diff -r 000000000000 -r 6474c204b198 security/sandbox/chromium/base/threading/thread_id_name_manager.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/security/sandbox/chromium/base/threading/thread_id_name_manager.cc	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,113 @@
+// 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 "base/threading/thread_id_name_manager.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "base/logging.h"
+#include "base/memory/singleton.h"
+#include "base/strings/string_util.h"
+
+namespace base {
+namespace {
+
+static const char kDefaultName[] = "";
+static std::string* g_default_name;
+
+}
+
+ThreadIdNameManager::ThreadIdNameManager()
+    : main_process_name_(NULL),
+      main_process_id_(kInvalidThreadId) {
+  g_default_name = new std::string(kDefaultName);
+
+  AutoLock locked(lock_);
+  name_to_interned_name_[kDefaultName] = g_default_name;
+}
+
+ThreadIdNameManager::~ThreadIdNameManager() {
+}
+
+ThreadIdNameManager* ThreadIdNameManager::GetInstance() {
+  return Singleton<ThreadIdNameManager,
+      LeakySingletonTraits<ThreadIdNameManager> >::get();
+}
+
+const char* ThreadIdNameManager::GetDefaultInternedString() {
+  return g_default_name->c_str();
+}
+
+void ThreadIdNameManager::RegisterThread(PlatformThreadHandle::Handle handle,
+                                         PlatformThreadId id) {
+  AutoLock locked(lock_);
+  thread_id_to_handle_[id] = handle;
+  thread_handle_to_interned_name_[handle] =
+      name_to_interned_name_[kDefaultName];
+}
+
+void ThreadIdNameManager::SetName(PlatformThreadId id, const char* name) {
+  std::string str_name(name);
+
+  AutoLock locked(lock_);
+  NameToInternedNameMap::iterator iter = name_to_interned_name_.find(str_name);
+  std::string* leaked_str = NULL;
+  if (iter != name_to_interned_name_.end()) {
+    leaked_str = iter->second;
+  } else {
+    leaked_str = new std::string(str_name);
+    name_to_interned_name_[str_name] = leaked_str;
+  }
+
+  ThreadIdToHandleMap::iterator id_to_handle_iter =
+      thread_id_to_handle_.find(id);
+
+  // The main thread of a process will not be created as a Thread object which
+  // means there is no PlatformThreadHandler registered.
+  if (id_to_handle_iter == thread_id_to_handle_.end()) {
+    main_process_name_ = leaked_str;
+    main_process_id_ = id;
+    return;
+  }
+  thread_handle_to_interned_name_[id_to_handle_iter->second] = leaked_str;
+}
+
+const char* ThreadIdNameManager::GetName(PlatformThreadId id) {
+  AutoLock locked(lock_);
+
+  if (id == main_process_id_)
+    return main_process_name_->c_str();
+
+  ThreadIdToHandleMap::iterator id_to_handle_iter =
+      thread_id_to_handle_.find(id);
+  if (id_to_handle_iter == thread_id_to_handle_.end())
+    return name_to_interned_name_[kDefaultName]->c_str();
+
+  ThreadHandleToInternedNameMap::iterator handle_to_name_iter =
+      thread_handle_to_interned_name_.find(id_to_handle_iter->second);
+  return handle_to_name_iter->second->c_str();
+}
+
+void ThreadIdNameManager::RemoveName(PlatformThreadHandle::Handle handle,
+                                     PlatformThreadId id) {
+  AutoLock locked(lock_);
+  ThreadHandleToInternedNameMap::iterator handle_to_name_iter =
+      thread_handle_to_interned_name_.find(handle);
+
+  DCHECK(handle_to_name_iter != thread_handle_to_interned_name_.end());
+  thread_handle_to_interned_name_.erase(handle_to_name_iter);
+
+  ThreadIdToHandleMap::iterator id_to_handle_iter =
+      thread_id_to_handle_.find(id);
+  DCHECK((id_to_handle_iter!= thread_id_to_handle_.end()));
+  // The given |id| may have been re-used by the system. Make sure the
+  // mapping points to the provided |handle| before removal.
+  if (id_to_handle_iter->second != handle)
+    return;
+
+  thread_id_to_handle_.erase(id_to_handle_iter);
+}
+
+}  // namespace base