1/* Copyright (C) 2003-2024 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <pthread.h>
19#include <signal.h>
20#include <unistd.h>
21#include <support/xthread.h>
22#include <support/xsignal.h>
23#include <support/xthread.h>
24
25
26static int the_sig;
27
28
29static void
30eintr_handler (int sig)
31{
32 if (sig != the_sig)
33 {
34 /* empty if statement avoids warn unused result */
35 if (write (STDOUT_FILENO,
36 "eintr_handler: signal number wrong\n", 35) < 35) {};
37 _exit (1);
38 }
39 if (write (STDOUT_FILENO, ".", 1)) {/* Avoid warn unused result */};
40}
41
42
43static void *
44eintr_source (void *arg)
45{
46 struct timespec ts = { .tv_sec = 0, .tv_nsec = 500000 };
47
48 if (arg == NULL)
49 {
50 sigset_t ss;
51 sigemptyset (&ss);
52 sigaddset (&ss, the_sig);
53 xpthread_sigmask (SIG_BLOCK, set: &ss, NULL);
54 }
55
56 while (1)
57 {
58 if (arg != NULL)
59 pthread_kill (threadid: *(pthread_t *) arg, signo: the_sig);
60 else
61 kill (pid: getpid (), sig: the_sig);
62
63 nanosleep (requested_time: &ts, NULL);
64 }
65
66 /* NOTREACHED */
67 return NULL;
68}
69
70
71static void
72setup_eintr (int sig, pthread_t *thp)
73{
74 struct sigaction sa;
75 sigemptyset (&sa.sa_mask);
76 sa.sa_flags = 0;
77 sa.sa_handler = eintr_handler;
78 if (sigaction (sig: sig, act: &sa, NULL) != 0)
79 {
80 puts (s: "setup_eintr: sigaction failed");
81 exit (1);
82 }
83 the_sig = sig;
84
85 /* Create the thread which will fire off the signals. */
86 xpthread_create (NULL, thread_func: eintr_source, closure: thp);
87}
88

source code of glibc/sysdeps/pthread/eintr.c