ack/lang/basic/lib/return.c

#include "lib.h"

#define MAXNESTING 1000

int _gotable[MAXNESTING];
int topstk = 0;

void _gosub(int x)
{
/* administer gosub */
#ifdef DEBUG
	printf("store %d in %d\n", x, topstk);
#endif
	if (topstk == MAXNESTING)
		error(26);
	_gotable[topstk] = x;
	topstk++;
}
int _retstmt(void)
{
/* make sure that a return label index is on top
	  of the stack */
#ifdef DEBUG
	printf("return to %d %d\n", _gotable[topstk - 1], topstk - 1);
#endif
	if (topstk == 0 || topstk == MAXNESTING)
		error(1);
	return (_gotable[--topstk]);
}