#include <ctype.h>
#include <string.h>
#include <strings.h>
#include <stdio.h>
#include <stdlib.h>
#include "struct.h"

extern char *infnames[2];
extern struct pin_info *database;

#define	MAX_FIELDS	2

static int pass;
static FILE *inf;
static char linebuf[512];
static int lineno;
static char *fields[MAX_FIELDS];
static unsigned nfields;

static void
parse_into_fields()
{
	char *cp;

	nfields = 0;
	for (cp = linebuf; ; ) {
		while (isspace(*cp))
			cp++;
		if (*cp == '\0' || *cp == '#')
			break;
		if (nfields >= MAX_FIELDS) {
			fprintf(stderr, "%s line %d: too many fields\n",
				infnames[pass], lineno);
			exit(1);
		}
		fields[nfields++] = cp;
		while (*cp && !isspace(*cp))
			cp++;
		if (*cp)
			*cp++ = '\0';
	}
}

static void
existing_pin(p, netname)
	struct pin_info *p;
	char *netname;
{
	char *dp;

	if (p->netnames[pass]) {
		fprintf(stderr, "%s line %d: multiple nets to pin %s\n",
			infnames[pass], lineno, p->pin_name);
		exit(1);
	}
	dp = malloc(strlen(netname) + 1);
	if (!dp) {
		perror("malloc");
		exit(1);
	}
	strcpy(dp, netname);
	p->netnames[pass] = dp;
}

static void
process_connect(netname, pinname)
	char *netname, *pinname;
{
	struct pin_info *p, **pp;
	char *dp;

	for (pp = &database; p = *pp; pp = &p->next) {
		if (!strcmp(p->pin_name, pinname)) {
			existing_pin(p, netname);
			return;
		}
	}
	p = malloc(sizeof(struct pin_info) + strlen(netname) + strlen(pinname)
			+ 2);
	if (!p) {
		perror("malloc");
		exit(1);
	}
	bzero(p, sizeof(struct pin_info));
	dp = (char *)(p + 1);
	p->pin_name = dp;
	strcpy(dp, pinname);
	dp += strlen(pinname) + 1;
	p->netnames[pass] = dp;
	strcpy(dp, netname);
	*pp = p;
}

static void
process_line()
{
	parse_into_fields();
	if (!nfields)
		return;
	if (nfields != 2) {
		fprintf(stderr, "%s line %d: expected 2 fields\n",
			infnames[pass], lineno);
		exit(1);
	}
	process_connect(fields[0], fields[1]);
}

read_pass(pass_no)
{
	pass = pass_no;
	inf = fopen(infnames[pass], "r");
	if (!inf) {
		perror(infnames[pass]);
		exit(1);
	}
	lineno = 0;
	while (fgets(linebuf, sizeof linebuf, inf)) {
		lineno++;
		process_line();
	}
	fclose(inf);
	return 0;
}