/*
	This a toy program to examine serial port
	and may be useful to identify your mouse type
	
	usage example:
	xdcom b9600 pn l8 c0
	
	-Kenar-
*/


#include <u.h>
#include <libc.h>

enum{
	TIMEOUT = 5000,
};

void err(char *s){
	fprint(2, "%s\n", s);
	exits(s);
}


void
usage(void)
{       print("usage example: com  b9600 pn l8 c0\n");
        exits("usage");
}

int tputs(int fd, char *s){
	int n;
	alarm(TIMEOUT);
	n = write(fd, s, strlen(s));
	alarm(0);
	if(n < 0){
		fprint(2, "%s: timed out in writing %s\n", argv0, s);
		exits("timeout");
	}
	return n;
}


void main(int argc, char *argv[]){
	char *speed = "b9600";
	char *parity = "pn";
	char *length = "l8";
	char *stop = "s1";
	char *comport = "c0";
	char *p;
	int data, ctl, cctl;
	int n, cpid;
	char buf[256];
	
	USED(argc);
	argv0 = *argv++;
	p = *argv++;
	while(p) {
		switch(*p){
		case 'b': speed = p;
			break;
		case 'p': parity = p;
			break;
		case 'l': length = p;
			break;
		case 's': stop = p;
			break;
		case 'c': comport = p;
			break;
		default:
			usage();
		}
		p = *argv++;
	}

	sprint(buf, "/dev/eia%c", comport[1]);
	data = open(buf, ORDWR);
	if(data < 0) err("com port not open");

	sprint(buf, "/dev/eia%cctl", comport[1]);
	ctl = open(buf, ORDWR);
	if(ctl < 0) err("com ctl not open");

	/* set com protocol */
	tputs(ctl, speed);
	tputs(ctl, length);
	tputs(ctl, parity);
	tputs(ctl, stop);

	/* turn to raw mode */
	cctl = open("/dev/consctl", OWRITE);
	if(cctl < 0) err("/dev/consctl not open");
	tputs(cctl, "rawon");
	
	cpid = fork();
	if(cpid == 0){ /* child process */
		int i;
		close(0);
		while((n = read(data, buf, sizeof(buf))) > 0 ) {
			for(i = 0; i < n; i++) print("%.02ux ", (uchar)buf[i]);
			print("\n");
		}
		exits(0);
	}
	/* parent */
	close(1);

	while((n = read(0, buf, sizeof(buf))) > 0){
		if(buf[0] == 0x7f) break;
		write(data, buf, n);
	}
	postnote(PNPROC, cpid, "terminate");
	exits(0);
}