sigaction01.c revision d6d11d08678aac1ed2c370ea8e42e5f45aea07be 
1/*
2 *
3 *   Copyright (c) International Business Machines  Corp., 2001
4 *
5 *   This program is free software;  you can redistribute it and/or modify
6 *   it under the terms of the GNU General Public License as published by
7 *   the Free Software Foundation; either version 2 of the License, or
8 *   (at your option) any later version.
9 *
10 *   This program is distributed in the hope that it will be useful,
11 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
13 *   the GNU General Public License for more details.
14 *
15 *   You should have received a copy of the GNU General Public License
16 *   along with this program;  if not, write to the Free Software
17 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20/*
21 * NAME
22 * 	sigaction01.c
23 *
24 * DESCRIPTION
25 * 	Test some features of sigaction (see below for more details)
26 *
27 * ALGORITHM
28 * 	Use sigaction(2) to set a signal handler for SIGUSR1 with a certain
29 * 	set of flags, set a global variable indicating the test case, and
30 * 	finally send the signal to ourselves, causing the signal handler to
31 * 	run. The signal handler then checks the signal handler to run. The
32 * 	signal handler then checks certain conditions based on the test case
33 * 	number.
34 * 	There are 4 test cases:
35 *
36 * 	1) Set SA_RESETHAND and SA_SIGINFO. When the handler runs,
37 * 	SA_SIGINFO should be set.
38 *
39 * 	2) Set SA_RESETHAND. When the handler runs, SIGUSR1 should be
40 * 	masked (SA_RESETHAND makes sigaction behave as if SA_NODEFER was
41 * 	not set).
42 *
43 * 	3) Same as case #2, but when the handler is established, sa_mask is
44 * 	set to include SIGUSR1. Ensure that SIGUSR1 is indeed masked even if
45 * 	SA_RESETHAND is set.
46 *
47 * 	4) A signal generated from an interface or condition that does not
48 * 	provide siginfo (such as pthread_kill(3)) should invoke the handler
49 * 	with a non-NULL siginfo pointer.
50 *
51 * USAGE:  <for command-line>
52 * sigaction01 [-c n] [-f] [-i n] [-I x] [-P x] [-t]
53 *     where,  -c n : Run n copies concurrently.
54 *             -f   : Turn off functionality Testing.
55 *             -i n : Execute test n times.
56 *             -I x : Execute test for x seconds.
57 *             -P x : Pause for x seconds between iterations.
58 *             -t   : Turn on syscall timing.
59 *
60 * HISTORY
61 *	07/2001 Ported by Wayne Boyer
62 *
63 * RESTRICTIONS
64 *	NONE
65 */
66#include <pthread.h>
67#include <signal.h>
68#include <errno.h>
69#include <stdlib.h>
70#include <unistd.h>
71#include "test.h"
72
73void setup();
74void cleanup();
75
76char *TCID = "sigaction01";
77int TST_TOTAL = 4;
78
79volatile sig_atomic_t testcase_no;
80volatile sig_atomic_t pass;
81
82/*
83 * handler()
84 *
85 * 	A signal handler that understands which test case is currently
86 * 	being executed and compares the current conditions to the ones it
87 * 	expects (based on the test case number).
88 */
89void handler(int sig, siginfo_t * sip, void *ucp)
90{
91	struct sigaction oact;
92	int err;
93	sigset_t nmask, omask;
94
95	/*
96	 * Get sigaction setting
97	 */
98	err = sigaction(SIGUSR1, NULL, &oact);
99
100	if (err == -1) {
101		perror("sigaction");
102		return;
103	}
104
105	/*
106	 * Get current signal mask
107	 */
108	sigemptyset(&nmask);
109	sigemptyset(&omask);
110	err = sigprocmask(SIG_BLOCK, &nmask, &omask);
111	if (err == -1) {
112		perror("sigprocmask");
113		tst_resm(TWARN, "sigprocmask() failed");
114		return;
115	}
116
117	switch (testcase_no) {
118	case 1:
119		/*
120		 * SA_RESETHAND and SA_SIGINFO were set. SA_SIGINFO should
121		 * be clear in Linux. In Linux kernel, SA_SIGINFO is not
122		 * cleared in psig().
