| commit | 3e65d5ae110ca56ba687ba01a02c856abf61d3b8 | [log] [tgz] |
|---|---|---|
| author | Janis Danisevskis <[email protected]> | Mon Nov 15 22:51:24 2021 +0000 |
| committer | Automerger Merge Worker <[email protected]> | Mon Nov 15 22:51:24 2021 +0000 |
| tree | 440e8cad7d8e81208069a87cf2d47e9e892e4285 | |
| parent | 0cfa9b2c4837dadbae981a4ca0de107f87d11492 [diff] | |
| parent | 229f1375465da0821645586be857438958c1d52d [diff] |
Make vendor available. am: 229f137546 Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/memoffset/+/1886665 Change-Id: Ie72b3f0a91e64c166cbc78d71ed0a7cee64045b6
C-Like offset_of functionality for Rust structs.
Introduces the following macros:
offset_of! for obtaining the offset of a member of a struct.offset_of_tuple! for obtaining the offset of a member of a tuple. (Requires Rust 1.20+)span_of! for obtaining the range that a field, or fields, span.memoffset works under no_std environments.
Add the following dependency to your Cargo.toml:
[dependencies] memoffset = "0.6"
These versions will compile fine with rustc versions greater or equal to 1.19.
Add the following lines at the top of your main.rs or lib.rs files.
#[macro_use] extern crate memoffset;
#[macro_use] extern crate memoffset; #[repr(C, packed)] struct Foo { a: u32, b: u32, c: [u8; 5], d: u32, } fn main() { assert_eq!(offset_of!(Foo, b), 4); assert_eq!(offset_of!(Foo, d), 4+4+5); assert_eq!(span_of!(Foo, a), 0..4); assert_eq!(span_of!(Foo, a .. c), 0..8); assert_eq!(span_of!(Foo, a ..= c), 0..13); assert_eq!(span_of!(Foo, ..= d), 0..17); assert_eq!(span_of!(Foo, b ..), 4..17); }
memoffset has experimental support for compile-time offset_of! on a nightly compiler.
In order to use it, you must enable the unstable_const crate feature and several compiler features.
Cargo.toml:
[dependencies.memoffset] version = "0.6" features = ["unstable_const"]
Your crate root: (lib.rs/main.rs)
#![feature(const_ptr_offset_from, const_maybe_uninit_as_ptr, const_raw_ptr_deref, const_refs_to_cell)]