1use crate::backend::{Address, BackendState};
2use crate::error::Error;
3use crate::strategy::LbStrategy;
4use std::sync::Arc;
5use std::sync::atomic::Ordering::Relaxed;
6use std::sync::atomic::{AtomicU64, AtomicUsize};
7use std::time::Duration;
8
9pub trait Pool: Send + Sync {
10 fn id(&self) -> &str {
12 ""
13 }
14
15 fn set_max_conn(&self, max: Option<usize>);
17
18 fn get_max_conn(&self) -> Option<usize>;
20
21 fn get_cur_conn(&self) -> usize;
23
24 fn set_keepalive(&self, _: Option<Duration>) {}
26
27 fn get_keepalive(&self) -> Option<Duration> {
29 None
30 }
31
32 fn get_strategy(&self) -> Arc<dyn LbStrategy>;
34
35 fn add_backend(&self, addr: Address) {
37 self.get_strategy().add_backend(addr)
38 }
39
40 fn remove_backend(&self, addr: &Address) -> bool {
42 self.get_strategy().remove_backend(addr)
43 }
44
45 fn get_backends(&self) -> Vec<BackendState> {
47 self.get_strategy().get_backends()
48 }
49
50 fn use_tls(&self, _: bool) {}
52
53 fn tls(&self) -> bool {
54 false
55 }
56}
57
58pub struct BaseState {
59 pub max_conn: AtomicUsize, pub cur_conn: AtomicUsize,
61 pub keepalive: AtomicU64, pub lb_strategy: Arc<dyn LbStrategy>,
63}
64
65impl BaseState {
66 pub fn new(strategy: Arc<dyn LbStrategy>) -> Self {
67 BaseState {
68 max_conn: AtomicUsize::new(usize::MAX),
69 cur_conn: AtomicUsize::new(0),
70 keepalive: AtomicU64::new(u64::MAX),
71 lb_strategy: strategy,
72 }
73 }
74}
75
76pub fn increase_current(max: &AtomicUsize, cur: &AtomicUsize) -> Result<(), Error> {
77 let m = max.load(Relaxed);
78 if m == usize::MAX {
79 cur.fetch_add(1, Relaxed);
80 Ok(())
81 } else {
82 let mut c = cur.load(Relaxed);
83 loop {
84 if c == m {
85 break Err(Error::PoolFull);
86 }
87
88 match cur.compare_exchange(c, c + 1, Relaxed, Relaxed) {
89 Ok(_) => break Ok(()),
90 Err(s) => c = s,
91 }
92 }
93 }
94}