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 /*
32  * Copyright (c) 2018, Joyent, Inc.
33  */
34 
35 #include "../file_common.h"
36 
37 /*
38  * Create a file with assigned size and then free the specified
39  * section of the file
40  */
41 
42 static void usage(char *progname);
43 
44 static void
usage(char * progname)45 usage(char *progname)
46 {
47 	(void) fprintf(stderr,
48 	    "usage: %s [-l filesize] [-s start-offset]"
49 	    "[-n section-len] filename\n", progname);
50 	exit(1);
51 }
52 
53 int
main(int argc,char * argv[])54 main(int argc, char *argv[])
55 {
56 	char *filename = NULL;
57 	char *buf;
58 	size_t filesize = 0;
59 	off_t start_off = 0;
60 	off_t off_len = 0;
61 	int  fd, ch;
62 	struct flock fl;
63 	mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
64 
65 	while ((ch = getopt(argc, argv, "l:s:n:")) != EOF) {
66 		switch (ch) {
67 		case 'l':
68 			filesize = atoll(optarg);
69 			break;
70 		case 's':
71 			start_off = atoll(optarg);
72 			break;
73 		case 'n':
74 			off_len = atoll(optarg);
75 			break;
76 		default:
77 			usage(argv[0]);
78 			break;
79 		}
80 	}
81 
82 	if (optind == argc - 1)
83 		filename = argv[optind];
84 	else
85 		usage(argv[0]);
86 
87 	buf = (char *)malloc(filesize);
88 
89 	if ((fd = open(filename, O_RDWR | O_CREAT | O_TRUNC, mode)) < 0) {
90 		perror("open");
91 		free(buf);
92 		return (1);
93 	}
94 	if (write(fd, buf, filesize) < filesize) {
95 		perror("write");
96 		free(buf);
97 		return (1);
98 	}
99 	fl.l_whence = SEEK_SET;
100 	fl.l_start = start_off;
101 	fl.l_len = off_len;
102 	if (fcntl(fd, F_FREESP, &fl) != 0) {
103 		perror("fcntl");
104 		free(buf);
105 		return (1);
106 	}
107 
108 	free(buf);
109 	return (0);
110 }
111