|
Packit Service |
a2ae7a |
/* Sizes of structs with flexible array members.
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
Copyright 2016-2019 Free Software Foundation, Inc.
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
This file is part of the GNU C Library.
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
The GNU C Library is free software; you can redistribute it and/or
|
|
Packit Service |
a2ae7a |
modify it under the terms of the GNU Lesser General Public
|
|
Packit Service |
a2ae7a |
License as published by the Free Software Foundation; either
|
|
Packit Service |
a2ae7a |
version 2.1 of the License, or (at your option) any later version.
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
The GNU C Library is distributed in the hope that it will be useful,
|
|
Packit Service |
a2ae7a |
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
Packit Service |
a2ae7a |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Packit Service |
a2ae7a |
Lesser General Public License for more details.
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
You should have received a copy of the GNU Lesser General Public
|
|
Packit Service |
a2ae7a |
License along with the GNU C Library; if not, see
|
|
Packit Service |
a2ae7a |
<https://www.gnu.org/licenses/>.
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
Written by Paul Eggert. */
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
#include <stddef.h>
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
/* Nonzero multiple of alignment of TYPE, suitable for FLEXSIZEOF below.
|
|
Packit Service |
a2ae7a |
On older platforms without _Alignof, use a pessimistic bound that is
|
|
Packit Service |
a2ae7a |
safe in practice even if FLEXIBLE_ARRAY_MEMBER is 1.
|
|
Packit Service |
a2ae7a |
On newer platforms, use _Alignof to get a tighter bound. */
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112
|
|
Packit Service |
a2ae7a |
# define FLEXALIGNOF(type) (sizeof (type) & ~ (sizeof (type) - 1))
|
|
Packit Service |
a2ae7a |
#else
|
|
Packit Service |
a2ae7a |
# define FLEXALIGNOF(type) _Alignof (type)
|
|
Packit Service |
a2ae7a |
#endif
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
/* Upper bound on the size of a struct of type TYPE with a flexible
|
|
Packit Service |
a2ae7a |
array member named MEMBER that is followed by N bytes of other data.
|
|
Packit Service |
a2ae7a |
This is not simply sizeof (TYPE) + N, since it may require
|
|
Packit Service |
a2ae7a |
alignment on unusually picky C11 platforms, and
|
|
Packit Service |
a2ae7a |
FLEXIBLE_ARRAY_MEMBER may be 1 on pre-C11 platforms.
|
|
Packit Service |
a2ae7a |
Yield a value less than N if and only if arithmetic overflow occurs. */
|
|
Packit Service |
a2ae7a |
|
|
Packit Service |
a2ae7a |
#define FLEXSIZEOF(type, member, n) \
|
|
Packit Service |
a2ae7a |
((offsetof (type, member) + FLEXALIGNOF (type) - 1 + (n)) \
|
|
Packit Service |
a2ae7a |
& ~ (FLEXALIGNOF (type) - 1))
|