xref: /freebsd/contrib/netbsd-tests/lib/libc/sys/t_pipe.c (revision 580744621f33383027108364dcadad718df46ffe)
1 /* $NetBSD: t_pipe.c,v 1.5 2017/01/13 21:30:41 christos Exp $ */
2 
3 /*-
4  * Copyright (c) 2001, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __COPYRIGHT("@(#) Copyright (c) 2008\
31  The NetBSD Foundation, inc. All rights reserved.");
32 __RCSID("$NetBSD: t_pipe.c,v 1.5 2017/01/13 21:30:41 christos Exp $");
33 
34 #include <sys/types.h>
35 #include <sys/wait.h>
36 
37 #include <errno.h>
38 #include <fcntl.h>
39 #include <poll.h>
40 #include <sched.h>
41 #include <signal.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <unistd.h>
45 
46 #include <atf-c.h>
47 
48 #include "h_macros.h"
49 
50 static pid_t pid;
51 static int nsiginfo = 0;
52 
53 /*
54  * This is used for both parent and child. Handle parent's SIGALRM,
55  * the childs SIGINFO doesn't need anything.
56  */
57 static void
58 sighand(int sig)
59 {
60 	if (sig == SIGALRM) {
61 		kill(pid, SIGINFO);
62 	}
63 	if (sig == SIGINFO) {
64 		nsiginfo++;
65 	}
66 }
67 
68 ATF_TC(pipe_restart);
69 ATF_TC_HEAD(pipe_restart, tc)
70 {
71 	atf_tc_set_md_var(tc, "descr", "Checks that writing to pipe "
72 	    "works correctly after being interrupted and restarted "
73 	    "(kern/14087)");
74 }
75 
76 ATF_TC_BODY(pipe_restart, tc)
77 {
78 	int pp[2], st;
79 	ssize_t sz, todo, done;
80 	char *f;
81 	sigset_t asigset, osigset, emptysigset;
82 
83 	/* Initialise signal masks */
84 	RL(sigemptyset(&emptysigset));
85 	RL(sigemptyset(&asigset));
86 	RL(sigaddset(&asigset, SIGINFO));
87 
88 	/* Register signal handlers for both read and writer */
89 	REQUIRE_LIBC(signal(SIGINFO, sighand), SIG_ERR);
90 	REQUIRE_LIBC(signal(SIGALRM, sighand), SIG_ERR);
91 
92 	todo = 2 * 1024 * 1024;
93 	REQUIRE_LIBC(f = malloc(todo), NULL);
94 
95 	RL(pipe(pp));
96 
97 	RL(pid = fork());
98 	if (pid == 0) {
99 		/* child */
100 		RL(close(pp[1]));
101 
102 		/* Do inital write. This should succeed, make
103 		 * the other side do partial write and wait for us to pick
104 		 * rest up.
105 		 */
106 		RL(done = read(pp[0], f, 128 * 1024));
107 
108 		/* Wait until parent is alarmed and awakens us */
109 		RL(sigprocmask(SIG_BLOCK, &asigset, &osigset));
110 		while (nsiginfo == 0) {
111 			if (sigsuspend(&emptysigset) != -1 || errno != EINTR)
112 				atf_tc_fail("sigsuspend(&emptysigset): %s",
113 				    strerror(errno));
114 		}
115 		RL(sigprocmask(SIG_SETMASK, &osigset, NULL));
116 
117 		/* Read all what parent wants to give us */
118 		while((sz = read(pp[0], f, 1024 * 1024)) > 0)
119 			done += sz;
120 
121 		/*
122 		 * Exit with 1 if number of bytes read doesn't match
123 		 * number of expected bytes
124 		 */
125 		printf("Read:     %#zx\n", (size_t)done);
126 		printf("Expected: %#zx\n", (size_t)todo);
127 
128 		exit(done != todo);
129 
130 		/* NOTREACHED */
131 	} else {
132 		RL(close(pp[0]));
133 
134 		/*
135 		 * Arrange for alarm after two seconds. Since we have
136 		 * handler setup for SIGARLM, the write(2) call should
137 		 * be restarted internally by kernel.
138 		 */
139 		(void)alarm(2);
140 
141 		/* We write exactly 'todo' bytes. The very first write(2)
142 		 * should partially succeed, block and eventually
143 		 * be restarted by kernel
144 		 */
145 		while(todo > 0 && ((sz = write(pp[1], f, todo)) > 0))
146 			todo -= sz;
147 
148 		/* Close the pipe, so that child would stop reading */
149 		RL(close(pp[1]));
150 
151 		/* And pickup child's exit status */
152 		RL(waitpid(pid, &st, 0));
153 
154 		ATF_REQUIRE_EQ(WEXITSTATUS(st), 0);
155 	}
156 	free(f);
157 }
158 
159 ATF_TP_ADD_TCS(tp)
160 {
161 	ATF_TP_ADD_TC(tp, pipe_restart);
162 
163 	return atf_no_error();
164 }
165