/* $Id: look.y,v 1.1 2004/03/30 07:19:17 jmuelmen Exp $ */

%{
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

extern char *look_yytext;

int look_yylex ();
void look_yyerror (const char *s);
void look_gen (double, double, double);

static double Rd;
static double Rv;
static double Rw;

%}

%token RES

%start dac_list

%%

res
	: RES
		{
		     char *rs = strstr(look_yytext, "= ") + 2;
		     double r;
		     *strstr(rs, " ") = 0;
		     r = atof(rs);
		     $$ = (signed int)look_yytext[1];
		     switch (look_yytext[1]) {
		     case 'd':
			  Rd = r;
			  break;
		     case 'v':
			  Rv = r;
			  break;
		     case 'w':
			  Rw = r;
			  break;
		     default:
			  $$ = -1;
			  yyerror("Funny resistor.");
			  break;
		     }
		}
	;

dac
	: res res res
		{
		     if ($1 == -1 || $2 == -1 || $3 == -1) {
			  fprintf(stderr, "Refusing to work with funny"
				  " resistors\n");
			  exit(1);
		     }
		     if ($1 == $2 || $1 == $3 || $2 == $3) {
			  fprintf(stderr, "Refusing to work with funny"
				  " resistors\n");
			  exit(1);
		     }
		     look_gen(Rd, Rv, Rw);
		}
	;

dac_list
	:
	| dac dac_list
	;

%%


void look_yyerror (const char *s)
{
     fprintf(stderr, "%s\n", s);
}