123		 */
124		if (!(oact.sa_flags & SA_SIGINFO)) {
125			tst_resm(TFAIL, "SA_RESETHAND should not "
126				 "cause SA_SIGINFO to be cleared, but it was.");
127			return;
128		}
129		if (sip == NULL) {
130			tst_resm(TFAIL, "siginfo should not be NULL");
131			return;
132		}
133		tst_resm(TPASS, "SA_RESETHAND did not "
134			 "cause SA_SIGINFO to be cleared");
135		break;
136
137	case 2:
138		/*
139		 * In Linux, SA_RESETHAND doesn't imply SA_NODEFER; sig
140		 * should not be masked.  The testcase should pass if
141		 * SA_NODEFER is not masked, ie. if SA_NODEFER is a member
142		 * of the signal list
143		 */
144		if (sigismember(&omask, sig) == 0) {
145			tst_resm(TFAIL, "SA_RESETHAND should cause sig to"
146				 "be masked when the handler executes.");
147			return;
148		}
149		tst_resm(TPASS, "SA_RESETHAND was masked when handler "
150			 "executed");
151		break;
152
153	case 3:
154		/*
155		 * SA_RESETHAND implies SA_NODEFER unless sa_mask already
156		 * included sig.
157		 */
158		if (!sigismember(&omask, sig)) {
159			tst_resm(TFAIL, "sig should continue to be masked"
160				 "because sa_mask originally contained sig.");
161			return;
162		}
163		tst_resm(TPASS, "sig has been masked "
164			 "because sa_mask originally contained sig");
165		break;
166
167	case 4:
168		/*
169		 * A signal generated from a mechanism that does not provide
170		 * siginfo should invoke the handler with a non-NULL siginfo
171		 * pointer.
172		 */
173		if (sip == NULL) {
174			tst_resm(TFAIL, "siginfo pointer should not be NULL");
175			return;
176		}
177		tst_resm(TPASS, "siginfo pointer non NULL");
178		break;
179
180	default:
181		tst_resm(TFAIL, "invalid test case number: %d", testcase_no);
182		exit(1);
183	}
184}
185
186/*
187 * set_handler()
188 *
189 * 	Establish a signal handler for SIGUSR1 with the specified flags and
190 * 	signal to mask while the handler executes.
191 */
192int set_handler(int flags, int sig_to_mask)
193{
194	struct sigaction sa;
195
196	sa.sa_sigaction = handler;
197	sa.sa_flags = flags;
198	sigemptyset(&sa.sa_mask);
199	sigaddset(&sa.sa_mask, sig_to_mask);
200
201	TEST(sigaction(SIGUSR1, &sa, NULL));
202	if (TEST_RETURN != 0) {
203		perror("sigaction");
204		tst_resm(TFAIL, "call failed unexpectedly");
205		return 1;
206	}
207	return 0;
208}
209
210/*
211 * setup() - performs all ONE TIME setup for this test.
212 */
213void setup(void)
214{
215
216	TEST_PAUSE;
217}
218
219/*
220 * cleanup() - performs all ONE TIME cleanup for this test at
221 *	       completion or premature exit.
222 */
223void cleanup(void)
224{
225
226}
227
228int main(int ac, char **av)
229{
230	int lc;
231	int i;
232	int test_flags[] = { SA_RESETHAND | SA_SIGINFO, SA_RESETHAND,
233		SA_RESETHAND | SA_SIGINFO, SA_RESETHAND | SA_SIGINFO
234	};
235
236	tst_parse_opts(ac, av, NULL, NULL);
237
238	setup();
239
240	for (lc = 0; TEST_LOOPING(lc); lc++) {
241
242		/* reset tst_count in case we are looping */
243		tst_count = 0;
244
245		testcase_no = 0;
246
247		for (i = 0; i < TST_TOTAL; i++) {
248			if (set_handler(test_flags[i], 0) == 0) {
249				testcase_no++;
250				switch (i) {
251				case 0:
252				 /*FALLTHROUGH*/ case 1:
253					(void)kill(getpid(), SIGUSR1);
254					break;
255				case 2:
256				 /*FALLTHROUGH*/ case 3:
257					(void)
258					    pthread_kill(pthread_self(),
259							 SIGUSR1);
260					break;
261				default:
262					tst_brkm(TBROK, cleanup,
263						 "illegal case number");
264					break;
265				}
266			}
267		}
268	}
269
270	cleanup();
271	tst_exit();
272}
273