/* xmalloc.c -- malloc with out of memory checking
  Copyright (C) 1990-1996, 2000-2003, 2005-2006 Free Software Foundation, Inc.

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2, or (at your option)
  any later version.

  This program 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 General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software Foundation,
  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

#include <config.h>

/* Specification.  */
#include "xalloc.h"

#include <stdlib.h>

#include "error.h"
#include "exit.h"
#include "gettext.h"

#define _(str) gettext (str)


/* Exit value when the requested amount of memory is not available.
  The caller may set it to some other value.  */
int xmalloc_exit_failure = EXIT_FAILURE;

void
xalloc_die ()
{
 error (xmalloc_exit_failure, 0, _("memory exhausted"));
 /* The `noreturn' cannot be given to error, since it may return if
    its first argument is 0.  To help compilers understand the
    xalloc_die does terminate, call exit. */
 exit (EXIT_FAILURE);
}

static void *
fixup_null_alloc (size_t n)
{
 void *p;

 p = 0;
 if (n == 0)
   p = malloc ((size_t) 1);
 if (p == NULL)
   xalloc_die ();
 return p;
}

/* Allocate N bytes of memory dynamically, with error checking.  */

void *
xmalloc (size_t n)
{
 void *p;

 p = malloc (n);
 if (p == NULL)
   p = fixup_null_alloc (n);
 return p;
}

/* Allocate SIZE bytes of memory dynamically, with error checking,
  and zero it.  */

void *
xzalloc (size_t size)
{
 void *p;

 p = xmalloc (size);
 memset (p, 0, size);
 return p;
}

/* Allocate memory for N elements of S bytes, with error checking,
  and zero it.  */

void *
xcalloc (size_t n, size_t s)
{
 void *p;

 p = calloc (n, s);
 if (p == NULL)
   p = fixup_null_alloc (n);
 return p;
}

/* Change the size of an allocated block of memory P to N bytes,
  with error checking.
  If P is NULL, run xmalloc.  */

void *
xrealloc (void *p, size_t n)
{
 if (p == NULL)
   return xmalloc (n);
 p = realloc (p, n);
 if (p == NULL)
   p = fixup_null_alloc (n);
 return p;
}