add support for migrations

They're run from the UI thread so can even be interactive.

6 files changed, 245 insertions, 0 deletions

diff --git a/migration/20160906_0-mappings.cpp b/migration/20160906_0-mappings.cpp
new file mode 100644
index 00000000..0ff3095a
--- /dev/null
+++ b/migration/20160906_0-mappings.cpp
@@ -0,0 +1,14 @@
+#include "migration.hpp"
+
+#include <QDebug>
+
+using namespace migrations;
+
+struct foo : migration
+{
+    const QString& unique_date() const override { qDebug() << "foo"; static QString ret(""); return ret; }
+    bool should_run() const override { qDebug() << "bar"; return false; }
+    bool run() override { return false; }
+};
+
+OPENTRACK_MIGRATION(foo);
diff --git a/migration/20160906_1-axis-signs.cpp b/migration/20160906_1-axis-signs.cpp
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/migration/20160906_1-axis-signs.cpp
diff --git a/migration/CMakeLists.txt b/migration/CMakeLists.txt
new file mode 100644
index 00000000..d220b002
--- /dev/null
+++ b/migration/CMakeLists.txt
@@ -0,0 +1,2 @@
+opentrack_boilerplate(opentrack-migration BIN)
+target_link_libraries(opentrack-migration opentrack-logic opentrack-spline-widget)
diff --git a/migration/export.hpp b/migration/export.hpp
new file mode 100644
index 00000000..800ddf35
--- /dev/null
+++ b/migration/export.hpp
@@ -0,0 +1,28 @@
+#pragma once
+
+#ifdef BUILD_migration
+#   ifdef _WIN32
+#       define OPENTRACK_MIGRATION_LINKAGE __declspec(dllexport)
+#   else
+#       define OPENTRACK_MIGRATION_LINKAGE
+#   endif
+
+#   ifndef _MSC_VER
+#       define OPENTRACK_MIGRATION_EXPORT __attribute__ ((visibility ("default"))) OPENTRACK_MIGRATION_LINKAGE
+#   else
+#       define OPENTRACK_MIGRATION_EXPORT OPENTRACK_MIGRATION_LINKAGE
+#   endif
+
+#else
+    #ifdef _WIN32
+    #    define OPENTRACK_MIGRATION_LINKAGE __declspec(dllimport)
+    #else
+    #    define OPENTRACK_MIGRATION_LINKAGE
+    #endif
+
+    #ifndef _MSC_VER
+    #    define OPENTRACK_MIGRATION_EXPORT __attribute__ ((visibility ("default"))) OPENTRACK_MIGRATION_LINKAGE
+    #else
+    #    define OPENTRACK_MIGRATION_EXPORT OPENTRACK_MIGRATION_LINKAGE
+    #endif
+#endif
diff --git a/migration/migration.cpp b/migration/migration.cpp
new file mode 100644
index 00000000..6e54de19
--- /dev/null
+++ b/migration/migration.cpp
@@ -0,0 +1,129 @@
+#include "migration.hpp"
+
+#include "options/options.hpp"
+#include "compat/util.hpp"
+
+#include <QString>
+#include <QSettings>
+#include <QDebug>
+
+#include <memory>
+
+namespace migrations {
+
+namespace detail {
+
+void migrator::register_migration(migration* m)
+{
+    migrations().push_back(m);
+}
+
+migrator::vec& migrator::migrations()
+{
+    static vec ret;
+    return ret;
+}
+
+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();
+
+    return ret;
+}
+
+QString migrator::time_after_migrations()
+{
+    const vec list = sorted_migrations();
+
+    if (list.size() == 0u)
+        return QStringLiteral("19700101_00");
+
+    QString ret = list[list.size() - 1]->unique_date();
+    ret += QStringLiteral("~");
+
+    return ret;
+}
+
+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();
+}
+
+migrator::vec migrator::sorted_migrations()
+{
+    vec list(migrations());
+    std::sort(list.begin(), list.end(), [](const mm x, const mm y) { return x->unique_date() < y->unique_date(); });
+    return list;
+}
+
+std::vector<QString> migrator::run()
+{
+    vec migrations = sorted_migrations();
+    vstr done;
+
+    const QString last_migration = last_migration_time();
+
+    qDebug() << "migration: config" << options::group::ini_filename() << "time" << last_migration;
+
+    for (migration* m_ : migrations)
+    {
+        migration& m(*m_);
+
+        const QString date = m.unique_date();
+
+        if (date <= last_migration)
+            continue;
+
+        if (m.should_run())
+        {
+            m.run();
+            done.push_back(m.name());
+        }
+    }
+
+    mark_config_as_not_needing_migration();
+
+    if (done.size())
+    {
+        qDebug() << "migration: done" << done.size() << "units";
+        for (const QString& name : done)
+            qDebug() << "--" << name;
+        qDebug() << "";
+    }
+
+    return done;
+}
+
+}
+
+migration::migration() {}
+migration::~migration() {}
+
+} // ns
+
+std::vector<QString> run_migrations()
+{
+    return migrations::detail::migrator::run();
+}
+
+void mark_config_as_not_needing_migration()
+{
+    using m = migrations::detail::migrator;
+
+    m::mark_config_as_not_needing_migration();
+}
+
+void migrations::detail::migrator::mark_config_as_not_needing_migration()
+{
+    set_last_migration_time(time_after_migrations());
+}
diff --git a/migration/migration.hpp b/migration/migration.hpp
new file mode 100644
index 00000000..b9c20f15
--- /dev/null
+++ b/migration/migration.hpp
@@ -0,0 +1,72 @@
+#pragma once
+
+#include <QString>
+#include <vector>
+
+#include "export.hpp"
+
+namespace migrations {
+
+class migration;
+class registrator;
+
+namespace detail {
+    class migrator final
+    {
+        using mm = migration*;
+        template<typename t> using vec_ = std::vector<t>;
+        using vstr = vec_<QString>;
+        using vec = vec_<mm>;
+        static vec& migrations();
+        static QString last_migration_time();
+        static QString time_after_migrations();
+        static void set_last_migration_time(const QString& val);
+        migrator() = delete;
+        static vec sorted_migrations();
+    public:
+        static vstr run();
+        static void register_migration(migration* m);
+        static void mark_config_as_not_needing_migration();
+    };
+
+    template<typename t>
+    struct registrator final
+    {
+        registrator()
+        {
+            static t m;
+            migrator::register_migration(static_cast<migration*>(&m));
+        }
+    };
+}
+
+#ifndef __COUNTER__
+#   error "oops, need __COUNTER__ extension for preprocessor"
+#endif
+
+#define OPENTRACK_MIGRATION(type) static ::migrations::detail::registrator<type> opentrack_migration_registrator__ ## __COUNTER__ ## _gensym;
+
+#ifdef Q_CREATOR_RUN
+#   pragma clang diagnostic ignored "-Wweak-vtables"
+#endif
+
+class migration
+{
+    migration& operator=(const migration&) = delete;
+    migration(const migration&) = delete;
+    migration& operator=(migration&&) = delete;
+    migration(migration&&) = delete;
+
+public:
+    migration();
+    virtual ~migration();
+    virtual QString unique_date() const = 0;
+    virtual QString name() const = 0;
+    virtual bool should_run() const = 0;
+    virtual void run() = 0;
+};
+
+}
+
+OPENTRACK_MIGRATION_EXPORT std::vector<QString> run_migrations();
+OPENTRACK_MIGRATION_EXPORT void mark_config_as_not_needing_migration();