Windows下USB磁盘开发系列三：枚举系统中U盘、并获取其设备信息

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：