Allow table sorting

Author: dkorunic

main.go

@@ -120,7 +120,7 @@ func main() {
 
 		<-c1.Done()
 
-		m, err := processMap(objs.PktCount, startTime)
+		m, err := processMap(objs.PktCount, startTime, bitrateSort)
 		if err != nil {
 			log.Fatalf("Error reading eBPF map: %v", err)
 		}

output.go

@@ -45,7 +45,7 @@ const (
 // Parameters:
 //
 //	m *ebpf.Map - the eb
-func processMap(m *ebpf.Map, start time.Time) ([]statEntry, error) {
+func processMap(m *ebpf.Map, start time.Time, sortFunc func([]statEntry)) ([]statEntry, error) {
 	var (
 		key counterStatkey
 		val counterStatvalue
@@ -71,11 +71,64 @@ func processMap(m *ebpf.Map, start time.Time) ([]statEntry, error) {
 		})
 	}
 
+	sortFunc(stats)
+
+	return stats, iter.Err()
+}
+
+// bitrateSort sorts a slice of statEntry objects by their Bitrate field in descending order.
+//
+// Parameters:
+//
+//	stats []statEntry - the slice of statEntry objects to be sorted
+func bitrateSort(stats []statEntry) {
 	sort.Slice(stats, func(i, j int) bool {
 		return stats[i].Bitrate > stats[j].Bitrate
 	})
+}
 
-	return stats, iter.Err()
+// packetSort sorts a slice of statEntry objects by their Packets field in descending order.
+//
+// Parameters:
+//
+//	stats []statEntry - the slice of statEntry objects to be sorted
+func packetSort(stats []statEntry) {
+	sort.Slice(stats, func(i, j int) bool {
+		return stats[i].Packets > stats[j].Packets
+	})
+}
+
+// bytesSort sorts a slice of statEntry objects by their Bytes field in descending order.
+//
+// Parameters:
+//
+//	stats []statEntry - the slice of statEntry objects to be sorted
+func bytesSort(stats []statEntry) {
+	sort.Slice(stats, func(i, j int) bool {
+		return stats[i].Bytes > stats[j].Bytes
+	})
+}
+
+// srcIPSort sorts a slice of statEntry objects by their SrcIP field in descending order.
+//
+// Parameters:
+//
+//	stats []statEntry - the slice of statEntry objects to be sorted
+func srcIPSort(stats []statEntry) {
+	sort.Slice(stats, func(i, j int) bool {
+		return stats[i].SrcIP.Compare(stats[j].SrcIP) < 0
+	})
+}
+
+// dstIPSort sorts a slice of statEntry objects by their DstIP field in descending order.
+//
+// Parameters:
+//
+//	stats []statEntry - the slice of statEntry objects to be sorted
+func dstIPSort(stats []statEntry) {
+	sort.Slice(stats, func(i, j int) bool {
+		return stats[i].DstIP.Compare(stats[j].DstIP) < 0
+	})
 }
 
 // formatBitrate formats the bitrate value into a human-readable string.

tui.go

@@ -50,6 +50,7 @@ import (
 // do nothing.
 func drawTUI(objs counterObjects, startTime time.Time) {
 	app := tview.NewApplication()
+	tableSort := bitrateSort
 
 	// packet statistics
 	statsTable := tview.NewTable().
@@ -64,9 +65,25 @@ func drawTUI(objs counterObjects, startTime time.Time) {
 
 	statsTable.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
 		switch event.Rune() {
+		case '0':
+			tableSort = bitrateSort
+			statsTable.Select(0, 0)
+		case '1':
+			tableSort = packetSort
+			statsTable.Select(0, 0)
+		case '2':
+			tableSort = bytesSort
+			statsTable.Select(0, 0)
+		case '3':
+			tableSort = srcIPSort
+			statsTable.Select(0, 0)
+		case '4':
+			tableSort = dstIPSort
+			statsTable.Select(0, 0)
 		case 'q', 'x', 'Q', 'X':
 			app.Stop()
-		case 'r', 'R', 'l', 'L':
+		case 'r', 'R':
+			statsTable.Select(0, 0)
 			app.ForceDraw()
 		}
 
@@ -90,16 +107,16 @@ func drawTUI(objs counterObjects, startTime time.Time) {
 	// navigation
 	naviView := tview.NewTextView().
 		SetTextColor(tcell.ColorYellow)
-	naviView.SetText("Use cursor keys to move through the table. Press 'q' or 'x' to exit. Press 'r' or 'l' for a redraw.")
+	naviView.SetText("Use cursor keys to move through the table. Press 'q' or 'x' to exit, 'r' for a jump to the beginning and a redraw.\nPress '0' for bitrate desc sort, '1' for packet desc sort, '2' for bytes desc sort, '3' for source IP asc sort, '4' for destination IP asc sort.")
 
 	// grid layout
-	grid := tview.NewGrid().SetRows(2, 0, 2).
+	grid := tview.NewGrid().SetRows(2, 0, 3).
 		AddItem(infoView, 0, 0, 1, 1, 0, 0, false).
 		AddItem(statsTable, 1, 0, 1, 1, 0, 0, true).
 		AddItem(naviView, 2, 0, 1, 1, 0, 0, false)
 
 	// start the update loop
-	go updateStatsTable(app, statsTable, objs, startTime)
+	go updateStatsTable(app, statsTable, &tableSort, objs, startTime)
 
 	_ = app.SetRoot(grid, true).
 		SetFocus(statsTable).
@@ -125,7 +142,9 @@ func drawTUI(objs counterObjects, startTime time.Time) {
 //
 // Note that the table is cleared and recreated on each iteration, so any cell
 // attributes are lost on each iteration.
-func updateStatsTable(app *tview.Application, table *tview.Table, objs counterObjects, startTime time.Time) {
+func updateStatsTable(app *tview.Application, table *tview.Table, tableSort *func(stats []statEntry),
+	objs counterObjects, startTime time.Time,
+) {
 	headers := []string{
 		"bitrate", // column 0
 		"packets", // column 1
@@ -153,7 +172,7 @@ func updateStatsTable(app *tview.Application, table *tview.Table, objs counterOb
 			})
 		}
 
-		m, _ := processMap(objs.PktCount, startTime)
+		m, _ := processMap(objs.PktCount, startTime, *tableSort)
 
 		for i, v := range m {
 			// populate bitrate, packets, bytes and proto