syncthing/lib/discover/cache.go

69 lines
1.5 KiB
Go

// Copyright (C) 2015 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.
package discover
import (
stdsync "sync"
"time"
"github.com/thejerf/suture/v4"
"github.com/syncthing/syncthing/lib/protocol"
)
// A cachedFinder is a Finder with associated cache timeouts.
type cachedFinder struct {
Finder
cacheTime time.Duration
negCacheTime time.Duration
cache *cache
token *suture.ServiceToken
}
// An error may implement cachedError, in which case it will be interrogated
// to see how long we should cache the error. This overrides the default
// negative cache time.
type cachedError interface {
CacheFor() time.Duration
}
// A cache can be embedded wherever useful
type cache struct {
entries map[protocol.DeviceID]CacheEntry
mut stdsync.Mutex
}
func newCache() *cache {
return &cache{
entries: make(map[protocol.DeviceID]CacheEntry),
}
}
func (c *cache) Set(id protocol.DeviceID, ce CacheEntry) {
c.mut.Lock()
c.entries[id] = ce
c.mut.Unlock()
}
func (c *cache) Get(id protocol.DeviceID) (CacheEntry, bool) {
c.mut.Lock()
ce, ok := c.entries[id]
c.mut.Unlock()
return ce, ok
}
func (c *cache) Cache() map[protocol.DeviceID]CacheEntry {
c.mut.Lock()
m := make(map[protocol.DeviceID]CacheEntry, len(c.entries))
for k, v := range c.entries {
m[k] = v
}
c.mut.Unlock()
return m
}