From 57450191691186ab3dd0c6aa5c9bc18e81988eb5 Mon Sep 17 00:00:00 2001
From: volpol <volpol@packet-gain.de>
Date: Sat, 9 Jun 2018 21:07:44 +0200
Subject: [PATCH] Support cmdline switches

---
 ddnset.go | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/ddnset.go b/ddnset.go
index 97d9cd5..416a9a7 100644
--- a/ddnset.go
+++ b/ddnset.go
@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"crypto/md5"
 	"encoding/base64"
+	"flag"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -15,14 +16,20 @@ import (
 	"strings"
 )
 
-//TODO add parsing of cmdline
 const (
-	AccFile    = "/usr/local/etc/ddnset/ddnset.acc"
-	ZoneFile   = "/usr/local/etc/ddnset/ddnset.zon"
-	Logfile    = "/var/log/ddnset/default.log"
-	ListenPort = "1980"
+	DefaultAccFile    = "/usr/local/etc/ddnset/ddnset.acc"
+	DefaultZoneFile   = "/usr/local/etc/ddnset/ddnset.zon"
+	DefaultLogFile    = "/var/log/ddnset/default.log"
+	DefaultListenPort = 1980
 )
 
+var AccFile = flag.String("a", DefaultAccFile, "Path to account file")
+var ZoneFile = flag.String("z", DefaultZoneFile, "Path to zone file")
+var LogFile = flag.String("l", DefaultLogFile, "Path to log file")
+var ListenPort = flag.Uint("p", DefaultListenPort, "Port to listen on")
+
+var Help = flag.Bool("h", false, "Show usage")
+
 const (
 	StatusGood    = "good"
 	StatusBadAuth = "badauth"
@@ -116,7 +123,7 @@ func checkIP(s string) (string, int, bool) {
 
 func isValidAuth(usr, psw string) (bool, string) {
 	pwentry := fmt.Sprintf("%s:%x", usr, md5.Sum([]byte(psw)))
-	acc, err := os.Open(AccFile)
+	acc, err := os.Open(*AccFile)
 	if nil == err {
 		defer acc.Close()
 		scanner := bufio.NewScanner(acc)
@@ -133,7 +140,7 @@ func isValidAuth(usr, psw string) (bool, string) {
 }
 
 func isValidZone(h string) (bool, string) {
-	zon, err := os.Open(ZoneFile)
+	zon, err := os.Open(*ZoneFile)
 	if nil == err {
 		defer zon.Close()
 		scanner := bufio.NewScanner(zon)
@@ -272,10 +279,18 @@ func rootHandle(w http.ResponseWriter, r *http.Request) {
 }
 
 func main() {
+	flag.Parse()
+	if *Help {
+		fmt.Printf("Usage: \n")
+		flag.PrintDefaults()
+		return
+	}
+	fmt.Printf("Current settings: \n")
+	flag.VisitAll(func(f *flag.Flag) { fmt.Printf("%v: %v\n", f.Usage, f.Value) })
 	http.HandleFunc("/myip", myipHandle)
 	http.HandleFunc("/myip.php", myipHandle)
 	http.HandleFunc("/", rootHandle)
-	logf, err := os.OpenFile(Logfile, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
+	logf, err := os.OpenFile(*LogFile, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
 	if nil == err {
 		defer logf.Close()
 		log.SetOutput(logf)
@@ -283,5 +298,5 @@ func main() {
 		log.Print(err)
 	}
 
-	log.Fatal(http.ListenAndServe(":"+ListenPort, nil))
+	log.Fatal(http.ListenAndServe(fmt.Sprintf(":%d", *ListenPort), nil))
 }
-- 
2.30.2