Mojo: more idiomatic C++ bindings

mojo/public/cpp/bindings/lib/scratch_buffer.h

-// Copyright 2014 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.
-
-#ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_SCRATCH_BUFFER_H_
-#define MOJO_PUBLIC_CPP_BINDINGS_LIB_SCRATCH_BUFFER_H_
-
-#include <deque>
-
-#include "mojo/public/cpp/bindings/buffer.h"
-#include "mojo/public/cpp/system/macros.h"
-
-namespace mojo {
-namespace internal {
-
-// The following class is designed to be allocated on the stack.  If necessary,
-// it will failover to allocating objects on the heap.
-class ScratchBuffer : public Buffer {
- public:
-  ScratchBuffer();
-  virtual ~ScratchBuffer();
-
-  virtual void* Allocate(size_t num_bytes, Destructor func = NULL)
-      MOJO_OVERRIDE;
-
- private:
-  enum {
-    kMinSegmentSize = 512,
-    kMaxSegmentSize = 1024 * 1024 * 1024,
-  };
-
-  struct Segment {
-    Segment* next;
-    char* cursor;
-    char* end;
-  };
-
-  void* AllocateInSegment(Segment* segment, size_t num_bytes);
-  bool AddOverflowSegment(size_t delta);
-
-  char fixed_data_[kMinSegmentSize];
-  Segment fixed_;
-  Segment* overflow_;
-
-  struct PendingDestructor {
-    Destructor func;
-    void* address;
-  };
-  std::deque<PendingDestructor> pending_dtors_;
-
-  MOJO_DISALLOW_COPY_AND_ASSIGN(ScratchBuffer);
-};
-
-}  // namespace internal
-}  // namespace mojo
-
-#endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_SCRATCH_BUFFER_H_