xref: /freebsd/tests/sys/kern/pipe/pipe_wraparound_test.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
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  * This program tests to make sure that wraparound writes and reads
39  * are working, assuming that 16K socket buffers are used.  In order
40  * to really stress the pipe code with this test, kernel modifications
41  * nay be necessary.
42  */
43 
44 int main (void)
45 {
46 	char buffer[32768], buffer2[32768], go[] = "go", go2[] = "go2";
47 	int desc[2], ipc_coord[2];
48 	ssize_t error, total;
49 	int buggy, i;
50 	pid_t new_pid;
51 
52 	buggy = 0;
53 	total = 0;
54 
55 	error = pipe(desc);
56 	if (error == -1)
57 		err(1, "Couldn't allocate data pipe");
58 
59 	error = pipe(ipc_coord);
60 	if (error == -1)
61 		err(1, "Couldn't allocate IPC coordination pipe");
62 
63 	buffer[0] = 'A';
64 
65 	for (i = 1; i < (int)sizeof(buffer); i++) {
66 		buffer[i] = buffer[i - 1] + 1;
67 		if (buffer[i] > 'Z')
68 			buffer[i] = 'A';
69 	}
70 
71 	new_pid = fork();
72 	assert(new_pid != -1);
73 
74 #define	SYNC_R(i, _buf) do {	\
75 	int _error = errno; \
76 	warnx("%d: waiting for synchronization", __LINE__); \
77 	if (read(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
78 		err(1, "failed to synchronize (%s)", (i == 0 ? "parent" : "child")); \
79 	errno = _error; \
80 	} while(0)
81 
82 #define	SYNC_W(i, _buf) do {	\
83 	int _error = errno; \
84 	warnx("%d: sending synchronization", __LINE__); \
85 	if (write(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \
86 		err(1, "failed to synchronize (%s)", (i == 0 ? "child" : "parent")); \
87 	errno = _error; \
88 	} while(0)
89 
90 #define	WRITE(s) do { 							\
91 	ssize_t _size; 							\
92 	if ((_size = write(desc[1], &buffer[total], s)) != s)		\
93 		warn("short write; wrote %zd, expected %d", _size, s);	\
94 	total += _size;							\
95 	} while(0)
96 
97 	if (new_pid == 0) {
98 		WRITE(4096);
99 		WRITE(4096);
100 		WRITE(4000);
101 		SYNC_W(0, go2);
102 
103 		SYNC_R(0, go);
104 		WRITE(3000);
105 		WRITE(3000);
106 		SYNC_W(0, go2);
107 
108 		_exit(0);
109 	}
110 
111 	SYNC_R(1, go2);
112 	error = read(desc[0], &buffer2, 8192);
113 	total += error;
114 	printf("Read %zd bytes\n", error);
115 	SYNC_W(1, go);
116 	SYNC_R(1, go2);
117 	error = read(desc[0], &buffer2[total], 16384);
118 	total += error;
119 	printf("Read %zd bytes, done\n", error);
120 
121 	if (memcmp(buffer, buffer2, total) != 0) {
122 		for (i = 0; i < total; i++) {
123 			if (buffer[i] != buffer2[i]) {
124 				buggy = 1;
125 				printf("Location %d input: %hhx output: %hhx\n",
126 				    i, buffer[i], buffer2[i]);
127 			}
128 		}
129 	}
130 
131 	waitpid(new_pid, NULL, 0);
132 
133 	if (buggy)
134 		errx(1, "FAILURE");
135 
136 	printf("SUCCESS\n");
137 
138 	exit(0);
139 }
140