Remove helper function FileSize

Use std::filesystem at caller site instead.

Signed-off-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>

source/lib/file/file_system.cpp

@@ -62,20 +62,6 @@ bool FileExists(const OsPath& pathname)
 }
 
 
-u64 FileSize(const OsPath& pathname)
-{
-	try
-	{
-		return static_cast<u64>(std::filesystem::file_size(pathname.string()));
-	}
-	catch (std::filesystem::filesystem_error& err)
-	{
-		debug_printf("FileSize: failed to get filesize for '%s', reason: %s\n", pathname.string8().c_str(), err.what());
-	}
-	return 0;
-}
-
-
 Status GetFileInfo(const OsPath& pathname, CFileInfo* pPtrInfo)
 {
 	try

source/lib/file/file_system.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2025 Wildfire Games.
+/* Copyright (C) 2026 Wildfire Games.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
@@ -38,9 +38,6 @@
 bool DirectoryExists(const OsPath& path);
 bool FileExists(const OsPath& pathname);
 
-u64 FileSize(const OsPath& pathname);
-
-
 // (bundling size and mtime avoids a second expensive call to stat())
 class CFileInfo
 {

source/ps/ModIo.cpp

@@ -558,8 +558,13 @@ bool ModIo::VerifyDownloadedFile(std::string& err)
 {
 	// Verify filesize, as a first basic download check.
 	{
-		u64 filesize = std::stoull(m_ModData[m_DownloadModID].properties.at("filesize"));
-		if (filesize != FileSize(m_DownloadFilePath))
+		std::error_code ec{};
+		const u64 fileSize{static_cast<u64>(std::filesystem::file_size(std::filesystem::path(m_DownloadFilePath.string()), ec))};
+		if (ec)
+			LOGERROR("Failed to get filesize for '%s', reason: %s", m_DownloadFilePath.string8().c_str(), ec.message());
+		const u64 expectedFileSize{std::stoull(m_ModData[m_DownloadModID].properties.at("filesize"))};
+
+		if (ec || fileSize != expectedFileSize)
 		{
 			err = g_L10n.Translate("Mismatched filesize.");
 			return false;