feat: Add DConfig class

DConfig 用于读取程序配置文件，符合 DSG 标准：
https://gitlabwh.uniontech.com/wuhan/se/deepin-specifications/-/issues/3
当配置文件的DBus服务未注册时将直接使用 DConfigFile, 在非 Linux 系统上
使用 QSettings。

Log:
Change-Id: Id4ab32f9f5fc1d870b35203a3cb4d8476d28c839

src/DConfig

@@ -0,0 +1 @@
+#include "dconfig.h"

src/dbus/org.desktopspec.ConfigManager.Manager.xml

@@ -0,0 +1,40 @@
+<interface name='org.desktopspec.ConfigManager.Manager'>
+    <property access="read" type="s" name="version"/>
+    <property access="read" type="as" name="keyList"/>
+    <property access="read" type="b" name="canRead"/>
+    <property access="read" type="b" name="canWrite"/>
+    <property access="read" type="b" name="canOverride"/>
+    <!--为每个 key 提供一个只读属性，如：
+    <property access="read" type="v" name="key1"/>
+    ...
+    <property access="read" type="v" name="key2"/>
+    -->
+    <method name='value'>
+      <arg type='s' name='key' direction='in'/>
+      <arg type='v' name='value' direction='out'/>
+    </method>
+    <method name='setValue'>
+      <arg type='s' name='key' direction='in'/>
+      <arg type='v' name='value' direction='in'/>
+    </method>
+    <method name='name'>
+      <arg type='s' name='key' direction='in'/>
+      <arg type='s' name='language' direction='in'/>
+      <arg type='s' name='name' direction='out'/>
+    </method>
+    <method name='description'>
+      <arg type='s' name='key' direction='in'/>
+      <arg type='s' name='language' direction='in'/>
+      <arg type='s' name='description' direction='out'/>
+    </method>
+    <method name='visibility'>
+      <arg type='s' name='key' direction='in'/>
+      <arg type='s' name='visibility' direction='out'/>
+    </method>
+    <!--采用引用计数的方式，引用为 0 时才真正的销毁-->
+    <method name='release'>
+    </method>
+    <signal name="valueChanged">
+      <arg name="key" type="s" direction="out"/>'
+    </signal>
+</interface>

src/dbus/org.desktopspec.ConfigManager.xml

@@ -0,0 +1,8 @@
+<interface name='org.desktopspec.ConfigManager'>
+    <method name='acquireManager'>
+      <arg type='s' name='appid' direction='in'/>
+      <arg type='s' name='name' direction='in'/>
+      <arg type='s' name='subpath' direction='in'/>
+      <arg type='o' name='path' direction='out'/>
+    </method>
+</interface>

