Improve JSON and regular output, especially when comm or pid are empty.

Author: dkorunic

output.go

@@ -33,12 +33,11 @@ import (
 )
 
 const (
-	Bps        float64 = 1.0
-	Kbps               = 1000 * Bps
-	Mbps               = 1000 * Kbps
-	Gbps               = 1000 * Mbps
-	Tbps               = 1000 * Gbps
-	KernelComm         = "[kernel]"
+	Bps  float64 = 1.0
+	Kbps         = 1000 * Bps
+	Mbps         = 1000 * Kbps
+	Gbps         = 1000 * Mbps
+	Tbps         = 1000 * Gbps
 )
 
 // processMap generates statEntry objects from an ebpf.Map using the provided start time.
@@ -121,7 +120,11 @@ func outputPlain(m []statEntry) {
 		}
 
 		if *useKProbes {
-			sb.WriteString(fmt.Sprintf(", pid: %d, comm: %v", v.Pid, v.Comm))
+			sb.WriteString(fmt.Sprintf(", pid: %d", v.Pid))
+
+			if v.Comm != "" {
+				sb.WriteString(fmt.Sprintf(", comm: %v", v.Comm))
+			}
 		}
 
 		sb.WriteString("\n")
@@ -157,9 +160,5 @@ func comm2String(bs []int8) string {
 	// trim excess NULLs
 	b = bytes.Trim(b, "\x00")
 
-	if len(b) == 0 {
-		return KernelComm
-	}
-
 	return string(b)
 }

types.go

@@ -10,11 +10,11 @@ type statEntry struct {
 	SrcIP   netip.Addr `json:"srcIp"`
 	DstIP   netip.Addr `json:"dstIp"`
 	Proto   string     `json:"proto"`
-	Comm    string     `json:"comm"`
+	Comm    string     `json:"comm,omitempty"`
 	Bytes   uint64     `json:"bytes"`
 	Packets uint64     `json:"packets"`
 	Bitrate float64    `json:"bitrate"`
-	Pid     int32      `json:"pid"`
+	Pid     int32      `json:"pid,omitempty"`
 	SrcPort uint16     `json:"srcPort"`
 	DstPort uint16     `json:"dstPort"`
 }