138 lines
3.6 KiB
C++
138 lines
3.6 KiB
C++
// this file almost totally copied from MSDN
|
|
|
|
#include <windows.h>
|
|
#include <stdio.h>
|
|
#include <winioctl.h>
|
|
|
|
#define LOCK_TIMEOUT 3000 // 10 Seconds
|
|
#define LOCK_RETRIES 20
|
|
|
|
static HANDLE OpenVolume(TCHAR cDriveLetter)
|
|
{
|
|
HANDLE hVolume;
|
|
UINT uDriveType;
|
|
wchar_t szVolumeName[8] = {0};
|
|
wchar_t szRootName[5] = {0};
|
|
DWORD dwAccessFlags = 0;
|
|
|
|
wsprintf(szRootName, L"%c:\\", cDriveLetter);
|
|
|
|
uDriveType = GetDriveType(szRootName);
|
|
switch(uDriveType) {
|
|
case DRIVE_REMOVABLE:
|
|
dwAccessFlags = GENERIC_READ | GENERIC_WRITE;
|
|
break;
|
|
case DRIVE_CDROM:
|
|
dwAccessFlags = GENERIC_READ;
|
|
break;
|
|
default:
|
|
printf("Cannot eject. Drive type is incorrect.\n");
|
|
return INVALID_HANDLE_VALUE;
|
|
}
|
|
|
|
wsprintf(szVolumeName, L"\\\\.\\%c:", cDriveLetter);
|
|
|
|
hVolume = CreateFile( szVolumeName,
|
|
dwAccessFlags,
|
|
FILE_SHARE_READ | FILE_SHARE_WRITE,
|
|
NULL,
|
|
OPEN_EXISTING,
|
|
0,
|
|
NULL );
|
|
|
|
if (hVolume == INVALID_HANDLE_VALUE)
|
|
printf("CreateFile error %d\n", GetLastError());
|
|
return hVolume;
|
|
}
|
|
|
|
static BOOL CloseVolume(HANDLE hVolume)
|
|
{
|
|
return CloseHandle(hVolume);
|
|
}
|
|
|
|
static 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;
|
|
}
|
|
|
|
static BOOL DismountVolume(HANDLE hVolume)
|
|
{
|
|
DWORD dwBytesReturned;
|
|
|
|
return DeviceIoControl( hVolume,
|
|
FSCTL_DISMOUNT_VOLUME,
|
|
NULL, 0,
|
|
NULL, 0,
|
|
&dwBytesReturned,
|
|
NULL);
|
|
}
|
|
|
|
static 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);
|
|
}
|
|
|
|
static int AutoEjectVolume(HANDLE hVolume)
|
|
{
|
|
DWORD dwBytesReturned;
|
|
|
|
return DeviceIoControl( hVolume,
|
|
IOCTL_STORAGE_EJECT_MEDIA,
|
|
NULL, 0,
|
|
NULL, 0,
|
|
&dwBytesReturned,
|
|
NULL);
|
|
}
|
|
|
|
BOOL EjectVolume(TCHAR cDriveLetter)
|
|
{
|
|
HANDLE hVolume;
|
|
|
|
BOOL fAutoEject = FALSE;
|
|
|
|
hVolume = OpenVolume(cDriveLetter);
|
|
if (hVolume == INVALID_HANDLE_VALUE)
|
|
return FALSE;
|
|
|
|
// Lock and dismount the volume.
|
|
if (LockVolume(hVolume) && DismountVolume(hVolume)) {
|
|
// 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) return TRUE;
|
|
else return FALSE;
|
|
} |