Split off CPDF_Parser and CPDF_SimpleParser into .h/.cpp files

R=dsinclair@chromium.org

Review URL: https://codereview.chromium.org/1773103003 .

17 files changed, 1889 insertions, 1811 deletions

diff --git a/core/src/fpdfapi/fpdf_edit/fpdf_edit_create.cpp b/core/src/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
index ac01bf901c..88bd272e1e 100644
--- a/core/src/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
+++ b/core/src/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
@@ -9,6 +9,7 @@
 #include <vector>
 
 #include "core/include/fpdfapi/cpdf_document.h"
+#include "core/include/fpdfapi/cpdf_parser.h"
 #include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fpdfapi/fpdf_serial.h"
 #include "core/include/fxcrt/fx_ext.h"
diff --git a/core/src/fpdfapi/fpdf_font/fpdf_font.cpp b/core/src/fpdfapi/fpdf_font/fpdf_font.cpp
index d9bc148326..9b4c39aa84 100644
--- a/core/src/fpdfapi/fpdf_font/fpdf_font.cpp
+++ b/core/src/fpdfapi/fpdf_font/fpdf_font.cpp
@@ -7,6 +7,7 @@
 #include "core/src/fpdfapi/fpdf_font/font_int.h"
 
 #include "core/include/fpdfapi/cpdf_document.h"
+#include "core/include/fpdfapi/cpdf_simple_parser.h"
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fpdfapi/fpdf_pageobj.h"
diff --git a/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp b/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
index 38406394c4..1ea686e9e0 100644
--- a/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
+++ b/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
@@ -6,6 +6,7 @@
 
 #include "core/src/fpdfapi/fpdf_font/font_int.h"
 
+#include "core/include/fpdfapi/cpdf_simple_parser.h"
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fpdfapi/fpdf_resource.h"
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_func.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_func.cpp
index f428bf89a1..e9ea7eb74f 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_func.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_func.cpp
@@ -12,6 +12,7 @@
 #include <utility>
 #include <vector>
 
+#include "core/include/fpdfapi/cpdf_simple_parser.h"
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fxcrt/fx_safe_types.h"
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp
index a808c2948b..87e65c4190 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp
@@ -14,6 +14,7 @@
 #include "core/include/fxcodec/fx_codec.h"
 #include "core/include/fxcrt/fx_ext.h"
 #include "core/include/fxcrt/fx_safe_types.h"
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
 
 CPDF_StreamParser::CPDF_StreamParser(const uint8_t* pData, FX_DWORD dwSize) {
   m_pBuf = pData;
diff --git a/core/src/fpdfapi/fpdf_parser/cpdf_document.cpp b/core/src/fpdfapi/fpdf_parser/cpdf_document.cpp
index f837c00509..d97d6e01ff 100644
--- a/core/src/fpdfapi/fpdf_parser/cpdf_document.cpp
+++ b/core/src/fpdfapi/fpdf_parser/cpdf_document.cpp
@@ -8,6 +8,7 @@
 
