commit | 073d05ba30ead6dd7d7ce29d27bc30556be6b9b0 | [log] [tgz] |
---|---|---|
author | Roopa Sattiraju <sattiraju@google.com> | Wed Dec 22 18:02:24 2021 +0000 |
committer | Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> | Wed Dec 22 18:02:24 2021 +0000 |
tree | 36bc3873a07934dd7d5791d7bcadf34d97f2e051 | |
parent | 75c7d15b760241df91048e4777943b514d6f873e [diff] | |
parent | 843af6f710aadd6f80a20c3eb18a88fbaf1d2186 [diff] |
Adding bluetooth apex am: db36f4b0cb am: 3d80bf65f6 am: b689da917c am: 843af6f710 Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/memoffset/+/1931442 Change-Id: I27368f5f7c83c7f8dcf213977e767b3edcb29dfa
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)]