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-rw-r--r--vendor/codeberg.org/gruf/go-atomics/string.go57
1 files changed, 57 insertions, 0 deletions
diff --git a/vendor/codeberg.org/gruf/go-atomics/string.go b/vendor/codeberg.org/gruf/go-atomics/string.go
new file mode 100644
index 000000000..a0a6e115f
--- /dev/null
+++ b/vendor/codeberg.org/gruf/go-atomics/string.go
@@ -0,0 +1,57 @@
+package atomics
+
+import (
+ "sync/atomic"
+ "unsafe"
+)
+
+// String provides user-friendly means of performing atomic operations on string types.
+type String struct{ ptr unsafe.Pointer }
+
+// NewString will return a new String instance initialized with zero value.
+func NewString() *String {
+ var v string
+ return &String{
+ ptr: unsafe.Pointer(&v),
+ }
+}
+
+// Store will atomically store string value in address contained within v.
+func (v *String) Store(val string) {
+ atomic.StorePointer(&v.ptr, unsafe.Pointer(&val))
+}
+
+// Load will atomically load string value at address contained within v.
+func (v *String) Load() string {
+ return *(*string)(atomic.LoadPointer(&v.ptr))
+}
+
+// CAS performs a compare-and-swap for a(n) string value at address contained within v.
+func (v *String) CAS(cmp, swp string) bool {
+ for {
+ // Load current value at address
+ ptr := atomic.LoadPointer(&v.ptr)
+ cur := *(*string)(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 string value into address contained within v, and returns previous value.
+func (v *String) Swap(swp string) string {
+ ptr := unsafe.Pointer(&swp)
+ ptr = atomic.SwapPointer(&v.ptr, ptr)
+ return *(*string)(ptr)
+}