Imported Upstream version 4.0.0upstream/4.0.0

1 files changed, 74 insertions, 0 deletions

diff --git a/libcutl/cutl/static-ptr.hxx b/libcutl/cutl/static-ptr.hxx
new file mode 100644
index 0000000..6c907c8
--- /dev/null
+++ b/libcutl/cutl/static-ptr.hxx
@@ -0,0 +1,74 @@
+// file      : cutl/static-ptr.hxx
+// copyright : Copyright (c) 2009-2013 Code Synthesis Tools CC
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef CUTL_STATIC_PTR_HXX
+#define CUTL_STATIC_PTR_HXX
+
+#include <cstddef> // std::size_t
+
+namespace cutl
+{
+  // This class template implements Jerry Schwarz's static
+  // initialization technique commonly found in iostream
+  // implementations.
+  //
+  // The second template argument is used to make sure the
+  // instantiation of static_ptr is unique.
+  //
+  template <typename X, typename ID>
+  class static_ptr
+  {
+  public:
+    static_ptr ()
+    {
+      if (count_ == 0)
+        x_ = new X;
+
+      ++count_;
+    }
+
+    ~static_ptr ()
+    {
+      if (--count_ == 0)
+        delete x_;
+    }
+
+  private:
+    static_ptr (static_ptr const&);
+
+    static_ptr&
+    operator= (static_ptr const&);
+
+  public:
+    X*
+    operator-> () const
+    {
+      return x_;
+    }
+
+    X&
+    operator* () const
+    {
+      return *x_;
+    }
+
+    X*
+    get () const
+    {
+      return x_;
+    }
+
+  private:
+    static X* x_;
+    static std::size_t count_;
+  };
+
+  template <typename X, typename ID>
+  X* static_ptr<X, ID>::x_ = 0;
+
+  template <typename X, typename ID>
+  std::size_t static_ptr<X, ID>::count_ = 0;
+}
+
+#endif // CUTL_STATIC_PTR_HXX