added some dhcp4 packet functions and generic byte reading functions

cmd/signal.go

@@ -0,0 +1,69 @@
+package main
+
+import "haza"
+import "sync"
+import "os"
+import "os/signal"
+import "syscall"
+
+type signal_handler struct {
+	svc haza.Service
+}
+
+func (sh *signal_handler) RunTask(wg *sync.WaitGroup) {
+	var sighup_chan  chan os.Signal
+	var sigterm_chan chan os.Signal
+	var sig          os.Signal
+
+	if wg != nil {
+		defer wg.Done()
+	}
+
+	sighup_chan = make(chan os.Signal, 1)
+	sigterm_chan = make(chan os.Signal, 1)
+
+	signal.Notify(sighup_chan, syscall.SIGHUP)
+	signal.Notify(sigterm_chan, syscall.SIGTERM, os.Interrupt)
+
+chan_loop:
+	for {
+		select {
+		case <-sighup_chan:
+			sh.svc.FixServices()
+
+		case sig = <-sigterm_chan:
+			sh.svc.StopServices()
+			sh.svc.WriteLog ("", haza.LOG_INFO, "Received %s signal", sig)
+			break chan_loop
+		}
+	}
+
+	//signal.Reset(syscall.SIGHUP)
+	//signal.Reset(syscall.SIGTERM)
+	signal.Stop(sighup_chan)
+	signal.Stop(sigterm_chan)
+}
+
+func (sh *signal_handler) StartService(data interface{}) {
+	// this isn't actually used standalone..
+	// if we are to implement it, it must use the wait group for signal handler itself
+	// however, this service is run through another service.
+	// sh.wg.Add(1)
+	// go sh.RunTask(&sh.wg)
+}
+
+func (sh *signal_handler) StopServices() {
+	syscall.Kill(syscall.Getpid(), syscall.SIGTERM) // TODO: find a better to terminate the signal handler...
+}
+
+func (sh *signal_handler) FixServices() {
+}
+
+func (sh *signal_handler) WaitForTermination() {
+	// not implemented. see the comment in StartServices()
+	// sh.wg.Wait()
+}
+
+func (sh *signal_handler) WriteLog(id string, level haza.LogLevel, fmt string, args ...interface{}) {
+	sh.svc.WriteLog(id, level, fmt, args...)
+}