More cleanups of the include files

- centralizing to simplify the -I's required to compile

src/include/storage/spin.h

@@ -0,0 +1,38 @@
+/*-------------------------------------------------------------------------
+ *
+ * spin.h--
+ *    synchronization routines
+ *
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ * $Id: spin.h,v 1.1 1996/08/28 01:58:33 scrappy Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef	SPIN_H
+#define SPIN_H
+
+#include "ipc.h"
+
+/* 
+ * two implementations of spin locks
+ *
+ * sequent, sparc, sun3: real spin locks. uses a TAS instruction; see
+ * src/storage/ipc/s_lock.c for details.
+ *
+ * default: fake spin locks using semaphores.  see spin.c
+ *
+ */
+
+typedef int SPINLOCK;
+
+extern bool CreateSpinlocks(IPCKey key);
+extern bool AttachSpinLocks(IPCKey key);
+extern bool InitSpinLocks(int init, IPCKey key);
+
+extern void SpinAcquire(SPINLOCK lock);
+extern void SpinRelease(SPINLOCK lock);
+extern bool SpinIsLocked(SPINLOCK lock);
+
+#endif	/* SPIN_H */