| 1 | /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ |
| 2 | #ifndef _LINUX_STDDEF_H |
| 3 | #define _LINUX_STDDEF_H |
| 4 | |
| 5 | |
| 6 | #ifndef __always_inline |
| 7 | #define __always_inline __inline__ |
| 8 | #endif |
| 9 | |
| 10 | /* Not all C++ standards support type declarations inside an anonymous union */ |
| 11 | #ifndef __cplusplus |
| 12 | #define __struct_group_tag(TAG) TAG |
| 13 | #else |
| 14 | #define __struct_group_tag(TAG) |
| 15 | #endif |
| 16 | |
| 17 | /** |
| 18 | * __struct_group() - Create a mirrored named and anonyomous struct |
| 19 | * |
| 20 | * @TAG: The tag name for the named sub-struct (usually empty) |
| 21 | * @NAME: The identifier name of the mirrored sub-struct |
| 22 | * @ATTRS: Any struct attributes (usually empty) |
| 23 | * @MEMBERS: The member declarations for the mirrored structs |
| 24 | * |
| 25 | * Used to create an anonymous union of two structs with identical layout |
| 26 | * and size: one anonymous and one named. The former's members can be used |
| 27 | * normally without sub-struct naming, and the latter can be used to |
| 28 | * reason about the start, end, and size of the group of struct members. |
| 29 | * The named struct can also be explicitly tagged for layer reuse (C only), |
| 30 | * as well as both having struct attributes appended. |
| 31 | */ |
| 32 | #define __struct_group(TAG, NAME, ATTRS, MEMBERS...) \ |
| 33 | union { \ |
| 34 | struct { MEMBERS } ATTRS; \ |
| 35 | struct __struct_group_tag(TAG) { MEMBERS } ATTRS NAME; \ |
| 36 | } ATTRS |
| 37 | |
| 38 | #ifdef __cplusplus |
| 39 | /* sizeof(struct{}) is 1 in C++, not 0, can't use C version of the macro. */ |
| 40 | #define __DECLARE_FLEX_ARRAY(T, member) \ |
| 41 | T member[0] |
| 42 | #else |
| 43 | /** |
| 44 | * __DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union |
| 45 | * |
| 46 | * @TYPE: The type of each flexible array element |
| 47 | * @NAME: The name of the flexible array member |
| 48 | * |
| 49 | * In order to have a flexible array member in a union or alone in a |
| 50 | * struct, it needs to be wrapped in an anonymous struct with at least 1 |
| 51 | * named member, but that member can be empty. |
| 52 | */ |
| 53 | #define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ |
| 54 | struct { \ |
| 55 | struct { } __empty_ ## NAME; \ |
| 56 | TYPE NAME[]; \ |
| 57 | } |
| 58 | #endif |
| 59 | |
| 60 | #ifndef __counted_by |
| 61 | #define __counted_by(m) |
| 62 | #endif |
| 63 | |
| 64 | #ifndef __counted_by_le |
| 65 | #define __counted_by_le(m) |
| 66 | #endif |
| 67 | |
| 68 | #ifndef __counted_by_be |
| 69 | #define __counted_by_be(m) |
| 70 | #endif |
| 71 | |
| 72 | #ifndef __counted_by_ptr |
| 73 | #define __counted_by_ptr(m) |
| 74 | #endif |
| 75 | |
| 76 | #define __kernel_nonstring |
| 77 | |
| 78 | #endif /* _LINUX_STDDEF_H */ |