Clear old memory in contructor

4 files changed, 21 insertions, 28 deletions

diff --git a/arch/x86_64/include/arch/memory/heap/linked_list_allocator.hpp b/arch/x86_64/include/arch/memory/heap/linked_list_allocator.hpp
index 5ff13ca..03b8828 100644
--- a/arch/x86_64/include/arch/memory/heap/linked_list_allocator.hpp
+++ b/arch/x86_64/include/arch/memory/heap/linked_list_allocator.hpp
@@ -121,16 +121,6 @@ namespace teachos::arch::memory::heap
     auto coalesce_free_memory_block(memory_block * previous_block, memory_block * current_block, void * pointer,
                                     std::size_t size) -> void;
 
-    /**
-     * @brief Clears the memory of the previous memory block header.
-     *
-     * @note Done so the given pointer can be reused to construct other classes into, without having the old values.
-     * Required because we cannot call delete, because it causes "undefined reference to `sbrk`".
-     *
-     * @param pointer Address we want to clear the memory block header at (16 bytes).
-     */
-    auto clear_memory_block_header(void * pointer) -> void;
-
     std::size_t heap_start;  ///< Start of the allocatable heap area.
     std::size_t heap_end;    ///< End of the allocatable heap area.
     memory_block * first;    ///< First free entry in our memory.
diff --git a/arch/x86_64/include/arch/memory/heap/memory_block.hpp b/arch/x86_64/include/arch/memory/heap/memory_block.hpp
index c48d0cd..c62dd57 100644
--- a/arch/x86_64/include/arch/memory/heap/memory_block.hpp
+++ b/arch/x86_64/include/arch/memory/heap/memory_block.hpp
@@ -12,15 +12,24 @@ namespace teachos::arch::memory::heap
   struct memory_block
   {
     /**
-     * @brief Constructor,
+     * @brief Constructor. Clears all memory from the place it was allocated until the end (address +
+     * size).
      *
      * @param size Amount of free memory of this specific hole.
      * @param next Optional pointer to the next free memory.
      */
     memory_block(std::size_t size, memory_block * next);
 
-    std::size_t size;  ///< Amount of free memory this hole contains, has to always be atleast 16 bytes to hold the size
-                       ///< variable and the pointer to the next hole.
+    /**
+     * @brief Destructor. Clears all internal memory.
+     *
+     * @note Used so the memory can be reused to construct other classes into, without having the old values.
+     * Required because we cannot call delete, because it causes "undefined reference to `sbrk`".
+     */
+    ~memory_block();
+
+    std::size_t size;     ///< Amount of free memory this hole contains, has to always be atleast 16 bytes to hold the
+                          ///< size variable and the pointer to the next hole.
     memory_block * next;  ///< Optional pointer to the next free memory, holds nullptr if there is none.
   };
 }  // namespace teachos::arch::memory::heap
diff --git a/arch/x86_64/src/memory/heap/linked_list_allocator.cpp b/arch/x86_64/src/memory/heap/linked_list_allocator.cpp
index d0bf8e6..e5bae21 100644
--- a/arch/x86_64/src/memory/heap/linked_list_allocator.cpp
+++ b/arch/x86_64/src/memory/heap/linked_list_allocator.cpp
@@ -3,10 +3,6 @@
 #include "arch/exception_handling/assert.hpp"
 #include "arch/exception_handling/panic.hpp"
 
-#include <string.h>
-
-#include <algorithm>
-
 namespace teachos::arch::memory::heap
 {
   linked_list_allocator::linked_list_allocator(std::size_t heap_start, std::size_t heap_end)
@@ -112,7 +108,7 @@ namespace teachos::arch::memory::heap
     {
       previous_block->next = new_block;
     }
-    clear_memory_block_header(current_block);
+    current_block->~memory_block();
     return reinterpret_cast<void *>(start_address);
   }
 
@@ -134,8 +130,7 @@ namespace teachos::arch::memory::heap
     {
       block_size += current_block->size;
       next_block = current_block->next;
-
-      clear_memory_block_header(current_block);
+      current_block->~memory_block();
     }
 
     // If the block we want to deallocate is behind another free block and we can therefore combine both into one.
@@ -170,9 +165,4 @@ namespace teachos::arch::memory::heap
     previous_block->next = new_block;
   }
 
-  auto linked_list_allocator::clear_memory_block_header(void * pointer) -> void
-  {
-    memset(pointer, 0, min_allocatable_size());
-  }
-
 }  // namespace teachos::arch::memory::heap
diff --git a/arch/x86_64/src/memory/heap/memory_block.cpp b/arch/x86_64/src/memory/heap/memory_block.cpp
index b68dd6d..446cd96 100644
--- a/arch/x86_64/src/memory/heap/memory_block.cpp
+++ b/arch/x86_64/src/memory/heap/memory_block.cpp
@@ -1,11 +1,15 @@
 #include "arch/memory/heap/memory_block.hpp"
 
+#include <string.h>
+
 namespace teachos::arch::memory::heap
 {
   memory_block::memory_block(std::size_t size, memory_block * next)
-      : size(size)
-      , next(next)
   {
-    // Nothing to do
+    memset(static_cast<void *>(this), 0, size);
+    this->size = size;
+    this->next = next;
   }
+
+  memory_block::~memory_block() { memset(static_cast<void *>(this), 0, sizeof(memory_block)); }
 }  // namespace teachos::arch::memory::heap