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 <sys/event.h>
30 #include <assert.h>
31 #include <err.h>
32 #include <errno.h>
33 #include <inttypes.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <unistd.h>
37
38 /*
39 * $FreeBSD$
40 * The goal of this program is to see if fstat reports the correct
41 * data count for a pipe. Prior to revision 1.172 of sys_pipe.c,
42 * 0 would be returned once the pipe entered direct write mode.
43 *
44 * Linux (2.6) always returns zero, so it's not a valuable platform
45 * for comparison.
46 */
47
48 int
main(void)49 main(void)
50 {
51 char buffer[32768], buffer2[32768], go[] = "go", go2[] = "go2";
52 int desc[2], ipc_coord[2];
53 struct kevent event, ke;
54 ssize_t error;
55 int successes = 0;
56 struct stat status;
57 pid_t new_pid;
58 int kq;
59
60 error = pipe(desc);
61 if (error == -1)
62 err(1, "Couldn't allocate data pipe");
63
64 error = pipe(ipc_coord);
65 if (error == -1)
66 err(1, "Couldn't allocate IPC coordination pipe");
67
68 new_pid = fork();
69 assert(new_pid != -1);
70
71 close(new_pid == 0 ? desc[0] : desc[1]);
72
73 #define SYNC_R(i, _buf) do { \
74 int _error = errno; \
75 warnx("%d: waiting for synchronization", __LINE__); \
76 if (read(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
77 err(1, "failed to synchronize (%s)", (i == 0 ? "parent" : "child")); \
78 errno = _error; \
79 } while(0)
80
81 #define SYNC_W(i, _buf) do { \
82 int _error = errno; \
83 warnx("%d: sending synchronization", __LINE__); \
84 if (write(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
85 err(1, "failed to synchronize (%s)", (i == 0 ? "child" : "parent")); \
86 errno = _error; \
87 } while(0)
88
89 #define WRITE(s) do { \
90 ssize_t _size; \
91 if ((_size = write(desc[1], &buffer, s)) != s) \
92 warn("short write; wrote %zd, expected %d", _size, s); \
93 } while(0)
94
95 if (new_pid == 0) {
96
97 SYNC_R(0, go);
98 WRITE(145);
99 SYNC_W(0, go2);
100
101 SYNC_R(0, go);
102 WRITE(2048);
103 SYNC_W(0, go2);
104
105 SYNC_R(0, go);
106 WRITE(4096);
107 SYNC_W(0, go2);
108
109 SYNC_R(0, go);
110 WRITE(8191);
111 SYNC_W(0, go2);
112
113 SYNC_R(0, go);
114 SYNC_W(0, go2); /* XXX: why is this required? */
115 WRITE(8192);
116 SYNC_W(0, go2);
117
118 close(ipc_coord[0]);
119 close(ipc_coord[1]);
120
121 _exit(0);
122 }
123
124 kq = kqueue();
125 if (kq == -1)
126 _exit(1);
127
128 EV_SET(&ke, desc[0], EVFILT_READ, EV_ADD, 0, 0, NULL);
129
130 /* Attach event to the kqueue. */
131 if (kevent(kq, &ke, 1, NULL, 0, NULL) != 0)
132 _exit(2);
133
134 while (successes < 5) {
135 SYNC_W(1, go);
136 SYNC_R(1, go2);
137
138 /* Ensure data is available to read */
139 if (kevent(kq, NULL, 0, &event, 1, NULL) != 1)
140 _exit(3);
141
142 fstat(desc[0], &status);
143 error = read(desc[0], &buffer2, sizeof(buffer2));
144
145 if (status.st_size != error)
146 err(1, "FAILURE: stat size %jd read size %zd",
147 (intmax_t)status.st_size, error);
148 if (error > 0) {
149 printf("SUCCESS at stat size %jd read size %zd\n",
150 (intmax_t)status.st_size, error);
151 successes++;
152 }
153 }
154
155 exit(0);
156 }
157