content/common/mac/font_loader.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 CONTENT_COMMON_MAC_FONT_LOADER_H_
   6 #define CONTENT_COMMON_MAC_FONT_LOADER_H_
   7
   8 #include <ApplicationServices/ApplicationServices.h>
   9
  10 #include "base/memory/shared_memory.h"
  11 #include "content/common/content_export.h"
  12
  13 #ifdef __OBJC__
  14 @class NSFont;
  15 #else
  16 class NSFont;
  17 #endif
  18
  19 struct FontDescriptor;
  20
  21 // Provides functionality to transmit fonts over IPC.
  22 //
  23 // Note about font formats: .dfont (datafork suitcase) fonts are currently not
  24 // supported by this code since CGFontCreateWithDataProvider() can't handle them
  25 // directly.
  26
  27 class FontLoader {
  28  public:
  29   // This structure holds the result of LoadFont(). This structure is passed to
  30   // LoadFont(), which should run on the file thread, then it is passed to a
  31   // task which sends the result to the originating renderer.
  32   struct Result {
  33     uint32 font_data_size;
  34     base::SharedMemory font_data;
  35     uint32 font_id;
  36   };
  37   // Load a font specified by |font| into a shared memory buffer suitable for
  38   // sending over IPC.
  39   //
  40   // On return:
  41   //  |result->font_data| - shared memory buffer containing the raw data for
  42   // the font file. The buffer is only valid when both |result->font_data_size|
  43   // and |result->font_id| are not zero.
  44   //  |result->font_data_size| - size of data contained in |result->font_data|.
  45   // This value is zero on failure.
  46   //  |result->font_id| - unique identifier for the on-disk file we load for
  47   // the font. This value is zero on failure.
  48   CONTENT_EXPORT
  49   static void LoadFont(const FontDescriptor& font, FontLoader::Result* result);
  50
  51   // Given a shared memory buffer containing the raw data for a font file, load
  52   // the font and return a CGFontRef.
  53   //
  54   // |data| - A shared memory handle pointing to the raw data from a font file.
  55   // |data_size| - Size of |data|.
  56   //
  57   // On return:
  58   //  returns true on success, false on failure.
  59   //  |out| - A CGFontRef corresponding to the designated font.
  60   //  The caller is responsible for releasing this value via CGFontRelease()
  61   //  when done.
  62   CONTENT_EXPORT
  63   static bool CGFontRefFromBuffer(base::SharedMemoryHandle font_data,
  64                                   uint32 font_data_size,
  65                                   CGFontRef* out);
  66 };
  67
  68 #endif  // CONTENT_COMMON_MAC_FONT_LOADER_H_