Make more CPDF_Parser method const.

core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp

 // Copyright 2014 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 "parser_int.h"
 
 #include <memory>
 #include <set>
@@ skipping 118 matching lines @@
   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;
 }
 
 void CPDF_Parser::SetEncryptDictionary(CPDF_Dictionary* pDict) {
   m_pEncryptDict = pDict;
 }
+
+FX_FILESIZE CPDF_Parser::GetObjectPositionOrZero(FX_DWORD objnum) const {
+  auto it = m_ObjectInfo.find(objnum);
+  return it != m_ObjectInfo.end() ? it->second.pos : 0;
+}
+
 void CPDF_Parser::CloseParser(FX_BOOL bReParse) {
   m_bVersionUpdated = FALSE;
   if (!bReParse) {
     delete m_pDocument;
     m_pDocument = NULL;
   }
   if (m_pTrailer) {
     m_pTrailer->Release();
     m_pTrailer = NULL;
   }
@@ skipping 187 matching lines @@
     m_Syntax.SetEncrypt(pCryptoHandler.release());
   }
   return PDFPARSE_ERROR_SUCCESS;
 }
 void CPDF_Parser::ReleaseEncryptHandler() {
   m_Syntax.m_pCryptoHandler.reset();
   if (!m_bForceUseSecurityHandler) {
     m_pSecurityHandler.reset();
   }
 }
-FX_FILESIZE CPDF_Parser::GetObjectOffset(FX_DWORD objnum) {
+
+FX_FILESIZE CPDF_Parser::GetObjectOffset(FX_DWORD objnum) const {
   if (!IsValidObjectNumber(objnum))
     return 0;
 
   if (m_V5Type[objnum] == 1)
-    return m_ObjectInfo[objnum].pos;
+    return GetObjectPositionOrZero(objnum);
 
   if (m_V5Type[objnum] == 2) {
-    FX_FILESIZE pos = m_ObjectInfo[objnum].pos;
-    return m_ObjectInfo[pos].pos;
+    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) {
@@ skipping 861 matching lines @@
   const CPDF_Stream* pStream =
       ToStream(m_pDocument ? m_pDocument->GetIndirectObject(objnum) : nullptr);
   if (!pStream)
     return nullptr;
 
   pStreamAcc = new CPDF_StreamAcc;
   pStreamAcc->LoadAllData(pStream);
   m_ObjectStreamMap.SetAt((void*)(uintptr_t)objnum, pStreamAcc);
   return pStreamAcc;
 }
-FX_FILESIZE CPDF_Parser::GetObjectSize(FX_DWORD objnum) {
+
+FX_FILESIZE CPDF_Parser::GetObjectSize(FX_DWORD objnum) const {
   if (!IsValidObjectNumber(objnum))
     return 0;
 
-  if (m_V5Type[objnum] == 2) {
-    objnum = m_ObjectInfo[objnum].pos;
-  }
+  if (m_V5Type[objnum] == 2)
+    objnum = GetObjectPositionOrZero(objnum);
+
   if (m_V5Type[objnum] == 1 || m_V5Type[objnum] == 255) {
-    FX_FILESIZE offset = m_ObjectInfo[objnum].pos;
-    if (offset == 0) {
+    FX_FILESIZE offset = GetObjectPositionOrZero(objnum);
+    if (offset == 0)
       return 0;
-    }
-    void* pResult = FXSYS_bsearch(&offset, m_SortedOffset.GetData(),
-                                  m_SortedOffset.GetSize(), sizeof(FX_FILESIZE),
-                                  CompareFileSize);
-    if (!pResult) {
+
+    FX_FILESIZE* pResult = static_cast<FX_FILESIZE*>(FXSYS_bsearch(
+        &offset, m_SortedOffset.GetData(), m_SortedOffset.GetSize(),
+        sizeof(FX_FILESIZE), CompareFileSize));
+    if (!pResult)
       return 0;
-    }
-    if ((FX_FILESIZE*)pResult - (FX_FILESIZE*)m_SortedOffset.GetData() ==
-        m_SortedOffset.GetSize() - 1) {
+
+    if (pResult - m_SortedOffset.GetData() == m_SortedOffset.GetSize() - 1)
       return 0;
-    }
-    return ((FX_FILESIZE*)pResult)[1] - offset;
+
+    return pResult[1] - offset;
   }
   return 0;
 }
+
 void CPDF_Parser::GetIndirectBinary(FX_DWORD objnum,
                                     uint8_t*& pBuffer,
                                     FX_DWORD& size) {
   pBuffer = NULL;
   size = 0;
   if (!IsValidObjectNumber(objnum))
     return;
 
   if (m_V5Type[objnum] == 2) {
     CPDF_StreamAcc* pObjStream = GetObjectStream(m_ObjectInfo[objnum].pos);
@@ skipping 415 matching lines @@
 
 CPDF_SyntaxParser::CPDF_SyntaxParser() {
   m_pFileAccess = NULL;
   m_pFileBuf = NULL;
   m_BufSize = CPDF_ModuleMgr::kFileBufSize;
   m_pFileBuf = NULL;
   m_MetadataObjnum = 0;
   m_dwWordPos = 0;
   m_bFileStream = FALSE;
 }
+
 CPDF_SyntaxParser::~CPDF_SyntaxParser() {
   FX_Free(m_pFileBuf);
 }
 
 FX_BOOL CPDF_SyntaxParser::GetCharAt(FX_FILESIZE pos, uint8_t& ch) {
   CFX_AutoRestorer<FX_FILESIZE> save_pos(&m_Pos);
   m_Pos = pos;
   return GetNextChar(ch);
 }
 
