Autofill phone number enhancements and integration of Phone Number Util Library: part 1

third_party/libphonenumber/cpp/src/base/at_exit.cc

+// Copyright (c) 2006-2008 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/at_exit.h"
+#include "base/logging.h"
+
+namespace base {
+
+// Keep a stack of registered AtExitManagers.  We always operate on the most
+// recent, and we should never have more than one outside of testing, when we
+// use the shadow version of the constructor.  We don't protect this for
+// thread-safe access, since it will only be modified in testing.
+static AtExitManager* g_top_manager = NULL;
+
+AtExitManager::AtExitManager() : next_manager_(NULL) {
+  DCHECK(!g_top_manager);
+  g_top_manager = this;
+}
+
+AtExitManager::~AtExitManager() {
+  if (!g_top_manager) {
+    NOTREACHED() << "Tried to ~AtExitManager without an AtExitManager";
+    return;
+  }
+  DCHECK(g_top_manager == this);
+
+  ProcessCallbacksNow();
+  g_top_manager = next_manager_;
+}
+
+// static
+void AtExitManager::RegisterCallback(AtExitCallbackType func, void* param) {
+  if (!g_top_manager) {
+    NOTREACHED() << "Tried to RegisterCallback without an AtExitManager";
+    return;
+  }
+
+  DCHECK(func);
+
+  AutoLock lock(g_top_manager->lock_);
+  g_top_manager->stack_.push(CallbackAndParam(func, param));
+}
+
+// static
+void AtExitManager::ProcessCallbacksNow() {
+  if (!g_top_manager) {
+    NOTREACHED() << "Tried to ProcessCallbacksNow without an AtExitManager";
+    return;
+  }
+
+  AutoLock lock(g_top_manager->lock_);
+
+  while (!g_top_manager->stack_.empty()) {
+    CallbackAndParam callback_and_param = g_top_manager->stack_.top();
+    g_top_manager->stack_.pop();
+
+    callback_and_param.func_(callback_and_param.param_);
+  }
+}
+
+AtExitManager::AtExitManager(bool shadow) : next_manager_(g_top_manager) {
+  DCHECK(shadow || !g_top_manager);
+  g_top_manager = this;
+}
+
+}  // namespace base