Reference counting and smart pointers.

1 files changed, 130 insertions, 0 deletions

diff --git a/src/object.cpp b/src/object.cpp
new file mode 100644
index 00000000..481a3564
--- /dev/null
+++ b/src/object.cpp
@@ -0,0 +1,130 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2005 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of
+// the License, or (at your option) any later version.
+//
+// This program 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
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+//
+
+#include "vmime/types.hpp"
+#include "vmime/object.hpp"
+
+#include <algorithm>  // std::find
+#include <sstream>    // std::ostringstream
+#include <stdexcept>  // std::runtime_error
+
+
+namespace vmime
+{
+
+
+object::object()
+	: m_strongCount(0)
+{
+}
+
+
+object::object(const object&)
+	: m_strongCount(0)
+{
+	// Not used
+}
+
+
+object::~object()
+{
+	for (std::vector <utility::weak_ref_base*>::iterator
+	     it = m_weakRefs.begin() ; it != m_weakRefs.end() ; ++it)
+	{
+		(*it)->notifyObjectDestroyed();
+	}
+
+#if VMIME_DEBUG
+	if (m_strongCount != 0)
+	{
+		std::ostringstream oss;
+		oss << "ERROR: Deleting object and strong count != 0."
+		    << " (" << __FILE__ << ", line " << __LINE__ << ")" << std::endl;
+
+		throw std::runtime_error(oss.str());
+	}
+#endif // VMIME_DEBUG
+}
+
+
+void object::addStrong() const
+{
+	++m_strongCount;
+}
+
+
+void object::addWeak(utility::weak_ref_base* w) const
+{
+	m_weakRefs.push_back(w);
+}
+
+
+void object::releaseStrong() const
+{
+	if (--m_strongCount == 0)
+		delete this;
+}
+
+
+void object::releaseWeak(utility::weak_ref_base* w) const
+{
+	std::vector <utility::weak_ref_base*>::iterator
+		it = std::find(m_weakRefs.begin(), m_weakRefs.end(), w);
+
+	if (it != m_weakRefs.end())
+		m_weakRefs.erase(it);
+#if VMIME_DEBUG
+	else
+	{
+		std::ostringstream oss;
+		oss << "ERROR: weak ref does not exist anymore!"
+		    << " (" << __FILE__ << ", line " << __LINE__ << ")" << std::endl;
+
+		throw std::runtime_error(oss.str());
+	}
+#endif // VMIME_DEBUG
+}
+
+
+ref <object> object::thisRef()
+{
+	return ref <object>::fromPtr(this);
+}
+
+
+ref <const object> object::thisRef() const
+{
+	return ref <const object>::fromPtr(this);
+}
+
+
+weak_ref <object> object::thisWeakRef()
+{
+	return weak_ref <object>(thisRef());
+}
+
+
+weak_ref <const object> object::thisWeakRef() const
+{
+	return weak_ref <const object>(thisRef());
+}
+
+
+} // vmime
+