Implement SharedMemory::NewAnonymousReadOnly(contents).

chrome/browser/extensions/user_script_master.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/browser/extensions/user_script_master.h"
 
 #include <map>
 #include <string>
 #include <vector>
 
@@ skipping 267 matching lines @@
       base::StringPiece contents = script.js_scripts()[j].GetContent();
       pickle.WriteData(contents.data(), contents.length());
     }
     for (size_t j = 0; j < script.css_scripts().size(); j++) {
       base::StringPiece contents = script.css_scripts()[j].GetContent();
       pickle.WriteData(contents.data(), contents.length());
     }
   }
 
   // Create the shared memory object.
-  scoped_ptr<base::SharedMemory> shared_memory(new base::SharedMemory());
+  base::SharedMemory shared_memory;
 
-  if (!shared_memory->CreateAndMapAnonymous(pickle.size()))
+  if (!shared_memory.CreateAndMapAnonymous(pickle.size()))
     return NULL;
 
   // Copy the pickle to shared memory.
-  memcpy(shared_memory->memory(), pickle.data(), pickle.size());
+  memcpy(shared_memory.memory(), pickle.data(), pickle.size());
 
-  return shared_memory.release();
+  base::SharedMemoryHandle readonly_handle;
+  if (!shared_memory.ShareReadOnlyToProcess(base::GetCurrentProcessHandle(),
+                                            &readonly_handle))
+    return NULL;
+
+  return new base::SharedMemory(readonly_handle, /*read_only=*/true);
 }
 
 // This method will be called on the file thread.
 void UserScriptMaster::ScriptReloader::RunLoad(
     const UserScriptList& user_scripts) {
   LoadUserScripts(const_cast<UserScriptList*>(&user_scripts));
 
   // Scripts now contains list of up-to-date scripts. Load the content in the
   // shared memory and let the master know it's ready. We need to post the task
   // back even if no scripts ware found to balance the AddRef/Release calls.
@@ skipping 146 matching lines @@
 
   base::SharedMemoryHandle handle_for_process;
   if (!shared_memory->ShareToProcess(handle, &handle_for_process))
     return;  // This can legitimately fail if the renderer asserts at startup.
 
   if (base::SharedMemory::IsHandleValid(handle_for_process))
     process->Send(new ExtensionMsg_UpdateUserScripts(handle_for_process));
 }
 
 }  // namespace extensions