Split timed-wait functions out of nptl/lowlevellock.c.

1 files changed, 59 insertions, 0 deletions

diff --git a/nptl/lll_timedlock_wait.c b/nptl/lll_timedlock_wait.c
new file mode 100644
index 0000000000..37cf08345b
--- /dev/null
+++ b/nptl/lll_timedlock_wait.c
@@ -0,0 +1,59 @@
+/* Timed low level locking for pthread library.  Generic futex-using version.
+   Copyright (C) 2003-2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <atomic.h>
+#include <errno.h>
+#include <lowlevellock.h>
+#include <sys/time.h>
+
+
+int
+__lll_timedlock_wait (int *futex, const struct timespec *abstime, int private)
+{
+  /* Reject invalid timeouts.  */
+  if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)
+    return EINVAL;
+
+  /* Try locking.  */
+  while (atomic_exchange_acq (futex, 2) != 0)
+    {
+      struct timeval tv;
+
+      /* Get the current time.  */
+      (void) __gettimeofday (&tv, NULL);
+
+      /* Compute relative timeout.  */
+      struct timespec rt;
+      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;
+        }
+
+      if (rt.tv_sec < 0)
+        return ETIMEDOUT;
+
+      /* If *futex == 2, wait until woken or timeout.  */
+      lll_futex_timed_wait (futex, 2, &rt, private);
+    }
+
+  return 0;
+}