@@ skipping 54 matching lines @@
   ch = m_pFileBuf[pos - m_BufOffset];
   return TRUE;
 }
 FX_BOOL CPDF_SyntaxParser::ReadBlock(uint8_t* pBuf, FX_DWORD size) {
   if (!m_pFileAccess->ReadBlock(pBuf, m_Pos + m_HeaderOffset, size)) {
     return FALSE;
   }
   m_Pos += size;
   return TRUE;
 }
-#define MAX_WORD_BUFFER 256
+
 void CPDF_SyntaxParser::GetNextWord() {
   m_WordSize = 0;
   m_bIsNumber = TRUE;
   uint8_t ch;
   if (!GetNextChar(ch)) {
     return;
   }
   while (1) {
     while (PDFCharIsWhitespace(ch)) {
       if (!GetNextChar(ch))
@@ skipping 16 matching lines @@
     if (ch == '/') {
       while (1) {
         if (!GetNextChar(ch))
           return;
 
         if (!PDFCharIsOther(ch) && !PDFCharIsNumeric(ch)) {
           m_Pos--;
           return;
         }
 
-        if (m_WordSize < MAX_WORD_BUFFER)
+        if (m_WordSize < sizeof(m_WordBuffer) - 1)
           m_WordBuffer[m_WordSize++] = ch;
       }
     } else if (ch == '<') {
       if (!GetNextChar(ch))
         return;
       if (ch == '<')
         m_WordBuffer[m_WordSize++] = ch;
       else
         m_Pos--;
     } else if (ch == '>') {
       if (!GetNextChar(ch))
         return;
       if (ch == '>')
         m_WordBuffer[m_WordSize++] = ch;
       else
         m_Pos--;
     }
     return;
   }
 
   while (1) {
-    if (m_WordSize < MAX_WORD_BUFFER)
+    if (m_WordSize < sizeof(m_WordBuffer) - 1)
       m_WordBuffer[m_WordSize++] = ch;
 
     if (!PDFCharIsNumeric(ch))
       m_bIsNumber = FALSE;
     if (!GetNextChar(ch))
       return;
 
     if (PDFCharIsDelimiter(ch) || PDFCharIsWhitespace(ch)) {
       m_Pos--;
       break;
@@ skipping 1928 matching lines @@
     }
     pObj->Release();
     return -1;
   }
   pHints->AddSegment(m_Pos, req_size);
   return 0;
 }
 inline void CPDF_DataAvail::SetStartOffset(FX_FILESIZE dwOffset) {
   m_Pos = dwOffset;
 }
-#define MAX_WORD_BUFFER 256
+
 FX_BOOL CPDF_DataAvail::GetNextToken(CFX_ByteString& token) {
   m_WordSize = 0;
   uint8_t ch;
   if (!GetNextChar(ch))
     return FALSE;
 
   while (1) {
     while (PDFCharIsWhitespace(ch)) {
       if (!GetNextChar(ch))
         return FALSE;
@@ skipping 17 matching lines @@
         if (!GetNextChar(ch))
           return FALSE;
 
         if (!PDFCharIsOther(ch) && !PDFCharIsNumeric(ch)) {
           m_Pos--;
           CFX_ByteString ret(m_WordBuffer, m_WordSize);
           token = ret;
           return TRUE;
         }
 
-        if (m_WordSize < MAX_WORD_BUFFER)
+        if (m_WordSize < sizeof(m_WordBuffer) - 1)

[Wei Li, 2016/01/04 20:11:48]

Should be "m_WordSize < sizeof(m_WordBuffer)"?

[Lei Zhang, 2016/01/05 01:27:53]

That's because |CPDF_DataAvail::m_WordBuffer| is defined as "uint8_t
m_WordBuffer[257];". Slightly confusingly, there's also
|CPDF_SyntaxParser::m_WordBuffer|.

I made this one a local variable and changed its size to 256.

For the CPDF_SyntaxParser version, it may need the extra byte at the end for a
NUL in CPDF_SyntaxParser::GetDirectNum(), so I'm leaving it as is.

           m_WordBuffer[m_WordSize++] = ch;
       }
     } else if (ch == '<') {
       if (!GetNextChar(ch))
         return FALSE;
 
       if (ch == '<')
         m_WordBuffer[m_WordSize++] = ch;
       else
         m_Pos--;
     } else if (ch == '>') {
       if (!GetNextChar(ch))
         return FALSE;
 
       if (ch == '>')
         m_WordBuffer[m_WordSize++] = ch;
       else
         m_Pos--;
     }
 
     CFX_ByteString ret(m_WordBuffer, m_WordSize);
     token = ret;
     return TRUE;
   }
 
   while (1) {
-    if (m_WordSize < MAX_WORD_BUFFER)
+    if (m_WordSize < sizeof(m_WordBuffer) - 1)

[Wei Li, 2016/01/04 20:11:48]

Ditto

       m_WordBuffer[m_WordSize++] = ch;
 
     if (!GetNextChar(ch))
       return FALSE;
 
     if (PDFCharIsDelimiter(ch) || PDFCharIsWhitespace(ch)) {
       m_Pos--;
       break;
     }
   }
@@ skipping 1131 matching lines @@
   if (!m_pLinearizedDict)
     return -1;
   CPDF_Array* pRange = m_pLinearizedDict->GetArray("H");
   if (!pRange)
     return -1;
   CPDF_Object* pStreamLen = pRange->GetElementValue(1);
   if (!pStreamLen)
     return -1;
   return pStreamLen->GetInteger();
 }