Reorganize packages, closes #79

- All packages go into either cmd or pkg directories
- Most packages renamed
- Server packages moved into pkg/server
- sanitize moved into webui, as that's the only place it's used
- filestore moved into pkg/storage/file
- Makefile updated, and PKG variable use fixed

cmd/inbucket/main.go

@@ -0,0 +1,183 @@
+// main is the inbucket daemon launcher
+package main
+
+import (
+	"context"
+	"expvar"
+	"flag"
+	"fmt"
+	"os"
+	"os/signal"
+	"runtime"
+	"syscall"
+	"time"
+
+	"github.com/jhillyerd/inbucket/pkg/config"
+	"github.com/jhillyerd/inbucket/pkg/log"
+	"github.com/jhillyerd/inbucket/pkg/msghub"
+	"github.com/jhillyerd/inbucket/pkg/rest"
+	"github.com/jhillyerd/inbucket/pkg/server/pop3"
+	"github.com/jhillyerd/inbucket/pkg/server/smtp"
+	"github.com/jhillyerd/inbucket/pkg/server/web"
+	"github.com/jhillyerd/inbucket/pkg/storage/file"
+	"github.com/jhillyerd/inbucket/pkg/webui"
+)
+
+var (
+	// version contains the build version number, populated during linking
+	version = "undefined"
+
+	// date contains the build date, populated during linking
+	date = "undefined"
+
+	// Command line flags
+	help    = flag.Bool("help", false, "Displays this help")
+	pidfile = flag.String("pidfile", "none", "Write our PID into the specified file")
+	logfile = flag.String("logfile", "stderr", "Write out log into the specified file")
+
+	// shutdownChan - close it to tell Inbucket to shut down cleanly
+	shutdownChan = make(chan bool)
+
+	// Server instances
+	smtpServer *smtp.Server
+	pop3Server *pop3.Server
+)
+
+func init() {
+	flag.Usage = func() {
+		fmt.Fprintln(os.Stderr, "Usage of inbucket [options] <conf file>:")
+		flag.PrintDefaults()
+	}
+
+	// Server uptime for status page
+	startTime := time.Now()
+	expvar.Publish("uptime", expvar.Func(func() interface{} {
+		return time.Since(startTime) / time.Second
+	}))
+
+	// Goroutine count for status page
+	expvar.Publish("goroutines", expvar.Func(func() interface{} {
+		return runtime.NumGoroutine()
+	}))
+}
+
+func main() {
+	config.Version = version
+	config.BuildDate = date
+
+	flag.Parse()
+	if *help {
+		flag.Usage()
+		return
+	}
+
+	// Root context
+	rootCtx, rootCancel := context.WithCancel(context.Background())
+
+	// Load & Parse config
+	if flag.NArg() != 1 {
+		flag.Usage()
+		os.Exit(1)
+	}
+	err := config.LoadConfig(flag.Arg(0))
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to parse config: %v\n", err)
+		os.Exit(1)
+	}
+
+	// Setup signal handler
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, syscall.SIGHUP, syscall.SIGTERM, syscall.SIGINT)
+
+	// Initialize logging
+	log.SetLogLevel(config.GetLogLevel())
+	if err := log.Initialize(*logfile); err != nil {
+		fmt.Fprintf(os.Stderr, "%v", err)
+		os.Exit(1)
+	}
+	defer log.Close()
+
+	log.Infof("Inbucket %v (%v) starting...", config.Version, config.BuildDate)
+
+	// Write pidfile if requested
+	if *pidfile != "none" {
+		pidf, err := os.Create(*pidfile)
+		if err != nil {
+			log.Errorf("Failed to create %q: %v", *pidfile, err)
+			os.Exit(1)
+		}
+		fmt.Fprintf(pidf, "%v\n", os.Getpid())
+		if err := pidf.Close(); err != nil {
+			log.Errorf("Failed to close PID file %q: %v", *pidfile, err)
+		}
+	}
+
+	// Create message hub
+	msgHub := msghub.New(rootCtx, config.GetWebConfig().MonitorHistory)
+
+	// Grab our datastore
+	ds := filestore.DefaultFileDataStore()
+
+	// Start HTTP server
+	web.Initialize(config.GetWebConfig(), shutdownChan, ds, msgHub)
+	webui.SetupRoutes(web.Router)
+	rest.SetupRoutes(web.Router)
+	go web.Start(rootCtx)
+
+	// Start POP3 server
+	pop3Server = pop3.New(config.GetPOP3Config(), shutdownChan, ds)
+	go pop3Server.Start(rootCtx)
+
+	// Startup SMTP server
+	smtpServer = smtp.NewServer(config.GetSMTPConfig(), shutdownChan, ds, msgHub)
+	go smtpServer.Start(rootCtx)
+
+	// Loop forever waiting for signals or shutdown channel
+signalLoop:
+	for {
+		select {
+		case sig := <-sigChan:
+			switch sig {
+			case syscall.SIGHUP:
+				log.Infof("Recieved SIGHUP, cycling logfile")
+				log.Rotate()
+			case syscall.SIGINT:
+				// Shutdown requested
+				log.Infof("Received SIGINT, shutting down")
+				close(shutdownChan)
+			case syscall.SIGTERM:
+				// Shutdown requested
+				log.Infof("Received SIGTERM, shutting down")
+				close(shutdownChan)
+			}
+		case <-shutdownChan:
+			rootCancel()
+			break signalLoop
+		}
+	}
+
+	// Wait for active connections to finish
+	go timedExit()
+	smtpServer.Drain()
+	pop3Server.Drain()
+
+	removePIDFile()
+}
+
+// removePIDFile removes the PID file if created
+func removePIDFile() {
+	if *pidfile != "none" {
+		if err := os.Remove(*pidfile); err != nil {
+			log.Errorf("Failed to remove %q: %v", *pidfile, err)
+		}
+	}
+}
+
+// timedExit is called as a goroutine during shutdown, it will force an exit
+// after 15 seconds
+func timedExit() {
+	time.Sleep(15 * time.Second)
+	log.Errorf("Clean shutdown took too long, forcing exit")
+	removePIDFile()
+	os.Exit(0)
+}