#include <sys/types.h>
#include <ctype.h>
#include <string.h>
#include <strings.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <ftdi.h>

unsigned eeprom_size;
u_short eeprom[256];

read_eeprom_common(inf, filename_for_errs)
	FILE *inf;
	char *filename_for_errs;
{
	char linebuf[1024], *cp;
	int lineno, rc;
	unsigned ptr = 0, input_off;

	for (lineno = 1; fgets(linebuf, sizeof linebuf, inf); lineno++) {
		for (cp = linebuf; isspace(*cp); cp++)
			;
		if (*cp == '\0' || *cp == '#')
			continue;
		if (ptr >= 256) {
			fprintf(stderr,
				"%s line %d: maximum EEPROM size exceeded\n",
				filename_for_errs, lineno);
			exit(1);
		}
		rc = sscanf(linebuf, "%x: %hx %hx %hx %hx %hx %hx %hx %hx",
			    &input_off, eeprom + ptr, eeprom + ptr + 1,
			    eeprom + ptr + 2, eeprom + ptr + 3,
			    eeprom + ptr + 4, eeprom + ptr + 5,
			    eeprom + ptr + 6, eeprom + ptr + 7);
		if (rc != 9 || input_off != ptr * 2) {
			fprintf(stderr, "%s line %d: invalid input\n",
				filename_for_errs, lineno);
			exit(1);
		}
		ptr += 8;
	}
	if (ptr != 64 && ptr != 128 && ptr != 256) {
		fprintf(stderr, "%s: not an EEPROM image of recognized size\n",
			filename_for_errs);
		exit(1);
	}
	eeprom_size = ptr;
}

read_eeprom_from_file(filename)
	char *filename;
{
	FILE *inf;

	inf = fopen(filename, "r");
	if (!inf) {
		perror(filename);
		exit(1);
	}
	read_eeprom_common(inf, filename);
	fclose(inf);
}

read_eeprom_from_stdin()
{
	read_eeprom_common(stdin, "stdin");
}

main(argc, argv)
	char **argv;
{
	struct ftdi_context ftdi;
	unsigned n;

	if (argc < 2 || argc > 3) {
		fprintf(stderr, "usage: %s device-selector [eeprom-image]\n",
			argv[0]);
		exit(1);
	}
	if (argv[2])
		read_eeprom_from_file(argv[2]);
	else
		read_eeprom_from_stdin();
	ftdi_init(&ftdi);
	if (ftdi_usb_open_string(&ftdi, argv[1]) < 0) {
		fprintf(stderr, "FTDI USB open failed: %s\n", ftdi.error_str);
		exit(1);
	}
	for (n = 0; n < eeprom_size; n++) {
		if (ftdi_write_eeprom_location(&ftdi, n, eeprom[n]) < 0) {
			fprintf(stderr, "EEPROM write error: %s\n",
				ftdi.error_str);
			exit(1);
		}
	}
	ftdi_usb_close(&ftdi);
	exit(0);
}