xref: /freebsd/tests/sys/cddl/zfs/bin/largest_file.c (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
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 #include "file_common.h"
29 #include <sys/param.h>
30 #include <signal.h>
31 #include <stdio.h>
32 
33 /*
34  * --------------------------------------------------------------
35  *
36  *	Assertion:
37  *		The last byte of the largest file size can be
38  *		accessed without any errors.  Also, the writing
39  *		beyond the last byte of the largest file size
40  *		will produce an errno of EFBIG.
41  *
42  * --------------------------------------------------------------
43  *	If the write() system call below returns a "1",
44  *	then the last byte can be accessed.
45  * --------------------------------------------------------------
46  */
47 static void	sigxfsz(int);
48 static void	usage(char *);
49 
50 int
51 main(int argc, char **argv)
52 {
53 	int		fd = 0;
54 	off_t		offset = (OFF_MAX - 1);
55 	off_t		lseek_ret = 0;
56 	int		write_ret = 0;
57 	int		err = 0;
58 	char		mybuf[5];
59 	char		*testfile;
60 
61 	if (argc != 2) {
62 		usage(argv[0]);
63 	}
64 
65 	(void) sigset(SIGXFSZ, sigxfsz);
66 
67 	testfile = strdup(argv[1]);
68 
69 	fd = open(testfile, O_CREAT | O_RDWR);
70 	if (fd < 0) {
71 		perror("Failed to create testfile");
72 		err = errno;
73 		goto out;
74 	}
75 
76 	lseek_ret = lseek(fd, offset, SEEK_SET);
77 	if (lseek_ret < 0) {
78 		perror("Failed to seek to end of testfile");
79 		err = errno;
80 		goto out;
81 	}
82 
83 	write_ret = write(fd, mybuf, 1);
84 	if (write_ret < 0) {
85 		perror("Failed to write to end of file");
86 		err = errno;
87 		goto out;
88 	}
89 
90 	offset = 0;
91 	lseek_ret = lseek(fd, offset, SEEK_CUR);
92 	if (lseek_ret < 0) {
93 		perror("Failed to seek to end of file");
94 		err = errno;
95 		goto out;
96 	}
97 
98 	write_ret = write(fd, mybuf, 1);
99 	if (write_ret < 0) {
100 		if (errno == EFBIG) {
101 			(void) printf("write errno=EFBIG: success\n");
102 			err = 0;
103 		} else {
104 			perror("Did not receive EFBIG");
105 			err = errno;
106 		}
107 	} else {
108 		(void) printf("write completed successfully, test failed\n");
109 		err = 1;
110 	}
111 
112 out:
113 	(void) unlink(testfile);
114 	free(testfile);
115 	return (err);
116 }
117 
118 static void
119 usage(char *name)
120 {
121 	(void) printf("%s <testfile>\n", name);
122 	exit(1);
123 }
124 
125 /* ARGSUSED */
126 static void
127 sigxfsz(int signo)
128 {
129 	(void) printf("\nlargest_file: sigxfsz() caught SIGXFSZ\n");
130 }
131