Merge branch 'pull-request/#924-Add-an-etl--nullptr_t-type-to-etl-nul…

…lptr.h' into development
ETLCPP · Jul 20, 2024 · 5885433 · 5885433
2 parents 2e30aa6 + e71596a
commit 5885433
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Showing 3 changed files with 50 additions and 45 deletions.
diff --git a/include/etl/memory.h b/include/etl/memory.h
@@ -1395,14 +1395,15 @@ namespace etl
  //*********************************
  void reset(pointer p_ = pointer()) ETL_NOEXCEPT
  {
- assert(p_ != p);
-
- pointer value = p;
- p = p_;
-
- if (value != ETL_NULLPTR)
+ if (p_ == ETL_NULLPTR || p_ != p)
  {
- deleter(value);
+ pointer value = p;
+ p = p_;
+
+ if (value != ETL_NULLPTR)
+ {
+ deleter(value);
+ }
  }
  }
 
@@ -1420,29 +1421,16 @@ namespace etl
  return (p != ETL_NULLPTR);
  }
 
-#if ETL_USING_STL && ETL_USING_CPP11
  //*********************************
- unique_ptr& operator =(std::nullptr_t) ETL_NOEXCEPT
+ unique_ptr& operator =(etl::nullptr_t) ETL_NOEXCEPT
  {
  if (p)
  {
- reset(nullptr);
+ reset(ETL_NULLPTR);
  }
 
  return *this;
  }
-#else
- //*********************************
- unique_ptr& operator =(void*) ETL_NOEXCEPT
- {
- if (p)
- {
- reset(NULL);
- }
-
- return *this;
- }
-#endif
 
 #if ETL_USING_CPP11
  //*********************************
@@ -1605,23 +1593,29 @@ namespace etl
  {
  pointer value = p;
  p = ETL_NULLPTR;
- return value;
+ return value; 
  }
 
  //*********************************
  void reset(pointer p_) ETL_NOEXCEPT
  {
- assert(p_ != p);
-
- pointer value = p;
- p = p_;
-
- if (value != ETL_NULLPTR)
+ if (p_ != p)
  {
- deleter(value);
+ pointer value = p;
+ p = p_;
+
+ if (value != ETL_NULLPTR)
+ {
+ deleter(value);
+ }
  }
  }
 
+ void reset(etl::nullptr_t = ETL_NULLPTR) ETL_NOEXCEPT
+ {
+ reset(pointer());
+ }
+
  //*********************************
  void swap(unique_ptr& v) ETL_NOEXCEPT
  {
@@ -1636,23 +1630,13 @@ namespace etl
  return (p != ETL_NULLPTR);
  }
 
-#if ETL_USING_STL && ETL_USING_CPP11
  //*********************************
- unique_ptr& operator =(std::nullptr_t) ETL_NOEXCEPT
+ unique_ptr& operator =(etl::nullptr_t) ETL_NOEXCEPT
  {
- reset(nullptr);
+ reset(ETL_NULLPTR);
 
  return *this;
  }
-#else
- //*********************************
- unique_ptr& operator =(void*) ETL_NOEXCEPT
- {
- reset(NULL);
-
- return *this;
- }
-#endif
 
 #if ETL_USING_CPP11
  //*********************************

diff --git a/include/etl/nullptr.h b/include/etl/nullptr.h
@@ -35,13 +35,33 @@ SOFTWARE.
 
 #include <stddef.h>
 
+namespace etl
+{
 #if ETL_CPP11_NOT_SUPPORTED
- // Use the old style C++ NULL definition.
- #define ETL_NULLPTR 0
+ class nullptr_t
+ {
+ public:
+ template <class T>
+ inline operator T*() const { return 0; }
+
+ template <class C, class T>
+ inline operator T C::* () const { return 0; }
+
+ inline bool operator==(nullptr_t) const { return true; }
+ inline bool operator!=(nullptr_t) const { return false; }
+ private:
+ void operator&() const ETL_DELETE; // cannot take the address of ETL_NULLPTR
+ };
+
+ static const nullptr_t _nullptr = nullptr_t();
+
+ #define ETL_NULLPTR (etl::_nullptr)
 #else
  // Use the new style nullptr.
+ typedef decltype(nullptr) nullptr_t;
  #define ETL_NULLPTR nullptr
 #endif
+}
 
 #endif
 
diff --git a/include/etl/private/addressof.h b/include/etl/private/addressof.h
@@ -32,6 +32,7 @@ SOFTWARE.
 #define ETL_ADDRESSOF_INCLUDED
 
 #include "../platform.h"
+#include "../type_traits.h"
 
 #if defined(ETL_IN_UNIT_TEST) || ETL_USING_STL
  #include <memory>
@@ -48,7 +49,7 @@ namespace etl
  ///\ingroup memory
  //*****************************************************************************
  template <typename T>
- ETL_CONSTEXPR17 T* addressof(T& t)
+ ETL_CONSTEXPR17 typename etl::enable_if<!etl::is_same<T, etl::nullptr_t>::value, T>::type* addressof(T& t)
  {
 #if ETL_USING_STL && ETL_USING_CPP11
  return std::addressof(t);