| commit | 6def8aef466810503607ee115fc36f5b56b518c0 | [log] [tgz] |
|---|---|---|
| author | Jeff Vander Stoep <jeffv@google.com> | Mon Dec 12 18:28:54 2022 +0100 |
| committer | Jeff Vander Stoep <jeffv@google.com> | Mon Dec 12 18:29:15 2022 +0100 |
| tree | 579e9f3356eaf9c19b7f8ebb8619cdb44bc97aa8 | |
| parent | 41f53a7b2311ba3bfece38a5ae473912cf7b5312 [diff] |
Upgrade memoffset to 0.7.1 This project was upgraded with external_updater. Usage: tools/external_updater/updater.sh update rust/crates/memoffset For more info, check https://cs.android.com/android/platform/superproject/+/master:tools/external_updater/README.md Test: TreeHugger Change-Id: If34b9eaab2799a951cd1c36814af5df4cbeacf03
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 = "0.7"
These versions will compile fine with rustc versions greater or equal to 1.19.
use memoffset::{offset_of, span_of}; #[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 = "0.7" features = ["unstable_const"]
Your crate root: (lib.rs/main.rs)
#![feature(const_ptr_offset_from, const_refs_to_cell)]