 #include <set>
 
+#include "core/include/fpdfapi/cpdf_parser.h"
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fxge/fx_font.h"
diff --git a/core/src/fpdfapi/fpdf_parser/cpdf_parser.cpp b/core/src/fpdfapi/fpdf_parser/cpdf_parser.cpp
new file mode 100644
index 0000000000..1871467458
--- /dev/null
+++ b/core/src/fpdfapi/fpdf_parser/cpdf_parser.cpp
@@ -0,0 +1,1643 @@
+// Copyright 2016 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/include/fpdfapi/cpdf_parser.h"
+
+#include "core/include/fpdfapi/cpdf_document.h"
+#include "core/include/fpdfapi/fpdf_parser.h"
+#include "core/include/fxcrt/fx_ext.h"
+#include "core/include/fxcrt/fx_safe_types.h"
+#include "core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.h"
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
+#include "third_party/base/stl_util.h"
+
+namespace {
+
+// A limit on the size of the xref table. Theoretical limits are higher, but
+// this may be large enough in practice.
+const int32_t kMaxXRefSize = 1048576;
+
+// A limit on the maximum object number in the xref table. Theoretical limits
+// are higher, but this may be large enough in practice.
+const FX_DWORD kMaxObjectNumber = 1048576;
+
+FX_DWORD GetVarInt(const uint8_t* p, int32_t n) {
+  FX_DWORD result = 0;
+  for (int32_t i = 0; i < n; ++i)
+    result = result * 256 + p[i];
+  return result;
+}
+
+int32_t GetStreamNCount(CPDF_StreamAcc* pObjStream) {
+  return pObjStream->GetDict()->GetIntegerBy("N");
+}
+
+int32_t GetStreamFirst(CPDF_StreamAcc* pObjStream) {
+  return pObjStream->GetDict()->GetIntegerBy("First");
+}
+
+}  // namespace
+
+CPDF_Parser::CPDF_Parser()
+    : m_pDocument(nullptr),
+      m_bOwnFileRead(true),
+      m_FileVersion(0),
+      m_pTrailer(nullptr),
+      m_pEncryptDict(nullptr),
+      m_pLinearized(nullptr),
+      m_dwFirstPageNo(0),
+      m_dwXrefStartObjNum(0) {
+  m_pSyntax.reset(new CPDF_SyntaxParser);
+}
+
+CPDF_Parser::~CPDF_Parser() {
+  CloseParser();
+}
+
+FX_DWORD CPDF_Parser::GetLastObjNum() const {
+  return m_ObjectInfo.empty() ? 0 : m_ObjectInfo.rbegin()->first;
+}
+
+bool CPDF_Parser::IsValidObjectNumber(FX_DWORD objnum) const {
+  return !m_ObjectInfo.empty() && objnum <= m_ObjectInfo.rbegin()->first;
+}
+
+FX_FILESIZE CPDF_Parser::GetObjectPositionOrZero(FX_DWORD objnum) const {
+  auto it = m_ObjectInfo.find(objnum);
+  return it != m_ObjectInfo.end() ? it->second.pos : 0;
+}
+
+uint8_t CPDF_Parser::GetObjectType(FX_DWORD objnum) const {
+  ASSERT(IsValidObjectNumber(objnum));
+  auto it = m_ObjectInfo.find(objnum);
+  return it != m_ObjectInfo.end() ? it->second.type : 0;
+}
+
+uint16_t CPDF_Parser::GetObjectGenNum(FX_DWORD objnum) const {
+  ASSERT(IsValidObjectNumber(objnum));
+  auto it = m_ObjectInfo.find(objnum);
+  return it != m_ObjectInfo.end() ? it->second.gennum : 0;
+}
+
+bool CPDF_Parser::IsObjectFreeOrNull(FX_DWORD objnum) const {
+  uint8_t type = GetObjectType(objnum);
+  return type == 0 || type == 255;
+}
+
+void CPDF_Parser::SetEncryptDictionary(CPDF_Dictionary* pDict) {
+  m_pEncryptDict = pDict;
+}
+
+CPDF_CryptoHandler* CPDF_Parser::GetCryptoHandler() {
+  return m_pSyntax->m_pCryptoHandler.get();
+}
+
+IFX_FileRead* CPDF_Parser::GetFileAccess() const {
+  return m_pSyntax->m_pFileAccess;
+}
+
+void CPDF_Parser::ShrinkObjectMap(FX_DWORD objnum) {
+  if (objnum == 0) {
+    m_ObjectInfo.clear();
+    return;
+  }
+
+  auto it = m_ObjectInfo.lower_bound(objnum);
+  while (it != m_ObjectInfo.end()) {
+    auto saved_it = it++;
+    m_ObjectInfo.erase(saved_it);
+  }
+
+  if (!pdfium::ContainsKey(m_ObjectInfo, objnum - 1))
+    m_ObjectInfo[objnum - 1].pos = 0;
+}
+
+void CPDF_Parser::CloseParser() {
+  m_bVersionUpdated = FALSE;
+  delete m_pDocument;
+  m_pDocument = nullptr;
+
+  if (m_pTrailer) {
+    m_pTrailer->Release();
+    m_pTrailer = nullptr;
+  }
+  ReleaseEncryptHandler();
+  SetEncryptDictionary(nullptr);
+
+  if (m_bOwnFileRead && m_pSyntax->m_pFileAccess) {
+    m_pSyntax->m_pFileAccess->Release();
+    m_pSyntax->m_pFileAccess = nullptr;
+  }
+
+  m_ObjectStreamMap.clear();
+  m_ObjCache.clear();
+  m_SortedOffset.clear();
+  m_ObjectInfo.clear();
+
+  int32_t iLen = m_Trailers.GetSize();
+  for (int32_t i = 0; i < iLen; ++i) {
+    if (CPDF_Dictionary* trailer = m_Trailers.GetAt(i))
+      trailer->Release();
+  }
+  m_Trailers.RemoveAll();
+
+  if (m_pLinearized) {
+    m_pLinearized->Release();
+    m_pLinearized = nullptr;
+  }
+}
+
+CPDF_Parser::Error CPDF_Parser::StartParse(IFX_FileRead* pFileAccess) {
+  CloseParser();
+
+  m_bXRefStream = FALSE;
+  m_LastXRefOffset = 0;
+  m_bOwnFileRead = true;
+
+  int32_t offset = GetHeaderOffset(pFileAccess);
+  if (offset == -1) {
+    if (pFileAccess)
+      pFileAccess->Release();
+    return FORMAT_ERROR;
+  }
+  m_pSyntax->InitParser(pFileAccess, offset);
+
+  uint8_t ch;
+  if (!m_pSyntax->GetCharAt(5, ch))
+    return FORMAT_ERROR;
+  if (std::isdigit(ch))
+    m_FileVersion = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch)) * 10;
+
+  if (!m_pSyntax->GetCharAt(7, ch))
+    return FORMAT_ERROR;
+  if (std::isdigit(ch))
+    m_FileVersion += FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
+
+  if (m_pSyntax->m_FileLen < m_pSyntax->m_HeaderOffset + 9)
+    return FORMAT_ERROR;
+
+  m_pSyntax->RestorePos(m_pSyntax->m_FileLen - m_pSyntax->m_HeaderOffset - 9);
+  m_pDocument = new CPDF_Document(this);
+
+  FX_BOOL bXRefRebuilt = FALSE;
+  if (m_pSyntax->SearchWord("startxref", TRUE, FALSE, 4096)) {
+    m_SortedOffset.insert(m_pSyntax->SavePos());
+    m_pSyntax->GetKeyword();
+
+    bool bNumber;
+    CFX_ByteString xrefpos_str = m_pSyntax->GetNextWord(&bNumber);
+    if (!bNumber)
+      return FORMAT_ERROR;
+
+    m_LastXRefOffset = (FX_FILESIZE)FXSYS_atoi64(xrefpos_str);
+    if (!LoadAllCrossRefV4(m_LastXRefOffset) &&
+        !LoadAllCrossRefV5(m_LastXRefOffset)) {
+      if (!RebuildCrossRef())
+        return FORMAT_ERROR;
+
+      bXRefRebuilt = TRUE;
+      m_LastXRefOffset = 0;
+    }
+  } else {
+    if (!RebuildCrossRef())
+      return FORMAT_ERROR;
+
+    bXRefRebuilt = TRUE;
+  }
+  Error eRet = SetEncryptHandler();
+  if (eRet != SUCCESS)
+    return eRet;
+
+  m_pDocument->LoadDoc();
+  if (!m_pDocument->GetRoot() || m_pDocument->GetPageCount() == 0) {
+    if (bXRefRebuilt)
+      return FORMAT_ERROR;
+
+    ReleaseEncryptHandler();
+    if (!RebuildCrossRef())
+      return FORMAT_ERROR;
+
+    eRet = SetEncryptHandler();
+    if (eRet != SUCCESS)
+      return eRet;
+
+    m_pDocument->LoadDoc();
+    if (!m_pDocument->GetRoot())
+      return FORMAT_ERROR;
+  }
+  if (GetRootObjNum() == 0) {
+    ReleaseEncryptHandler();
+    if (!RebuildCrossRef() || GetRootObjNum() == 0)
+      return FORMAT_ERROR;
+
+    eRet = SetEncryptHandler();
+    if (eRet != SUCCESS)
+      return eRet;
+  }
+  if (m_pSecurityHandler && !m_pSecurityHandler->IsMetadataEncrypted()) {
+    CPDF_Reference* pMetadata =
+        ToReference(m_pDocument->GetRoot()->GetElement("Metadata"));
+    if (pMetadata)
+      m_pSyntax->m_MetadataObjnum = pMetadata->GetRefObjNum();
+  }
+  return SUCCESS;
+}
+CPDF_Parser::Error CPDF_Parser::SetEncryptHandler() {
+  ReleaseEncryptHandler();
+  SetEncryptDictionary(nullptr);
+
+  if (!m_pTrailer)
+    return FORMAT_ERROR;
+
+  CPDF_Object* pEncryptObj = m_pTrailer->GetElement("Encrypt");
+  if (pEncryptObj) {
+    if (CPDF_Dictionary* pEncryptDict = pEncryptObj->AsDictionary()) {
+      SetEncryptDictionary(pEncryptDict);
+    } else if (CPDF_Reference* pRef = pEncryptObj->AsReference()) {
+      pEncryptObj = m_pDocument->GetIndirectObject(pRef->GetRefObjNum());
+      if (pEncryptObj)
+        SetEncryptDictionary(pEncryptObj->GetDict());
+    }
+  }
+
+  if (m_pEncryptDict) {
+    CFX_ByteString filter = m_pEncryptDict->GetStringBy("Filter");
+    std::unique_ptr<IPDF_SecurityHandler> pSecurityHandler;
+    Error err = HANDLER_ERROR;
+    if (filter == "Standard") {
+      pSecurityHandler.reset(new CPDF_StandardSecurityHandler);
+      err = PASSWORD_ERROR;
+    }
+    if (!pSecurityHandler)
+      return HANDLER_ERROR;
+
+    if (!pSecurityHandler->OnInit(this, m_pEncryptDict))
+      return err;
+
+    m_pSecurityHandler = std::move(pSecurityHandler);
+    std::unique_ptr<CPDF_CryptoHandler> pCryptoHandler(
+        m_pSecurityHandler->CreateCryptoHandler());
+    if (!pCryptoHandler->Init(m_pEncryptDict, m_pSecurityHandler.get()))
+      return HANDLER_ERROR;
+    m_pSyntax->SetEncrypt(std::move(pCryptoHandler));
+  }
+  return SUCCESS;
+}
+
+void CPDF_Parser::ReleaseEncryptHandler() {
+  m_pSyntax->m_pCryptoHandler.reset();
+  m_pSecurityHandler.reset();
+}
+
+FX_FILESIZE CPDF_Parser::GetObjectOffset(FX_DWORD objnum) const {
+  if (!IsValidObjectNumber(objnum))
+    return 0;
+
+  if (GetObjectType(objnum) == 1)
+    return GetObjectPositionOrZero(objnum);
+
+  if (GetObjectType(objnum) == 2) {
+    FX_FILESIZE pos = GetObjectPositionOrZero(objnum);
+    return GetObjectPositionOrZero(pos);
+  }
+  return 0;
+}
+
+FX_BOOL CPDF_Parser::LoadAllCrossRefV4(FX_FILESIZE xrefpos) {
+  if (!LoadCrossRefV4(xrefpos, 0, TRUE))
+    return FALSE;
+
+  m_pTrailer = LoadTrailerV4();
+  if (!m_pTrailer)
+    return FALSE;
+
+  int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
+  if (xrefsize > 0 && xrefsize <= kMaxXRefSize)
+    ShrinkObjectMap(xrefsize);
+
+  std::vector<FX_FILESIZE> CrossRefList;
+  std::vector<FX_FILESIZE> XRefStreamList;
+  std::set<FX_FILESIZE> seen_xrefpos;
+
+  CrossRefList.push_back(xrefpos);
+  XRefStreamList.push_back(GetDirectInteger(m_pTrailer, "XRefStm"));
+  seen_xrefpos.insert(xrefpos);
+
+  // When |m_pTrailer| doesn't have Prev entry or Prev entry value is not
+  // numerical, GetDirectInteger() returns 0. Loading will end.
+  xrefpos = GetDirectInteger(m_pTrailer, "Prev");
+  while (xrefpos) {
+    // Check for circular references.
+    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+      return FALSE;
+
+    seen_xrefpos.insert(xrefpos);
+
+    // SLOW ...
+    CrossRefList.insert(CrossRefList.begin(), xrefpos);
+    LoadCrossRefV4(xrefpos, 0, TRUE);
+
+    std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
+        LoadTrailerV4());
+    if (!pDict)
+      return FALSE;
+
+    xrefpos = GetDirectInteger(pDict.get(), "Prev");
+
+    // SLOW ...
+    XRefStreamList.insert(XRefStreamList.begin(),
+                          pDict->GetIntegerBy("XRefStm"));
+    m_Trailers.Add(pDict.release());
+  }
+
+  for (size_t i = 0; i < CrossRefList.size(); ++i) {
+    if (!LoadCrossRefV4(CrossRefList[i], XRefStreamList[i], FALSE))
+      return FALSE;
+  }
+  return TRUE;
+}
+
+FX_BOOL CPDF_Parser::LoadLinearizedAllCrossRefV4(FX_FILESIZE xrefpos,
+                                                 FX_DWORD dwObjCount) {
+  if (!LoadLinearizedCrossRefV4(xrefpos, dwObjCount))
+    return FALSE;
+
+  m_pTrailer = LoadTrailerV4();
+  if (!m_pTrailer)
+    return FALSE;
+
+  int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
+  if (xrefsize == 0)
+    return FALSE;
+
+  std::vector<FX_FILESIZE> CrossRefList;
+  std::vector<FX_FILESIZE> XRefStreamList;
+  std::set<FX_FILESIZE> seen_xrefpos;
+
+  CrossRefList.push_back(xrefpos);
+  XRefStreamList.push_back(GetDirectInteger(m_pTrailer, "XRefStm"));
+  seen_xrefpos.insert(xrefpos);
+
+  xrefpos = GetDirectInteger(m_pTrailer, "Prev");
+  while (xrefpos) {
+    // Check for circular references.
+    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+      return FALSE;
+
+    seen_xrefpos.insert(xrefpos);
+
+    // SLOW ...
+    CrossRefList.insert(CrossRefList.begin(), xrefpos);
+    LoadCrossRefV4(xrefpos, 0, TRUE);
+
+    std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
+        LoadTrailerV4());
+    if (!pDict)
+      return FALSE;
+
+    xrefpos = GetDirectInteger(pDict.get(), "Prev");
+
+    // SLOW ...
+    XRefStreamList.insert(XRefStreamList.begin(),
+                          pDict->GetIntegerBy("XRefStm"));
+    m_Trailers.Add(pDict.release());
+  }
+
+  for (size_t i = 1; i < CrossRefList.size(); ++i) {
+    if (!LoadCrossRefV4(CrossRefList[i], XRefStreamList[i], FALSE))
+      return FALSE;
+  }
+  return TRUE;
+}
+
+FX_BOOL CPDF_Parser::LoadLinearizedCrossRefV4(FX_FILESIZE pos,
+                                              FX_DWORD dwObjCount) {
+  FX_FILESIZE dwStartPos = pos - m_pSyntax->m_HeaderOffset;
+
+  m_pSyntax->RestorePos(dwStartPos);
+  m_SortedOffset.insert(pos);
+
+  FX_DWORD start_objnum = 0;
+  FX_DWORD count = dwObjCount;
+  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+
+  const int32_t recordsize = 20;
+  std::vector<char> buf(1024 * recordsize + 1);
+  buf[1024 * recordsize] = '\0';
+
+  int32_t nBlocks = count / 1024 + 1;
+  for (int32_t block = 0; block < nBlocks; block++) {
+    int32_t block_size = block == nBlocks - 1 ? count % 1024 : 1024;
+    FX_DWORD dwReadSize = block_size * recordsize;
+    if ((FX_FILESIZE)(dwStartPos + dwReadSize) > m_pSyntax->m_FileLen)
+      return FALSE;
+
+    if (!m_pSyntax->ReadBlock(reinterpret_cast<uint8_t*>(buf.data()),
+                              dwReadSize)) {
+      return FALSE;
+    }
+
+    for (int32_t i = 0; i < block_size; i++) {
+      FX_DWORD objnum = start_objnum + block * 1024 + i;
+      char* pEntry = &buf[i * recordsize];
+      if (pEntry[17] == 'f') {
+        m_ObjectInfo[objnum].pos = 0;
+        m_ObjectInfo[objnum].type = 0;
+      } else {
+        int32_t offset = FXSYS_atoi(pEntry);
+        if (offset == 0) {
+          for (int32_t c = 0; c < 10; c++) {
+            if (!std::isdigit(pEntry[c]))
+              return FALSE;
+          }
+        }
+
+        m_ObjectInfo[objnum].pos = offset;
+        int32_t version = FXSYS_atoi(pEntry + 11);
+        if (version >= 1)
+          m_bVersionUpdated = TRUE;
+
+        m_ObjectInfo[objnum].gennum = version;
+        if (m_ObjectInfo[objnum].pos < m_pSyntax->m_FileLen)
+          m_SortedOffset.insert(m_ObjectInfo[objnum].pos);
+
+        m_ObjectInfo[objnum].type = 1;
+      }
+    }
+  }
+  m_pSyntax->RestorePos(SavedPos + count * recordsize);
+  return TRUE;
+}
+
+bool CPDF_Parser::LoadCrossRefV4(FX_FILESIZE pos,
+                                 FX_FILESIZE streampos,
+                                 FX_BOOL bSkip) {
+  m_pSyntax->RestorePos(pos);
+  if (m_pSyntax->GetKeyword() != "xref")
+    return false;
+
+  m_SortedOffset.insert(pos);
+  if (streampos)
+    m_SortedOffset.insert(streampos);
+
+  while (1) {
+    FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+    bool bIsNumber;
+    CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+    if (word.IsEmpty())
+      return false;
+
+    if (!bIsNumber) {
+      m_pSyntax->RestorePos(SavedPos);
+      break;
+    }
+
+    FX_DWORD start_objnum = FXSYS_atoui(word);
+    if (start_objnum >= kMaxObjectNumber)
+      return false;
+
+    FX_DWORD count = m_pSyntax->GetDirectNum();
+    m_pSyntax->ToNextWord();
+    SavedPos = m_pSyntax->SavePos();
+    const int32_t recordsize = 20;
+
+    m_dwXrefStartObjNum = start_objnum;
+    if (!bSkip) {
+      std::vector<char> buf(1024 * recordsize + 1);
+      buf[1024 * recordsize] = '\0';
+
+      int32_t nBlocks = count / 1024 + 1;
+      for (int32_t block = 0; block < nBlocks; block++) {
+        int32_t block_size = block == nBlocks - 1 ? count % 1024 : 1024;
+        m_pSyntax->ReadBlock(reinterpret_cast<uint8_t*>(buf.data()),
+                             block_size * recordsize);
+
+        for (int32_t i = 0; i < block_size; i++) {
+          FX_DWORD objnum = start_objnum + block * 1024 + i;
+          char* pEntry = &buf[i * recordsize];
+          if (pEntry[17] == 'f') {
+            m_ObjectInfo[objnum].pos = 0;
+            m_ObjectInfo[objnum].type = 0;
+          } else {
+            FX_FILESIZE offset = (FX_FILESIZE)FXSYS_atoi64(pEntry);
+            if (offset == 0) {
+              for (int32_t c = 0; c < 10; c++) {
+                if (!std::isdigit(pEntry[c]))
+                  return false;
+              }
+            }
+
+            m_ObjectInfo[objnum].pos = offset;
+            int32_t version = FXSYS_atoi(pEntry + 11);
+            if (version >= 1)
+              m_bVersionUpdated = TRUE;
+
+            m_ObjectInfo[objnum].gennum = version;
+            if (m_ObjectInfo[objnum].pos < m_pSyntax->m_FileLen)
+              m_SortedOffset.insert(m_ObjectInfo[objnum].pos);
+
+            m_ObjectInfo[objnum].type = 1;
+          }
+        }
+      }
+    }
+    m_pSyntax->RestorePos(SavedPos + count * recordsize);
+  }
+  return !streampos || LoadCrossRefV5(&streampos, FALSE);
+}
+
+FX_BOOL CPDF_Parser::LoadAllCrossRefV5(FX_FILESIZE xrefpos) {
+  if (!LoadCrossRefV5(&xrefpos, TRUE))
+    return FALSE;
+
+  std::set<FX_FILESIZE> seen_xrefpos;
+  while (xrefpos) {
+    seen_xrefpos.insert(xrefpos);
+    if (!LoadCrossRefV5(&xrefpos, FALSE))
+      return FALSE;
+
+    // Check for circular references.
+    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+      return FALSE;
+  }
+  m_ObjectStreamMap.clear();
+  m_bXRefStream = TRUE;
+  return TRUE;
+}
+
+FX_BOOL CPDF_Parser::RebuildCrossRef() {
+  m_ObjectInfo.clear();
+  m_SortedOffset.clear();
+  if (m_pTrailer) {
+    m_pTrailer->Release();
+    m_pTrailer = nullptr;
+  }
+
+  ParserState state = ParserState::kDefault;
+
+  int32_t inside_index = 0;
+  FX_DWORD objnum = 0;
+  FX_DWORD gennum = 0;
+  int32_t depth = 0;
+
+  const FX_DWORD kBufferSize = 4096;
+  std::vector<uint8_t> buffer(kBufferSize);
+
+  FX_FILESIZE pos = m_pSyntax->m_HeaderOffset;
+  FX_FILESIZE start_pos = 0;
+  FX_FILESIZE start_pos1 = 0;
+  FX_FILESIZE last_obj = -1;
+  FX_FILESIZE last_xref = -1;
+  FX_FILESIZE last_trailer = -1;
+
+  while (pos < m_pSyntax->m_FileLen) {
+    const FX_FILESIZE saved_pos = pos;
+    bool bOverFlow = false;
+    FX_DWORD size =
+        std::min((FX_DWORD)(m_pSyntax->m_FileLen - pos), kBufferSize);
+    if (!m_pSyntax->m_pFileAccess->ReadBlock(buffer.data(), pos, size))
+      break;
+
+    for (FX_DWORD i = 0; i < size; i++) {
+      uint8_t byte = buffer[i];
+      switch (state) {
+        case ParserState::kDefault:
+          if (PDFCharIsWhitespace(byte)) {
+            state = ParserState::kWhitespace;
+          } else if (std::isdigit(byte)) {
+            --i;
+            state = ParserState::kWhitespace;
+          } else if (byte == '%') {
+            inside_index = 0;
+            state = ParserState::kComment;
+          } else if (byte == '(') {
+            state = ParserState::kString;
+            depth = 1;
+          } else if (byte == '<') {
+            inside_index = 1;
+            state = ParserState::kHexString;
+          } else if (byte == '\\') {
+            state = ParserState::kEscapedString;
+          } else if (byte == 't') {
+            state = ParserState::kTrailer;
+            inside_index = 1;
+          }
+          break;
+
+        case ParserState::kWhitespace:
+          if (std::isdigit(byte)) {
+            start_pos = pos + i;
+            state = ParserState::kObjNum;
+            objnum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+          } else if (byte == 't') {
+            state = ParserState::kTrailer;
+            inside_index = 1;
+          } else if (byte == 'x') {
+            state = ParserState::kXref;
+            inside_index = 1;
+          } else if (!PDFCharIsWhitespace(byte)) {
+            --i;
+            state = ParserState::kDefault;
+          }
+          break;
+
+        case ParserState::kObjNum:
+          if (std::isdigit(byte)) {
+            objnum =
+                objnum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+          } else if (PDFCharIsWhitespace(byte)) {
+            state = ParserState::kPostObjNum;
+          } else {
+            --i;
+            state = ParserState::kEndObj;
+            inside_index = 0;
+          }
+          break;
+
+        case ParserState::kPostObjNum:
+          if (std::isdigit(byte)) {
+            start_pos1 = pos + i;
+            state = ParserState::kGenNum;
+            gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+          } else if (byte == 't') {
+            state = ParserState::kTrailer;
+            inside_index = 1;
+          } else if (!PDFCharIsWhitespace(byte)) {
+            --i;
+            state = ParserState::kDefault;
+          }
+          break;
+
+        case ParserState::kGenNum:
+          if (std::isdigit(byte)) {
+            gennum =
+                gennum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+          } else if (PDFCharIsWhitespace(byte)) {
+            state = ParserState::kPostGenNum;
+          } else {
+            --i;
+            state = ParserState::kDefault;
+          }
+          break;
+
+        case ParserState::kPostGenNum:
+          if (byte == 'o') {
+            state = ParserState::kBeginObj;
+            inside_index = 1;
+          } else if (std::isdigit(byte)) {
+            objnum = gennum;
+            gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
+            start_pos = start_pos1;
+            start_pos1 = pos + i;
+            state = ParserState::kGenNum;
+          } else if (byte == 't') {
+            state = ParserState::kTrailer;
+            inside_index = 1;
+          } else if (!PDFCharIsWhitespace(byte)) {
+            --i;
+            state = ParserState::kDefault;
+          }
+          break;
+
+        case ParserState::kBeginObj:
+          switch (inside_index) {
+            case 1:
+              if (byte != 'b') {
+                --i;
+                state = ParserState::kDefault;
+              } else {
+                inside_index++;
+              }
+              break;
+            case 2:
+              if (byte != 'j') {
+                --i;
+                state = ParserState::kDefault;
+              } else {
+                inside_index++;
+              }
+              break;
+            case 3:
+              if (PDFCharIsWhitespace(byte) || PDFCharIsDelimiter(byte)) {
+                FX_FILESIZE obj_pos = start_pos - m_pSyntax->m_HeaderOffset;
+                m_SortedOffset.insert(obj_pos);
+                last_obj = start_pos;
+                FX_FILESIZE obj_end = 0;
+                CPDF_Object* pObject = ParseIndirectObjectAtByStrict(
+                    m_pDocument, obj_pos, objnum, &obj_end);
+                if (CPDF_Stream* pStream = ToStream(pObject)) {
+                  if (CPDF_Dictionary* pDict = pStream->GetDict()) {
+                    if ((pDict->KeyExist("Type")) &&
+                        (pDict->GetStringBy("Type") == "XRef" &&
+                         pDict->KeyExist("Size"))) {
+                      CPDF_Object* pRoot = pDict->GetElement("Root");
+                      if (pRoot && pRoot->GetDict() &&
+                          pRoot->GetDict()->GetElement("Pages")) {
+                        if (m_pTrailer)
+                          m_pTrailer->Release();
+                        m_pTrailer = ToDictionary(pDict->Clone());
+                      }
+                    }
+                  }
+                }
+
+                FX_FILESIZE offset = 0;
+                m_pSyntax->RestorePos(obj_pos);
+                offset = m_pSyntax->FindTag("obj", 0);
+                if (offset == -1)
+                  offset = 0;
+                else
+                  offset += 3;
+
+                FX_FILESIZE nLen = obj_end - obj_pos - offset;
+                if ((FX_DWORD)nLen > size - i) {
+                  pos = obj_end + m_pSyntax->m_HeaderOffset;
+                  bOverFlow = true;
+                } else {
+                  i += (FX_DWORD)nLen;
+                }
+
+                if (!m_ObjectInfo.empty() && IsValidObjectNumber(objnum) &&
+                    m_ObjectInfo[objnum].pos) {
+                  if (pObject) {
+                    FX_DWORD oldgen = GetObjectGenNum(objnum);
+                    m_ObjectInfo[objnum].pos = obj_pos;
+                    m_ObjectInfo[objnum].gennum = gennum;
+                    if (oldgen != gennum)
+                      m_bVersionUpdated = TRUE;
+                  }
+                } else {
+                  m_ObjectInfo[objnum].pos = obj_pos;
+                  m_ObjectInfo[objnum].type = 1;
+                  m_ObjectInfo[objnum].gennum = gennum;
+                }
+
+                if (pObject)
+                  pObject->Release();
+              }
+              --i;
+              state = ParserState::kDefault;
+              break;
+          }
+          break;
+
+        case ParserState::kTrailer:
+          if (inside_index == 7) {
+            if (PDFCharIsWhitespace(byte) || PDFCharIsDelimiter(byte)) {
+              last_trailer = pos + i - 7;
+              m_pSyntax->RestorePos(pos + i - m_pSyntax->m_HeaderOffset);
+
+              CPDF_Object* pObj = m_pSyntax->GetObject(m_pDocument, 0, 0, true);
+              if (pObj) {
+                if (!pObj->IsDictionary() && !pObj->AsStream()) {
+                  pObj->Release();
+                } else {
+                  CPDF_Stream* pStream = pObj->AsStream();
+                  if (CPDF_Dictionary* pTrailer =
+                          pStream ? pStream->GetDict() : pObj->AsDictionary()) {
+                    if (m_pTrailer) {
+                      CPDF_Object* pRoot = pTrailer->GetElement("Root");
+                      CPDF_Reference* pRef = ToReference(pRoot);
+                      if (!pRoot ||
+                          (pRef && IsValidObjectNumber(pRef->GetRefObjNum()) &&
+                           m_ObjectInfo[pRef->GetRefObjNum()].pos != 0)) {
+                        auto it = pTrailer->begin();
+                        while (it != pTrailer->end()) {
+                          const CFX_ByteString& key = it->first;
+                          CPDF_Object* pElement = it->second;
+                          ++it;
+                          FX_DWORD dwObjNum =
+                              pElement ? pElement->GetObjNum() : 0;
+                          if (dwObjNum) {
+                            m_pTrailer->SetAtReference(key, m_pDocument,
+                                                       dwObjNum);
+                          } else {
+                            m_pTrailer->SetAt(key, pElement->Clone());
+                          }
+                        }
+                      }
+                      pObj->Release();
+                    } else {
+                      if (pObj->IsStream()) {
+                        m_pTrailer = ToDictionary(pTrailer->Clone());
+                        pObj->Release();
+                      } else {
+                        m_pTrailer = pTrailer;
+                      }
+
+                      FX_FILESIZE dwSavePos = m_pSyntax->SavePos();
+                      CFX_ByteString strWord = m_pSyntax->GetKeyword();
+                      if (!strWord.Compare("startxref")) {
+                        bool bNumber;
+                        CFX_ByteString bsOffset =
+                            m_pSyntax->GetNextWord(&bNumber);
+                        if (bNumber)
+                          m_LastXRefOffset = FXSYS_atoi(bsOffset);
+                      }
+                      m_pSyntax->RestorePos(dwSavePos);
+                    }
+                  } else {
