1/*-
2 * Copyright (c) 2005 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 * $FreeBSD$
27 */
28
29#include <err.h>
30#include <errno.h>
31#include <fcntl.h>
32#include <limits.h>
33#include <stdio.h>
34#include <stdlib.h>
35#include <string.h>
36#include <unistd.h>
37
38/*
39 * This regression test attempts to exercise two instances of uprintf(9) in
40 * UFS: (1) when blocks are exhausted, and (2) when inodes are exhausted, in
41 * order to attempt to trigger races in the uprintf(9) code.  The test
42 * accepts a pointer to a path -- ideally, a very small UFS partition -- and
43 * then proceeds to fill it in various ways.
44 *
45 * This tool assumes that it is alright to create, and delete, entries in the
46 * directory with names of integer values.  Don't run this tool against a
47 * directory that has files with names along those lines if you want to keep
48 * the files.
49 *
50 * Suggested usage is:
51 *
52 * mdconfig -a -t malloc -s 512
53 * newfs /dev/mdX
54 * mount /dev/mdX /mnt
55 * ufs_uprintf /mnt
56 * umount /mnt
57 * mdconfig -d -u X
58 */
59
60#define	NUMTRIES	200
61
62/*
63 * Fill up the disk, then generate NUMTRIES additional ENOSPC errors.
64 */
65#define	BLOCKSIZE	1024
66#define	BLOCKS_FILENAME	"0"
67static void
68fill_blocks(void)
69{
70	char block[BLOCKSIZE];
71	ssize_t len;
72	int fd, i;
73
74	fd = open(BLOCKS_FILENAME, O_CREAT | O_TRUNC | O_RDWR, 0600);
75	if (fd < 0)
76		err(-1, "fill_blocks: open(%s)", BLOCKS_FILENAME);
77
78	/*
79	 * First step: fill the disk device.  Keep extending the file until
80	 * we hit our first error, and hope it is ENOSPC.
81	 */
82	bzero(block, BLOCKSIZE);
83	errno = 0;
84	while (1) {
85		len = write(fd, block, BLOCKSIZE);
86		if (len < 0)
87			break;
88		if (len != BLOCKSIZE) {
89			warnx("fill_blocks: write(%d) returned %zd",
90			    BLOCKSIZE, len);
91			close(fd);
92			(void)unlink(BLOCKS_FILENAME);
93			exit(-1);
94		}
95
96	}
97	if (errno != ENOSPC) {
98		warn("fill_blocks: write");
99		close(fd);
100		(void)unlink(BLOCKS_FILENAME);
101		exit(-1);
102	}
103
104	/*
105	 * Second step: generate NUMTRIES instances of the error by retrying
106	 * the write.
107	 */
108	for (i = 0; i < NUMTRIES; i++) {
109		len = write(fd, block, BLOCKSIZE);
110		if (len < 0 && errno != ENOSPC) {
111			warn("fill_blocks: write after ENOSPC");
112			close(fd);
113			(void)unlink(BLOCKS_FILENAME);
114			exit(-1);
115		}
116	}
117
118	close(fd);
119	(void)unlink(BLOCKS_FILENAME);
120}
121
122/*
123 * Create as many entries in the directory as we can, then once we start
124 * hitting ENOSPC, try NUMTRIES additional times.  Note that we don't be able
125 * to tell the difference between running out of inodes and running out of
126 * room to extend the directory, so this is just a best effort.
127 */
128static void
129fill_inodes(void)
130{
131	char path[PATH_MAX];
132	int fd, i, max;
133
134	/*
135	 * First step, fill the directory.
136	 */
137	i = 0;
138	while (1) {
139		snprintf(path, PATH_MAX, "%d", i);
140		fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
141		if (fd < 0)
142			break;
143		close(fd);
144		i++;
145	}
146	max = i;
147	if (errno != ENOSPC) {
148		warn("fill_inodes: open(%s)", path);
149		goto teardown;
150	}
151
152	for (i = 0; i < NUMTRIES; i++) {
153		fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
154		if (fd < 0 && errno != ENOSPC) {
155			warn("fill_inodes: open(%s) after ENOSPC", path);
156			goto teardown;
157		}
158		if (fd >= 0) {
159			warnx("fill_inodes: open(%s) after ENOSPC returned "
160			    " %d", path, fd);
161			close(fd);
162			goto teardown;
163		}
164	}
165
166teardown:
167	for (i = 0; i < max; i++) {
168		snprintf(path, PATH_MAX, "%d", i);
169		(void)unlink(path);
170	}
171}
172
173int
174main(int argc, char *argv[])
175{
176
177	if (argc != 2)
178		err(-1, "usage: ufs_uprintf /non_optional_path");
179
180	if (chdir(argv[1]) < 0)
181		err(-1, "chdir(%s)", argv[1]);
182
183	fill_blocks();
184
185	fill_inodes();
186
187	return (0);
188}
189