xref: /freebsd/tests/sys/file/ftruncate_test.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * Copyright (c) 2006 Robert N. M. Watson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * Very simple regression test.
29  *
30  * Future tests that might be of interest:
31  *
32  * - Make sure we get EISDIR on a directory.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/event.h>
37 #include <sys/socket.h>
38 #include <sys/stat.h>
39 
40 #include <err.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <inttypes.h>
44 #include <limits.h>
45 #include <stdio.h>
46 #include <unistd.h>
47 
48 /*
49  * Select various potentially interesting lengths at and around power of 2
50  * edges.
51  */
52 static off_t lengths[] = {0, 1, 2, 3, 4, 127, 128, 129, 511, 512, 513, 1023,
53     1024, 1025, 2047, 2048, 2049, 4095, 4096, 4097, 8191, 8192, 8193, 16383,
54     16384, 16385};
55 static int lengths_count = sizeof(lengths) / sizeof(off_t);
56 
57 int
58 main(void)
59 {
60 	int error, fd, fds[2], i, read_only_fd;
61 	char path[] = "ftruncate_file";
62 	struct stat sb;
63 	ssize_t size;
64 	off_t len;
65 	char ch;
66 
67 	/*
68 	 * Tests using a writable file: grow and then shrink a file
69 	 * using ftruncate and various lengths.  Make sure that a negative
70 	 * file length is rejected.  Make sure that when we grow the file,
71 	 * bytes now in the range of the file size return 0.
72 	 *
73 	 * Save a read-only reference to the file to use later for read-only
74 	 * descriptor tests.
75 	 */
76 	fd = open(path, O_RDWR|O_CREAT, 0600);
77 	if (fd < 0)
78 		err(1, "open(%s, O_RDWR|O_CREAT, 0600)", path);
79 	read_only_fd = open(path, O_RDONLY);
80 	if (read_only_fd < 0) {
81 		error = errno;
82 		(void)unlink(path);
83 		errno = error;
84 		err(1, "open(%s, O_RDONLY)", path);
85 	}
86 	(void)unlink(path);
87 
88 	if (ftruncate(fd, -1) == 0)
89 		errx(1, "ftruncate(fd, -1) succeeded unexpectedly");
90 	if (errno != EINVAL)
91 		err(1, "ftruncate(fd, -1) returned wrong error");
92 
93 	for (i = 0; i < lengths_count; i++) {
94 		len = lengths[i];
95 		if (ftruncate(fd, len) < 0)
96 			err(1, "ftruncate(%jd) up", (intmax_t)len);
97 		if (fstat(fd, &sb) < 0)
98 			err(1, "stat");
99 		if (sb.st_size != len)
100 			errx(-1, "fstat with len=%jd returned len %jd up",
101 			    (intmax_t)len, (intmax_t)sb.st_size);
102 		if (len != 0) {
103 			size = pread(fd, &ch, sizeof(ch), len - 1);
104 			if (size < 0)
105 				err(1, "pread on len %jd up", (intmax_t)len);
106 			if (size != sizeof(ch))
107 				errx(-1, "pread len %jd size %jd up",
108 				    (intmax_t)len, (intmax_t)size);
109 			if (ch != 0)
110 				errx(-1,
111 				    "pread length %jd size %jd ch %d up",
112 				    (intmax_t)len, (intmax_t)size, ch);
113 		}
114 	}
115 
116 	for (i = lengths_count - 1; i >= 0; i--) {
117 		len = lengths[i];
118 		if (ftruncate(fd, len) < 0)
119 			err(1, "ftruncate(%jd) down", (intmax_t)len);
120 		if (fstat(fd, &sb) < 0)
121 			err(1, "stat");
122 		if (sb.st_size != len)
123 			errx(-1, "fstat(%jd) returned %jd down", (intmax_t)len,
124 			    sb.st_size);
125 	}
126 	close(fd);
127 
128 	/*
129 	 * Make sure that a read-only descriptor can't be truncated.
130 	 */
131 	if (ftruncate(read_only_fd, 0) == 0)
132 		errx(-1, "ftruncate(read_only_fd) succeeded");
133 	if (errno != EINVAL)
134 		err(1, "ftruncate(read_only_fd) returned wrong error");
135 	close(read_only_fd);
136 
137 	/*
138 	 * Make sure that ftruncate on sockets doesn't work.
139 	 */
140 	fd = socket(PF_UNIX, SOCK_STREAM, 0);
141 	if (fd < 0)
142 		err(1, "socket(PF_UNIX, SOCK_STREAM, 0)");
143 	if (ftruncate(fd, 0) == 0)
144 		errx(-1, "ftruncate(socket) succeeded");
145 	if (errno != EINVAL)
146 		err(1, "ftruncate(socket) returned wrong error");
147 	close(fd);
148 
149 	/*
150 	 * Make sure that ftruncate on pipes doesn't work.
151 	 */
152 	if (pipe(fds) < 0)
153 		err(1, "pipe");
154 	if (ftruncate(fds[0], 0) == 0)
155 		errx(-1, "ftruncate(pipe) succeeded");
156 	if (errno != EINVAL)
157 		err(1, "ftruncate(pipe) returned wrong error");
158 	close(fds[0]);
159 	close(fds[1]);
160 
161 	/*
162 	 * Make sure that ftruncate on kqueues doesn't work.
163 	 */
164 	fd = kqueue();
165 	if (fd < 0)
166 		err(1, "kqueue");
167 	if (ftruncate(fds[0], 0) == 0)
168 		errx(-1, "ftruncate(kqueue) succeeded");
169 	if (errno != EINVAL)
170 		err(1, "ftruncate(kqueue) returned wrong error");
171 	close(fd);
172 
173 	return (0);
174 }
175