diff --git a/internal/filtering/filter.go b/internal/filtering/filter.go index 169b2d51..64befc73 100644 --- a/internal/filtering/filter.go +++ b/internal/filtering/filter.go @@ -263,30 +263,6 @@ func assignUniqueFilterID() int64 { return value } -// Sets up a timer that will be checking for filters updates periodically -func (d *DNSFilter) periodicallyRefreshFilters() { - const maxInterval = 1 * 60 * 60 - ivl := 5 // use a dynamically increasing time interval - for { - isNetErr, ok := false, false - if d.conf.FiltersUpdateIntervalHours != 0 { - _, isNetErr, ok = d.tryRefreshFilters(true, true, false) - if ok && !isNetErr { - ivl = maxInterval - } - } - - if isNetErr { - ivl *= 2 - if ivl > maxInterval { - ivl = maxInterval - } - } - - time.Sleep(time.Duration(ivl) * time.Second) - } -} - // tryRefreshFilters is like [refreshFilters], but backs down if the update is // already going on. // diff --git a/internal/filtering/filtering.go b/internal/filtering/filtering.go index c9f52dfc..6fae9c60 100644 --- a/internal/filtering/filtering.go +++ b/internal/filtering/filtering.go @@ -257,6 +257,9 @@ type DNSFilter struct { // conf contains filtering parameters. conf *Config + // done is the channel to signal to stop running filters updates loop. + done chan struct{} + // Channel for passing data to filters-initializer goroutine filtersInitializerChan chan filtersInitializerParams filtersInitializerLock sync.Mutex @@ -424,24 +427,15 @@ func (d *DNSFilter) setFilters(blockFilters, allowFilters []Filter, async bool) return d.initFiltering(allowFilters, blockFilters) } -// Starts initializing new filters by signal from channel -func (d *DNSFilter) filtersInitializer() { - for { - params := <-d.filtersInitializerChan - err := d.initFiltering(params.allowFilters, params.blockFilters) - if err != nil { - log.Error("filtering: initializing: %s", err) - - continue - } - } -} - // Close - close the object func (d *DNSFilter) Close() { d.engineLock.Lock() defer d.engineLock.Unlock() + if d.done != nil { + d.done <- struct{}{} + } + d.reset() } @@ -1131,19 +1125,64 @@ func New(c *Config, blockFilters []Filter) (d *DNSFilter, err error) { return d, nil } -// Start - start the module: -// . start async filtering initializer goroutine -// . register web handlers +// Start registers web handlers and starts filters updates loop. func (d *DNSFilter) Start() { d.filtersInitializerChan = make(chan filtersInitializerParams, 1) - go d.filtersInitializer() + d.done = make(chan struct{}, 1) d.RegisterFilteringHandlers() - // Here we should start updating filters, - // but currently we can't wake up the periodic task to do so. - // So for now we just start this periodic task from here. - go d.periodicallyRefreshFilters() + go d.updatesLoop() +} + +// updatesLoop initializes new filters and checks for filters updates in a loop. +func (d *DNSFilter) updatesLoop() { + defer log.OnPanic("filtering: updates loop") + + ivl := time.Second * 5 + t := time.NewTimer(ivl) + + for { + select { + case params := <-d.filtersInitializerChan: + err := d.initFiltering(params.allowFilters, params.blockFilters) + if err != nil { + log.Error("filtering: initializing: %s", err) + + continue + } + case <-t.C: + ivl = d.periodicallyRefreshFilters(ivl) + t.Reset(ivl) + case <-d.done: + t.Stop() + + return + } + } +} + +// periodicallyRefreshFilters checks for filters updates and returns time +// interval for the next update. +func (d *DNSFilter) periodicallyRefreshFilters(ivl time.Duration) (nextIvl time.Duration) { + const maxInterval = time.Hour + + if d.conf.FiltersUpdateIntervalHours == 0 { + return ivl + } + + isNetErr, ok := false, false + _, isNetErr, ok = d.tryRefreshFilters(true, true, false) + + if ok && !isNetErr { + ivl = maxInterval + } else if isNetErr { + ivl *= 2 + // TODO(s.chzhen): Use built-in function max in Go 1.21. + ivl = mathutil.Max(ivl, maxInterval) + } + + return ivl } // Safe browsing and parental control methods.