Implement statistics

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

app/tools/libwg-go/api-android.go

@@ -15,6 +15,7 @@ import (
 	"golang.zx2c4.com/wireguard/device"
 	"golang.zx2c4.com/wireguard/ipc"
 	"golang.zx2c4.com/wireguard/tun"
+	"bytes"
 	"log"
 	"math"
 	"net"
@@ -168,6 +169,22 @@ func wgGetSocketV6(tunnelHandle int32) int32 {
 	return int32(fd)
 }
 
+//export wgGetConfig
+func wgGetConfig(tunnelHandle int32) *C.char {
+	handle, ok := tunnelHandles[tunnelHandle]
+	if !ok {
+		return nil
+	}
+	settings := new(bytes.Buffer)
+	writer := bufio.NewWriter(settings)
+	err := handle.device.IpcGetOperation(writer)
+	if err != nil {
+		return nil
+	}
+	writer.Flush()
+	return C.CString(settings.String())
+}
+
 //export wgVersion
 func wgVersion() *C.char {
 	return C.CString(device.WireGuardGoVersion)