Modify content::GetFontTable so clients can control what is read.

chrome/renderer/pepper/ppb_pdf_impl.cc

 // Copyright (c) 2012 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 "chrome/renderer/pepper/ppb_pdf_impl.h"
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
+#include "base/safe_numerics.h"
 #include "base/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/renderer/printing/print_web_view_helper.h"
 #include "content/public/common/child_process_sandbox_support_linux.h"
 #include "content/public/common/content_client.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/public/renderer/render_view.h"
 #include "grit/webkit_resources.h"
@@ skipping 35 matching lines @@
   PrivateFontFile(PP_Instance instance, int fd)
       : Resource(ppapi::OBJECT_IS_IMPL, instance),
         fd_(fd) {
   }
 
   bool GetFontTable(uint32_t table,
                     void* output,
                     uint32_t* output_length) {
     size_t temp_size = static_cast<size_t>(*output_length);
     bool rv = content::GetFontTable(
-        fd_, table, static_cast<uint8_t*>(output), &temp_size);
-    *output_length = static_cast<uint32_t>(temp_size);
+        fd_, table, 0 /* offset */, static_cast<uint8_t*>(output), &temp_size);
+    *output_length = base::checked_numeric_cast<uint32_t>(temp_size);
     return rv;
   }
 
  protected:
   virtual ~PrivateFontFile() {}
 
  private:
   int fd_;
 };
 #endif
@@ skipping 343 matching lines @@
   WebKit::WebElement element = instance->container()->element();
   WebKit::WebView* view = element.document().frame()->view();
   content::RenderView* render_view = content::RenderView::FromWebView(view);
 
   using printing::PrintWebViewHelper;
   PrintWebViewHelper* print_view_helper = PrintWebViewHelper::Get(render_view);
   if (print_view_helper)
     print_view_helper->PrintNode(element);
 #endif
 }