move HAL and tests folder

src/fsfw_hal/linux/UnixFileGuard.h

@@ -0,0 +1,30 @@
+#ifndef LINUX_UTILITY_UNIXFILEGUARD_H_
+#define LINUX_UTILITY_UNIXFILEGUARD_H_
+
+#include <fcntl.h>
+#include <fsfw/returnvalues/HasReturnvaluesIF.h>
+#include <unistd.h>
+
+#include <string>
+
+class UnixFileGuard {
+ public:
+  static constexpr int READ_WRITE_FLAG = O_RDWR;
+  static constexpr int READ_ONLY_FLAG = O_RDONLY;
+  static constexpr int NON_BLOCKING_IO_FLAG = O_NONBLOCK;
+
+  static constexpr ReturnValue_t OPEN_FILE_FAILED = 1;
+
+  UnixFileGuard(std::string device, int* fileDescriptor, int flags,
+                std::string diagnosticPrefix = "");
+
+  virtual ~UnixFileGuard();
+
+  ReturnValue_t getOpenResult() const;
+
+ private:
+  int* fileDescriptor = nullptr;
+  ReturnValue_t openStatus = HasReturnvaluesIF::RETURN_OK;
+};
+
+#endif /* LINUX_UTILITY_UNIXFILEGUARD_H_ */