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

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_ATTRIBUTE_NORMAL,
                            NULL);
  if (hDisk == INVALID_HANDLE_VALUE) {
    printf("CreateFile failed, %d\n", GetLastError());
    return 1;
  }
  
  // Obtain the output data, assuming that it will fit into 128 bytes.
  BYTE extents[128];
  DWORD BytesReturned;
  if (!DeviceIoControl(hDisk, IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS, NULL, 0, &extents, sizeof(extents), &BytesReturned, NULL)) {
    printf("DeviceIoControl failed, %d\n", GetLastError());
    CloseHandle(hDisk);
    return 1;
  }

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

  return 0;
}