+                    pObj->Release();
+                  }
+                }
+              }
+            }
+            --i;
+            state = ParserState::kDefault;
+          } else if (byte == "trailer"[inside_index]) {
+            inside_index++;
+          } else {
+            --i;
+            state = ParserState::kDefault;
+          }
+          break;
+
+        case ParserState::kXref:
+          if (inside_index == 4) {
+            last_xref = pos + i - 4;
+            state = ParserState::kWhitespace;
+          } else if (byte == "xref"[inside_index]) {
+            inside_index++;
+          } else {
+            --i;
+            state = ParserState::kDefault;
+          }
+          break;
+
+        case ParserState::kComment:
+          if (PDFCharIsLineEnding(byte))
+            state = ParserState::kDefault;
+          break;
+
+        case ParserState::kString:
+          if (byte == ')') {
+            if (depth > 0)
+              depth--;
+          } else if (byte == '(') {
+            depth++;
+          }
+
+          if (!depth)
+            state = ParserState::kDefault;
+          break;
+
+        case ParserState::kHexString:
+          if (byte == '>' || (byte == '<' && inside_index == 1))
+            state = ParserState::kDefault;
+          inside_index = 0;
+          break;
+
+        case ParserState::kEscapedString:
+          if (PDFCharIsDelimiter(byte) || PDFCharIsWhitespace(byte)) {
+            --i;
+            state = ParserState::kDefault;
+          }
+          break;
+
+        case ParserState::kEndObj:
+          if (PDFCharIsWhitespace(byte)) {
+            state = ParserState::kDefault;
+          } else if (byte == '%' || byte == '(' || byte == '<' ||
+                     byte == '\\') {
+            state = ParserState::kDefault;
+            --i;
+          } else if (inside_index == 6) {
+            state = ParserState::kDefault;
+            --i;
+          } else if (byte == "endobj"[inside_index]) {
+            inside_index++;
+          }
+          break;
+      }
+
+      if (bOverFlow) {
+        size = 0;
+        break;
+      }
+    }
+    pos += size;
+
+    // If the position has not changed at all in a loop iteration, then break
+    // out to prevent infinite looping.
+    if (pos == saved_pos)
+      break;
+  }
+
+  if (last_xref != -1 && last_xref > last_obj)
+    last_trailer = last_xref;
+  else if (last_trailer == -1 || last_xref < last_obj)
+    last_trailer = m_pSyntax->m_FileLen;
+
+  m_SortedOffset.insert(last_trailer - m_pSyntax->m_HeaderOffset);
+  return m_pTrailer && !m_ObjectInfo.empty();
+}
+
+FX_BOOL CPDF_Parser::LoadCrossRefV5(FX_FILESIZE* pos, FX_BOOL bMainXRef) {
+  CPDF_Object* pObject = ParseIndirectObjectAt(m_pDocument, *pos, 0);
+  if (!pObject)
+    return FALSE;
+
+  if (m_pDocument) {
+    FX_BOOL bInserted = FALSE;
+    CPDF_Dictionary* pDict = m_pDocument->GetRoot();
+    if (!pDict || pDict->GetObjNum() != pObject->m_ObjNum) {
+      bInserted = m_pDocument->InsertIndirectObject(pObject->m_ObjNum, pObject);
+    } else {
+      if (pObject->IsStream())
+        pObject->Release();
+    }
+
+    if (!bInserted)
+      return FALSE;
+  }
+
+  CPDF_Stream* pStream = pObject->AsStream();
+  if (!pStream)
+    return FALSE;
+
+  *pos = pStream->GetDict()->GetIntegerBy("Prev");
+  int32_t size = pStream->GetDict()->GetIntegerBy("Size");
+  if (size < 0) {
+    pStream->Release();
+    return FALSE;
+  }
+
+  if (bMainXRef) {
+    m_pTrailer = ToDictionary(pStream->GetDict()->Clone());
+    ShrinkObjectMap(size);
+    for (auto& it : m_ObjectInfo)
+      it.second.type = 0;
+  } else {
+    m_Trailers.Add(ToDictionary(pStream->GetDict()->Clone()));
+  }
+
+  std::vector<std::pair<int32_t, int32_t>> arrIndex;
+  CPDF_Array* pArray = pStream->GetDict()->GetArrayBy("Index");
+  if (pArray) {
+    FX_DWORD nPairSize = pArray->GetCount() / 2;
+    for (FX_DWORD i = 0; i < nPairSize; i++) {
+      CPDF_Object* pStartNumObj = pArray->GetElement(i * 2);
+      CPDF_Object* pCountObj = pArray->GetElement(i * 2 + 1);
+
+      if (ToNumber(pStartNumObj) && ToNumber(pCountObj)) {
+        int nStartNum = pStartNumObj->GetInteger();
+        int nCount = pCountObj->GetInteger();
+        if (nStartNum >= 0 && nCount > 0)
+          arrIndex.push_back(std::make_pair(nStartNum, nCount));
+      }
+    }
+  }
+
+  if (arrIndex.size() == 0)
+    arrIndex.push_back(std::make_pair(0, size));
+
+  pArray = pStream->GetDict()->GetArrayBy("W");
+  if (!pArray) {
+    pStream->Release();
+    return FALSE;
+  }
+
+  CFX_DWordArray WidthArray;
+  FX_SAFE_DWORD dwAccWidth = 0;
+  for (FX_DWORD i = 0; i < pArray->GetCount(); i++) {
+    WidthArray.Add(pArray->GetIntegerAt(i));
+    dwAccWidth += WidthArray[i];
+  }
+
+  if (!dwAccWidth.IsValid() || WidthArray.GetSize() < 3) {
+    pStream->Release();
+    return FALSE;
+  }
+
+  FX_DWORD totalWidth = dwAccWidth.ValueOrDie();
+  CPDF_StreamAcc acc;
+  acc.LoadAllData(pStream);
+
+  const uint8_t* pData = acc.GetData();
+  FX_DWORD dwTotalSize = acc.GetSize();
+  FX_DWORD segindex = 0;
+  for (FX_DWORD i = 0; i < arrIndex.size(); i++) {
+    int32_t startnum = arrIndex[i].first;
+    if (startnum < 0)
+      continue;
+
+    m_dwXrefStartObjNum =
+        pdfium::base::checked_cast<FX_DWORD, int32_t>(startnum);
+    FX_DWORD count =
+        pdfium::base::checked_cast<FX_DWORD, int32_t>(arrIndex[i].second);
+    FX_SAFE_DWORD dwCaculatedSize = segindex;
+    dwCaculatedSize += count;
+    dwCaculatedSize *= totalWidth;
+    if (!dwCaculatedSize.IsValid() ||
+        dwCaculatedSize.ValueOrDie() > dwTotalSize) {
+      continue;
+    }
+
+    const uint8_t* segstart = pData + segindex * totalWidth;
+    FX_SAFE_DWORD dwMaxObjNum = startnum;
+    dwMaxObjNum += count;
+    FX_DWORD dwV5Size = m_ObjectInfo.empty() ? 0 : GetLastObjNum() + 1;
+    if (!dwMaxObjNum.IsValid() || dwMaxObjNum.ValueOrDie() > dwV5Size)
+      continue;
+
+    for (FX_DWORD j = 0; j < count; j++) {
+      int32_t type = 1;
+      const uint8_t* entrystart = segstart + j * totalWidth;
+      if (WidthArray[0])
+        type = GetVarInt(entrystart, WidthArray[0]);
+
+      if (GetObjectType(startnum + j) == 255) {
+        FX_FILESIZE offset =
+            GetVarInt(entrystart + WidthArray[0], WidthArray[1]);
+        m_ObjectInfo[startnum + j].pos = offset;
+        m_SortedOffset.insert(offset);
+        continue;
+      }
+
+      if (GetObjectType(startnum + j))
+        continue;
+
+      m_ObjectInfo[startnum + j].type = type;
+      if (type == 0) {
+        m_ObjectInfo[startnum + j].pos = 0;
+      } else {
+        FX_FILESIZE offset =
+            GetVarInt(entrystart + WidthArray[0], WidthArray[1]);
+        m_ObjectInfo[startnum + j].pos = offset;
+        if (type == 1) {
+          m_SortedOffset.insert(offset);
+        } else {
+          if (offset < 0 || !IsValidObjectNumber(offset)) {
+            pStream->Release();
+            return FALSE;
+          }
+          m_ObjectInfo[offset].type = 255;
+        }
+      }
+    }
+    segindex += count;
+  }
+  pStream->Release();
+  return TRUE;
+}
+
+CPDF_Array* CPDF_Parser::GetIDArray() {
+  CPDF_Object* pID = m_pTrailer ? m_pTrailer->GetElement("ID") : nullptr;
+  if (!pID)
+    return nullptr;
+
+  if (CPDF_Reference* pRef = pID->AsReference()) {
+    pID = ParseIndirectObject(nullptr, pRef->GetRefObjNum());
+    m_pTrailer->SetAt("ID", pID);
+  }
+  return ToArray(pID);
+}
+
+FX_DWORD CPDF_Parser::GetRootObjNum() {
+  CPDF_Reference* pRef =
+      ToReference(m_pTrailer ? m_pTrailer->GetElement("Root") : nullptr);
+  return pRef ? pRef->GetRefObjNum() : 0;
+}
+
+FX_DWORD CPDF_Parser::GetInfoObjNum() {
+  CPDF_Reference* pRef =
+      ToReference(m_pTrailer ? m_pTrailer->GetElement("Info") : nullptr);
+  return pRef ? pRef->GetRefObjNum() : 0;
+}
+
+FX_BOOL CPDF_Parser::IsFormStream(FX_DWORD objnum, FX_BOOL& bForm) {
+  bForm = FALSE;
+  if (!IsValidObjectNumber(objnum))
+    return TRUE;
+
+  if (GetObjectType(objnum) == 0)
+    return TRUE;
+
+  if (GetObjectType(objnum) == 2)
+    return TRUE;
+
+  FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
+  auto it = m_SortedOffset.find(pos);
+  if (it == m_SortedOffset.end())
+    return TRUE;
+
+  if (++it == m_SortedOffset.end())
+    return FALSE;
+
+  FX_FILESIZE size = *it - pos;
+  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+  m_pSyntax->RestorePos(pos);
+
+  const char kFormStream[] = "/Form\0stream";
+  const CFX_ByteStringC kFormStreamStr(kFormStream, sizeof(kFormStream) - 1);
+  bForm = m_pSyntax->SearchMultiWord(kFormStreamStr, TRUE, size) == 0;
+  m_pSyntax->RestorePos(SavedPos);
+  return TRUE;
+}
+
+CPDF_Object* CPDF_Parser::ParseIndirectObject(
+    CPDF_IndirectObjectHolder* pObjList,
+    FX_DWORD objnum) {
+  if (!IsValidObjectNumber(objnum))
+    return nullptr;
+
+  // Prevent circular parsing the same object.
+  if (pdfium::ContainsKey(m_ParsingObjNums, objnum))
+    return nullptr;
+  ScopedSetInsertion<FX_DWORD> local_insert(&m_ParsingObjNums, objnum);
+
+  if (GetObjectType(objnum) == 1 || GetObjectType(objnum) == 255) {
+    FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
+    if (pos <= 0)
+      return nullptr;
+    return ParseIndirectObjectAt(pObjList, pos, objnum);
+  }
+  if (GetObjectType(objnum) != 2)
+    return nullptr;
+
+  CPDF_StreamAcc* pObjStream = GetObjectStream(m_ObjectInfo[objnum].pos);
+  if (!pObjStream)
+    return nullptr;
+
+  ScopedFileStream file(FX_CreateMemoryStream(
+      (uint8_t*)pObjStream->GetData(), (size_t)pObjStream->GetSize(), FALSE));
+  CPDF_SyntaxParser syntax;
+  syntax.InitParser(file.get(), 0);
+  const int32_t offset = GetStreamFirst(pObjStream);
+
+  // Read object numbers from |pObjStream| into a cache.
+  if (!pdfium::ContainsKey(m_ObjCache, pObjStream)) {
+    for (int32_t i = GetStreamNCount(pObjStream); i > 0; --i) {
+      FX_DWORD thisnum = syntax.GetDirectNum();
+      FX_DWORD thisoff = syntax.GetDirectNum();
+      m_ObjCache[pObjStream][thisnum] = thisoff;
+    }
+  }
+
+  const auto it = m_ObjCache[pObjStream].find(objnum);
+  if (it == m_ObjCache[pObjStream].end())
+    return nullptr;
+
+  syntax.RestorePos(offset + it->second);
+  return syntax.GetObject(pObjList, 0, 0, true);
+}
+
+CPDF_StreamAcc* CPDF_Parser::GetObjectStream(FX_DWORD objnum) {
+  auto it = m_ObjectStreamMap.find(objnum);
+  if (it != m_ObjectStreamMap.end())
+    return it->second.get();
+
+  if (!m_pDocument)
+    return nullptr;
+
+  const CPDF_Stream* pStream = ToStream(m_pDocument->GetIndirectObject(objnum));
+  if (!pStream)
+    return nullptr;
+
+  CPDF_StreamAcc* pStreamAcc = new CPDF_StreamAcc;
+  pStreamAcc->LoadAllData(pStream);
+  m_ObjectStreamMap[objnum].reset(pStreamAcc);
+  return pStreamAcc;
+}
+
+FX_FILESIZE CPDF_Parser::GetObjectSize(FX_DWORD objnum) const {
+  if (!IsValidObjectNumber(objnum))
+    return 0;
+
+  if (GetObjectType(objnum) == 2)
+    objnum = GetObjectPositionOrZero(objnum);
+
+  if (GetObjectType(objnum) != 1 && GetObjectType(objnum) != 255)
+    return 0;
+
+  FX_FILESIZE offset = GetObjectPositionOrZero(objnum);
+  if (offset == 0)
+    return 0;
+
+  auto it = m_SortedOffset.find(offset);
+  if (it == m_SortedOffset.end() || ++it == m_SortedOffset.end())
+    return 0;
+
+  return *it - offset;
+}
+
+void CPDF_Parser::GetIndirectBinary(FX_DWORD objnum,
+                                    uint8_t*& pBuffer,
+                                    FX_DWORD& size) {
+  pBuffer = nullptr;
+  size = 0;
+  if (!IsValidObjectNumber(objnum))
+    return;
+
+  if (GetObjectType(objnum) == 2) {
+    CPDF_StreamAcc* pObjStream = GetObjectStream(m_ObjectInfo[objnum].pos);
+    if (!pObjStream)
+      return;
+
+    int32_t offset = GetStreamFirst(pObjStream);
+    const uint8_t* pData = pObjStream->GetData();
+    FX_DWORD totalsize = pObjStream->GetSize();
+    ScopedFileStream file(
+        FX_CreateMemoryStream((uint8_t*)pData, (size_t)totalsize, FALSE));
+
+    CPDF_SyntaxParser syntax;
+    syntax.InitParser(file.get(), 0);
+    for (int i = GetStreamNCount(pObjStream); i > 0; --i) {
+      FX_DWORD thisnum = syntax.GetDirectNum();
+      FX_DWORD thisoff = syntax.GetDirectNum();
+      if (thisnum != objnum)
+        continue;
+
+      if (i == 1) {
+        size = totalsize - (thisoff + offset);
+      } else {
+        syntax.GetDirectNum();  // Skip nextnum.
+        FX_DWORD nextoff = syntax.GetDirectNum();
+        size = nextoff - thisoff;
+      }
+
+      pBuffer = FX_Alloc(uint8_t, size);
+      FXSYS_memcpy(pBuffer, pData + thisoff + offset, size);
+      return;
+    }
+    return;
+  }
+
+  if (GetObjectType(objnum) != 1)
+    return;
+
+  FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
+  if (pos == 0)
+    return;
+
+  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+  m_pSyntax->RestorePos(pos);
+
+  bool bIsNumber;
+  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber) {
+    m_pSyntax->RestorePos(SavedPos);
+    return;
+  }
+
+  FX_DWORD parser_objnum = FXSYS_atoui(word);
+  if (parser_objnum && parser_objnum != objnum) {
+    m_pSyntax->RestorePos(SavedPos);
+    return;
+  }
+
+  word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber) {
+    m_pSyntax->RestorePos(SavedPos);
+    return;
+  }
+
+  if (m_pSyntax->GetKeyword() != "obj") {
+    m_pSyntax->RestorePos(SavedPos);
+    return;
+  }
+
+  auto it = m_SortedOffset.find(pos);
+  if (it == m_SortedOffset.end() || ++it == m_SortedOffset.end()) {
+    m_pSyntax->RestorePos(SavedPos);
+    return;
+  }
+
+  FX_FILESIZE nextoff = *it;
+  FX_BOOL bNextOffValid = FALSE;
+  if (nextoff != pos) {
+    m_pSyntax->RestorePos(nextoff);
+    word = m_pSyntax->GetNextWord(&bIsNumber);
+    if (word == "xref") {
+      bNextOffValid = TRUE;
+    } else if (bIsNumber) {
+      word = m_pSyntax->GetNextWord(&bIsNumber);
+      if (bIsNumber && m_pSyntax->GetKeyword() == "obj") {
+        bNextOffValid = TRUE;
+      }
+    }
+  }
+
+  if (!bNextOffValid) {
+    m_pSyntax->RestorePos(pos);
+    while (1) {
+      if (m_pSyntax->GetKeyword() == "endobj")
+        break;
+
+      if (m_pSyntax->SavePos() == m_pSyntax->m_FileLen)
+        break;
+    }
+    nextoff = m_pSyntax->SavePos();
+  }
+
+  size = (FX_DWORD)(nextoff - pos);
+  pBuffer = FX_Alloc(uint8_t, size);
+  m_pSyntax->RestorePos(pos);
+  m_pSyntax->ReadBlock(pBuffer, size);
+  m_pSyntax->RestorePos(SavedPos);
+}
+
+CPDF_Object* CPDF_Parser::ParseIndirectObjectAt(
+    CPDF_IndirectObjectHolder* pObjList,
+    FX_FILESIZE pos,
+    FX_DWORD objnum) {
+  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+  m_pSyntax->RestorePos(pos);
+  bool bIsNumber;
+  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber) {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  FX_FILESIZE objOffset = m_pSyntax->SavePos();
+  objOffset -= word.GetLength();
+  FX_DWORD parser_objnum = FXSYS_atoui(word);
+  if (objnum && parser_objnum != objnum) {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber) {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  FX_DWORD parser_gennum = FXSYS_atoui(word);
+  if (m_pSyntax->GetKeyword() != "obj") {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  CPDF_Object* pObj =
+      m_pSyntax->GetObject(pObjList, objnum, parser_gennum, true);
+  m_pSyntax->SavePos();
+
+  CFX_ByteString bsWord = m_pSyntax->GetKeyword();
+  if (bsWord == "endobj")
+    m_pSyntax->SavePos();
+
+  m_pSyntax->RestorePos(SavedPos);
+  if (pObj) {
+    if (!objnum)
+      pObj->m_ObjNum = parser_objnum;
+    pObj->m_GenNum = parser_gennum;
+  }
+  return pObj;
+}
+
+CPDF_Object* CPDF_Parser::ParseIndirectObjectAtByStrict(
+    CPDF_IndirectObjectHolder* pObjList,
+    FX_FILESIZE pos,
+    FX_DWORD objnum,
+    FX_FILESIZE* pResultPos) {
+  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+  m_pSyntax->RestorePos(pos);
+
+  bool bIsNumber;
+  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber) {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  FX_DWORD parser_objnum = FXSYS_atoui(word);
+  if (objnum && parser_objnum != objnum) {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber) {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  FX_DWORD gennum = FXSYS_atoui(word);
+  if (m_pSyntax->GetKeyword() != "obj") {
+    m_pSyntax->RestorePos(SavedPos);
+    return nullptr;
+  }
+
+  CPDF_Object* pObj = m_pSyntax->GetObjectByStrict(pObjList, objnum, gennum);
+  if (pResultPos)
+    *pResultPos = m_pSyntax->m_Pos;
+
+  m_pSyntax->RestorePos(SavedPos);
+  return pObj;
+}
+
+CPDF_Dictionary* CPDF_Parser::LoadTrailerV4() {
+  if (m_pSyntax->GetKeyword() != "trailer")
+    return nullptr;
+
+  std::unique_ptr<CPDF_Object, ReleaseDeleter<CPDF_Object>> pObj(
+      m_pSyntax->GetObject(m_pDocument, 0, 0, true));
+  if (!ToDictionary(pObj.get()))
+    return nullptr;
+  return pObj.release()->AsDictionary();
+}
+
+FX_DWORD CPDF_Parser::GetPermissions(FX_BOOL bCheckRevision) {
+  if (!m_pSecurityHandler)
+    return (FX_DWORD)-1;
+
+  FX_DWORD dwPermission = m_pSecurityHandler->GetPermissions();
+  if (m_pEncryptDict && m_pEncryptDict->GetStringBy("Filter") == "Standard") {
+    dwPermission &= 0xFFFFFFFC;
+    dwPermission |= 0xFFFFF0C0;
+    if (bCheckRevision && m_pEncryptDict->GetIntegerBy("R") == 2)
+      dwPermission &= 0xFFFFF0FF;
+  }
+  return dwPermission;
+}
+
+FX_BOOL CPDF_Parser::IsLinearizedFile(IFX_FileRead* pFileAccess,
+                                      FX_DWORD offset) {
+  m_pSyntax->InitParser(pFileAccess, offset);
+  m_pSyntax->RestorePos(m_pSyntax->m_HeaderOffset + 9);
+
+  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
+  bool bIsNumber;
+  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber)
+    return FALSE;
+
+  FX_DWORD objnum = FXSYS_atoui(word);
+  word = m_pSyntax->GetNextWord(&bIsNumber);
+  if (!bIsNumber)
+    return FALSE;
+
+  FX_DWORD gennum = FXSYS_atoui(word);
+  if (m_pSyntax->GetKeyword() != "obj") {
+    m_pSyntax->RestorePos(SavedPos);
+    return FALSE;
+  }
+
+  m_pLinearized = m_pSyntax->GetObject(nullptr, objnum, gennum, true);
+  if (!m_pLinearized)
+    return FALSE;
+
+  CPDF_Dictionary* pDict = m_pLinearized->GetDict();
+  if (pDict && pDict->GetElement("Linearized")) {
+    m_pSyntax->GetNextWord(nullptr);
+
+    CPDF_Object* pLen = pDict->GetElement("L");
+    if (!pLen) {
+      m_pLinearized->Release();
+      m_pLinearized = nullptr;
+      return FALSE;
+    }
+
+    if (pLen->GetInteger() != (int)pFileAccess->GetSize())
+      return FALSE;
+
+    if (CPDF_Number* pNo = ToNumber(pDict->GetElement("P")))
+      m_dwFirstPageNo = pNo->GetInteger();
+
+    if (CPDF_Number* pTable = ToNumber(pDict->GetElement("T")))
+      m_LastXRefOffset = pTable->GetInteger();
+
+    return TRUE;
+  }
+  m_pLinearized->Release();
+  m_pLinearized = nullptr;
+  return FALSE;
+}
+
+CPDF_Parser::Error CPDF_Parser::StartAsyncParse(IFX_FileRead* pFileAccess) {
+  CloseParser();
+  m_bXRefStream = FALSE;
+  m_LastXRefOffset = 0;
+  m_bOwnFileRead = true;
+
+  int32_t offset = GetHeaderOffset(pFileAccess);
+  if (offset == -1)
+    return FORMAT_ERROR;
+
+  if (!IsLinearizedFile(pFileAccess, offset)) {
+    m_pSyntax->m_pFileAccess = nullptr;
+    return StartParse(pFileAccess);
+  }
+
+  m_pDocument = new CPDF_Document(this);
+  FX_FILESIZE dwFirstXRefOffset = m_pSyntax->SavePos();
+
+  FX_BOOL bXRefRebuilt = FALSE;
+  FX_BOOL bLoadV4 = FALSE;
+  if (!(bLoadV4 = LoadCrossRefV4(dwFirstXRefOffset, 0, FALSE)) &&
+      !LoadCrossRefV5(&dwFirstXRefOffset, TRUE)) {
+    if (!RebuildCrossRef())
+      return FORMAT_ERROR;
+
+    bXRefRebuilt = TRUE;
+    m_LastXRefOffset = 0;
+  }
+
+  if (bLoadV4) {
+    m_pTrailer = LoadTrailerV4();
+    if (!m_pTrailer)
+      return SUCCESS;
+
+    int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
+    if (xrefsize > 0)
+      ShrinkObjectMap(xrefsize);
+  }
+
+  Error eRet = SetEncryptHandler();
+  if (eRet != SUCCESS)
+    return eRet;
+
+  m_pDocument->LoadAsynDoc(m_pLinearized->GetDict());
+  if (!m_pDocument->GetRoot() || m_pDocument->GetPageCount() == 0) {
+    if (bXRefRebuilt)
+      return FORMAT_ERROR;
+
+    ReleaseEncryptHandler();
+    if (!RebuildCrossRef())
+      return FORMAT_ERROR;
+
+    eRet = SetEncryptHandler();
+    if (eRet != SUCCESS)
+      return eRet;
+
+    m_pDocument->LoadAsynDoc(m_pLinearized->GetDict());
+    if (!m_pDocument->GetRoot())
+      return FORMAT_ERROR;
+  }
+
+  if (GetRootObjNum() == 0) {
+    ReleaseEncryptHandler();
+    if (!RebuildCrossRef() || GetRootObjNum() == 0)
+      return FORMAT_ERROR;
+
+    eRet = SetEncryptHandler();
+    if (eRet != SUCCESS)
+      return eRet;
+  }
+
+  if (m_pSecurityHandler && m_pSecurityHandler->IsMetadataEncrypted()) {
+    if (CPDF_Reference* pMetadata =
+            ToReference(m_pDocument->GetRoot()->GetElement("Metadata")))
+      m_pSyntax->m_MetadataObjnum = pMetadata->GetRefObjNum();
+  }
+  return SUCCESS;
+}
+
+FX_BOOL CPDF_Parser::LoadLinearizedAllCrossRefV5(FX_FILESIZE xrefpos) {
+  if (!LoadCrossRefV5(&xrefpos, FALSE))
+    return FALSE;
+
+  std::set<FX_FILESIZE> seen_xrefpos;
+  while (xrefpos) {
+    seen_xrefpos.insert(xrefpos);
+    if (!LoadCrossRefV5(&xrefpos, FALSE))
+      return FALSE;
+
+    // Check for circular references.
+    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
+      return FALSE;
+  }
+  m_ObjectStreamMap.clear();
+  m_bXRefStream = TRUE;
+  return TRUE;
+}
+
+CPDF_Parser::Error CPDF_Parser::LoadLinearizedMainXRefTable() {
+  FX_DWORD dwSaveMetadataObjnum = m_pSyntax->m_MetadataObjnum;
+  m_pSyntax->m_MetadataObjnum = 0;
+  if (m_pTrailer) {
+    m_pTrailer->Release();
+    m_pTrailer = nullptr;
+  }
+
+  m_pSyntax->RestorePos(m_LastXRefOffset - m_pSyntax->m_HeaderOffset);
+  uint8_t ch = 0;
+  FX_DWORD dwCount = 0;
+  m_pSyntax->GetNextChar(ch);
+  while (PDFCharIsWhitespace(ch)) {
+    ++dwCount;
+    if (m_pSyntax->m_FileLen >=
+        (FX_FILESIZE)(m_pSyntax->SavePos() + m_pSyntax->m_HeaderOffset)) {
+      break;
+    }
+    m_pSyntax->GetNextChar(ch);
+  }
+  m_LastXRefOffset += dwCount;
+  m_ObjectStreamMap.clear();
+  m_ObjCache.clear();
+
+  if (!LoadLinearizedAllCrossRefV4(m_LastXRefOffset, m_dwXrefStartObjNum) &&
+      !LoadLinearizedAllCrossRefV5(m_LastXRefOffset)) {
+    m_LastXRefOffset = 0;
+    m_pSyntax->m_MetadataObjnum = dwSaveMetadataObjnum;
+    return FORMAT_ERROR;
+  }
+
+  m_pSyntax->m_MetadataObjnum = dwSaveMetadataObjnum;
+  return SUCCESS;
+}
diff --git a/core/src/fpdfapi/fpdf_parser/cpdf_simple_parser.cpp b/core/src/fpdfapi/fpdf_parser/cpdf_simple_parser.cpp
new file mode 100644
index 0000000000..ad656795f2
--- /dev/null
+++ b/core/src/fpdfapi/fpdf_parser/cpdf_simple_parser.cpp
@@ -0,0 +1,170 @@
+// Copyright 2016 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/include/fpdfapi/cpdf_simple_parser.h"
+
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
+
+CPDF_SimpleParser::CPDF_SimpleParser(const uint8_t* pData, FX_DWORD dwSize)
+    : m_pData(pData), m_dwSize(dwSize), m_dwCurPos(0) {}
+
+CPDF_SimpleParser::CPDF_SimpleParser(const CFX_ByteStringC& str)
+    : m_pData(str.GetPtr()), m_dwSize(str.GetLength()), m_dwCurPos(0) {}
+
+void CPDF_SimpleParser::ParseWord(const uint8_t*& pStart, FX_DWORD& dwSize) {
+  pStart = nullptr;
+  dwSize = 0;
+  uint8_t ch;
+  while (1) {
+    if (m_dwSize <= m_dwCurPos)
+      return;
+    ch = m_pData[m_dwCurPos++];
+    while (PDFCharIsWhitespace(ch)) {
+      if (m_dwSize <= m_dwCurPos)
+        return;
+      ch = m_pData[m_dwCurPos++];
+    }
+
+    if (ch != '%')
+      break;
+
+    while (1) {
+      if (m_dwSize <= m_dwCurPos)
+        return;
+      ch = m_pData[m_dwCurPos++];
+      if (PDFCharIsLineEnding(ch))
+        break;
+    }
+  }
+
+  FX_DWORD start_pos = m_dwCurPos - 1;
+  pStart = m_pData + start_pos;
+  if (PDFCharIsDelimiter(ch)) {
+    if (ch == '/') {
+      while (1) {
+        if (m_dwSize <= m_dwCurPos)
+          return;
+        ch = m_pData[m_dwCurPos++];
+        if (!PDFCharIsOther(ch) && !PDFCharIsNumeric(ch)) {
+          m_dwCurPos--;
+          dwSize = m_dwCurPos - start_pos;
+          return;
+        }
+      }
+    } else {
+      dwSize = 1;
+      if (ch == '<') {
+        if (m_dwSize <= m_dwCurPos)
+          return;
+        ch = m_pData[m_dwCurPos++];
+        if (ch == '<')
+          dwSize = 2;
+        else
+          m_dwCurPos--;
+      } else if (ch == '>') {
+        if (m_dwSize <= m_dwCurPos)
+          return;
+        ch = m_pData[m_dwCurPos++];
+        if (ch == '>')
+          dwSize = 2;
+        else
+          m_dwCurPos--;
+      }
+    }
+    return;
+  }
+
+  dwSize = 1;
+  while (1) {
+    if (m_dwSize <= m_dwCurPos)
+      return;
+    ch = m_pData[m_dwCurPos++];
+
+    if (PDFCharIsDelimiter(ch) || PDFCharIsWhitespace(ch)) {
+      m_dwCurPos--;
+      break;
+    }
+    dwSize++;
+  }
+}
+
+CFX_ByteStringC CPDF_SimpleParser::GetWord() {
+  const uint8_t* pStart;
+  FX_DWORD dwSize;
+  ParseWord(pStart, dwSize);
+  if (dwSize == 1 && pStart[0] == '<') {
+    while (m_dwCurPos < m_dwSize && m_pData[m_dwCurPos] != '>') {
+      m_dwCurPos++;
+    }
+    if (m_dwCurPos < m_dwSize) {
+      m_dwCurPos++;
+    }
+    return CFX_ByteStringC(pStart,
+                           (FX_STRSIZE)(m_dwCurPos - (pStart - m_pData)));
+  }
+  if (dwSize == 1 && pStart[0] == '(') {
+    int level = 1;
+    while (m_dwCurPos < m_dwSize) {
+      if (m_pData[m_dwCurPos] == ')') {
+        level--;
+        if (level == 0) {
+          break;
+        }
+      }
+      if (m_pData[m_dwCurPos] == '\\') {
+        if (m_dwSize <= m_dwCurPos) {
+          break;
+        }
+        m_dwCurPos++;
+      } else if (m_pData[m_dwCurPos] == '(') {
+        level++;
+      }
+      if (m_dwSize <= m_dwCurPos) {
+        break;
+      }
+      m_dwCurPos++;
+    }
+    if (m_dwCurPos < m_dwSize) {
+      m_dwCurPos++;
+    }
+    return CFX_ByteStringC(pStart,
+                           (FX_STRSIZE)(m_dwCurPos - (pStart - m_pData)));
+  }
+  return CFX_ByteStringC(pStart, dwSize);
+}
+
+bool CPDF_SimpleParser::FindTagParamFromStart(const CFX_ByteStringC& token,
+                                              int nParams) {
+  nParams++;
+  FX_DWORD* pBuf = FX_Alloc(FX_DWORD, nParams);
+  int buf_index = 0;
+  int buf_count = 0;
+  m_dwCurPos = 0;
+  while (1) {
+    pBuf[buf_index++] = m_dwCurPos;
+    if (buf_index == nParams) {
+      buf_index = 0;
+    }
+    buf_count++;
+    if (buf_count > nParams) {
+      buf_count = nParams;
+    }
+    CFX_ByteStringC word = GetWord();
+    if (word.IsEmpty()) {
+      FX_Free(pBuf);
+      return false;
+    }
+    if (word == token) {
+      if (buf_count < nParams) {
+        continue;
+      }
+      m_dwCurPos = pBuf[buf_index];
+      FX_Free(pBuf);
+      return true;
+    }
+  }
+  return false;
+}
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility_unittest.cpp b/core/src/fpdfapi/fpdf_parser/cpdf_simple_parser_unittest.cpp
index 2eb930bef6..f95838d91f 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility_unittest.cpp
+++ b/core/src/fpdfapi/fpdf_parser/cpdf_simple_parser_unittest.cpp
@@ -2,10 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "core/include/fpdfapi/fpdf_parser.h"
+#include "core/include/fpdfapi/cpdf_simple_parser.h"
 
