Handle zero length Lua storage files more gracefully (#7823)

CHANGELOG.md

@@ -154,6 +154,7 @@
     Bug #7785: OpenMW-CS initialising Skill and Attribute fields to 0 instead of -1 on non-FortifyStat spells
     Bug #7794: Fleeing NPCs name tooltip doesn't appear
     Bug #7796: Absorbed enchantments don't restore magicka
+    Bug #7823: Game crashes when launching it.
     Bug #7832: Ingredient tooltips show magnitude for Fortify Maximum Magicka effect
     Bug #7840: First run of the launcher doesn't save viewing distance as the default value
     Bug #7841: Editor: "Dirty" water heights are saved in modified CELLs

components/lua/storage.cpp

@@ -239,8 +239,11 @@ namespace LuaUtil
         assert(mData.empty()); // Shouldn't be used before loading
         try
         {
-            Log(Debug::Info) << "Loading Lua storage \"" << path << "\" (" << std::filesystem::file_size(path)
-                             << " bytes)";
+            std::uintmax_t fileSize = std::filesystem::file_size(path);
+            Log(Debug::Info) << "Loading Lua storage \"" << path << "\" (" << fileSize << " bytes)";
+            if (fileSize == 0)
+                throw std::runtime_error("Storage file has zero length");
+
             std::ifstream fin(path, std::fstream::binary);
             std::string serializedData((std::istreambuf_iterator<char>(fin)), std::istreambuf_iterator<char>());
             sol::table data = deserialize(mLua, serializedData);
@@ -253,7 +256,7 @@ namespace LuaUtil
         }
         catch (std::exception& e)
         {
-            Log(Debug::Error) << "Can not read \"" << path << "\": " << e.what();
+            Log(Debug::Error) << "Cannot read \"" << path << "\": " << e.what();
         }
     }