src/dconfig.cpp

@@ -0,0 +1,220 @@
+/*
+ * Copyright (C) 2021 Uniontech Technology Co., Ltd.
+ *
+ * Author:     zccrs <zccrs@live.com>
+ *
+ * Maintainer: zccrs <zhangjide@uniontech.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * 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 Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "dconfig.h"
+#ifndef D_DISABLE_DCONFIG
+#include "dconfigfile.h"
+#ifndef D_DISABLE_DBUS_CONFIG
+#include "configmanager_interface.h"
+#include "manager_interface.h"
+#endif
+#include <unistd.h>
+#include <pwd.h>
+#else
+#include <QSettings>
+#endif
+#include "dobject_p.h"
+
+#include <QLoggingCategory>
+#include <QCoreApplication>
+
+// https://gitlabwh.uniontech.com/wuhan/se/deepin-specifications/-/issues/3
+
+DCORE_BEGIN_NAMESPACE
+
+Q_DECLARE_LOGGING_CATEGORY(cfLog)
+
+#define DSG_CONFIG "org.desktopspec.ConfigManager"
+#define DSG_CONFIG_MANAGER "org.desktopspec.ConfigManager"
+
+inline static QString getAppId() {
+    // TODO: 应该使用更可靠的接口获取 appid
+    return QCoreApplication::applicationName();
+}
+
+class Q_DECL_HIDDEN DConfigPrivate : public DObjectPrivate
+{
+public:
+    DConfigPrivate(DConfig *qq)
+        : DObjectPrivate(qq)
+    {
+
+    }
+
+    QString name;
+    QString subpath;
+#ifndef D_DISABLE_DCONFIG
+    inline static QString getUserName() {
+        uid_t uid = geteuid();
+        passwd *pw = getpwuid(uid);
+        return pw ? QString::fromLocal8Bit(pw->pw_name) : QString();
+    }
+
+#ifndef D_DISABLE_DBUS_CONFIG
+    DSGConfigManager *config = nullptr;
+#endif
+    QScopedPointer<DConfigFile> configFile;
+
+    inline QStringList keyList() const {
+#ifndef D_DISABLE_DBUS_CONFIG
+        if (Q_LIKELY(config)) {
+            return config->keyList();
+        }
+#endif
+        return configFile->keyList();
+    }
+    inline QVariant value(const QString &key, const QVariant &fallback) const {
+#ifndef D_DISABLE_DBUS_CONFIG
+        if (Q_LIKELY(config)) {
+            const QDBusVariant &dv = config->value(key);
+            const QVariant &v = dv.variant();
+            return v.isValid() ? v : fallback;
+        }
+#endif
+        return configFile->value(key, fallback);
+    }
+    inline void setValue(const QString &key, const QVariant &value) {
+#ifndef D_DISABLE_DBUS_CONFIG
+        if (Q_LIKELY(config)) {
+            config->setValue(key, QDBusVariant(value));
+            return;
+        }
+#endif
+        configFile->setValue(key, value, getUserName(), getAppId());
+    }
+#else
+    QSettings *settings = nullptr;
+
+    inline QStringList keyList() const {
+        return settings->childKeys();
+    }
+    inline QVariant value(const QString &key, const QVariant &fallback) const {
+        return settings->value(key, fallback);
+    }
+    inline void setValue(const QString &key, const QVariant &value) {
+        settings->setValue(key, value);
+    }
+#endif
+
+    D_DECLARE_PUBLIC(DConfig)
+};
+
+DConfig::DConfig(const QString &name, const QString &subpath,
+                 QObject *parent)
+    : QObject(parent)
+    , DObject(*new DConfigPrivate(this))
+{
+    D_D(DConfig);
+    d->name = name;
+    d->subpath = subpath;
+}
+
+bool DConfig::load()
+{
+    D_D(DConfig);
+
+    const auto &appid = getAppId();
+    Q_ASSERT(!appid.isEmpty());
+
+    qCDebug(cfLog, "Load config of appid=%s name=%s, subpath=%s",
+            qPrintable(appid), qPrintable(d->name), qPrintable(d->subpath));
+
+#ifndef D_DISABLE_DCONFIG
+    bool use_dbus_config = false;
+#ifndef D_DISABLE_DBUS_CONFIG
+    if (d->config)
+        return true;
+
+    use_dbus_config = QDBusConnection::systemBus().interface()->isServiceRegistered(DSG_CONFIG);
+
+    if (use_dbus_config) {
+        qCDebug(cfLog, "Try acquire config manager object form DBus");
+        DSGConfig dsg_config(DSG_CONFIG, "/", QDBusConnection::systemBus());
+        const QDBusObjectPath dbus_path = dsg_config.acquireManager(appid, d->name, d->subpath);
+        if (dbus_path.path().isEmpty()) {
+            qCWarning(cfLog, "Can't acquire config manager");
+            return false;
+        } else {
+            d->config = new DSGConfigManager(DSG_CONFIG_MANAGER, dbus_path.path(),
+                                             QDBusConnection::systemBus(), this);
+            if (!d->config->isValid()) {
+                delete d->config;
+                d->config = nullptr;
+                return false;
+            } else {
+                connect(d->config, &DSGConfigManager::valueChanged, this, &DConfig::valueChanged);
+                use_dbus_config = true;
+            }
+        }
+    }
+#endif
+
+    if (!use_dbus_config) {
+        qCDebug(cfLog, "Can't use DBus config service, fallback to DConfigFile mode");
+        if (d->configFile)
+            return true;
+        d->configFile.reset(new DConfigFile(appid, d->name, d->subpath));
+    }
+#else
+    qCDebug(cfLog, "Fallback to QSettings mode");
+    if (d->settings)
+        return true;
+
+    d->settings = new QSettings(d->name, QSettings::IniFormat, this);
+    d->settings->beginGroup(d->subpath);
+#endif
+
+    return true;
+}
+
+QStringList DConfig::keyList() const
+{
+    D_DC(DConfig);
+    return d->keyList();
+}
+
+bool DConfig::isValid() const
+{
+    D_DC(DConfig);
+#ifndef D_DISABLE_DCONFIG
+    if (d->configFile)
+        return true;
+
+#ifndef D_DISABLE_DBUS_CONFIG
+    return d->config;
+#endif
+#else
+    return d->settings;
+#endif
+}
+
+QVariant DConfig::value(const QString &key, const QVariant &fallback) const
+{
+    D_DC(DConfig);
+    return d->value(key, fallback);
+}
+
+void DConfig::setValue(const QString &key, const QVariant &value)
+{
+    D_D(DConfig);
+    d->setValue(key, value);
+}
+
+DCORE_END_NAMESPACE

