C++访问USB接口

幽灵天

下面是访问 USB 口必备的函数: #include <vcl.h>

#include <dir.h>
#include <setupapi.h>
#include "C:/WINDDK/3790/inc/ddk/w2k/usbdi.h"
#include "C:/WINDDK/3790/inc/ddk/w2k/devioctl.h"
#include <initguid.h>
//---------------------------------------------------------------------------
// 下面必须为驱动程序的 GUID 值, 这里我乱写的数
DEFINE_GUID(USB_DRIVER_GUID, 0x12345678,0xabcd,0x1122,0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00);
//---------------------------------------------------------------------------
HANDLE OpenOneDevice(HDEVINFO hDvcInfo, PSP_INTERFACE_DEVICE_DATA DvcInfoData, char *sDevNameBuf)
{
HANDLE hOut = INVALID_HANDLE_value;

ULONG iReqLen = 0;
SetupDiGetInterfaceDeviceDetail(hDvcInfo, DvcInfoData, NULL, 0, &iReqLen, NULL);

ULONG iDevDataLen = iReqLen; //sizeof(SP_FNCLASS_DEVICE_DATA) + 512;
PSP_INTERFACE_DEVICE_DETAIL_DATA pDevData = (PSP_INTERFACE_DEVICE_DETAIL_DATA)malloc(iDevDataLen);

pDevData->cbSize = sizeof(SP_INTERFACE_DEVICE_DETAIL_DATA);
if(SetupDiGetInterfaceDeviceDetail(hDvcInfo, DvcInfoData, pDevData, iDevDataLen, &iReqLen, NULL))
{
strcpy(sDevNameBuf, pDevData->DevicePath);
hOut = CreateFile(pDevData->DevicePath, GENERIC_READ|GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);
}

free(pDevData);
return hOut;
}
//---------------------------------------------------------------------------
HANDLE OpenUsbDevice(const GUID *pGuid, char *sDevNameBuf)
{
HANDLE hOut = INVALID_HANDLE_value;

HDEVINFO hDevInfo = SetupDiGetClassDevs(pGuid, NULL, NULL, DIGCF_PRESENT|DIGCF_INTERFACEDEVICE);

SP_INTERFACE_DEVICE_DATA deviceInfoData;
deviceInfoData.cbSize = sizeof (SP_INTERFACE_DEVICE_DATA);

ULONG nGuessCount = MAXLONG;
for(ULONG iDevIndex=0; iDevIndex<nGuessCount; iDevIndex++)
{
if(SetupDiEnumDeviceInterfaces(hDevInfo, 0, pGuid, iDevIndex, &deviceInfoData))
{
if((hOut=OpenOneDevice(hDevInfo, &deviceInfoData, sDevNameBuf)) != INVALID_HANDLE_value)
break;
}
else if(GetLastError() == ERROR_NO_MORE_ITEMS) //No more items
{
break;
}
}
SetupDiDestroyDeviceInfoList(hDevInfo);
return hOut;
}
//---------------------------------------------------------------------------
bool GetUsbDeviceFileName(const GUID *pGuid, char *sDevNameBuf)
{
HANDLE hDev = OpenUsbDevice(pGuid, sDevNameBuf);
if(hDev != INVALID_HANDLE_value)
{
CloseHandle(hDev);
return true;
}
return false;
}
//---------------------------------------------------------------------------
HANDLE OpenMyDevice()
{
char DeviceName[MAXPATH] = "";
return OpenUsbDevice(&USB_DRIVER_GUID, DeviceName);
}
//---------------------------------------------------------------------------
HANDLE OpenMyDevPipe(const char *PipeName)
{
char DeviceName[MAXPATH] = "";
if(GetUsbDeviceFileName(&USB_DRIVER_GUID, DeviceName))
{
strcat(DeviceName,"\\");
strcat(DeviceName,PipeName);
return CreateFile(DeviceName, GENERIC_WRITE|GENERIC_READ, FILE_SHARE_WRITE|FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
}
return INVALID_HANDLE_value;
}
//---------------------------------------------------------------------------
有了上面的函数就可以访问 USB 口了://打开 USB 口读写, 由驱动程序的 Pipe 名确定

HANDLE hPipe = OpenMyDevPipe("MyPipe1"); //驱动程序里面的 Pipe 名, 对应访问某个端点的 I/O, 这里我乱写的, 需要与驱动一致
if(hPipe != INVALID_HANDLE_value) //打开 Pipe 成功
{
ReadFile(hPipe, Buffer, BufSize, &nBytesRead, NULL); //从 hPipe 里读取数据到 Buffer 里
//WriteFile(hPipe, Buffer, BytesToWrite, &nBytesWritten, NULL); //把 Buffer 里面的 BytesToWrite 字节写入 hPipe
CloseHandle(hPipe);
}

//使用 DeviceIoControl 访问 USB 设备

HANDLE hDevice = OpenMyDevice();
if(hDevice != INVALID_HANDLE_value) //打开设备成功
{
//这些 DeviceIoControl 功能