 #include <string>
 
+#include "core/include/fpdfapi/fpdf_parser.h"
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/test_support.h"
 
diff --git a/core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.cpp b/core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.cpp
index 3091ab108b..151139e4a4 100644
--- a/core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.cpp
+++ b/core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.cpp
@@ -11,6 +11,7 @@
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fxcrt/fx_ext.h"
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
 #include "third_party/base/numerics/safe_math.h"
 
 namespace {
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp
index 4fb471713b..473ea76e76 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp
@@ -12,6 +12,7 @@
 #include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fxcodec/fx_codec.h"
 #include "core/include/fxcrt/fx_ext.h"
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
 #include "third_party/base/stl_util.h"
 
 #define _STREAM_MAX_SIZE_ 20 * 1024 * 1024
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp
index 95907ae8fd..9fe534ec35 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp
@@ -8,6 +8,8 @@
 
 #include <time.h>
 
+#include "core/include/fpdfapi/cpdf_parser.h"
+#include "core/include/fpdfapi/cpdf_simple_parser.h"
 #include "core/include/fdrm/fx_crypt.h"
 
 const uint8_t defpasscode[32] = {
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_objects.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_objects.cpp
index bed70ebd5d..28c35c899e 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_objects.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_objects.cpp
@@ -8,6 +8,7 @@
 
