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Elixir Cross Referencer

#include <signal.h>
#include <errno.h>
#include <string.h>
#include "syscall.h"
#include "pthread_impl.h"
#include "libc.h"
#include "lock.h"
#include "ksigaction.h"

static int unmask_done;
static unsigned long handler_set[_NSIG/(8*sizeof(long))];

void __get_handler_set(sigset_t *set)
	memcpy(set, handler_set, sizeof handler_set);

volatile int __eintr_valid_flag;

int __libc_sigaction(int sig, const struct sigaction *restrict sa, struct sigaction *restrict old)
	struct k_sigaction ksa, ksa_old;
	if (sa) {
		if ((uintptr_t)sa->sa_handler > 1UL) {

			/* If pthread_create has not yet been called,
			 * implementation-internal signals might not
			 * yet have been unblocked. They must be
			 * unblocked before any signal handler is
			 * installed, so that an application cannot
			 * receive an illegal sigset_t (with them
			 * blocked) as part of the ucontext_t passed
			 * to the signal handler. */
			if (!libc.threaded && !unmask_done) {
				__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK,
					SIGPT_SET, 0, _NSIG/8);
				unmask_done = 1;

			if (!(sa->sa_flags & SA_RESTART)) {
				a_store(&__eintr_valid_flag, 1);
		ksa.handler = sa->sa_handler;
		ksa.flags = sa->sa_flags;
		ksa.flags |= SA_RESTORER;
		ksa.restorer = (sa->sa_flags & SA_SIGINFO) ? __restore_rt : __restore;
		memcpy(&ksa.mask, &sa->sa_mask, _NSIG/8);
	int r = __syscall(SYS_rt_sigaction, sig, sa?&ksa:0, old?&ksa_old:0, _NSIG/8);
	if (old && !r) {
		old->sa_handler = ksa_old.handler;
		old->sa_flags = ksa_old.flags;
		memcpy(&old->sa_mask, &ksa_old.mask, _NSIG/8);
	return __syscall_ret(r);

int __sigaction(int sig, const struct sigaction *restrict sa, struct sigaction *restrict old)
	unsigned long set[_NSIG/(8*sizeof(long))];

	if (sig-32U < 3 || sig-1U >= _NSIG-1) {
		errno = EINVAL;
		return -1;

	/* Doing anything with the disposition of SIGABRT requires a lock,
	 * so that it cannot be changed while abort is terminating the
	 * process and so any change made by abort can't be observed. */
	if (sig == SIGABRT) {
	int r = __libc_sigaction(sig, sa, old);
	if (sig == SIGABRT) {
	return r;

weak_alias(__sigaction, sigaction);