options: don't create QSettings all the time

Update usages.

2 files changed, 33 insertions, 32 deletions

diff --git a/migration/20160906_00-mappings.cpp b/migration/20160906_00-mappings.cpp
index 58674843..a5184825 100644
--- a/migration/20160906_00-mappings.cpp
+++ b/migration/20160906_00-mappings.cpp
@@ -36,31 +36,30 @@ struct mappings_from_2_3_0_rc11 : migration
             "rz", "rz_alt",
         };
 
-        std::shared_ptr<QSettings> settings_ = options::group::ini_file();
-        QSettings& settings(*settings_);
-
-        for (const char* name : names)
-        {
-            QList<QPointF> points;
+        return group::with_settings_object([&](QSettings& settings) {
+            for (const char* name : names)
+            {
+                QList<QPointF> points;
 
-            settings.beginGroup(QString("Curves-%1").arg(name));
+                settings.beginGroup(QString("Curves-%1").arg(name));
 
-            const int max = settings.value("point-count", 0).toInt();
+                const int max = settings.value("point-count", 0).toInt();
 
-            for (int i = 0; i < max; i++)
-            {
-                QPointF new_point(settings.value(QString("point-%1-x").arg(i), 0).toDouble(),
-                                  settings.value(QString("point-%1-y").arg(i), 0).toDouble());
+                for (int i = 0; i < max; i++)
+                {
+                    QPointF new_point(settings.value(QString("point-%1-x").arg(i), 0).toDouble(),
+                                      settings.value(QString("point-%1-y").arg(i), 0).toDouble());
 
-                points.append(new_point);
-            }
+                    points.append(new_point);
+                }
 
-            settings.endGroup();
+                settings.endGroup();
 
-            ret.append(points);
-        }
+                ret.append(points);
+            }
 
-        return ret;
+            return ret;
+        });
     }
 
     QString unique_date() const override { return "20160909_00"; }
@@ -94,9 +93,6 @@ struct mappings_from_2_3_0_rc11 : migration
         const QList<QList<QPointF>> old_mappings = get_old_splines();
         Mappings m = get_new_mappings();
 
-        std::shared_ptr<QSettings> s_ = options::group::ini_file();
-        QSettings& s = *s_;
-
         for (int i = 0; i < 12; i++)
         {
             spline& spl = (i % 2) == 0 ? m(i / 2).spline_main : m(i / 2).spline_alt;
@@ -104,7 +100,7 @@ struct mappings_from_2_3_0_rc11 : migration
             const QList<QPointF>& points = old_mappings[i];
             for (const QPointF& pt : points)
                 spl.add_point(pt);
-            spl.save(s);
+            spl.save();
         }
     }
 };
diff --git a/migration/migration.cpp b/migration/migration.cpp
index bb8386fc..747ea06b 100644
--- a/migration/migration.cpp
+++ b/migration/migration.cpp
@@ -78,11 +78,11 @@ QString migrator::last_migration_time()
 {
     QString ret;
 
-    std::shared_ptr<QSettings> s(options::group::ini_file());
-
-    s->beginGroup("migrations");
-    ret = s->value("last-migration-at", "19700101_00").toString();
-    s->endGroup();
+    options::group::with_settings_object([&](QSettings& s) {
+        s.beginGroup("migrations");
+        ret = s.value("last-migration-at", "19700101_00").toString();
+        s.endGroup();
+    });
 
     return ret;
 }
@@ -102,11 +102,16 @@ QString migrator::time_after_migrations()
 
 void migrator::set_last_migration_time(const QString& val)
 {
-    std::shared_ptr<QSettings> s(options::group::ini_file());
-
-    s->beginGroup("migrations");
-    s->setValue("last-migration-at", val);
-    s->endGroup();
+    options::group::with_settings_object([&](QSettings& s) {
+        s.beginGroup("migrations");
+        const QString old_value = s.value("last-migration-at", "").toString();
+        if (val != old_value)
+        {
+            s.setValue("last-migration-at", val);
+            options::group::mark_ini_modified();
+        }
+        s.endGroup();
+    });
 }
 
 std::vector<migration*> migrator::sorted_migrations()