前面我们介绍了枚举系统中的U盘盘符（见《Windows下USB磁盘开发系列一：枚举系统中U盘的盘符》）、以及获取USB设备的信息（见《Windows下USB磁盘开发系列二：枚举系统中所有USB设备》）。有个时候我们不仅仅需要获取U盘盘符（路径），而且需要获取该U盘的硬件信息，比如厂商、friendly name、描述等等。那么我们可以通过前面两个方法，把U盘盘符和设备信息匹配起来吗？答案是肯定的，下面介绍具体的实现方法。
具体方法如下：
1，获取U盘盘符（路径）；
2，对U盘路径调用CreateFile()获取U盘句柄；
3，对U盘句柄调用DeviceIoControl()获取其Device Number；
4，调用SetupDiGetClassDevs()/SetupDiEnumDeviceInfo()枚举系统中所有U盘设备；
5，调用SetupDiEnumDeviceInterfaces()/SetupDiGetDeviceInterfaceDetail()获取设备路径；
6，对U盘设备路径调用CreateFile()获取U盘设备句柄；
7，对U盘设备句柄调用DeviceIoControl()获取其Device Number；
8，判断3和7获得的Device Number，两者一致则表示该U盘盘符和设备为同一设备。
具体实现代码如下：
1，获取U盘设备列表
int get_usb_device_list(usb_device_info *usb_list, int list_size)
{
int usb_device_cnt = 0; char disk_path[5] = {0};
char device_path[10] = {0};
DWORD all_disk = GetLogicalDrives(); int i = 0;
DWORD bytes_returned = 0;
STORAGE_DEVICE_NUMBER device_num;
while (all_disk && usb_device_cnt < list_size)
{
if ((all_disk & 0x1) == 1)
{
sprintf_s(disk_path, "%c:", 'A'+i);
sprintf_s(device_path, "\\\\.\\%s", disk_path);
if (GetDriveTypeA(disk_path) == DRIVE_REMOVABLE)
{
// get this usb device id
HANDLE hDevice = CreateFileA(device_path, 0, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);
if (DeviceIoControl(hDevice, IOCTL_STORAGE_GET_DEVICE_NUMBER,
NULL, 0,
&device_num, sizeof(device_num),
&bytes_returned, (LPOVERLAPPED) NULL))
{
usb_list[usb_device_cnt].volume = 'A' + i;
usb_list[usb_device_cnt].device_num = device_num.DeviceNumber;
usb_device_cnt++;
}
CloseHandle(hDevice);
hDevice = 0;
}
}
all_disk = all_disk >> 1;
i++;
} return usb_device_cnt;
}
2，匹配U盘设备信息
int get_usb_device_friendname(usb_device_info *usb_list, int list_size)
{
int i = 0;
int res = 0;
HDEVINFO hDevInfo;
SP_DEVINFO_DATA DeviceInfoData = {sizeof(DeviceInfoData)}; // get device class information handle
hDevInfo = SetupDiGetClassDevs(&GUID_DEVINTERFACE_DISK,0, 0, DIGCF_PRESENT|DIGCF_DEVICEINTERFACE);
if (hDevInfo == INVALID_HANDLE_VALUE)
{
res = GetLastError();
return res;
} // enumerute device information
DWORD required_size = 0;
for (i = 0; SetupDiEnumDeviceInfo(hDevInfo, i, &DeviceInfoData); i++)
{
DWORD DataT;
char friendly_name[2046] = {0};
DWORD buffersize = 2046;
DWORD req_bufsize = 2046; // get device friendly name
if (!SetupDiGetDeviceRegistryPropertyA(hDevInfo, &DeviceInfoData, SPDRP_FRIENDLYNAME, &DataT, (LPBYTE)friendly_name, buffersize, &req_bufsize))
{
continue;
}
if (strstr(friendly_name, "USB") == 0)
{
continue;
} int index = 0;
SP_DEVICE_INTERFACE_DATA did = {sizeof(did)};
PSP_DEVICE_INTERFACE_DETAIL_DATA pdd = NULL; while(1)
{
// get device interface data
if (!SetupDiEnumDeviceInterfaces(hDevInfo, &DeviceInfoData, &GUID_DEVINTERFACE_DISK, index++, &did))
{
res = GetLastError();
if( ERROR_NO_MORE_DEVICES == res || ERROR_NO_MORE_ITEMS == res)
break;
} // get device interface detail size
if (!SetupDiGetDeviceInterfaceDetail(hDevInfo, &did, NULL, 0, &required_size, NULL))
{
res = GetLastError();
if(ERROR_INSUFFICIENT_BUFFER == res)
{
pdd = (PSP_DEVICE_INTERFACE_DETAIL_DATA)LocalAlloc(LPTR, required_size);
pdd->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA);
}
else
break;
} // get device interface detail
if (!SetupDiGetDeviceInterfaceDetail(hDevInfo, &did, pdd, required_size, NULL, NULL))
{
res = GetLastError();
LocalFree(pdd);
pdd = NULL;
break;
} // get device number
DWORD bytes_returned = 0;
STORAGE_DEVICE_NUMBER device_num;
HANDLE hDevice = CreateFile(pdd->DevicePath, 0, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);
if (DeviceIoControl(hDevice, IOCTL_STORAGE_GET_DEVICE_NUMBER,
NULL, 0,
&device_num, sizeof(device_num),
&bytes_returned, (LPOVERLAPPED) NULL))
{
for (int usb_index = 0; usb_index < list_size; usb_index++)
{
if (device_num.DeviceNumber == usb_list[usb_index].device_num)
{
strcpy_s(usb_list[usb_index].friendname, friendly_name);
break;
}
}
}
CloseHandle(hDevice);
LocalFree(pdd);
pdd = NULL;
}
} SetupDiDestroyDeviceInfoList(hDevInfo);
return res;
}
3，调用代码：
typedef struct usb_device_info_t
{
char volume;
char friendname[256];
int device_num;
}usb_device_info;
int _tmain(int argc, _TCHAR* argv[])
{
bool bRes = false; usb_device_info usb_list[8];
memset(usb_list, 0, 8*sizeof(usb_device_info));
int usb_cnt = get_usb_device_list(usb_list, 8);
printf("System has %d USB disk.\n", usb_cnt); if (usb_cnt > 0)
{
get_usb_device_friendname(usb_list, usb_cnt);
{
for (int i = 0; i < usb_cnt; i++)
{
printf("%c: %s\n", usb_list[i].volume, usb_list[i].friendname);
}
}
} getchar();
return 1;
}
4，运行结果如下：