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, 2008 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 3 of the License, or
10 (at your option) any later version.
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, see <http://www.gnu.org/licenses/>. */
23 # define static_inline
32 # define SIZE_MAX ((size_t) -1)
35 /* 1 if calloc is known to be compatible with GNU calloc. This
36 matters if we are not also using the calloc module, which defines
37 HAVE_CALLOC and supports the GNU API even on non-GNU platforms. */
38 #if defined HAVE_CALLOC || defined __GLIBC__
39 enum { HAVE_GNU_CALLOC = 1 };
41 enum { HAVE_GNU_CALLOC = 0 };
44 /* Allocate N bytes of memory dynamically, with error checking. */
55 /* Change the size of an allocated block of memory P to N bytes,
56 with error checking. */
59 xrealloc (void *p, size_t n)
67 /* If P is null, allocate a block of at least *PN bytes; otherwise,
68 reallocate P so that it contains more than *PN bytes. *PN must be
69 nonzero unless P is null. Set *PN to the new block's size, and
70 return the pointer to the new block. *PN is never set to zero, and
71 the returned pointer is never null. */
74 x2realloc (void *p, size_t *pn)
76 return x2nrealloc (p, pn, 1);
79 /* Allocate S bytes of zeroed memory dynamically, with error checking.
80 There's no need for xnzalloc (N, S), since it would be equivalent
86 return memset (xmalloc (s), 0, s);
89 /* Allocate zeroed memory for N elements of S bytes, with error
90 checking. S must be nonzero. */
93 xcalloc (size_t n, size_t s)
96 /* Test for overflow, since some calloc implementations don't have
97 proper overflow checks. But omit overflow and size-zero tests if
98 HAVE_GNU_CALLOC, since GNU calloc catches overflow and never
99 returns NULL if successful. */
100 if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s))
101 || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
106 /* Clone an object P of size S, with error checking. There's no need
107 for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any
108 need for an arithmetic overflow check. */
111 xmemdup (void const *p, size_t s)
113 return memcpy (xmalloc (s), p, s);
116 /* Clone an object P of size S, with error checking, and include a
117 terminating NUL byte.
119 The terminating NUL makes it safe to use strlen or rawmemchr to
120 check for embedded NUL; it also speeds up algorithms such as escape
121 sequence processing on arbitrary memory, by making it always safe
122 to read the byte after the escape character rather than having to
123 check if each escape character is the last byte in the object. */
126 xmemdup0 (void const *p, size_t s)
128 char *result = xcharalloc (s + 1);
129 memcpy (result, p, s);
137 xstrdup (char const *string)
139 return xmemdup (string, strlen (string) + 1);