Add fallback fonts in pdfium

core/fpdfapi/fpdf_font/include/cpdf_font.h

 // 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_FPDFAPI_FPDF_FONT_INCLUDE_CPDF_FONT_H_
 #define CORE_FPDFAPI_FPDF_FONT_INCLUDE_CPDF_FONT_H_
 
 #include <memory>
@@ skipping 53 matching lines @@
   virtual uint32_t GetNextChar(const FX_CHAR* pString,
                                int nStrLen,
                                int& offset) const;
   virtual int CountChar(const FX_CHAR* pString, int size) const;
   virtual int AppendChar(FX_CHAR* buf, uint32_t charcode) const;
   virtual int GetCharSize(uint32_t charcode) const;
   virtual int GlyphFromCharCode(uint32_t charcode, bool* pVertGlyph) = 0;
   virtual int GlyphFromCharCodeExt(uint32_t charcode);
   virtual CFX_WideString UnicodeFromCharCode(uint32_t charcode) const;
   virtual uint32_t CharCodeFromUnicode(FX_WCHAR Unicode) const;
+  virtual uint32_t FallbackFontFromCharcode(uint32_t charcode,

[dsinclair, 2016/08/23 19:41:18]

Are either of these overridden by subclasses? If not, lets remove the virtual
for now.

[npm, 2016/08/23 20:36:57]

Done.

+                                            bool* pVertGlyph);
+  virtual int FallbackGlyphFromCharcode(int fallbackFont,
+                                        uint32_t charcode,
+                                        bool* pVertGlyph);
 
   const CFX_ByteString& GetBaseFont() const { return m_BaseFont; }
   CFX_SubstFont* GetSubstFont() const { return m_Font.GetSubstFont(); }
   uint32_t GetFlags() const { return m_Flags; }
   FX_BOOL IsEmbedded() const { return IsType3Font() || m_pFontFile != nullptr; }
   CPDF_StreamAcc* GetFontFile() const { return m_pFontFile; }
   CPDF_Dictionary* GetFontDict() const { return m_pFontDict; }
   FX_BOOL IsStandardFont() const;
   FXFT_Face GetFace() const { return m_Font.GetFace(); }
   void AppendChar(CFX_ByteString& str, uint32_t charcode) const;
 
   void GetFontBBox(FX_RECT& rect) const { rect = m_FontBBox; }
   int GetTypeAscent() const { return m_Ascent; }
   int GetTypeDescent() const { return m_Descent; }
   int GetItalicAngle() const { return m_ItalicAngle; }
   int GetStemV() const { return m_StemV; }
   int GetStringWidth(const FX_CHAR* pString, int size);
 
   virtual int GetCharWidthF(uint32_t charcode, int level = 0) = 0;
   virtual FX_RECT GetCharBBox(uint32_t charcode, int level = 0) = 0;
 
   CPDF_Document* m_pDocument;
   CFX_Font m_Font;
+  std::vector<CFX_Font*> m_FontPlusFallbacks;
 
  protected:
   CPDF_Font();
 
   virtual FX_BOOL Load() = 0;
 
   FX_BOOL Initialize();
   void LoadUnicodeMap() const;  // logically const only.
   void LoadPDFEncoding(CPDF_Object* pEncoding,
                        int& iBaseEncoding,
@@ skipping 14 matching lines @@
   mutable FX_BOOL m_bToUnicodeLoaded;
   int m_Flags;
   FX_RECT m_FontBBox;
   int m_StemV;
   int m_Ascent;
   int m_Descent;
   int m_ItalicAngle;
 };
 
 #endif  // CORE_FPDFAPI_FPDF_FONT_INCLUDE_CPDF_FONT_H_