#include <modbus.h>#include <signal.h>int Mb_device;				/* device tu use */int Mbm_Pid_Child;		/* PID child used to read the slave answer */int Mbm_Pid_Sleep;		/* PID use to wait the end of the timeout */byte *Mbm_result;			/* byte readed on the serial port : answer of the slave *//************************************************************************************		Mbm_get_data : thread reading data on the serial port*************************************************************************************input :-------len	:	number of data to read;no output************************************************************************************/void Mbm_get_data(int *len ){	int i;	byte read_data;	Mbm_Pid_Child=getpid();		if (Mb_verbose)			fprintf(stderr,"starting receiving data, total length : %d \n",*len);	for(i=0;i<(*len);i++)	{		/* read data */		read(Mb_device,&read_data,1);		/* store data to the slave answer packet */		Mbm_result[i]=read_data;				/* call the pointer function if exist */		if(Mb_ptr_rcv_data!=NULL)			(*Mb_ptr_rcv_data)(read_data);		if (Mb_verbose)			fprintf(stderr,"receiving byte :0x%x %d (%d)\n",read_data,read_data,Mbm_result[i]);	}	if (Mb_verbose)		fprintf(stderr,"receiving data done\n");	Mbm_Pid_Child=0;}int Csm_get_data(int len, int timeout){	int i;	byte read_data;	time_t t;	if (Mb_verbose)		fprintf(stderr,"in get data\n");		t = (time(NULL) + ((timeout * 2)/1000));	for(i=0;i<(len);i++)	{		if(t < time(NULL))			return(0);		/* read data */		while(read(Mb_device,&read_data,1) == 0){			if(t < time(NULL))				return(0);		}		/* store data to the slave answer packet */		Mbm_result[i]=read_data;				if (Mb_verbose)			fprintf(stderr,"receiving byte :0x%x %d (%d)\n",read_data,read_data,Mbm_result[i]);	  	}	if (Mb_verbose)		fprintf(stderr,"receiving data done\n");	return(1);}/************************************************************************************		Mbm_sleep : thread wait timeout*************************************************************************************input :-------timeout : duduration of the timeout in msno output************************************************************************************/void Mbm_sleep(int *timeout){	Mbm_Pid_Sleep=getpid();	if (Mb_verbose)		fprintf(stderr,"sleeping %d ms\n",*timeout);	usleep(*timeout*1000);	Mbm_Pid_Sleep=0;	if (Mb_verbose)		fprintf(stderr,"Done sleeping %d ms\n",*timeout);}/************************************************************************************		Mbm_send_and_get_result : send data, and wait the answer of the slave*************************************************************************************input :-------trame	  : packet to sendtimeout	: duduration of the timeout in mslong_emit : length of the packet to sendlongueur  : length of the packet to readanswer :--------0			: timeout failure1			: answer ok************************************************************************************/int Mbm_send_and_get_result(byte trame[], int timeout, int long_emit, int longueur){	int i,stat1=-1,stat2=-1;	pthread_t thread1,thread2;	Mbm_result = (unsigned char *) malloc(longueur*sizeof(unsigned char));	/* clean port */	tcflush(Mb_device, TCIFLUSH);	/* create 2 threads for read data and to wait end of timeout*/	pthread_create(&thread2, NULL,(void*)&Mbm_sleep,&timeout);	pthread_detach(thread2);	pthread_create(&thread1, NULL,(void*)&Mbm_get_data,&longueur);	pthread_detach(thread1);	if (Mb_verbose)		fprintf(stderr,"start writing \n");	for(i=0;i<long_emit;i++)	{		/* send data */		write(Mb_device,&trame[i],1);		/* call pointer function if exist */		if(Mb_ptr_snd_data!