1#include <signal.h> 2#include <errno.h> 3#include <string.h> 4#include "syscall.h" 5#include "pthread_impl.h" 6#include "libc.h" 7#include "ksigaction.h" 8 9static int unmask_done; 10static unsigned long handler_set[_NSIG/(8*sizeof(long))]; 11 12void __get_handler_set(sigset_t *set) 13{ 14 memcpy(set, handler_set, sizeof handler_set); 15} 16 17int __libc_sigaction(int sig, const struct sigaction *restrict sa, struct sigaction *restrict old) 18{ 19 struct k_sigaction ksa, ksa_old; 20 if (sa) { 21 if ((uintptr_t)sa->sa_handler > 1UL) { 22 a_or_l(handler_set+(sig-1)/(8*sizeof(long)), 23 1UL<<(sig-1)%(8*sizeof(long))); 24 25 /* If pthread_create has not yet been called, 26 * implementation-internal signals might not 27 * yet have been unblocked. They must be 28 * unblocked before any signal handler is 29 * installed, so that an application cannot 30 * receive an illegal sigset_t (with them 31 * blocked) as part of the ucontext_t passed 32 * to the signal handler. */ 33 if (!libc.threaded && !unmask_done) { 34 __syscall(SYS_rt_sigprocmask, SIG_UNBLOCK, 35 SIGPT_SET, 0, _NSIG/8); 36 unmask_done = 1; 37 } 38 } 39 ksa.handler = sa->sa_handler; 40 ksa.flags = sa->sa_flags | SA_RESTORER; 41 ksa.restorer = (sa->sa_flags & SA_SIGINFO) ? __restore_rt : __restore; 42 memcpy(&ksa.mask, &sa->sa_mask, sizeof ksa.mask); 43 } 44 if (syscall(SYS_rt_sigaction, sig, sa?&ksa:0, old?&ksa_old:0, sizeof ksa.mask)) 45 return -1; 46 if (old) { 47 old->sa_handler = ksa_old.handler; 48 old->sa_flags = ksa_old.flags; 49 memcpy(&old->sa_mask, &ksa_old.mask, sizeof ksa_old.mask); 50 } 51 return 0; 52} 53 54int __sigaction(int sig, const struct sigaction *restrict sa, struct sigaction *restrict old) 55{ 56 if (sig-32U < 3 || sig-1U >= _NSIG-1) { 57 errno = EINVAL; 58 return -1; 59 } 60 return __libc_sigaction(sig, sa, old); 61} 62 63weak_alias(__sigaction, sigaction); 64