1 | /* xmalloc.c -- malloc with out of memory checking |
2 | |
3 | Copyright (C) 1990-2000, 2002-2006, 2008-2019 Free Software Foundation, Inc. |
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 3 of the License, or |
8 | (at your option) 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, see <https://www.gnu.org/licenses/>. */ |
17 | |
18 | #include <config.h> |
19 | |
20 | #define XALLOC_INLINE _GL_EXTERN_INLINE |
21 | |
22 | #include "xalloc.h" |
23 | |
24 | #include <stdlib.h> |
25 | #include <string.h> |
26 | |
27 | /* 1 if calloc is known to be compatible with GNU calloc. This |
28 | matters if we are not also using the calloc module, which defines |
29 | HAVE_CALLOC_GNU and supports the GNU API even on non-GNU platforms. */ |
30 | #if defined HAVE_CALLOC_GNU || (defined __GLIBC__ && !defined __UCLIBC__) |
31 | enum { HAVE_GNU_CALLOC = 1 }; |
32 | #else |
33 | enum { HAVE_GNU_CALLOC = 0 }; |
34 | #endif |
35 | |
36 | /* Allocate N bytes of memory dynamically, with error checking. */ |
37 | |
38 | void * |
39 | xmalloc (size_t n) |
40 | { |
41 | void *p = malloc (n); |
42 | if (!p && n != 0) |
43 | xalloc_die (); |
44 | return p; |
45 | } |
46 | |
47 | /* Change the size of an allocated block of memory P to N bytes, |
48 | with error checking. */ |
49 | |
50 | void * |
51 | xrealloc (void *p, size_t n) |
52 | { |
53 | if (!n && p) |
54 | { |
55 | /* The GNU and C99 realloc behaviors disagree here. Act like |
56 | GNU, even if the underlying realloc is C99. */ |
57 | free (p); |
58 | return NULL; |
59 | } |
60 | |
61 | p = realloc (p, n); |
62 | if (!p && n) |
63 | xalloc_die (); |
64 | return p; |
65 | } |
66 | |
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. */ |
72 | |
73 | void * |
74 | x2realloc (void *p, size_t *pn) |
75 | { |
76 | return x2nrealloc (p, pn, 1); |
77 | } |
78 | |
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 |
81 | to xcalloc (N, S). */ |
82 | |
83 | void * |
84 | xzalloc (size_t s) |
85 | { |
86 | return memset (xmalloc (s), 0, s); |
87 | } |
88 | |
89 | /* Allocate zeroed memory for N elements of S bytes, with error |
90 | checking. S must be nonzero. */ |
91 | |
92 | void * |
93 | xcalloc (size_t n, size_t s) |
94 | { |
95 | void *p; |
96 | /* Test for overflow, since objects with size greater than |
97 | PTRDIFF_MAX cause pointer subtraction to go awry. Omit size-zero |
98 | tests if HAVE_GNU_CALLOC, since GNU calloc never returns NULL if |
99 | successful. */ |
100 | if (xalloc_oversized (n, s) |
101 | || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0))) |
102 | xalloc_die (); |
103 | return p; |
104 | } |
105 | |
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. */ |
109 | |
110 | void * |
111 | xmemdup (void const *p, size_t s) |
112 | { |
113 | return memcpy (xmalloc (s), p, s); |
114 | } |
115 | |
116 | /* Clone STRING. */ |
117 | |
118 | char * |
119 | xstrdup (char const *string) |
120 | { |
121 | return xmemdup (string, strlen (string) + 1); |
122 | } |
123 | |