 #include <algorithm>
 
+#include "core/include/fpdfapi/cpdf_parser.h"
 #include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fxcrt/fx_string.h"
 #include "third_party/base/stl_util.h"
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp
index 2b61cdc2a2..0d62e4d3ed 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp
@@ -13,68 +13,23 @@
 #include <vector>
 
 #include "core/include/fpdfapi/cpdf_document.h"
+#include "core/include/fpdfapi/cpdf_parser.h"
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fxcrt/fx_ext.h"
 #include "core/include/fxcrt/fx_safe_types.h"
 #include "core/src/fpdfapi/fpdf_page/pageint.h"
 #include "core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.h"
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
 #include "core/src/fpdfapi/fpdf_parser/parser_int.h"
 #include "third_party/base/stl_util.h"
 
 namespace {
 
-// A limit on the size of the xref table. Theoretical limits are higher, but
-// this may be large enough in practice.
-const int32_t kMaxXRefSize = 1048576;
-
-// A limit on the maximum object number in the xref table. Theoretical limits
-// are higher, but this may be large enough in practice.
-const FX_DWORD kMaxObjectNumber = 1048576;
-
-int32_t GetHeaderOffset(IFX_FileRead* pFile) {
-  // TODO(dsinclair): This is a complicated way of saying %PDF, simplify?
-  const FX_DWORD tag = FXDWORD_FROM_LSBFIRST(0x46445025);
-
-  const size_t kBufSize = 4;
-  uint8_t buf[kBufSize];
-  int32_t offset = 0;
-  while (offset <= 1024) {
-    if (!pFile->ReadBlock(buf, offset, kBufSize))
-      return -1;
-
-    if (*(FX_DWORD*)buf == tag)
-      return offset;
-
-    ++offset;
-  }
-  return -1;
-}
-
-int32_t GetDirectInteger(CPDF_Dictionary* pDict, const CFX_ByteStringC& key) {
-  CPDF_Number* pObj = ToNumber(pDict->GetElement(key));
-  return pObj ? pObj->GetInteger() : 0;
-}
-
-FX_DWORD GetVarInt(const uint8_t* p, int32_t n) {
-  FX_DWORD result = 0;
-  for (int32_t i = 0; i < n; ++i)
-    result = result * 256 + p[i];
-  return result;
-}
-
-int32_t GetStreamNCount(CPDF_StreamAcc* pObjStream) {
-  return pObjStream->GetDict()->GetIntegerBy("N");
-}
-
-int32_t GetStreamFirst(CPDF_StreamAcc* pObjStream) {
-  return pObjStream->GetDict()->GetIntegerBy("First");
-}
-
 bool CanReadFromBitStream(const CFX_BitStream* hStream,
                           const FX_SAFE_DWORD& num_bits) {
-  return (num_bits.IsValid() &&
-          hStream->BitsRemaining() >= num_bits.ValueOrDie());
+  return num_bits.IsValid() &&
+         hStream->BitsRemaining() >= num_bits.ValueOrDie();
 }
 
 }  // namespace
@@ -86,1607 +41,6 @@ bool IsSignatureDict(const CPDF_Dictionary* pDict) {
   return pType && pType->GetString() == "Sig";
 }
 
