3 files changed, 54 insertions, 1 deletions

diff --git a/drivers/windows/file_access_windows.cpp b/drivers/windows/file_access_windows.cpp
index 37a94ce4cc..ea40622afc 100644
--- a/drivers/windows/file_access_windows.cpp
+++ b/drivers/windows/file_access_windows.cpp
@@ -34,7 +34,6 @@
 
 #include "core/os/os.h"
 #include "core/string/print_string.h"
-
 #include <share.h> // _SH_DENYNO
 #include <shlwapi.h>
 #define WIN32_LEAN_AND_MEAN
@@ -58,7 +57,27 @@ void FileAccessWindows::check_errors() const {
 	}
 }
 
+bool FileAccessWindows::is_path_invalid(const String &p_path) {
+	// Check for invalid operating system file.
+	String fname = p_path;
+	int dot = fname.find(".");
+	if (dot != -1) {
+		fname = fname.substr(0, dot);
+	}
+	fname = fname.to_lower();
+	return invalid_files.has(fname);
+}
+
 Error FileAccessWindows::open_internal(const String &p_path, int p_mode_flags) {
+	if (is_path_invalid(p_path)) {
+#ifdef DEBUG_ENABLED
+		if (p_mode_flags != READ) {
+			WARN_PRINT("The path :" + p_path + " is a reserved Windows system pipe, so it can't be used for creating files.");
+		}
+#endif
+		return ERR_INVALID_PARAMETER;
+	}
+
 	_close();
 
 	path_src = p_path;
@@ -313,6 +332,10 @@ void FileAccessWindows::store_buffer(const uint8_t *p_src, uint64_t p_length) {
 }
 
 bool FileAccessWindows::file_exists(const String &p_name) {
+	if (is_path_invalid(p_name)) {
+		return false;
+	}
+
 	String filename = fix_path(p_name);
 	FILE *g = _wfsopen((LPCWSTR)(filename.utf16().get_data()), L"rb", _SH_DENYNO);
 	if (g == nullptr) {
@@ -324,6 +347,10 @@ bool FileAccessWindows::file_exists(const String &p_name) {
 }
 
 uint64_t FileAccessWindows::_get_modified_time(const String &p_file) {
+	if (is_path_invalid(p_file)) {
+		return 0;
+	}
+
 	String file = fix_path(p_file);
 	if (file.ends_with("/") && file != "/") {
 		file = file.substr(0, file.length() - 1);
@@ -352,4 +379,20 @@ FileAccessWindows::~FileAccessWindows() {
 	_close();
 }
 
+HashSet<String> FileAccessWindows::invalid_files;
+
+void FileAccessWindows::initialize() {
+	static const char *reserved_files[]{
+		"con", "prn", "aux", "nul", "com0", "com1", "com2", "com3", "com4", "com5", "com6", "com7", "com8", "com9", "lpt0", "lpt1", "lpt2", "lpt3", "lpt4", "lpt5", "lpt6", "lpt7", "lpt8", "lpt9", nullptr
+	};
+	int reserved_file_index = 0;
+	while (reserved_files[reserved_file_index] != nullptr) {
+		invalid_files.insert(reserved_files[reserved_file_index]);
+		reserved_file_index++;
+	}
+}
+void FileAccessWindows::finalize() {
+	invalid_files.clear();
+}
+
 #endif // WINDOWS_ENABLED
diff --git a/drivers/windows/file_access_windows.h b/drivers/windows/file_access_windows.h
index 832cef3363..2b9960d494 100644
--- a/drivers/windows/file_access_windows.h
+++ b/drivers/windows/file_access_windows.h
@@ -50,6 +50,9 @@ class FileAccessWindows : public FileAccess {
 
 	void _close();
 
+	static bool is_path_invalid(const String &p_path);
+	static HashSet<String> invalid_files;
+
 public:
 	virtual Error open_internal(const String &p_path, int p_mode_flags) override; ///< open a file
 	virtual bool is_open() const override; ///< true when file is open
@@ -79,6 +82,9 @@ public:
 	virtual uint32_t _get_unix_permissions(const String &p_file) override;
 	virtual Error _set_unix_permissions(const String &p_file, uint32_t p_permissions) override;
 
+	static void initialize();
+	static void finalize();
+
 	FileAccessWindows() {}
 	virtual ~FileAccessWindows();
 };
diff --git a/platform/windows/os_windows.cpp b/platform/windows/os_windows.cpp
index 2a44a19085..d10ceca6a4 100644
--- a/platform/windows/os_windows.cpp
+++ b/platform/windows/os_windows.cpp
@@ -210,6 +210,8 @@ void OS_Windows::initialize() {
 	} else if (!dwrite2_init) {
 		print_verbose("Unable to load IDWriteFactory2, automatic system font fallback is disabled.");
 	}
+
+	FileAccessWindows::initialize();
 }
 
 void OS_Windows::delete_main_loop() {
@@ -252,6 +254,8 @@ void OS_Windows::finalize() {
 }
 
 void OS_Windows::finalize_core() {
+	FileAccessWindows::finalize();
+
 	timeEndPeriod(1);
 
 	memdelete(process_map);