gpsutil.cpp

很好的GPS应用源码

	wsprintf(szBufW, _T("%d度%d分%f秒(%c) %f"), n1,n2,d3,dire_longitude, longX);
	::SendMessage(subhWnd, WM_SETTEXT, 0, (LPARAM)(LPCTSTR)(szBufW));

	subhWnd = GetDlgItem(hWnd, IDC_VELOCITY); 
	wsprintf(szBufW, _T("%f"), velocity);
	::SendMessage(subhWnd, WM_SETTEXT, 0, (LPARAM)(LPCTSTR)(szBufW));

	subhWnd = GetDlgItem(hWnd, IDC_DIRECTION); 
	wsprintf(szBufW, _T("%f"), direction);
	::SendMessage(subhWnd, WM_SETTEXT, 0, (LPARAM)(LPCTSTR)(szBufW));

	//刷新星的位置图
	RECT rt;
	POINT pt;
	int r;
	subhWnd = GetDlgItem(hWnd, IDC_MAP);
	GetWindowRect(subhWnd, &rt);
	pt.x = (rt.left + rt.right)/2;
	pt.y = (rt.top + rt.bottom)/2;
	r = abs(rt.right - rt.left);
	ScreenToClient(hWnd, &pt);

	rt.left = pt.x - r/2 - 10;
	rt.top = pt.y - r/2 - 10;
	rt.right = pt.x + r/2 + 10;
	rt.bottom = pt.y + r/2 + 10;

	InvalidateRect(hWnd, &rt, false);

	return ;	
}

//启动GPS		
bool GPSStart(HWND hWnd)
{
	if( bGPSStart ) return( true );

	wchar_t szPort[15];
	DCB dcb;

	pIDComDev = INVALID_HANDLE_VALUE;
	wsprintf( szPort, _T("COM%d:"), nPort );
	pIDComDev = CreateFile( szPort,//指向端口名的Pointer 
		GENERIC_READ | GENERIC_WRITE,//允许读和写
		0,//独占方式（共享模式）
		NULL,
		OPEN_EXISTING,//打开而不是创建（创建方式）
		0,	//FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED,//重叠方式（文件属性和标志）
		NULL 
		);

	if( pIDComDev == INVALID_HANDLE_VALUE)
	{
		DWORD dwError=GetLastError();
		::MessageBox(0,_T("打开端口出错！请确定端口设备的使用情况后关闭重试."),_T("错误!"),MB_OK );
		return false;
	}

	SetCommMask(pIDComDev, EV_RXCHAR); 
	PurgeComm(pIDComDev,PURGE_TXABORT|PURGE_RXABORT|PURGE_TXCLEAR|PURGE_RXCLEAR); 

	COMMTIMEOUTS CommTimeOuts;
	GetCommTimeouts (szPort, &CommTimeOuts);

    CommTimeOuts.ReadIntervalTimeout = 0xFFFFFFFF;  
    CommTimeOuts.ReadTotalTimeoutMultiplier = 0;  
    CommTimeOuts.ReadTotalTimeoutConstant = 1000;    
    CommTimeOuts.WriteTotalTimeoutMultiplier = 0;  
    CommTimeOuts.WriteTotalTimeoutConstant = 1000;    

	if(!SetCommTimeouts( pIDComDev, &CommTimeOuts ))
	{
		//could not creatthe read thread;
		::MessageBox (NULL,_T("不能设置延时参数"),_T("错误!"),MB_OK);
		CloseHandle( pIDComDev );
		return false;
	}

	/////////////端口设置
	dcb.DCBlength = sizeof( DCB );
	//获得端口设置信息
	GetCommState( pIDComDev, &dcb );
	//端口波特率
	dcb.BaudRate = arrayBaud[nBaud];
	dcb.ByteSize = nByteSize;                 // Number of bits/byte, 4-8 
    dcb.Parity = nParity; //NOPARITY; //old 2           // 0-4=no,odd,even,mark,space 
    dcb.StopBits = nStopBits;//	ONESTOPBIT;        // 0,1,2 = 1, 1.5, 2 
    dcb.fOutxDsrFlow = false;         // No DSR output flow control 
    dcb.fDtrControl = DTR_CONTROL_ENABLE; 
    dcb.fOutxCtsFlow = false;         // No CTS output flow control 
    dcb.fRtsControl = RTS_CONTROL_ENABLE; 
    dcb.fOutX = false;                // No XON/XOFF out flow control 
    dcb.fInX = false; //old true                // No XON/XOFF in flow control 
    dcb.fBinary = true;               // Binary mode; no EOF check 
    dcb.fParity = true;               // Enable parity checking 
                                      // DTR flow control type 

	if( !SetCommState( pIDComDev, &dcb )||
		!SetupComm( pIDComDev, 1024, 1024 ))
	{
		DWORD dwError = GetLastError();

