WebKit/chromium/public/WebPrivatePtr.h
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebKit/chromium/public/WebPrivatePtr.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2010 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef WebPrivatePtr_h
+#define WebPrivatePtr_h
+
+#if WEBKIT_IMPLEMENTATION
+#include <wtf/PassRefPtr.h>
+#endif
+
+namespace WebKit {
+
+// This class is an implementation detail of the WebKit API.  It exists
+// to help simplify the implementation of WebKit interfaces that merely
+// wrap a reference counted WebCore class.
+template <typename T>
+class WebPrivatePtr {
+public:
+    WebPrivatePtr() : m_ptr(0) { }
+    ~WebPrivatePtr() { WEBKIT_ASSERT(!m_ptr); }
+
+    bool isNull() const { return !m_ptr; }
+
+#if WEBKIT_IMPLEMENTATION
+    WebPrivatePtr(const PassRefPtr<T>& prp)
+        : m_ptr(prp.releaseRef())
+    {
+    }
+
+    void reset()
+    {
+        assign(0);
+    }
+
+    WebPrivatePtr<T>& operator=(const WebPrivatePtr<T>& other)
+    {
+        T* p = other.m_ptr;
+        if (p)
+            p->ref();
+        assign(p);
+        return *this;
+    }
+
+    WebPrivatePtr<T>& operator=(const PassRefPtr<T>& prp)
+    {
+        assign(prp.releaseRef());
+        return *this;
+    }
+
+    T* get() const
+    {
+        return m_ptr;
+    }
+
+    T* operator->() const
+    {
+        ASSERT(m_ptr);
+        return m_ptr;
+    }
+#endif
+
+private:
+#if WEBKIT_IMPLEMENTATION
+    void assign(T* p)
+    {
+        // p is already ref'd for us by the caller
+        if (m_ptr)
+            m_ptr->deref();
+        m_ptr = p;
+    }
+#endif
+
+    T* m_ptr;
+};
+
+} // namespace WebKit
+
+#endif