1 /* xmalloc.c -- malloc with out of memory checking
3 Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
4 1999, 2000, 2002, 2003, 2004, 2005, 2006 Free Software Foundation,
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software Foundation,
19 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
29 # define SIZE_MAX ((size_t) -1)
32 /* 1 if calloc is known to be compatible with GNU calloc. This
33 matters if we are not also using the calloc module, which defines
34 HAVE_CALLOC and supports the GNU API even on non-GNU platforms. */
35 #if defined HAVE_CALLOC || defined __GLIBC__
36 enum { HAVE_GNU_CALLOC = 1 };
38 enum { HAVE_GNU_CALLOC = 0 };
41 /* Allocate N bytes of memory dynamically, with error checking. */
52 /* Change the size of an allocated block of memory P to N bytes,
53 with error checking. */
56 xrealloc (void *p, size_t n)
64 /* If P is null, allocate a block of at least *PN bytes; otherwise,
65 reallocate P so that it contains more than *PN bytes. *PN must be
66 nonzero unless P is null. Set *PN to the new block's size, and
67 return the pointer to the new block. *PN is never set to zero, and
68 the returned pointer is never null. */
71 x2realloc (void *p, size_t *pn)
73 return x2nrealloc (p, pn, 1);
76 /* Allocate S bytes of zeroed memory dynamically, with error checking.
77 There's no need for xnzalloc (N, S), since it would be equivalent
83 return memset (xmalloc (s), 0, s);
86 /* Allocate zeroed memory for N elements of S bytes, with error
87 checking. S must be nonzero. */
90 xcalloc (size_t n, size_t s)
93 /* Test for overflow, since some calloc implementations don't have
94 proper overflow checks. But omit overflow and size-zero tests if
95 HAVE_GNU_CALLOC, since GNU calloc catches overflow and never
96 returns NULL if successful. */
97 if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s))
98 || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
103 /* Clone an object P of size S, with error checking. There's no need
104 for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any
105 need for an arithmetic overflow check. */
108 xmemdup (void const *p, size_t s)
110 return memcpy (xmalloc (s), p, s);
116 xstrdup (char const *string)
118 return xmemdup (string, strlen (string) + 1);