add syslog driver

Signed-off-by: wlan0 <sid@rancher.com>

daemon/config.go

@@ -83,7 +83,7 @@ func (config *Config) InstallFlags() {
 	opts.LabelListVar(&config.Labels, []string{"-label"}, "Set key=value labels to the daemon")
 	config.Ulimits = make(map[string]*ulimit.Ulimit)
 	opts.UlimitMapVar(config.Ulimits, []string{"-default-ulimit"}, "Set default ulimits for containers")
-	flag.StringVar(&config.LogConfig.Type, []string{"-log-driver"}, "json-file", "Containers logging driver(json-file/none)")
+	flag.StringVar(&config.LogConfig.Type, []string{"-log-driver"}, "json-file", "Containers logging driver")
 }
 
 func getDefaultNetworkMtu() int {

daemon/container.go

@@ -23,6 +23,7 @@ import (
 	"github.com/docker/docker/daemon/execdriver"
 	"github.com/docker/docker/daemon/logger"
 	"github.com/docker/docker/daemon/logger/jsonfilelog"
+	"github.com/docker/docker/daemon/logger/syslog"
 	"github.com/docker/docker/engine"
 	"github.com/docker/docker/image"
 	"github.com/docker/docker/links"
@@ -1377,6 +1378,12 @@ func (container *Container) startLogging() error {
 			return err
 		}
 		l = dl
+	case "syslog":
+		dl, err := syslog.New(container.ID[:12])
+		if err != nil {
+			return err
+		}
+		l = dl
 	case "none":
 		return nil
 	default:

daemon/logger/syslog/syslog.go

@@ -0,0 +1,54 @@
+package syslog
+
+import (
+	"fmt"
+	"log/syslog"
+	"os"
+	"path"
+	"sync"
+
+	"github.com/docker/docker/daemon/logger"
+)
+
+type Syslog struct {
+	writer *syslog.Writer
+	tag    string
+	mu     sync.Mutex
+}
+
+func New(tag string) (logger.Logger, error) {
+	log, err := syslog.New(syslog.LOG_USER, path.Base(os.Args[0]))
+	if err != nil {
+		return nil, err
+	}
+	return &Syslog{
+		writer: log,
+		tag:    tag,
+	}, nil
+}
+
+func (s *Syslog) Log(msg *logger.Message) error {
+	logMessage := fmt.Sprintf("%s: %s", s.tag, string(msg.Line))
+	if msg.Source == "stderr" {
+		if err := s.writer.Err(logMessage); err != nil {
+			return err
+		}
+
+	} else {
+		if err := s.writer.Info(logMessage); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *Syslog) Close() error {
+	if s.writer != nil {
+		return s.writer.Close()
+	}
+	return nil
+}
+
+func (s *Syslog) Name() string {
+	return "Syslog"
+}