#

/* Unix command for system running under Ersatz-11 PDP-11 simulator to
 * set the console switch register on the simulator; works with DOS
 * device device driver.
 *
 * The -d flag prints debugging info.
 */

/* DOS device information */

#include "/usr/sys/dos.h"


struct	hsterrs	{	int	ds_errno;
			char	*ds_errstr;
		};

int	*herrtbl[] {
	RC_NXM, "Bus timeout",
	RC_NOT, "File or directory does not exist",
	RC_INVH, "Invalid handle",
	RC_INSM, "Insufficient memory",
	RC_PERM, "Permission denied",
	RC_FEX, "File exists",
	RC_CROSS, "Cross-device link",
	RC_INV, "Invalid command or argument",
	RC_TOO, "Too many open files",
	RC_NOSPC, "No space left on device",
	RC_RDEAD, "Resource deadlock would occur",
	0, 0 };
	
struct	sargs	{
	char	op;
	char	mode;
	char	*nm;
	int	len;
	}	sargs;

#define	DOSMAXFL	256	/* Maximum file name length */


/* Unix stuff */

extern	int	errno;
extern	char	*sys_errlist[];


/* Command */

#define	SSLEN	11		/* sizeof ("set switch ") */

int	dosdev;

char	ssbuf[DOSMAXFL] "set switch ";

int	dflg;			/* Debugging */



/* 
 */

main(argc, argv)
char **argv;

{	register char	*ifp, *ofp;
	register int	i;
		char	*arg, *octval;
		int	vlen, sval;


	if (argc < 2) {
		printf("setcsw {-d} <octval>\n");
		exit(1);
		}

	argv++;
	for (argc--; (argc > 0); argc--) {
		arg = *argv;
		if (*arg++ != '-')
			break;

		argv++;
		switch (*arg) {

		  case 'd':	dflg++;
				break;

		  default:	printf("Bad flag: %c", *arg);
				exit(1);
		  }
		}


	dosdev = open("/dev/dos", 0);
	if (dosdev < 0)
		serror("Cannot open DOS device");

	if (dflg)
		printf("dosdev file %d\n", dosdev);


	octval = *argv++;
	vlen = strlen(octval);

	ifp = octval;
	ofp = &ssbuf[SSLEN];

	for (i = 0; (i <= vlen); i++)
		*ofp++ = *ifp++;
	
	sargs.op = DC_HOST;
	sargs.nm = &ssbuf[0];
	sargs.len = (vlen + SSLEN);

	if (dflg)
		printf("'%s' %d\n", sargs.nm, sargs.len);
	
	sval = stty(dosdev, &sargs);
	if (sval < 0)
		hsterr("Can't set switch register on emulator");

	close(dosdev);

	exit(0);
}


hsterr(errstr)
char	*errstr;

{	register struct hsterrs	*dp;
		int	gval, hstrc;

	printf("%s\n", errstr);

	gval = gtty(dosdev, &sargs);
	if (gval < 0)
		serror("Can't retrieve host error code");

	hstrc = sargs.op;
	for (dp = &herrtbl[0]; (dp->ds_errno != 0); dp++)
		if (dp->ds_errno == hstrc)
			break;

	if (dp->ds_errno == 0)
		printf("Unknown host error %d\n", hstrc);
	  else
		printf("Host error: %s\n", dp->ds_errstr);

	serror("Unix error");
}


serror(errstr)
char	*errstr;

{       char    *s;

	if (errstr != 0)
		printf("%s: ", errstr);
	
	s = sys_errlist[errno];
	printf("%s\n", s);

	exit(1);
}