75 lines
1.5 KiB
Rust
75 lines
1.5 KiB
Rust
// Copyright 2019 The Fuchsia Authors
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//
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// Licensed under a BSD-style license <LICENSE-BSD>, Apache License, Version 2.0
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// <LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0>, or the MIT
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// license <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your option.
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// This file may not be copied, modified, or distributed except according to
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// those terms.
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#![allow(warnings)]
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use std::{marker::PhantomData, option::IntoIter};
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use {static_assertions::assert_impl_all, zerocopy::AsBytes};
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// A union is `AsBytes` if:
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// - all fields are `AsBytes`
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// - `repr(C)` or `repr(transparent)` and
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// - no padding (size of union equals size of each field type)
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// - `repr(packed)`
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#[derive(AsBytes, Clone, Copy)]
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#[repr(C)]
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union CZst {
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a: (),
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}
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assert_impl_all!(CZst: AsBytes);
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#[derive(AsBytes)]
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#[repr(C)]
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union C {
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a: u8,
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b: u8,
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}
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assert_impl_all!(C: AsBytes);
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// Transparent unions are unstable; see issue #60405
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// <https://github.com/rust-lang/rust/issues/60405> for more information.
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// #[derive(AsBytes)]
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// #[repr(transparent)]
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// union Transparent {
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// a: u8,
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// b: CZst,
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// }
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// is_as_bytes!(Transparent);
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#[derive(AsBytes)]
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#[repr(C, packed)]
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union CZstPacked {
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a: (),
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}
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assert_impl_all!(CZstPacked: AsBytes);
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#[derive(AsBytes)]
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#[repr(C, packed)]
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union CPacked {
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a: u8,
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b: i8,
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}
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assert_impl_all!(CPacked: AsBytes);
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#[derive(AsBytes)]
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#[repr(C, packed)]
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union CMultibytePacked {
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a: i32,
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b: u32,
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c: f32,
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}
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assert_impl_all!(CMultibytePacked: AsBytes);
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