| // Copyright 2017 The PDFium Authors |
| // 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/parser/cpdf_flateencoder.h" |
| |
| #include "constants/stream_dict_common.h" |
| #include "core/fpdfapi/parser/cpdf_dictionary.h" |
| #include "core/fpdfapi/parser/cpdf_name.h" |
| #include "core/fpdfapi/parser/cpdf_number.h" |
| #include "core/fpdfapi/parser/cpdf_stream.h" |
| #include "core/fpdfapi/parser/cpdf_stream_acc.h" |
| #include "core/fpdfapi/parser/fpdf_parser_decode.h" |
| #include "core/fxcodec/flate/flatemodule.h" |
| #include "third_party/base/check.h" |
| #include "third_party/base/numerics/safe_conversions.h" |
| |
| CPDF_FlateEncoder::CPDF_FlateEncoder(RetainPtr<const CPDF_Stream> pStream, |
| bool bFlateEncode) |
| : m_pAcc(pdfium::MakeRetain<CPDF_StreamAcc>(pStream)) { |
| m_pAcc->LoadAllDataRaw(); |
| |
| bool bHasFilter = pStream->HasFilter(); |
| if (bHasFilter && !bFlateEncode) { |
| auto pDestAcc = pdfium::MakeRetain<CPDF_StreamAcc>(pStream); |
| pDestAcc->LoadAllDataFiltered(); |
| |
| m_Data = m_pAcc->GetSpan(); |
| m_pClonedDict = ToDictionary(pStream->GetDict()->Clone()); |
| m_pClonedDict->RemoveFor("Filter"); |
| DCHECK(!m_pDict); |
| return; |
| } |
| if (bHasFilter || !bFlateEncode) { |
| m_Data = m_pAcc->GetSpan(); |
| m_pDict = pStream->GetDict(); |
| DCHECK(!m_pClonedDict); |
| return; |
| } |
| |
| // TODO(thestig): Move to Init() and check for empty return value? |
| m_Data = FlateModule::Encode(m_pAcc->GetSpan()); |
| m_pClonedDict = ToDictionary(pStream->GetDict()->Clone()); |
| m_pClonedDict->SetNewFor<CPDF_Number>( |
| "Length", pdfium::base::checked_cast<int>(GetSpan().size())); |
| m_pClonedDict->SetNewFor<CPDF_Name>("Filter", "FlateDecode"); |
| m_pClonedDict->RemoveFor(pdfium::stream::kDecodeParms); |
| DCHECK(!m_pDict); |
| } |
| |
| CPDF_FlateEncoder::~CPDF_FlateEncoder() = default; |
| |
| void CPDF_FlateEncoder::UpdateLength(size_t size) { |
| if (static_cast<size_t>(GetDict()->GetIntegerFor("Length")) == size) |
| return; |
| |
| if (!m_pClonedDict) { |
| m_pClonedDict = ToDictionary(m_pDict->Clone()); |
| m_pDict.Reset(); |
| } |
| DCHECK(m_pClonedDict); |
| DCHECK(!m_pDict); |
| m_pClonedDict->SetNewFor<CPDF_Number>("Length", static_cast<int>(size)); |
| } |
| |
| bool CPDF_FlateEncoder::WriteDictTo(IFX_ArchiveStream* archive, |
| const CPDF_Encryptor* encryptor) const { |
| return GetDict()->WriteTo(archive, encryptor); |
| } |
| |
| const CPDF_Dictionary* CPDF_FlateEncoder::GetDict() const { |
| if (m_pClonedDict) { |
| DCHECK(!m_pDict); |
| return m_pClonedDict.Get(); |
| } |
| return m_pDict.Get(); |
| } |
| |
| pdfium::span<const uint8_t> CPDF_FlateEncoder::GetSpan() const { |
| if (is_owned()) |
| return absl::get<DataVector<uint8_t>>(m_Data); |
| return absl::get<pdfium::span<const uint8_t>>(m_Data); |
| } |