gnu/dist/texinfo/lib/xalloc.h

   1 /*      $NetBSD$        */
   2
   3 /* xalloc.h -- malloc with out-of-memory checking
   4
   5    Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   6    1999, 2000, 2003, 2004 Free Software Foundation, Inc.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2, or (at your option)
  11    any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software Foundation,
  20    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #ifndef XALLOC_H_
  23 # define XALLOC_H_
  24
  25 # include <stddef.h>
  26
  27
  28 # ifdef __cplusplus
  29 extern "C" {
  30 # endif
  31
  32
  33 # ifndef __attribute__
  34 #  if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
  35 #   define __attribute__(x)
  36 #  endif
  37 # endif
  38
  39 # ifndef ATTRIBUTE_NORETURN
  40 #  define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
  41 # endif
  42
  43 /* This function is always triggered when memory is exhausted.
  44    It must be defined by the application, either explicitly
  45    or by using gnulib's xalloc-die module.  This is the
  46    function to call when one wants the program to die because of a
  47    memory allocation failure.  */
  48 extern void xalloc_die (void) ATTRIBUTE_NORETURN;
  49
  50 void *xmalloc (size_t s);
  51 void *xnmalloc (size_t n, size_t s);
  52 void *xzalloc (size_t s);
  53 void *xcalloc (size_t n, size_t s);
  54 void *xrealloc (void *p, size_t s);
  55 void *xnrealloc (void *p, size_t n, size_t s);
  56 void *x2realloc (void *p, size_t *pn);
  57 void *x2nrealloc (void *p, size_t *pn, size_t s);
  58 void *xclone (void const *p, size_t s);
  59 char *xstrdup (const char *str);
  60
  61 /* Return 1 if an array of N objects, each of size S, cannot exist due
  62    to size arithmetic overflow.  S must be positive and N must be
  63    nonnegative.  This is a macro, not an inline function, so that it
  64    works correctly even when SIZE_MAX < N.
  65
  66    By gnulib convention, SIZE_MAX represents overflow in size
  67    calculations, so the conservative dividend to use here is
  68    SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
  69    However, malloc (SIZE_MAX) fails on all known hosts where
  70    sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
  71    exactly-SIZE_MAX allocations on such hosts; this avoids a test and
  72    branch when S is known to be 1.  */
  73 # define xalloc_oversized(n, s) \
  74     ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
  75
  76 /* These macros are deprecated; they will go away soon, and are retained
  77    temporarily only to ease conversion to the functions described above.  */
  78 # define CCLONE(p, n) xclone (p, (n) * sizeof *(p))
  79 # define CLONE(p) xclone (p, sizeof *(p))
  80 # define NEW(type, var) type *var = xmalloc (sizeof (type))
  81 # define XCALLOC(type, n) xcalloc (n, sizeof (type))
  82 # define XMALLOC(type, n) xnmalloc (n, sizeof (type))
  83 # define XREALLOC(p, type, n) xnrealloc (p, n, sizeof (type))
  84 # define XFREE(p) free (p)
  85
  86
  87 # ifdef __cplusplus
  88 }
  89 # endif
  90
  91
  92 #endif /* !XALLOC_H_ */