diff -r 000000000000 -r 6474c204b198 netwerk/base/src/nsTemporaryFileInputStream.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/netwerk/base/src/nsTemporaryFileInputStream.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,54 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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 nsTemporaryFileInputStream_h__
+#define nsTemporaryFileInputStream_h__
+
+#include "mozilla/Mutex.h"
+#include "nsIInputStream.h"
+#include "nsAutoPtr.h"
+#include "prio.h"
+
+class nsTemporaryFileInputStream : public nsIInputStream
+{
+public:
+  //used to release a PRFileDesc
+  class FileDescOwner
+  {
+    friend class nsTemporaryFileInputStream;
+  public:
+    NS_INLINE_DECL_THREADSAFE_REFCOUNTING(FileDescOwner)
+    FileDescOwner(PRFileDesc* aFD)
+      : mFD(aFD),
+        mMutex("FileDescOwner::mMutex")
+    {
+      MOZ_ASSERT(aFD);
+    }
+    ~FileDescOwner()
+    {
+      PR_Close(mFD);
+    }
+    mozilla::Mutex& FileMutex() { return mMutex; }
+
+  private:
+    PRFileDesc* mFD;
+    mozilla::Mutex mMutex;
+  };
+
+  nsTemporaryFileInputStream(FileDescOwner* aFileDescOwner, uint64_t aStartPos, uint64_t aEndPos);
+
+  virtual ~nsTemporaryFileInputStream() { }
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIINPUTSTREAM
+
+private:
+  nsRefPtr<FileDescOwner> mFileDescOwner;
+  uint64_t mStartPos;
+  uint64_t mEndPos;
+  bool mClosed;
+};
+
+#endif // nsTemporaryFileInputStream_h__