-CPDF_Parser::CPDF_Parser()
-    : m_pDocument(nullptr),
-      m_bOwnFileRead(true),
-      m_FileVersion(0),
-      m_pTrailer(nullptr),
-      m_pEncryptDict(nullptr),
-      m_pLinearized(nullptr),
-      m_dwFirstPageNo(0),
-      m_dwXrefStartObjNum(0) {
-  m_pSyntax.reset(new CPDF_SyntaxParser);
-}
-
-CPDF_Parser::~CPDF_Parser() {
-  CloseParser();
-}
-
-FX_DWORD CPDF_Parser::GetLastObjNum() const {
-  return m_ObjectInfo.empty() ? 0 : m_ObjectInfo.rbegin()->first;
-}
-
-bool CPDF_Parser::IsValidObjectNumber(FX_DWORD objnum) const {
-  return !m_ObjectInfo.empty() && objnum <= m_ObjectInfo.rbegin()->first;
-}
-
-FX_FILESIZE CPDF_Parser::GetObjectPositionOrZero(FX_DWORD objnum) const {
-  auto it = m_ObjectInfo.find(objnum);
-  return it != m_ObjectInfo.end() ? it->second.pos : 0;
-}
-
-uint8_t CPDF_Parser::GetObjectType(FX_DWORD objnum) const {
-  ASSERT(IsValidObjectNumber(objnum));
-  auto it = m_ObjectInfo.find(objnum);
-  return it != m_ObjectInfo.end() ? it->second.type : 0;
-}
-
-uint16_t CPDF_Parser::GetObjectGenNum(FX_DWORD objnum) const {
-  ASSERT(IsValidObjectNumber(objnum));
-  auto it = m_ObjectInfo.find(objnum);
-  return it != m_ObjectInfo.end() ? it->second.gennum : 0;
-}
-
-bool CPDF_Parser::IsObjectFreeOrNull(FX_DWORD objnum) const {
-  uint8_t type = GetObjectType(objnum);
-  return type == 0 || type == 255;
-}
-
-void CPDF_Parser::SetEncryptDictionary(CPDF_Dictionary* pDict) {
-  m_pEncryptDict = pDict;
-}
-
-CPDF_CryptoHandler* CPDF_Parser::GetCryptoHandler() {
-  return m_pSyntax->m_pCryptoHandler.get();
-}
-
-IFX_FileRead* CPDF_Parser::GetFileAccess() const {
-  return m_pSyntax->m_pFileAccess;
-}
-
-void CPDF_Parser::ShrinkObjectMap(FX_DWORD objnum) {
-  if (objnum == 0) {
-    m_ObjectInfo.clear();
-    return;
-  }
-
-  auto it = m_ObjectInfo.lower_bound(objnum);
-  while (it != m_ObjectInfo.end()) {
-    auto saved_it = it++;
-    m_ObjectInfo.erase(saved_it);
-  }
-
-  if (!pdfium::ContainsKey(m_ObjectInfo, objnum - 1))
-    m_ObjectInfo[objnum - 1].pos = 0;
-}
-
-void CPDF_Parser::CloseParser() {
-  m_bVersionUpdated = FALSE;
-  delete m_pDocument;
-  m_pDocument = nullptr;
-
-  if (m_pTrailer) {
-    m_pTrailer->Release();
-    m_pTrailer = nullptr;
-  }
-  ReleaseEncryptHandler();
-  SetEncryptDictionary(nullptr);
-
-  if (m_bOwnFileRead && m_pSyntax->m_pFileAccess) {
-    m_pSyntax->m_pFileAccess->Release();
-    m_pSyntax->m_pFileAccess = nullptr;
-  }
-
-  m_ObjectStreamMap.clear();
-  m_ObjCache.clear();
-  m_SortedOffset.clear();
-  m_ObjectInfo.clear();
-
-  int32_t iLen = m_Trailers.GetSize();
-  for (int32_t i = 0; i < iLen; ++i) {
-    if (CPDF_Dictionary* trailer = m_Trailers.GetAt(i))
-      trailer->Release();
-  }
-  m_Trailers.RemoveAll();
-
-  if (m_pLinearized) {
-    m_pLinearized->Release();
-    m_pLinearized = nullptr;
-  }
-}
-
-CPDF_Parser::Error CPDF_Parser::StartParse(IFX_FileRead* pFileAccess) {
-  CloseParser();
-
-  m_bXRefStream = FALSE;
-  m_LastXRefOffset = 0;
-  m_bOwnFileRead = true;
-
-  int32_t offset = GetHeaderOffset(pFileAccess);
-  if (offset == -1) {
-    if (pFileAccess)
-      pFileAccess->Release();
-    return FORMAT_ERROR;
-  }
-  m_pSyntax->InitParser(pFileAccess, offset);
-
-  uint8_t ch;
-  if (!m_pSyntax->GetCharAt(5, ch))
-    return FORMAT_ERROR;
-  if (std::isdigit(ch))
-    m_FileVersion = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch)) * 10;
-
-  if (!m_pSyntax->GetCharAt(7, ch))
-    return FORMAT_ERROR;
-  if (std::isdigit(ch))
-    m_FileVersion += FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
-
-  if (m_pSyntax->m_FileLen < m_pSyntax->m_HeaderOffset + 9)
-    return FORMAT_ERROR;
-
-  m_pSyntax->RestorePos(m_pSyntax->m_FileLen - m_pSyntax->m_HeaderOffset - 9);
-  m_pDocument = new CPDF_Document(this);
-
-  FX_BOOL bXRefRebuilt = FALSE;
-  if (m_pSyntax->SearchWord("startxref", TRUE, FALSE, 4096)) {
-    m_SortedOffset.insert(m_pSyntax->SavePos());
-    m_pSyntax->GetKeyword();
-
-    bool bNumber;
-    CFX_ByteString xrefpos_str = m_pSyntax->GetNextWord(&bNumber);
-    if (!bNumber)
-      return FORMAT_ERROR;
-
-    m_LastXRefOffset = (FX_FILESIZE)FXSYS_atoi64(xrefpos_str);
-    if (!LoadAllCrossRefV4(m_LastXRefOffset) &&
-        !LoadAllCrossRefV5(m_LastXRefOffset)) {
-      if (!RebuildCrossRef())
-        return FORMAT_ERROR;
-
-      bXRefRebuilt = TRUE;
-      m_LastXRefOffset = 0;
-    }
-  } else {
-    if (!RebuildCrossRef())
-      return FORMAT_ERROR;
-
-    bXRefRebuilt = TRUE;
-  }
-  Error eRet = SetEncryptHandler();
-  if (eRet != SUCCESS)
-    return eRet;
-
-  m_pDocument->LoadDoc();
-  if (!m_pDocument->GetRoot() || m_pDocument->GetPageCount() == 0) {
-    if (bXRefRebuilt)
-      return FORMAT_ERROR;
-
-    ReleaseEncryptHandler();
-    if (!RebuildCrossRef())
-      return FORMAT_ERROR;
-
-    eRet = SetEncryptHandler();
-    if (eRet != SUCCESS)
-      return eRet;
-
-    m_pDocument->LoadDoc();
-    if (!m_pDocument->GetRoot())
-      return FORMAT_ERROR;
-  }
-  if (GetRootObjNum() == 0) {
-    ReleaseEncryptHandler();
-    if (!RebuildCrossRef() || GetRootObjNum() == 0)
-      return FORMAT_ERROR;
-
-    eRet = SetEncryptHandler();
-    if (eRet != SUCCESS)
-      return eRet;
-  }
-  if (m_pSecurityHandler && !m_pSecurityHandler->IsMetadataEncrypted()) {
-    CPDF_Reference* pMetadata =
-        ToReference(m_pDocument->GetRoot()->GetElement("Metadata"));
-    if (pMetadata)
-      m_pSyntax->m_MetadataObjnum = pMetadata->GetRefObjNum();
-  }
-  return SUCCESS;
-}
-CPDF_Parser::Error CPDF_Parser::SetEncryptHandler() {
-  ReleaseEncryptHandler();
-  SetEncryptDictionary(nullptr);
-
-  if (!m_pTrailer)
-    return FORMAT_ERROR;
-
-  CPDF_Object* pEncryptObj = m_pTrailer->GetElement("Encrypt");
-  if (pEncryptObj) {
-    if (CPDF_Dictionary* pEncryptDict = pEncryptObj->AsDictionary()) {
-      SetEncryptDictionary(pEncryptDict);
-    } else if (CPDF_Reference* pRef = pEncryptObj->AsReference()) {
-      pEncryptObj = m_pDocument->GetIndirectObject(pRef->GetRefObjNum());
-      if (pEncryptObj)
-        SetEncryptDictionary(pEncryptObj->GetDict());
-    }
-  }
-
-  if (m_pEncryptDict) {
-    CFX_ByteString filter = m_pEncryptDict->GetStringBy("Filter");
-    std::unique_ptr<IPDF_SecurityHandler> pSecurityHandler;
-    Error err = HANDLER_ERROR;
-    if (filter == "Standard") {
-      pSecurityHandler.reset(new CPDF_StandardSecurityHandler);
-      err = PASSWORD_ERROR;
-    }
-    if (!pSecurityHandler)
-      return HANDLER_ERROR;
-
-    if (!pSecurityHandler->OnInit(this, m_pEncryptDict))
-      return err;
-
-    m_pSecurityHandler = std::move(pSecurityHandler);
-    std::unique_ptr<CPDF_CryptoHandler> pCryptoHandler(
-        m_pSecurityHandler->CreateCryptoHandler());
-    if (!pCryptoHandler->Init(m_pEncryptDict, m_pSecurityHandler.get()))
-      return HANDLER_ERROR;
-    m_pSyntax->SetEncrypt(std::move(pCryptoHandler));
-  }
-  return SUCCESS;
-}
-
-void CPDF_Parser::ReleaseEncryptHandler() {
-  m_pSyntax->m_pCryptoHandler.reset();
-  m_pSecurityHandler.reset();
-}
-
-FX_FILESIZE CPDF_Parser::GetObjectOffset(FX_DWORD objnum) const {
-  if (!IsValidObjectNumber(objnum))
-    return 0;
-
-  if (GetObjectType(objnum) == 1)
-    return GetObjectPositionOrZero(objnum);
-
-  if (GetObjectType(objnum) == 2) {
-    FX_FILESIZE pos = GetObjectPositionOrZero(objnum);
-    return GetObjectPositionOrZero(pos);
-  }
-  return 0;
-}
-
-FX_BOOL CPDF_Parser::LoadAllCrossRefV4(FX_FILESIZE xrefpos) {
-  if (!LoadCrossRefV4(xrefpos, 0, TRUE))
-    return FALSE;
-
-  m_pTrailer = LoadTrailerV4();
-  if (!m_pTrailer)
-    return FALSE;
-
-  int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
-  if (xrefsize > 0 && xrefsize <= kMaxXRefSize)
-    ShrinkObjectMap(xrefsize);
-
-  std::vector<FX_FILESIZE> CrossRefList;
-  std::vector<FX_FILESIZE> XRefStreamList;
-  std::set<FX_FILESIZE> seen_xrefpos;
-
-  CrossRefList.push_back(xrefpos);
-  XRefStreamList.push_back(GetDirectInteger(m_pTrailer, "XRefStm"));
-  seen_xrefpos.insert(xrefpos);
-
-  // When |m_pTrailer| doesn't have Prev entry or Prev entry value is not
-  // numerical, GetDirectInteger() returns 0. Loading will end.
-  xrefpos = GetDirectInteger(m_pTrailer, "Prev");
-  while (xrefpos) {
-    // Check for circular references.
-    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
-      return FALSE;
-
-    seen_xrefpos.insert(xrefpos);
-
-    // SLOW ...
-    CrossRefList.insert(CrossRefList.begin(), xrefpos);
-    LoadCrossRefV4(xrefpos, 0, TRUE);
-
-    std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
-        LoadTrailerV4());
-    if (!pDict)
-      return FALSE;
-
-    xrefpos = GetDirectInteger(pDict.get(), "Prev");
-
-    // SLOW ...
-    XRefStreamList.insert(XRefStreamList.begin(),
-                          pDict->GetIntegerBy("XRefStm"));
-    m_Trailers.Add(pDict.release());
-  }
-
-  for (size_t i = 0; i < CrossRefList.size(); ++i) {
-    if (!LoadCrossRefV4(CrossRefList[i], XRefStreamList[i], FALSE))
-      return FALSE;
-  }
-  return TRUE;
-}
-
-FX_BOOL CPDF_Parser::LoadLinearizedAllCrossRefV4(FX_FILESIZE xrefpos,
-                                                 FX_DWORD dwObjCount) {
-  if (!LoadLinearizedCrossRefV4(xrefpos, dwObjCount))
-    return FALSE;
-
-  m_pTrailer = LoadTrailerV4();
-  if (!m_pTrailer)
-    return FALSE;
-
-  int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
-  if (xrefsize == 0)
-    return FALSE;
-
-  std::vector<FX_FILESIZE> CrossRefList;
-  std::vector<FX_FILESIZE> XRefStreamList;
-  std::set<FX_FILESIZE> seen_xrefpos;
-
-  CrossRefList.push_back(xrefpos);
-  XRefStreamList.push_back(GetDirectInteger(m_pTrailer, "XRefStm"));
-  seen_xrefpos.insert(xrefpos);
-
-  xrefpos = GetDirectInteger(m_pTrailer, "Prev");
-  while (xrefpos) {
-    // Check for circular references.
-    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
-      return FALSE;
-
-    seen_xrefpos.insert(xrefpos);
-
-    // SLOW ...
-    CrossRefList.insert(CrossRefList.begin(), xrefpos);
-    LoadCrossRefV4(xrefpos, 0, TRUE);
-
-    std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
-        LoadTrailerV4());
-    if (!pDict)
-      return FALSE;
-
-    xrefpos = GetDirectInteger(pDict.get(), "Prev");
-
-    // SLOW ...
-    XRefStreamList.insert(XRefStreamList.begin(),
-                          pDict->GetIntegerBy("XRefStm"));
-    m_Trailers.Add(pDict.release());
-  }
-
-  for (size_t i = 1; i < CrossRefList.size(); ++i) {
-    if (!LoadCrossRefV4(CrossRefList[i], XRefStreamList[i], FALSE))
-      return FALSE;
-  }
-  return TRUE;
-}
-
-FX_BOOL CPDF_Parser::LoadLinearizedCrossRefV4(FX_FILESIZE pos,
-                                              FX_DWORD dwObjCount) {
-  FX_FILESIZE dwStartPos = pos - m_pSyntax->m_HeaderOffset;
-
-  m_pSyntax->RestorePos(dwStartPos);
-  m_SortedOffset.insert(pos);
-
-  FX_DWORD start_objnum = 0;
-  FX_DWORD count = dwObjCount;
-  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
-
-  const int32_t recordsize = 20;
-  std::vector<char> buf(1024 * recordsize + 1);
-  buf[1024 * recordsize] = '\0';
-
-  int32_t nBlocks = count / 1024 + 1;
-  for (int32_t block = 0; block < nBlocks; block++) {
-    int32_t block_size = block == nBlocks - 1 ? count % 1024 : 1024;
-    FX_DWORD dwReadSize = block_size * recordsize;
-    if ((FX_FILESIZE)(dwStartPos + dwReadSize) > m_pSyntax->m_FileLen)
-      return FALSE;
-
-    if (!m_pSyntax->ReadBlock(reinterpret_cast<uint8_t*>(buf.data()),
-                              dwReadSize)) {
-      return FALSE;
-    }
-
-    for (int32_t i = 0; i < block_size; i++) {
-      FX_DWORD objnum = start_objnum + block * 1024 + i;
-      char* pEntry = &buf[i * recordsize];
-      if (pEntry[17] == 'f') {
-        m_ObjectInfo[objnum].pos = 0;
-        m_ObjectInfo[objnum].type = 0;
-      } else {
-        int32_t offset = FXSYS_atoi(pEntry);
-        if (offset == 0) {
-          for (int32_t c = 0; c < 10; c++) {
-            if (!std::isdigit(pEntry[c]))
-              return FALSE;
-          }
-        }
-
-        m_ObjectInfo[objnum].pos = offset;
-        int32_t version = FXSYS_atoi(pEntry + 11);
-        if (version >= 1)
-          m_bVersionUpdated = TRUE;
-
-        m_ObjectInfo[objnum].gennum = version;
-        if (m_ObjectInfo[objnum].pos < m_pSyntax->m_FileLen)
-          m_SortedOffset.insert(m_ObjectInfo[objnum].pos);
-
-        m_ObjectInfo[objnum].type = 1;
-      }
-    }
-  }
-  m_pSyntax->RestorePos(SavedPos + count * recordsize);
-  return TRUE;
-}
-
-bool CPDF_Parser::LoadCrossRefV4(FX_FILESIZE pos,
-                                 FX_FILESIZE streampos,
-                                 FX_BOOL bSkip) {
-  m_pSyntax->RestorePos(pos);
-  if (m_pSyntax->GetKeyword() != "xref")
-    return false;
-
-  m_SortedOffset.insert(pos);
-  if (streampos)
-    m_SortedOffset.insert(streampos);
-
-  while (1) {
-    FX_FILESIZE SavedPos = m_pSyntax->SavePos();
-    bool bIsNumber;
-    CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
-    if (word.IsEmpty())
-      return false;
-
-    if (!bIsNumber) {
-      m_pSyntax->RestorePos(SavedPos);
-      break;
-    }
-
-    FX_DWORD start_objnum = FXSYS_atoui(word);
-    if (start_objnum >= kMaxObjectNumber)
-      return false;
-
-    FX_DWORD count = m_pSyntax->GetDirectNum();
-    m_pSyntax->ToNextWord();
-    SavedPos = m_pSyntax->SavePos();
-    const int32_t recordsize = 20;
-
-    m_dwXrefStartObjNum = start_objnum;
-    if (!bSkip) {
-      std::vector<char> buf(1024 * recordsize + 1);
-      buf[1024 * recordsize] = '\0';
-
-      int32_t nBlocks = count / 1024 + 1;
-      for (int32_t block = 0; block < nBlocks; block++) {
-        int32_t block_size = block == nBlocks - 1 ? count % 1024 : 1024;
-        m_pSyntax->ReadBlock(reinterpret_cast<uint8_t*>(buf.data()),
-                             block_size * recordsize);
-
-        for (int32_t i = 0; i < block_size; i++) {
-          FX_DWORD objnum = start_objnum + block * 1024 + i;
-          char* pEntry = &buf[i * recordsize];
-          if (pEntry[17] == 'f') {
-            m_ObjectInfo[objnum].pos = 0;
-            m_ObjectInfo[objnum].type = 0;
-          } else {
-            FX_FILESIZE offset = (FX_FILESIZE)FXSYS_atoi64(pEntry);
-            if (offset == 0) {
-              for (int32_t c = 0; c < 10; c++) {
-                if (!std::isdigit(pEntry[c]))
-                  return false;
-              }
-            }
-
-            m_ObjectInfo[objnum].pos = offset;
-            int32_t version = FXSYS_atoi(pEntry + 11);
-            if (version >= 1)
-              m_bVersionUpdated = TRUE;
-
-            m_ObjectInfo[objnum].gennum = version;
-            if (m_ObjectInfo[objnum].pos < m_pSyntax->m_FileLen)
-              m_SortedOffset.insert(m_ObjectInfo[objnum].pos);
-
-            m_ObjectInfo[objnum].type = 1;
-          }
-        }
-      }
-    }
-    m_pSyntax->RestorePos(SavedPos + count * recordsize);
-  }
-  return !streampos || LoadCrossRefV5(&streampos, FALSE);
-}
-
-FX_BOOL CPDF_Parser::LoadAllCrossRefV5(FX_FILESIZE xrefpos) {
-  if (!LoadCrossRefV5(&xrefpos, TRUE))
-    return FALSE;
-
-  std::set<FX_FILESIZE> seen_xrefpos;
-  while (xrefpos) {
-    seen_xrefpos.insert(xrefpos);
-    if (!LoadCrossRefV5(&xrefpos, FALSE))
-      return FALSE;
-
-    // Check for circular references.
-    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
-      return FALSE;
-  }
-  m_ObjectStreamMap.clear();
-  m_bXRefStream = TRUE;
-  return TRUE;
-}
-
-FX_BOOL CPDF_Parser::RebuildCrossRef() {
-  m_ObjectInfo.clear();
-  m_SortedOffset.clear();
-  if (m_pTrailer) {
-    m_pTrailer->Release();
-    m_pTrailer = nullptr;
-  }
-
-  ParserState state = ParserState::kDefault;
-
-  int32_t inside_index = 0;
-  FX_DWORD objnum = 0;
-  FX_DWORD gennum = 0;
-  int32_t depth = 0;
-
-  const FX_DWORD kBufferSize = 4096;
-  std::vector<uint8_t> buffer(kBufferSize);
-
-  FX_FILESIZE pos = m_pSyntax->m_HeaderOffset;
-  FX_FILESIZE start_pos = 0;
-  FX_FILESIZE start_pos1 = 0;
-  FX_FILESIZE last_obj = -1;
-  FX_FILESIZE last_xref = -1;
-  FX_FILESIZE last_trailer = -1;
-
-  while (pos < m_pSyntax->m_FileLen) {
-    const FX_FILESIZE saved_pos = pos;
-    bool bOverFlow = false;
-    FX_DWORD size =
-        std::min((FX_DWORD)(m_pSyntax->m_FileLen - pos), kBufferSize);
-    if (!m_pSyntax->m_pFileAccess->ReadBlock(buffer.data(), pos, size))
-      break;
-
-    for (FX_DWORD i = 0; i < size; i++) {
-      uint8_t byte = buffer[i];
-      switch (state) {
-        case ParserState::kDefault:
-          if (PDFCharIsWhitespace(byte)) {
-            state = ParserState::kWhitespace;
-          } else if (std::isdigit(byte)) {
-            --i;
-            state = ParserState::kWhitespace;
-          } else if (byte == '%') {
-            inside_index = 0;
-            state = ParserState::kComment;
-          } else if (byte == '(') {
-            state = ParserState::kString;
-            depth = 1;
-          } else if (byte == '<') {
-            inside_index = 1;
-            state = ParserState::kHexString;
-          } else if (byte == '\\') {
-            state = ParserState::kEscapedString;
-          } else if (byte == 't') {
-            state = ParserState::kTrailer;
-            inside_index = 1;
-          }
-          break;
-
-        case ParserState::kWhitespace:
-          if (std::isdigit(byte)) {
-            start_pos = pos + i;
-            state = ParserState::kObjNum;
-            objnum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
-          } else if (byte == 't') {
-            state = ParserState::kTrailer;
-            inside_index = 1;
-          } else if (byte == 'x') {
-            state = ParserState::kXref;
-            inside_index = 1;
-          } else if (!PDFCharIsWhitespace(byte)) {
-            --i;
-            state = ParserState::kDefault;
-          }
-          break;
-
-        case ParserState::kObjNum:
-          if (std::isdigit(byte)) {
-            objnum =
-                objnum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
-          } else if (PDFCharIsWhitespace(byte)) {
-            state = ParserState::kPostObjNum;
-          } else {
-            --i;
-            state = ParserState::kEndObj;
-            inside_index = 0;
-          }
-          break;
-
-        case ParserState::kPostObjNum:
-          if (std::isdigit(byte)) {
-            start_pos1 = pos + i;
-            state = ParserState::kGenNum;
-            gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
-          } else if (byte == 't') {
-            state = ParserState::kTrailer;
-            inside_index = 1;
-          } else if (!PDFCharIsWhitespace(byte)) {
-            --i;
-            state = ParserState::kDefault;
-          }
-          break;
-
-        case ParserState::kGenNum:
-          if (std::isdigit(byte)) {
-            gennum =
-                gennum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
-          } else if (PDFCharIsWhitespace(byte)) {
-            state = ParserState::kPostGenNum;
-          } else {
-            --i;
-            state = ParserState::kDefault;
-          }
-          break;
-
-        case ParserState::kPostGenNum:
-          if (byte == 'o') {
-            state = ParserState::kBeginObj;
-            inside_index = 1;
-          } else if (std::isdigit(byte)) {
-            objnum = gennum;
-            gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
-            start_pos = start_pos1;
-            start_pos1 = pos + i;
-            state = ParserState::kGenNum;
-          } else if (byte == 't') {
-            state = ParserState::kTrailer;
-            inside_index = 1;
-          } else if (!PDFCharIsWhitespace(byte)) {
-            --i;
-            state = ParserState::kDefault;
-          }
-          break;
-
-        case ParserState::kBeginObj:
-          switch (inside_index) {
-            case 1:
-              if (byte != 'b') {
-                --i;
-                state = ParserState::kDefault;
-              } else {
-                inside_index++;
-              }
-              break;
-            case 2:
-              if (byte != 'j') {
-                --i;
-                state = ParserState::kDefault;
-              } else {
-                inside_index++;
-              }
-              break;
-            case 3:
-              if (PDFCharIsWhitespace(byte) || PDFCharIsDelimiter(byte)) {
-                FX_FILESIZE obj_pos = start_pos - m_pSyntax->m_HeaderOffset;
-                m_SortedOffset.insert(obj_pos);
-                last_obj = start_pos;
-                FX_FILESIZE obj_end = 0;
-                CPDF_Object* pObject = ParseIndirectObjectAtByStrict(
-                    m_pDocument, obj_pos, objnum, &obj_end);
-                if (CPDF_Stream* pStream = ToStream(pObject)) {
-                  if (CPDF_Dictionary* pDict = pStream->GetDict()) {
-                    if ((pDict->KeyExist("Type")) &&
-                        (pDict->GetStringBy("Type") == "XRef" &&
-                         pDict->KeyExist("Size"))) {
-                      CPDF_Object* pRoot = pDict->GetElement("Root");
-                      if (pRoot && pRoot->GetDict() &&
-                          pRoot->GetDict()->GetElement("Pages")) {
-                        if (m_pTrailer)
-                          m_pTrailer->Release();
-                        m_pTrailer = ToDictionary(pDict->Clone());
-                      }
-                    }
-                  }
-                }
-
-                FX_FILESIZE offset = 0;
-                m_pSyntax->RestorePos(obj_pos);
-                offset = m_pSyntax->FindTag("obj", 0);
-                if (offset == -1)
-                  offset = 0;
-                else
-                  offset += 3;
-
-                FX_FILESIZE nLen = obj_end - obj_pos - offset;
-                if ((FX_DWORD)nLen > size - i) {
-                  pos = obj_end + m_pSyntax->m_HeaderOffset;
-                  bOverFlow = true;
-                } else {
-                  i += (FX_DWORD)nLen;
-                }
-
-                if (!m_ObjectInfo.empty() && IsValidObjectNumber(objnum) &&
-                    m_ObjectInfo[objnum].pos) {
-                  if (pObject) {
-                    FX_DWORD oldgen = GetObjectGenNum(objnum);
-                    m_ObjectInfo[objnum].pos = obj_pos;
-                    m_ObjectInfo[objnum].gennum = gennum;
-                    if (oldgen != gennum)
-                      m_bVersionUpdated = TRUE;
-                  }
-                } else {
-                  m_ObjectInfo[objnum].pos = obj_pos;
-                  m_ObjectInfo[objnum].type = 1;
-                  m_ObjectInfo[objnum].gennum = gennum;
-                }
-
-                if (pObject)
-                  pObject->Release();
-              }
-              --i;
-              state = ParserState::kDefault;
-              break;
-          }
-          break;
-
-        case ParserState::kTrailer:
-          if (inside_index == 7) {
-            if (PDFCharIsWhitespace(byte) || PDFCharIsDelimiter(byte)) {
-              last_trailer = pos + i - 7;
-              m_pSyntax->RestorePos(pos + i - m_pSyntax->m_HeaderOffset);
-
-              CPDF_Object* pObj = m_pSyntax->GetObject(m_pDocument, 0, 0, true);
-              if (pObj) {
-                if (!pObj->IsDictionary() && !pObj->AsStream()) {
-                  pObj->Release();
-                } else {
-                  CPDF_Stream* pStream = pObj->AsStream();
-                  if (CPDF_Dictionary* pTrailer =
-                          pStream ? pStream->GetDict() : pObj->AsDictionary()) {
-                    if (m_pTrailer) {
-                      CPDF_Object* pRoot = pTrailer->GetElement("Root");
-                      CPDF_Reference* pRef = ToReference(pRoot);
-                      if (!pRoot ||
-                          (pRef && IsValidObjectNumber(pRef->GetRefObjNum()) &&
-                           m_ObjectInfo[pRef->GetRefObjNum()].pos != 0)) {
-                        auto it = pTrailer->begin();
-                        while (it != pTrailer->end()) {
