bool_ext.go raw

   1  // Copyright (c) 2020 Uber Technologies, Inc.
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   4  // of this software and associated documentation files (the "Software"), to deal
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   7  // copies of the Software, and to permit persons to whom the Software is
   8  // furnished to do so, subject to the following conditions:
   9  //
  10  // The above copyright notice and this permission notice shall be included in
  11  // all copies or substantial portions of the Software.
  12  //
  13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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  18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  19  // THE SOFTWARE.
  20  
  21  package atomic
  22  
  23  import (
  24  	"strconv"
  25  )
  26  
  27  //go:generate bin/gen-atomicwrapper -name=Bool -type=bool -wrapped=Uint32 -pack=boolToInt -unpack=truthy -cas -swap -json -file=bool.go
  28  
  29  func truthy(n uint32) bool {
  30  	return n == 1
  31  }
  32  
  33  func boolToInt(b bool) uint32 {
  34  	if b {
  35  		return 1
  36  	}
  37  	return 0
  38  }
  39  
  40  // Toggle atomically negates the Boolean and returns the previous value.
  41  func (b *Bool) Toggle() (old bool) {
  42  	for {
  43  		old := b.Load()
  44  		if b.CAS(old, !old) {
  45  			return old
  46  		}
  47  	}
  48  }
  49  
  50  // String encodes the wrapped value as a string.
  51  func (b *Bool) String() string {
  52  	return strconv.FormatBool(b.Load())
  53  }
  54