xref: /openbsd/regress/lib/libc/sys/t_pipe.c (revision 49a6e16f)
1 /*	$OpenBSD: t_pipe.c,v 1.3 2021/12/13 16:56:48 deraadt Exp $	*/
2 /* $NetBSD: t_pipe.c,v 1.7 2020/06/26 07:50:11 jruoho Exp $ */
3 
4 /*-
5  * Copyright (c) 2001, 2008 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include "macros.h"
31 
32 #include <sys/types.h>
33 #include <sys/wait.h>
34 
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <poll.h>
38 #include <sched.h>
39 #include <signal.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <unistd.h>
43 
44 #include "atf-c.h"
45 
46 #include "h_macros.h"
47 
48 static pid_t pid;
49 static int nsiginfo = 0;
50 
51 /*
52  * This is used for both parent and child. Handle parent's SIGALRM,
53  * the childs SIGINFO doesn't need anything.
54  */
55 static void
sighand(int sig)56 sighand(int sig)
57 {
58 	if (sig == SIGALRM) {
59 		kill(pid, SIGINFO);
60 	}
61 	if (sig == SIGINFO) {
62 		nsiginfo++;
63 	}
64 }
65 
66 ATF_TC(pipe_restart);
ATF_TC_HEAD(pipe_restart,tc)67 ATF_TC_HEAD(pipe_restart, tc)
68 {
69 	atf_tc_set_md_var(tc, "descr", "Checks that writing to pipe "
70 	    "works correctly after being interrupted and restarted "
71 	    "(PR kern/14087)");
72 }
73 
ATF_TC_BODY(pipe_restart,tc)74 ATF_TC_BODY(pipe_restart, tc)
75 {
76 	int pp[2], st;
77 	ssize_t sz, todo, done;
78 	char *f;
79 	sigset_t asigset, osigset, emptysigset;
80 
81 	/* Initialise signal masks */
82 	RL(sigemptyset(&emptysigset));
83 	RL(sigemptyset(&asigset));
84 	RL(sigaddset(&asigset, SIGINFO));
85 
86 	/* Register signal handlers for both read and writer */
87 	REQUIRE_LIBC(signal(SIGINFO, sighand), SIG_ERR);
88 	REQUIRE_LIBC(signal(SIGALRM, sighand), SIG_ERR);
89 
90 	todo = 2 * 1024 * 1024;
91 	REQUIRE_LIBC(f = malloc(todo), NULL);
92 
93 	RL(pipe(pp));
94 
95 	RL(pid = fork());
96 	if (pid == 0) {
97 		/* child */
98 		RL(close(pp[1]));
99 
100 		/* Do initial write. This should succeed, make
101 		 * the other side do partial write and wait for us to pick
102 		 * rest up.
103 		 */
104 		RL(done = read(pp[0], f, 128 * 1024));
105 
106 		/* Wait until parent is alarmed and awakens us */
107 		RL(sigprocmask(SIG_BLOCK, &asigset, &osigset));
108 		while (nsiginfo == 0) {
109 			if (sigsuspend(&emptysigset) != -1 || errno != EINTR)
110 				atf_tc_fail("sigsuspend(&emptysigset): %s",
111 				    strerror(errno));
112 		}
113 		RL(sigprocmask(SIG_SETMASK, &osigset, NULL));
114 
115 		/* Read all what parent wants to give us */
116 		while((sz = read(pp[0], f, 1024 * 1024)) > 0)
117 			done += sz;
118 
119 		/*
120 		 * Exit with 1 if number of bytes read doesn't match
121 		 * number of expected bytes
122 		 */
123 		printf("Read:     %#zx\n", (size_t)done);
124 		printf("Expected: %#zx\n", (size_t)todo);
125 
126 		exit(done != todo);
127 
128 		/* NOTREACHED */
129 	} else {
130 		RL(close(pp[0]));
131 
132 		/*
133 		 * Arrange for alarm after two seconds. Since we have
134 		 * handler setup for SIGARLM, the write(2) call should
135 		 * be restarted internally by kernel.
136 		 */
137 		(void)alarm(2);
138 
139 		/* We write exactly 'todo' bytes. The very first write(2)
140 		 * should partially succeed, block and eventually
141 		 * be restarted by kernel
142 		 */
143 		while(todo > 0 && ((sz = write(pp[1], f, todo)) > 0))
144 			todo -= sz;
145 
146 		/* Close the pipe, so that child would stop reading */
147 		RL(close(pp[1]));
148 
149 		/* And pickup child's exit status */
150 		RL(waitpid(pid, &st, 0));
151 
152 		ATF_REQUIRE_EQ(WEXITSTATUS(st), 0);
153 	}
154 	free(f);
155 }
156 
ATF_TP_ADD_TCS(tp)157 ATF_TP_ADD_TCS(tp)
158 {
159 	ATF_TP_ADD_TC(tp, pipe_restart);
160 
161 	return atf_no_error();
162 }
163