t_fifo.c revision 1.1 1 1.1 christos /* Test case written by Bharat Joshi */
2 1.1 christos #include <sys/cdefs.h>
3 1.1 christos __RCSID("$NetBSD: t_fifo.c,v 1.1 2011/12/21 00:17:07 christos Exp $");
4 1.1 christos
5 1.1 christos #include <sys/types.h>
6 1.1 christos #include <sys/wait.h>
7 1.1 christos
8 1.1 christos #include <stdio.h>
9 1.1 christos #include <stdlib.h>
10 1.1 christos #include <unistd.h>
11 1.1 christos #include <fcntl.h>
12 1.1 christos #include <errno.h>
13 1.1 christos #include <string.h>
14 1.1 christos #include <err.h>
15 1.1 christos #include <signal.h>
16 1.1 christos
17 1.1 christos #ifndef STANDALONE
18 1.1 christos #include <atf-c.h>
19 1.1 christos #endif
20 1.1 christos
21 1.1 christos #define FIFO_FILE_PATH "./fifo_file"
22 1.1 christos #define NUM_MESSAGES 20
23 1.1 christos #define MSG_SIZE 240
24 1.1 christos #define MESSAGE "I am fine"
25 1.1 christos
26 1.1 christos static int verbose = 0;
27 1.1 christos
28 1.1 christos /*
29 1.1 christos * child_writer
30 1.1 christos *
31 1.1 christos * Function that runs in child context and opens and write to the FIFO.
32 1.1 christos */
33 1.1 christos static void
34 1.1 christos child_writer(void)
35 1.1 christos {
36 1.1 christos ssize_t rv;
37 1.1 christos int fd;
38 1.1 christos size_t count;
39 1.1 christos char message[MSG_SIZE] = MESSAGE;
40 1.1 christos static const struct timespec ts = { 0, 10000 };
41 1.1 christos
42 1.1 christos /* Open the fifo in write-mode */
43 1.1 christos for (;;) {
44 1.1 christos fd = open(FIFO_FILE_PATH, O_WRONLY, 0);
45 1.1 christos if (fd == -1) {
46 1.1 christos if (errno == EINTR)
47 1.1 christos continue;
48 1.1 christos err(1, "Child: can't open fifo in write mode");
49 1.1 christos }
50 1.1 christos break;
51 1.1 christos }
52 1.1 christos
53 1.1 christos for (count = 0; count < NUM_MESSAGES; count++) {
54 1.1 christos rv = write(fd, message, MSG_SIZE);
55 1.1 christos if (rv == -1) {
56 1.1 christos warn("Child: Failed to write");
57 1.1 christos break;
58 1.1 christos }
59 1.1 christos if (rv != MSG_SIZE)
60 1.1 christos warnx("Child: wrote only %zd", rv);
61 1.1 christos nanosleep(&ts, NULL);
62 1.1 christos }
63 1.1 christos
64 1.1 christos close(fd);
65 1.1 christos if (verbose) {
66 1.1 christos printf("Child: Closed the fifo file\n");
67 1.1 christos fflush(stdout);
68 1.1 christos }
69 1.1 christos }
70 1.1 christos
71 1.1 christos /*
72 1.1 christos * _sigchild_handler
73 1.1 christos *
74 1.1 christos * Called when a sigchild is delivered
75 1.1 christos */
76 1.1 christos static void
77 1.1 christos sigchild_handler(int signo)
78 1.1 christos {
79 1.1 christos if (verbose) {
80 1.1 christos if (signo == SIGCHLD) {
81 1.1 christos printf("Got sigchild\n");
82 1.1 christos } else {
83 1.1 christos printf("Got %d signal\n", signo);
84 1.1 christos }
85 1.1 christos fflush(stdout);
86 1.1 christos }
87 1.1 christos
88 1.1 christos }
89 1.1 christos
90 1.1 christos static int
91 1.1 christos run(void)
92 1.1 christos {
93 1.1 christos pid_t pid;
94 1.1 christos ssize_t rv;
95 1.1 christos int fd, status;
96 1.1 christos size_t buf_size = MSG_SIZE;
97 1.1 christos char buf[MSG_SIZE];
98 1.1 christos struct sigaction action;
99 1.1 christos static const struct timespec ts = { 0, 500000000 };
100 1.1 christos
101 1.1 christos /* Catch sigchild Signal */
102 1.1 christos memset(&action, 0, sizeof(action));
103 1.1 christos action.sa_handler = sigchild_handler;
104 1.1 christos sigemptyset(&action.sa_mask);
105 1.1 christos
106 1.1 christos if (sigaction(SIGCHLD, &action, NULL) == -1)
107 1.1 christos err(1, "sigaction");
108 1.1 christos
109 1.1 christos (void)unlink(FIFO_FILE_PATH);
110 1.1 christos /* First create a fifo */
111 1.1 christos if (mkfifo(FIFO_FILE_PATH, S_IRUSR | S_IWUSR) == -1)
112 1.1 christos err(1, "mkfifo");
113 1.1 christos
114 1.1 christos switch ((pid = fork())) {
115 1.1 christos case -1:
116 1.1 christos err(1, "fork");
117 1.1 christos case 0:
118 1.1 christos /* Open the file in write mode so that subsequent read
119 1.1 christos * from parent side does not block the parent..
