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

typedef enum  {
  FileFsVolumeInformation = 1,
  FileFsLabelInformation = 2,
  FileFsSizeInformation = 3,
  FileFsDeviceInformation = 4,
  FileFsAttributeInformation = 5,
  FileFsControlInformation = 6,
  FileFsFullSizeInformation = 7,
  FileFsObjectIdInformation = 8,
  FileFsDriverPathInformation = 9,
  FileFsVolumeFlagsInformation = 10,
  FileFsSectorSizeInformation = 11
} FS_INFORMATION_CLASS;

extern "C"
NTSTATUS WINAPI NtQueryVolumeInformationFile(
  _In_  HANDLE               FileHandle,
  _Out_ PIO_STATUS_BLOCK     IoStatusBlock,
  _Out_ PVOID                FsInformation,
  _In_  ULONG                Length,
  _In_  FS_INFORMATION_CLASS FsInformationClass
  );

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 hDisk = CreateFile(L"C:\\", 0, 0, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
  if (hDisk == INVALID_HANDLE_VALUE) {
    printf("CreateFile failed, %d\n", GetLastError());
    return 1;
  }

  // Obtain the output data, assuming that it will fit into 256 bytes.
  BYTE output[256];
  IO_STATUS_BLOCK iosb;
  NTSTATUS st = NtQueryVolumeInformationFile(hDisk, &iosb, output, sizeof(output), FileFsVolumeInformation);
  if (!NT_SUCCESS(st)) {
    printf("NtQueryVolumeInformationFile failed, %x\n", st);
    CloseHandle(hDisk);
    return 1;
  }

  // Dump the output data on screen and free resources.
  PrintHex(output, iosb.Information);
  CloseHandle(hDisk);

  return 0;
}