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

pkg/log/logging.go

@@ -0,0 +1,145 @@
+package log
+
+import (
+	"fmt"
+	golog "log"
+	"os"
+	"strings"
+)
+
+// Level is used to indicate the severity of a log entry
+type Level int
+
+const (
+	// ERROR indicates a significant problem was encountered
+	ERROR Level = iota
+	// WARN indicates something that may be a problem
+	WARN
+	// INFO indicates a purely informational log entry
+	INFO
+	// TRACE entries are meant for development purposes only
+	TRACE
+)
+
+var (
+	// MaxLevel is the highest Level we will log (max TRACE, min ERROR)
+	MaxLevel = TRACE
+
+	// logfname is the name of the logfile
+	logfname string
+
+	// logf is the file we send log output to, will be nil for stderr or stdout
+	logf *os.File
+)
+
+// Initialize logging.  If logfile is equal to "stderr" or "stdout", then
+// we will log to that output stream.  Otherwise the specificed file will
+// opened for writing, and all log data will be placed in it.
+func Initialize(logfile string) error {
+	if logfile != "stderr" {
+		// stderr is the go logging default
+		if logfile == "stdout" {
+			// set to stdout
+			golog.SetOutput(os.Stdout)
+		} else {
+			logfname = logfile
+			if err := openLogFile(); err != nil {
+				return err
+			}
+			// Platform specific
+			closeStdin()
+		}
+	}
+	return nil
+}
+
+// SetLogLevel sets MaxLevel based on the provided string
+func SetLogLevel(level string) (ok bool) {
+	switch strings.ToUpper(level) {
+	case "ERROR":
+		MaxLevel = ERROR
+	case "WARN":
+		MaxLevel = WARN
+	case "INFO":
+		MaxLevel = INFO
+	case "TRACE":
+		MaxLevel = TRACE
+	default:
+		Errorf("Unknown log level requested: " + level)
+		return false
+	}
+	return true
+}
+
+// Errorf logs a message to the 'standard' Logger (always), accepts format strings
+func Errorf(msg string, args ...interface{}) {
+	msg = "[ERROR] " + msg
+	golog.Printf(msg, args...)
+}
+
+// Warnf logs a message to the 'standard' Logger if MaxLevel is >= WARN, accepts format strings
+func Warnf(msg string, args ...interface{}) {
+	if MaxLevel >= WARN {
+		msg = "[WARN ] " + msg
+		golog.Printf(msg, args...)
+	}
+}
+
+// Infof logs a message to the 'standard' Logger if MaxLevel is >= INFO, accepts format strings
+func Infof(msg string, args ...interface{}) {
+	if MaxLevel >= INFO {
+		msg = "[INFO ] " + msg
+		golog.Printf(msg, args...)
+	}
+}
+
+// Tracef logs a message to the 'standard' Logger if MaxLevel is >= TRACE, accepts format strings
+func Tracef(msg string, args ...interface{}) {
+	if MaxLevel >= TRACE {
+		msg = "[TRACE] " + msg
+		golog.Printf(msg, args...)
+	}
+}
+
+// Rotate closes the current log file, then reopens it.  This gives an external
+// log rotation system the opportunity to move the existing log file out of the
+// way and have Inbucket create a new one.
+func Rotate() {
+	// Rotate logs if configured
+	if logf != nil {
+		closeLogFile()
+		// There is nothing we can do if the log open fails
+		_ = openLogFile()
+	} else {
+		Infof("Ignoring SIGHUP, logfile not configured")
+	}
+}
+
+// Close the log file if we have one open
+func Close() {
+	if logf != nil {
+		closeLogFile()
+	}
+}
+
+// openLogFile creates or appends to the logfile passed on commandline
+func openLogFile() error {
+	// use specified log file
+	var err error
+	logf, err = os.OpenFile(logfname, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0666)
+	if err != nil {
+		return fmt.Errorf("Failed to create %v: %v\n", logfname, err)
+	}
+	golog.SetOutput(logf)
+	Tracef("Opened new logfile")
+	// Platform specific
+	reassignStdout()
+	return nil
+}
+
+// closeLogFile closes the current logfile
+func closeLogFile() {
+	Tracef("Closing logfile")
+	// We are never in a situation where we can do anything about failing to close
+	_ = logf.Close()
+}

