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diff --git a/cpukit/include/rtems/score/heap.h b/cpukit/include/rtems/score/heap.h
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+/**
+ * @file
+ *
+ * @ingroup ScoreHeap
+ *
+ * @brief Heap Handler API
+ */
+
+/*
+ *  COPYRIGHT (c) 1989-2006.
+ *  On-Line Applications Research Corporation (OAR).
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.org/license/LICENSE.
+ */
+
+#ifndef _RTEMS_SCORE_HEAP_H
+#define _RTEMS_SCORE_HEAP_H
+
+#include <rtems/score/cpu.h>
+#include <rtems/score/thread.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef RTEMS_DEBUG
+  #define HEAP_PROTECTION
+#endif
+
+/**
+ * @defgroup ScoreHeap Heap Handler
+ *
+ * @ingroup Score
+ *
+ * @brief The Heap Handler provides a heap.
+ *
+ * A heap is a doubly linked list of variable size blocks which are allocated
+ * using the first fit method.  Garbage collection is performed each time a
+ * block is returned to the heap by coalescing neighbor blocks.  Control
+ * information for both allocated and free blocks is contained in the heap
+ * area.  A heap control structure contains control information for the heap.
+ *
+ * The alignment routines could be made faster should we require only powers of
+ * two to be supported for page size, alignment and boundary arguments.  The
+ * minimum alignment requirement for pages is currently CPU_ALIGNMENT and this
+ * value is only required to be multiple of two and explicitly not required to
+ * be a power of two.
+ *
+ * There are two kinds of blocks.  One sort describes a free block from which
+ * we can allocate memory.  The other blocks are used and provide an allocated
+ * memory area.  The free blocks are accessible via a list of free blocks.
+ *
+ * Blocks or areas cover a continuous set of memory addresses. They have a
+ * begin and end address.  The end address is not part of the set.  The size of
+ * a block or area equals the distance between the begin and end address in
+ * units of bytes.
+ *
+ * Free blocks look like:
+ * <table>
+ *   <tr>
+ *     <td rowspan=4>@ref Heap_Block</td><td>previous block size in case the
+ *       previous block is free, <br> otherwise it may contain data used by
+ *       the previous block</td>
+ *   </tr>
+ *   <tr>
+ *     <td>block size and a flag which indicates if the previous block is free
+ *       or used, <br> this field contains always valid data regardless of the
+ *       block usage</td>
+ *   </tr>
+ *   <tr><td>pointer to next block (this field is page size aligned)</td></tr>
+ *   <tr><td>pointer to previous block</td></tr>
+ *   <tr><td colspan=2>free space</td></tr>
+ * </table>
+ *
+ * Used blocks look like:
+ * <table>
+ *   <tr>
+ *     <td rowspan=4>@ref Heap_Block</td><td>previous block size in case the
+ *       previous block is free,<br>otherwise it may contain data used by
+ *       the previous block</td>
+ *   </tr>
+ *   <tr>
+ *     <td>block size and a flag which indicates if the previous block is free
+ *       or used, <br> this field contains always valid data regardless of the
+ *       block usage</td>
+ *   </tr>
+ *   <tr><td>begin of allocated area (this field is page size aligned)</td></tr>
+ *   <tr><td>allocated space</td></tr>
+ *   <tr><td colspan=2>allocated space</td></tr>
+ * </table>
+ *
+ * The heap area after initialization contains two blocks and looks like:
+ * <table>
+ *   <tr><th>Label</th><th colspan=2>Content</th></tr>
+ *   <tr><td>heap->area_begin</td><td colspan=2>heap area begin address</td></tr>
+ *   <tr>
+ *     <td>first_block->prev_size</td>
+ *     <td colspan=2>
+ *       subordinate heap area end address (this will be used to maintain a
+ *       linked list of scattered heap areas)
+ *     </td>
+ *   </tr>
+ *   <tr>
+ *     <td>first_block->size</td>
+ *     <td colspan=2>size available for allocation
+ *       | @c HEAP_PREV_BLOCK_USED</td>
+ *   </tr>
+ *   <tr>
+ *     <td>first_block->next</td><td>_Heap_Free_list_tail(heap)</td>
+ *     <td rowspan=3>memory area available for allocation</td>
+ *   </tr>
+ *   <tr><td>first_block->prev</td><td>_Heap_Free_list_head(heap)</td></tr>
+ *   <tr><td>...</td></tr>
+ *   <tr>
+ *     <td>last_block->prev_size</td><td colspan=2>size of first block</td>
+ *   </tr>
+ *   <tr>
+ *     <td>last_block->size</td>
+ *     <td colspan=2>first block begin address - last block begin address</td>
+ *   </tr>
+ *   <tr><td>heap->area_end</td><td colspan=2>heap area end address</td></tr>
+ * </table>
+ * The next block of the last block is the first block.  Since the first
+ * block indicates that the previous block is used, this ensures that the
+ * last block appears as used for the _Heap_Is_used() and _Heap_Is_free()
+ * functions.
