LP-419 add settings utilities

provides utilities to initialize, load and merge factory defaults settings

ground/gcs/src/libs/utils/settingsutils.cpp

@@ -0,0 +1,222 @@
+/**
+ ******************************************************************************
+ *
+ * @file       settingsutils.cpp
+ * @author     The LibrePilot Project, http://www.librepilot.org Copyright (C) 2017.
+ * @brief      Settings utilities
+ *
+ * @see        The GNU Public License (GPL) Version 3
+ *
+ *****************************************************************************/
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "settingsutils.h"
+
+#include "pathutils.h"
+#include "xmlconfig.h"
+
+#include <QFileInfo>
+#include <QDir>
+#include <QDebug>
+#include <QSettings>
+
+namespace Utils {
+static const QString DEFAULT_CONFIG_DIRNAME  = "configurations";
+static const QString DEFAULT_CONFIG_FILENAME = "default.xml";
+
+const QLatin1String CONFIG_OPTION("-D");
+
+// list of read only QSettings objects containing factory defaults
+QList<QSettings const *> factorySettingsList;
+
+// helper class to manage a simple registry
+class QTCREATOR_UTILS_EXPORT Registry {
+public:
+    Registry(QSettings &settings) : settings(settings)
+    {
+        settings.beginGroup("registry");
+        registry = settings.childKeys();
+        settings.endGroup();
+        // qDebug() << "read registry: " << settings.group() << registry;
+    }
+
+    void save() const
+    {
+        // qDebug() << "saving registry: " << settings.group() << registry;
+        settings.beginGroup("registry");
+        settings.remove("");
+        foreach(QString entry, registry) {
+            settings.setValue(key(entry), 1);
+        }
+        settings.endGroup();
+    }
+
+    bool contains(QString &entry) const
+    {
+        return registry.contains(key(entry));
+    }
+
+    void add(QString &entry)
+    {
+        registry.append(key(entry));
+    }
+
+private:
+    QSettings &settings;
+    QStringList registry;
+
+    QString key(QString &entry) const
+    {
+        return entry;
+    }
+};
+
+QString checkFile(QString fileName)
+{
+    if (!fileName.isEmpty()) {
+        QFileInfo fi(fileName);
+        if (fi.isRelative()) {
+            // file name has a relative path
+            QDir directory(Utils::GetDataPath() + QString("configurations"));
+            fileName = directory.absoluteFilePath(fileName);
+        }
+        if (!QFile::exists(fileName)) {
+            qWarning() << "Configuration file" << fileName << "does not exist.";
+            fileName = "";
+        }
+    }
+    return fileName;
+}
+
+template<typename Func>
+void applyToFactorySettings(Func func)
+{
+    foreach(QSettings const *settings, factorySettingsList) {
+        func(*settings);
+    }
+}
+
+void copySettings(const QSettings &from, QSettings &to)
+{
+    foreach(QString key, from.allKeys()) {
+        if (!to.contains(key)) {
+            // qDebug() << "+++" << key <<  from.value(key);
+            to.setValue(key, from.value(key));
+        } else if (from.value(key) != to.value(key)) {
+            // qDebug() << ">>>" << key <<  from.value(key) << to.value(key);
+            to.setValue(key, from.value(key));
+        }
+    }
+}
+
+void mergeSettings(const QSettings &from, QSettings &to)
+{
+    const_cast<QSettings &>(from).beginGroup(to.group());
+
+    // registry of all groups ever seen
+    // used to avoid re-adding a group that was deleted by the user
+    Registry registry(to);
+
+    // iterate over factory defaults groups
+    foreach(QString group, from.childGroups()) {
+        const_cast<QSettings &>(from).beginGroup(group);
+        to.beginGroup(group);
+        if (!registry.contains(group)) {
+            // registry keeps growing...
+            registry.add(group);
+            if (to.allKeys().count() <= 0) {
+                // found new group, copy it to the destination
+                copySettings(from, to);
+            }
+        }
+        to.endGroup();
+        const_cast<QSettings &>(from).endGroup();
+    }
+
+    registry.save();
+
+    const_cast<QSettings &>(from).endGroup();
+}
+
+void initSettings(const QString &factoryDefaultsFileName)
+{
+    QSettings::setDefaultFormat(XmlConfig::XmlFormat);
+
+    QDir directory(Utils::GetDataPath() + DEFAULT_CONFIG_DIRNAME);
+
+    // check if command line option -config-file contains a file name
+    QString fileName = checkFile(factoryDefaultsFileName);
+
+    if (fileName.isEmpty()) {
+        // check default file
+        qDebug() << "Looking for factory defaults configuration files in" << directory.absolutePath();
+        fileName = checkFile(directory.absoluteFilePath(DEFAULT_CONFIG_FILENAME));
+    }
+
+    if (fileName.isEmpty()) {
+        // TODO should we exit violently?
+        qCritical() << "No default configuration file found!";
+        return;
+    }
+
+    QStringList files;
+
+    // defaults
+    files << fileName;
+
+    foreach(QString file, files) {
+        file = checkFile(file);
+
+        QSettings const *settings = new QSettings(file, XmlConfig::XmlFormat);
+        qDebug() << "Loaded factory defaults" << file;
+
+        factorySettingsList.append(settings);
+    }
+}
+
+void overrideSettings(QSettings &settings, int argc, char * *argv)
+{
+    // Options like -D My/setting=test
+    QRegExp rx("([^=]+)=(.*)");
+
+    for (int i = 0; i < argc; ++i) {
+        if (CONFIG_OPTION == QString(argv[i])) {
+            if (rx.indexIn(argv[++i]) > -1) {
+                QString key   = rx.cap(1);
+                QString value = rx.cap(2);
+                qDebug() << "User setting" << key << "set to value" << value;
+                settings.setValue(key, value);
+            }
+        }
+    }
+}
+
+void resetToFactoryDefaults(QSettings &toSettings)
+{
+    toSettings.clear();
+    applyToFactorySettings(
+        [&](const QSettings &fromSettings) { copySettings(fromSettings, toSettings); }
+        );
+}
+
+void mergeFactoryDefaults(QSettings &toSettings)
+{
+    applyToFactorySettings(
+        [&](const QSettings &fromSettings) { mergeSettings(fromSettings, toSettings); }
+        );
+}
+}