120 1.1 christos */
121 1.1 christos if ((fd = open(FIFO_FILE_PATH, O_WRONLY, 0)) == -1)
122 1.1 christos err(1, "failed to open fifo");
123 1.1 christos
124 1.1 christos /* In child */
125 1.1 christos child_writer();
126 1.1 christos return 0;
127 1.1 christos
128 1.1 christos default:
129 1.1 christos break;
130 1.1 christos }
131 1.1 christos
132 1.1 christos if (verbose) {
133 1.1 christos printf("Child pid is %d\n", pid );
134 1.1 christos fflush(stdout);
135 1.1 christos }
136 1.1 christos
137 1.1 christos /* In parent */
138 1.1 christos for (;;) {
139 1.1 christos if ((fd = open(FIFO_FILE_PATH, O_RDONLY, 0)) == -1) {
140 1.1 christos if (errno == EINTR)
141 1.1 christos continue;
142 1.1 christos else
143 1.1 christos err(1, "Failed to open the fifo in read mode");
144 1.1 christos }
145 1.1 christos /* Read mode is opened */
146 1.1 christos break;
147 1.1 christos
148 1.1 christos }
149 1.1 christos
150 1.1 christos nanosleep(&ts, NULL);
151 1.1 christos if (verbose) {
152 1.1 christos printf("Was sleeping...\n");
153 1.1 christos fflush(stdout);
154 1.1 christos }
155 1.1 christos
156 1.1 christos for (;;) {
157 1.1 christos rv = read(fd, buf, buf_size);
158 1.1 christos
159 1.1 christos if (rv == -1) {
160 1.1 christos warn("Failed to read");
161 1.1 christos if (errno == EINTR) {
162 1.1 christos if (verbose) {
163 1.1 christos printf("Parent interrupted, "
164 1.1 christos "continuing...\n");
165 1.1 christos fflush(stdout);
166 1.1 christos }
167 1.1 christos continue;
168 1.1 christos }
169 1.1 christos
170 1.1 christos break;
171 1.1 christos }
172 1.1 christos
173 1.1 christos if (rv == 0) {
174 1.1 christos if (verbose) {
175 1.1 christos printf("Writers have closed, looks like we "
176 1.1 christos "are done\n");
177 1.1 christos fflush(stdout);
178 1.1 christos }
179 1.1 christos break;
180 1.1 christos }
181 1.1 christos
182 1.1 christos if (verbose) {
183 1.1 christos printf("Received %zd bytes message '%s'\n", rv, buf);
184 1.1 christos fflush(stdout);
185 1.1 christos }
186 1.1 christos }
187 1.1 christos
188 1.1 christos close(fd);
189 1.1 christos
190 1.1 christos if (verbose) {
191 1.1 christos printf("We are done.. now reap the child");
192 1.1 christos fflush(stdout);
193 1.1 christos }
194 1.1 christos
195 1.1 christos // Read the child...
196 1.1 christos while (waitpid(pid, &status, 0) == -1)
197 1.1 christos if (errno != EINTR) {
198 1.1 christos warn("Failed to reap the child");
199 1.1 christos return 1;
200 1.1 christos }
201 1.1 christos
202 1.1 christos if (verbose) {
203 1.1 christos printf("We are done completely\n");
204 1.1 christos fflush(stdout);
205 1.1 christos }
206 1.1 christos return 0;
207 1.1 christos }
208 1.1 christos
209 1.1 christos #ifndef STANDALONE
210 1.1 christos ATF_TC(parent_child);
211 1.1 christos
212 1.1 christos ATF_TC_HEAD(parent_child, tc)
213 1.1 christos {
214 1.1 christos atf_tc_set_md_var(tc, "descr", "Checks that when a fifo is shared "
215 1.1 christos "between a reader parent and a writer child, that read will "
216 1.1 christos "return EOF, and not get stuck after the child exits");
217 1.1 christos }
218 1.1 christos
219 1.1 christos ATF_TC_BODY(parent_child, tc)
220 1.1 christos {
221 1.1 christos ATF_REQUIRE(run() == 0);
222 1.1 christos }
223 1.1 christos
224 1.1 christos ATF_TP_ADD_TCS(tp)
225 1.1 christos {
226 1.1 christos ATF_TP_ADD_TC(tp, parent_child);
227 1.1 christos
228 1.1 christos return atf_no_error();
229 1.1 christos }
230 1.1 christos #else
231 1.1 christos int
232 1.1 christos main(void)
233 1.1 christos {
234 1.1 christos verbose = 1;
235 1.1 christos return run();
236 1.1 christos }
237 1.1 christos #endif
238