		CloseHandle( pIDComDev );
		::MessageBox(0,_T("初始化端口不正确！"),_T("错误!"),MB_OK );
		return( false );
	}

	// 创建一个读端口线程.
	pReadThread = CreateThread (NULL, 0,
		(LPTHREAD_START_ROUTINE)PortReadThread, 
		hWnd, 0, &dwThreadID);

	if(pReadThread == NULL)
	{
		::MessageBox (NULL, _T("不能创建一个读端口线程"), _T("错误!"), MB_OK);
		CloseHandle( pIDComDev );
		return (false);
	}

	return( true );
}

//停止GPS
bool GPSEnd()
{
	if( !bGPSStart )
		return (true);

	if(pReadThread != NULL)
	{
		CloseHandle(pReadThread);
		pReadThread = NULL;
	}

	// Close the communication port.
	SetCommMask(pIDComDev,0); 
	EscapeCommFunction(pIDComDev,CLRDTR); 
	PurgeComm(pIDComDev,PURGE_TXABORT|PURGE_RXABORT| PURGE_TXCLEAR|PURGE_RXCLEAR); 

	if (!CloseHandle (pIDComDev))
	{
		::MessageBox (NULL,_T("关闭端口错误"),_T("错误!"),MB_OK);
		return (false);
	}

	return( true );  
}

//读数线程
LRESULT CALLBACK PortReadThread(HWND hWnd)
{
	//发启动信号"!"
/*	DWORD dwNumByteWritten;
	char star[256];
	sprintf(star,("ASTRAL\r\n"));
	if(!WriteFile(pIDComDev, &star, strlen(star), &dwNumByteWritten, NULL))
	{
		::MessageBox (NULL,_T("发送启动命令 - 1失败！!"),_T("RIGHT"),MB_OK);
		return false;
	}

	sprintf(star,("$PRWIILOG,RMC,A,T,2,0\r\n"));
	if(!WriteFile(pIDComDev, &star, strlen(star), &dwNumByteWritten, NULL))
	{
		::MessageBox (NULL,_T("发送启动命令 - 2失败！!"),_T("RIGHT"),MB_OK);
		return false;
	}

	sprintf(star,("$PRWIILOG,GSA,A,T,5,0\r\n"));
	if(!WriteFile(pIDComDev, &star, strlen(star), &dwNumByteWritten, NULL))
	{
		::MessageBox (NULL,_T("发送启动命令 - 3失败！!"),_T("RIGHT"),MB_OK);
		return false;
	}

	sprintf(star,("$PRWIILOG,GSV,A,T,6,0\r\n"));
	if(!WriteFile(pIDComDev, &star, strlen(star), &dwNumByteWritten, NULL))
	{
		::MessageBox (NULL,_T("发送启动命令 - 4失败！!"),_T("RIGHT"),MB_OK);
		return false;
	}

	sprintf(star,("$PRWIILOG,GGA,A,T,4,0\r\n"));
	if(!WriteFile(pIDComDev, &star, strlen(star), &dwNumByteWritten, NULL))
	{
		::MessageBox (NULL,_T("发送启动命令 - 5失败！!"),_T("RIGHT"),MB_OK);
		return false;
	}

	sprintf(star,("$PRWIILOG,ZCH,V,,,\r\n"));
	if(!WriteFile(pIDComDev, &star, strlen(star), &dwNumByteWritten, NULL))
	{
		::MessageBox (NULL,_T("发送启动命令 - 6失败！!"),_T("RIGHT"),MB_OK);
		return false;
	}
*/

// 指定监视的端口事件
	DWORD dwCommModemStatus, dwBytesTransferred; 
	char ReadBuff[MAX_ONEREAD];
	memset(ReadBuff, 0, MAX_ONEREAD);

	SetCommMask (pIDComDev, EV_RXCHAR );
	while (pIDComDev!= INVALID_HANDLE_VALUE)
	{
		// 等待端口事件
		WaitCommEvent (pIDComDev, &dwCommModemStatus, 0);

		// 重新指定监视的端口事件
		SetCommMask (pIDComDev, EV_RXCHAR );

		if (dwCommModemStatus & EV_RXCHAR) 
		{
			// Read the data from the serial port.
			ReadFile (pIDComDev, ReadBuff, MAX_ONEREAD, &dwBytesTransferred, 0);

			// Display the data read.
			if (dwBytesTransferred >= 1)
			{
				// 处理收到的字符
				ReadBuff[dwBytesTransferred] = '\0';
				GPSReadInfo(ReadBuff);

				/*RECT rt;
				GetClientRect(hWnd, &rt);
				InvalidateRect(hWnd, &rt, true);*/
			}
		}
	}

	return true;
}

//读入一段信息后，处理
void GPSReadInfo(char *sMessage)
{
	if(sMessage != NULL)
	{
		if(strlen(sReadBuff) + strlen(sMessage) >= 5*MAX_LENGTH-10)
		{
			strcpy(sReadBuff, "");
		}
		strcat(sReadBuff, sMessage);

