1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) International Business Machines Corp., 2001
4 * 07/2001 Ported by Wayne Boyer
5 * Copyright (C) Cyril Hrubis <chrubis@suse.cz>
6 */
7
8 /*
9 * Test Description:
10 * Verify that nanosleep() will be successful to suspend the execution
11 * of a process, returns after the receipt of a signal and writes the
12 * remaining sleep time into the structure.
13 *
14 * This test also verifies that if the call is interrupted by a signal
15 * handler, nanosleep() returns -1, sets errno to EINTR.
16 */
17
18 #include <errno.h>
19
20 #include "tst_test.h"
21 #include "tst_timer.h"
22 #include "tst_safe_macros.h"
23
24 /*
25 * Define here the "rem" precision in microseconds,
26 * Various implementations will provide different
27 * precisions. The -aa tree provides up to usec precision.
28 * NOTE: all the trees that don't provide a precision of
29 * the order of the microseconds are subject to an userspace
30 * live lock condition with glibc under a flood of signals,
31 * the "rem" field would never change without the increased
32 * usec precision in the -aa tree.
33 */
34 #define USEC_PRECISION 250000 /* Error margin allowed in usec */
35
do_child(void)36 static void do_child(void)
37 {
38 struct timespec timereq = {.tv_sec = 5, .tv_nsec = 9999};
39 struct timespec timerem, exp_rem;
40
41 tst_timer_start(CLOCK_MONOTONIC);
42 TEST(nanosleep(&timereq, &timerem));
43 tst_timer_stop();
44
45 if (TST_RET != -1) {
46 tst_res(TFAIL,
47 "nanosleep was not interrupted, returned %ld, expected -1",
48 TST_RET);
49 return;
50 }
51 if (TST_ERR != EINTR) {
52 tst_res(TFAIL | TTERRNO,
53 "nanosleep() failed, expected EINTR, got");
54 return;
55 }
56
57 tst_res(TPASS, "nanosleep() returned -1, set errno to EINTR");
58
59 if (tst_timespec_lt(timereq, tst_timer_elapsed()))
60 tst_brk(TFAIL, "nanosleep() slept more than timereq");
61
62 exp_rem = tst_timespec_diff(timereq, tst_timer_elapsed());
63
64 if (tst_timespec_abs_diff_us(timerem, exp_rem) > USEC_PRECISION) {
65 tst_res(TFAIL,
66 "nanosleep() remaining time %llius, expected %llius, diff %llius",
67 tst_timespec_to_us(timerem), tst_timespec_to_us(exp_rem),
68 tst_timespec_abs_diff_us(timerem, exp_rem));
69 } else {
70 tst_res(TPASS,
71 "nanosleep() slept for %llius, remaining time difference %llius",
72 tst_timer_elapsed_us(),
73 tst_timespec_abs_diff_us(timerem, exp_rem));
74 }
75 }
76
run(void)77 void run(void)
78 {
79 pid_t cpid;
80
81 cpid = SAFE_FORK();
82 if (cpid == 0) {
83 do_child();
84 } else {
85 sleep(1);
86
87 SAFE_KILL(cpid, SIGINT);
88
89 tst_reap_children();
90 }
91 }
92
sig_handler(int si LTP_ATTRIBUTE_UNUSED)93 static void sig_handler(int si LTP_ATTRIBUTE_UNUSED)
94 {
95 }
96
setup(void)97 static void setup(void)
98 {
99 tst_timer_check(CLOCK_MONOTONIC);
100 SAFE_SIGNAL(SIGINT, sig_handler);
101 }
102
103 static struct tst_test test = {
104 .forks_child = 1,
105 .setup = setup,
106 .test_all = run,
107 };
108