xref: /freebsd/tests/sys/kern/pipe/pipe_fstat_bug_test.c (revision 86c9d9918f1db7cdd968b60f8902466887bcd9e9)
1 /*
2 Copyright (C) 2004 Michael J. Silbersack. All rights reserved.
3 
4 Redistribution and use in source and binary forms, with or without
5 modification, are permitted provided that the following conditions
6 are met:
7 1. Redistributions of source code must retain the above copyright
8    notice, this list of conditions and the following disclaimer.
9 2. Redistributions in binary form must reproduce the above copyright
10    notice, this list of conditions and the following disclaimer in the
11    documentation and/or other materials provided with the distribution.
12 
13 THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
17 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 SUCH DAMAGE.
24 */
25 
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <sys/wait.h>
29 #include <assert.h>
30 #include <err.h>
31 #include <errno.h>
32 #include <inttypes.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <unistd.h>
36 
37 /*
38  * $FreeBSD$
39  * The goal of this program is to see if fstat reports the correct
40  * data count for a pipe.  Prior to revision 1.172 of sys_pipe.c,
41  * 0 would be returned once the pipe entered direct write mode.
42  *
43  * Linux (2.6) always returns zero, so it's not a valuable platform
44  * for comparison.
45  */
46 
47 int
48 main(void)
49 {
50 	char buffer[32768], buffer2[32768], go[] = "go", go2[] = "go2";
51 	int desc[2], ipc_coord[2];
52 	ssize_t error;
53 	int successes = 0;
54 	struct stat status;
55 	pid_t new_pid;
56 
57 	error = pipe(desc);
58 	if (error == -1)
59 		err(1, "Couldn't allocate data pipe");
60 
61 	error = pipe(ipc_coord);
62 	if (error == -1)
63 		err(1, "Couldn't allocate IPC coordination pipe");
64 
65 	new_pid = fork();
66 	assert(new_pid != -1);
67 
68 	close(new_pid == 0 ? desc[0] : desc[1]);
69 
70 #define	SYNC_R(i, _buf) do {	\
71 	int _error = errno; \
72 	warnx("%d: waiting for synchronization", __LINE__); \
73 	if (read(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
74 		err(1, "failed to synchronize (%s)", (i == 0 ? "parent" : "child")); \
75 	errno = _error; \
76 	} while(0)
77 
78 #define	SYNC_W(i, _buf) do {	\
79 	int _error = errno; \
80 	warnx("%d: sending synchronization", __LINE__); \
81 	if (write(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
82 		err(1, "failed to synchronize (%s)", (i == 0 ? "child" : "parent")); \
83 	errno = _error; \
84 	} while(0)
85 
86 #define	WRITE(s) do { 							\
87 	ssize_t _size; 							\
88 	if ((_size = write(desc[1], &buffer, s)) != s)			\
89 		warn("short write; wrote %zd, expected %d", _size, s);	\
90 	} while(0)
91 
92 	if (new_pid == 0) {
93 
94 		SYNC_R(0, go);
95 		WRITE(145);
96 		SYNC_W(0, go2);
97 
98 		SYNC_R(0, go);
99 		WRITE(2048);
100 		SYNC_W(0, go2);
101 
102 		SYNC_R(0, go);
103 		WRITE(4096);
104 		SYNC_W(0, go2);
105 
106 		SYNC_R(0, go);
107 		WRITE(8191);
108 		SYNC_W(0, go2);
109 
110 		SYNC_R(0, go);
111 		SYNC_W(0, go2); /* XXX: why is this required? */
112 		WRITE(8192);
113 		SYNC_W(0, go2);
114 
115 		close(ipc_coord[0]);
116 		close(ipc_coord[1]);
117 
118 		_exit(0);
119 	}
120 
121 	while (successes < 5) {
122 		SYNC_W(1, go);
123 		SYNC_R(1, go2);
124 		fstat(desc[0], &status);
125 		error = read(desc[0], &buffer2, sizeof(buffer2));
126 
127 		if (status.st_size != error)
128 			err(1, "FAILURE: stat size %jd read size %zd",
129 			    (intmax_t)status.st_size, error);
130 		if (error > 0) {
131 			printf("SUCCESS at stat size %jd read size %zd\n",
132 			    (intmax_t)status.st_size, error);
133 			successes++;
134 		}
135 	}
136 
137 	exit(0);
138 }
139