1 /* Memory allocators such as malloc+free.
2
3 Copyright (C) 2011-2023 Free Software Foundation, Inc.
4
5 This file is free software: you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as
7 published by the Free Software Foundation; either version 2.1 of the
8 License, or (at your option) any later version.
9
10 This file 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 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public License
16 along with this program. If not, see <https://www.gnu.org/licenses/>. */
17
18 /* Written by Paul Eggert. */
19
20 #ifndef _GL_ALLOCATOR_H
21 #define _GL_ALLOCATOR_H
22
23 #include <stddef.h>
24
25 /* An object describing a memory allocator family. */
26
27 struct allocator
28 {
29 /* Do not use GCC attributes such as __attribute__ ((malloc)) with
30 the function types pointed at by these members, because these
31 attributes do not work with pointers to functions. See
32 <https://lists.gnu.org/r/bug-gnulib/2011-04/msg00007.html>. */
33
34 /* Call ALLOCATE to allocate memory, like 'malloc'. On failure ALLOCATE
35 should return NULL, though not necessarily set errno. When given
36 a zero size it may return NULL even if successful. */
37 void *(*allocate) (size_t);
38
39 /* If nonnull, call REALLOCATE to reallocate memory, like 'realloc'.
40 On failure REALLOCATE should return NULL, though not necessarily set
41 errno. When given a zero size it may return NULL even if
42 successful. */
43 void *(*reallocate) (void *, size_t);
44
45 /* Call FREE to free memory, like 'free'. */
46 void (*free) (void *);
47
48 /* If nonnull, call DIE (SIZE) if MALLOC (SIZE) or REALLOC (...,
49 SIZE) fails. DIE should not return. SIZE should equal SIZE_MAX
50 if size_t overflow was detected while calculating sizes to be
51 passed to MALLOC or REALLOC. */
52 void (*die) (size_t);
53 };
54
55 /* An allocator using the stdlib functions and a null DIE function. */
56 extern struct allocator const stdlib_allocator;
57
58 #endif /* _GL_ALLOCATOR_H */