Merge pull request #582 from ibuildthecloud/fix-symlink

Fix symlinking docker.dist in custom consoles

Godeps/Godeps.json

@@ -363,8 +363,8 @@
 		},
 		{
 			"ImportPath": "github.com/rancher/docker-from-scratch",
-			"Comment": "v1.8.2-1",
+			"Comment": "v1.8.2-1-2-g5852c65",
-			"Rev": "500f0babfdbfcd55fbdbf6690e4508ceb7323474"
+			"Rev": "5852c65f66b6a5e850811dc9782d3b7400531fee"
 		},
 		{
 			"ImportPath": "github.com/rancher/netconf",

Godeps/_workspace/src/github.com/rancher/docker-from-scratch/scratch.go

@@ -23,6 +23,7 @@ const (
 	iptables      = "/sbin/iptables"
 	modprobe      = "/sbin/modprobe"
 	systemdRoot   = "/sys/fs/cgroup/systemd/user.slice"
+	distSuffix    = ".dist"
 )
 
 var (
@@ -189,7 +190,7 @@ func execDocker(config *Config, docker, cmd string, args []string) (*exec.Cmd, e
 		err := cmd.Start()
 		return cmd, err
 	} else {
-		err := syscall.Exec(docker, append([]string{cmd}, args...), env)
+		err := syscall.Exec(expand(docker), append([]string{cmd}, args...), env)
 		return nil, err
 	}
 }
@@ -481,15 +482,27 @@ func setupSystemd(config *Config) error {
 	return ioutil.WriteFile(path.Join(systemdRoot, "cgroup.procs"), []byte(strconv.Itoa(os.Getpid())+"\n"), 0644)
 }
 
+func expand(bin string) string {
+	expanded, err := exec.LookPath(bin)
+	if err == nil {
+		return expanded
+	}
+	return bin
+}
+
 func setupBin(config *Config, bin string) error {
-	if _, err := os.Stat(bin); os.IsNotExist(err) {
+	expanded, err := exec.LookPath(bin)
-		dist := bin + ".dist"
+	if err == nil {
-		if _, err := os.Stat(dist); err == nil {
+		return nil
-			return os.Symlink(dist, bin)
-		}
 	}
 
-	return nil
+	expanded, err = exec.LookPath(bin + distSuffix)
+	if err != nil {
+		// Purposely not returning error
+		return nil
+	}
+
+	return CreateSymlink(expanded, expanded[:len(expanded)-len(distSuffix)])
 }
 
 func setupLogging(config *Config) error {

Makefile.docker

@@ -1,11 +1,12 @@
 include build.conf
 FORCE_PULL := 0
 DEV_BUILD  := 0
+GODEP := godep
 
 
 bin/rancheros:
 	mkdir -p $(dir $@)
-	godep go build -tags netgo -installsuffix netgo -ldflags "-X github.com/rancherio/os/config.VERSION $(VERSION) -linkmode external -extldflags -static" -o $@
+	$(GODEP) go build -tags netgo -installsuffix netgo -ldflags "-X github.com/rancherio/os/config.VERSION $(VERSION) -linkmode external -extldflags -static" -o $@
 	strip --strip-all $@
 
 

cmd/userdocker/main.go

@@ -72,26 +72,23 @@ type result struct {
 	Pid int `json:"Pid"`
 }
 
-func expand(first, second string, args []string) ([]string, error) {
+func findProgram(searchPaths ...string) string {
-	var err error
 	prog := ""
 
-	prog, err = exec.LookPath(first)
+	for _, i := range searchPaths {
-	if err != nil {
+		var err error
-		prog, err = exec.LookPath(second)
+		prog, err = exec.LookPath(i)
-	}
+		if err == nil {
-	if err != nil {
+			break
-		return nil, err
+		}
+		prog = i
 	}
 
-	return append([]string{prog}, args...), nil
+	return prog
 }
 
 func runNsenter(pid int) error {
-	args, err := expand(userDocker, "", []string{"main"})
+	args := []string{findProgram(userDocker), "main"}
-	if err != nil {
-		return err
-	}
 
 	r, w, err := os.Pipe()
 	if err != nil {
@@ -227,14 +224,15 @@ func main(cfg *config.CloudConfig) error {
 		}
 	}
 
-	args, err := expand("docker-init", "docker", args)
+	prog := findProgram("docker-init", "dockerlaunch", "docker")
-	if err != nil {
+	if strings.Contains(prog, "dockerlaunch") {
-		return err
+		args = append([]string{prog, "docker"}, args...)
+	} else {
+		args = append([]string{prog}, args...)
 	}
 
 	log.Infof("Running %v", args)
-	err = syscall.Exec(args[0], args, dockerCfg.AppendEnv())
+	return syscall.Exec(args[0], args, dockerCfg.AppendEnv())
-	return err
 }
 
 func switchCgroup(src, target int) error {