Make SharedMemoryHandle a class on windows.

content/common/dwrite_font_platform_win.cc

 // Copyright 2014 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/public/common/dwrite_font_platform_win.h"
 
 #include <windows.h>
 
 #include <dwrite.h>
+#include <limits>
 #include <map>
 #include <string>
 #include <utility>
 #include <vector>
 #include <wrl/implements.h>
 #include <wrl/wrappers/corewrappers.h>
 
 #include "base/command_line.h"
 #include "base/debug/alias.h"
 #include "base/debug/crash_logging.h"
@@ skipping 910 matching lines @@
   return iter != cache_map_.end();;
 }
 
 bool FontCollectionLoader::LoadCacheFile() {
   std::string font_cache_handle_string =
       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
           switches::kFontCacheSharedHandle);
   if (font_cache_handle_string.empty())
     return false;
 
-  base::SharedMemoryHandle font_cache_handle = NULL;
-  base::StringToUint(font_cache_handle_string,
-                     reinterpret_cast<unsigned int*>(&font_cache_handle));
-  DCHECK(font_cache_handle);
+  unsigned int handle_uint;
+  base::StringToUint(font_cache_handle_string, &handle_uint);
+  DCHECK(handle_uint);
+  if (handle_uint > static_cast<unsigned int>(std::numeric_limits<long>::max()))
+    return false;
+  base::SharedMemoryHandle font_cache_handle(LongToHandle(handle_uint),
+                                             base::GetCurrentProcId());
 
   base::SharedMemory* shared_mem = new base::SharedMemory(
       font_cache_handle, true);
   // Map the cache file into memory.
   shared_mem->Map(0);
 
   cache_.reset(shared_mem);
 
   if (base::StartsWith(base::FieldTrialList::FindFullName("LightSpeed"),
                        "PrefetchDWriteFontCache",
@@ skipping 300 matching lines @@
   g_shared_font_cache.Set(mapping);
 
   return true;
 }
 
 bool BuildFontCache(const base::FilePath& file) {
   return BuildFontCacheInternal(file.value().c_str());
 }
 
 }  // namespace content