1*c9945492SAndroid Build Coastguard Worker #include <signal.h>
2*c9945492SAndroid Build Coastguard Worker
sigset(int sig,void (* handler)(int))3*c9945492SAndroid Build Coastguard Worker void (*sigset(int sig, void (*handler)(int)))(int)
4*c9945492SAndroid Build Coastguard Worker {
5*c9945492SAndroid Build Coastguard Worker struct sigaction sa, sa_old;
6*c9945492SAndroid Build Coastguard Worker sigset_t mask, mask_old;
7*c9945492SAndroid Build Coastguard Worker
8*c9945492SAndroid Build Coastguard Worker sigemptyset(&mask);
9*c9945492SAndroid Build Coastguard Worker if (sigaddset(&mask, sig) < 0)
10*c9945492SAndroid Build Coastguard Worker return SIG_ERR;
11*c9945492SAndroid Build Coastguard Worker
12*c9945492SAndroid Build Coastguard Worker if (handler == SIG_HOLD) {
13*c9945492SAndroid Build Coastguard Worker if (sigaction(sig, 0, &sa_old) < 0)
14*c9945492SAndroid Build Coastguard Worker return SIG_ERR;
15*c9945492SAndroid Build Coastguard Worker if (sigprocmask(SIG_BLOCK, &mask, &mask_old) < 0)
16*c9945492SAndroid Build Coastguard Worker return SIG_ERR;
17*c9945492SAndroid Build Coastguard Worker } else {
18*c9945492SAndroid Build Coastguard Worker sa.sa_handler = handler;
19*c9945492SAndroid Build Coastguard Worker sa.sa_flags = 0;
20*c9945492SAndroid Build Coastguard Worker sigemptyset(&sa.sa_mask);
21*c9945492SAndroid Build Coastguard Worker if (sigaction(sig, &sa, &sa_old) < 0)
22*c9945492SAndroid Build Coastguard Worker return SIG_ERR;
23*c9945492SAndroid Build Coastguard Worker if (sigprocmask(SIG_UNBLOCK, &mask, &mask_old) < 0)
24*c9945492SAndroid Build Coastguard Worker return SIG_ERR;
25*c9945492SAndroid Build Coastguard Worker }
26*c9945492SAndroid Build Coastguard Worker return sigismember(&mask_old, sig) ? SIG_HOLD : sa_old.sa_handler;
27*c9945492SAndroid Build Coastguard Worker }
28