overflow_discovery/commons/pcap/pcap.go

package pcap

import (
	"sync"
	"time"

	"git.loafle.net/overflow/overflow_discovery/api/module/discovery/model"
)

var mtx sync.Mutex
var instances map[string]PCapScanner

func init() {
	instances = make(map[string]PCapScanner, 0)
}

func RetainScanner(zone *model.Zone) (PCapScanner, error) {
	mtx.Lock()
	defer mtx.Unlock()

	var ps PCapScanner
	var ok bool
	if ps, ok = instances[zone.Network]; !ok {
		ps = newPCapScanner(zone)
		if err := ps.start(); nil != err {
			return nil, err
		}
		instances[zone.Network] = ps
	}
	ps.retain()

	return ps, nil
}

func ReleaseScanner(zone *model.Zone) {

	go func() {
		time.Sleep(2 * time.Second)

		mtx.Lock()
		defer mtx.Unlock()

		if ps, ok := instances[zone.Network]; ok {
			if ps.release() {
				ps.stop()
				delete(instances, zone.Network)
			}
		}
	}()
}

func ReleaseScannerAll() {
	mtx.Lock()
	defer mtx.Unlock()

	for k, ps := range instances {
		ps.stop()
		delete(instances, k)
	}
}