Convert IFX_MemoryStream to CFX_MemoryStream

The CFX_MemoryStream is the only implementation of IFX_MemoryStream.
This CL removes the interfaces and uses CFX_MemoryStream directly.

Change-Id: I2f43fa39e82dafa7673517d214ae15fd2d0df331
Reviewed-on: https://pdfium-review.googlesource.com/4391
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/core/fxcrt/cfx_memorystream.h b/core/fxcrt/cfx_memorystream.h
new file mode 100644
index 0000000000..2112280237
--- /dev/null
+++ b/core/fxcrt/cfx_memorystream.h
@@ -0,0 +1,56 @@
+// Copyright 2017 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#ifndef CORE_FXCRT_CFX_MEMORYSTREAM_H_
+#define CORE_FXCRT_CFX_MEMORYSTREAM_H_
+
+#include <vector>
+
+#include "core/fxcrt/cfx_retain_ptr.h"
+#include "core/fxcrt/fx_stream.h"
+
+class CFX_MemoryStream : public IFX_SeekableStream {
+ public:
+  enum Type { kConsecutive = 1 << 0, kTakeOver = 1 << 1 };
+
+  template <typename T, typename... Args>
+  friend CFX_RetainPtr<T> pdfium::MakeRetain(Args&&... args);
+
+  // IFX_SeekableStream
+  FX_FILESIZE GetSize() override;
+  FX_FILESIZE GetPosition() override;
+  bool IsEOF() override;
+  bool ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) override;
+  size_t ReadBlock(void* buffer, size_t size) override;
+  bool WriteBlock(const void* buffer, FX_FILESIZE offset, size_t size) override;
+  bool Flush() override;
+
+  bool IsConsecutive() const { return !!(m_dwFlags & Type::kConsecutive); }
+
+  uint8_t* GetBuffer() const {
+    return !m_Blocks.empty() ? m_Blocks.front() : nullptr;
+  }
+
+  void EstimateSize(size_t nInitSize, size_t nGrowSize);
+  void AttachBuffer(uint8_t* pBuffer, size_t nSize);
+  void DetachBuffer();
+
+ private:
+  explicit CFX_MemoryStream(bool bConsecutive);
+  CFX_MemoryStream(uint8_t* pBuffer, size_t nSize, bool bTakeOver);
+  ~CFX_MemoryStream() override;
+
+  bool ExpandBlocks(size_t size);
+
+  std::vector<uint8_t*> m_Blocks;
+  size_t m_nTotalSize;
+  size_t m_nCurSize;
+  size_t m_nCurPos;
+  size_t m_nGrowSize;
+  uint32_t m_dwFlags;
+};
+
+#endif  // CORE_FXCRT_CFX_MEMORYSTREAM_H_