1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
use crate::ZeroCopyBuf;
use futures::Future;
use std::collections::HashMap;
use std::pin::Pin;
use std::rc::Rc;
use std::sync::RwLock;
pub type OpId = u32;
pub type Buf = Box<[u8]>;
pub type OpAsyncFuture<E> = Pin<Box<dyn Future<Output = Result<Buf, E>>>>;
pub(crate) type PendingOpFuture =
Pin<Box<dyn Future<Output = Result<(OpId, Buf), CoreError>>>>;
pub type OpResult<E> = Result<Op<E>, E>;
pub enum Op<E> {
Sync(Buf),
Async(OpAsyncFuture<E>),
AsyncUnref(OpAsyncFuture<E>),
}
pub type CoreError = ();
pub type CoreOp = Op<CoreError>;
pub type OpDispatcher = dyn Fn(&[u8], Option<ZeroCopyBuf>) -> CoreOp + 'static;
#[derive(Default)]
pub struct OpRegistry {
dispatchers: RwLock<Vec<Rc<OpDispatcher>>>,
name_to_id: RwLock<HashMap<String, OpId>>,
}
impl OpRegistry {
pub fn new() -> Self {
let registry = Self::default();
let op_id = registry.register("ops", |_, _| {
unreachable!()
});
assert_eq!(op_id, 0);
registry
}
pub fn register<F>(&self, name: &str, op: F) -> OpId
where
F: Fn(&[u8], Option<ZeroCopyBuf>) -> CoreOp + 'static,
{
let mut lock = self.dispatchers.write().unwrap();
let op_id = lock.len() as u32;
let mut name_lock = self.name_to_id.write().unwrap();
let existing = name_lock.insert(name.to_string(), op_id);
assert!(
existing.is_none(),
format!("Op already registered: {}", name)
);
lock.push(Rc::new(op));
drop(name_lock);
drop(lock);
op_id
}
fn json_map(&self) -> Buf {
let lock = self.name_to_id.read().unwrap();
let op_map_json = serde_json::to_string(&*lock).unwrap();
op_map_json.as_bytes().to_owned().into_boxed_slice()
}
pub fn call(
&self,
op_id: OpId,
control: &[u8],
zero_copy_buf: Option<ZeroCopyBuf>,
) -> Option<CoreOp> {
if op_id == 0 {
return Some(Op::Sync(self.json_map()));
}
let lock = self.dispatchers.read().unwrap();
if let Some(op) = lock.get(op_id as usize) {
let op_ = Rc::clone(&op);
drop(lock);
Some(op_(control, zero_copy_buf))
} else {
None
}
}
}
#[test]
fn test_op_registry() {
use std::sync::atomic;
use std::sync::Arc;
let op_registry = OpRegistry::new();
let c = Arc::new(atomic::AtomicUsize::new(0));
let c_ = c.clone();
let test_id = op_registry.register("test", move |_, _| {
c_.fetch_add(1, atomic::Ordering::SeqCst);
CoreOp::Sync(Box::new([]))
});
assert!(test_id != 0);
let mut expected = HashMap::new();
expected.insert("ops".to_string(), 0);
expected.insert("test".to_string(), 1);
let name_to_id = op_registry.name_to_id.read().unwrap();
assert_eq!(*name_to_id, expected);
let res = op_registry.call(test_id, &[], None).unwrap();
if let Op::Sync(buf) = res {
assert_eq!(buf.len(), 0);
} else {
unreachable!();
}
assert_eq!(c.load(atomic::Ordering::SeqCst), 1);
let res = op_registry.call(100, &[], None);
assert!(res.is_none());
}
#[test]
fn register_op_during_call() {
use std::sync::atomic;
use std::sync::Arc;
let op_registry = Arc::new(OpRegistry::new());
let c = Arc::new(atomic::AtomicUsize::new(0));
let c_ = c.clone();
let op_registry_ = op_registry.clone();
let test_id = op_registry.register("dynamic_register_op", move |_, _| {
let c__ = c_.clone();
op_registry_.register("test", move |_, _| {
c__.fetch_add(1, atomic::Ordering::SeqCst);
CoreOp::Sync(Box::new([]))
});
CoreOp::Sync(Box::new([]))
});
assert!(test_id != 0);
op_registry.call(test_id, &[], None);
let mut expected = HashMap::new();
expected.insert("ops".to_string(), 0);
expected.insert("dynamic_register_op".to_string(), 1);
expected.insert("test".to_string(), 2);
let name_to_id = op_registry.name_to_id.read().unwrap();
assert_eq!(*name_to_id, expected);
let res = op_registry.call(2, &[], None).unwrap();
if let Op::Sync(buf) = res {
assert_eq!(buf.len(), 0);
} else {
unreachable!();
}
assert_eq!(c.load(atomic::Ordering::SeqCst), 1);
let res = op_registry.call(100, &[], None);
assert!(res.is_none());
}