zenoh_sync/
object_pool.rs

1//
2// Copyright (c) 2023 ZettaScale Technology
3//
4// This program and the accompanying materials are made available under the
5// terms of the Eclipse Public License 2.0 which is available at
6// http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
7// which is available at https://www.apache.org/licenses/LICENSE-2.0.
8//
9// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
10//
11// Contributors:
12//   ZettaScale Zenoh Team, <zenoh@zettascale.tech>
13//
14use std::{
15    any::Any,
16    fmt,
17    ops::{Deref, DerefMut, Drop},
18    sync::{Arc, Weak},
19};
20
21use zenoh_buffers::ZSliceBuffer;
22
23use super::LifoQueue;
24
25/// Provides a pool of pre-allocated objects that are automaticlaly reinserted into
26/// the pool when dropped.
27pub struct RecyclingObjectPool<T, F>
28where
29    F: Fn() -> T,
30{
31    inner: Arc<LifoQueue<T>>,
32    f: F,
33}
34
35impl<T, F: Fn() -> T> RecyclingObjectPool<T, F> {
36    pub fn new(num: usize, f: F) -> RecyclingObjectPool<T, F> {
37        let inner: Arc<LifoQueue<T>> = Arc::new(LifoQueue::new(num));
38        for _ in 0..num {
39            let obj = (f)();
40            inner.try_push(obj);
41        }
42        RecyclingObjectPool { inner, f }
43    }
44
45    pub fn alloc(&self) -> RecyclingObject<T> {
46        RecyclingObject::new((self.f)(), Weak::new())
47    }
48
49    pub fn try_take(&self) -> Option<RecyclingObject<T>> {
50        self.inner
51            .try_pull()
52            .map(|obj| RecyclingObject::new(obj, Arc::downgrade(&self.inner)))
53    }
54
55    pub fn take(&self) -> RecyclingObject<T> {
56        let obj = self.inner.pull();
57        RecyclingObject::new(obj, Arc::downgrade(&self.inner))
58    }
59}
60
61#[derive(Clone)]
62pub struct RecyclingObject<T> {
63    pool: Weak<LifoQueue<T>>,
64    object: Option<T>,
65}
66
67impl<T> RecyclingObject<T> {
68    pub fn new(obj: T, pool: Weak<LifoQueue<T>>) -> RecyclingObject<T> {
69        RecyclingObject {
70            pool,
71            object: Some(obj),
72        }
73    }
74
75    pub fn recycle(mut self) {
76        if let Some(pool) = self.pool.upgrade() {
77            if let Some(obj) = self.object.take() {
78                pool.push(obj);
79            }
80        }
81    }
82}
83
84impl<T: PartialEq> Eq for RecyclingObject<T> {}
85
86impl<T: PartialEq> PartialEq for RecyclingObject<T> {
87    fn eq(&self, other: &Self) -> bool {
88        self.object == other.object
89    }
90}
91
92impl<T> Deref for RecyclingObject<T> {
93    type Target = T;
94    #[inline]
95    fn deref(&self) -> &Self::Target {
96        self.object.as_ref().unwrap()
97    }
98}
99
100impl<T> DerefMut for RecyclingObject<T> {
101    #[inline]
102    fn deref_mut(&mut self) -> &mut Self::Target {
103        self.object.as_mut().unwrap()
104    }
105}
106
107impl<T> From<T> for RecyclingObject<T> {
108    fn from(obj: T) -> RecyclingObject<T> {
109        RecyclingObject::new(obj, Weak::new())
110    }
111}
112
113impl<T> Drop for RecyclingObject<T> {
114    fn drop(&mut self) {
115        if let Some(pool) = self.pool.upgrade() {
116            if let Some(obj) = self.object.take() {
117                pool.push(obj);
118            }
119        }
120    }
121}
122
123impl<T: fmt::Debug> fmt::Debug for RecyclingObject<T> {
124    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
125        f.debug_struct("").field("inner", &self.object).finish()
126    }
127}
128
129// Buffer impl
130impl AsRef<[u8]> for RecyclingObject<Box<[u8]>> {
131    fn as_ref(&self) -> &[u8] {
132        self.deref()
133    }
134}
135
136impl AsMut<[u8]> for RecyclingObject<Box<[u8]>> {
137    fn as_mut(&mut self) -> &mut [u8] {
138        self.deref_mut()
139    }
140}
141
142impl ZSliceBuffer for RecyclingObject<Box<[u8]>> {
143    fn as_slice(&self) -> &[u8] {
144        self.as_ref()
145    }
146
147    fn as_any(&self) -> &dyn Any {
148        self
149    }
150
151    fn as_any_mut(&mut self) -> &mut dyn Any {
152        self
153    }
154}
zenoh_sync/object_pool.rs

zenoh_sync/
object_pool.rs
