1 files changed, 77 insertions, 0 deletions
diff --git a/core/fpdfapi/edit/cpdf_flateencoder.cpp b/core/fpdfapi/edit/cpdf_flateencoder.cpp
new file mode 100644
index 0000000000..55d436f573
--- /dev/null
+++ b/core/fpdfapi/edit/cpdf_flateencoder.cpp
@@ -0,0 +1,77 @@
+// 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
+
+#include "core/fpdfapi/edit/cpdf_flateencoder.h"
+
+#include <memory>
+
+#include "core/fpdfapi/parser/cpdf_name.h"
+#include "core/fpdfapi/parser/cpdf_number.h"
+#include "core/fpdfapi/parser/fpdf_parser_decode.h"
+
+CPDF_FlateEncoder::CPDF_FlateEncoder(CPDF_Stream* pStream, bool bFlateEncode)
+    : m_dwSize(0), m_pAcc(pdfium::MakeRetain<CPDF_StreamAcc>(pStream)) {
+  m_pAcc->LoadAllData(true);
+
+  bool bHasFilter = pStream && pStream->HasFilter();
+  if (bHasFilter && !bFlateEncode) {
+    auto pDestAcc = pdfium::MakeRetain<CPDF_StreamAcc>(pStream);
+    pDestAcc->LoadAllData();
+
+    m_dwSize = pDestAcc->GetSize();
+    m_pData = pDestAcc->DetachData();
+    m_pDict = ToDictionary(pStream->GetDict()->Clone());
+    m_pDict->RemoveFor("Filter");
+    return;
+  }
+  if (bHasFilter || !bFlateEncode) {
+    m_pData = const_cast<uint8_t*>(m_pAcc->GetData());
+    m_dwSize = m_pAcc->GetSize();
+    m_pDict = pStream->GetDict();
+    return;
+  }
+
+  // TODO(thestig): Move to Init() and check return value.
+  uint8_t* buffer = nullptr;
+  ::FlateEncode(m_pAcc->GetData(), m_pAcc->GetSize(), &buffer, &m_dwSize);
+
+  m_pData = std::unique_ptr<uint8_t, FxFreeDeleter>(buffer);
+  m_pDict = ToDictionary(pStream->GetDict()->Clone());
+  m_pDict->SetNewFor<CPDF_Number>("Length", static_cast<int>(m_dwSize));
+  m_pDict->SetNewFor<CPDF_Name>("Filter", "FlateDecode");
+  m_pDict->RemoveFor("DecodeParms");
+}
+
+CPDF_FlateEncoder::CPDF_FlateEncoder(const uint8_t* pBuffer,
+                                     uint32_t size,
+                                     bool bFlateEncode,
+                                     bool bXRefStream)
+    : m_dwSize(0) {
+  if (!bFlateEncode) {
+    m_pData = const_cast<uint8_t*>(pBuffer);
+    m_dwSize = size;
+    return;
+  }
+
+  uint8_t* buffer = nullptr;
+  // TODO(thestig): Move to Init() and check return value.
+  if (bXRefStream)
+    ::PngEncode(pBuffer, size, &buffer, &m_dwSize);
+  else
+    ::FlateEncode(pBuffer, size, &buffer, &m_dwSize);
+
+  m_pData = std::unique_ptr<uint8_t, FxFreeDeleter>(buffer);
+}
+
+CPDF_FlateEncoder::~CPDF_FlateEncoder() {}
+
+void CPDF_FlateEncoder::CloneDict() {
+  if (m_pDict.IsOwned())
+    return;
+
+  m_pDict = ToDictionary(m_pDict->Clone());
+  ASSERT(m_pDict.IsOwned());
+}