args.c

/*
 * UNIX shell
 *
 * S. R. Bourne
 * Bell Telephone Laboratories
 *
 */

#include "defs.h"

extern STRING *copyargs();
static DOLPTR dolh;

CHAR flagadr[10];

CHAR flagchar[] = {
	'x', 'n', 'v', 't', 's', 'i', 'e', 'r', 'k', 'u', 0
};
INT flagval[] = {
	execpr, noexec, readpr, oneflg, stdflg, intflg, errflg, rshflg, keyflg, setflg, 0
};

/* ========	option handling	======== */

INT
options(argc, argv)
STRING *argv;
INT argc;
{
	register STRING cp;
	register STRING *argp = argv;
	register STRING flagc;
	STRING flagp;

	if (argc > 1 && *argp[1] == '-') {
		cp = argp[1];
		flags &= ~(execpr | readpr);
		while (*++cp) {
			flagc = flagchar;

			while (*flagc && *flagc != *cp)
				flagc++;
			if (*cp == *flagc)
				flags |= flagval[flagc - flagchar];
			else if (*cp == 'c' && argc > 2 && comdiv == 0) {
				comdiv = argp[2];
				argp[1] = argp[0];
				argp++;
				argc--;
			} else
				failed(argv[1], badopt);
		}
		argp[1] = argp[0];
		argc--;
	}

	/* set up $- */
	flagc = flagchar;
	flagp = flagadr;
	while (*flagc) {
		if (flags & flagval[flagc - flagchar])
			*flagp++ = *flagc;
		flagc++;
	}
	*flagp++ = 0;

	return argc;
}

VOID
setargs(argi)
STRING argi[];
{
	/* count args */
	register STRING *argp = argi;
	register INT argn = 0;

	while (Rcheat(*argp++) != ENDARGS)
		argn++;

	/* free old ones unless on for loop chain */
	freeargs(dolh);
	dolh = copyargs(argi, argn); /* sets dolv */
	assnum(&dolladr, dolc = argn - 1);
}

freeargs(blk)
DOLPTR blk;
{
	register STRING *argp;
	register DOLPTR argr = 0;
	register DOLPTR argblk;

	if (argblk = blk) {
		argr = argblk->dolnxt;
		if ((--argblk->doluse) == 0) {
			for (argp = argblk->dolarg; Rcheat(*argp) != ENDARGS; argp++)
				free(*argp);
			free(argblk);
		}
	}
	return argr;
}

static STRING*
copyargs(from, n)
STRING from[];
{
	register STRING *np = alloc(sizeof(STRING *) * n + 3 * BYTESPERWORD);
	register STRING *fp = from;
	register STRING *pp = np;

	np->doluse = 1; /* use count */
	np = np->dolarg;
	dolv = np;

	while (n--)
		*np++ = make(*fp++);
	*np++ = ENDARGS;
	return pp;
}

clearup()
{
	/* force `for' $* lists to go away */
	while (argfor = freeargs(argfor));

	/* clean up io files */
	while (pop());
}

DOLPTR
useargs()
{
	if (dolh) {
		dolh->doluse++;
		dolh->dolnxt = argfor;
		return argfor = dolh;
	} else
		return 0;
}