2 * Copyright 2010 Google Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
16 * compute rom checksum byte
23 #include <sys/types.h>
25 #define MAX_SIZE 65536
26 unsigned char buf[MAX_SIZE];
28 int main(int argc, char **argv)
35 fprintf(stderr, "usage: %s filename\n", argv[0]);
38 if ((fd = open(argv[1], O_RDWR)) < 0) {
42 if ((fsize = read(fd, buf, MAX_SIZE)) < 0) {
46 if (fsize >= MAX_SIZE && read(fd, &buf[MAX_SIZE - 1], 1) > 0) {
47 fprintf(stderr, "FAIL: %s is larger than %d bytes\n", argv[1], MAX_SIZE);
50 i = fsize - 2048 * (fsize / 2048);
52 fprintf(stderr, "FAIL: %s is %zd bytes, need 2K pad-1\n", argv[1], fsize);
55 for (i = sum = 0; i < fsize; i++) {
62 fprintf(stderr, "%s: sum = 0x%02x, wrote byte 0x%02x\n", argv[1], sum, csum);