usb1.txt

C++ Builder 访问 USB 口的方法

#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;
}
//---------------------------------------------------------------------------