1 // @generated Code generated by gen-atomicwrapper.
2 3 // Copyright (c) 2020-2023 Uber Technologies, Inc.
4 //
5 // Permission is hereby granted, free of charge, to any person obtaining a copy
6 // of this software and associated documentation files (the "Software"), to deal
7 // in the Software without restriction, including without limitation the rights
8 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9 // copies of the Software, and to permit persons to whom the Software is
10 // furnished to do so, subject to the following conditions:
11 //
12 // The above copyright notice and this permission notice shall be included in
13 // all copies or substantial portions of the Software.
14 //
15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21 // THE SOFTWARE.
22 23 package atomic
24 25 // String is an atomic type-safe wrapper for string values.
26 type String struct {
27 _ nocmp // disallow non-atomic comparison
28 29 v Value
30 }
31 32 var _zeroString string
33 34 // NewString creates a new String.
35 func NewString(val string) *String {
36 x := &String{}
37 if val != _zeroString {
38 x.Store(val)
39 }
40 return x
41 }
42 43 // Load atomically loads the wrapped string.
44 func (x *String) Load() string {
45 return unpackString(x.v.Load())
46 }
47 48 // Store atomically stores the passed string.
49 func (x *String) Store(val string) {
50 x.v.Store(packString(val))
51 }
52 53 // CompareAndSwap is an atomic compare-and-swap for string values.
54 func (x *String) CompareAndSwap(old, new string) (swapped bool) {
55 if x.v.CompareAndSwap(packString(old), packString(new)) {
56 return true
57 }
58 59 if old == _zeroString {
60 // If the old value is the empty value, then it's possible the
61 // underlying Value hasn't been set and is nil, so retry with nil.
62 return x.v.CompareAndSwap(nil, packString(new))
63 }
64 65 return false
66 }
67 68 // Swap atomically stores the given string and returns the old
69 // value.
70 func (x *String) Swap(val string) (old string) {
71 return unpackString(x.v.Swap(packString(val)))
72 }
73