Refactor debug.go

debug/debug.go

@@ -14,28 +14,31 @@ import (
 )
 
 var opts struct {
+	logger *log.Logger
 	tags   map[string]bool
 	breaks map[string]bool
 	m      sync.Mutex
 }
 
-var debugLogger = initDebugLogger()
+func init() {
-
+	initDebugLogger()
-func initDebugLogger() (lgr *log.Logger) {
+	initDebugTags()
-	opts.tags = make(map[string]bool)
+	initDebugBreaks()
-	opts.breaks = make(map[string]bool)
 
 	fmt.Fprintf(os.Stderr, "debug enabled\n")
+}
 
+func initDebugLogger() {
 	debugfile := os.Getenv("DEBUG_LOG")
-	if debugfile != "" {
+	if debugfile == "" {
+		return
+	}
+
 	fmt.Fprintf(os.Stderr, "debug log file %v\n", debugfile)
 
-		// open logfile
 	f, err := os.OpenFile(debugfile, os.O_WRONLY|os.O_APPEND, 0600)
 
 	if err == nil {
-			// seek to the end
 		_, err = f.Seek(2, 0)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "unable to seek to the end of %v: %v\n", debugfile, err)
@@ -44,7 +47,6 @@ func initDebugLogger() (lgr *log.Logger) {
 	}
 
 	if err != nil && os.IsNotExist(err) {
-			// create logfile
 		f, err = os.OpenFile(debugfile, os.O_WRONLY|os.O_CREATE, 0600)
 	}
 
@@ -53,16 +55,21 @@ func initDebugLogger() (lgr *log.Logger) {
 		os.Exit(2)
 	}
 
-		// open logger
+	opts.logger = log.New(f, "", log.LstdFlags)
-		lgr = log.New(f, "", log.LstdFlags)
+}
-	}
+
+func initDebugTags() {
+	opts.tags = make(map[string]bool)
 
 	// defaults
 	opts.tags["break"] = true
 
 	// initialize tags
 	env := os.Getenv("DEBUG_TAGS")
-	if len(env) > 0 {
+	if len(env) == 0 {
+		return
+	}
+
 	tags := []string{}
 
 	for _, tag := range strings.Split(env, ",") {
@@ -88,11 +95,16 @@ func initDebugLogger() (lgr *log.Logger) {
 	}
 
 	fmt.Fprintf(os.Stderr, "debug log enabled for: %v\n", tags)
+}
+
+func initDebugBreaks() {
+	opts.breaks = make(map[string]bool)
+
+	env := os.Getenv("DEBUG_BREAK")
+	if len(env) == 0 {
+		return
 	}
 
-	// initialize break tags
-	env = os.Getenv("DEBUG_BREAK")
-	if len(env) > 0 {
 	breaks := []string{}
 
 	for _, tag := range strings.Split(env, ",") {
@@ -102,13 +114,9 @@ func initDebugLogger() (lgr *log.Logger) {
 	}
 
 	fmt.Fprintf(os.Stderr, "debug breaks enabled for: %v\n", breaks)
-	}
-
-	return
 }
 
 func Log(tag string, f string, args ...interface{}) {
-	// synchronize log writes
 	opts.m.Lock()
 	defer opts.m.Unlock()
 
@@ -120,8 +128,8 @@ func Log(tag string, f string, args ...interface{}) {
 		fmt.Fprintf(os.Stderr, "DEBUG["+tag+"]: "+f, args...)
 	}
 
-	if debugLogger != nil {
+	if opts.logger != nil {
-		debugLogger.Printf("["+tag+"] "+f, args...)
+		opts.logger.Printf("["+tag+"] "+f, args...)
 	}
 
 	// check if tag is enabled directly