summary refs log tree commit diff
path: root/sysdeps/generic/machine-lock.h
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/generic/machine-lock.h')
-rw-r--r--sysdeps/generic/machine-lock.h64
1 files changed, 64 insertions, 0 deletions
diff --git a/sysdeps/generic/machine-lock.h b/sysdeps/generic/machine-lock.h
new file mode 100644
index 0000000000..3776bb0049
--- /dev/null
+++ b/sysdeps/generic/machine-lock.h
@@ -0,0 +1,64 @@
+/* Machine-specific definition for spin locks.  Stub version.
+   Copyright (C) 1994, 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#ifndef _MACHINE_LOCK_H
+#define	_MACHINE_LOCK_H
+
+/* The type of a spin lock variable.  */
+
+typedef volatile int __spin_lock_t;
+
+/* Value to initialize `__spin_lock_t' variables to.  */
+
+#define	__SPIN_LOCK_INITIALIZER	0
+
+
+#ifndef _EXTERN_INLINE
+#define _EXTERN_INLINE extern __inline
+#endif
+
+/* Unlock LOCK.  */
+
+_EXTERN_INLINE void
+__spin_unlock (__spin_lock_t *__lock)
+{
+  *__lock = 0;
+}
+
+/* Try to lock LOCK; return nonzero if we locked it, zero if another has.  */
+
+_EXTERN_INLINE int
+__spin_try_lock (__spin_lock_t *__lock)
+{
+  if (*__lock)
+    return 0;
+  *__lock = 1;
+  return 1;
+}
+
+/* Return nonzero if LOCK is locked.  */
+
+_EXTERN_INLINE int
+__spin_lock_locked (__spin_lock_t *__lock)
+{
+  return *__lock != 0;
+}
+
+
+#endif /* machine-lock.h */