From af3288263359cdce86f3d0c753961eee9560e4cf Mon Sep 17 00:00:00 2001
From: Felix Morgner <felix.morgner@ost.ch>
Date: Thu, 23 Jul 2026 00:11:27 +0200
Subject: kstd: add shared_ptr aliasing constructor

---
 libs/kstd/kstd/bits/shared_ptr.hpp | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

(limited to 'libs/kstd')

diff --git a/libs/kstd/kstd/bits/shared_ptr.hpp b/libs/kstd/kstd/bits/shared_ptr.hpp
index 7af0a00e..8d5dc1a8 100644
--- a/libs/kstd/kstd/bits/shared_ptr.hpp
+++ b/libs/kstd/kstd/bits/shared_ptr.hpp
@@ -360,7 +360,7 @@ namespace kstd
     }
 
     /**
-     * @brief Constructor a shared_ptr from a weak_ptr. If other is not expired, constructs a shared_ptr which shares
+     * @brief Construct a shared_ptr from a weak_ptr. If other is not expired, constructs a shared_ptr which shares
      * ownership of the object managed by other. Otherwise, constructs an empty shared_ptr.
      *
      * @param other The weak_ptr to construct from.
@@ -386,6 +386,23 @@ namespace kstd
       }
     }
 
+    //! Aliasing constructor.
+    //!
+    //! @tparam U The type of the object managed by other.
+    //! @param other The shared_ptr to share ownership with.
+    //! @param pointer The pointer this shared_ptr should own.
+    template<typename Y>
+      requires bits::is_shared_pointer_ctor_compatible<Y *, T *>::value
+    shared_ptr(shared_ptr<Y> const & other, T * pointer) noexcept
+        : m_storage{pointer}
+        , m_control_block{other.m_control_block}
+    {
+      if (m_control_block != nullptr)
+      {
+        ++(m_control_block->strong_count);
+      }
+    }
+
     /**
      * @brief Copy constructor.
      *
@@ -734,6 +751,12 @@ namespace kstd
     return shared_ptr<T>(new T(std::forward<Args>(args)...));
   }
 
+  template<typename T, typename U>
+  [[nodiscard]] auto static_pointer_cast(shared_ptr<U> const & other) noexcept -> shared_ptr<T>
+  {
+    return shared_ptr<T>{other, static_cast<T *>(other.get())};
+  }
+
   /**
    * @brief Equality operator for shared_ptr. Two shared_ptr instances are equal if they point to the same object
    * @tparam T, U Types of the managed objects of the shared_ptr instances being compared.
-- 
cgit v1.2.3