Add missing lowlevelrobustlock.c

Signed-off-by: Khem Raj <raj.khem@gmail.com>

libpthread/nptl/sysdeps/unix/sysv/linux/lowlevelrobustlock.c

@@ -0,0 +1,114 @@
+/* Copyright (C) 2006, 2007 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jakub Jelinek <jakub@redhat.com>, 2006.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <sysdep.h>
+#include <lowlevellock.h>
+#include <sys/time.h>
+#include <pthreadP.h>
+
+
+int
+__lll_robust_lock_wait (int *futex, int private)
+{
+  int oldval = *futex;
+  int tid = THREAD_GETMEM (THREAD_SELF, tid);
+
+  /* If the futex changed meanwhile try locking again.  */
+  if (oldval == 0)
+    goto try;
+
+  do
+    {
+      if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0))
+	return oldval;
+
+      int newval = oldval | FUTEX_WAITERS;
+      if (oldval != newval
+	  && atomic_compare_and_exchange_bool_acq (futex, newval, oldval))
+	continue;
+
+      lll_futex_wait (futex, newval, private);
+
+    try:
+      ;
+    }
+  while ((oldval = atomic_compare_and_exchange_val_acq (futex,
+							tid | FUTEX_WAITERS,
+							0)) != 0);
+  return 0;
+}
+
+
+int
+__lll_robust_timedlock_wait (int *futex, const struct timespec *abstime,
+			     int private)
+{
+  /* Reject invalid timeouts.  */
+  if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)
+    return EINVAL;
+
+  int tid = THREAD_GETMEM (THREAD_SELF, tid);
+  int oldval = *futex;
+
+  /* If the futex changed meanwhile try locking again.  */
+  if (oldval == 0)
+    goto try;
+
+  do
+    {
+      struct timeval tv;
+      struct timespec rt;
+
+      /* Get the current time.  */
+      (void) __gettimeofday (&tv, NULL);
+
+      /* Compute relative timeout.  */
+      rt.tv_sec = abstime->tv_sec - tv.tv_sec;
+      rt.tv_nsec = abstime->tv_nsec - tv.tv_usec * 1000;
+      if (rt.tv_nsec < 0)
+	{
+	  rt.tv_nsec += 1000000000;
+	  --rt.tv_sec;
+	}
+
+      /* Already timed out?  */
+      if (rt.tv_sec < 0)
+	return ETIMEDOUT;
+
+      /* Wait.  */
+      if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0))
+	return oldval;
+
+      int newval = oldval | FUTEX_WAITERS;
+      if (oldval != newval
+	  && atomic_compare_and_exchange_bool_acq (futex, newval, oldval))
+	continue;
+
+      lll_futex_timed_wait (futex, newval, &rt, private);
+
+    try:
+      ;
+    }
+  while ((oldval = atomic_compare_and_exchange_val_acq (futex,
+							tid | FUTEX_WAITERS,
+							0)) != 0);
+
+  return 0;
+}