Re: How to get drive letter from USB device name
"jklioe" <ranu2006@gmail.com> wrote in message
news:1194875162.819885.140750@i38g2000prf.googlegroups.com...
thats becoz the application returns all the usb devices( all the mass
storage device that are connected to system) but I want to fetch the
drive letter of particular device .Well I have following information
related to device ,based on these information I want to fetch the
drive letter
1) device interface (Returned from - SetupDiEnumDeviceInterfaces &
SetupDiGetDeviceInterfaceDetailW)
2) Physical device object name (Returned from -
CM_Get_DevNode_Registry_Property)
3) class name of the devie (Retruned from -
CM_Get_DevNode_Registry_Property)
4) Service Informatione
5) general device handle ( CreateFile )
If you just iterate the drive letters from 'A' .. 'Z' then you can call this
function to get all kinds of info about the associated device, including the
bus type (whether it's USB or not), the VID/PID. This function returns the
bus type, but you can change the code to access the other info. Hopefully
with the VID/PID you should be able to get the device you're looking for:
---
LONG GetBusType( TCHAR chDrive )
{
// From http://www.codeproject.com/w2k/usbdisks.asp
typedef struct _STORAGE_DEVICE_DESCRIPTOR {
ULONG Version;
ULONG Size;
UCHAR DeviceType;
UCHAR DeviceTypeModifier;
BOOLEAN RemovableMedia;
BOOLEAN CommandQueueing;
ULONG VendorIdOffset;
ULONG ProductIdOffset;
ULONG ProductRevisionOffset;
ULONG SerialNumberOffset;
STORAGE_BUS_TYPE BusType;
ULONG RawPropertiesLength;
UCHAR RawDeviceProperties[1];
} STORAGE_DEVICE_DESCRIPTOR, *PSTORAGE_DEVICE_DESCRIPTOR;
// retrieve the properties of a storage device or adapter.
typedef enum _STORAGE_QUERY_TYPE {
PropertyStandardQuery = 0,
PropertyExistsQuery,
PropertyMaskQuery,
PropertyQueryMaxDefined
} STORAGE_QUERY_TYPE, *PSTORAGE_QUERY_TYPE;
// retrieve the properties of a storage device or adapter.
typedef enum _STORAGE_PROPERTY_ID {
StorageDeviceProperty = 0,
StorageAdapterProperty,
StorageDeviceIdProperty
} STORAGE_PROPERTY_ID, *PSTORAGE_PROPERTY_ID;
// retrieve the properties of a storage device or adapter.
typedef struct _STORAGE_PROPERTY_QUERY {
STORAGE_PROPERTY_ID PropertyId;
STORAGE_QUERY_TYPE QueryType;
UCHAR AdditionalParameters[1];
} STORAGE_PROPERTY_QUERY, *PSTORAGE_PROPERTY_QUERY;
// IOCTL control code
#define IOCTL_STORAGE_QUERY_PROPERTY CTL_CODE(IOCTL_STORAGE_BASE, 0x0500,
METHOD_BUFFERED, FILE_ANY_ACCESS)
LONG lBusType = -1; // default to invalid bus type
char szBuf[MAX_PATH];
wsprintf (szBuf, _T("\\\\?\\%c:"), chDrive, chDrive);
HANDLE hDevice = CreateFile( szBuf, GENERIC_READ, FILE_SHARE_READ |
FILE_SHARE_WRITE,
NULL, OPEN_EXISTING, NULL, NULL);
if (hDevice == INVALID_HANDLE_VALUE)
return lBusType;
BYTE byteBuf[sizeof(STORAGE_DEVICE_DESCRIPTOR) + 512 - 1];
PSTORAGE_DEVICE_DESCRIPTOR pDevDesc = (PSTORAGE_DEVICE_DESCRIPTOR) byteBuf;
pDevDesc->Size = sizeof(byteBuf);
STORAGE_PROPERTY_QUERY Query; // input param for query
DWORD dwOutBytes; // IOCTL output length
// specify the query type
Query.PropertyId = StorageDeviceProperty;
Query.QueryType = PropertyStandardQuery;
// Query using IOCTL_STORAGE_QUERY_PROPERTY
if ( ::DeviceIoControl ( hDevice, // device handle
IOCTL_STORAGE_QUERY_PROPERTY, // info of device property
&Query, sizeof(STORAGE_PROPERTY_QUERY), // input data buffer
pDevDesc, pDevDesc->Size, // output data buffer
&dwOutBytes, // out's length
(LPOVERLAPPED)NULL) )
{
lBusType = pDevDesc->BusType;
}
// Cleanup
CloseHandle(hDevice);
return lBusType;
}
---
-- David