+ */
+/**@{**/
+
+typedef struct Heap_Control Heap_Control;
+
+typedef struct Heap_Block Heap_Block;
+
+#ifndef HEAP_PROTECTION
+  #define HEAP_PROTECTION_HEADER_SIZE 0
+#else
+  #define HEAP_PROTECTOR_COUNT 2
+
+  #define HEAP_BEGIN_PROTECTOR_0 ((uintptr_t) 0xfd75a98f)
+  #define HEAP_BEGIN_PROTECTOR_1 ((uintptr_t) 0xbfa1f177)
+  #define HEAP_END_PROTECTOR_0 ((uintptr_t) 0xd6b8855e)
+  #define HEAP_END_PROTECTOR_1 ((uintptr_t) 0x13a44a5b)
+
+  #define HEAP_FREE_PATTERN ((uintptr_t) 0xe7093cdf)
+
+  #define HEAP_PROTECTION_OBOLUS ((Heap_Block *) 1)
+
+  typedef void (*_Heap_Protection_handler)(
+     Heap_Control *heap,
+     Heap_Block *block
+  );
+
+  typedef struct {
+    _Heap_Protection_handler block_initialize;
+    _Heap_Protection_handler block_check;
+    _Heap_Protection_handler block_error;
+    void *handler_data;
+    Heap_Block *first_delayed_free_block;
+    Heap_Block *last_delayed_free_block;
+    uintptr_t delayed_free_block_count;
+    uintptr_t delayed_free_fraction;
+  } Heap_Protection;
+
+  typedef struct {
+    uintptr_t protector [HEAP_PROTECTOR_COUNT];
+    Heap_Block *next_delayed_free_block;
+    Thread_Control *task;
+    void *tag;
+  } Heap_Protection_block_begin;
+
+  typedef struct {
+    uintptr_t protector [HEAP_PROTECTOR_COUNT];
+  } Heap_Protection_block_end;
+
+  #define HEAP_PROTECTION_HEADER_SIZE \
+    (sizeof(Heap_Protection_block_begin) + sizeof(Heap_Protection_block_end))
+#endif
+
+/**
+ * @brief The block header consists of the two size fields
+ * (@ref Heap_Block.prev_size and @ref Heap_Block.size_and_flag).
+ */
+#define HEAP_BLOCK_HEADER_SIZE \
+  (2 * sizeof(uintptr_t) + HEAP_PROTECTION_HEADER_SIZE)
+
+/**
+ * @brief Description for free or used blocks.
+ */
+struct Heap_Block {
+  /**
+   * @brief Size of the previous block or part of the allocated area of the
+   * previous block.
+   *
+   * This field is only valid if the previous block is free.  This case is
+   * indicated by a cleared @c HEAP_PREV_BLOCK_USED flag in the
+   * @a size_and_flag field of the current block.
+   *
+   * In a used block only the @a size_and_flag field needs to be valid.  The
+   * @a prev_size field of the current block is maintained by the previous
+   * block.  The current block can use the @a prev_size field in the next block
+   * for allocation.
+   */
+  uintptr_t prev_size;
+
+  #ifdef HEAP_PROTECTION
+    Heap_Protection_block_begin Protection_begin;
+  #endif
+
+  /**
+   * @brief Contains the size of the current block and a flag which indicates
+   * if the previous block is free or used.
