wip: migrate to mono-repo. SPN has already been moved to spn/

service/firewall/interception/introspection.go

@@ -0,0 +1,80 @@
+package interception
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/safing/portbase/log"
+)
+
+var (
+	packetMetricsDestination string
+	metrics                  = &packetMetrics{
+		done: make(chan struct{}),
+	}
+)
+
+func init() {
+	flag.StringVar(&packetMetricsDestination, "write-packet-metrics", "", "write packet metrics to the specified file")
+}
+
+type (
+	performanceRecord struct {
+		start    int64
+		duration time.Duration
+		verdict  string
+	}
+
+	packetMetrics struct {
+		done    chan struct{}
+		l       sync.Mutex
+		records []*performanceRecord
+	}
+)
+
+func (pm *packetMetrics) record(tp *tracedPacket, verdict string) {
+	go func(start int64, duration time.Duration) {
+		pm.l.Lock()
+		defer pm.l.Unlock()
+
+		pm.records = append(pm.records, &performanceRecord{
+			start:    start,
+			duration: duration,
+			verdict:  verdict,
+		})
+	}(tp.start.UnixNano(), time.Since(tp.start))
+}
+
+func (pm *packetMetrics) writeMetrics() {
+	if packetMetricsDestination == "" {
+		return
+	}
+
+	f, err := os.Create(packetMetricsDestination)
+	if err != nil {
+		log.Errorf("Failed to create packet metrics file: %s", err)
+		return
+	}
+	defer func() {
+		_ = f.Close()
+	}()
+
+	for {
+		select {
+		case <-pm.done:
+			return
+		case <-time.After(time.Second * 5):
+		}
+		pm.l.Lock()
+		records := pm.records
+		pm.records = nil
+		pm.l.Unlock()
+
+		for _, r := range records {
+			fmt.Fprintf(f, "%d;%s;%s;%.2f\n", r.start, r.verdict, r.duration, float64(r.duration)/float64(time.Microsecond))
+		}
+	}
+}