hurd: handle EINTR during critical sections

During critical sections, signal handling is deferred and thus RPCs return
EINTR, even if SA_RESTART is set. We thus have to restart the whole critical
section in that case.

This also adds HURD_CRITICAL_UNLOCK in the cases where one wants to
break the section in the middle.

1 files changed, 8 insertions, 1 deletions

diff --git a/sysdeps/mach/hurd/setitimer.c b/sysdeps/mach/hurd/setitimer.c
index e23e79a63e..4931644db5 100644
--- a/sysdeps/mach/hurd/setitimer.c
+++ b/sysdeps/mach/hurd/setitimer.c
@@ -339,6 +339,7 @@ __setitimer (enum __itimer_which which, const struct itimerval *new,
 	     struct itimerval *old)
 {
   void *crit;
+  int ret;
 
   switch (which)
     {
@@ -353,9 +354,15 @@ __setitimer (enum __itimer_which which, const struct itimerval *new,
       break;
     }
 
+retry:
   crit = _hurd_critical_section_lock ();
   __spin_lock (&_hurd_itimer_lock);
-  return setitimer_locked (new, old, crit, 0);
+  ret = setitimer_locked (new, old, crit, 0);
+  if (ret == -1 && errno == EINTR)
+    /* Got a signal while inside an RPC of the critical section, retry again */
+    goto retry;
+
+  return ret;
 }
 
 static void