+   *
+   * If the flag @c HEAP_PREV_BLOCK_USED is set, then the previous block is
+   * used, otherwise the previous block is free.  A used previous block may
+   * claim the @a prev_size field for allocation.  This trick allows to
+   * decrease the overhead in the used blocks by the size of the @a prev_size
+   * field.  As sizes are required to be multiples of two, the least
+   * significant bits would be always zero. We use this bit to store the flag.
+   *
+   * This field is always valid.
+   */
+  uintptr_t size_and_flag;
+
+  #ifdef HEAP_PROTECTION
+    Heap_Protection_block_end Protection_end;
+  #endif
+
+  /**
+   * @brief Pointer to the next free block or part of the allocated area.
+   *
+   * This field is page size aligned and begins of the allocated area in case
+   * the block is used.
+   *
+   * This field is only valid if the block is free and thus part of the free
+   * block list.
+   */
+  Heap_Block *next;
+
+  /**
+   * @brief Pointer to the previous free block or part of the allocated area.
+   *
+   * This field is only valid if the block is free and thus part of the free
+   * block list.
+   */
+  Heap_Block *prev;
+};
+
+/**
+ * @brief Run-time heap statistics.
+ *
+ * The value @a searches / @a allocs gives the mean number of searches per
+ * allocation, while @a max_search gives maximum number of searches ever
+ * performed on a single allocation call.
+ */
+typedef struct {
+  /**
+   * @brief Lifetime number of bytes allocated from this heap.
+   *
+   * This value is an integral multiple of the page size.
+   */
+  uint64_t lifetime_allocated;
+
+  /**
+   * @brief Lifetime number of bytes freed to this heap.
+   *
+   * This value is an integral multiple of the page size.
+   */
+  uint64_t lifetime_freed;
+
+  /**
+   * @brief Size of the allocatable area in bytes.
+   *
+   * This value is an integral multiple of the page size.
+   */
+  uintptr_t size;
+
+  /**
+   * @brief Current free size in bytes.
+   *
+   * This value is an integral multiple of the page size.
+   */
+  uintptr_t free_size;
+
+  /**
+   * @brief Minimum free size ever in bytes.
+   *
+   * This value is an integral multiple of the page size.
+   */
+  uintptr_t min_free_size;
+
+  /**
+   * @brief Current number of free blocks.
+   */
+  uint32_t free_blocks;
+
+  /**
+   * @brief Maximum number of free blocks ever.
+   */
+  uint32_t max_free_blocks;
+
+  /**
+   * @brief Current number of used blocks.
+   */
+  uint32_t used_blocks;
+
+  /**
+   * @brief Maximum number of blocks searched ever.
+   */
+  uint32_t max_search;
+
+  /**
+   * @brief Total number of searches.
+   */
+  uint32_t searches;
+
+  /**
+   * @brief Total number of successful allocations.
+   */
+  uint32_t allocs;
+
+  /**
+   * @brief Total number of failed allocations.
+   */
+  uint32_t failed_allocs;
+
+  /**
+   * @brief Total number of successful frees.
+   */
+  uint32_t frees;
+
+  /**
+   * @brief Total number of successful resizes.
+   */
+  uint32_t resizes;
+} Heap_Statistics;
+
+/**
+ * @brief Control block used to manage a heap.
+ */
+struct Heap_Control {
+  Heap_Block free_list;
+  uintptr_t page_size;
+  uintptr_t min_block_size;
+  uintptr_t area_begin;
+  uintptr_t area_end;
+  Heap_Block *first_block;
+  Heap_Block *last_block;
+  Heap_Statistics stats;
+  #ifdef HEAP_PROTECTION
+    Heap_Protection Protection;
+  #endif
+};
+
+/**
+ * @brief Information about blocks.
+ */
+typedef struct {
+  /**
+   * @brief Number of blocks of this type.
+   */
+  uintptr_t number;
+
+  /**
+   * @brief Largest block of this type.
+   */
+  uintptr_t largest;
+
+  /**
+   * @brief Total size of the blocks of this type.
+   */
+  uintptr_t total;
+} Heap_Information;
+
+/**
+ * @brief Information block returned by _Heap_Get_information().
