github.com/pawelgaczynski/gain@v0.4.0-alpha.0.20230821120126-41f1e60a18da/shutdown.go (about)

     1  // Copyright (c) 2023 Paweł Gaczyński
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package gain
    16  
    17  import (
    18  	"sync"
    19  	"sync/atomic"
    20  )
    21  
    22  type shutdowner struct {
    23  	shutdowning atomic.Bool
    24  	inProgress  atomic.Bool
    25  	wg          sync.WaitGroup
    26  }
    27  
    28  func (s *shutdowner) markShutdownInProgress() {
    29  	s.inProgress.Store(true)
    30  }
    31  
    32  func (s *shutdowner) needToShutdown() bool {
    33  	return s.shutdowning.Load() && !s.inProgress.Load()
    34  }
    35  
    36  func (s *shutdowner) notifyFinish() {
    37  	if s.shutdowning.Load() {
    38  		s.wg.Done()
    39  	}
    40  }
    41  
    42  func (s *shutdowner) shutdown() {
    43  	s.shutdowning.Store(true)
    44  	s.wg.Add(1)
    45  	s.wg.Wait()
    46  }
    47  
    48  func newShutdowner() *shutdowner {
    49  	return &shutdowner{}
    50  }