Get rid of SharedMemory::GiveToProcess.

base/memory/shared_memory_handle_win.cc

 // Copyright 2015 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.
 
 #include "base/memory/shared_memory_handle.h"
 
 #include "base/logging.h"
 
 namespace base {
 
@@ skipping 22 matching lines @@
 void SharedMemoryHandle::Close() const {
   DCHECK(handle_ != nullptr);
   DCHECK(BelongsToCurrentProcess());
   ::CloseHandle(handle_);
 }
 
 bool SharedMemoryHandle::IsValid() const {
   return handle_ != nullptr;
 }
 
+// Duplicates the underlying OS resource.

[Nico, 2017/05/02 15:58:45]

nit: useless comment

[erikchen, 2017/05/02 18:45:57]

Done.

+SharedMemoryHandle SharedMemoryHandle::Duplicate() const {
+  DCHECK(BelongsToCurrentProcess());
+  HANDLE duped_handle;
+  ProcessHandle process = GetCurrentProcess();
+  BOOL success =
+      ::DuplicateHandle(process, handle_, process, &duped_handle, 0,
+                        FALSE, DUPLICATE_SAME_ACCESS);
+  if (success) {

[Nico, 2017/05/02 15:58:45]

nit:

  if (!success)
    return SharedMemoryHandle();
  ...happy case...

keeps the happy path unindented, which imho is a nice thing to aim for

[erikchen, 2017/05/02 18:45:57]

I was wondering if you would nit on this...and bet that you wouldn't. =P

Done.

+    base::SharedMemoryHandle handle(duped_handle, GetCurrentProcId());
+    handle.SetOwnershipPassesToIPC(true);
+    return handle;
+  }
+  return SharedMemoryHandle();
+}
+
 bool SharedMemoryHandle::BelongsToCurrentProcess() const {
   return pid_ == base::GetCurrentProcId();
 }
 
 bool SharedMemoryHandle::NeedsBrokering() const {
   return BelongsToCurrentProcess();
 }
 
 HANDLE SharedMemoryHandle::GetHandle() const {
   return handle_;
 }
 
 base::ProcessId SharedMemoryHandle::GetPID() const {
   return pid_;
 }
 
 void SharedMemoryHandle::SetOwnershipPassesToIPC(bool ownership_passes) {
   ownership_passes_to_ipc_ = ownership_passes;
 }
 
 bool SharedMemoryHandle::OwnershipPassesToIPC() const {
   return ownership_passes_to_ipc_;
 }
 
 }  // namespace base