+ */
+typedef struct {
+  Heap_Information Free;
+  Heap_Information Used;
+  Heap_Statistics Stats;
+} Heap_Information_block;
+
+/**
+ * @brief Heap area structure for table based heap initialization and
+ * extension.
+ *
+ * @see Heap_Initialization_or_extend_handler.
+ */
+typedef struct {
+  void *begin;
+  uintptr_t size;
+} Heap_Area;
+
+/**
+ * @brief Heap initialization and extend handler type.
+ *
+ * This helps to do a table based heap initialization and extension.  Create a
+ * table of Heap_Area elements and iterate through it.  Set the handler to
+ * _Heap_Initialize() in the first iteration and then to _Heap_Extend().
+ *
+ * @see Heap_Area, _Heap_Initialize(), _Heap_Extend(), or _Heap_No_extend().
+ */
+typedef uintptr_t (*Heap_Initialization_or_extend_handler)(
+  Heap_Control *heap,
+  void *area_begin,
+  uintptr_t area_size,
+  uintptr_t page_size_or_unused
+);
+
+/**
+ * @brief Extends the memory available for the heap @a heap using the memory
+ * area starting at @a area_begin of size @a area_size bytes.
+ *
+ * There are no alignment requirements for the memory area.  The memory area
+ * must be big enough to contain some maintenance blocks.  It must not overlap
+ * parts of the current heap memory areas.  Disconnected memory areas added to
+ * the heap will lead to used blocks which cover the gaps.  Extending with an
+ * inappropriate memory area will corrupt the heap resulting in undefined
+ * behaviour.
+ *
+ * The unused fourth parameter is provided to have the same signature as
+ * _Heap_Initialize().
+ *
+ * Returns the extended space available for allocation, or zero in case of failure.
+ *
+ * @see Heap_Initialization_or_extend_handler.
+ */
+uintptr_t _Heap_Extend(
+  Heap_Control *heap,
+  void *area_begin,
+  uintptr_t area_size,
+  uintptr_t unused
+);
+
+/**
+ * @brief This function returns always zero.
+ *
+ * This function only returns zero and does nothing else.
+ *
+ * Returns always zero.
+ *
+ * @see Heap_Initialization_or_extend_handler.
+ */
+uintptr_t _Heap_No_extend(
+  Heap_Control *unused_0,
+  void *unused_1,
+  uintptr_t unused_2,
+  uintptr_t unused_3
+);
+
+RTEMS_INLINE_ROUTINE uintptr_t _Heap_Align_up(
+  uintptr_t value,
+  uintptr_t alignment
+)
+{
+  uintptr_t remainder = value % alignment;
+
+  if ( remainder != 0 ) {
+    return value - remainder + alignment;
+  } else {
+    return value;
+  }
+}
+
+RTEMS_INLINE_ROUTINE uintptr_t _Heap_Min_block_size( uintptr_t page_size )
+{
+  return _Heap_Align_up( sizeof( Heap_Block ), page_size );
+}
+
+/**
+ * @brief Returns the worst case overhead to manage a memory area.
+ */
+RTEMS_INLINE_ROUTINE uintptr_t _Heap_Area_overhead(
+  uintptr_t page_size
+)
+{
+  if ( page_size != 0 ) {
+    page_size = _Heap_Align_up( page_size, CPU_ALIGNMENT );
+  } else {
+    page_size = CPU_ALIGNMENT;
+  }
+
+  return 2 * (page_size - 1) + HEAP_BLOCK_HEADER_SIZE;
+}
+
+/**
+ * @brief Returns the size with administration and alignment overhead for one
+ * allocation.
+ */
+RTEMS_INLINE_ROUTINE uintptr_t _Heap_Size_with_overhead(
+  uintptr_t page_size,
+  uintptr_t size,
+  uintptr_t alignment
+)
+{
+  if ( page_size != 0 ) {
+    page_size = _Heap_Align_up( page_size, CPU_ALIGNMENT );
+  } else {
+    page_size = CPU_ALIGNMENT;
+  }
+
+  if ( page_size < alignment ) {
+    page_size = alignment;
+  }
+
+  return HEAP_BLOCK_HEADER_SIZE + page_size - 1 + size;
+}
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+/* end of include file */