs; }; @@ -711,11 +706,7 @@ bool QLibraryPrivate::isPlugin(QSettings *settings) QStringList reg; #ifndef QT_NO_SETTINGS if (!settings) { - settings = libraryData()->settings; - if (!settings) { - settings = new QSettings(QSettings::UserScope, QLatin1String("Trolltech")); - libraryData()->settings = settings; - } + settings = QCoreApplicationPrivate::trolltechConf; } reg = settings->value(regkey).toStringList(); #endif diff --git a/src/gui/kernel/qcursor_x11.cpp b/src/gui/kernel/qcursor_x11.cpp index d0ed98e..0bc7250 100644 --- a/src/gui/kernel/qcursor_x11.cpp +++ b/src/gui/kernel/qcursor_x11.cpp @@ -55,6 +55,9 @@ #endif // QT_NO_XCURSOR #ifndef QT_NO_XFIXES +#ifndef Status +#define Status int +#endif # include #endif // QT_NO_XFIXES -- cgit v0.12