1 /* Basic tests for getitimer and setitimer.
2    Copyright (C) 2021-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library 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 the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <array_length.h>
20 #include <errno.h>
21 #include <stdlib.h>
22 #include <sys/time.h>
23 #include <support/check.h>
24 #include <support/support.h>
25 #include <support/xsignal.h>
26 #include <unistd.h>
27 #include <time.h>
28 
29 static sig_atomic_t cnt;
30 
31 static void
alrm_handler(int sig)32 alrm_handler (int sig)
33 {
34   if (++cnt > 3)
35     cnt = 3;
36 }
37 
38 static void
intr_sleep(int sec)39 intr_sleep (int sec)
40 {
41   struct timespec ts = { .tv_sec = sec, .tv_nsec = 0 };
42   while (nanosleep (&ts, &ts) == -1 && errno == EINTR)
43     ;
44 }
45 
46 static int
do_test(void)47 do_test (void)
48 {
49   struct itimerval it, it_old;
50   const int timers[] = { ITIMER_REAL, ITIMER_VIRTUAL, ITIMER_PROF };
51   for (int i = 0; i < array_length (timers); i++)
52     {
53       TEST_COMPARE (getitimer (timers[i], &it), 0);
54 
55       /* No timer set, all value should be 0.  */
56       TEST_COMPARE (it.it_interval.tv_sec, 0);
57       TEST_COMPARE (it.it_interval.tv_usec, 0);
58       TEST_COMPARE (it.it_value.tv_sec, 0);
59       TEST_COMPARE (it.it_value.tv_usec, 0);
60 
61       it.it_interval.tv_sec = 10;
62       it.it_interval.tv_usec = 20;
63       TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
64 
65       TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 }, &it_old),
66 		    0);
67       /* ITIMER_REAL returns { 0, 0 } for single-shot timers, while
68 	 other timers returns setitimer value.  */
69       if (timers[i] == ITIMER_REAL)
70 	{
71 	  TEST_COMPARE (it_old.it_interval.tv_sec, 0);
72 	  TEST_COMPARE (it_old.it_interval.tv_usec, 0);
73 	}
74       else
75 	{
76 	  TEST_COMPARE (it_old.it_interval.tv_sec, 10);
77 	  /* Some systems might use a different precision for ITIMER_VIRTUAL
78 	     and ITIMER_IPROF and thus the value might be adjusted.  To avoid
79 	     trying to guess the resolution, we do not check it.  */
80 	}
81 
82       /* Create a periodic timer and check if the return value is the one
83 	 previously set.  */
84       it.it_interval.tv_sec = 10;
85       it.it_interval.tv_usec = 20;
86       it.it_value.tv_sec = 30;
87       it.it_value.tv_usec = 40;
88       TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
89 
90       TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 }, &it_old),
91 		    0);
92       TEST_COMPARE (it.it_interval.tv_sec, it_old.it_interval.tv_sec);
93       if (timers[i] == ITIMER_REAL)
94 	TEST_COMPARE (it.it_interval.tv_usec, it_old.it_interval.tv_usec);
95 
96       if (sizeof (time_t) == 4)
97 	continue;
98 
99       /* Same as before, but with a 64 bit time_t value.  */
100       it.it_interval.tv_sec = (time_t) 0x1ffffffffull;
101       it.it_interval.tv_usec = 20;
102       it.it_value.tv_sec = 0;
103       it.it_value.tv_usec = 0;
104 
105       /* Linux does not provide 64 bit time_t support for getitimer and
106 	 setitimer on architectures with 32 bit time_t support.  */
107       if (support_itimer_support_time64())
108 	{
109 	  TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
110 	  TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 },
111 				   &it_old),
112 			0);
113 	  /* ITIMER_REAL returns { 0, 0 } for single-sort timers, while other
114 	     timers returns setitimer value.  */
115 	  if (timers[i] == ITIMER_REAL)
116 	    {
117 	      TEST_COMPARE (it_old.it_interval.tv_sec, 0ull);
118 	      TEST_COMPARE (it_old.it_interval.tv_usec, 0);
119 	    }
120 	}
121       else
122 	{
123 	  TEST_COMPARE (setitimer (timers[i], &it, NULL), -1);
124 	  TEST_COMPARE (errno, EOVERFLOW);
125 	}
126 
127       /* Create a periodic timer and check if the return value is the one
128 	 previously set.  */
129       it.it_interval.tv_sec = (time_t) 0x1ffffffffull;
130       it.it_interval.tv_usec = 20;
131       it.it_value.tv_sec = 30;
132       it.it_value.tv_usec = 40;
133       if (support_itimer_support_time64())
134 	{
135 	  TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
136 
137 	  TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 },
138 				   &it_old),
139 			0);
140 	  if (timers[i] == ITIMER_REAL)
141 	    {
142 	      TEST_COMPARE (it.it_interval.tv_sec, it_old.it_interval.tv_sec);
143 	      TEST_COMPARE (it.it_interval.tv_usec, it_old.it_interval.tv_usec);
144 	    }
145 	}
146       else
147 	{
148 	  TEST_COMPARE (setitimer (timers[i], &it, NULL), -1);
149 	  TEST_COMPARE (errno, EOVERFLOW);
150 	}
151   }
152 
153   {
154     struct sigaction sa = { .sa_handler = alrm_handler, .sa_flags = 0 };
155     sigemptyset (&sa.sa_mask);
156     xsigaction (SIGALRM, &sa, NULL);
157   }
158 
159   /* Setup a timer to 0.1s and sleep for 1s and check to 3 signal handler
160      execution.  */
161   it.it_interval.tv_sec = 0;
162   it.it_interval.tv_usec = 100000;
163   it.it_value.tv_sec = 0;
164   it.it_value.tv_usec = 100000;
165 
166   /* Check ITIMER_VIRTUAL and ITIMER_PROF would require to generate load
167      and be subject to system load.  */
168   cnt = 0;
169   TEST_COMPARE (setitimer (ITIMER_REAL, &it, NULL), 0);
170   intr_sleep (1);
171   TEST_COMPARE (cnt, 3);
172   TEST_COMPARE (setitimer (ITIMER_REAL, &(struct itimerval) { 0 }, NULL), 0);
173 
174   return 0;
175 }
176 
177 #include <support/test-driver.c>
178