std::unique_ptr<CPDF_Object> CPDF_DataAvail::ParseIndirectObjectAt(
FX_FILESIZE pos,
uint32_t objnum,
CPDF_IndirectObjectHolder* pObjList) {
FX_FILESIZE SavedPos = m_syntaxParser.SavePos();
m_syntaxParser.RestorePos(pos);
bool bIsNumber;
CFX_ByteString word = m_syntaxParser.GetNextWord(&bIsNumber);
if (!bIsNumber)
return nullptr;
uint32_t parser_objnum = FXSYS_atoui(word.c_str());
if (objnum && parser_objnum != objnum)
return nullptr;
word = m_syntaxParser.GetNextWord(&bIsNumber);
if (!bIsNumber)
return nullptr;
uint32_t gennum = FXSYS_atoui(word.c_str());
if (m_syntaxParser.GetKeyword() != "obj") {
m_syntaxParser.RestorePos(SavedPos);
return nullptr;
}
std::unique_ptr<CPDF_Object> pObj =
m_syntaxParser.GetObject(pObjList, parser_objnum, gennum, true);
m_syntaxParser.RestorePos(SavedPos);
return pObj;
}
bool CPDF_DataAvail::IsLinearizedFile(uint8_t* pData, uint32_t dwLen) {
if (m_pLinearized)
return true;
ScopedFileStream file(FX_CreateMemoryStream(pData, (size_t)dwLen, false));
int32_t offset = GetHeaderOffset(file.get());
if (offset == -1) {
m_docStatus = PDF_DATAAVAIL_ERROR;
return false;
}
m_dwHeaderOffset = offset;
m_syntaxParser.InitParser(file.get(), offset);
m_syntaxParser.RestorePos(m_syntaxParser.m_HeaderOffset + 9);
bool bNumber;
CFX_ByteString wordObjNum = m_syntaxParser.GetNextWord(&bNumber);
if (!bNumber)
return false;
uint32_t objnum = FXSYS_atoui(wordObjNum.c_str());
m_pLinearized = CPDF_LinearizedHeader::CreateForObject(
ParseIndirectObjectAt(m_syntaxParser.m_HeaderOffset + 9, objnum));
if (!m_pLinearized ||
m_pLinearized->GetFileSize() != m_pFileRead->GetSize()) {
m_pLinearized.reset();
return false;
}
return true;
}
int32_t CPDF_DataAvail::CheckCrossRefStream(DownloadHints* pHints,
FX_FILESIZE& xref_offset) {
xref_offset = 0;
uint32_t req_size =
(uint32_t)(m_Pos + 512 > m_dwFileLen ? m_dwFileLen - m_Pos : 512);
if (m_pFileAvail->IsDataAvail(m_Pos, req_size)) {
int32_t iSize = (int32_t)(m_Pos + req_size - m_dwCurrentXRefSteam);
CFX_BinaryBuf buf(iSize);
uint8_t* pBuf = buf.GetBuffer();
m_pFileRead->ReadBlock(pBuf, m_dwCurrentXRefSteam, iSize);
ScopedFileStream file(FX_CreateMemoryStream(pBuf, (size_t)iSize, false));
m_parser.m_pSyntax->InitParser(file.get(), 0);
bool bNumber;
CFX_ByteString objnum = m_parser.m_pSyntax->GetNextWord(&bNumber);
if (!bNumber)
return -1;
uint32_t objNum = FXSYS_atoui(objnum.c_str());
std::unique_ptr<CPDF_Object> pObj =
m_parser.ParseIndirectObjectAt(nullptr, 0, objNum);
if (!pObj) {
m_Pos += m_parser.m_pSyntax->SavePos();
return 0;
}
CPDF_Dictionary* pDict = pObj->GetDict();
CPDF_Name* pName = ToName(pDict ? pDict->GetObjectFor("Type") : nullptr);
if (pName && pName->GetString() == "XRef") {
m_Pos += m_parser.m_pSyntax->SavePos();
xref_offset = pObj->GetDict()->GetIntegerFor("Prev");
return 1;
}
return -1;
}
pHints->AddSegment(m_Pos, req_size);
return 0;
}
void CFDF_Document::ParseStream(IFX_FileRead* pFile, FX_BOOL bOwnFile) {
m_pFile = pFile;
m_bOwnFile = bOwnFile;
CPDF_SyntaxParser parser;
parser.InitParser(m_pFile, 0);
while (1) {
bool bNumber;
CFX_ByteString word = parser.GetNextWord(&bNumber);
if (bNumber) {
uint32_t objnum = FXSYS_atoui(word.c_str());
word = parser.GetNextWord(&bNumber);
if (!bNumber)
break;
word = parser.GetNextWord(nullptr);
if (word != "obj")
break;
CPDF_Object* pObj = parser.GetObject(this, objnum, 0, true);
if (!pObj)
break;
ReplaceIndirectObjectIfHigherGeneration(objnum, pObj);
word = parser.GetNextWord(nullptr);
if (word != "endobj")
break;
} else {
if (word != "trailer")
break;
if (CPDF_Dictionary* pMainDict =
ToDictionary(parser.GetObject(this, 0, 0, true))) {
m_pRootDict = pMainDict->GetDictFor("Root");
pMainDict->Release();
}
break;
}
}
}