From be278771eed11eaffe393c3454f6d7ba408a0041 Mon Sep 17 00:00:00 2001
From: Nick Holland <nick.holland@partner.samsung.com>
Date: Tue, 21 Feb 2017 15:59:47 +0000
Subject: [PATCH] Check memory being free'd from a memory pool, belongs to it.

Memory leak detected by Valgrind due to Scene Graph Layers
being deleted from a memory pool, even though they were heap
allocated.

Assert currently fires on shutting down dali-demo, and when
using text-editor.example

Leak fixed in
https://review.tizen.org/gerrit/#/c/115115/

Change-Id: I1254b56a3f3be17d662fb0622ebe407874df71cc
---
 dali/internal/common/fixed-size-memory-pool.cpp | 36 ++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/dali/internal/common/fixed-size-memory-pool.cpp b/dali/internal/common/fixed-size-memory-pool.cpp
index 63e3f4b..774d20c 100644
--- a/dali/internal/common/fixed-size-memory-pool.cpp
+++ b/dali/internal/common/fixed-size-memory-pool.cpp
@@ -42,7 +42,9 @@ struct FixedSizeMemoryPool::Impl
   {
     void* blockMemory;      ///< The allocated memory from which allocations can be made
     Block* nextBlock;       ///< The next block in the linked list
-
+#ifdef DEBUG_ENABLED
+    SizeType mBlockSize; ///< Size of the block in bytes
+#endif
     /**
      * @brief Construct a new block with given size
      *
@@ -50,6 +52,9 @@ struct FixedSizeMemoryPool::Impl
      */
     Block( SizeType size )
     : nextBlock( NULL )
+#ifdef DEBUG_ENABLED
+      ,mBlockSize( size )
+#endif
     {
       blockMemory = ::operator new( size );
       DALI_ASSERT_ALWAYS( blockMemory && "Out of memory" );
@@ -124,6 +129,31 @@ struct FixedSizeMemoryPool::Impl
 
     mCurrentBlockSize = 0;
   }
+#ifdef DEBUG_ENABLED
+
+  /**
+   * @brief check the memory being free'd exists inside the memory pool
+   * @param[in] memory address of object to remove
+   */
+  void CheckMemoryIsInsidePool( const void* const memory )
+  {
+    bool inRange = false;
+    const Block* block = &mMemoryBlocks;
+
+    while( block )
+    {
+      const void* const endOfBlock = reinterpret_cast<char *>( block->blockMemory )+ block->mBlockSize;
+
+      if( ( memory >= block->blockMemory ) && ( memory < (endOfBlock) ) )
+      {
+        inRange = true;
+        break;
+      }
+      block = block->nextBlock;
+    }
+    DALI_ASSERT_DEBUG( inRange && "Freeing memory that does not exist in memory pool" );
+  }
+#endif
 
   Mutex mMutex;                       ///< Mutex for thread-safe allocation and deallocation
 
@@ -175,6 +205,10 @@ void* FixedSizeMemoryPool::Allocate()
 
 void FixedSizeMemoryPool::Free( void* memory )
 {
+#ifdef DEBUG_ENABLED
+  mImpl->CheckMemoryIsInsidePool( memory );
+#endif
+
   // Add memory to head of deleted objects list. Store next address in the same memory space as the old object.
   *( reinterpret_cast< void** >( memory ) ) = mImpl->mDeletedObjects;
   mImpl->mDeletedObjects = memory;
-- 
2.7.4