// 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. | |
#ifndef BASE_AT_EXIT_H_ | |
#define BASE_AT_EXIT_H_ | |
#include <stack> | |
#include "base/basictypes.h" | |
#include "base/lock.h" | |
namespace base { | |
// This class provides a facility similar to the CRT atexit(), except that | |
// we control when the callbacks are executed. Under Windows for a DLL they | |
// happen at a really bad time and under the loader lock. This facility is | |
// mostly used by base::Singleton. | |
// | |
// The usage is simple. Early in the main() or WinMain() scope create an | |
// AtExitManager object on the stack: | |
// int main(...) { | |
// base::AtExitManager exit_manager; | |
// | |
// } | |
// When the exit_manager object goes out of scope, all the registered | |
// callbacks and singleton destructors will be called. | |
class AtExitManager { | |
protected: | |
// This constructor will allow this instance of AtExitManager to be created | |
// even if one already exists. This should only be used for testing! | |
// AtExitManagers are kept on a global stack, and it will be removed during | |
// destruction. This allows you to shadow another AtExitManager. | |
AtExitManager(bool shadow); | |
public: | |
typedef void (*AtExitCallbackType)(); | |
AtExitManager(); | |
// The dtor calls all the registered callbacks. Do not try to register more | |
// callbacks after this point. | |
~AtExitManager(); | |
// Registers the specified function to be called at exit. The prototype of | |
// the callback function is void func(). | |
static void RegisterCallback(AtExitCallbackType func); | |
// Calls the functions registered with RegisterCallback in LIFO order. It | |
// is possible to register new callbacks after calling this function. | |
static void ProcessCallbacksNow(); | |
private: | |
Lock lock_; | |
std::stack<AtExitCallbackType> stack_; | |
AtExitManager* next_manager_; // Stack of managers to allow shadowing. | |
DISALLOW_COPY_AND_ASSIGN(AtExitManager); | |
}; | |
} // namespace base | |
#endif // BASE_AT_EXIT_H_ | |