e9a0ef49f9
# Objective The goal of `bevy_platform_support` is to provide a set of platform agnostic APIs, alongside platform-specific functionality. This is a high traffic crate (providing things like HashMap and Instant). Especially in light of https://github.com/bevyengine/bevy/discussions/18799, it deserves a friendlier / shorter name. Given that it hasn't had a full release yet, getting this change in before Bevy 0.16 makes sense. ## Solution - Rename `bevy_platform_support` to `bevy_platform`.
36 lines
869 B
Rust
36 lines
869 B
Rust
use bevy_platform::sync::atomic::{AtomicBool, Ordering};
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/// Wrapper around an [`AtomicBool`], abstracting the backing implementation and
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/// ordering considerations.
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#[doc(hidden)]
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pub struct OnceFlag(AtomicBool);
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impl OnceFlag {
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/// Create a new flag in the unset state.
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pub const fn new() -> Self {
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Self(AtomicBool::new(true))
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}
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/// Sets this flag. Will return `true` if this flag hasn't been set before.
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pub fn set(&self) -> bool {
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self.0.swap(false, Ordering::Relaxed)
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}
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}
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impl Default for OnceFlag {
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fn default() -> Self {
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Self::new()
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}
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}
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/// Call some expression only once per call site.
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#[macro_export]
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macro_rules! once {
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($expression:expr) => {{
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static SHOULD_FIRE: $crate::OnceFlag = $crate::OnceFlag::new();
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if SHOULD_FIRE.set() {
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$expression;
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}
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}};
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}
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