From 4e20111ff66c4c303280d287dc1688d63976ae36 Mon Sep 17 00:00:00 2001
From: Mikkel Krautz <mikkel@krautz.dk>
Date: Mon, 16 May 2011 23:32:41 +0200
Subject: [PATCH] Windows support for blobstore

---
 pkg/blobstore/Makefile       |  6 ++++++
 pkg/blobstore/blobstore.go   |  7 +++----
 pkg/blobstore/pid_unix.go    | 17 +++++++++++++++++
 pkg/blobstore/pid_windows.go | 20 ++++++++++++++++++++
 4 files changed, 46 insertions(+), 4 deletions(-)
 create mode 100644 pkg/blobstore/pid_unix.go
 create mode 100644 pkg/blobstore/pid_windows.go

diff --git a/pkg/blobstore/Makefile b/pkg/blobstore/Makefile
index 5bf0f89..db07d2f 100644
--- a/pkg/blobstore/Makefile
+++ b/pkg/blobstore/Makefile
@@ -5,4 +5,10 @@ GOFILES = \
 	blobstore.go \
 	blobreader.go
 
+ifeq ($(GOOS),windows)
+GOFILES += pid_windows.go
+else
+GOFILES += pid_unix.go
+endif
+
 include $(GOROOT)/src/Make.pkg
diff --git a/pkg/blobstore/blobstore.go b/pkg/blobstore/blobstore.go
index 0b914cd..186c15d 100644
--- a/pkg/blobstore/blobstore.go
+++ b/pkg/blobstore/blobstore.go
@@ -186,10 +186,9 @@ func acquireLockfile(path string) os.Error {
 			return err
 		}
 
-		pid, err := strconv.Atoi(string(content))
+		pid, err := strconv.Atoui64(string(content))
 		if err == nil {
-			errno := syscall.Kill(pid, 0)
-			if errno == 0 {
+			if pidRunning(pid) {
 				return ErrLocked
 			}
 		}
@@ -220,7 +219,7 @@ func acquireLockfile(path string) os.Error {
 	} else if err != nil {
 		return err
 	} else {
-		_, err = lockfile.WriteString(strconv.Itoa(syscall.Getpid()))
+		_, err = lockfile.WriteString(strconv.Uitoa64(getPid()))
 		if err != nil {
 			return err
 		}
diff --git a/pkg/blobstore/pid_unix.go b/pkg/blobstore/pid_unix.go
new file mode 100644
index 0000000..a4fcc53
--- /dev/null
+++ b/pkg/blobstore/pid_unix.go
@@ -0,0 +1,17 @@
+// Copyright (c) 2011 The Grumble Authors
+// The use of this source code is goverened by a BSD-style
+// license that can be found in the LICENSE-file.
+
+package blobstore
+
+import (
+	"syscall"
+)
+
+func getPid() uint64 {
+	return uint64(syscall.Getpid())
+}
+
+func pidRunning(pid uint64) bool {
+	return syscall.Kill(int(pid), 0) == 0
+}
diff --git a/pkg/blobstore/pid_windows.go b/pkg/blobstore/pid_windows.go
new file mode 100644
index 0000000..043010f
--- /dev/null
+++ b/pkg/blobstore/pid_windows.go
@@ -0,0 +1,20 @@
+// Copyright (c) 2011 The Grumble Authors
+// The use of this source code is goverened by a BSD-style
+// license that can be found in the LICENSE-file.
+
+package blobstore
+
+import (
+	"syscall"
+)
+
+func getPid() uint64 {
+	handle, _ := syscall.GetCurrentProcess()
+	return uint64(handle)
+}
+
+func pidRunning(pid uint64) bool {
+	var status uint32
+	syscall.GetExitCodeProcess(uint32(pid), &status)
+	return status == 259 // STILL_ACTIVE 
+}