xref: /freebsd/tests/sys/kern/pipe/pipe_wraparound_test.c (revision d4eeb02986980bf33dd56c41ceb9fc5f180c0d47)
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 <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <unistd.h>
36 
37 /*
38  * $FreeBSD$
39  * This program tests to make sure that wraparound writes and reads
40  * are working, assuming that 16K socket buffers are used.  In order
41  * to really stress the pipe code with this test, kernel modifications
42  * nay be necessary.
43  */
44 
45 int main (void)
46 {
47 	char buffer[32768], buffer2[32768], go[] = "go", go2[] = "go2";
48 	int desc[2], ipc_coord[2];
49 	ssize_t error, total;
50 	int buggy, i;
51 	pid_t new_pid;
52 
53 	buggy = 0;
54 	total = 0;
55 
56 	error = pipe(desc);
57 	if (error == -1)
58 		err(1, "Couldn't allocate data pipe");
59 
60 	error = pipe(ipc_coord);
61 	if (error == -1)
62 		err(1, "Couldn't allocate IPC coordination pipe");
63 
64 	buffer[0] = 'A';
65 
66 	for (i = 1; i < (int)sizeof(buffer); i++) {
67 		buffer[i] = buffer[i - 1] + 1;
68 		if (buffer[i] > 'Z')
69 			buffer[i] = 'A';
70 	}
71 
72 	new_pid = fork();
73 	assert(new_pid != -1);
74 
75 #define	SYNC_R(i, _buf) do {	\
76 	int _error = errno; \
77 	warnx("%d: waiting for synchronization", __LINE__); \
78 	if (read(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
79 		err(1, "failed to synchronize (%s)", (i == 0 ? "parent" : "child")); \
80 	errno = _error; \
81 	} while(0)
82 
83 #define	SYNC_W(i, _buf) do {	\
84 	int _error = errno; \
85 	warnx("%d: sending synchronization", __LINE__); \
86 	if (write(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
87 		err(1, "failed to synchronize (%s)", (i == 0 ? "child" : "parent")); \
88 	errno = _error; \
89 	} while(0)
90 
91 #define	WRITE(s) do { 							\
92 	ssize_t _size; 							\
93 	if ((_size = write(desc[1], &buffer[total], s)) != s)		\
94 		warn("short write; wrote %zd, expected %d", _size, s);	\
95 	total += _size;							\
96 	} while(0)
97 
98 	if (new_pid == 0) {
99 		WRITE(4096);
100 		WRITE(4096);
101 		WRITE(4000);
102 		SYNC_W(0, go2);
103 
104 		SYNC_R(0, go);
105 		WRITE(3000);
106 		WRITE(3000);
107 		SYNC_W(0, go2);
108 
109 		_exit(0);
110 	}
111 
112 	SYNC_R(1, go2);
113 	error = read(desc[0], &buffer2, 8192);
114 	total += error;
115 	printf("Read %zd bytes\n", error);
116 	SYNC_W(1, go);
117 	SYNC_R(1, go2);
118 	error = read(desc[0], &buffer2[total], 16384);
119 	total += error;
120 	printf("Read %zd bytes, done\n", error);
121 
122 	if (memcmp(buffer, buffer2, total) != 0) {
123 		for (i = 0; i < total; i++) {
124 			if (buffer[i] != buffer2[i]) {
125 				buggy = 1;
126 				printf("Location %d input: %hhx output: %hhx\n",
127 				    i, buffer[i], buffer2[i]);
128 			}
129 		}
130 	}
131 
132 	waitpid(new_pid, NULL, 0);
133 
134 	if (buggy)
135 		errx(1, "FAILURE");
136 
137 	printf("SUCCESS\n");
138 
139 	exit(0);
140 }
141