Imported Upstream version 1.49.0upstream/1.49.0

1 files changed, 36 insertions, 0 deletions

diff --git a/tools/quickbook/src/intrusive_base.hpp b/tools/quickbook/src/intrusive_base.hpp
new file mode 100644
index 0000000000..702c13d0b9
--- /dev/null
+++ b/tools/quickbook/src/intrusive_base.hpp
@@ -0,0 +1,36 @@
+/*=============================================================================
+    Copyright (c) 2011 Daniel James
+
+    Use, modification and distribution is subject to the Boost Software
+    License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+    http://www.boost.org/LICENSE_1_0.txt)
+=============================================================================*/
+
+#if !defined(BOOST_QUICKBOOK_INTRUSIVE_BASE_HPP)
+#define BOOST_QUICKBOOK_INTRUSIVE_BASE_HPP
+
+namespace quickbook
+{
+    //
+    // instructive_base
+    //
+
+    template <typename T>
+    struct intrusive_base
+    {
+        intrusive_base() : ref_count_(0) {}
+        intrusive_base(intrusive_base const&) : ref_count_(0) {}
+        intrusive_base& operator=(intrusive_base const&) { return *this; }
+        ~intrusive_base() { assert(!ref_count_); }
+
+        friend void intrusive_ptr_add_ref(T* ptr)
+            { ++ptr->ref_count_; }
+
+        friend void intrusive_ptr_release(T* ptr)
+            { if(--ptr->ref_count_ == 0) delete ptr; }
+    private:
+        unsigned ref_count_;
+    };
+}
+
+#endif