-                          const CFX_ByteString& key = it->first;
-                          CPDF_Object* pElement = it->second;
-                          ++it;
-                          FX_DWORD dwObjNum =
-                              pElement ? pElement->GetObjNum() : 0;
-                          if (dwObjNum) {
-                            m_pTrailer->SetAtReference(key, m_pDocument,
-                                                       dwObjNum);
-                          } else {
-                            m_pTrailer->SetAt(key, pElement->Clone());
-                          }
-                        }
-                      }
-                      pObj->Release();
-                    } else {
-                      if (pObj->IsStream()) {
-                        m_pTrailer = ToDictionary(pTrailer->Clone());
-                        pObj->Release();
-                      } else {
-                        m_pTrailer = pTrailer;
-                      }
-
-                      FX_FILESIZE dwSavePos = m_pSyntax->SavePos();
-                      CFX_ByteString strWord = m_pSyntax->GetKeyword();
-                      if (!strWord.Compare("startxref")) {
-                        bool bNumber;
-                        CFX_ByteString bsOffset =
-                            m_pSyntax->GetNextWord(&bNumber);
-                        if (bNumber)
-                          m_LastXRefOffset = FXSYS_atoi(bsOffset);
-                      }
-                      m_pSyntax->RestorePos(dwSavePos);
-                    }
-                  } else {
-                    pObj->Release();
-                  }
-                }
-              }
-            }
-            --i;
-            state = ParserState::kDefault;
-          } else if (byte == "trailer"[inside_index]) {
-            inside_index++;
-          } else {
-            --i;
-            state = ParserState::kDefault;
-          }
-          break;
-
-        case ParserState::kXref:
-          if (inside_index == 4) {
-            last_xref = pos + i - 4;
-            state = ParserState::kWhitespace;
-          } else if (byte == "xref"[inside_index]) {
-            inside_index++;
-          } else {
-            --i;
-            state = ParserState::kDefault;
-          }
-          break;
-
-        case ParserState::kComment:
-          if (byte == '\r' || byte == '\n')
-            state = ParserState::kDefault;
-          break;
-
-        case ParserState::kString:
-          if (byte == ')') {
-            if (depth > 0)
-              depth--;
-          } else if (byte == '(') {
-            depth++;
-          }
-
-          if (!depth)
-            state = ParserState::kDefault;
-          break;
-
-        case ParserState::kHexString:
-          if (byte == '>' || (byte == '<' && inside_index == 1))
-            state = ParserState::kDefault;
-          inside_index = 0;
-          break;
-
-        case ParserState::kEscapedString:
-          if (PDFCharIsDelimiter(byte) || PDFCharIsWhitespace(byte)) {
-            --i;
-            state = ParserState::kDefault;
-          }
-          break;
-
-        case ParserState::kEndObj:
-          if (PDFCharIsWhitespace(byte)) {
-            state = ParserState::kDefault;
-          } else if (byte == '%' || byte == '(' || byte == '<' ||
-                     byte == '\\') {
-            state = ParserState::kDefault;
-            --i;
-          } else if (inside_index == 6) {
-            state = ParserState::kDefault;
-            --i;
-          } else if (byte == "endobj"[inside_index]) {
-            inside_index++;
-          }
-          break;
-      }
-
-      if (bOverFlow) {
-        size = 0;
-        break;
-      }
-    }
-    pos += size;
-
-    // If the position has not changed at all in a loop iteration, then break
-    // out to prevent infinite looping.
-    if (pos == saved_pos)
-      break;
-  }
-
-  if (last_xref != -1 && last_xref > last_obj)
-    last_trailer = last_xref;
-  else if (last_trailer == -1 || last_xref < last_obj)
-    last_trailer = m_pSyntax->m_FileLen;
-
-  m_SortedOffset.insert(last_trailer - m_pSyntax->m_HeaderOffset);
-  return m_pTrailer && !m_ObjectInfo.empty();
-}
-
-FX_BOOL CPDF_Parser::LoadCrossRefV5(FX_FILESIZE* pos, FX_BOOL bMainXRef) {
-  CPDF_Object* pObject = ParseIndirectObjectAt(m_pDocument, *pos, 0);
-  if (!pObject)
-    return FALSE;
-
-  if (m_pDocument) {
-    FX_BOOL bInserted = FALSE;
-    CPDF_Dictionary* pDict = m_pDocument->GetRoot();
-    if (!pDict || pDict->GetObjNum() != pObject->m_ObjNum) {
-      bInserted = m_pDocument->InsertIndirectObject(pObject->m_ObjNum, pObject);
-    } else {
-      if (pObject->IsStream())
-        pObject->Release();
-    }
-
-    if (!bInserted)
-      return FALSE;
-  }
-
-  CPDF_Stream* pStream = pObject->AsStream();
-  if (!pStream)
-    return FALSE;
-
-  *pos = pStream->GetDict()->GetIntegerBy("Prev");
-  int32_t size = pStream->GetDict()->GetIntegerBy("Size");
-  if (size < 0) {
-    pStream->Release();
-    return FALSE;
-  }
-
-  if (bMainXRef) {
-    m_pTrailer = ToDictionary(pStream->GetDict()->Clone());
-    ShrinkObjectMap(size);
-    for (auto& it : m_ObjectInfo)
-      it.second.type = 0;
-  } else {
-    m_Trailers.Add(ToDictionary(pStream->GetDict()->Clone()));
-  }
-
-  std::vector<std::pair<int32_t, int32_t> > arrIndex;
-  CPDF_Array* pArray = pStream->GetDict()->GetArrayBy("Index");
-  if (pArray) {
-    FX_DWORD nPairSize = pArray->GetCount() / 2;
-    for (FX_DWORD i = 0; i < nPairSize; i++) {
-      CPDF_Object* pStartNumObj = pArray->GetElement(i * 2);
-      CPDF_Object* pCountObj = pArray->GetElement(i * 2 + 1);
-
-      if (ToNumber(pStartNumObj) && ToNumber(pCountObj)) {
-        int nStartNum = pStartNumObj->GetInteger();
-        int nCount = pCountObj->GetInteger();
-        if (nStartNum >= 0 && nCount > 0)
-          arrIndex.push_back(std::make_pair(nStartNum, nCount));
-      }
-    }
-  }
-
-  if (arrIndex.size() == 0)
-    arrIndex.push_back(std::make_pair(0, size));
-
-  pArray = pStream->GetDict()->GetArrayBy("W");
-  if (!pArray) {
-    pStream->Release();
-    return FALSE;
-  }
-
-  CFX_DWordArray WidthArray;
-  FX_SAFE_DWORD dwAccWidth = 0;
-  for (FX_DWORD i = 0; i < pArray->GetCount(); i++) {
-    WidthArray.Add(pArray->GetIntegerAt(i));
-    dwAccWidth += WidthArray[i];
-  }
-
-  if (!dwAccWidth.IsValid() || WidthArray.GetSize() < 3) {
-    pStream->Release();
-    return FALSE;
-  }
-
-  FX_DWORD totalWidth = dwAccWidth.ValueOrDie();
-  CPDF_StreamAcc acc;
-  acc.LoadAllData(pStream);
-
-  const uint8_t* pData = acc.GetData();
-  FX_DWORD dwTotalSize = acc.GetSize();
-  FX_DWORD segindex = 0;
-  for (FX_DWORD i = 0; i < arrIndex.size(); i++) {
-    int32_t startnum = arrIndex[i].first;
-    if (startnum < 0)
-      continue;
-
-    m_dwXrefStartObjNum =
-        pdfium::base::checked_cast<FX_DWORD, int32_t>(startnum);
-    FX_DWORD count =
-        pdfium::base::checked_cast<FX_DWORD, int32_t>(arrIndex[i].second);
-    FX_SAFE_DWORD dwCaculatedSize = segindex;
-    dwCaculatedSize += count;
-    dwCaculatedSize *= totalWidth;
-    if (!dwCaculatedSize.IsValid() ||
-        dwCaculatedSize.ValueOrDie() > dwTotalSize) {
-      continue;
-    }
-
-    const uint8_t* segstart = pData + segindex * totalWidth;
-    FX_SAFE_DWORD dwMaxObjNum = startnum;
-    dwMaxObjNum += count;
-    FX_DWORD dwV5Size = m_ObjectInfo.empty() ? 0 : GetLastObjNum() + 1;
-    if (!dwMaxObjNum.IsValid() || dwMaxObjNum.ValueOrDie() > dwV5Size)
-      continue;
-
-    for (FX_DWORD j = 0; j < count; j++) {
-      int32_t type = 1;
-      const uint8_t* entrystart = segstart + j * totalWidth;
-      if (WidthArray[0])
-        type = GetVarInt(entrystart, WidthArray[0]);
-
-      if (GetObjectType(startnum + j) == 255) {
-        FX_FILESIZE offset =
-            GetVarInt(entrystart + WidthArray[0], WidthArray[1]);
-        m_ObjectInfo[startnum + j].pos = offset;
-        m_SortedOffset.insert(offset);
-        continue;
-      }
-
-      if (GetObjectType(startnum + j))
-        continue;
-
-      m_ObjectInfo[startnum + j].type = type;
-      if (type == 0) {
-        m_ObjectInfo[startnum + j].pos = 0;
-      } else {
-        FX_FILESIZE offset =
-            GetVarInt(entrystart + WidthArray[0], WidthArray[1]);
-        m_ObjectInfo[startnum + j].pos = offset;
-        if (type == 1) {
-          m_SortedOffset.insert(offset);
-        } else {
-          if (offset < 0 || !IsValidObjectNumber(offset)) {
-            pStream->Release();
-            return FALSE;
-          }
-          m_ObjectInfo[offset].type = 255;
-        }
-      }
-    }
-    segindex += count;
-  }
-  pStream->Release();
-  return TRUE;
-}
-
-CPDF_Array* CPDF_Parser::GetIDArray() {
-  CPDF_Object* pID = m_pTrailer ? m_pTrailer->GetElement("ID") : nullptr;
-  if (!pID)
-    return nullptr;
-
-  if (CPDF_Reference* pRef = pID->AsReference()) {
-    pID = ParseIndirectObject(nullptr, pRef->GetRefObjNum());
-    m_pTrailer->SetAt("ID", pID);
-  }
-  return ToArray(pID);
-}
-
-FX_DWORD CPDF_Parser::GetRootObjNum() {
-  CPDF_Reference* pRef =
-      ToReference(m_pTrailer ? m_pTrailer->GetElement("Root") : nullptr);
-  return pRef ? pRef->GetRefObjNum() : 0;
-}
-
-FX_DWORD CPDF_Parser::GetInfoObjNum() {
-  CPDF_Reference* pRef =
-      ToReference(m_pTrailer ? m_pTrailer->GetElement("Info") : nullptr);
-  return pRef ? pRef->GetRefObjNum() : 0;
-}
-
-FX_BOOL CPDF_Parser::IsFormStream(FX_DWORD objnum, FX_BOOL& bForm) {
-  bForm = FALSE;
-  if (!IsValidObjectNumber(objnum))
-    return TRUE;
-
-  if (GetObjectType(objnum) == 0)
-    return TRUE;
-
-  if (GetObjectType(objnum) == 2)
-    return TRUE;
-
-  FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
-  auto it = m_SortedOffset.find(pos);
-  if (it == m_SortedOffset.end())
-    return TRUE;
-
-  if (++it == m_SortedOffset.end())
-    return FALSE;
-
-  FX_FILESIZE size = *it - pos;
-  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
-  m_pSyntax->RestorePos(pos);
-
-  const char kFormStream[] = "/Form\0stream";
-  const CFX_ByteStringC kFormStreamStr(kFormStream, sizeof(kFormStream) - 1);
-  bForm = m_pSyntax->SearchMultiWord(kFormStreamStr, TRUE, size) == 0;
-  m_pSyntax->RestorePos(SavedPos);
-  return TRUE;
-}
-
-CPDF_Object* CPDF_Parser::ParseIndirectObject(
-    CPDF_IndirectObjectHolder* pObjList,
-    FX_DWORD objnum) {
-  if (!IsValidObjectNumber(objnum))
-    return nullptr;
-
-  // Prevent circular parsing the same object.
-  if (pdfium::ContainsKey(m_ParsingObjNums, objnum))
-    return nullptr;
-  ScopedSetInsertion<FX_DWORD> local_insert(&m_ParsingObjNums, objnum);
-
-  if (GetObjectType(objnum) == 1 || GetObjectType(objnum) == 255) {
-    FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
-    if (pos <= 0)
-      return nullptr;
-    return ParseIndirectObjectAt(pObjList, pos, objnum);
-  }
-  if (GetObjectType(objnum) != 2)
-    return nullptr;
-
-  CPDF_StreamAcc* pObjStream = GetObjectStream(m_ObjectInfo[objnum].pos);
-  if (!pObjStream)
-    return nullptr;
-
-  ScopedFileStream file(FX_CreateMemoryStream(
-      (uint8_t*)pObjStream->GetData(), (size_t)pObjStream->GetSize(), FALSE));
-  CPDF_SyntaxParser syntax;
-  syntax.InitParser(file.get(), 0);
-  const int32_t offset = GetStreamFirst(pObjStream);
-
-  // Read object numbers from |pObjStream| into a cache.
-  if (!pdfium::ContainsKey(m_ObjCache, pObjStream)) {
-    for (int32_t i = GetStreamNCount(pObjStream); i > 0; --i) {
-      FX_DWORD thisnum = syntax.GetDirectNum();
-      FX_DWORD thisoff = syntax.GetDirectNum();
-      m_ObjCache[pObjStream][thisnum] = thisoff;
-    }
-  }
-
-  const auto it = m_ObjCache[pObjStream].find(objnum);
-  if (it == m_ObjCache[pObjStream].end())
-    return nullptr;
-
-  syntax.RestorePos(offset + it->second);
-  return syntax.GetObject(pObjList, 0, 0, true);
-}
-
-CPDF_StreamAcc* CPDF_Parser::GetObjectStream(FX_DWORD objnum) {
-  auto it = m_ObjectStreamMap.find(objnum);
-  if (it != m_ObjectStreamMap.end())
-    return it->second.get();
-
-  if (!m_pDocument)
-    return nullptr;
-
-  const CPDF_Stream* pStream = ToStream(m_pDocument->GetIndirectObject(objnum));
-  if (!pStream)
-    return nullptr;
-
-  CPDF_StreamAcc* pStreamAcc = new CPDF_StreamAcc;
-  pStreamAcc->LoadAllData(pStream);
-  m_ObjectStreamMap[objnum].reset(pStreamAcc);
-  return pStreamAcc;
-}
-
-FX_FILESIZE CPDF_Parser::GetObjectSize(FX_DWORD objnum) const {
-  if (!IsValidObjectNumber(objnum))
-    return 0;
-
-  if (GetObjectType(objnum) == 2)
-    objnum = GetObjectPositionOrZero(objnum);
-
-  if (GetObjectType(objnum) != 1 && GetObjectType(objnum) != 255)
-    return 0;
-
-  FX_FILESIZE offset = GetObjectPositionOrZero(objnum);
-  if (offset == 0)
-    return 0;
-
-  auto it = m_SortedOffset.find(offset);
-  if (it == m_SortedOffset.end() || ++it == m_SortedOffset.end())
-    return 0;
-
-  return *it - offset;
-}
-
-void CPDF_Parser::GetIndirectBinary(FX_DWORD objnum,
-                                    uint8_t*& pBuffer,
-                                    FX_DWORD& size) {
-  pBuffer = nullptr;
-  size = 0;
-  if (!IsValidObjectNumber(objnum))
-    return;
-
-  if (GetObjectType(objnum) == 2) {
-    CPDF_StreamAcc* pObjStream = GetObjectStream(m_ObjectInfo[objnum].pos);
-    if (!pObjStream)
-      return;
-
-    int32_t offset = GetStreamFirst(pObjStream);
-    const uint8_t* pData = pObjStream->GetData();
-    FX_DWORD totalsize = pObjStream->GetSize();
-    ScopedFileStream file(
-        FX_CreateMemoryStream((uint8_t*)pData, (size_t)totalsize, FALSE));
-
-    CPDF_SyntaxParser syntax;
-    syntax.InitParser(file.get(), 0);
-    for (int i = GetStreamNCount(pObjStream); i > 0; --i) {
-      FX_DWORD thisnum = syntax.GetDirectNum();
-      FX_DWORD thisoff = syntax.GetDirectNum();
-      if (thisnum != objnum)
-        continue;
-
-      if (i == 1) {
-        size = totalsize - (thisoff + offset);
-      } else {
-        syntax.GetDirectNum();  // Skip nextnum.
-        FX_DWORD nextoff = syntax.GetDirectNum();
-        size = nextoff - thisoff;
-      }
-
-      pBuffer = FX_Alloc(uint8_t, size);
-      FXSYS_memcpy(pBuffer, pData + thisoff + offset, size);
-      return;
-    }
-    return;
-  }
-
-  if (GetObjectType(objnum) != 1)
-    return;
-
-  FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
-  if (pos == 0)
-    return;
-
-  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
-  m_pSyntax->RestorePos(pos);
-
-  bool bIsNumber;
-  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber) {
-    m_pSyntax->RestorePos(SavedPos);
-    return;
-  }
-
-  FX_DWORD parser_objnum = FXSYS_atoui(word);
-  if (parser_objnum && parser_objnum != objnum) {
-    m_pSyntax->RestorePos(SavedPos);
-    return;
-  }
-
-  word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber) {
-    m_pSyntax->RestorePos(SavedPos);
-    return;
-  }
-
-  if (m_pSyntax->GetKeyword() != "obj") {
-    m_pSyntax->RestorePos(SavedPos);
-    return;
-  }
-
-  auto it = m_SortedOffset.find(pos);
-  if (it == m_SortedOffset.end() || ++it == m_SortedOffset.end()) {
-    m_pSyntax->RestorePos(SavedPos);
-    return;
-  }
-
-  FX_FILESIZE nextoff = *it;
-  FX_BOOL bNextOffValid = FALSE;
-  if (nextoff != pos) {
-    m_pSyntax->RestorePos(nextoff);
-    word = m_pSyntax->GetNextWord(&bIsNumber);
-    if (word == "xref") {
-      bNextOffValid = TRUE;
-    } else if (bIsNumber) {
-      word = m_pSyntax->GetNextWord(&bIsNumber);
-      if (bIsNumber && m_pSyntax->GetKeyword() == "obj") {
-        bNextOffValid = TRUE;
-      }
-    }
-  }
-
-  if (!bNextOffValid) {
-    m_pSyntax->RestorePos(pos);
-    while (1) {
-      if (m_pSyntax->GetKeyword() == "endobj")
-        break;
-
-      if (m_pSyntax->SavePos() == m_pSyntax->m_FileLen)
-        break;
-    }
-    nextoff = m_pSyntax->SavePos();
-  }
-
-  size = (FX_DWORD)(nextoff - pos);
-  pBuffer = FX_Alloc(uint8_t, size);
-  m_pSyntax->RestorePos(pos);
-  m_pSyntax->ReadBlock(pBuffer, size);
-  m_pSyntax->RestorePos(SavedPos);
-}
-
-CPDF_Object* CPDF_Parser::ParseIndirectObjectAt(
-    CPDF_IndirectObjectHolder* pObjList,
-    FX_FILESIZE pos,
-    FX_DWORD objnum) {
-  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
-  m_pSyntax->RestorePos(pos);
-  bool bIsNumber;
-  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber) {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  FX_FILESIZE objOffset = m_pSyntax->SavePos();
-  objOffset -= word.GetLength();
-  FX_DWORD parser_objnum = FXSYS_atoui(word);
-  if (objnum && parser_objnum != objnum) {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber) {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  FX_DWORD parser_gennum = FXSYS_atoui(word);
-  if (m_pSyntax->GetKeyword() != "obj") {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  CPDF_Object* pObj =
-      m_pSyntax->GetObject(pObjList, objnum, parser_gennum, true);
-  m_pSyntax->SavePos();
-
-  CFX_ByteString bsWord = m_pSyntax->GetKeyword();
-  if (bsWord == "endobj")
-    m_pSyntax->SavePos();
-
-  m_pSyntax->RestorePos(SavedPos);
-  if (pObj) {
-    if (!objnum)
-      pObj->m_ObjNum = parser_objnum;
-    pObj->m_GenNum = parser_gennum;
-  }
-  return pObj;
-}
-
-CPDF_Object* CPDF_Parser::ParseIndirectObjectAtByStrict(
-    CPDF_IndirectObjectHolder* pObjList,
-    FX_FILESIZE pos,
-    FX_DWORD objnum,
-    FX_FILESIZE* pResultPos) {
-  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
-  m_pSyntax->RestorePos(pos);
-
-  bool bIsNumber;
-  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber) {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  FX_DWORD parser_objnum = FXSYS_atoui(word);
-  if (objnum && parser_objnum != objnum) {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber) {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  FX_DWORD gennum = FXSYS_atoui(word);
-  if (m_pSyntax->GetKeyword() != "obj") {
-    m_pSyntax->RestorePos(SavedPos);
-    return nullptr;
-  }
-
-  CPDF_Object* pObj = m_pSyntax->GetObjectByStrict(pObjList, objnum, gennum);
-  if (pResultPos)
-    *pResultPos = m_pSyntax->m_Pos;
-
-  m_pSyntax->RestorePos(SavedPos);
-  return pObj;
-}
-
-CPDF_Dictionary* CPDF_Parser::LoadTrailerV4() {
-  if (m_pSyntax->GetKeyword() != "trailer")
-    return nullptr;
-
-  std::unique_ptr<CPDF_Object, ReleaseDeleter<CPDF_Object>> pObj(
-      m_pSyntax->GetObject(m_pDocument, 0, 0, true));
-  if (!ToDictionary(pObj.get()))
-    return nullptr;
-  return pObj.release()->AsDictionary();
-}
-
-FX_DWORD CPDF_Parser::GetPermissions(FX_BOOL bCheckRevision) {
-  if (!m_pSecurityHandler)
-    return (FX_DWORD)-1;
-
-  FX_DWORD dwPermission = m_pSecurityHandler->GetPermissions();
-  if (m_pEncryptDict && m_pEncryptDict->GetStringBy("Filter") == "Standard") {
-    dwPermission &= 0xFFFFFFFC;
-    dwPermission |= 0xFFFFF0C0;
-    if (bCheckRevision && m_pEncryptDict->GetIntegerBy("R") == 2)
-      dwPermission &= 0xFFFFF0FF;
-  }
-  return dwPermission;
-}
-
-FX_BOOL CPDF_Parser::IsLinearizedFile(IFX_FileRead* pFileAccess,
-                                      FX_DWORD offset) {
-  m_pSyntax->InitParser(pFileAccess, offset);
-  m_pSyntax->RestorePos(m_pSyntax->m_HeaderOffset + 9);
-
-  FX_FILESIZE SavedPos = m_pSyntax->SavePos();
-  bool bIsNumber;
-  CFX_ByteString word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber)
-    return FALSE;
-
-  FX_DWORD objnum = FXSYS_atoui(word);
-  word = m_pSyntax->GetNextWord(&bIsNumber);
-  if (!bIsNumber)
-    return FALSE;
-
-  FX_DWORD gennum = FXSYS_atoui(word);
-  if (m_pSyntax->GetKeyword() != "obj") {
-    m_pSyntax->RestorePos(SavedPos);
-    return FALSE;
-  }
-
-  m_pLinearized = m_pSyntax->GetObject(nullptr, objnum, gennum, true);
-  if (!m_pLinearized)
-    return FALSE;
-
-  CPDF_Dictionary* pDict = m_pLinearized->GetDict();
-  if (pDict && pDict->GetElement("Linearized")) {
-    m_pSyntax->GetNextWord(nullptr);
-
-    CPDF_Object* pLen = pDict->GetElement("L");
-    if (!pLen) {
-      m_pLinearized->Release();
-      m_pLinearized = nullptr;
-      return FALSE;
-    }
-
-    if (pLen->GetInteger() != (int)pFileAccess->GetSize())
-      return FALSE;
-
-    if (CPDF_Number* pNo = ToNumber(pDict->GetElement("P")))
-      m_dwFirstPageNo = pNo->GetInteger();
-
-    if (CPDF_Number* pTable = ToNumber(pDict->GetElement("T")))
-      m_LastXRefOffset = pTable->GetInteger();
-
-    return TRUE;
-  }
-  m_pLinearized->Release();
-  m_pLinearized = nullptr;
-  return FALSE;
-}
-
-CPDF_Parser::Error CPDF_Parser::StartAsyncParse(IFX_FileRead* pFileAccess) {
-  CloseParser();
-  m_bXRefStream = FALSE;
-  m_LastXRefOffset = 0;
-  m_bOwnFileRead = true;
-
-  int32_t offset = GetHeaderOffset(pFileAccess);
-  if (offset == -1)
-    return FORMAT_ERROR;
-
-  if (!IsLinearizedFile(pFileAccess, offset)) {
-    m_pSyntax->m_pFileAccess = nullptr;
-    return StartParse(pFileAccess);
-  }
-
-  m_pDocument = new CPDF_Document(this);
-  FX_FILESIZE dwFirstXRefOffset = m_pSyntax->SavePos();
-
-  FX_BOOL bXRefRebuilt = FALSE;
-  FX_BOOL bLoadV4 = FALSE;
-  if (!(bLoadV4 = LoadCrossRefV4(dwFirstXRefOffset, 0, FALSE)) &&
-      !LoadCrossRefV5(&dwFirstXRefOffset, TRUE)) {
-    if (!RebuildCrossRef())
-      return FORMAT_ERROR;
-
-    bXRefRebuilt = TRUE;
-    m_LastXRefOffset = 0;
-  }
-
-  if (bLoadV4) {
-    m_pTrailer = LoadTrailerV4();
-    if (!m_pTrailer)
-      return SUCCESS;
-
-    int32_t xrefsize = GetDirectInteger(m_pTrailer, "Size");
-    if (xrefsize > 0)
-      ShrinkObjectMap(xrefsize);
-  }
-
-  Error eRet = SetEncryptHandler();
-  if (eRet != SUCCESS)
-    return eRet;
-
-  m_pDocument->LoadAsynDoc(m_pLinearized->GetDict());
-  if (!m_pDocument->GetRoot() || m_pDocument->GetPageCount() == 0) {
-    if (bXRefRebuilt)
-      return FORMAT_ERROR;
-
-    ReleaseEncryptHandler();
-    if (!RebuildCrossRef())
-      return FORMAT_ERROR;
-
-    eRet = SetEncryptHandler();
-    if (eRet != SUCCESS)
-      return eRet;
-
-    m_pDocument->LoadAsynDoc(m_pLinearized->GetDict());
-    if (!m_pDocument->GetRoot())
-      return FORMAT_ERROR;
-  }
-
-  if (GetRootObjNum() == 0) {
-    ReleaseEncryptHandler();
-    if (!RebuildCrossRef() || GetRootObjNum() == 0)
-      return FORMAT_ERROR;
-
-    eRet = SetEncryptHandler();
-    if (eRet != SUCCESS)
-      return eRet;
-  }
-
-  if (m_pSecurityHandler && m_pSecurityHandler->IsMetadataEncrypted()) {
-    if (CPDF_Reference* pMetadata =
-            ToReference(m_pDocument->GetRoot()->GetElement("Metadata")))
-      m_pSyntax->m_MetadataObjnum = pMetadata->GetRefObjNum();
-  }
-  return SUCCESS;
-}
-
-FX_BOOL CPDF_Parser::LoadLinearizedAllCrossRefV5(FX_FILESIZE xrefpos) {
-  if (!LoadCrossRefV5(&xrefpos, FALSE))
-    return FALSE;
-
-  std::set<FX_FILESIZE> seen_xrefpos;
-  while (xrefpos) {
-    seen_xrefpos.insert(xrefpos);
-    if (!LoadCrossRefV5(&xrefpos, FALSE))
-      return FALSE;
-
-    // Check for circular references.
-    if (pdfium::ContainsKey(seen_xrefpos, xrefpos))
-      return FALSE;
-  }
-  m_ObjectStreamMap.clear();
-  m_bXRefStream = TRUE;
-  return TRUE;
-}
-
-CPDF_Parser::Error CPDF_Parser::LoadLinearizedMainXRefTable() {
-  FX_DWORD dwSaveMetadataObjnum = m_pSyntax->m_MetadataObjnum;
-  m_pSyntax->m_MetadataObjnum = 0;
-  if (m_pTrailer) {
-    m_pTrailer->Release();
-    m_pTrailer = nullptr;
-  }
-
-  m_pSyntax->RestorePos(m_LastXRefOffset - m_pSyntax->m_HeaderOffset);
-  uint8_t ch = 0;
-  FX_DWORD dwCount = 0;
-  m_pSyntax->GetNextChar(ch);
-  while (PDFCharIsWhitespace(ch)) {
-    ++dwCount;
-    if (m_pSyntax->m_FileLen >=
-        (FX_FILESIZE)(m_pSyntax->SavePos() + m_pSyntax->m_HeaderOffset)) {
-      break;
-    }
-    m_pSyntax->GetNextChar(ch);
-  }
-  m_LastXRefOffset += dwCount;
-  m_ObjectStreamMap.clear();
-  m_ObjCache.clear();
-
-  if (!LoadLinearizedAllCrossRefV4(m_LastXRefOffset, m_dwXrefStartObjNum) &&
-      !LoadLinearizedAllCrossRefV5(m_LastXRefOffset)) {
-    m_LastXRefOffset = 0;
-    m_pSyntax->m_MetadataObjnum = dwSaveMetadataObjnum;
-    return FORMAT_ERROR;
-  }
-
-  m_pSyntax->m_MetadataObjnum = dwSaveMetadataObjnum;
-  return SUCCESS;
-}
-
 
