1 /* xmalloc.c -- malloc with out of memory checking
2
3 Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
4 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2008-2009 Free Software Foundation,
5 Inc.
6
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.
11
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.
16
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/>. */
19
20 #include <config.h>
21
22 #if ! HAVE_INLINE
23 # define static_inline
24 #endif
25 #include "xalloc.h"
26 #undef static_inline
27
28 #include <stdlib.h>
29 #include <string.h>
30
31 /* 1 if calloc is known to be compatible with GNU calloc. This
32 matters if we are not also using the calloc module, which defines
33 HAVE_CALLOC and supports the GNU API even on non-GNU platforms. */
34 #if defined HAVE_CALLOC || defined __GLIBC__
35 enum { HAVE_GNU_CALLOC = 1 };
36 #else
37 enum { HAVE_GNU_CALLOC = 0 };
38 #endif
39
40 /* Allocate N bytes of memory dynamically, with error checking. */
41
42 void *
xmalloc(size_t n)43 xmalloc (size_t n)
44 {
45 void *p = malloc (n);
46 if (!p && n != 0)
47 xalloc_die ();
48 return p;
49 }
50
51 /* Change the size of an allocated block of memory P to N bytes,
52 with error checking. */
53
54 void *
xrealloc(void * p,size_t n)55 xrealloc (void *p, size_t n)
56 {
57 p = realloc (p, n);
58 if (!p && n != 0)
59 xalloc_die ();
60 return p;
61 }
62
63 /* If P is null, allocate a block of at least *PN bytes; otherwise,
64 reallocate P so that it contains more than *PN bytes. *PN must be
65 nonzero unless P is null. Set *PN to the new block's size, and
66 return the pointer to the new block. *PN is never set to zero, and
67 the returned pointer is never null. */
68
69 void *
x2realloc(void * p,size_t * pn)70 x2realloc (void *p, size_t *pn)
71 {
72 return x2nrealloc (p, pn, 1);
73 }
74
75 /* Allocate S bytes of zeroed memory dynamically, with error checking.
76 There's no need for xnzalloc (N, S), since it would be equivalent
77 to xcalloc (N, S). */
78
79 void *
xzalloc(size_t s)80 xzalloc (size_t s)
81 {
82 return memset (xmalloc (s), 0, s);
83 }
84
85 /* Allocate zeroed memory for N elements of S bytes, with error
86 checking. S must be nonzero. */
87
88 void *
xcalloc(size_t n,size_t s)89 xcalloc (size_t n, size_t s)
90 {
91 void *p;
92 /* Test for overflow, since some calloc implementations don't have
93 proper overflow checks. But omit overflow and size-zero tests if
94 HAVE_GNU_CALLOC, since GNU calloc catches overflow and never
95 returns NULL if successful. */
96 if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s))
97 || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
98 xalloc_die ();
99 return p;
100 }
101
102 /* Clone an object P of size S, with error checking. There's no need
103 for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any
104 need for an arithmetic overflow check. */
105
106 void *
xmemdup(void const * p,size_t s)107 xmemdup (void const *p, size_t s)
108 {
109 return memcpy (xmalloc (s), p, s);
110 }
111
112 /* Clone STRING. */
113
114 char *
xstrdup(char const * string)115 xstrdup (char const *string)
116 {
117 return xmemdup (string, strlen (string) + 1);
118 }
119