-#include <stdlib.h>
#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"
-void __restore(), __restore_rt();
+static int unmask_done;
+static unsigned long handler_set[_NSIG/(8*sizeof(long))];
-int __libc_sigaction(int sig, const struct sigaction *sa, struct sigaction *old)
+void __get_handler_set(sigset_t *set)
{
- struct {
- void *handler;
- unsigned long flags;
- void (*restorer)(void);
- sigset_t mask;
- } ksa, kold;
- long pksa=0, pkold=0;
+ 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) {
+ a_or_l(handler_set+(sig-1)/(8*sizeof(long)),
+ 1UL<<(sig-1)%(8*sizeof(long)));
+
+ /* 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 | SA_RESTORER;
ksa.restorer = (sa->sa_flags & SA_SIGINFO) ? __restore_rt : __restore;
- ksa.mask = sa->sa_mask;
- pksa = (long)&ksa;
+ memcpy(&ksa.mask, &sa->sa_mask, _NSIG/8);
}
- if (old) pkold = (long)&kold;
- if (syscall(SYS_rt_sigaction, sig, pksa, pkold, 8))
- return -1;
- if (old) {
- old->sa_handler = kold.handler;
- old->sa_flags = kold.flags;
- old->sa_mask = kold.mask;
+ 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 0;
+ return __syscall_ret(r);
}
-int __sigaction(int sig, const struct sigaction *sa, struct sigaction *old)
+int __sigaction(int sig, const struct sigaction *restrict sa, struct sigaction *restrict old)
{
- if (sig == SIGCANCEL || sig == SIGSYSCALL) {
+ unsigned long set[_NSIG/(8*sizeof(long))];
+
+ if (sig-32U < 3 || sig-1U >= _NSIG-1) {
errno = EINVAL;
return -1;
}
- return __libc_sigaction(sig, sa, old);
+
+ /* 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) {
+ __block_all_sigs(&set);
+ LOCK(__abort_lock);
+ }
+ int r = __libc_sigaction(sig, sa, old);
+ if (sig == SIGABRT) {
+ UNLOCK(__abort_lock);
+ __restore_sigs(&set);
+ }
+ return r;
}
weak_alias(__sigaction, sigaction);