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/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* SPDX-License-Identifier: MPL-2.0
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include <isc/print.h>
#define USAGE "usage: gencheck <filename>\n"
static int
check(const char *buf, ssize_t count, size_t *start) {
const char chars[] = "abcdefghijklmnopqrstuvwxyz0123456789";
ssize_t i;
for (i = 0; i < count; i++, *start = (*start + 1) % (sizeof(chars) - 1))
{
/* Just ignore the trailing newline */
if (buf[i] == '\n') {
continue;
}
if (buf[i] != chars[*start]) {
return (0);
}
}
return (1);
}
int
main(int argc, char **argv) {
int ret;
int fd;
ssize_t count;
char buf[1024];
size_t start;
size_t length;
ret = EXIT_FAILURE;
fd = -1;
length = 0;
if (argc != 2) {
fprintf(stderr, USAGE);
goto out;
}
fd = open(argv[1], O_RDONLY);
if (fd == -1) {
goto out;
}
start = 0;
while ((count = read(fd, buf, sizeof(buf))) != 0) {
if (count < 0) {
goto out;
}
if (!check(buf, count, &start)) {
goto out;
}
length += count;
}
ret = EXIT_SUCCESS;
out:
printf("%lu\n", (unsigned long)length);
if (fd != -1) {
close(fd);
}
return (ret);
}
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