=NULL)			(*Mb_ptr_snd_data)(trame[i]);	}  if (Mb_verbose)		fprintf(stderr,"write ok\n");	do {		if (Mbm_Pid_Child!=0)			/* kill return 0 if the pid is running or -1 if the pid don't exist */			stat1=0;		else			stat1=-1;		if (Mbm_Pid_Sleep!=0)			stat2=0;		else			stat2=-1;		/* answer of the slave terminate or and of the timeout */		if (stat1==-1 || stat2==-1) 			break;		usleep(timeout);	} while(1); 	if (Mb_verbose)	{		fprintf(stderr,"pid reading %d return %d\n",Mbm_Pid_Child,stat1);		fprintf(stderr,"pid timeout %d return %d\n",Mbm_Pid_Sleep,stat2);	}	/* stop both childs */	Mbm_Pid_Child=0;	Mbm_Pid_Sleep=0;	pthread_cancel(thread1);	pthread_cancel(thread2);	/* error : timeout fealure */	if (stat1==0)	{		free(Mbm_result);		return 0;	}	/* ok : store the answer packet in the data trame */	for (i=0;i<=longueur;i++)		trame[i]=Mbm_result[i];		free(Mbm_result);	return 1;}		int Csm_send_and_get_result(unsigned char trame[], int timeout, int long_emit, int longueur){	int i;	int ret;	Mbm_result = trame;		if (Mb_verbose)		fprintf(stderr,"start writing \n");	for(i=0;i<long_emit;i++)	{		/* send data */		write(Mb_device,&trame[i],1);		/* call pointer function if exist */		if(Mb_ptr_snd_data!=NULL)			(*Mb_ptr_snd_data)(trame[i]);	}  if (Mb_verbose)		fprintf(stderr,"write ok\n");	Mb_tio.c_cc[VMIN]=0;	Mb_tio.c_cc[VTIME]=1;	if (tcsetattr(Mb_device,TCSANOW,&Mb_tio) <0) {		perror("Can't set terminal parameters ");		return 0;	}  	ret = Csm_get_data(longueur, timeout);	Mb_tio.c_cc[VMIN]=1;	Mb_tio.c_cc[VTIME]=0;	if (tcsetattr(Mb_device,TCSANOW,&Mb_tio) <0) {		perror("Can't set terminal parameters ");		return 0 ;	}		return ret;}/************************************************************************************					Mbm_master : comput and send a master packet*************************************************************************************input :-------Mb_trame	  : struct describing the packet to comput						device		: device descriptor						slave 		: slave number to call						function 	: modbus function						address		: address of the slave to read or write						length		: lenght of data to senddata_in	  : data to send to the slavedata_out	  : data to read from the slavetimeout	  : timeout duration in msptrfoncsnd : function to call when master send data (can be NULL if you don't whant to use it)ptrfoncrcv : function to call when master receive data (can be NULL if you don't whant to use it)*************************************************************************************answer :--------0 : OK-1 : unknow modbus function-2 : CRC error in the slave answer-3 : timeout error-4 : answer come from an other slave*************************************************************************************/int Mb_master(Mbm_trame Mbtrame,int data_in[], int data_out[],void *ptrfoncsnd, void *ptrfoncrcv){	int i,longueur,long_emit;	int slave, function, adresse, nbre;	byte trame[256];	Mb_device=Mbtrame.device;	slave=Mbtrame.slave;	function=Mbtrame.function;	adresse=Mbtrame.address;	nbre=Mbtrame.length;	Mb_ptr_snd_data=ptrfoncsnd;	Mb_ptr_rcv_data=ptrfoncrcv;			switch (function)	{		case 0x03:		case 0x04:			/* read n byte */			trame[0]=slave;			trame[1]=function;			trame[2]=adresse>>8;			trame[3]=adresse&0xFF;			trame[4]=nbre>>8;			trame[5]=nbre&0xFF;			/* comput crc */			Mb_calcul_crc(trame,6);			/* comput length of the packet to send */			long_emit=8;			break;				case 0x05: //write a single coil			trame[0]=slave;			trame[1]=function;			trame[2]=adresse>>8;			trame[3]=adresse&0xFF;			trame[4]=data_in[0]>>8;			trame[5]=data_in[0]&0xFF;			/* comput crc */			Mb_calcul_crc(trame,6);			/* comput length of the packet to send */			