Added ScopedPrinterHandle

TEST=it compiles
BUG=none

Review URL: http://codereview.chromium.org/9480026

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@124640 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 35 insertions, 16 deletions

diff --git a/base/win/scoped_handle.h b/base/win/scoped_handle.h
index 3bb0279..44e723f 100644
--- a/base/win/scoped_handle.h
+++ b/base/win/scoped_handle.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -30,16 +30,17 @@ namespace win {
 //
 // To explicitly close the handle:
 //   hfile.Close();
-class ScopedHandle {
+template <class Traits>
+class GenericScopedHandle {
  public:
-  ScopedHandle() : handle_(NULL) {
+  GenericScopedHandle() : handle_(NULL) {
   }
 
-  explicit ScopedHandle(HANDLE h) : handle_(NULL) {
+  explicit GenericScopedHandle(HANDLE h) : handle_(NULL) {
     Set(h);
   }
 
-  ~ScopedHandle() {
+  ~GenericScopedHandle() {
     Close();
   }
 
@@ -63,6 +64,11 @@ class ScopedHandle {
 
   operator HANDLE() { return handle_; }
 
+  HANDLE* Receive() {
+    DCHECK(!handle_) << "Handle must be NULL";
+    return &handle_;
+  }
+
   HANDLE Take() {
     // transfers ownership away from this object
     HANDLE h = handle_;
@@ -72,7 +78,7 @@ class ScopedHandle {
 
   void Close() {
     if (handle_) {
-      if (!::CloseHandle(handle_)) {
+      if (!Traits::CloseHandle(handle_)) {
         NOTREACHED();
       }
       handle_ = NULL;
@@ -81,9 +87,18 @@ class ScopedHandle {
 
  private:
   HANDLE handle_;
-  DISALLOW_COPY_AND_ASSIGN(ScopedHandle);
+  DISALLOW_COPY_AND_ASSIGN(GenericScopedHandle);
 };
 
+class HandleTraits {
+ public:
+  static bool CloseHandle(HANDLE handle) {
+    return ::CloseHandle(handle) != FALSE;
+  }
+};
+
+typedef GenericScopedHandle<HandleTraits> ScopedHandle;
+
 }  // namespace win
 }  // namespace base
 
diff --git a/printing/backend/win_helper.h b/printing/backend/win_helper.h
index a08e69a..11b34ee 100644
--- a/printing/backend/win_helper.h
+++ b/printing/backend/win_helper.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -12,11 +12,22 @@
 #include <xpsprint.h>
 
 #include "base/string16.h"
+#include "base/win/scoped_handle.h"
 #include "printing/printing_export.h"
 
 // These are helper functions for dealing with Windows Printing.
 namespace printing {
 
+class PrinterHandleTraits {
+ public:
+  static bool CloseHandle(HANDLE handle) {
+    return ::ClosePrinter(handle) != FALSE;
+  }
+};
+
+typedef base::win::GenericScopedHandle<PrinterHandleTraits> ScopedPrinterHandle;
+
+
 // Wrapper class to wrap the XPS APIs (PTxxx APIs). This is needed because these
 // APIs are not available by default on XP. We could delayload prntvpt.dll but
 // this would mean having to add that to every binary that links with
diff --git a/remoting/host/wts_session_process_launcher_win.h b/remoting/host/wts_session_process_launcher_win.h
index e220210..eaf9c67 100644
--- a/remoting/host/wts_session_process_launcher_win.h
+++ b/remoting/host/wts_session_process_launcher_win.h
@@ -13,18 +13,11 @@
 #include "base/process.h"
 #include "base/time.h"
 #include "base/timer.h"
+#include "base/win/scoped_handle.h"
 #include "base/win/object_watcher.h"
 
 #include "remoting/host/wts_console_observer_win.h"
 
-namespace base {
-namespace win {
-
-class ScopedHandle;
-
-} // namespace win
-} // namespace base
-
 namespace remoting {
 
 class WtsConsoleMonitor;