Subversion Repositories or1k

/*

 * libc/stdlib/malloc/heap_alloc.c -- allocate memory from a heap

 *

 *  Copyright (C) 2002  NEC Corporation

 *  Copyright (C) 2002  Miles Bader <miles@gnu.org>

 *

 * This file is subject to the terms and conditions of the GNU Lesser

 * General Public License.  See the file COPYING.LIB in the main

 * directory of this archive for more details.

 *

 * Written by Miles Bader <miles@gnu.org>

 */

#include <stdlib.h>

#include "heap.h"

/* Allocate and return a block at least *SIZE bytes long from HEAP.

   *SIZE is adjusted to reflect the actual amount allocated (which may be

   greater than requested).  */

void *

__heap_alloc (struct heap *heap, size_t *size)

{

  struct heap_free_area *fa;

  size_t _size = *size;

  void *mem = 0;

  _size = HEAP_ADJUST_SIZE (_size);

  if (_size < sizeof (struct heap_free_area))

    /* Because we sometimes must use a freed block to hold a free-area node,

       we must make sure that every allocated block can hold one.  */

    _size = HEAP_ADJUST_SIZE (sizeof (struct heap_free_area));

  HEAP_DEBUG (heap, "before __heap_alloc");

  /* Look for a free area that can contain _SIZE bytes.  */

  for (fa = heap->free_areas; fa; fa = fa->next)

    if (fa->size >= _size)

      {

        /* Found one!  */

        mem = HEAP_FREE_AREA_START (fa);

        *size = __heap_free_area_alloc (heap, fa, _size);

        break;

      }

  HEAP_DEBUG (heap, "after __heap_alloc");

  return mem;

}