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9#include <stdarg.h>
10#include <stdint.h>
11#include <stdio.h>
12#include <stdlib.h>
13#include <unistd.h>
14#include <errno.h>
15#include <pthread.h>
16#include <string.h>
17#include <signal.h>
18#include <time.h>
19#include <sys/time.h>
20
21static void error1(const char *filename, int line, const char *fmt, ...)
22{
23 va_list ap;
24 va_start(ap, fmt);
25 fprintf(stderr, "%s:%d: ", filename, line);
26 vfprintf(stderr, fmt, ap);
27 fprintf(stderr, "\n");
28 va_end(ap);
29 exit(1);
30}
31
32static int __chk_error(const char *filename, int line, int ret)
33{
34 if (ret < 0) {
35 error1(filename, line, "%m (ret=%d, errno=%d/%s)",
36 ret, errno, strerror(errno));
37 }
38 return ret;
39}
40
41#define error(fmt, ...) error1(__FILE__, __LINE__, fmt, ## __VA_ARGS__)
42
43#define chk_error(ret) __chk_error(__FILE__, __LINE__, (ret))
44
45
46
47
48typedef struct ThreadJob ThreadJob;
49
50struct ThreadJob {
51 int number;
52 int sleep;
53 int count;
54};
55
56static pthread_t *threads;
57static int max_threads = 10;
58__thread int signal_count;
59int total_signal_count;
60
61static void *background_thread_func(void *arg)
62{
63 ThreadJob *job = (ThreadJob *) arg;
64
65 printf("thread%d: started\n", job->number);
66 while (total_signal_count < job->count) {
67 usleep(job->sleep);
68 }
69 printf("thread%d: saw %d alarms from %d\n", job->number,
70 signal_count, total_signal_count);
71 return NULL;
72}
73
74static void spawn_threads(void)
75{
76 int i;
77 threads = calloc(sizeof(pthread_t), max_threads);
78
79 for (i = 0; i < max_threads; i++) {
80 ThreadJob *job = calloc(sizeof(ThreadJob), 1);
81 job->number = i;
82 job->sleep = i * 1000;
83 job->count = i * 100;
84 pthread_create(threads + i, NULL, background_thread_func, job);
85 }
86}
87
88static void close_threads(void)
89{
90 int i;
91 for (i = 0; i < max_threads; i++) {
92 pthread_join(threads[i], NULL);
93 }
94 free(threads);
95 threads = NULL;
96}
97
98static void sig_alarm(int sig, siginfo_t *info, void *puc)
99{
100 if (sig != SIGRTMIN) {
101 error("unexpected signal");
102 }
103 signal_count++;
104 __atomic_fetch_add(&total_signal_count, 1, __ATOMIC_SEQ_CST);
105}
106
107static void test_signals(void)
108{
109 struct sigaction act;
110 struct itimerspec it;
111 timer_t tid;
112 struct sigevent sev;
113
114
115 act.sa_sigaction = sig_alarm;
116 sigemptyset(&act.sa_mask);
117 act.sa_flags = SA_SIGINFO;
118 chk_error(sigaction(SIGRTMIN, &act, NULL));
119
120
121 sev.sigev_notify = SIGEV_SIGNAL;
122 sev.sigev_signo = SIGRTMIN;
123 sev.sigev_value.sival_ptr = &tid;
124 chk_error(timer_create(CLOCK_REALTIME, &sev, &tid));
125
126 it.it_interval.tv_sec = 0;
127 it.it_interval.tv_nsec = 1000000;
128 it.it_value.tv_sec = 0;
129 it.it_value.tv_nsec = 1000000;
130 chk_error(timer_settime(tid, 0, &it, NULL));
131
132 spawn_threads();
133
134 do {
135 usleep(1000);
136 } while (total_signal_count < 2000);
137
138 printf("shutting down after: %d signals\n", total_signal_count);
139
140 close_threads();
141
142 chk_error(timer_delete(tid));
143}
144
145int main(int argc, char **argv)
146{
147 test_signals();
148 return 0;
149}
150