From 4a9b858fbd1fcddcddfff00c8537a48f07f7ae69 Mon Sep 17 00:00:00 2001
From: Scott Graham <scottmg@chromium.org>
Date: Thu, 18 Dec 2014 09:51:20 -0800
Subject: [PATCH] win: Add Scoped...Handle

Intended for future use to implement util/file/file_writer.

There's a similar class in base:
https://code.google.com/p/chromium/codesearch#chromium/src/base/win/scoped_handle.h&l=28

However (perhaps for historical reasons) it does not distinguish between
the possible types of HANDLEs which have different invalid values,
resulting in a need to copy a bunch of code rather than simply using
ScopedGeneric.

Instead, distinguish between the types so the caller can use the
correct one.

Refs:
http://blogs.msdn.com/b/oldnewthing/archive/2004/03/02/82639.aspx
http://msdn.microsoft.com/en-us/magazine/cc302328.aspx (Figure 2)

R=mark@chromium.org
BUG=crashpad:1

Review URL: https://codereview.chromium.org/813873004
---
 util/util.gyp             |  2 ++
 util/win/scoped_handle.cc | 31 +++++++++++++++++++++++++
 util/win/scoped_handle.h  | 49 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 82 insertions(+)
 create mode 100644 util/win/scoped_handle.cc
 create mode 100644 util/win/scoped_handle.h

diff --git a/util/util.gyp b/util/util.gyp
index fe2a5096..b3bdf0ff 100644
--- a/util/util.gyp
+++ b/util/util.gyp
@@ -116,6 +116,8 @@
         'stdlib/strnlen.h',
         'synchronization/semaphore.cc',
         'synchronization/semaphore.h',
+        'win/scoped_handle.cc',
+        'win/scoped_handle.h',
       ],
       'conditions': [
         ['OS=="mac"', {
diff --git a/util/win/scoped_handle.cc b/util/win/scoped_handle.cc
new file mode 100644
index 00000000..34c1ec7b
--- /dev/null
+++ b/util/win/scoped_handle.cc
@@ -0,0 +1,31 @@
+// Copyright 2014 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "util/win/scoped_handle.h"
+
+#include "base/logging.h"
+
+namespace crashpad {
+namespace internal {
+
+void ScopedFileHANDLECloseTraits::Free(HANDLE handle) {
+  PCHECK(CloseHandle(handle));
+}
+
+void ScopedKernelHANDLECloseTraits::Free(HANDLE handle) {
+  PCHECK(CloseHandle(handle));
+}
+
+}  // namespace internal
+}  // namespace crashpad
diff --git a/util/win/scoped_handle.h b/util/win/scoped_handle.h
new file mode 100644
index 00000000..68be4f7b
--- /dev/null
+++ b/util/win/scoped_handle.h
@@ -0,0 +1,49 @@
+// Copyright 2014 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CRASHPAD_UTIL_WIN_SCOPED_HANDLE_H_
+#define CRASHPAD_UTIL_WIN_SCOPED_HANDLE_H_
+
+#include <windows.h>
+
+#include "base/scoped_generic.h"
+
+namespace crashpad {
+
+namespace internal {
+
+struct ScopedFileHANDLECloseTraits {
+  static HANDLE InvalidValue() {
+    return INVALID_HANDLE_VALUE;
+  }
+  static void Free(HANDLE handle);
+};
+
+struct ScopedKernelHANDLECloseTraits {
+  static HANDLE InvalidValue() {
+    return nullptr;
+  }
+  static void Free(HANDLE handle);
+};
+
+}  // namespace internal
+
+using ScopedFileHANDLE =
+    base::ScopedGeneric<HANDLE, internal::ScopedFileHANDLECloseTraits>;
+using ScopedKernelHANDLE =
+    base::ScopedGeneric<HANDLE, internal::ScopedKernelHANDLECloseTraits>;
+
+}  // namespace crashpad
+
+#endif  // CRASHPAD_UTIL_WIN_SCOPED_HANDLE_H_