long_emit=8;			break;					case 0x06:			/* write one byte */			trame[0]=slave;			trame[1]=function;			trame[2]=adresse>>8;			trame[3]=adresse&0xFF;			trame[4]=data_in[0]>>8;			trame[5]=data_in[0]&0xFF;			/* comput crc */			Mb_calcul_crc(trame,6);			/* comput length of the packet to send */			long_emit=8;			break;		case 0x07:			/* read status */			trame[0]=slave;			trame[1]=function;			/* comput crc */			Mb_calcul_crc(trame,2);			/* comput length of the packet to send */			long_emit=4;			break;					case 0x08:			/* line test */			trame[0]=slave;			trame[1]=0x08;			trame[2]=0;			trame[3]=0;			trame[4]=0;			trame[5]=0;			Mb_calcul_crc(trame,6);			/* comput length of the packet to send */			long_emit=8;			break;					case 0x10:			/* write n byte  */			trame[0]=slave;			trame[1]=0x10;			trame[2]=adresse>>8;			trame[3]=adresse&0xFF;			trame[4]=nbre>>8;			trame[5]=nbre&0xFF;			trame[6]=nbre*2;			for (i=0;i<nbre;i++)			{				trame[7+i*2]=data_in[i]>>8;				trame[8+i*2]=data_in[i]&0xFF;			}			/* comput crc */			Mb_calcul_crc(trame,7+nbre*2);			/* comput length of the packet to send */			long_emit=(nbre*2)+9;			break;		default:			return -1;	}	if (Mb_verbose) 	{		fprintf(stderr,"send packet length %d\n",long_emit);		for(i=0;i<long_emit;i++)			fprintf(stderr,"send packet[%d] = %0x\n",i,trame[i]);	}		/* comput length of the slave answer */	switch (function)	{		case 0x03:		case 0x04:			longueur=5+(nbre*2);			break;				case 0x05:		case 0x06:		case 0x08:		case 0x10:		longueur=8;			break;		case 0x07:		longueur=5;			break;		default:			return -1;			break;	}	/* send packet & read answer of the slave		answer is stored in trame[] */	for(i = 0;i < 4; i++){		if(Csm_send_and_get_result(trame,Mbtrame.timeout,long_emit,longueur)){			i = 1;			break;		}	}	if(i != 1) 		return -3;	/* timeout error */  	if (Mb_verbose)	{		fprintf(stderr,"answer :\n");		for(i=0;i<longueur;i++)			fprintf(stderr,"answer packet[%d] = %0x\n",i,trame[i]);	}		if (trame[0]!=slave)		return -4;	/* this is not the right slave */	switch (function)	{		case 0x03:		case 0x04:			/* test received data */			if (trame[1]!=0x03 && trame[1]!=0x04)				return -2;			if (Mb_test_crc(trame,3+(nbre*2)))				return -2;			/* data are ok */			if (Mb_verbose)				fprintf(stderr,"Reader data \n");			for (i=0;i<nbre;i++)			{				data_out[i]=(trame[3+(i*2)]<<8)+trame[4+i*2];				if (Mb_verbose)					fprintf(stderr,"data %d = %0x\n",i,data_out[i]);			}			break;					case 0x05: //write a single coil			/* test received data */			if (trame[1]!=0x05)				return -2;			if (Mb_test_crc(trame,6))				return -2;			/* data are ok */			if (Mb_verbose)				fprintf(stderr,"data stored succesfull !\n");			break;				case 0x06:			/* test received data */			if (trame[1]!=0x06)				return -2;			if (Mb_test_crc(trame,6))				return -2;			/* data are ok */			if (Mb_verbose)				fprintf(stderr,"data stored succesfull !\n");			break;		case 0x07:			/* test received data */			if (trame[1]!=0x07)				return -2;			if (Mb_test_crc(trame,3))				return -2;			/* data are ok */			data_out[0]=trame[2];	/* store status in data_out[0] */			if (Mb_verbose)				fprintf(stderr,"data  = %0x\n",data_out[0]);			break;		case 0x08:			/* test received data */			if (trame[1]!=0x08)				return -2;			if (Mb_test_crc(trame,6))				return -2;			/* data are ok */			if (Mb_verbose)				fprintf(stderr,"Loopback test ok \n");			break;		case 0x10:			/* test received data */			if (trame[1]!=0x10)				return -2;			if (Mb_test_crc(trame,6))				return -2;			/* data are ok */			if (Mb_verbose)				fprintf(stderr,"%d setpoint stored succesfull\n",(trame[4]<<8)+trame[5]);			break;		default:			return -1;			break;	}	return 0;}