 class CPDF_DataAvail final : public IPDF_DataAvail {
  public:
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp
index 68068cb522..c8e1ceec0b 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp
@@ -5,6 +5,7 @@
 #include <limits>
 #include <string>
 
+#include "core/include/fpdfapi/cpdf_parser.h"
 #include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fxcrt/fx_stream.h"
 #include "core/src/fpdfapi/fpdf_parser/cpdf_syntax_parser.h"
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.cpp
index 37b82dd564..a08cf7d466 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.cpp
@@ -4,8 +4,9 @@
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
-#include "core/include/fpdfapi/fpdf_parser.h"
+#include "core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h"
 
+#include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fxcrt/fx_ext.h"
 
 // Indexed by 8-bit character code, contains either:
@@ -60,171 +61,28 @@ const char PDF_CharType[256] = {
     'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R', 'R',
     'R', 'R', 'R', 'R', 'R', 'R', 'R', 'W'};
 
-CPDF_SimpleParser::CPDF_SimpleParser(const uint8_t* pData, FX_DWORD dwSize) {
-  m_pData = pData;
-  m_dwSize = dwSize;
-  m_dwCurPos = 0;
-}
-
-CPDF_SimpleParser::CPDF_SimpleParser(const CFX_ByteStringC& str) {
-  m_pData = str.GetPtr();
-  m_dwSize = str.GetLength();
-  m_dwCurPos = 0;
-}
+int32_t GetHeaderOffset(IFX_FileRead* pFile) {
+  // TODO(dsinclair): This is a complicated way of saying %PDF, simplify?
+  const FX_DWORD tag = FXDWORD_FROM_LSBFIRST(0x46445025);
 
-void CPDF_SimpleParser::ParseWord(const uint8_t*& pStart, FX_DWORD& dwSize) {
-  pStart = NULL;
-  dwSize = 0;
-  uint8_t ch;
-  while (1) {
-    if (m_dwSize <= m_dwCurPos)
-      return;
-    ch = m_pData[m_dwCurPos++];
-    while (PDFCharIsWhitespace(ch)) {
-      if (m_dwSize <= m_dwCurPos)
-        return;
-      ch = m_pData[m_dwCurPos++];
-    }
+  const size_t kBufSize = 4;
+  uint8_t buf[kBufSize];
+  int32_t offset = 0;
+  while (offset <= 1024) {
+    if (!pFile->ReadBlock(buf, offset, kBufSize))
+      return -1;
 
-    if (ch != '%')
-      break;
-
-    while (1) {
-      if (m_dwSize <= m_dwCurPos)
-        return;
-      ch = m_pData[m_dwCurPos++];
-      if (ch == '\r' || ch == '\n')
-        break;
-    }
-  }
+    if (*(FX_DWORD*)buf == tag)
+      return offset;
 
-  FX_DWORD start_pos = m_dwCurPos - 1;
-  pStart = m_pData + start_pos;
-  if (PDFCharIsDelimiter(ch)) {
-    if (ch == '/') {
-      while (1) {
-        if (m_dwSize <= m_dwCurPos)
-          return;
-        ch = m_pData[m_dwCurPos++];
-        if (!PDFCharIsOther(ch) && !PDFCharIsNumeric(ch)) {
-          m_dwCurPos--;
-          dwSize = m_dwCurPos - start_pos;
-          return;
-        }
-      }
-    } else {
-      dwSize = 1;
-      if (ch == '<') {
-        if (m_dwSize <= m_dwCurPos)
-          return;
-        ch = m_pData[m_dwCurPos++];
-        if (ch == '<')
-          dwSize = 2;
-        else
-          m_dwCurPos--;
-      } else if (ch == '>') {
-        if (m_dwSize <= m_dwCurPos)
-          return;
-        ch = m_pData[m_dwCurPos++];
-        if (ch == '>')
-          dwSize = 2;
-        else
-          m_dwCurPos--;
-      }
-    }
-    return;
-  }
-
-  dwSize = 1;
-  while (1) {
-    if (m_dwSize <= m_dwCurPos)
-      return;
-    ch = m_pData[m_dwCurPos++];
-
-    if (PDFCharIsDelimiter(ch) || PDFCharIsWhitespace(ch)) {
-      m_dwCurPos--;
-      break;
-    }
-    dwSize++;
+    ++offset;
   }
+  return -1;
 }
 
-CFX_ByteStringC CPDF_SimpleParser::GetWord() {
-  const uint8_t* pStart;
-  FX_DWORD dwSize;
-  ParseWord(pStart, dwSize);
-  if (dwSize == 1 && pStart[0] == '<') {
-    while (m_dwCurPos < m_dwSize && m_pData[m_dwCurPos] != '>') {
-      m_dwCurPos++;
-    }
-    if (m_dwCurPos < m_dwSize) {
-      m_dwCurPos++;
-    }
-    return CFX_ByteStringC(pStart,
-                           (FX_STRSIZE)(m_dwCurPos - (pStart - m_pData)));
-  }
-  if (dwSize == 1 && pStart[0] == '(') {
-    int level = 1;
-    while (m_dwCurPos < m_dwSize) {
-      if (m_pData[m_dwCurPos] == ')') {
-        level--;
-        if (level == 0) {
-          break;
-        }
-      }
-      if (m_pData[m_dwCurPos] == '\\') {
-        if (m_dwSize <= m_dwCurPos) {
-          break;
-        }
-        m_dwCurPos++;
-      } else if (m_pData[m_dwCurPos] == '(') {
-        level++;
-      }
-      if (m_dwSize <= m_dwCurPos) {
-        break;
-      }
-      m_dwCurPos++;
-    }
-    if (m_dwCurPos < m_dwSize) {
-      m_dwCurPos++;
-    }
-    return CFX_ByteStringC(pStart,
-                           (FX_STRSIZE)(m_dwCurPos - (pStart - m_pData)));
-  }
-  return CFX_ByteStringC(pStart, dwSize);
-}
-
-bool CPDF_SimpleParser::FindTagParamFromStart(const CFX_ByteStringC& token,
-                                              int nParams) {
-  nParams++;
-  FX_DWORD* pBuf = FX_Alloc(FX_DWORD, nParams);
-  int buf_index = 0;
-  int buf_count = 0;
-  m_dwCurPos = 0;
-  while (1) {
-    pBuf[buf_index++] = m_dwCurPos;
-    if (buf_index == nParams) {
-      buf_index = 0;
-    }
-    buf_count++;
-    if (buf_count > nParams) {
-      buf_count = nParams;
-    }
-    CFX_ByteStringC word = GetWord();
-    if (word.IsEmpty()) {
-      FX_Free(pBuf);
-      return false;
-    }
-    if (word == token) {
-      if (buf_count < nParams) {
-        continue;
-      }
-      m_dwCurPos = pBuf[buf_index];
-      FX_Free(pBuf);
-      return true;
-    }
-  }
-  return false;
+int32_t GetDirectInteger(CPDF_Dictionary* pDict, const CFX_ByteStringC& key) {
+  CPDF_Number* pObj = ToNumber(pDict->GetElement(key));
+  return pObj ? pObj->GetInteger() : 0;
 }
 
 CFX_ByteString PDF_NameDecode(const CFX_ByteStringC& bstr) {
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h b/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h
new file mode 100644
index 0000000000..cdc1199623
--- /dev/null
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_utility.h
@@ -0,0 +1,39 @@
+// Copyright 2016 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_SRC_FPDFAPI_FPDF_PARSER_FPDF_PARSER_UTILITY_H_
+#define CORE_SRC_FPDFAPI_FPDF_PARSER_FPDF_PARSER_UTILITY_H_
+
+#include "core/include/fxcrt/fx_string.h"
+#include "core/include/fxcrt/fx_system.h"
+
+class IFX_FileRead;
+class CPDF_Dictionary;
+
+// Use the accessors below instead of directly accessing PDF_CharType.
+extern const char PDF_CharType[256];
+
+inline bool PDFCharIsWhitespace(uint8_t c) {
+  return PDF_CharType[c] == 'W';
+}
+inline bool PDFCharIsNumeric(uint8_t c) {
+  return PDF_CharType[c] == 'N';
+}
+inline bool PDFCharIsDelimiter(uint8_t c) {
+  return PDF_CharType[c] == 'D';
+}
+inline bool PDFCharIsOther(uint8_t c) {
+  return PDF_CharType[c] == 'R';
+}
+
+inline bool PDFCharIsLineEnding(uint8_t c) {
+  return c == '\r' || c == '\n';
+}
+
+int32_t GetHeaderOffset(IFX_FileRead* pFile);
+int32_t GetDirectInteger(CPDF_Dictionary* pDict, const CFX_ByteStringC& key);
+
+#endif  // CORE_SRC_FPDFAPI_FPDF_PARSER_FPDF_PARSER_UTILITY_H_