ui/gfx/font_fallback_win.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_GFX_FONT_FALLBACK_WIN_H_
   6 #define UI_GFX_FONT_FALLBACK_WIN_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "ui/gfx/font.h"
  12
  13 namespace gfx {
  14
  15 // Internals of font_fallback_win.cc exposed for testing.
  16 namespace internal {
  17
  18 // Parses comma separated SystemLink |entry|, per the format described here:
  19 // http://msdn.microsoft.com/en-us/goglobal/bb688134.aspx
  20 //
  21 // Sets |filename| and |font_name| respectively. If a field is not present
  22 // or could not be parsed, the corresponding parameter will be cleared.
  23 void GFX_EXPORT ParseFontLinkEntry(const std::string& entry,
  24                                   std::string* filename,
  25                                   std::string* font_name);
  26
  27 // Parses a font |family| in the format "FamilyFoo & FamilyBar (TrueType)".
  28 // Splits by '&' and strips off the trailing parenthesized expression.
  29 void GFX_EXPORT ParseFontFamilyString(const std::string& family,
  30                                      std::vector<std::string>* font_names);
  31
  32 }  // namespace internal
  33
  34 // Iterator over linked fallback fonts for a given font. The linked font chain
  35 // comes from the Windows registry, but gets cached between uses.
  36 class GFX_EXPORT LinkedFontsIterator {
  37  public:
  38   // Instantiates the iterator over the linked font chain for |font|. The first
  39   // item will be |font| itself.
  40   explicit LinkedFontsIterator(Font font);
  41   virtual ~LinkedFontsIterator();
  42
  43   // Sets the font that would be returned by the next call to |NextFont()|,
  44   // useful for inserting one-time entries into the iterator chain.
  45   void SetNextFont(Font font);
  46
  47   // Gets the next font in the link chain, if available, and increments the
  48   // iterator. Returns |true| on success or |false| if the iterator is past
  49   // last item (in that case, the value of |font| should not be used). If
  50   // |SetNextFont()| was called, returns the font set that way and clears it.
  51   bool NextFont(Font* font);
  52
  53  protected:
  54   // Retrieves the list of linked fonts. Protected and virtual so that it may
  55   // be overridden by tests.
  56   virtual const std::vector<Font>* GetLinkedFonts() const;
  57
  58  private:
  59   // Original font whose linked fonts are being iterated over.
  60   Font original_font_;
  61
  62   // Font that was set via |SetNextFont()|.
  63   Font next_font_;
  64
  65   // Indicates whether |SetNextFont()| was called.
  66   bool next_font_set_;
  67
  68   // The font most recently returned by |NextFont()|.
  69   Font current_font_;
  70
  71   // List of linked fonts; weak pointer.
  72   const std::vector<Font>* linked_fonts_;
  73
  74   // Index of the current entry in the |linked_fonts_| list.
  75   size_t linked_font_index_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(LinkedFontsIterator);
  78 };
  79
  80 }  // namespace gfx
  81
  82 #endif  // UI_GFX_FONT_FALLBACK_WIN_H_