www.pudn.com > RemoveDriveByLetter_demo.zip > RemoveDriveByLetter.cpp

// 
// RemoveDriveByLetter.cpp by Uwe Sieber - www.uwe-sieber.de 
// 
// Simple demonstration how to prepare a disk drive for save removal 
// 
// Works with removable and fixed drives under W2K, XP, W2K3, Vista 
// 
// Console application - expects the drive letter of the drive to remove as parameter 
// 
// you are free to use this code in your projects 
// 
 
 
#include "stdafx.h" 
#include  
 
#include  
 
#include  
#include  
#include  
#include  
 
//------------------------------------------------- 
DEVINST GetDrivesDevInstByDeviceNumber(long DeviceNumber, UINT DriveType, char* szDosDeviceName); 
//------------------------------------------------- 
 
 
 
//------------------------------------------------- 
int main(int argc, char* argv[]) 
{ 
 
	if ( argc != 2 ) { 
		return 1;		 
	} 
 
	char DriveLetter = argv[1][0]; 
	DriveLetter &= ~0x20; // uppercase 
 
	if ( DriveLetter < 'A' || DriveLetter > 'Z' ) { 
		return 1; 
	} 
 
	char szRootPath[] = "X:\\";   // "X:\"  -> for GetDriveType 
	szRootPath[0] = DriveLetter; 
 
	char szDevicePath[] = "X:";   // "X:"   -> for QueryDosDevice 
	szDevicePath[0] = DriveLetter; 
 
	char szVolumeAccessPath[] = "\\\\.\\X:";   // "\\.\X:"  -> to open the volume 
	szVolumeAccessPath[4] = DriveLetter; 
 
	long DeviceNumber = -1; 
 
	// open the storage volume 
	HANDLE hVolume = CreateFile(szVolumeAccessPath, 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, NULL, NULL); 
	if (hVolume == INVALID_HANDLE_VALUE) { 
		return 1; 
	} 
 
	// get the volume's device number 
	STORAGE_DEVICE_NUMBER sdn; 
	DWORD dwBytesReturned = 0; 
	long res = DeviceIoControl(hVolume, IOCTL_STORAGE_GET_DEVICE_NUMBER, NULL, 0, &sdn, sizeof(sdn), &dwBytesReturned, NULL); 
	if ( res ) { 
		DeviceNumber = sdn.DeviceNumber; 
	} 
	CloseHandle(hVolume); 
 
	if ( DeviceNumber == -1 ) { 
		return 1; 
	} 
 
	// get the drive type which is required to match the device numbers correctely 
	UINT DriveType = GetDriveType(szRootPath); 
 
	// get the dos device name (like \device\floppy0) to decide if it's a floppy or not - who knows a better way? 
	char szDosDeviceName[MAX_PATH]; 
	res = QueryDosDevice(szDevicePath, szDosDeviceName, MAX_PATH); 
	if ( !res ) { 
		return 1; 
	} 
 
	// get the device instance handle of the storage volume by means of a SetupDi enum and matching the device number 
	DEVINST DevInst = GetDrivesDevInstByDeviceNumber(DeviceNumber, DriveType, szDosDeviceName); 
 
	if ( DevInst == 0 ) { 
		return 1; 
	} 
 
	PNP_VETO_TYPE VetoType = PNP_VetoTypeUnknown;  
	WCHAR VetoNameW[MAX_PATH]; 
	VetoNameW[0] = 0; 
	bool bSuccess = false; 
 
	// get drives's parent, e.g. the USB bridge, the SATA port, an IDE channel with two drives! 
	DEVINST DevInstParent = 0; 
	res = CM_Get_Parent(&DevInstParent, DevInst, 0);  
 
	for ( long tries=1; tries<=3; tries++ ) { // sometimes we need some tries... 
 
		VetoNameW[0] = 0; 
 
		// CM_Query_And_Remove_SubTree doesn't work for restricted users 
		//res = CM_Query_And_Remove_SubTreeW(DevInstParent, &VetoType, VetoNameW, MAX_PATH, CM_REMOVE_NO_RESTART); // CM_Query_And_Remove_SubTreeA is not implemented under W2K! 
		//res = CM_Query_And_Remove_SubTreeW(DevInstParent, NULL, NULL, 0, CM_REMOVE_NO_RESTART);  // with messagebox (W2K) or balloon (XP) 
		 
		res = CM_Request_Device_EjectW(DevInstParent, &VetoType, VetoNameW, MAX_PATH, 0); 
		//res = CM_Request_Device_EjectW(DevInstParent, NULL, NULL, 0, 0); // with messagebox (W2K) or balloon (XP) 
 
		bSuccess = (res==CR_SUCCESS && VetoType==PNP_VetoTypeUnknown); 
		if ( bSuccess )  {  
			break; 
		} 
 
		Sleep(500); // required to give the next tries a chance! 
	} 
 
	if ( bSuccess ) { 
		printf("Success\n\n"); 
		return 0; 
	} 
 
	printf("failed\n"); 
	 
	printf("Result=0x%2X\n", res); 
 
	if ( VetoNameW[0] ) { 
		printf("VetoName=%ws)\n\n", VetoNameW); 
	}	 
	return 1; 
} 
//----------------------------------------------------------- 
 
 
 
//---------------------------------------------------------------------- 
// returns the device instance handle of a storage volume or 0 on error 
//---------------------------------------------------------------------- 
DEVINST GetDrivesDevInstByDeviceNumber(long DeviceNumber, UINT DriveType, char* szDosDeviceName) 
{ 
	bool IsFloppy = (strstr(szDosDeviceName, "\\Floppy") != NULL); // who knows a better way? 
 
