Make easier for daemonization

- Create pidfile if requested
- Create logfile and close std* streams if requested

.gitignore

@@ -24,5 +24,5 @@ _testmain.go
 # vim swp files
 *.swp
 
-# revel tmp
-app/tmp
+# our binary
+/inbucket

inbucket.go

@@ -11,11 +11,14 @@ import (
 	"github.com/jhillyerd/inbucket/log"
 	"github.com/jhillyerd/inbucket/smtpd"
 	"github.com/jhillyerd/inbucket/web"
+	golog "log"
 	"os"
 	"time"
 )
 
 var help = flag.Bool("help", false, "Displays this help")
+var pidfile = flag.String("pidfile", "none", "Write our PID into the specified file")
+var logfile = flag.String("logfile", "stderr", "Write out log into the specified file")
 
 var startTime = time.Now()
 
@@ -37,10 +40,46 @@ func main() {
 		os.Exit(1)
 	}
 
-	// Configure logging
+	// Configure logging, close std* fds
+	if *logfile != "stderr" {
+		// stderr is the go logging default
+		if *logfile == "stdout" {
+			// set to stdout
+			golog.SetOutput(os.Stdout)
+		} else {
+			// use specificed log file
+			logf, err := os.OpenFile(*logfile, os.O_WRONLY | os.O_APPEND | os.O_CREATE, 0666)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "Failed to create %v: %v\n", *logfile, err)
+				os.Exit(1)
+			}
+			defer logf.Close()
+			golog.SetOutput(logf)
+
+			// close std* streams
+			os.Stdout.Close()
+			os.Stderr.Close()
+			os.Stdin.Close()
+			os.Stdout = logf
+			os.Stderr = logf
+		}
+	}
+
 	level, _ := config.Config.String("logging", "level")
 	log.SetLogLevel(level)
 
+	// Write pidfile if requested
+	// TODO: Probably supposed to remove pidfile during shutdown
+	if *pidfile != "none" {
+		pidf, err := os.Create(*pidfile)
+		if err != nil {
+			log.Error("Failed to create %v: %v", *pidfile, err)
+			os.Exit(1)
+		}
+		defer pidf.Close()
+		fmt.Fprintf(pidf, "%v\n", os.Getpid())
+	}
+
 	// Startup SMTP server
 	server := smtpd.New()
 	go server.Start()