27 lines
724 B
Rust
27 lines
724 B
Rust
use core::sync::atomic::{fence, AtomicI32, Ordering};
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#[repr(transparent)]
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#[derive(Default)]
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pub struct RefCount(pub(crate) AtomicI32);
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impl RefCount {
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pub fn new(count: u32) -> Self {
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Self(AtomicI32::new(count as i32))
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}
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pub fn add_ref(&self) -> u32 {
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(self.0.fetch_add(1, Ordering::Relaxed) + 1) as u32
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}
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pub fn release(&self) -> u32 {
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let remaining = self.0.fetch_sub(1, Ordering::Release) - 1;
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match remaining.cmp(&0) {
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core::cmp::Ordering::Equal => fence(Ordering::Acquire),
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core::cmp::Ordering::Less => panic!("Object has been over-released."),
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core::cmp::Ordering::Greater => {}
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}
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remaining as u32
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}
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}
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