gnu/dist/gettext/gettext-tools/lib/xalloc.h

   1 /* malloc with out of memory checking.
   2    Copyright (C) 2001-2004 Free Software Foundation, Inc.
   3    Written by Bruno Haible <haible@clisp.cons.org>, 2001.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software Foundation,
  17    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19 #ifndef _XALLOC_H
  20 #define _XALLOC_H
  21
  22 #include <stddef.h>
  23
  24
  25 #ifdef __cplusplus
  26 extern "C" {
  27 #endif
  28
  29
  30 /* Defined in xmalloc.c.  */
  31
  32 /* Allocate SIZE bytes of memory dynamically, with error checking.  */
  33 extern void *xmalloc (size_t size);
  34
  35 /* Allocate memory for NMEMB elements of SIZE bytes, with error checking.  */
  36 extern void *xcalloc (size_t nmemb, size_t size);
  37
  38 /* Change the size of an allocated block of memory PTR to SIZE bytes,
  39    with error checking.  If PTR is NULL, run xmalloc.  */
  40 extern void *xrealloc (void *ptr, size_t size);
  41
  42 /* This function is always triggered when memory is exhausted.  It is
  43    in charge of honoring the three previous items.  This is the
  44    function to call when one wants the program to die because of a
  45    memory allocation failure.  */
  46 extern void xalloc_die (void)
  47 #if (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 5)) && !__STRICT_ANSI__
  48      __attribute__ ((__noreturn__))
  49 #endif
  50      ;
  51
  52
  53 /* Defined in xstrdup.c.  */
  54
  55 /* Return a newly allocated copy of STRING.  */
  56 extern char *xstrdup (const char *string);
  57
  58
  59 /* Return 1 if an array of N objects, each of size S, cannot exist due
  60    to size arithmetic overflow.  S must be positive and N must be
  61    nonnegative.  This is a macro, not an inline function, so that it
  62    works correctly even when SIZE_MAX < N.
  63
  64    By gnulib convention, SIZE_MAX represents overflow in size
  65    calculations, so the conservative dividend to use here is
  66    SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
  67    However, malloc (SIZE_MAX) fails on all known hosts where
  68    sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
  69    exactly-SIZE_MAX allocations on such hosts; this avoids a test and
  70    branch when S is known to be 1.  */
  71 # define xalloc_oversized(n, s) \
  72     ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
  73
  74
  75 #ifdef __cplusplus
  76 }
  77 #endif
  78
  79
  80 #endif /* _XALLOC_H */