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
|
package graphdriver
import "sync"
type minfo struct {
check bool
count int
}
// RefCounter is a generic counter for use by graphdriver Get/Put calls
type RefCounter struct {
counts map[string]*minfo
mu sync.Mutex
checker Checker
}
// NewRefCounter returns a new RefCounter
func NewRefCounter(c Checker) *RefCounter {
return &RefCounter{
checker: c,
counts: make(map[string]*minfo),
}
}
// Increment increases the ref count for the given id and returns the current count
func (c *RefCounter) Increment(path string) int {
return c.incdec(path, func(minfo *minfo) {
minfo.count++
})
}
// Decrement decreases the ref count for the given id and returns the current count
func (c *RefCounter) Decrement(path string) int {
return c.incdec(path, func(minfo *minfo) {
minfo.count--
})
}
func (c *RefCounter) incdec(path string, infoOp func(minfo *minfo)) int {
c.mu.Lock()
m := c.counts[path]
if m == nil {
m = &minfo{}
c.counts[path] = m
}
// if we are checking this path for the first time check to make sure
// if it was already mounted on the system and make sure we have a correct ref
// count if it is mounted as it is in use.
if !m.check {
m.check = true
if c.checker.IsMounted(path) {
m.count++
}
} else if !c.checker.IsMounted(path) {
// if the unmount was performed outside of this process (e.g. conmon cleanup)
//the ref counter would lose track of it. Check if it is still mounted.
m.count = 0
}
infoOp(m)
count := m.count
c.mu.Unlock()
return count
}
|
