From 2bca7d5948e44df4bfbc469699e2d53fc7577492 Mon Sep 17 00:00:00 2001
From: Marika Lehmann <marika.lehmann@apex.ai>
Date: Thu, 1 Dec 2022 19:10:10 +0100
Subject: [PATCH] iox-#1732 Implement deallocate method

Signed-off-by: Marika Lehmann <marika.lehmann@apex.ai>
---
 .../iceoryx_hoofs/internal/cxx/storable_function.inl   |  1 -
 iceoryx_hoofs/memory/include/iox/bump_allocator.hpp    |  5 ++++-
 iceoryx_hoofs/memory/source/bump_allocator.cpp         | 10 ++++++++++
 .../test/moduletests/test_memory_bump_allocator.cpp    |  4 ++++
 4 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/iceoryx_hoofs/include/iceoryx_hoofs/internal/cxx/storable_function.inl b/iceoryx_hoofs/include/iceoryx_hoofs/internal/cxx/storable_function.inl
index bbb898e181a..d944c384fe5 100644
--- a/iceoryx_hoofs/include/iceoryx_hoofs/internal/cxx/storable_function.inl
+++ b/iceoryx_hoofs/include/iceoryx_hoofs/internal/cxx/storable_function.inl
@@ -173,7 +173,6 @@ void* allocate(byte_t* startAddress, uint64_t Capacity)
     uint64_t alignedPosition = cxx::align(reinterpret_cast<uint64_t>(startAddress), alignof(T));
     cxx::Expects(alignedPosition + sizeof(T) - reinterpret_cast<uint64_t>(startAddress) < Capacity
                  && "type does not fit into storage");
-    // cxx::Expects(alignedPosition + sizeof(T) < Capacity && "type does not fit into storage");
     return reinterpret_cast<void*>(alignedPosition);
 }
 
diff --git a/iceoryx_hoofs/memory/include/iox/bump_allocator.hpp b/iceoryx_hoofs/memory/include/iox/bump_allocator.hpp
index 0fe5a59fd83..dde3d30f95b 100644
--- a/iceoryx_hoofs/memory/include/iox/bump_allocator.hpp
+++ b/iceoryx_hoofs/memory/include/iox/bump_allocator.hpp
@@ -48,9 +48,12 @@ class BumpAllocator
     /// @note May terminate if out of memory or finalizeAllocation() was called before
     void* allocate(const uint64_t size, const uint64_t alignment) noexcept;
 
+    /// @brief mark the memory as unused
+    constexpr void deallocate() noexcept;
+
   protected:
     friend class posix::SharedMemoryObject;
-    // make free function; destructive move?
+    // make free function; destructive move? - then we would not be able to deallocate and allocate again afterwards
     void finalizeAllocation() noexcept;
 
   private:
diff --git a/iceoryx_hoofs/memory/source/bump_allocator.cpp b/iceoryx_hoofs/memory/source/bump_allocator.cpp
index 4e34f675b46..67608a35237 100644
--- a/iceoryx_hoofs/memory/source/bump_allocator.cpp
+++ b/iceoryx_hoofs/memory/source/bump_allocator.cpp
@@ -38,6 +38,8 @@ void* BumpAllocator::allocate(const uint64_t size, const uint64_t alignment) noe
     cxx::Expects(
         !m_allocationFinalized
         && "allocate() call after finalizeAllocation()! You are not allowed to acquire shared memory chunks anymore");
+    // return a nullptr instead of terminate? Then this could be checked in SharedMemoryObject and the log messages
+    // could be printed there...
 
     // NOLINTNEXTLINE(cppcoreguidelines-pro-type-reinterpret-cast) required for low level pointer alignment
     uint64_t currentAddress = reinterpret_cast<uint64_t>(m_startAddress) + m_currentPosition;
@@ -71,4 +73,12 @@ void BumpAllocator::finalizeAllocation() noexcept
     m_allocationFinalized = true;
 }
 
+constexpr void BumpAllocator::deallocate() noexcept
+{
+    m_startAddress = nullptr;
+    m_length = 0;
+    m_currentPosition = 0;
+    m_allocationFinalized = false;
+}
+
 } // namespace iox
diff --git a/iceoryx_hoofs/test/moduletests/test_memory_bump_allocator.cpp b/iceoryx_hoofs/test/moduletests/test_memory_bump_allocator.cpp
index bafa1c378de..e4f0dc640c6 100644
--- a/iceoryx_hoofs/test/moduletests/test_memory_bump_allocator.cpp
+++ b/iceoryx_hoofs/test/moduletests/test_memory_bump_allocator.cpp
@@ -153,4 +153,8 @@ TEST_F(BumpAllocator_Test, allocateAfterFinalizeAllocation)
     // NOLINTEND(hicpp-avoid-goto, cppcoreguidelines-avoid-goto, cert-err33-c, cppcoreguidelines-pro-type-vararg,
     // hiccpp-vararg)
 }
+
+// missing tests:
+// deallocate sets values to null
+// deallocate after finalizeAllocation works + allocation is possible again
 } // namespace