1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * Copyright (c) 2012 by Delphix. All rights reserved.
29  */
30 
31 #include "../file_common.h"
32 
33 /*
34  * Create a file with assigned size and then free the specified
35  * section of the file
36  */
37 
38 static void usage(char *progname);
39 
40 static void
41 usage(char *progname)
42 {
43 	(void) fprintf(stderr,
44 	    "usage: %s [-l filesize] [-s start-offset]"
45 	    "[-n section-len] filename\n", progname);
46 	exit(1);
47 }
48 
49 int
50 main(int argc, char *argv[])
51 {
52 	char *filename = NULL;
53 	char *buf;
54 	size_t filesize = 0;
55 	off_t start_off = 0;
56 	off_t off_len = 0;
57 	int  fd, ch;
58 	struct flock fl;
59 	mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
60 
61 	while ((ch = getopt(argc, argv, "l:s:n:")) != EOF) {
62 		switch (ch) {
63 		case 'l':
64 			filesize = atoll(optarg);
65 			break;
66 		case 's':
67 			start_off = atoll(optarg);
68 			break;
69 		case 'n':
70 			off_len = atoll(optarg);
71 			break;
72 		default:
73 			usage(argv[0]);
74 			break;
75 		}
76 	}
77 
78 	if (optind == argc - 1)
79 		filename = argv[optind];
80 	else
81 		usage(argv[0]);
82 
83 	buf = (char *)malloc(filesize);
84 
85 	if ((fd = open(filename, O_RDWR | O_CREAT | O_TRUNC, mode)) < 0) {
86 		perror("open");
87 		return (1);
88 	}
89 	if (write(fd, buf, filesize) < filesize) {
90 		perror("write");
91 		return (1);
92 	}
93 	fl.l_whence = SEEK_SET;
94 	fl.l_start = start_off;
95 	fl.l_len = off_len;
96 	if (fcntl(fd, F_FREESP, &fl) != 0) {
97 		perror("fcntl");
98 		return (1);
99 	}
100 
101 	free(buf);
102 	return (0);
103 }
104