Mac: Part 1 of a fix to get OOP font loading working in the renderer on 10.6.6 .

content/common/font_loader_mac.mm

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/font_loader_mac.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/basictypes.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/mac/mac_util.h"
 #include "base/sys_string_conversions.h"
 
 // static
 bool FontLoader::LoadFontIntoBuffer(NSFont* font_to_encode,
                                     base::SharedMemory* font_data,
-                                    uint32* font_data_size) {
-  CHECK(font_data && font_data_size);
+                                    uint32* font_data_size,
+                                    uint32* font_id) {
+  CHECK(font_data && font_data_size && font_id);

[Nico, 2011/05/30 13:19:37]

I'd make this 3 separate CHECK statements, that gives you more information when
it fails

   *font_data_size = 0;
+  *font_id = 0;
 
   // Used only for logging.
   std::string font_name([[font_to_encode fontName] UTF8String]);
 
   // Load appropriate NSFont.
   if (!font_to_encode) {
     LOG(ERROR) << "Failed to load font " << font_name;
     return false;
   }
 
   // NSFont -> ATSFontRef.
   ATSFontRef ats_font =
       CTFontGetPlatformFont(reinterpret_cast<CTFontRef>(font_to_encode), NULL);
   if (!ats_font) {
     LOG(ERROR) << "Conversion to ATSFontRef failed for " << font_name;
     return false;
   }
 
+  // Retrieve the ATSFontContainerRef corresponding to the font file we want to
+  // load. This is a unique identifier that allows the caller determine if the
+  // font file in question is already loaded.
+  COMPILE_ASSERT(sizeof(ATSFontContainerRef) == sizeof(font_id),
+      uint32_cant_hold_fontcontainer_ref);
+  ATSFontContainerRef fontContainer = kATSFontContainerRefUnspecified;
+  if (ATSFontGetContainer(ats_font, 0, &fontContainer) != noErr) {
+      LOG(ERROR) << "Failed to get font container ref for " << font_name;
+      return false;
+  }
+
   // ATSFontRef -> File path.
   // Warning: Calling this function on a font activated from memory will result
   // in failure with a -50 - paramErr.  This may occur if
   // CreateCGFontFromBuffer() is called in the same process as this function
   // e.g. when writing a unit test that exercises these two functions together.
   // If said unit test were to load a system font and activate it from memory
   // it becomes impossible for the system to the find the original file ref
   // since the font now lives in memory as far as it's concerned.
   FSRef font_fsref;
   if (ATSFontGetFileReference(ats_font, &font_fsref) != noErr) {
@@ skipping 22 matching lines @@
 
   int32 amt_read = file_util::ReadFile(font_path,
                        reinterpret_cast<char*>(font_data->memory()),
                        font_file_size_32);
   if (amt_read != font_file_size_32) {
     LOG(ERROR) << "Failed to read font data for " << font_path.value();
     return false;
   }
 
   *font_data_size = font_file_size_32;
+  *font_id = fontContainer;
   return true;
 }
 
 // static
 bool FontLoader::ATSFontContainerFromBuffer(base::SharedMemoryHandle font_data,
                                             uint32 font_data_size,
                                             ATSFontContainerRef* font_container)
 {
   CHECK(font_container);
 
   using base::SharedMemory;
   DCHECK(SharedMemory::IsHandleValid(font_data));
   DCHECK_GT(font_data_size, 0U);
 
   SharedMemory shm(font_data, true);
   if (!shm.Map(font_data_size))
     return false;
 
   // A value of 3 means the font is private and can't be seen by anyone else.
   // This is the value used by WebKit when activating remote fonts.
   const ATSFontContext kFontContextPrivate = 3;
   OSStatus err = ATSFontActivateFromMemory(shm.memory(), font_data_size,
                     kFontContextPrivate, kATSFontFormatUnspecified, NULL,
                     kATSOptionFlagsDefault, font_container);
   if (err != noErr || !font_container)
     return false;
 
   return true;
 }