blob: 72cbf4a6564cb2792bbd9ab343ea5205f76b140a [file] [log] [blame]
Girish Gowdra64503432020-01-07 10:59:10 +05301package bitmap
2
3import (
4 "sync/atomic"
5 "unsafe"
6)
7
8// SetAtomicUint32 sets the target bit to the target value inside the uint32
9// encded bitmap.
10func SetAtomicUint32(bitmap []uint32, targetBit int, targetValue bool) {
11 targetIndex := targetBit / 32
12 BitOffset := targetBit % 32
13
14 for {
15 localValue := atomic.LoadUint32(&bitmap[targetIndex])
16 targetBytes := (*[4]byte)(unsafe.Pointer(&localValue))[:]
17 if Get(targetBytes, BitOffset) == targetValue {
18 return
19 }
20 referenceValue := localValue
21 Set(targetBytes, BitOffset, targetValue)
22 if atomic.CompareAndSwapUint32(&bitmap[targetIndex], referenceValue, localValue) {
23 break
24 }
25 }
26}
27
28// GetAtomicUint32 gets the target bit from an uint32 encoded bitmap.
29func GetAtomicUint32(bitmap []uint32, targetBit int) bool {
30 data := (*[4]byte)(unsafe.Pointer(&bitmap[targetBit/32]))[:]
31 return Get(data, targetBit%32)
32}