vxdinp.c

来自「MATLAB扩展编程by 孙永康.ZIP.有需要的朋友请来下载.」· C语言 代码 · 共 50 行

#include "mex.h"
#include <windows.h>
#include <winioctl.h>

#define MEXHARD_INP     CTL_CODE(FILE_DEVICE_UNKNOWN, 1, METHOD_NEITHER, FILE_ANY_ACCESS)
#define MEXHARD_OUTP    CTL_CODE(FILE_DEVICE_UNKNOWN, 2, METHOD_NEITHER, FILE_ANY_ACCESS)

HANDLE		hDevice;

void mexFunction( int nlhs, mxArray *plhs[],
				  int nrhs, const mxArray*prhs[] )
{
	unsigned short port;		// 端口号
	unsigned short byte;		// 端口数据
	DWORD	 cbBytesReturned;	// 返回字节数
	double   *ptr;

	if (nrhs != 1)
		mexErrMsgTxt("Need one parameter\n");

	if (!mxIsNumeric(prhs[0]))
		mexErrMsgTxt("Port should be numeric\n");

	// 获取端口号
	ptr  = mxGetPr(prhs[0]);
	port = (unsigned short) (*ptr);

	// 动态加载VxD。VxD文件必须在当前目录或系统目录
	// CreateFile认为以字符串"\\.\"开始的文件名为动态加载VxD
	hDevice = CreateFile("\\\\.\\MEXHARD.VXD", 0,0,0,
                        CREATE_NEW, FILE_FLAG_DELETE_ON_CLOSE, 0);

	if (hDevice == INVALID_HANDLE_VALUE)
		mexErrMsgTxt("Cannot open driver\n");

	//端口读操作
	DeviceIoControl(hDevice, MEXHARD_INP,
					&port, sizeof(unsigned short),
					&byte, sizeof(unsigned short),
					&cbBytesReturned, NULL);

	// VxD卸载
	CloseHandle(hDevice);

	//返回参数
	plhs[0] = mxCreateDoubleMatrix(1, 1, mxREAL);
	ptr     = mxGetPr(plhs[0]);
	*ptr    = (double)byte;
}