pkg/log/metrics.go

@@ -0,0 +1,62 @@
+package log
+
+import (
+	"container/list"
+	"expvar"
+	"strings"
+	"time"
+)
+
+// TickerFunc is the type of metrics function accepted by AddTickerFunc
+type TickerFunc func()
+
+var tickerFuncChan = make(chan TickerFunc)
+
+func init() {
+	go metricsTicker()
+}
+
+// AddTickerFunc adds a new function callback to the list of metrics TickerFuncs that get
+// called each minute.
+func AddTickerFunc(f TickerFunc) {
+	tickerFuncChan <- f
+}
+
+// PushMetric adds the metric to the end of the list and returns a comma separated string of the
+// previous 61 entries.  We return 61 instead of 60 (an hour) because the chart on the client
+// tracks deltas between these values - there is nothing to compare the first value against.
+func PushMetric(history *list.List, ev expvar.Var) string {
+	history.PushBack(ev.String())
+	if history.Len() > 61 {
+		history.Remove(history.Front())
+	}
+	return joinStringList(history)
+}
+
+// joinStringList joins a List containing strings by commas
+func joinStringList(listOfStrings *list.List) string {
+	if listOfStrings.Len() == 0 {
+		return ""
+	}
+	s := make([]string, 0, listOfStrings.Len())
+	for e := listOfStrings.Front(); e != nil; e = e.Next() {
+		s = append(s, e.Value.(string))
+	}
+	return strings.Join(s, ",")
+}
+
+func metricsTicker() {
+	funcs := make([]TickerFunc, 0)
+	ticker := time.NewTicker(time.Minute)
+
+	for {
+		select {
+		case <-ticker.C:
+			for _, f := range funcs {
+				f()
+			}
+		case f := <-tickerFuncChan:
+			funcs = append(funcs, f)
+		}
+	}
+}

pkg/log/stdout_unix.go

@@ -0,0 +1,31 @@
+// +build !windows
+
+package log
+
+import (
+	"golang.org/x/sys/unix"
+	"os"
+)
+
+// closeStdin will close stdin on Unix platforms - this is standard practice
+// for daemons
+func closeStdin() {
+	if err := os.Stdin.Close(); err != nil {
+		// Not a fatal error
+		Errorf("Failed to close os.Stdin during log setup")
+	}
+}
+
+// reassignStdout points stdout/stderr to our logfile on systems that support
+// the Dup2 syscall per https://github.com/golang/go/issues/325
+func reassignStdout() {
+	Tracef("Unix reassignStdout()")
+	if err := unix.Dup2(int(logf.Fd()), 1); err != nil {
+		// Not considered fatal
+		Errorf("Failed to re-assign stdout to logfile: %v", err)
+	}
+	if err := unix.Dup2(int(logf.Fd()), 2); err != nil {
+		// Not considered fatal
+		Errorf("Failed to re-assign stderr to logfile: %v", err)
+	}
+}

pkg/log/stdout_windows.go

@@ -0,0 +1,37 @@
+// +build windows
+
+package log
+
+import (
+	"os"
+)
+
+var stdOutsClosed = false
+
+// closeStdin does nothing on Windows, it would always fail
+func closeStdin() {
+	// Nop
+}
+
+// reassignStdout points stdout/stderr to our logfile on systems that do not
+// support the Dup2 syscall
+func reassignStdout() {
+	Tracef("Windows reassignStdout()")
+	if !stdOutsClosed {
+		// Close std* streams to prevent accidental output, they will be redirected to
+		// our logfile below
+
+		// Warning: this will hide panic() output, sorry Windows users
+		if err := os.Stderr.Close(); err != nil {
+			// Not considered fatal
+			Errorf("Failed to close os.Stderr during log setup")
+		}
+		if err := os.Stdin.Close(); err != nil {
+			// Not considered fatal
+			Errorf("Failed to close os.Stdin during log setup")
+		}
+		os.Stdout = logf
+		os.Stderr = logf
+		stdOutsClosed = true
+	}
+}