1 /* Test of correct simulation for uc->uc_link in a signal handler. */
2 
3 #include <assert.h>
4 #include <signal.h>
5 #include <stdio.h>
6 #include <ucontext.h>
7 
sighandler(int sig,siginfo_t * sip,ucontext_t * ucp)8 static void sighandler(int sig, siginfo_t *sip, ucontext_t *ucp)
9 {
10    ucontext_t uc2;
11 
12    /* Current uc_link value has to be equal to ucp. */
13    getcontext(&uc2);
14    assert(uc2.uc_link == ucp);
15 }
16 
main(void)17 int main(void)
18 {
19    ucontext_t uc;
20    struct sigaction sa;
21 
22    /* Current uc_link value has to be NULL. */
23    if (getcontext(&uc)) {
24       perror("getcontext");
25       return 1;
26    }
27    assert(!uc.uc_link);
28 
29    sa.sa_handler = sighandler;
30    sa.sa_flags = SA_SIGINFO;
31    if (sigfillset(&sa.sa_mask)) {
32       perror("sigfillset");
33       return 1;
34    }
35    if (sigaction(SIGUSR1, &sa, NULL)) {
36       perror("sigaction");
37       return 1;
38    }
39 
40    raise(SIGUSR1);
41 
42    /* Current uc_link value has to be NULL. */
43    getcontext(&uc);
44    assert(!uc.uc_link);
45 
46    return 0;
47 }
48 
49