#include <Windows.h>
#include <winternl.h>
#include <cstdio>

#define FileBothDirectoryInformation ((FILE_INFORMATION_CLASS)3)

extern "C"
NTSTATUS WINAPI NtQueryDirectoryFile(
  _In_     HANDLE                 FileHandle,
  _In_opt_ HANDLE                 Event,
  _In_opt_ PIO_APC_ROUTINE        ApcRoutine,
  _In_opt_ PVOID                  ApcContext,
  _Out_    PIO_STATUS_BLOCK       IoStatusBlock,
  _Out_    PVOID                  FileInformation,
  _In_     ULONG                  Length,
  _In_     FILE_INFORMATION_CLASS FileInformationClass,
  _In_     BOOLEAN                ReturnSingleEntry,
  _In_opt_ PUNICODE_STRING        FileName,
  _In_     BOOLEAN                RestartScan
  );

VOID PrintHex(PBYTE Data, ULONG dwBytes) {
  for (ULONG i = 0; i < dwBytes; i += 16) {
    printf("%.8x: ", i);

    for (ULONG j = 0; j < 16; j++) {
      if (i + j < dwBytes) {
        printf("%.2x ", Data[i + j]);
      }
      else {
        printf("?? ");
      }
    }

    for (ULONG j = 0; j < 16; j++) {
      if (i + j < dwBytes && Data[i + j] >= 0x20 && Data[i + j] <= 0x7e) {
        printf("%c", Data[i + j]);
      }
      else {
        printf(".");
      }
    }

    printf("\n");
  }
}

int main() {
  // Open the disk device.
  HANDLE hDir = CreateFile(L"C:\\Windows", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
  if (hDir == INVALID_HANDLE_VALUE) {
    printf("CreateFile failed, %d\n", GetLastError());
    return 1;
  }

  // Obtain the output data, assuming that it will fit into 1024 bytes.
  IO_STATUS_BLOCK iosb;
  UNICODE_STRING FileName;
  RtlInitUnicodeString(&FileName, L"explorer.exe");

  BYTE OutputBuffer[1024];
  RtlZeroMemory(OutputBuffer, sizeof(OutputBuffer));

  NTSTATUS st = NtQueryDirectoryFile(hDir, NULL, NULL, NULL, &iosb, OutputBuffer, sizeof(OutputBuffer), FileBothDirectoryInformation, TRUE, &FileName, FALSE);
  if (NT_SUCCESS(st)) {
    PrintHex(OutputBuffer, iosb.Information);
  } else {
    printf("NtQueryDirectoryFile failed, %x\n", st);
  }
    
  CloseHandle(hDir);

  return 0;
}