diff options
Diffstat (limited to 'vendor/codeberg.org/gruf/go-atomics/interface.go')
-rw-r--r-- | vendor/codeberg.org/gruf/go-atomics/interface.go | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/vendor/codeberg.org/gruf/go-atomics/interface.go b/vendor/codeberg.org/gruf/go-atomics/interface.go new file mode 100644 index 000000000..f0d1c4355 --- /dev/null +++ b/vendor/codeberg.org/gruf/go-atomics/interface.go @@ -0,0 +1,57 @@ +package atomics + +import ( + "sync/atomic" + "unsafe" +) + +// Interface provides user-friendly means of performing atomic operations on interface{} types. +type Interface struct{ ptr unsafe.Pointer } + +// NewInterface will return a new Interface instance initialized with zero value. +func NewInterface() *Interface { + var v interface{} + return &Interface{ + ptr: unsafe.Pointer(&v), + } +} + +// Store will atomically store interface{} value in address contained within v. +func (v *Interface) Store(val interface{}) { + atomic.StorePointer(&v.ptr, unsafe.Pointer(&val)) +} + +// Load will atomically load interface{} value at address contained within v. +func (v *Interface) Load() interface{} { + return *(*interface{})(atomic.LoadPointer(&v.ptr)) +} + +// CAS performs a compare-and-swap for a(n) interface{} value at address contained within v. +func (v *Interface) CAS(cmp, swp interface{}) bool { + for { + // Load current value at address + ptr := atomic.LoadPointer(&v.ptr) + cur := *(*interface{})(ptr) + + // Perform comparison against current + if !(cur == cmp) { + return false + } + + // Attempt to replace pointer + if atomic.CompareAndSwapPointer( + &v.ptr, + ptr, + unsafe.Pointer(&swp), + ) { + return true + } + } +} + +// Swap atomically stores new interface{} value into address contained within v, and returns previous value. +func (v *Interface) Swap(swp interface{}) interface{} { + ptr := unsafe.Pointer(&swp) + ptr = atomic.SwapPointer(&v.ptr, ptr) + return *(*interface{})(ptr) +} |