import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

devtools/shared/heapsnapshot/FileDescriptorOutputStream.h

@@ -0,0 +1,41 @@
+/* -*-  Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_devtools_FileDescriptorOutputStream_h
+#define mozilla_devtools_FileDescriptorOutputStream_h
+
+#include <prio.h>
+
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/ipc/FileDescriptor.h"
+#include "nsIOutputStream.h"
+
+namespace mozilla {
+namespace devtools {
+
+class FileDescriptorOutputStream final : public nsIOutputStream
+{
+private:
+  PRFileDesc* fd;
+
+public:
+  static already_AddRefed<FileDescriptorOutputStream>
+    Create(const ipc::FileDescriptor& fileDescriptor);
+
+private:
+  explicit FileDescriptorOutputStream(PRFileDesc* prfd)
+    : fd(prfd)
+  { }
+
+  virtual ~FileDescriptorOutputStream() { }
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIOUTPUTSTREAM
+};
+
+} // namespace devtools
+} // namespace mozilla
+
+#endif // mozilla_devtools_FileDescriptorOutputStream_h