Ejecting CD-ROM

README.md

This has some changes from original http://support.microsoft.com/kb/165721, to be compiled by cygwin-gcc.

to compile:

$ gcc -o eject eject.c

run with drive letter:

$ ./eject d

eject.c

#include <windows.h>
#include <winioctl.h>
// #include <tchar.h>
#include <stdio.h>

// Prototypes

// BOOL EjectVolume(TCHAR cDriveLetter);
BOOL EjectVolume(char cDriveLetter);

// HANDLE OpenVolume(TCHAR cDriveLetter);
HANDLE OpenVolume(char cDriveLetter);
BOOL LockVolume(HANDLE hVolume);
BOOL DismountVolume(HANDLE hVolume);
BOOL PreventRemovalOfVolume(HANDLE hVolume, BOOL fPrevent);
BOOL AutoEjectVolume(HANDLE hVolume);
BOOL CloseVolume(HANDLE hVolume);

LPTSTR szVolumeFormat = TEXT("\\\\.\\%c:");
LPTSTR szRootFormat = TEXT("%c:\\");
LPTSTR szErrorFormat = TEXT("Error %d: %s\n");

void ReportError(LPTSTR szMsg)
{
  // _tprintf(szErrorFormat, GetLastError(), szMsg);
  printf(szErrorFormat, GetLastError(), szMsg);
}

// HANDLE OpenVolume(TCHAR cDriveLetter)
HANDLE OpenVolume(char cDriveLetter)
{
  HANDLE hVolume;
  UINT uDriveType;
  // TCHAR szVolumeName[8];
  // TCHAR szRootName[5];
  char szVolumeName[8];
  char szRootName[5];
  DWORD dwAccessFlags;

  wsprintf(szRootName, szRootFormat, cDriveLetter);

  uDriveType = GetDriveType(szRootName);
  switch(uDriveType) {
  case DRIVE_REMOVABLE:
    dwAccessFlags = GENERIC_READ | GENERIC_WRITE;
    break;
  case DRIVE_CDROM:
    dwAccessFlags = GENERIC_READ;
    break;
  default:
    // _tprintf(TEXT("Cannot eject.  Drive type is incorrect.\n"));
    printf(TEXT("Cannot eject.  Drive type is incorrect.\n"));
    return INVALID_HANDLE_VALUE;
  }

  wsprintf(szVolumeName, szVolumeFormat, cDriveLetter);

  hVolume = CreateFile(   szVolumeName,
                          dwAccessFlags,
                          FILE_SHARE_READ | FILE_SHARE_WRITE,
                          NULL,
                          OPEN_EXISTING,
                          0,
                          NULL );
  if (hVolume == INVALID_HANDLE_VALUE)
    ReportError(TEXT("CreateFile"));

  return hVolume;
}

BOOL CloseVolume(HANDLE hVolume)
{
  return CloseHandle(hVolume);
}

#define LOCK_TIMEOUT        10000       // 10 Seconds
#define LOCK_RETRIES        20

BOOL LockVolume(HANDLE hVolume)
{
  DWORD dwBytesReturned;
  DWORD dwSleepAmount;
  int nTryCount;

  dwSleepAmount = LOCK_TIMEOUT / LOCK_RETRIES;

  // Do this in a loop until a timeout period has expired
  for (nTryCount = 0; nTryCount < LOCK_RETRIES; nTryCount++) {
    if (DeviceIoControl(hVolume,
                        FSCTL_LOCK_VOLUME,
                        NULL, 0,
                        NULL, 0,
                        &dwBytesReturned,
                        NULL))
      return TRUE;

    Sleep(dwSleepAmount);
  }

  return FALSE;
}

BOOL DismountVolume(HANDLE hVolume)
{
  DWORD dwBytesReturned;

  return DeviceIoControl( hVolume,
                          FSCTL_DISMOUNT_VOLUME,
                          NULL, 0,
                          NULL, 0,
                          &dwBytesReturned,
                          NULL);
}

BOOL PreventRemovalOfVolume(HANDLE hVolume, BOOL fPreventRemoval)
{
  DWORD dwBytesReturned;
  PREVENT_MEDIA_REMOVAL PMRBuffer;

  PMRBuffer.PreventMediaRemoval = fPreventRemoval;

  return DeviceIoControl( hVolume,
                          IOCTL_STORAGE_MEDIA_REMOVAL,
                          &PMRBuffer, sizeof(PREVENT_MEDIA_REMOVAL),
                          NULL, 0,
                          &dwBytesReturned,
                          NULL);
}

AutoEjectVolume(HANDLE hVolume)
{
  DWORD dwBytesReturned;

  return DeviceIoControl( hVolume,
                          IOCTL_STORAGE_EJECT_MEDIA,
                          NULL, 0,
                          NULL, 0,
                          &dwBytesReturned,
                          NULL);
}

// BOOL EjectVolume(TCHAR cDriveLetter)
BOOL EjectVolume(char cDriveLetter)
{
  HANDLE hVolume;

  BOOL fRemoveSafely = FALSE;
  BOOL fAutoEject = FALSE;

  // Open the volume.
  hVolume = OpenVolume(cDriveLetter);
  if (hVolume == INVALID_HANDLE_VALUE)
    return FALSE;

  // Lock and dismount the volume.
  if (LockVolume(hVolume) && DismountVolume(hVolume)) {
    fRemoveSafely = TRUE;

    // Set prevent removal to false and eject the volume.
    if (PreventRemovalOfVolume(hVolume, FALSE) &&
        AutoEjectVolume(hVolume))
      fAutoEject = TRUE;
  }

  // Close the volume so other processes can use the drive.
  if (!CloseVolume(hVolume))
    return FALSE;

  if (fAutoEject)
    printf("Media in Drive %c has been ejected safely.\n",
           cDriveLetter);
  else {
    if (fRemoveSafely)
      printf("Media in Drive %c can be safely removed.\n",
             cDriveLetter);
  }

  return TRUE;
}

void Usage()
{
  printf("Usage: Eject <drive letter>\n\n");
  return ;
}

void main(int argc, char * argv[])
{
  if (argc != 2) {
    Usage();
    return ;
  }

  if (!EjectVolume(argv[1][0]))
    printf("Failure ejecting drive %c.\n", argv[1][0]);

  return ;
}