1/*
2 * extend.c --- extend a file so that it has at least a specified
3 * 	number of blocks.
4 *
5 * Copyright (C) 1993, 1994, 1995 Theodore Ts'o.
6 *
7 * This file may be redistributed under the terms of the GNU Public
8 * License.
9 */
10
11#include "config.h"
12#include <stdio.h>
13#include <unistd.h>
14#include <stdlib.h>
15#include <string.h>
16#include <sys/types.h>
17#include <fcntl.h>
18#include "../misc/nls-enable.h"
19
20static void usage(char *progname)
21{
22	fprintf(stderr, _("%s: %s filename nblocks blocksize\n"),
23		progname, progname);
24	exit(1);
25}
26
27
28int main(int argc, char **argv)
29{
30	char	*filename;
31	int	nblocks, blocksize;
32	int	fd;
33	char	*block;
34	int	ret;
35
36	if (argc != 4)
37		usage(argv[0]);
38
39	filename = argv[1];
40	nblocks = strtoul(argv[2], 0, 0) - 1;
41	blocksize = strtoul(argv[3], 0, 0);
42
43	if (nblocks < 0) {
44		fprintf(stderr, _("Illegal number of blocks!\n"));
45		exit(1);
46	}
47
48	block = malloc(blocksize);
49	if (block == 0) {
50		fprintf(stderr, _("Couldn't allocate block buffer (size=%d)\n"),
51			blocksize);
52		exit(1);
53	}
54	memset(block, 0, blocksize);
55
56	fd = open(filename, O_RDWR);
57	if (fd < 0) {
58		perror(filename);
59		exit(1);
60	}
61	ret = lseek(fd, nblocks*blocksize, SEEK_SET);
62	if (ret < 0) {
63		perror("lseek");
64		exit(1);
65	}
66	ret = read(fd, block, blocksize);
67	if (ret < 0) {
68		perror("read");
69		exit(1);
70	}
71	ret = lseek(fd, nblocks*blocksize, SEEK_SET);
72	if (ret < 0) {
73		perror("lseek #2");
74		exit(1);
75	}
76	ret = write(fd, block, blocksize);
77	if (ret < 0) {
78		perror("read");
79		exit(1);
80	}
81	exit(0);
82}
83