memory.c

/* Memory allocation routines.

Copyright 1991, 1993, 1994, 2000, 2001, 2002 Free Software Foundation, Inc.

This file is part of the GNU MP Library.

The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your
option) any later version.

The GNU MP Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */

#include <stdio.h>
#include <stdlib.h> /* for malloc, realloc, free */

#include "gmp.h"
#include "gmp-impl.h"


void *	(*__gmp_allocate_func) __GMP_PROTO ((size_t)) = __gmp_default_allocate;
void *	(*__gmp_reallocate_func) __GMP_PROTO ((void *, size_t, size_t))
     = __gmp_default_reallocate;
void	(*__gmp_free_func) __GMP_PROTO ((void *, size_t)) = __gmp_default_free;


/* Default allocation functions.  In case of failure to allocate/reallocate
   an error message is written to stderr and the program aborts.  */

void *
__gmp_default_allocate (size_t size)
{
  void *ret;
#ifdef DEBUG
  size_t req_size = size;
  size += 2 * BYTES_PER_MP_LIMB;
#endif
  ret = malloc (size);
  if (ret == 0)
    {
      fprintf (stderr, "GNU MP: Cannot allocate memory (size=%lu)\n", (long) size);
      abort ();
    }

#ifdef DEBUG
  {
    mp_ptr p = ret;
    p++;
    p[-1] = (0xdeadbeef << 31) + 0xdeafdeed;
    if (req_size % BYTES_PER_MP_LIMB == 0)
      p[req_size / BYTES_PER_MP_LIMB] = ~((0xdeadbeef << 31) + 0xdeafdeed);
    ret = p;
  }
#endif
  return ret;
}

void *
__gmp_default_reallocate (void *oldptr, size_t old_size, size_t new_size)
{
  void *ret;

#ifdef DEBUG
  size_t req_size = new_size;

  if (old_size != 0)
    {
      mp_ptr p = oldptr;
      if (p[-1] != (0xdeadbeef << 31) + 0xdeafdeed)
	{
	  fprintf (stderr, "gmp: (realloc) data clobbered before allocation block\n");
	  abort ();
	}
      if (old_size % BYTES_PER_MP_LIMB == 0)
	if (p[old_size / BYTES_PER_MP_LIMB] != ~((0xdeadbeef << 31) + 0xdeafdeed))
	  {
	    fprintf (stderr, "gmp: (realloc) data clobbered after allocation block\n");
	    abort ();
	  }
      oldptr = p - 1;
    }

  new_size += 2 * BYTES_PER_MP_LIMB;
#endif

  ret = realloc (oldptr, new_size);
  if (ret == 0)
    {
      fprintf (stderr, "GNU MP: Cannot reallocate memory (old_size=%lu new_size=%lu)\n", (long) old_size, (long) new_size);
      abort ();
    }

#ifdef DEBUG
  {
    mp_ptr p = ret;
    p++;
    p[-1] = (0xdeadbeef << 31) + 0xdeafdeed;
    if (req_size % BYTES_PER_MP_LIMB == 0)
      p[req_size / BYTES_PER_MP_LIMB] = ~((0xdeadbeef << 31) + 0xdeafdeed);
    ret = p;
  }
#endif
  return ret;
}

void
__gmp_default_free (void *blk_ptr, size_t blk_size)
{
#ifdef DEBUG
  {
    mp_ptr p = blk_ptr;
    if (blk_size != 0)
      {
	if (p[-1] != (0xdeadbeef << 31) + 0xdeafdeed)
	  {
	    fprintf (stderr, "gmp: (free) data clobbered before allocation block\n");
	    abort ();
	  }
	if (blk_size % BYTES_PER_MP_LIMB == 0)
	  if (p[blk_size / BYTES_PER_MP_LIMB] != ~((0xdeadbeef << 31) + 0xdeafdeed))
	    {
	      fprintf (stderr, "gmp: (free) data clobbered after allocation block\n");
	      abort ();
	    }
      }
    blk_ptr = p - 1;
  }
#endif
  free (blk_ptr);
}