Remove write abilities from CFX_SeekableStreamProxy

This CL removes the abliity to write to the seekable stream proxy class.

Change-Id: I0eda2619714df190d326c23dfdcd4527d4312779
Reviewed-on: https://pdfium-review.googlesource.com/30853
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

3 files changed, 5 insertions, 41 deletions

diff --git a/core/fxcrt/cfx_seekablestreamproxy.cpp b/core/fxcrt/cfx_seekablestreamproxy.cpp
index 989c440db1..44a212d867 100644
--- a/core/fxcrt/cfx_seekablestreamproxy.cpp
+++ b/core/fxcrt/cfx_seekablestreamproxy.cpp
@@ -134,20 +134,13 @@ void SwapByteOrder(wchar_t* pStr, size_t iLength) {
 #define BOM_UTF16_LE 0x0000FEFF
 
 CFX_SeekableStreamProxy::CFX_SeekableStreamProxy(
-    const RetainPtr<IFX_SeekableStream>& stream,
-    bool isWriteStream)
-    : m_IsWriteStream(isWriteStream),
-      m_wCodePage(FX_CODEPAGE_DefANSI),
+    const RetainPtr<IFX_SeekableStream>& stream)
+    : m_wCodePage(FX_CODEPAGE_DefANSI),
       m_wBOMLength(0),
       m_iPosition(0),
       m_pStream(stream) {
   ASSERT(m_pStream);
 
-  if (isWriteStream) {
-    m_iPosition = m_pStream->GetSize();
-    return;
-  }
-
   Seek(From::Begin, 0);
 
   uint32_t bom = 0;
@@ -176,8 +169,7 @@ CFX_SeekableStreamProxy::CFX_SeekableStreamProxy(
 
 CFX_SeekableStreamProxy::CFX_SeekableStreamProxy(uint8_t* data, size_t size)
     : CFX_SeekableStreamProxy(
-          pdfium::MakeRetain<CFX_MemoryStream>(data, size, false),
-          false) {}
+          pdfium::MakeRetain<CFX_MemoryStream>(data, size, false)) {}
 
 CFX_SeekableStreamProxy::~CFX_SeekableStreamProxy() {}
 
@@ -206,9 +198,6 @@ void CFX_SeekableStreamProxy::SetCodePage(uint16_t wCodePage) {
 size_t CFX_SeekableStreamProxy::ReadData(uint8_t* pBuffer, size_t iBufferSize) {
   ASSERT(pBuffer && iBufferSize > 0);
 
-  if (m_IsWriteStream)
-    return 0;
-
   iBufferSize =
       std::min(iBufferSize, static_cast<size_t>(GetLength() - m_iPosition));
   if (iBufferSize <= 0)
@@ -229,9 +218,6 @@ size_t CFX_SeekableStreamProxy::ReadString(wchar_t* pStr,
   if (!pStr || iMaxLength == 0)
     return 0;
 
-  if (m_IsWriteStream)
-    return 0;
-
   if (m_wCodePage == FX_CODEPAGE_UTF16LE ||
       m_wCodePage == FX_CODEPAGE_UTF16BE) {
     size_t iBytes = iMaxLength * 2;
@@ -267,20 +253,3 @@ size_t CFX_SeekableStreamProxy::ReadString(wchar_t* pStr,
   *bEOS = IsEOF();
   return iMaxLength;
 }
-
-void CFX_SeekableStreamProxy::WriteString(const WideStringView& str) {
-  if (!m_IsWriteStream || str.GetLength() == 0 ||
-      m_wCodePage != FX_CODEPAGE_UTF8) {
-    return;
-  }
-  if (!m_pStream->WriteBlock(str.unterminated_c_str(), m_iPosition,
-                             str.GetLength() * sizeof(wchar_t))) {
-    return;
-  }
-
-  pdfium::base::CheckedNumeric<FX_FILESIZE> new_pos = m_iPosition;
-  new_pos += str.GetLength() * sizeof(wchar_t);
-  m_iPosition = new_pos.ValueOrDefault(std::numeric_limits<FX_FILESIZE>::max());
-  m_iPosition =
-      pdfium::clamp(m_iPosition, static_cast<FX_FILESIZE>(0), GetLength());
-}
diff --git a/core/fxcrt/cfx_seekablestreamproxy.h b/core/fxcrt/cfx_seekablestreamproxy.h
index c25ab3c9b6..451f7769c2 100644
--- a/core/fxcrt/cfx_seekablestreamproxy.h
+++ b/core/fxcrt/cfx_seekablestreamproxy.h
@@ -31,20 +31,16 @@ class CFX_SeekableStreamProxy : public Retainable {
   void Seek(From eSeek, FX_FILESIZE iOffset);
   size_t ReadString(wchar_t* pStr, size_t iMaxLength, bool* bEOS);
 
-  void WriteString(const WideStringView& str);
-
   uint16_t GetCodePage() const { return m_wCodePage; }
   void SetCodePage(uint16_t wCodePage);
 
  private:
-  CFX_SeekableStreamProxy(const RetainPtr<IFX_SeekableStream>& stream,
-                          bool isWriteSteam);
+  explicit CFX_SeekableStreamProxy(const RetainPtr<IFX_SeekableStream>& stream);
   CFX_SeekableStreamProxy(uint8_t* data, size_t size);
   ~CFX_SeekableStreamProxy() override;
 
   size_t ReadData(uint8_t* pBuffer, size_t iBufferSize);
 
-  bool m_IsWriteStream;
   uint16_t m_wCodePage;
   size_t m_wBOMLength;
   FX_FILESIZE m_iPosition;
diff --git a/xfa/fxfa/parser/cxfa_document_parser.cpp b/xfa/fxfa/parser/cxfa_document_parser.cpp
index 32bcba0609..f52d52ff3c 100644
--- a/xfa/fxfa/parser/cxfa_document_parser.cpp
+++ b/xfa/fxfa/parser/cxfa_document_parser.cpp
@@ -329,8 +329,7 @@ CXFA_DocumentParser::~CXFA_DocumentParser() {}
 
 bool CXFA_DocumentParser::Parse(const RetainPtr<IFX_SeekableStream>& pStream,
                                 XFA_PacketType ePacketID) {
-  auto pStreamProxy =
-      pdfium::MakeRetain<CFX_SeekableStreamProxy>(pStream, false);
+  auto pStreamProxy = pdfium::MakeRetain<CFX_SeekableStreamProxy>(pStream);
   uint16_t wCodePage = pStreamProxy->GetCodePage();
   if (wCodePage != FX_CODEPAGE_UTF16LE && wCodePage != FX_CODEPAGE_UTF16BE &&
       wCodePage != FX_CODEPAGE_UTF8) {