2 files changed, 92 insertions, 0 deletions
diff --git a/libcult/cult/mm/arch/generic/counter.hxx b/libcult/cult/mm/arch/generic/counter.hxx
new file mode 100644
index 0000000..6a26759
--- /dev/null
+++ b/libcult/cult/mm/arch/generic/counter.hxx
@@ -0,0 +1,45 @@
+// file      : cult/mm/arch/generic/counter.hxx
+// author    : Boris Kolpackov <boris@kolpackov.net>
+// copyright : Copyright (c) 2005-2010 Boris Kolpackov
+// license   : GNU GPL v2 + exceptions; see accompanying LICENSE file
+
+#ifndef CULT_MM_ARCH_GENERIC_COUNTER_HXX
+#define CULT_MM_ARCH_GENERIC_COUNTER_HXX
+
+#include <cult/types/fundamental.hxx>
+#include <cult/sched/spin.hxx>
+
+namespace Cult
+{
+  namespace MM
+  {
+    class Counter: public NonCopyable
+    {
+    public:
+      Counter ();
+
+      // After failure assume the counter has its old value.
+      //
+      Void
+      inc_ref ();
+
+
+      // After failure assume the counter has its new value.
+      //
+      Boolean
+      dec_ref ();
+
+
+      Size
+      count () const;
+
+    private:
+      Size value_;
+      mutable Sched::Spin spin_;
+    };
+  }
+}
+
+#include <cult/mm/arch/generic/counter.ixx>
+
+#endif  // CULT_MM_ARCH_GENERIC_COUNTER_HXX
diff --git a/libcult/cult/mm/arch/generic/counter.ixx b/libcult/cult/mm/arch/generic/counter.ixx
new file mode 100644
index 0000000..648d28a
--- /dev/null
+++ b/libcult/cult/mm/arch/generic/counter.ixx
@@ -0,0 +1,47 @@
+// file      : cult/mm/arch/generic/counter.ixx
+// author    : Boris Kolpackov <boris@kolpackov.net>
+// copyright : Copyright (c) 2005-2010 Boris Kolpackov
+// license   : GNU GPL v2 + exceptions; see accompanying LICENSE file
+
+#include <cult/sched/lock.hxx>
+
+namespace Cult
+{
+  namespace MM
+  {
+    inline
+    Counter::
+    Counter ()
+        : value_ (1)
+    {
+    }
+
+    inline
+    Void Counter::
+    inc_ref ()
+    {
+      Sched::Lock l (spin_);
+
+      ++value_;
+    }
+
+    inline
+    Boolean Counter::
+    dec_ref ()
+    {
+      Sched::Lock l (spin_);
+
+      return --value_ == 0;
+
+    }
+
+    inline
+    Size Counter::
+    count () const
+    {
+      Sched::Lock l (spin_);
+
+      return value_;
+    }
+  }
+}