	GUID* guid; 
 
	switch (DriveType) { 
	case DRIVE_REMOVABLE: 
		if ( IsFloppy ) { 
			guid = (GUID*)&GUID_DEVINTERFACE_FLOPPY; 
		} else { 
			guid = (GUID*)&GUID_DEVINTERFACE_DISK; 
		} 
		break; 
	case DRIVE_FIXED: 
		guid = (GUID*)&GUID_DEVINTERFACE_DISK; 
		break; 
	case DRIVE_CDROM: 
		guid = (GUID*)&GUID_DEVINTERFACE_CDROM; 
		break; 
	default: 
		return 0; 
	} 
 
	// Get device interface info set handle for all devices attached to system 
	HDEVINFO hDevInfo = SetupDiGetClassDevs(guid, NULL, NULL, DIGCF_PRESENT | DIGCF_DEVICEINTERFACE); 
 
	if (hDevInfo == INVALID_HANDLE_VALUE)	{ 
		return 0; 
	} 
 
	// Retrieve a context structure for a device interface of a device information set 
	DWORD dwIndex = 0; 
	SP_DEVICE_INTERFACE_DATA devInterfaceData = {0}; 
	devInterfaceData.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA); 
	long res; 
 
	BYTE Buf[1024]; 
	PSP_DEVICE_INTERFACE_DETAIL_DATA pspdidd = (PSP_DEVICE_INTERFACE_DETAIL_DATA)Buf; 
	SP_DEVICE_INTERFACE_DATA         spdid; 
	SP_DEVINFO_DATA                  spdd; 
	DWORD                            dwSize; 
	 
	spdid.cbSize = sizeof(spdid); 
 
	while ( true )	{ 
		res = SetupDiEnumDeviceInterfaces(hDevInfo, NULL, guid, dwIndex, &devInterfaceData); 
		if ( !res ) { 
			break; 
		} 
 
		SetupDiEnumInterfaceDevice(hDevInfo, NULL, guid, dwIndex, &spdid); 
 
		dwSize = 0; 
		SetupDiGetDeviceInterfaceDetail(hDevInfo, &spdid, NULL, 0, &dwSize, NULL); 
 
		if ( dwSize!=0 && dwSize<=sizeof(Buf) ) { 
 
			pspdidd->cbSize = sizeof(*pspdidd); // 5 Bytes! 
 
			ZeroMemory(&spdd, sizeof(spdd)); 
			spdd.cbSize = sizeof(spdd); 
 
			long res = SetupDiGetDeviceInterfaceDetail(hDevInfo, &spdid, pspdidd, dwSize, &dwSize, &spdd); 
			if ( res ) { 
 
				// in case you are interested in the USB serial number: 
				// the device instance id string contains the serial number if the  
				// device has one, otherwise a generated id that contains the '&' char... 
				/* 
				DEVINST DevInstParent = 0; 
				CM_Get_Parent(&DevInstParent, spdd.DevInst, 0);  
				char szDeviceIdString[MAX_PATH]; 
				CM_Get_Device_ID(DevInstParent, szDeviceIdString, MAX_PATH, 0); 
				printf("DevInstId=%s\n", szDeviceIdString); 
				*/ 
 
				// open the disk or cdrom or floppy 
				HANDLE hDrive = CreateFile(pspdidd->DevicePath, 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, NULL, NULL); 
				if ( hDrive != INVALID_HANDLE_VALUE ) { 
					// get its device number 
					STORAGE_DEVICE_NUMBER sdn; 
					DWORD dwBytesReturned = 0; 
					res = DeviceIoControl(hDrive, IOCTL_STORAGE_GET_DEVICE_NUMBER, NULL, 0, &sdn, sizeof(sdn), &dwBytesReturned, NULL); 
					if ( res ) { 
						if ( DeviceNumber == (long)sdn.DeviceNumber ) {  // match the given device number with the one of the current device 
							CloseHandle(hDrive); 
							SetupDiDestroyDeviceInfoList(hDevInfo); 
							return spdd.DevInst; 
						} 
					} 
					CloseHandle(hDrive); 
				} 
			} 
		} 
		dwIndex++; 
	} 
 
	SetupDiDestroyDeviceInfoList(hDevInfo); 
 
	return 0; 
} 
//-----------------------------------------------------------