ground/gcs/src/libs/utils/settingsutils.h

@@ -0,0 +1,44 @@
+/**
+ ******************************************************************************
+ *
+ * @file       settingsutils.h
+ * @author     The LibrePilot Project, http://www.librepilot.org Copyright (C) 2017.
+ *             Parts by Nokia Corporation (qt-info@nokia.com) Copyright (C) 2009.
+ * @brief
+ * @see        The GNU Public License (GPL) Version 3
+ * @defgroup
+ * @{
+ *
+ *****************************************************************************/
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef SETTINGS_UTILS_H
+#define SETTINGS_UTILS_H
+
+#include "utils_global.h"
+
+#include <QString>
+#include <QSettings>
+
+namespace Utils {
+QTCREATOR_UTILS_EXPORT void initSettings(const QString &factoryDefaultsFileName);
+QTCREATOR_UTILS_EXPORT void overrideSettings(QSettings &settings, int argc, char * *argv);
+QTCREATOR_UTILS_EXPORT void resetToFactoryDefaults(QSettings &settings);
+QTCREATOR_UTILS_EXPORT void mergeFactoryDefaults(QSettings &settings);
+}
+
+#endif /* SETTINGS_UTILS_H */

ground/gcs/src/libs/utils/utils.pro

@@ -29,6 +29,7 @@ SOURCES += \
     detailswidget.cpp \
     coordinateconversions.cpp \
     pathutils.cpp \
+    settingsutils.cpp \
     worldmagmodel.cpp \
     homelocationutil.cpp \
     mytabbedstackwidget.cpp \
@@ -74,6 +75,7 @@ HEADERS += \
     detailswidget.h \
     coordinateconversions.h \
     pathutils.h \
+    settingsutils.h \
     worldmagmodel.h \
     homelocationutil.h \
     mytabbedstackwidget.h \