vendor/github.com/tendermint/tmlibs/autofile/sighup_watcher.go

   1 package autofile
   2
   3 import (
   4         "os"
   5         "os/signal"
   6         "sync"
   7         "sync/atomic"
   8         "syscall"
   9 )
  10
  11 func init() {
  12         initSighupWatcher()
  13 }
  14
  15 var sighupWatchers *SighupWatcher
  16 var sighupCounter int32 // For testing
  17
  18 func initSighupWatcher() {
  19         sighupWatchers = newSighupWatcher()
  20
  21         c := make(chan os.Signal, 1)
  22         signal.Notify(c, syscall.SIGHUP)
  23
  24         go func() {
  25                 for range c {
  26                         sighupWatchers.closeAll()
  27                         atomic.AddInt32(&sighupCounter, 1)
  28                 }
  29         }()
  30 }
  31
  32 // Watchces for SIGHUP events and notifies registered AutoFiles
  33 type SighupWatcher struct {
  34         mtx       sync.Mutex
  35         autoFiles map[string]*AutoFile
  36 }
  37
  38 func newSighupWatcher() *SighupWatcher {
  39         return &SighupWatcher{
  40                 autoFiles: make(map[string]*AutoFile, 10),
  41         }
  42 }
  43
  44 func (w *SighupWatcher) addAutoFile(af *AutoFile) {
  45         w.mtx.Lock()
  46         w.autoFiles[af.ID] = af
  47         w.mtx.Unlock()
  48 }
  49
  50 // If AutoFile isn't registered or was already removed, does nothing.
  51 func (w *SighupWatcher) removeAutoFile(af *AutoFile) {
  52         w.mtx.Lock()
  53         delete(w.autoFiles, af.ID)
  54         w.mtx.Unlock()
  55 }
  56
  57 func (w *SighupWatcher) closeAll() {
  58         w.mtx.Lock()
  59         for _, af := range w.autoFiles {
  60                 af.closeFile()
  61         }
  62         w.mtx.Unlock()
  63 }