		ParseReadBuffer(sReadBuff);
    }
}

//解析读入的缓冲
void ParseReadBuffer(char *sBuff)
{
	if(strlen(sBuff) < 1)return;

	int nlen;
	int nstart, nend;
	int i;

	nlen = strlen(sBuff);
	nstart = 0;
	nend = 0;
	i = 1;
	//从第一个开始,这样保证当开始有'$'符号时，前面可以解析成一个字符串
	while(*(sBuff+i) != '\0')
	{
		if(*(sBuff+i) == '$')
		{
			//获取上一个并解析
			nend = i;
			if(nend-nstart > MAX_LENGTH)
			{
				strcpy(sBuff, "");
				return ;
			}
			else
			{
				memcpy(sSentence, sBuff+nstart, nend-nstart);
				sSentence[nend-nstart] = '\0';
				ParseSentence(sSentence);
			}

			nstart = i;
		}

		i++;
	}

	if(nstart != 0)
	{
		memmove(sBuff, sBuff+nstart, nlen - nstart);
		sBuff[nlen - nstart] = 0;
	}
	return ;

}

//根据开始字符判断类型
int SortSentence(char *sBuff)
{
	if(strlen(sBuff) < 1)return START_UNKNOW;
	if(sBuff[0] != '$' ) return START_UNKNOW;

	if(strstr(sBuff, "$GPGGA") != NULL)
	{
		return START_GPGGA;
	}
	else if(strstr(sBuff, "$GPGSA") != NULL)
	{
		return START_GPGSA;
	}
	else if(strstr(sBuff, "$GPGSV") != NULL)
	{
		return START_GPGSV;
	}
	else if(strstr(sBuff, "$GPRMC") != NULL)
	{
		return START_GPRMC;
	}

	return START_UNKNOW;
}

//根据类型解析出值
//如果解析正确，放回true, 否则false
BOOL ParseSentence(char *sBuff)
{
	BOOL bRtn;
	//首先判断格式的类型
	int type = SortSentence(sBuff);

	//根据不同类型，来解析值
	switch(type)
	{
	case START_GPGGA:
		bRtn = ParseGPGGA(sBuff);
		if(bRtn)
		{
			// 位置改变
			if (GPSMapWnd != NULL)
			{
				SendMessage(GPSMapWnd, GPSPOS_CHANGED,0,0);
			}
		}
		break;
	case START_GPGSA:
		bRtn = ParseGPGSA(sBuff);
		if(bRtn)
		{
			// 活动卫星改变
		}
		break;

	case START_GPGSV:
		bRtn = ParseGPGSV(sBuff);
		if(bRtn)
		{
			// 可视卫星改变
		}
		break;

	case START_GPRMC:
		bRtn = ParseGPRMC(sBuff);
		if(bRtn)
		{
			// 时间、速度、方向改变，
			if (GPSMapWnd != NULL)
			{
				SendMessage(GPSMapWnd, GPSSPEED_CHANGED,0,0);
			}
		}

		break;
	case START_UNKNOW :
		bRtn = false;
	default:
		bRtn = false;
		break;
	}

	if(bRtn)
	{
		if(GPSStatushWnd != NULL)
		{
			SendMessage(GPSStatushWnd, GPSINFO_CHANGED,0,0);
		}
	}
	return bRtn;
}

//解析GPGGA
BOOL ParseGPGGA(char *sBuff)
{
	if(strlen(sBuff) < 1)return false;

	int nstart, nend;
	int i;
	int index;
	int num;

	nstart = -1;
	nend = 0;
	i = 1;
	index = 0;

	//从第一个开始,这样保证但开始有'$'符号时，前面可以解析成一个字符串
	while(*(sBuff+i) != '\0')
	{
		if(*(sBuff+i) == ',')
		{
			nend = i;
			if(nend == nstart)
			{
				strcpy(sTempBuff, "");
			}
			else
			{
				nstart++;  //保证除掉','
				memcpy(sTempBuff, sBuff+nstart, nend-nstart);
				sTempBuff[nend-nstart] = '\0';
			}
			nstart = i;

			//获取上一个解析
			switch(index){
			case 1:
				//时间
				num =atoi(sTempBuff);
				nhour = num/10000;
				nminute = (num-nhour*10000)/100;
				nsecond = num-nhour*10000-nminute*100;
				break;
			case 2:
				//纬度
				latitude = atof(sTempBuff);
				break;
			case 3:
				//为北纬或南纬
				dire_latitude = sTempBuff[0];
				break;
			case 4:
				//经度
				longitude = atof(sTempBuff);
				break;
			case 5:
				//东经或西经
				dire_longitude = sTempBuff[0];
				break;
			case 6:
				//是否已定位
				available = atoi(sTempBuff);
			default: