1 /* xalloc.h -- malloc with out-of-memory checking 2 3 Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 4 1999, 2000, 2003, 2004 Free Software Foundation, Inc. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software Foundation, 18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ 19 20 #ifndef XALLOC_H_ 21 # define XALLOC_H_ 22 23 # include <stddef.h> 24 25 26 # ifdef __cplusplus 27 extern "C" { 28 # endif 29 30 31 # ifndef __attribute__ 32 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__ 33 # define __attribute__(x) 34 # endif 35 # endif 36 37 # ifndef ATTRIBUTE_NORETURN 38 # define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__)) 39 # endif 40 41 /* This function is always triggered when memory is exhausted. 42 It must be defined by the application, either explicitly 43 or by using gnulib's xalloc-die module. 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) ATTRIBUTE_NORETURN; 47 48 void *xmalloc (size_t s); 49 void *xnmalloc (size_t n, size_t s); 50 void *xzalloc (size_t s); 51 void *xcalloc (size_t n, size_t s); 52 void *xrealloc (void *p, size_t s); 53 void *xnrealloc (void *p, size_t n, size_t s); 54 void *x2realloc (void *p, size_t *pn); 55 void *x2nrealloc (void *p, size_t *pn, size_t s); 56 void *xmemdup (void const *p, size_t s); 57 char *xstrdup (char const *str); 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 # ifdef __cplusplus 75 } 76 # endif 77 78 79 #endif /* !XALLOC_H_ */ 80