Added ScopedPrinterHandle

base/win/scoped_handle.h

Index: base/win/scoped_handle.h
diff --git a/base/win/scoped_handle.h b/base/win/scoped_handle.h
index 3bb0279648aef9c785a440659c2336b893606ce4..45cab9a53bfe59297debdb37a7de1979ce9a3fcf 100644
--- a/base/win/scoped_handle.h
+++ b/base/win/scoped_handle.h
@@ -30,16 +30,17 @@ namespace win {
 //
 // To explicitly close the handle:
 //   hfile.Close();
-class ScopedHandle {
+template <class Traits>
+class GenericScopedHandle {

[alexeypa (please no reviews), 2012/03/01 21:37:43]

Consider implementing it as

template <class T, class Traits>
class GenericScopedHandle {...};

where T is the raw handle type. This will require abstracting NULL handle
concept via Traits.

[Vitaly Buka (NO REVIEWS), 2012/03/01 22:14:42]

I thought about that. But I'd like to add feature when it needed.

On 2012/03/01 21:37:43, alexeypa wrote:

  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 DefaultHandleTraits {

[alexeypa (please no reviews), 2012/03/01 21:37:43]

Consider renaming it to HandleTraits. It is in a Windows-specific namespace
already, were "handle" means HANDLE. (Win32 HANDLE actually). Other types of
handles usually have some prefix in the name.

[Vitaly Buka (NO REVIEWS), 2012/03/01 22:14:42]

Done.

+ public:
+  static bool CloseHandle(HANDLE handle) {
+    return ::CloseHandle(handle) != FALSE;
+  }
 };
 
+typedef GenericScopedHandle<DefaultHandleTraits> ScopedHandle;
+
 }  // namespace win
 }  // namespace base