add syslog log destination (#83)

conf.go

@@ -160,6 +160,9 @@ func loadConf(fpath string, stdin io.Reader) (*conf, error) {
 		case "file":
 			conf.logDestinationsParsed[logDestinationFile] = struct{}{}
 
+		case "syslog":
+			conf.logDestinationsParsed[logDestinationSyslog] = struct{}{}
+
 		default:
 			return nil, fmt.Errorf("unsupported log destination: %s", dest)
 		}

log-syslog_unix.go

@@ -0,0 +1,30 @@
+// +build !windows
+
+package main
+
+import (
+	"log/syslog"
+)
+
+type logSyslog struct {
+	inner *syslog.Writer
+}
+
+func newLogSyslog() (*logSyslog, error) {
+	inner, err := syslog.New(syslog.LOG_INFO|syslog.LOG_DAEMON, "rtsp-simple-server")
+	if err != nil {
+		return nil, err
+	}
+
+	return &logSyslog{
+		inner: inner,
+	}, nil
+}
+
+func (ls *logSyslog) close() {
+	ls.inner.Close()
+}
+
+func (ls *logSyslog) write(p []byte) (int, error) {
+	return ls.inner.Write(p)
+}

log-syslog_win.go

@@ -0,0 +1,21 @@
+// +build windows
+
+package main
+
+import (
+	"fmt"
+)
+
+type logSyslog struct {
+}
+
+func newLogSyslog() (*logSyslog, error) {
+	return nil, fmt.Errorf("not implemented on windows")
+}
+
+func (ls *logSyslog) close() {
+}
+
+func (ls *logSyslog) write(p []byte) (int, error) {
+	return 0, nil
+}

log.go

@@ -10,22 +10,34 @@ type logDestination int
 const (
 	logDestinationStdout logDestination = iota
 	logDestinationFile
+	logDestinationSyslog
 )
 
 type logHandler struct {
-	logDestinationsParsed map[logDestination]struct{}
-	logFile               *os.File
+	logDestinations map[logDestination]struct{}
+	logFile         *os.File
+	logSyslog       *logSyslog
 }
 
-func newLogHandler(logDestinationsParsed map[logDestination]struct{}, logFilePath string) (*logHandler, error) {
+func newLogHandler(logDestinations map[logDestination]struct{}, logFilePath string) (*logHandler, error) {
 	lh := &logHandler{
-		logDestinationsParsed: logDestinationsParsed,
+		logDestinations: logDestinations,
 	}
 
-	if _, ok := logDestinationsParsed[logDestinationFile]; ok {
+	if _, ok := logDestinations[logDestinationFile]; ok {
 		var err error
 		lh.logFile, err = os.OpenFile(logFilePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
 		if err != nil {
+			lh.close()
+			return nil, err
+		}
+	}
+
+	if _, ok := logDestinations[logDestinationSyslog]; ok {
+		var err error
+		lh.logSyslog, err = newLogSyslog()
+		if err != nil {
+			lh.close()
 			return nil, err
 		}
 	}
@@ -35,22 +47,28 @@ func newLogHandler(logDestinationsParsed map[logDestination]struct{}, logFilePat
 	return lh, nil
 }
 
-func (lh *logHandler) close() error {
+func (lh *logHandler) close() {
 	if lh.logFile != nil {
 		lh.logFile.Close()
 	}
 
-	return nil
+	if lh.logSyslog != nil {
+		lh.logSyslog.close()
+	}
 }
 
 func (lh *logHandler) Write(p []byte) (int, error) {
-	if _, ok := lh.logDestinationsParsed[logDestinationStdout]; ok {
+	if _, ok := lh.logDestinations[logDestinationStdout]; ok {
 		print(string(p))
 	}
 
-	if _, ok := lh.logDestinationsParsed[logDestinationFile]; ok {
+	if _, ok := lh.logDestinations[logDestinationFile]; ok {
 		lh.logFile.Write(p)
 	}
 
+	if _, ok := lh.logDestinations[logDestinationSyslog]; ok {
+		lh.logSyslog.write(p)
+	}
+
 	return len(p), nil
 }

rtsp-simple-server.yml

@@ -24,7 +24,7 @@ runOnConnect:
 metrics: no
 # enable pprof on port 9999 to monitor performances
 pprof: no
-# destinations of log messages; available options are 'stdout' and 'file'
+# destinations of log messages; available options are 'stdout', 'file' and 'syslog'
 logDestinations: [stdout]
 # if 'file' is in logDestinations, this is the file that will receive the logs
 logFile: rtsp-simple-server.log