memmappedfile-fix (#115)

Co-authored-by: Metehan Tuncbilek <mtuncbilek95@gmail.com>
Reviewed-by: Georg Hagen <georg.hagen@madvoxel.com>
Co-authored-by: mtuncbilek <metehan.tuncbilek@madvoxel.com>
Co-committed-by: mtuncbilek <metehan.tuncbilek@madvoxel.com>

openVulkanoCpp/IO/MemMappedFileInternal.hpp

@@ -0,0 +1,50 @@
+/*
+* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+#pragma once
+
+#include "MemMappedFile.hpp"
+
+#ifdef _MSC_VER
+	#include <Windows.h>
+#else
+	#include <sys/mman.h>
+	#include <sys/types.h>
+	#include <sys/stat.h>
+	#include <fcntl.h>
+	#include <unistd.h>
+#endif
+
+namespace OpenVulkano
+{
+	class MemMappedFileInternal
+	{
+		friend class MemMappedFileWriteHelper;
+		friend class MemMappedFile;
+
+	public:
+		MemMappedFileInternal(const char* file, MemMappedFile::FileMode fileMode);
+		~MemMappedFileInternal();
+
+	private:
+#if defined(_MSC_VER)
+		bool InvalidHandle() const { return fileHandle == INVALID_HANDLE_VALUE || fileHandle == NULL; }
+#else
+		[[nodiscard]] bool InvalidHandle() const { return fileHandle == -1; }
+#endif
+
+	private:
+		void* address = nullptr;
+		size_t size = 0;
+
+#ifdef _MSC_VER
+		HANDLE fileHandle;
+		HANDLE fileMappingHandle;
+#else
+		int fileHandle;
+		struct stat fileStat;
+#endif
+	};
+}