Make sure helper thread has all signals blocked.

This commit is contained in:
Ulrich Drepper 2004-04-20 02:52:14 +00:00
parent 2282308567
commit fa0e226b38

View File

@ -32,6 +32,14 @@
static void *
timer_sigev_thread (void *arg)
{
/* The parent thread has all signals blocked. This is a bit
surprising for user code, although valid. We unblock all
signals. */
sigset_t ss;
sigemptyset (&ss);
INTERNAL_SYSCALL_DECL (err);
INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &ss, NULL, _NSIG / 8);
struct timer *tk = (struct timer *) arg;
/* Call the user-provided function. */
@ -45,16 +53,10 @@ timer_sigev_thread (void *arg)
static void *
timer_helper_thread (void *arg)
{
/* Block all signals. We will only wait for the signal the kernel
will send. */
/* Wait for the SIGTIMER signal and none else. */
sigset_t ss;
sigemptyset (&ss);
sigaddset (&ss, SIGTIMER);
/* SIGTIMER is the same signal as SIGCANCEL and it is therefore
unblocked so far. Block it for this thread, we handle
cancellation explicitly. */
INTERNAL_SYSCALL_DECL (err);
INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_BLOCK, &ss, NULL, _NSIG / 8);
/* Endless loop of waiting for signals. The loop is only ended when
the thread is canceled. */
@ -119,6 +121,14 @@ __start_helper_thread (void)
(void) pthread_attr_init (&attr);
(void) pthread_attr_setstacksize (&attr, PTHREAD_STACK_MIN);
/* Block all signals in the helper thread. To do this thoroughly we
temporarily have to block all signals here. */
sigset_t ss;
sigset_t oss;
sigfillset (&ss);
INTERNAL_SYSCALL_DECL (err);
INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &ss, &oss, _NSIG / 8);
/* Create the helper thread for this timer. */
pthread_t th;
int res = pthread_create (&th, &attr, timer_helper_thread, NULL);
@ -126,6 +136,10 @@ __start_helper_thread (void)
/* We managed to start the helper thread. */
__helper_tid = ((struct pthread *) th)->tid;
/* Restore the signal mask. */
INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &oss, NULL,
_NSIG / 8);
/* No need for the attribute anymore. */
(void) pthread_attr_destroy (&attr);