src/dconfig.h

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2021 Uniontech Technology Co., Ltd.
+ *
+ * Author:     zccrs <zccrs@live.com>
+ *
+ * Maintainer: zccrs <zhangjide@uniontech.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * 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 Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef DCONFIG_H
+#define DCONFIG_H
+
+#include <dtkcore_global.h>
+#include <DObject>
+
+#include <QObject>
+#include <QVariant>
+
+DCORE_BEGIN_NAMESPACE
+
+class DConfigPrivate;
+class LIBDTKCORESHARED_EXPORT DConfig : public QObject, public DObject
+{
+    Q_OBJECT
+    D_DECLARE_PRIVATE(DConfig)
+
+    Q_PROPERTY(QStringList keyList READ keyList FINAL)
+
+public:
+    explicit DConfig(const QString &name, const QString &subpath = QString(),
+                     QObject *parent = nullptr);
+
+    bool load();
+
+    QStringList keyList() const;
+
+    bool isValid() const;
+    QVariant value(const QString &key, const QVariant &fallback = QVariant()) const;
+    void setValue(const QString &key, const QVariant &value);
+
+Q_SIGNALS:
+    void valueChanged(const QString &key);
+};
+
+DCORE_END_NAMESPACE
+
+#endif // DCONFIG_H

src/src.pro

@@ -11,11 +11,13 @@ QMAKE_CXXFLAGS_RELEASE += -fvisibility=hidden
 
 INCLUDEPATH += $$PWD
 HEADERS += $$PWD/dtkcore_global.h \
+    dconfig.h \
     dsysinfo.h \
     dsecurestring.h \
     ddesktopentry.h
 
 SOURCES += \
+    dconfig.cpp \
     dsysinfo.cpp \
     dsecurestring.cpp \
     ddesktopentry.cpp
@@ -26,6 +28,25 @@ linux: {
 
     SOURCES += \
         $$PWD/dconfigfile.cpp
+
+    # generic dbus interfaces
+    isEmpty(DTK_DISABLE_DBUS_CONFIG) {
+        QT += dbus
+
+        config.files = $$PWD/dbus/org.desktopspec.ConfigManager.xml
+        config.header_flags += -c DSGConfig -N
+        config.source_flags += -c DSGConfig -N
+
+        manager.files = $$PWD/dbus/org.desktopspec.ConfigManager.Manager.xml
+        manager.header_flags += -c DSGConfigManager -N
+        manager.source_flags += -c DSGConfigManager -N
+
+        DBUS_INTERFACES += config manager
+    } else {
+        DEFINES += D_DISABLE_DBUS_CONFIG
+    }
+} else {
+    DEFINES += D_DISABLE_DCONFIG
 }
 
 include($$PWD/base/base.pri)
@@ -46,7 +67,8 @@ includes.files += \
     $$PWD/DSysInfo \
     $$PWD/DSecureString \
     $$PWD/DDesktopEntry \
-    $$PWD/DConfigFile
+    $$PWD/DConfigFile \
+    $$PWD/DConfig
 
 INSTALLS += includes target