Address initial feedback from pr

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)

docker/docker.go

@@ -17,7 +17,7 @@ import (
 )
 
 func main() {
-	if selfPath := utils.SelfPath(); selfPath == "/sbin/init" || strings.Contains(selfPath, ".dockerinit") {
+	if selfPath := utils.SelfPath(); strings.Contains(selfPath, ".dockerinit") {
 		// Running in init mode
 		sysinit.SysInit()
 		return

execdriver/native/driver.go

@@ -2,7 +2,6 @@ package native
 
 import (
 	"encoding/json"
-	"errors"
 	"fmt"
 	"github.com/dotcloud/docker/execdriver"
 	"github.com/dotcloud/docker/pkg/cgroups"
@@ -22,10 +21,6 @@ const (
 	Version    = "0.1"
 )
 
-var (
-	ErrNotSupported = errors.New("not supported")
-)
-
 func init() {
 	execdriver.RegisterInitFunc(DriverName, func(args *execdriver.InitArgs) error {
 		var (
@@ -109,10 +104,13 @@ func (d *driver) Restore(c *execdriver.Command) error {
 	if err != nil {
 		return err
 	}
-	defer f.Close()
 	if _, err := fmt.Fscanf(f, "%d", &nspid); err != nil {
+		f.Close()
 		return err
 	}
+	f.Close()
+	defer os.Remove(p)
+
 	proc, err := os.FindProcess(nspid)
 	if err != nil {
 		return err

integration/runtime_test.go

@@ -85,7 +85,7 @@ func init() {
 	os.Setenv("TEST", "1")
 
 	// Hack to run sys init during unit testing
-	if selfPath := utils.SelfPath(); selfPath == "/sbin/init" || strings.Contains(selfPath, ".dockerinit") {
+	if selfPath := utils.SelfPath(); strings.Contains(selfPath, ".dockerinit") {
 		sysinit.SysInit()
 		return
 	}

pkg/system/setns_linux.go

@@ -1,11 +1,30 @@
 package system
 
 import (
+	"errors"
+	"fmt"
+	"runtime"
 	"syscall"
 )
 
+var (
+	ErrNotSupportedPlatform = errors.New("platform and architecture is not supported")
+)
+
+// Via http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7b21fddd087678a70ad64afc0f632e0f1071b092
+//
+// We need different setns values for the different platforms and arch
+// We are declaring the macro here because the SETNS syscall does not exist in th stdlib
+var setNsMap = map[string]uintptr{
+	"linux/amd64": 308,
+}
+
 func Setns(fd uintptr, flags uintptr) error {
-	_, _, err := syscall.RawSyscall(SYS_SETNS, fd, flags, 0)
+	ns, exists := setNsMap[fmt.Sprintf("%s/%s", runtime.GOOS, runtime.GOARCH)]
+	if !exists {
+		return ErrNotSupportedPlatform
+	}
+	_, _, err := syscall.RawSyscall(ns, fd, flags, 0)
 	if err != 0 {
 		return err
 	}

pkg/system/setns_linux_amd64.go

@@ -1,8 +0,0 @@
-// +build linux,amd64
-
-package system
-
-// Via http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7b21fddd087678a70ad64afc0f632e0f1071b092
-const (
-	SYS_SETNS = 308
-)