utils: added generic version number structs

server/src/utils/version.hpp

@@ -0,0 +1,96 @@
+/**
+ * server/src/utils/version.hpp
+ *
+ * This file is part of the traintastic source code.
+ *
+ * Copyright (C) 2022 Reinder Feenstra
+ *
+ * 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 2
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#ifndef TRAINTASTIC_SERVER_UTILS_VERSION_HPP
+#define TRAINTASTIC_SERVER_UTILS_VERSION_HPP
+
+#include <type_traits>
+#include "fromchars.hpp"
+
+namespace Version
+{
+  template<class T>
+  struct MajorMinor
+  {
+    static_assert(std::is_unsigned_v<T>);
+
+    using Type = T;
+
+    T major = 0;
+    T minor = 0;
+  };
+
+  template<class T>
+  struct MajorMinorPatch : MajorMinor<T>
+  {
+    T patch = 0;
+  };
+
+  template<class T>
+  std::from_chars_result fromChars(std::string_view sv, MajorMinor<T>& version)
+  {
+    T major;
+    auto r = ::fromChars(sv, major);
+    if(r.ec != std::errc())
+      return r;
+
+    if(r.ptr == (sv.data() + sv.size()) || *r.ptr != '.')
+      return {r.ptr, std::errc::invalid_argument};
+
+    T minor;
+    r = ::fromChars(sv.substr(1 + r.ptr - sv.data()), minor);
+
+    if(r.ec == std::errc())
+    {
+      version.major = major;
+      version.minor = minor;
+    }
+
+    return r;
+  }
+
+  template<class T>
+  std::from_chars_result fromChars(std::string_view sv, MajorMinorPatch<T>& version)
+  {
+    MajorMinor<T> mm;
+    auto r = fromChars(sv, mm);
+    if(r.ec != std::errc())
+      return r;
+
+    if(r.ptr == (sv.data() + sv.size()) || *r.ptr != '.')
+      return {r.ptr, std::errc::invalid_argument};
+
+    T patch;
+    r = ::fromChars(sv.substr(1 + r.ptr - sv.data()), patch);
+
+    if(r.ec == std::errc())
+    {
+      version.major = mm.major;
+      version.minor = mm.minor;
+      version.patch = patch;
+    }
+
+    return r;
+  }
+}
+
+#endif