/
id_allocator.go
61 lines (53 loc) · 1.36 KB
/
id_allocator.go
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
// Copyright 2021 Antrea Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package egress
import (
"container/list"
"fmt"
"sync"
)
type idAllocator struct {
sync.Mutex
maxID uint32
nextID uint32
availableIDs *list.List
}
func (a *idAllocator) allocate() (uint32, error) {
a.Lock()
defer a.Unlock()
front := a.availableIDs.Front()
if front != nil {
return a.availableIDs.Remove(front).(uint32), nil
}
if a.nextID <= a.maxID {
allocated := a.nextID
a.nextID += 1
return allocated, nil
}
return 0, fmt.Errorf("no ID available")
}
func (a *idAllocator) release(id uint32) error {
a.Lock()
defer a.Unlock()
a.availableIDs.PushBack(id)
return nil
}
func newIDAllocator(minID, maxID uint32) *idAllocator {
availableIDs := list.New()
return &idAllocator{
nextID: minID,
maxID: maxID,
availableIDs: availableIDs,
}
}