From a172bea54dbd95c86a6d991403b022e70a14b7f2 Mon Sep 17 00:00:00 2001
From: Daniel Theophanes <Daniel Theophanes@localhost>
Date: Fri, 11 May 2012 01:13:06 -0700
Subject: [PATCH] Add Linux Upstart support.

---
 service_linux.go | 123 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)
 create mode 100644 service_linux.go

diff --git a/service_linux.go b/service_linux.go
new file mode 100644
index 0000000..9d3fca0
--- /dev/null
+++ b/service_linux.go
@@ -0,0 +1,123 @@
+package service
+
+import (
+	"os"
+	"fmt"
+	"log/syslog"
+	"text/template"
+	"os/signal"
+)
+
+func newService(name, displayName, description string) (s *linuxUpstartService, err error) {
+	s = &linuxUpstartService{
+		name:        name,
+		displayName: displayName,
+		description: description,
+	}
+
+	s.logger, err = syslog.New(syslog.LOG_INFO, name)
+	if err != nil {
+		return nil, err
+	}
+
+	return s, nil
+}
+
+type linuxUpstartService struct {
+	name, displayName, description string
+	logger                         *syslog.Writer
+}
+
+func (s *linuxUpstartService) Install() error {
+	var confPath = "/etc/init/" + s.name + ".conf"
+	_, err := os.Stat(confPath)
+	if err == nil {
+		return fmt.Errorf("Init already exists: %s", confPath)
+	}
+
+	f, err := os.Create(confPath)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	path, err := getExePath()
+	if err != nil {
+		return err
+	}
+
+	var to = &struct {
+		Display string
+		Description string
+		Path string
+	} {
+		s.displayName,
+		s.description,
+		path,
+	}
+
+	t := template.Must(template.New("upstartScript").Parse(upstartScript))
+	err = t.Execute(f,to)
+
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (s *linuxUpstartService) Remove() error {
+	return os.Remove("/etc/init/" + s.name + ".conf")
+}
+
+func (s *linuxUpstartService) Run(onStart, onStop func() error) error {
+	var err error
+
+	err = onStart()
+	if err != nil {
+		return err
+	}
+
+	var sigChan = make(chan os.Signal, 3)
+
+	signal.Notify(sigChan, os.Kill)
+
+	<- sigChan
+
+	return onStop()
+}
+
+func (s *linuxUpstartService) LogError(format string, a ...interface{}) error {
+	return s.logger.Err(fmt.Sprintf(format, a...))
+}
+func (s *linuxUpstartService) LogWarning(format string, a ...interface{}) error {
+	return s.logger.Warning(fmt.Sprintf(format, a...))
+}
+func (s *linuxUpstartService) LogInfo(format string, a ...interface{}) error {
+	return s.logger.Info(fmt.Sprintf(format, a...))
+}
+
+func getExePath() (exePath string, err error) {
+	return os.Readlink(`/proc/self/exe`)
+}
+
+var upstartScript = `# {{.Description}}
+
+description     "{{.Display}}"
+
+start on filesystem or runlevel [2345]
+stop on runlevel [!2345]
+
+respawn
+respawn limit 10 5
+umask 022
+
+console none
+
+pre-start script
+    test -x {{.Path}} || { stop; exit 0; }
+end script
+
+# Start
+exec {{.Path}}
+`