1 files changed, 85 insertions, 0 deletions
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..fc6c8af
--- /dev/null
+++ b/main.go
@@ -0,0 +1,85 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"net"
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+type Flags struct {
+	Groups   string
+	HostName string
+	Listen   string
+	StdErr   string
+}
+
+func ParseArgs() (*Flags, []string) {
+	var flags Flags
+
+	name, _ := os.Hostname()
+
+	flag.StringVar(&flags.Groups, "groups", "/etc/postfix/user_groups", "User group list")
+	flag.StringVar(&flags.HostName, "hostname", name, "E-Mail hostname")
+	flag.StringVar(&flags.Listen, "listen", "-", "listen socket path")
+	flag.StringVar(&flags.StdErr, "std-err", name, "Redirect errors to filepath")
+
+	flag.Parse()
+
+	return &flags, flag.Args()
+}
+
+func handleSignal(c <-chan os.Signal, listenner net.Listener) {
+	for v := range c {
+		switch v {
+		case syscall.SIGINT:
+			_ = listenner.Close()
+		default:
+		}
+	}
+}
+
+func exitOnErr(err error) {
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err.Error())
+		os.Exit(1)
+	}
+}
+
+func main() {
+	flags, groups := ParseArgs()
+
+	if flags.StdErr != "" {
+		f, _ := os.OpenFile(flags.StdErr, os.O_APPEND|os.O_RDWR|os.O_CREATE, 0666)
+		os.Stderr = f
+		defer f.Close()
+	}
+
+	srv := &Server{
+		HostName:   flags.HostName,
+		GroupsFile: flags.Groups,
+		Groups:     groups,
+	}
+
+	if flags.Listen == "-" {
+		srv.HandleConn(os.Stdout, os.Stdin)
+
+		return
+	}
+
+	listenner, err := net.Listen("unix", flags.Listen)
+	exitOnErr(err)
+	defer os.Remove(flags.Listen)
+
+	err = os.Chmod(flags.Listen, os.ModePerm)
+	exitOnErr(err)
+
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, syscall.SIGHUP, syscall.SIGINT)
+	go handleSignal(c, listenner)
+
+	err = ServeUnixSocket(listenner, srv)
+	exitOnErr(err)
+}