1  /* Memory allocation routines.
       2  
       3  Copyright 1991, 1993, 1994, 2000-2002, 2012 Free Software Foundation, Inc.
       4  
       5  This file is part of the GNU MP Library.
       6  
       7  The GNU MP Library is free software; you can redistribute it and/or modify
       8  it under the terms of either:
       9  
      10    * the GNU Lesser General Public License as published by the Free
      11      Software Foundation; either version 3 of the License, or (at your
      12      option) any later version.
      13  
      14  or
      15  
      16    * the GNU General Public License as published by the Free Software
      17      Foundation; either version 2 of the License, or (at your option) any
      18      later version.
      19  
      20  or both in parallel, as here.
      21  
      22  The GNU MP Library is distributed in the hope that it will be useful, but
      23  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
      24  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      25  for more details.
      26  
      27  You should have received copies of the GNU General Public License and the
      28  GNU Lesser General Public License along with the GNU MP Library.  If not,
      29  see https://www.gnu.org/licenses/.  */
      30  
      31  #include <stdio.h>
      32  #include <stdlib.h> /* for malloc, realloc, free */
      33  
      34  #include "gmp-impl.h"
      35  
      36  
      37  void * (*__gmp_allocate_func) (size_t) = __gmp_default_allocate;
      38  void * (*__gmp_reallocate_func) (void *, size_t, size_t) = __gmp_default_reallocate;
      39  void   (*__gmp_free_func) (void *, size_t) = __gmp_default_free;
      40  
      41  
      42  /* Default allocation functions.  In case of failure to allocate/reallocate
      43     an error message is written to stderr and the program aborts.  */
      44  
      45  void *
      46  __gmp_default_allocate (size_t size)
      47  {
      48    void *ret;
      49  #ifdef DEBUG
      50    size_t req_size = size;
      51    size += 2 * GMP_LIMB_BYTES;
      52  #endif
      53    ret = malloc (size);
      54    if (ret == 0)
      55      {
      56        fprintf (stderr, "GNU MP: Cannot allocate memory (size=%lu)\n", (long) size);
      57        abort ();
      58      }
      59  
      60  #ifdef DEBUG
      61    {
      62      mp_ptr p = ret;
      63      p++;
      64      p[-1] = (0xdeadbeef << 31) + 0xdeafdeed;
      65      if (req_size % GMP_LIMB_BYTES == 0)
      66        p[req_size / GMP_LIMB_BYTES] = ~((0xdeadbeef << 31) + 0xdeafdeed);
      67      ret = p;
      68    }
      69  #endif
      70    return ret;
      71  }
      72  
      73  void *
      74  __gmp_default_reallocate (void *oldptr, size_t old_size, size_t new_size)
      75  {
      76    void *ret;
      77  
      78  #ifdef DEBUG
      79    size_t req_size = new_size;
      80  
      81    if (old_size != 0)
      82      {
      83        mp_ptr p = oldptr;
      84        if (p[-1] != (0xdeadbeef << 31) + 0xdeafdeed)
      85  	{
      86  	  fprintf (stderr, "gmp: (realloc) data clobbered before allocation block\n");
      87  	  abort ();
      88  	}
      89        if (old_size % GMP_LIMB_BYTES == 0)
      90  	if (p[old_size / GMP_LIMB_BYTES] != ~((0xdeadbeef << 31) + 0xdeafdeed))
      91  	  {
      92  	    fprintf (stderr, "gmp: (realloc) data clobbered after allocation block\n");
      93  	    abort ();
      94  	  }
      95        oldptr = p - 1;
      96      }
      97  
      98    new_size += 2 * GMP_LIMB_BYTES;
      99  #endif
     100  
     101    ret = realloc (oldptr, new_size);
     102    if (ret == 0)
     103      {
     104        fprintf (stderr, "GNU MP: Cannot reallocate memory (old_size=%lu new_size=%lu)\n", (long) old_size, (long) new_size);
     105        abort ();
     106      }
     107  
     108  #ifdef DEBUG
     109    {
     110      mp_ptr p = ret;
     111      p++;
     112      p[-1] = (0xdeadbeef << 31) + 0xdeafdeed;
     113      if (req_size % GMP_LIMB_BYTES == 0)
     114        p[req_size / GMP_LIMB_BYTES] = ~((0xdeadbeef << 31) + 0xdeafdeed);
     115      ret = p;
     116    }
     117  #endif
     118    return ret;
     119  }
     120  
     121  void
     122  __gmp_default_free (void *blk_ptr, size_t blk_size)
     123  {
     124  #ifdef DEBUG
     125    {
     126      mp_ptr p = blk_ptr;
     127      if (blk_size != 0)
     128        {
     129  	if (p[-1] != (0xdeadbeef << 31) + 0xdeafdeed)
     130  	  {
     131  	    fprintf (stderr, "gmp: (free) data clobbered before allocation block\n");
     132  	    abort ();
     133  	  }
     134  	if (blk_size % GMP_LIMB_BYTES == 0)
     135  	  if (p[blk_size / GMP_LIMB_BYTES] != ~((0xdeadbeef << 31) + 0xdeafdeed))
     136  	    {
     137  	      fprintf (stderr, "gmp: (free) data clobbered after allocation block\n");
     138  	      abort ();
     139  	    }
     140        }
     141      blk_ptr = p - 1;
     142    }
     143  #endif
     144    free (blk_ptr);
     145  }