From cbf5c721f42e1c4b2caaf5f55395c68639783b28 Mon Sep 17 00:00:00 2001
From: David Capello <davidcapello@gmail.com>
Date: Thu, 17 Mar 2011 23:28:33 -0300
Subject: [PATCH] Add UniquePtr class.

---
 src/base/unique_ptr.h            | 84 +++++++++++++++++++++++++++++
 src/base/unique_ptr_unittest.cpp | 91 ++++++++++++++++++++++++++++++++
 2 files changed, 175 insertions(+)
 create mode 100644 src/base/unique_ptr.h
 create mode 100644 src/base/unique_ptr_unittest.cpp

diff --git a/src/base/unique_ptr.h b/src/base/unique_ptr.h
new file mode 100644
index 000000000..48ea7dfd2
--- /dev/null
+++ b/src/base/unique_ptr.h
@@ -0,0 +1,84 @@
+// ASE base library
+// Copyright (C) 2001-2011  David Capello
+//
+// This source file is ditributed under a BSD-like license, please
+// read LICENSE.txt for more information.
+
+#ifndef BASE_UNIQUE_PTR_H_INCLUDED
+#define BASE_UNIQUE_PTR_H_INCLUDED
+
+#include "base/disable_copying.h"
+
+// Default deleter used by unique pointers (it calls "delete" operator).
+template<class T>
+class DefaultUniquePtrDeleter
+{
+public:
+  void operator()(T* ptr)
+  {
+    delete ptr;
+  }
+};
+
+// Keeps the life time of the pointee object between the scope of the
+// UniquePtr instance.
+template<class T, class D = DefaultUniquePtrDeleter<T> >
+class UniquePtr
+{
+public:
+  typedef T* pointer;
+  typedef T element_type;
+  typedef D deleter_type;
+
+  UniquePtr()
+    : m_ptr(pointer())
+  {
+  }
+
+  // Constructor with default deleter.
+  explicit UniquePtr(pointer ptr)
+    : m_ptr(ptr)
+  {
+  }
+
+  // Constructor with customized deleter.
+  UniquePtr(pointer ptr, deleter_type deleter)
+    : m_ptr(ptr)
+    , m_deleter(deleter)
+  {
+  }
+
+  // Releases one reference from the pointee.
+  ~UniquePtr()
+  {
+    if (m_ptr)
+      m_deleter(m_ptr);
+  }
+
+  void reset(pointer ptr = pointer())
+  {
+    if (m_ptr)
+      m_deleter(m_ptr);
+    m_ptr = ptr;
+  }
+
+  pointer release()
+  {
+    pointer ptr(m_ptr);
+    m_ptr = pointer();
+    return ptr;
+  }
+
+  pointer get() const { return m_ptr; }
+  element_type& operator*() const { return *m_ptr; }
+  pointer operator->() const { return m_ptr; }
+  operator pointer() const { return m_ptr; }
+
+private:
+  pointer m_ptr;			 // The pointee object.
+  deleter_type m_deleter;		 // The deleter.
+
+  DISABLE_COPYING(UniquePtr);
+};
+
+#endif
diff --git a/src/base/unique_ptr_unittest.cpp b/src/base/unique_ptr_unittest.cpp
new file mode 100644
index 000000000..25fa348a7
--- /dev/null
+++ b/src/base/unique_ptr_unittest.cpp
@@ -0,0 +1,91 @@
+// ASE base library
+// Copyright (C) 2001-2011  David Capello
+//
+// This source file is ditributed under a BSD-like license, please
+// read LICENSE.txt for more information.
+
+#include <gtest/gtest.h>
+
+#include "base/unique_ptr.h"
+
+TEST(UniquePtr, DefaultCtor)
+{
+  UniquePtr<int> a;
+  EXPECT_TRUE(NULL == a.get());
+
+  a.reset(new int(2));
+  ASSERT_TRUE(NULL != a.get());
+  EXPECT_TRUE(2 == *a);
+
+  a.reset();
+  EXPECT_TRUE(NULL == a.get());
+}
+
+TEST(UniquePtr, IntPtr)
+{
+  UniquePtr<int> a(new int(5));
+  EXPECT_EQ(5, *a);
+}
+
+TEST(UniquePtr, CopyValues)
+{
+  UniquePtr<int> a(new int(3));
+  UniquePtr<int> b(new int(4));
+
+  EXPECT_EQ(3, *a);
+  EXPECT_EQ(4, *b);
+
+  *a = *b;
+
+  EXPECT_EQ(4, *a);
+  EXPECT_EQ(4, *b);
+}
+
+int valueInDtor;
+
+class A
+{
+  int m_value;
+public:
+  A(int value) : m_value(value) { }
+  ~A() { valueInDtor = m_value; }
+};
+
+TEST(UniquePtr, PtrToStruct)
+{
+  valueInDtor = 0;
+  {
+    UniquePtr<A> a(new A(100));
+    {
+      UniquePtr<A> b(new A(200));
+      {
+	UniquePtr<A> c(new A(300));
+
+	EXPECT_EQ(0, valueInDtor);
+
+	c.reset();
+	EXPECT_EQ(300, valueInDtor);
+
+	c.reset(new A(400));
+      }
+      EXPECT_EQ(400, valueInDtor);
+    }
+    EXPECT_EQ(200, valueInDtor);
+  }
+  EXPECT_EQ(100, valueInDtor);
+}
+
+TEST(UniquePtr, Release)
+{
+  UniquePtr<int> a(new int(5));
+  EXPECT_EQ(5, *a);
+
+  int* ptr = a.release();
+  delete ptr;
+}
+
+int main(int argc, char** argv)
+{
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}