From 9e5b93565c8a10f4b06d2bcf61305fdfb7128628 Mon Sep 17 00:00:00 2001
From: John Starks <jostarks@microsoft.com>
Date: Mon, 18 Apr 2016 15:09:55 -0700
Subject: [PATCH] Windows: don't overwrite PID file if process exists
pidfile.New() was opening a file in /proc to determine if the owning
process still exists. Use syscall.OpenProcess() on Windows instead.
Other OSes may also need to be updated here.
Signed-off-by: John Starks <jostarks@microsoft.com>
---
pkg/pidfile/pidfile.go | 3 +--
pkg/pidfile/pidfile_test.go | 8 +++++++-
pkg/pidfile/pidfile_unix.go | 16 ++++++++++++++++
pkg/pidfile/pidfile_windows.go | 23 +++++++++++++++++++++++
4 files changed, 47 insertions(+), 3 deletions(-)
create mode 100644 pkg/pidfile/pidfile_unix.go
create mode 100644 pkg/pidfile/pidfile_windows.go
diff --git a/pkg/pidfile/pidfile.go b/pkg/pidfile/pidfile.go
index 58cc401703..e1ac6bee35 100644
--- a/pkg/pidfile/pidfile.go
+++ b/pkg/pidfile/pidfile.go
@@ -7,7 +7,6 @@ import (
"fmt"
"io/ioutil"
"os"
- "path/filepath"
"strconv"
"strings"
)
@@ -21,7 +20,7 @@ func checkPIDFileAlreadyExists(path string) error {
if pidByte, err := ioutil.ReadFile(path); err == nil {
pidString := strings.TrimSpace(string(pidByte))
if pid, err := strconv.Atoi(pidString); err == nil {
- if _, err := os.Stat(filepath.Join("/proc", strconv.Itoa(pid))); err == nil {
+ if processExists(pid) {
return fmt.Errorf("pid file found, ensure docker is not running or delete %s", path)
}
}
diff --git a/pkg/pidfile/pidfile_test.go b/pkg/pidfile/pidfile_test.go
index d5ef87083b..73e8af76db 100644
--- a/pkg/pidfile/pidfile_test.go
+++ b/pkg/pidfile/pidfile_test.go
@@ -13,11 +13,17 @@ func TestNewAndRemove(t *testing.T) {
t.Fatal("Could not create test directory")
}
- file, err := New(filepath.Join(dir, "testfile"))
+ path := filepath.Join(dir, "testfile")
+ file, err := New(path)
if err != nil {
t.Fatal("Could not create test file", err)
}
+ _, err = New(path)
+ if err == nil {
+ t.Fatal("Test file creation not blocked")
+ }
+
if err := file.Remove(); err != nil {
t.Fatal("Could not delete created test file")
}
diff --git a/pkg/pidfile/pidfile_unix.go b/pkg/pidfile/pidfile_unix.go
new file mode 100644
index 0000000000..28f3deca91
--- /dev/null
+++ b/pkg/pidfile/pidfile_unix.go
@@ -0,0 +1,16 @@
+// +build !windows
+
+package pidfile
+
+import (
+ "os"
+ "path/filepath"
+ "strconv"
+)
+
+func processExists(pid int) bool {
+ if _, err := os.Stat(filepath.Join("/proc", strconv.Itoa(pid))); err == nil {
+ return true
+ }
+ return false
+}
diff --git a/pkg/pidfile/pidfile_windows.go b/pkg/pidfile/pidfile_windows.go
new file mode 100644
index 0000000000..ae489c627a
--- /dev/null
+++ b/pkg/pidfile/pidfile_windows.go
@@ -0,0 +1,23 @@
+package pidfile
+
+import "syscall"
+
+const (
+ processQueryLimitedInformation = 0x1000
+
+ stillActive = 259
+)
+
+func processExists(pid int) bool {
+ h, err := syscall.OpenProcess(processQueryLimitedInformation, false, uint32(pid))
+ if err != nil {
+ return false
+ }
+ var c uint32
+ err = syscall.GetExitCodeProcess(h, &c)
+ syscall.Close(h)
+ if err != nil {
+ return c == stillActive
+ }
+ return true
+}