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