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Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/lowlevellock.c')
-rw-r--r--nptl/sysdeps/unix/sysv/linux/lowlevellock.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/lowlevellock.c b/nptl/sysdeps/unix/sysv/linux/lowlevellock.c
new file mode 100644
index 0000000000..b80e15337f
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/lowlevellock.c
@@ -0,0 +1,140 @@
+/* low level locking for pthread library.  Generic futex-using version.
+   Copyright (C) 2003 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, 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>
+
+
+void
+__lll_lock_wait (int *futex, int val)
+{
+  do {
+      lll_futex_wait (futex, val+1);
+  } while ((val = __lll_add (futex, 1)) != 0);
+  *futex = 2;
+}
+hidden_proto (__lll_lock_wait)
+
+
+int
+__lll_timedlock_wait (int *futex, int val, const struct timespec *abstime)
+{
+  int err;
+
+  /* Reject invalid timeouts.  */
+  if (abstime->tv_nsec >= 1000000000)
+    return EINVAL;
+
+  do
+    {
+      struct timeval tv;
+      struct timespec rt;
+      int sec, nsec;
+
+      /* Get the current time.  */
+      __gettimeofday (&tv, NULL);
+
+      /* Compute relative timeout.  */
+      sec = abstime->tv_sec - tv.tv_sec;
+      nsec = abstime->tv_nsec - tv.tv_usec * 1000;
+      if (nsec < 0)
+	{
+	  nsec += 1000000000;
+	  --sec;
+	}
+
+      /* Already timed out?  */
+      err = -ETIMEDOUT;
+      if (sec < 0)
+	break;
+
+      /* Wait.  */
+      rt.tv_sec = sec;
+      rt.tv_nsec = nsec;
+      err = lll_futex_timed_wait (futex, val+1, &rt);
+    } while (err == 0 && (val = __lll_add (futex, 1)) != 0);
+
+  *futex = 2;
+  return -err;
+}
+hidden_proto (__lll_timedlock_wait)
+
+
+/* These don't get included in libc.so  */
+#ifdef IS_IN_libpthread
+int
+lll_unlock_wake_cb (int *futex)
+{
+  __lll_add (futex, 1);
+  return 0;
+}
+hidden_proto (lll_unlock_wake_cb)
+
+
+int
+__lll_timedwait_tid (int *tidp, const struct timespec *abstime)
+{
+  int tid;
+  int err = 0;
+
+  if (abstime == NULL || abstime->tv_nsec >= 1000000000)
+    return EINVAL;
+
+  /* Repeat until thread terminated.  */
+  while ((tid = *tidp) != 0)
+    {
+      struct timeval tv;
+      struct timespec rt;
+      int sec, nsec;
+
+      /* Get the current time.  */
+      __gettimeofday (&tv, NULL);
+
+      /* Compute relative timeout.  */
+      sec = abstime->tv_sec - tv.tv_sec;
+      nsec = abstime->tv_nsec - tv.tv_usec * 1000;
+      if (nsec < 0)
+	{
+	  nsec += 1000000000;
+	  --sec;
+	}
+
+      /* Already timed out?  */
+      err = -ETIMEDOUT;
+      if (sec < 0)
+	break;
+
+      /* Wait.  */
+      rt.tv_sec = sec;
+      rt.tv_nsec = nsec;
+
+      /* Wait until thread terminates.  */
+      err = lll_futex_timed_wait (tidp, tid, &rt);
+      if (err != 0)
+	break;
+    }
+
+  return -err;
+}
+
+hidden_proto (__lll_timedwait_tid)
+#endif