added util/refptr, tests/Initial.jtl, parser/parser.h, c_statement to grammar

git-svn-id: svn://anubis/jtlc/trunk@7 f5bc74b8-7b62-4e90-9214-7121d538519f

util/refptr.h

@@ -0,0 +1,106 @@
+/*
+ * Author: Josh Holtrop
+ * Purpose: Provide a reference-counting "pointer" object for C++
+ */
+
+#ifndef REFPTR_H
+#define REFPTR_H REFPTR_H
+
+#include <stdlib.h>             /* NULL */
+
+template <typename T>
+class refptr
+{
+    public:
+        refptr<T>();
+        refptr<T>(T * ptr);
+        refptr<T>(const refptr<T> & orig);
+        refptr<T> & operator=(const refptr<T> & orig);
+        refptr<T> & operator=(T * ptr);
+        ~refptr<T>();
+        T & operator*() const;
+        T * operator->() const;
+        bool isNull() const { return m_ptr == NULL; }
+
+    private:
+        void cloneFrom(const refptr<T> & orig);
+        void destroy();
+
+        T * m_ptr;
+        int * m_refCount;
+};
+
+template <typename T> refptr<T>::refptr()
+{
+    m_ptr = NULL;
+    m_refCount = NULL;
+}
+
+template <typename T> refptr<T>::refptr(T * ptr)
+{
+    m_ptr = ptr;
+    m_refCount = new int;
+    *m_refCount = 1;
+}
+
+template <typename T> refptr<T>::refptr(const refptr<T> & orig)
+{
+    cloneFrom(orig);
+}
+
+template <typename T> refptr<T> & refptr<T>::operator=(const refptr<T> & orig)
+{
+    destroy();
+    cloneFrom(orig);
+    return *this;
+}
+
+template <typename T> refptr<T> & refptr<T>::operator=(T * ptr)
+{
+    destroy();
+    m_ptr = ptr;
+    m_refCount = new int;
+    *m_refCount = 1;
+    return *this;
+}
+
+template <typename T> void refptr<T>::cloneFrom(const refptr<T> & orig)
+{
+    this->m_ptr = orig.m_ptr;
+    this->m_refCount = orig.m_refCount;
+    if (m_refCount != NULL)
+        (*m_refCount)++;
+}
+
+template <typename T> refptr<T>::~refptr()
+{
+    destroy();
+}
+
+template <typename T> void refptr<T>::destroy()
+{
+    if (m_refCount != NULL)
+    {
+        if (*m_refCount <= 1)
+        {
+            delete m_ptr;
+            delete m_refCount;
+        }
+        else
+        {
+            (*m_refCount)--;
+        }
+    }
+}
+
+template <typename T> T & refptr<T>::operator*() const
+{
+    return *m_ptr;
+}
+
+template <typename T> T * refptr<T>::operator->() const
+{
+    return m_ptr;
+}
+
+#endif